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Sample records for phosphate transport system

  1. Modeling transport kinetics in clinoptilolite-phosphate rock systems

    NASA Technical Reports Server (NTRS)

    Allen, E. R.; Ming, D. W.; Hossner, L. R.; Henninger, D. L.

    1995-01-01

    Nutrient release in clinoptilolite-phosphate rock (Cp-PR) systems occurs through dissolution and cation-exchange reactions. Investigating the kinetics of these reactions expands our understanding of nutrient release processes. Research was conducted to model transport kinetics of nutrient release in Cp-PR systems. The objectives were to identify empirical models that best describe NH4, K, and P release and define diffusion-controlling processes. Materials included a Texas clinoptilolite (Cp) and North Carolina phosphate rock (PR). A continuous-flow thin-disk technique was used. Models evaluated included zero order, first order, second order, parabolic diffusion, simplified Elovich, Elovich, and power function. The power-function, Elovich, and parabolic-diffusion models adequately described NH4, K, and P release. The power-function model was preferred because of its simplicity. Models indicated nutrient release was diffusion controlled. Primary transport processes controlling nutrient release for the time span observed were probably the result of a combination of several interacting transport mechanisms.

  2. Kinetics of exogenous induction of the hexose-6-phosphate transport system of Escherichia coli.

    PubMed

    Winkler, H H

    1971-07-01

    The kinetics of the exogenous induction of the hexose-phosphate transport system by glucose-6-phosphate (G6P) was investigated. The induction of this system by extracellular but not intracellular G6P was confirmed. The differential rate of synthesis was linear, a function of the extracellular concentration of G6P and independent of the previous induction history of the culture. Neither maintenance nor autocatalysis, phenomena described in the induction of the lac operon, were observed in the exogenous induction of hexose-phosphate transport. Fructose-6-phosphate, a potent competitive inhibitor of G6P influx, had no effect on the induction of the system by G6P, indicating that the transport of inducer was not involved in the induction process. PMID:4935331

  3. Characterization of two genetically separable inorganic phosphate transport systems in Escherichia coli.

    PubMed Central

    Willsky, G R; Malamy, M H

    1980-01-01

    Inorganic phosphate (Pi) transport by wild-type cells of Escherichia coli grown in excess phosphate-containing media involves two genetically separable transport systems. Cells dependent upon the high affinity-low velocity Pst (phosphate specific transport) system have a Km of 0.43 +/- 0.2 microM Pi and a Vmax of 15.9 +/- 0.3 nmol of Pi (mg [dry weight]-1min-1) and will grow in the presence of arsenate in the medium. However, cells dependent upon the low affinity-high velocity Pit (Pi transport) system have a Km of 38.2 +/- 0.4 microM and a Vmax of 55 +/- 1.9 nmol of Pi (mg [dry weight]-1min-1), and these cells cannot grow in the presence of an arsenate-to-Pi ratio of 10 in the medium. Pi transport by both systems was sensitive to the energy uncoupler 2,4-dinitrophenol and the sulfhydryl reagent N-ethylmaleimide, whereas only the Pst system was very sensitive to sodium cyanide. Evidence is presented that Pi is transported as Pi or a very labile intermediate and that accumulated Pi does not exit through the Pst or Pit systems from glucose-grown cells. Kinetic analysis of Pi transport in the wild-type strain containing both the Pst and Pit transport systems revealed that each system was not operating at full capacity. In addition, Pi transport in the wild-type strain was completely sensitive to sodium cyanide (a characteristic of the Pst system). PMID:6998957

  4. A phosphate transport system is required for symbiotic nitrogen fixation by Rhizobium meliloti.

    PubMed Central

    Bardin, S; Dan, S; Osteras, M; Finan, T M

    1996-01-01

    The bacterium Rhizobium meliloti forms N2-fixing root nodules on alfalfa plants. The ndvF locus, located on the 1,700-kb pEXO megaplasmid of R. meliloti, is required for nodule invasion and N2 fixation. Here we report that ndvF contains four genes, phoCDET, which encode an ABC-type transport system for the uptake of Pi into the bacteria. The PhoC and PhoD proteins are homologous to the Escherichia coli phosphonate transport proteins PhnC and PhnD. The PhoT and PhoE proteins are homologous to each other and to the E. coli phosphonate transport protein PhnE. We show that the R. meliloti phoD and phoE genes are induced in response to phosphate starvation and that the phoC promoter contains two elements which are similar in sequence to the PHO boxes present in E. coli phosphate-regulated promoters. The R. meliloti ndvF mutants grow poorly at a phosphate concentration of 2 mM, and we hypothesize that their symbiotic phenotype results from their failure to grow during the nodule infection process. Presumably, the PhoCDET transport system is employed by the bacteria in the soil environment, where the concentration of available phosphate is normally 0.1 to 1 microM. PMID:8755882

  5. Phosphate transport and arsenate resistance in the cyanobacterium Anabaena variabilis

    SciTech Connect

    Thiel, T.

    1988-03-01

    Cells of the cyanobacterium Anabaena variabilis starved for phosphate for 3 days took up phosphate at about 100 times the rate of unstarved cells.Kinetic data suggested that a new transport system had been induced by starvation for phosphate. The inducible phosphate transport system was quickly repressed by addition of P/sub i/. Phosphate-starved cells were more sensitive to the toxic effects of arsenate than were unstarved cells, but phosphate could alleviate some of the toxicity. Arsenate was a noncompetitive inhibitor of phosphate transport; however, the apparent K/sub i/ values were high, particularly for phosphate-replete cells. Preincubation of phosphate-starved cells with arsenate caused subsequent inhibition of phosphate transport, suggesting that intracellular arsenate inhibited phosphate transport. This effect was not seen in phosphate-replete cells.

  6. Lack of Control in Inorganic Phosphate Uptake by Catharanthus roseus (L.) G. Don Cells (Cytoplasmic Inorganic Phosphate Homeostasis Depends on the Tonoplast Inorganic Phosphate Transport System?).

    PubMed Central

    Sakano, K.; Yazaki, Y.; Okihara, K.; Mimura, T.; Kiyota, S.

    1995-01-01

    Inorganic phosphate (Pi) uptake by Catharanthus roseus (L.) G. Don cells was studied in relation to its apparent uncontrolled uptake using 31P-nuclear magnetic resonance spectroscopy. Kinetics of Pi uptake by the cells indicated that apparent Km and Vm were about 7 [mu]M and 20 [mu]mol g-1 fresh weight h-1, respectively. Pi uptake in Murashige-Skoog medium under different Pi concentrations and different initial cell densities followed basically the same kinetics. When supplied with abundant Pi, cells absorbed Pi at a constant rate (Vm) for the first hours and accumulated it in the vacuole. As the endogenous pool expanded, the rate of Pi uptake gradually decreased to nil. Maximum Pi accumulation was 100 to 120 [mu]mol g-1 fresh weight if cell swelling during Pi uptake (about 2-fold in cell volume) was not considered. Results indicated that (a) the rate of Pi uptake by Catharanthus cells was independent of initial cell density and was constant over a wide range of Pi concentrations (2 mM to about 10 [mu]M) unless the cells were preloaded with excess Pi, and (b) there was no apparent feedback control over the Pi uptake process in the plasma membrane to avoid Pi toxicity. The importance of the tonoplast Pi transport system in cytoplasmic Pi homeostasis is discussed. PMID:12228474

  7. Genetic analysis of mutants affected in the Pst inorganic phosphate transport system.

    PubMed Central

    Cox, G B; Rosenberg, H; Downie, J A; Silver, S

    1981-01-01

    A number of mutant alleles affecting the Pst phosphate transport system have been divided into three complementation groups on the basis of constitutive alkaline phosphatase activity in appropriate partial diploid strains. The three complementation groups were represented by the alleles pstA2 and phoT32 and the newly described allele pstB401. The two alleles phoS28 and phoS21 appeared to be polar. The phoS28 allele affected both the phoT and pstB genes but not the pstA gene, whereas the phoS21 allele appeared to be a mutation in the pstA gene exerting polar effects on both the pstB and phoT genes. It was concluded that the three genes pstA, pstB, and phoT were part of an operon and that the phosphate-binding protein was not coded for by any of these genes. The phoS gene, defined as the structural gene for the phosphate-binding protein, is also part of the operon, but the phoS28 and phoS21 alleles are not mutations in the phoS gene and were reclassified as pho-28 and pho-21 alleles. The gene order was concluded to be pstA-(pstB-phoT)-phoS, with the pstA gene promotor proximal and the direction of transcription opposite to that of the nearby unc operon. Images PMID:7026529

  8. Role of uhp genes in expression of the Escherichia coli sugar-phosphate transport system.

    PubMed Central

    Weston, L A; Kadner, R J

    1988-01-01

    The uhpABCT locus of Escherichia coli is responsible for expression of the sugar-phosphate transport system and its induction by external glucose 6-phosphate. Expression of uhpT-lacZ fusions depended on the function of uhpA, uhpB, and uhpC but not of uhpT. A plasmid carrying only uhpT conferred transport activity in a host strain deleted for the uhp region. Thus, uhpT encodes the polypeptide required for transport function, and the other three uhp genes regulate uhpT transcription. The presence of uhpA at elevated copy number resulted in a substantial increase in uhpT expression. This elevated expression was only about 50% of the level seen in induced haploid cells, and no further increase occurred after addition of inducer. Activation by multicopy uhpA was not affected by the status of uhpC but was decreased in the absence of uhpB, suggesting a role for UhpB in directly activating UhpA. Transcription of uhpA, monitored by expression of a uhpA-lacZ fusion, was not affected by either inducer or the presence of the wild-type uhpA allele. The presence of multiple copies of the uhpT promoter region reduced uhpT expression in strains with uhpA in single copy number but not in those with multiple copies, consistent with competition for the activator. Amino acid sequence comparisons showed that UhpA was homologous to a family of bacterial regulatory proteins, some of which act as transcriptional activators (OmpR, PhoB, NtrC, and DctD). The C-terminal portion of UhpB displayed matches to the corresponding portions of another family of proteins (EnvZ, PhoMR, NtrB, and DctB) that participate in regulation of gene expression in response to environmental factors. PMID:3042748

  9. The Role of Sphingosine-1-phosphate Transporter Spns2 in Immune System Function

    PubMed Central

    Nijnik, Anastasia; Clare, Simon; Hale, Christine; Chen, Jing; Raisen, Claire; Mottram, Lynda; Lucas, Mark; Estabel, Jeanne; Ryder, Edward; Adissu, Hibret; Adams, Niels C.; Ramirez-Solis, Ramiro; White, Jacqueline K.; Steel, Karen P.; Dougan, Gordon; Hancock, Robert E.W.

    2012-01-01

    Sphingosine-1-phosphate (S1P) is lipid messenger involved in the regulation of embryonic development, immune system functions, and many other physiological processes. However the mechanisms of S1P transport across cellular membranes remain poorly understood with several ATP-binding cassette family members and the spinster 2 (Spns2) member of the major facilitator superfamily known to mediate S1P transport in cell culture. Spns2 was also shown to control S1P activities in zebrafish in vivo and to play a critical role in zebrafish cardiovascular development. However the in vivo roles of Spns2 in mammals and its involvement in the different S1P-dependent physiological processes have not been investigated. Here we characterized Spns2-null mouse line carrying the Spns2tm1a(KOMP)Wtsi allele (Spns2tm1a). The Spns2tm1a/tm1a animals were viable, indicating a divergence in Spns2 function from its zebrafish orthologue. However the immunological phenotype of the Spns2tm1a/tm1a mice closely mimicked the phenotypes of partial S1P deficiency and impaired S1P-dependent lymphocyte trafficking, with a depletion of lymphocytes in circulation, an increase in mature single-positive T cells in the thymus, and a selective reduction in mature B cells in the spleen and bone marrow. Spns2 activity in the non-hematopoietic cells was critical for normal lymphocyte development and localization. Overall Spns2tm1a/tm1a resulted in impaired humoral immune responses to immunization. This work thus demonstrated a physiological role for Spns2 in mammalian immune system functions but not in cardiovascular development. Other components of the S1P signaling network are investigated as drug targets for immunosuppressive therapy, but the selective action of Spns2 may present an advantage in this regard. PMID:22664872

  10. Long-Sought Vacuolar Phosphate Transporters Identified.

    PubMed

    Bucher, Marcel; Fabiańska, Izabela

    2016-06-01

    The vacuole is an important subcellular compartment that serves as main phosphate storage in plants among other functions. Three recent studies shed light on the underlying molecular mechanisms for vacuolar phosphate transport that had long remained unknown. PMID:27160805

  11. Reducing the genetic redundancy of Arabidopsis PHOSPHATE TRANSPORTER1 transporters to study phosphate uptake and signaling.

    PubMed

    Ayadi, Amal; David, Pascale; Arrighi, Jean-François; Chiarenza, Serge; Thibaud, Marie-Christine; Nussaume, Laurent; Marin, Elena

    2015-04-01

    Arabidopsis (Arabidopsis thaliana) absorbs inorganic phosphate (Pi) from the soil through an active transport process mediated by the nine members of the PHOSPHATE TRANSPORTER1 (PHT1) family. These proteins share a high level of similarity (greater than 61%), with overlapping expression patterns. The resulting genetic and functional redundancy prevents the analysis of their specific roles. To overcome this difficulty, our approach combined several mutations with gene silencing to inactivate multiple members of the PHT1 family, including a cluster of genes localized on chromosome 5 (PHT1;1, PHT1;2, and PHT1;3). Physiological analyses of these lines established that these three genes, along with PHT1;4, are the main contributors to Pi uptake. Furthermore, PHT1;1 plays an important role in translocation from roots to leaves in high phosphate conditions. These genetic tools also revealed that some PHT1 transporters likely exhibit a dual affinity for phosphate, suggesting that their activity is posttranslationally controlled. These lines display significant phosphate deficiency-related phenotypes (e.g. biomass and yield) due to a massive (80%-96%) reduction in phosphate uptake activities. These defects limited the amount of internal Pi pool, inducing compensatory mechanisms triggered by the systemic Pi starvation response. Such reactions have been uncoupled from PHT1 activity, suggesting that systemic Pi sensing is most probably acting downstream of PHT1. PMID:25670816

  12. Phosphate transporters and their function.

    PubMed

    Biber, Jürg; Hernando, Nati; Forster, Ian

    2013-01-01

    Plasma phosphate concentration is maintained within a relatively narrow range by control of renal reabsorption of filtered inorganic phosphate (P(i)). P(i) reabsorption is a transcellular process that occurs along the proximal tubule. P(i) flux at the apical (luminal) brush border membrane represents the rate-limiting step and is mediated by three Na(+)-dependent P(i) cotransporters (members of the SLC34 and SLC20 families). The putative proteins responsible for basolateral P(i) flux have not been identified. The transport mechanism of the two kidney-specific SLC34 proteins (NaPi-IIa and NaPi-IIc) and of the ubiquitously expressed SLC20 protein (PiT-2) has been studied by heterologous expression to reveal important differences in kinetics, stoichiometry, and substrate specificity. Studies on the regulation of the abundance of the respective proteins highlight significant differences in the temporal responses to various hormonal and nonhormonal factors that can influence P(i) homeostasis. The phenotypes of mice deficient in NaPi-IIa and NaPi-IIc indicate that NaPi-IIa is responsible for most P(i) renal reabsorption. In contrast, in the human kidney, NaPi-IIc appears to have a relatively greater role. The physiological relevance of PiT-2 to P(i) reabsorption remains to be elucidated. PMID:23398154

  13. Physiological Roles of the Dual Phosphate Transporter Systems in Low and High Phosphate Conditions and in Capsule Maintenance of Streptococcus pneumoniae D39

    PubMed Central

    Zheng, Jiaqi J.; Sinha, Dhriti; Wayne, Kyle J.; Winkler, Malcolm E.

    2016-01-01

    Unlike most bacteria, Streptococcus pneumoniae (pneumococcus) has two evolutionarily distinct ABC transporters (Pst1 and Pst2) for inorganic phosphate (Pi) uptake. The genes encoding a two-component regulator (PnpRS) are located immediately upstream of the pst1 operon. Both the pst1 and pst2 operons encode putative PhoU-family regulators (PhoU1 and PhoU2) at their ends. This study addresses why S. pneumoniae contains dual Pi uptake systems and the regulation and contribution of the Pst1 and Pst2 systems in conditions of high (mM) Pi amount and low (μM) Pi amount. We show that in unencapsulated mutants, both pst1 and pst2 can be deleted, and Pi is taken up by a third Na+/Pi co-transporter, designated as NptA. In contrast, either pst1 or pst2 is unexpectedly required for the growth of capsule producing strains. We used a combination of mutational analysis, transcript level determinations by qRT-PCR and RNA-Seq, assays for cellular PnpR~P amounts by SDS-PAGE, and pulse-Pi uptake experiments to study the regulation of Pi uptake. In high Pi medium, PhoU2 serves as the master negative regulator of Pst2 transporter function and PnpR~P levels (post-transcriptionally). ΔphoU2 mutants have high PnpR~P levels and induction of the pst1 operon, poor growth, and sensitivity to antibiotics, possibly due to high Pi accumulation. In low Pi medium, Pst2 is still active, but PnpR~P amount and pst1 operon levels increase. Together, these results support a model in which pneumococcus maintains high Pi transport in high and low Pi conditions that is required for optimal capsule biosynthesis. PMID:27379215

  14. A vacuolar phosphate transporter essential for phosphate homeostasis in Arabidopsis

    PubMed Central

    Liu, Jinlong; Yang, Lei; Luan, Mingda; Wang, Yuan; Zhang, Chi; Zhang, Bin; Shi, Jisen; Zhao, Fu-Geng; Lan, Wenzhi; Luan, Sheng

    2015-01-01

    Inorganic phosphate (Pi) is stored in the vacuole, allowing plants to adapt to variable Pi availability in the soil. The transporters that mediate Pi sequestration into vacuole remain unknown, however. Here we report the functional characterization of Vacuolar Phosphate Transporter 1 (VPT1), an SPX domain protein that transports Pi into the vacuole in Arabidopsis. The vpt1 mutant plants were stunted and consistently retained less Pi than wild type plants, especially when grown in medium containing high levels of Pi. In seedlings, VPT1 was expressed primarily in younger tissues under normal conditions, but was strongly induced by high-Pi conditions in older tissues, suggesting that VPT1 functions in Pi storage in young tissues and in detoxification of high Pi in older tissues. As a result, disruption of VPT1 rendered plants hypersensitive to both low-Pi and high-Pi conditions, reducing the adaptability of plants to changing Pi availability. Patch-clamp analysis of isolated vacuoles showed that the Pi influx current was severely reduced in vpt1 compared with wild type plants. When ectopically expressed in Nicotiana benthamiana mesophyll cells, VPT1 mediates vacuolar influx of anions, including Pi, SO42−, NO3−, Cl−, and malate with Pi as that preferred anion. The VPT1-mediated Pi current amplitude was dependent on cytosolic phosphate concentration. Single-channel analysis showed that the open probability of VPT1 was increased with the increase in transtonoplast potential. We conclude that VPT1 is a transporter responsible for vacuolar Pi storage and is essential for Pi adaptation in Arabidopsis. PMID:26554016

  15. A vacuolar phosphate transporter essential for phosphate homeostasis in Arabidopsis.

    PubMed

    Liu, Jinlong; Yang, Lei; Luan, Mingda; Wang, Yuan; Zhang, Chi; Zhang, Bin; Shi, Jisen; Zhao, Fu-Geng; Lan, Wenzhi; Luan, Sheng

    2015-11-24

    Inorganic phosphate (Pi) is stored in the vacuole, allowing plants to adapt to variable Pi availability in the soil. The transporters that mediate Pi sequestration into vacuole remain unknown, however. Here we report the functional characterization of Vacuolar Phosphate Transporter 1 (VPT1), an SPX domain protein that transports Pi into the vacuole in Arabidopsis. The vpt1 mutant plants were stunted and consistently retained less Pi than wild type plants, especially when grown in medium containing high levels of Pi. In seedlings, VPT1 was expressed primarily in younger tissues under normal conditions, but was strongly induced by high-Pi conditions in older tissues, suggesting that VPT1 functions in Pi storage in young tissues and in detoxification of high Pi in older tissues. As a result, disruption of VPT1 rendered plants hypersensitive to both low-Pi and high-Pi conditions, reducing the adaptability of plants to changing Pi availability. Patch-clamp analysis of isolated vacuoles showed that the Pi influx current was severely reduced in vpt1 compared with wild type plants. When ectopically expressed in Nicotiana benthamiana mesophyll cells, VPT1 mediates vacuolar influx of anions, including Pi, SO4(2-), NO3(-), Cl(-), and malate with Pi as that preferred anion. The VPT1-mediated Pi current amplitude was dependent on cytosolic phosphate concentration. Single-channel analysis showed that the open probability of VPT1 was increased with the increase in transtonoplast potential. We conclude that VPT1 is a transporter responsible for vacuolar Pi storage and is essential for Pi adaptation in Arabidopsis. PMID:26554016

  16. Reducing the Genetic Redundancy of Arabidopsis PHOSPHATE TRANSPORTER1 Transporters to Study Phosphate Uptake and Signaling1[OPEN

    PubMed Central

    Ayadi, Amal; David, Pascale; Arrighi, Jean-François; Chiarenza, Serge; Thibaud, Marie-Christine; Nussaume, Laurent; Marin, Elena

    2015-01-01

    Arabidopsis (Arabidopsis thaliana) absorbs inorganic phosphate (Pi) from the soil through an active transport process mediated by the nine members of the PHOSPHATE TRANSPORTER1 (PHT1) family. These proteins share a high level of similarity (greater than 61%), with overlapping expression patterns. The resulting genetic and functional redundancy prevents the analysis of their specific roles. To overcome this difficulty, our approach combined several mutations with gene silencing to inactivate multiple members of the PHT1 family, including a cluster of genes localized on chromosome 5 (PHT1;1, PHT1;2, and PHT1;3). Physiological analyses of these lines established that these three genes, along with PHT1;4, are the main contributors to Pi uptake. Furthermore, PHT1;1 plays an important role in translocation from roots to leaves in high phosphate conditions. These genetic tools also revealed that some PHT1 transporters likely exhibit a dual affinity for phosphate, suggesting that their activity is posttranslationally controlled. These lines display significant phosphate deficiency-related phenotypes (e.g. biomass and yield) due to a massive (80%–96%) reduction in phosphate uptake activities. These defects limited the amount of internal Pi pool, inducing compensatory mechanisms triggered by the systemic Pi starvation response. Such reactions have been uncoupled from PHT1 activity, suggesting that systemic Pi sensing is most probably acting downstream of PHT1. PMID:25670816

  17. The nature of the link between potassium transport and phosphate transport in Escherichia coli.

    PubMed Central

    Russell, L M; Rosenberg, H

    1980-01-01

    A series of mutants of Escherichia coli, combining defects in either of the two phosphate transport systems with defects in one or more of the potassium transport systems, was used to study the nature of the previously observed obligatory requirement for each one of these ions in the transport of the other. The results show that no pair of systems is obligatorily linked, and that either ion can be transported by any one of its systems, provided that a means of entry for the other ion is available. Furthermore, in the total absence of Pi, K+ entry accompanies the transport of other anions, such as aspartate, glutamate, sn-glycero-3-phosphate and glucose 6-phosphate. The results indicate that Pi and the other anions enter by symport with protons, and that a simultaneous K+/H+ exchange, which would serve to maintain the intracellular pH, is responsible for the observed K+ 'symport' with these anions. PMID:6258560

  18. The yeast Aft2 transcription factor determines selenite toxicity by controlling the low affinity phosphate transport system.

    PubMed

    Pérez-Sampietro, María; Serra-Cardona, Albert; Canadell, David; Casas, Celia; Ariño, Joaquín; Herrero, Enrique

    2016-01-01

    The yeast Saccharomyces cerevisiae is employed as a model to study the cellular mechanisms of toxicity and defense against selenite, the most frequent environmental selenium form. We show that yeast cells lacking Aft2, a transcription factor that together with Aft1 regulates iron homeostasis, are highly sensitive to selenite but, in contrast to aft1 mutants, this is not rescued by iron supplementation. The absence of Aft2 strongly potentiates the transcriptional responses to selenite, particularly for DNA damage- and oxidative stress-responsive genes, and results in intracellular hyperaccumulation of selenium. Overexpression of PHO4, the transcriptional activator of the PHO regulon under low phosphate conditions, partially reverses sensitivity and hyperaccumulation of selenite in a way that requires the presence of Spl2, a Pho4-controlled protein responsible for post-transcriptional downregulation of the low-affinity phosphate transporters Pho87 and Pho90. SPL2 expression is strongly downregulated in aft2 cells, especially upon selenite treatment. Selenite hypersensitivity of aft2 cells is fully rescued by deletion of PHO90, suggesting a major role for Pho90 in selenite uptake. We propose that the absence of Aft2 leads to enhanced Pho90 function, involving both Spl2-dependent and independent events and resulting in selenite hyperaccumulation and toxicity. PMID:27618952

  19. Mutational analysis of the Escherichia coli phosphate-specific transport system, a member of the traffic ATPase (or ABC) family of membrane transporters. A role for proline residues in transmembrane helices.

    PubMed

    Webb, D C; Rosenberg, H; Cox, G B

    1992-12-01

    The Escherichia coli Pst system is a periplasmic phosphate permease. A mutational analysis of the requirement for function of specific charged residues or proline residues in the two hydrophobic subunits (PstC and PstA) has been carried out. No residues, among 19 charged residues altered, were found to be essential for phosphate uptake, although some alterations resulted in partial effects. Evidence was obtained that the 3 residues, R220 in the PstA protein and R237 and E241 in the PstC protein, previously shown to be required for phosphate transport (Cox, G. B., Webb, D., Godovac-Zimmermann, J., and Rosenberg, H. (1988) J. Bacteriol. 170, 2283-2286; Cox, G. B., Webb, D., and Rosenberg, H. (1989) J. Bacteriol. 171, 1531-1534), interact with each other. A feature of the proposed structures of the PstA and PstC proteins was 2 pairs of proline residues in putative transmembrane helices 3 and 4. While individual substitutions of these proline residues by leucine resulted in loss of phosphate transport activity substitution by alanine only had partial effects. However, if the proline to alanine changes were paired then, depending on the particular subunit, markedly different effects were obtained. The double mutation in the PstA protein resulted in a permanently "closed" system, whereas the double mutation in the PstC protein resulted in a permanently "open" transport system. PMID:1447208

  20. Sorbitol production from lactose by engineered Lactobacillus casei deficient in sorbitol transport system and mannitol-1-phosphate dehydrogenase.

    PubMed

    De Boeck, Reinout; Sarmiento-Rubiano, Luz Adriana; Nadal, Inmaculada; Monedero, Vicente; Pérez-Martínez, Gaspar; Yebra, María J

    2010-02-01

    Sorbitol is a sugar alcohol largely used in the food industry as a low-calorie sweetener. We have previously described a sorbitol-producing Lactobacillus casei (strain BL232) in which the gutF gene, encoding a sorbitol-6-phosphate dehydrogenase, was expressed from the lactose operon. Here, a complete deletion of the ldh1 gene, encoding the main L-lactate dehydrogenase, was performed in strain BL232. In a resting cell system with glucose, the new strain, named BL251, accumulated sorbitol in the medium that was rapidly metabolized after glucose exhaustion. Reutilization of produced sorbitol was prevented by deleting the gutB gene of the phosphoenolpyruvate: sorbitol phosphotransferase system (PTS(Gut)) in BL251. These results showed that the PTS(Gut) did not mediate sorbitol excretion from the cells, but it was responsible for uptake and reutilization of the synthesized sorbitol. A further improvement in sorbitol production was achieved by inactivation of the mtlD gene, encoding a mannitol-1-phosphate dehydrogenase. The new strain BL300 (lac::gutF Deltaldh1 DeltagutB mtlD) showed an increase in sorbitol production whereas no mannitol synthesis was detected, avoiding thus a polyol mixture. This strain was able to convert lactose, the main sugar from milk, into sorbitol, either using a resting cell system or in growing cells under pH control. A conversion rate of 9.4% of lactose into sorbitol was obtained using an optimized fed-batch system and whey permeate, a waste product of the dairy industry, as substrate. PMID:19784641

  1. Regulation of hormone-sensitive renal phosphate transport.

    PubMed

    Gattineni, Jyothsna; Friedman, Peter A

    2015-01-01

    Phosphate is essential for growth and maintenance of the skeleton and for generating high-energy phosphate compounds. Evolutionary adaptation to high dietary phosphorous in humans and other terrestrial vertebrates involves regulated mechanisms assuring the efficient renal elimination of excess phosphate. These mechanisms prominently include PTH, FGF23, and Vitamin D, which directly and indirectly regulate phosphate transport. Disordered phosphate homeostasis is associated with pathologies ranging from kidney stones to kidney failure. Chronic kidney disease results in hyperphosphatemia, an elevated calcium×phosphate product with considerable morbidity and mortality, mostly associated with adverse cardiovascular events. This chapter highlights recent findings and insights regarding the hormonal regulation of renal phosphate transport along with imbalances of phosphate balance due to acquired or inherited diseases states. PMID:25817872

  2. Transport and signaling through the phosphate-binding site of the yeast Pho84 phosphate transceptor.

    PubMed

    Popova, Yulia; Thayumanavan, Palvannan; Lonati, Elena; Agrochão, Margarida; Thevelein, Johan M

    2010-02-16

    A novel concept in eukaryotic signal transduction is the use of nutrient transporters and closely related proteins as nutrient sensors. The action mechanism of these "transceptors" is unclear. The Pho84 phosphate transceptor in yeast transports phosphate and mediates rapid phosphate activation of the protein kinase A (PKA) pathway during growth induction. We have now identified several phosphate-containing compounds that act as nontransported signaling agonists of Pho84. This indicates that signaling does not require complete transport of the substrate. For the nontransported agonist glycerol-3-phosphate (Gly3P), we show that it is transported by two other carriers, Git1 and Pho91, without triggering signaling. Gly3P is a competitive inhibitor of transport through Pho84, indicating direct interaction with its phosphate-binding site. We also identified phosphonoacetic acid as a competitive inhibitor of transport without agonist function for signaling. This indicates that binding of a compound into the phosphate-binding site of Pho84 is not enough to trigger signaling. Apparently, signaling requires a specific conformational change that may be part of, but does not require, the complete transport cycle. Using Substituted Cysteine Accessibility Method (SCAM) we identified Phe(160) in TMD IV and Val(392) in TMD VIII as residues exposed with their side chain into the phosphate-binding site of Pho84. Inhibition of both transport and signaling by covalent modification of Pho84(F160C) or Pho84(V392C) showed that the same binding site is used for transport of phosphate and for signaling with both phosphate and Gly3P. Our results provide to the best of our knowledge the first insight into the molecular mechanism of a phosphate transceptor. PMID:20133652

  3. Vacuolar Ca2+/H+ Transport Activity Is Required for Systemic Phosphate Homeostasis Involving Shoot-to-Root Signaling in Arabidopsis1[W][OA

    PubMed Central

    Liu, Tzu-Yin; Aung, Kyaw; Tseng, Ching-Ying; Chang, Tzu-Yun; Chen, Ying-Shin; Chiou, Tzyy-Jen

    2011-01-01

    Calcium ions (Ca2+) and Ca2+-related proteins mediate a wide array of downstream processes involved in plant responses to abiotic stresses. In Arabidopsis (Arabidopsis thaliana), disruption of the vacuolar Ca2+/H+ transporters CAX1 and CAX3 causes notable alterations in the shoot ionome, including phosphate (Pi) content. In this study, we showed that the cax1/cax3 double mutant displays an elevated Pi level in shoots as a result of increased Pi uptake in a miR399/PHO2-independent signaling pathway. Microarray analysis of the cax1/cax3 mutant suggests the regulatory function of CAX1 and CAX3 in suppressing the expression of a subset of shoot Pi starvation-responsive genes, including genes encoding the PHT1;4 Pi transporter and two SPX domain-containing proteins, SPX1 and SPX3. Moreover, although the expression of several PHT1 genes and PHT1;1/2/3 proteins is not up-regulated in the root of cax1/cax3, results from reciprocal grafting experiments indicate that the cax1/cax3 scion is responsible for high Pi accumulation in grafted plants and that the pht1;1 rootstock is sufficient to moderately repress such Pi accumulation. Based on these findings, we propose that CAX1 and CAX3 mediate a shoot-derived signal that modulates the activity of the root Pi transporter system, likely in part via posttranslational regulation of PHT1;1 Pi transporters. PMID:21546457

  4. Sodium-Dependent Phosphate Transporters in Osteoclast Differentiation and Function

    PubMed Central

    Dolder, Silvia; Siegrist, Mark; Wagner, Carsten A.; Biber, Jürg; Hernando, Nati; Hofstetter, Willy

    2015-01-01

    Osteoclasts are multinucleated bone degrading cells. Phosphate is an important constituent of mineralized bone and released in significant quantities during bone resorption. Molecular contributors to phosphate transport during the resorptive activity of osteoclasts have been controversially discussed. This study aimed at deciphering the role of sodium-dependent phosphate transporters during osteoclast differentiation and bone resorption. Our studies reveal RANKL-induced differential expression of sodium-dependent phosphate transport protein IIa (NaPi-IIa) transcript and protein during osteoclast development, but no expression of the closely related NaPi-IIb and NaPi-IIc SLC34 family isoforms. In vitro studies employing NaPi-IIa-deficient osteoclast precursors and mature osteoclasts reveal that NaPi-IIa is dispensable for bone resorption and osteoclast differentiation. These results are supported by the analysis of structural bone parameters by high-resolution microcomputed tomography that yielded no differences between adult NaPi-IIa WT and KO mice. By contrast, both type III sodium-dependent phosphate transporters Pit-1 and Pit-2 were abundantly expressed throughout osteoclast differentiation, indicating that they are the relevant sodium-dependent phosphate transporters in osteoclasts and osteoclast precursors. We conclude that phosphate transporters of the SLC34 family have no role in osteoclast differentiation and function and propose that Pit-dependent phosphate transport could be pivotal for bone resorption and should be addressed in further studies. PMID:25910236

  5. Vacuolar SPX-MFS transporters are essential for phosphate adaptation in plants.

    PubMed

    Liu, Jinlong; Fu, Shaomin; Yang, Lei; Luan, Mingda; Zhao, Fugeng; Luan, Sheng; Lan, Wenzhi

    2016-08-01

    To survive in most soils in which inorganic phosphate (Pi) levels are limited and constantly changing, plants universally use the vacuoles as cellular Pi "sink" and "source" to maintain Pi homeostasis. However, the transporters that mediate Pi sequestration into the vacuoles remain unknown. Recently, we and other 2 groups independently identified the members of SPS-MSF family as the candidates for tonoplast Pi transporters in Arabidopsis thaliana and Oryza sativa. We and Liu et al. demonstrated that one of SPS-MSF member, VPT1 (Vacuolar Phosphate Transporter 1), also named as PHT5;1 (Phosphate Transporter 5;1), plays a predominant role in Pi sequestration of vacuoles in Arabidopsis. Here we show that vpt1 mutants and VPT1-GFP overexpressing lines displayed sensitive to Pi stress under the hydroponic system containing the medium with low iron, supporting that VPT1 is essential for Arabidopsis to adapt phosphate stress. PMID:27467463

  6. Organophosphate Hydrolase Is a Lipoprotein and Interacts with Pi-specific Transport System to Facilitate Growth of Brevundimonas diminuta Using OP Insecticide as Source of Phosphate.

    PubMed

    Parthasarathy, Sunil; Parapatla, Hari; Nandavaram, Aparna; Palmer, Tracy; Siddavattam, Dayananda

    2016-04-01

    Organophosphate hydrolase (OPH), encoded by the organophosphate degradation (opd) island, hydrolyzes the triester bond found in a variety of organophosphate insecticides and nerve agents. OPH is targeted to the inner membrane ofBrevundimonas diminutain a pre-folded conformation by thetwinargininetransport (Tat) pathway. The OPH signal peptide contains an invariant cysteine residue at the junction of the signal peptidase (Spase) cleavage site along with a well conserved lipobox motif. Treatment of cells producing native OPH with the signal peptidase II inhibitor globomycin resulted in accumulation of most of the pre-OPH in the cytoplasm with negligible processed OPH detected in the membrane. Substitution of the conserved lipobox cysteine to serine resulted in release of OPH into the periplasm, confirming that OPH is a lipoprotein. Analysis of purified OPH revealed that it was modified with the fatty acids palmitate and stearate. Membrane-bound OPH was shown to interact with the outer membrane efflux protein TolC and with PstS, the periplasmic component of the ABC transporter complex (PstSACB) involved in phosphate transport. Interaction of OPH with PstS appears to facilitate transport of Pigenerated from organophosphates due to the combined action of OPH and periplasmically located phosphatases. Consistent with this model,opdnull mutants ofB. diminutafailed to grow using the organophosphate insecticide methyl parathion as sole source of phosphate. PMID:26861877

  7. A phosphate transporter from the mycorrhizal fungus Glomus versiforme.

    PubMed

    Harrison, M J; van Buuren, M L

    1995-12-01

    Vesicular-arbuscular (VA) mycorrhizal fungi form symbiotic associations with the roots of most terrestrial plants, including many agriculturally important crop species. The fungi colonize the cortex of the root to obtain carbon from their plant host, while assisting the plant with the uptake of phosphate and other mineral nutrients from the soil. This association is beneficial to the plant, because phosphate is essential for plant growth and development, especially during growth under nutrient-limiting conditions. Molecular genetic studies of these fungi and their interaction with plants have been limited owing to the obligate symbiotic nature of the VA fungi, so the molecular mechanisms underlying fungal-mediated uptake and translocation of phosphate from the soil to the plant remain unknown. Here we begin to investigate this process by identifying a complementary DNA that encodes a transmembrane phosphate transporter (GvPT) from Glomus versiforme, a VA mycorrhizal fungus. The function of the protein encoded by GvPT was confirmed by complementation of a yeast phosphate transport mutant. Expression of GvPT was localized to the external hyphae of G. versiforme during mycorrhizal associations, these being the initial site of phosphate uptake from the soil. PMID:8524398

  8. The Phosphate Transporter from Pea Mitochondria (Isolation and Characterization in Proteolipid Vesicles).

    PubMed Central

    McIntosh, C. A.; Oliver, D. J.

    1994-01-01

    The phosphate transporter from mitochondria will exchange matrix phosphate for cytosolic phosphate and facilitate either phosphate/proton symport or phosphate/hydroxyl ion antiport. The phosphate transported into the matrix by this carrier is either used for ATP synthesis or exchanges back out to the cytosol on the dicarboxylate transporter, permitting entry of malate and succinate into the matrix. The phosphate transporter was solubilized from etiolated pea (Pisum sativum L. cv Alaska) mitochondrial membranes with Triton X-114, purified approximately 500-fold by hydroxylapatite chromatography, and reconstituted into azolectin vesicles that were preloaded with 0.1 or 10 mM phosphate. Phosphate transport was measured as the exchange of preloaded phosphate for external [32P]phosphate. Phosphate/phosphate exchange occurred for over 40 min at room temperature with an apparent K0.5 of 1.6 mM and a maximum velocity of over 700 nmol (mg protein)-1 min-1. Diethyl pyrocarbonate was used as an inhibitor-stop reagent. Transport was inhibited by p-hydroxyphenylglyoxal, p-hydroxymercuribenzoate, pyridoxal 5-phosphate, and dansyl chloride but was insensitive to sulfate, nitrate, and N-ethylmaleimide, the standard inhibitor for the mammalian phosphate transporter. Phosphate/hydroxyl exchange was stimulated when the proton gradient was collapsed with carbonyl cyanide m-chlorophenylhydrazone, but phosphate/phosphate exchange was unaffected by the uncoupler. PMID:12232184

  9. Phosphate transporters from the higher plant Arabidopsis thaliana.

    PubMed Central

    Muchhal, U S; Pardo, J M; Raghothama, K G

    1996-01-01

    Two cDNAs (AtPT1 and AtPT2) encoding plant phosphate transporters have been isolated from a library prepared with mRNA extracted from phosphate-starved Arabidopsis thaliana roots, The encoded polypeptides are 78% identical to each other and show high degree of amino acid sequence similarity with high-affinity phosphate transporters of Saccharomyces cerevisiae, Neurospora crassa, and the mycorrhizal fungus Glomus versiforme. The AtPT1 and AtPT2 polypeptides are integral membrane proteins predicted to contain 12 membrane-spanning domains separated into two groups of six by a large charged hydrophilic region. Upon expression, both AtPT1 and AtPT2 were able to complement the pho84 mutant phenotype of yeast strain NS219 lacking the high-affinity phosphate transport activity. AtPT1 and AtPT2 are representatives of two distinct, small gene families in A. thaliana. The transcripts of both genes are expressed in roots and are not detectable in leaves. The steady-state level of their mRNAs increases in response to phosphate starvation. Images Fig. 3 Fig. 4 Fig. 5 PMID:8927627

  10. An alternative membrane transport pathway for phosphate and adenine nucleotides in mitochondria and its possible function.

    PubMed

    Reynafarje, B; Lehninger, A L

    1978-10-01

    This paper describes the properties and a possible biological role of a transport process across the inner membrane of rat liver mitochondria resulting in the exchange of ATP(4-) (out) for ADP(3-) (in) + 0.5 phosphate(2-) (in). This transmembrane exchange reaction, designated as the ATP-ADP-phosphate exchange, is specific for the ligands shown, electroneutral, insensitive to N-ethylmaleimide or mersalyl, inhibited by atractyloside, and appears to occur only in the direction as written. It is thus distinct from the well-known phosphate-hydroxide and phosphate-dicarboxylate exchange systems, which are inhibited by mersalyl, and from the ATP-ADP exchanger, which does not transport phosphate. During ATP hydrolysis by mitochondria, half of the phosphate formed from ATP passes from the matrix to the medium by the mersalyl-insensitive ATP-ADP-phosphate exchange and the other half by the well-known mersalyl-sensitive phosphate-hydroxide exchange. These and other considerations have led to a hypothesis for the pathway and stoichiometry of ATP-dependent reverse electron transport, characterized by a requirement of 1.33 molecules of ATP per pair of electrons reversed and by the utilization of a different membrane transport pathway for phosphate and adenine nucleotides than is taken in forward electron flow and oxidative phosphorylation. The possible occurrence of independent pathways for ATP-forming forward electron flow and ATP-consuming reverse electron flow is consonant with the fact that the opposing degradative and synthetic pathways in the central routes of cell metabolism generally have different pathways that are independently regulated. PMID:283393

  11. Phosphate Import in Plants: Focus on the PHT1 Transporters

    PubMed Central

    Nussaume, Laurent; Kanno, Satomi; Javot, Hélène; Marin, Elena; Pochon, Nathalie; Ayadi, Amal; Nakanishi, Tomoko M.; Thibaud, Marie-Christine

    2011-01-01

    The main source of phosphorus for plants is inorganic phosphate (Pi), which is characterized by its poor availability and low mobility. Uptake of this element from the soil relies heavily upon the PHT1 transporters, a specific family of plant plasma membrane proteins that were identified by homology with the yeast PHO84 Pi transporter. Since the discovery of PHT1 transporters in 1996, various studies have revealed that their function is controlled by a highly complex network of regulation. This review will summarize the current state of research on plant PHT1 multigenic families, including physiological, biochemical, molecular, cellular, and genetics studies. PMID:22645553

  12. Atomic-level characterization of transport cycle thermodynamics in the glycerol-3-phosphate:phosphate antiporter

    NASA Astrophysics Data System (ADS)

    Moradi, Mahmoud; Enkavi, Giray; Tajkhorshid, Emad

    2015-09-01

    Membrane transporters actively translocate their substrate by undergoing large-scale structural transitions between inward- (IF) and outward-facing (OF) states (`alternating-access' mechanism). Despite extensive structural studies, atomic-level mechanistic details of such structural transitions, and as importantly, their coupling to chemical events supplying the energy, remain amongst the most elusive aspects of the function of these proteins. Here we present a quantitative, atomic-level description of the functional thermodynamic cycle for the glycerol-3-phosphate:phosphate antiporter GlpT by using a novel approach in reconstructing the free energy landscape governing the IF<-->OF transition along a cyclic transition pathway involving both apo and substrate-bound states. Our results provide a fully atomic description of the complete transport process, offering a structural model for the alternating-access mechanism and substantiating the close coupling between global structural transitions and local chemical events.

  13. Atomic-level characterization of transport cycle thermodynamics in the glycerol-3-phosphate:phosphate antiporter

    PubMed Central

    Moradi, Mahmoud; Enkavi, Giray; Tajkhorshid, Emad

    2015-01-01

    Membrane transporters actively translocate their substrate by undergoing large-scale structural transitions between inward- (IF) and outward-facing (OF) states (‘alternating-access' mechanism). Despite extensive structural studies, atomic-level mechanistic details of such structural transitions, and as importantly, their coupling to chemical events supplying the energy, remain amongst the most elusive aspects of the function of these proteins. Here we present a quantitative, atomic-level description of the functional thermodynamic cycle for the glycerol-3-phosphate:phosphate antiporter GlpT by using a novel approach in reconstructing the free energy landscape governing the IF↔OF transition along a cyclic transition pathway involving both apo and substrate-bound states. Our results provide a fully atomic description of the complete transport process, offering a structural model for the alternating-access mechanism and substantiating the close coupling between global structural transitions and local chemical events. PMID:26417850

  14. Identification of plant vacuolar transporters mediating phosphate storage

    PubMed Central

    Liu, Tzu-Yin; Huang, Teng-Kuei; Yang, Shu-Yi; Hong, Yu-Ting; Huang, Sheng-Min; Wang, Fu-Nien; Chiang, Su-Fen; Tsai, Shang-Yueh; Lu, Wen-Chien; Chiou, Tzyy-Jen

    2016-01-01

    Plant vacuoles serve as the primary intracellular compartments for inorganic phosphate (Pi) storage. Passage of Pi across vacuolar membranes plays a critical role in buffering the cytoplasmic Pi level against fluctuations of external Pi and metabolic activities. Here we demonstrate that the SPX-MFS proteins, designated as PHOSPHATE TRANSPORTER 5 family (PHT5), also named Vacuolar Phosphate Transporter (VPT), function as vacuolar Pi transporters. Based on 31P-magnetic resonance spectroscopy analysis, Arabidopsis pht5;1 loss-of-function mutants accumulate less Pi and exhibit a lower vacuolar-to-cytoplasmic Pi ratio than controls. Conversely, overexpression of PHT5 leads to massive Pi sequestration into vacuoles and altered regulation of Pi starvation-responsive genes. Furthermore, we show that heterologous expression of the rice homologue OsSPX-MFS1 mediates Pi influx to yeast vacuoles. Our findings show that a group of Pi transporters in vacuolar membranes regulate cytoplasmic Pi homeostasis and are required for fitness and plant growth. PMID:27029856

  15. Identification of plant vacuolar transporters mediating phosphate storage.

    PubMed

    Liu, Tzu-Yin; Huang, Teng-Kuei; Yang, Shu-Yi; Hong, Yu-Ting; Huang, Sheng-Min; Wang, Fu-Nien; Chiang, Su-Fen; Tsai, Shang-Yueh; Lu, Wen-Chien; Chiou, Tzyy-Jen

    2016-01-01

    Plant vacuoles serve as the primary intracellular compartments for inorganic phosphate (Pi) storage. Passage of Pi across vacuolar membranes plays a critical role in buffering the cytoplasmic Pi level against fluctuations of external Pi and metabolic activities. Here we demonstrate that the SPX-MFS proteins, designated as PHOSPHATE TRANSPORTER 5 family (PHT5), also named Vacuolar Phosphate Transporter (VPT), function as vacuolar Pi transporters. Based on (31)P-magnetic resonance spectroscopy analysis, Arabidopsis pht5;1 loss-of-function mutants accumulate less Pi and exhibit a lower vacuolar-to-cytoplasmic Pi ratio than controls. Conversely, overexpression of PHT5 leads to massive Pi sequestration into vacuoles and altered regulation of Pi starvation-responsive genes. Furthermore, we show that heterologous expression of the rice homologue OsSPX-MFS1 mediates Pi influx to yeast vacuoles. Our findings show that a group of Pi transporters in vacuolar membranes regulate cytoplasmic Pi homeostasis and are required for fitness and plant growth. PMID:27029856

  16. Polaronic Transport in Phosphate Glasses Containing Transition Metal Ions

    NASA Astrophysics Data System (ADS)

    Henderson, Mark

    The goal of this dissertation is to characterize the basic transport properties of phosphate glasses containing various amounts of TIs and to identify and explain any electronic phase transitions which may occur. The P2 O5-V2O5-WO3 (PVW) glass system will be analyzed to find the effect of TI concentration on conduction. In addition, the effect of the relative concentrations of network forming ions (SiO2 and P2O5) on transport will be studied in the P2O5-SiO2-Fe2O 3 (PSF) system. Also presented is a numerical study on a tight-binding model adapted for the purposes of modelling Gaussian traps, mimicking TI's, which are arranged in an extended network. The results of this project will contribute to the development of fundamental theories on the electronic transport in glasses containing mixtures of transition oxides as well as those containing multiple network formers without discernible phase separation. The present study on the PVW follows up on previous investigation into the effect on mixed transition ions in oxide glasses. Past research has focused on glasses containing transition metal ions from the 3d row. The inclusion of tungsten, a 5d transition metal, adds a layer of complexity through the mismatch of the energies of the orbitals contributing to localized states. The data have indicated that a transition reminiscent of a metal-insulator transition (MIT) occurs in this system as the concentration of tungsten increases. As opposed to some other MIT-like transitions found in phosphate glass systems, there seems to be no polaron to bipolaron conversion. Instead, the individual localization parameter for tungsten noticeably decreases dramatically at the transition point as well as the adiabaticity. Another distinctive feature of this project is the study of the PSF system, which contains two true network formers, phosphorous pentoxide (P2O 5) and silicon dioxide (SiO2). It is not usually possible to do a reliable investigation of the conduction properties of

  17. Arsenate transport by sodium/phosphate cotransporter type IIb

    SciTech Connect

    Villa-Bellosta, Ricardo; Sorribas, Victor

    2010-08-15

    Arsenic is a metalloid that causes the dysfunction of critical enzymes, oxidative stress, and malignancies. In recent years several transporters of As{sup III} have been identified, including aquaglyceroporins (AQP) and multidrug resistance proteins (MRP). As{sup V} transport, however, has not been sufficiently studied because it has been assumed that arsenate is taken up by mammalian cells through inorganic phosphate (Pi) transporters. In this paper we have analyzed the role of Pi transporters in the uptake of arsenate by directly using {sup 73}As{sup V} as a radiotracer in phosphate transporter-expressing Xenopus laevis oocytes. The affinities of Pi transporters for H{sub 3}AsO{sub 4} were lower than the affinities for Pi. NaPiIIa, NaPiIIc, Pit1, and Pit2 showed a K{sub m} for arsenate that was > 1 mM (i.e., at least ten times lower than the affinities for Pi). The NaPiIIb isoform showed the highest affinity for As{sup V} in mouse (57 {mu}M), rat (51 {mu}M), and human (9.7 {mu}M), which are very similar to the affinities for Pi. Therefore, NaPiIIb can have a prominent role in the toxicokinetics of arsenic following oral exposure to freshwater or food contaminated with As{sup V}.

  18. The rice CK2 kinase regulates trafficking of phosphate transporters in response to phosphate levels.

    PubMed

    Chen, Jieyu; Wang, Yifeng; Wang, Fei; Yang, Jian; Gao, Mingxing; Li, Changying; Liu, Yingyao; Liu, Yu; Yamaji, Naoki; Ma, Jian Feng; Paz-Ares, Javier; Nussaume, Laurent; Zhang, Shuqun; Yi, Keke; Wu, Zhongchang; Wu, Ping

    2015-03-01

    Phosphate transporters (PTs) mediate phosphorus uptake and are regulated at the transcriptional and posttranslational levels. In one key mechanism of posttranslational regulation, phosphorylation of PTs affects their trafficking from the endoplasmic reticulum (ER) to the plasma membrane. However, the kinase(s) mediating PT phosphorylation and the mechanism leading to ER retention of phosphorylated PTs remain unclear. In this study, we identified a rice (Oryza sativa) kinase subunit, CK2β3, which interacts with PT2 and PT8 in a yeast two-hybrid screen. Also, the CK2α3/β3 holoenzyme phosphorylates PT8 under phosphate-sufficient conditions. This phosphorylation inhibited the interaction of PT8 with PHOSPHATE TRANSPORTER TRAFFIC FACILITATOR1, a key cofactor regulating the exit of PTs from the ER to the plasma membrane. Additionally, phosphorus starvation promoted CK2β3 degradation, relieving the negative regulation of PT phosphorus-insufficient conditions. In accordance, transgenic expression of a nonphosphorylatable version of OsPT8 resulted in elevated levels of that protein at the plasma membrane and enhanced phosphorus accumulation and plant growth under various phosphorus regimes. Taken together, these results indicate that CK2α3/β3 negatively regulates PTs and phosphorus status regulates CK2α3/β3. PMID:25724641

  19. Na+-independent phosphate transport in Caco2BBE cells

    PubMed Central

    Candeal, Eduardo; Caldas, Yupanqui A.; Guillén, Natalia; Levi, Moshe

    2014-01-01

    Pi transport in epithelia has both Na+-dependent and Na+-independent components, but so far only Na+-dependent transporters have been characterized in detail and molecularly identified. Consequently, in the present study, we initiated the characterization and analysis of intestinal Na+-independent Pi transport using an in vitro model, Caco2BBE cells. Only Na+-independent Pi uptake was observed in these cells, and Pi uptake was dramatically increased when cells were incubated in high-Pi DMEM (4 mM) from 1 day to several days. No response to low-Pi medium was observed. The increased Pi transport was mainly caused by Vmax changes, and it was prevented by actinomycin D and cycloheximide. Pi transport in cells grown in 1 mM Pi (basal DMEM) decreased at pH > 7.5, and it was inhibited with proton ionophores. Pi transport in cells incubated with 4 mM Pi increased with alkaline pH, suggesting a preference for divalent phosphate. Pi uptake in cells in 1 mM Pi was completely inhibited only by Pi and partially inhibited by phosphonoformate, oxalate, DIDS, SITS, SO42−, HCO3−, and arsenate. This inhibition pattern suggests that more than one Pi transporter is active in cells maintained with 1 mM Pi. Phosphate transport from cells maintained at 4 mM Pi was only partially inhibited by phosphonoformate, oxalate, and arsenate. Attempts to identify the responsible transporters showed that multifunctional anion exchangers of the Slc26 family as well as members of Slc17, Slc20, and Slc37 and the Pi exporter xenotropic and polytropic retrovirus receptor 1 are not involved. PMID:25298422

  20. Faropenem Transport across the Renal Epithelial Luminal Membrane via Inorganic Phosphate Transporter Npt1

    PubMed Central

    Uchino, Hiroshi; Tamai, Ikumi; Yabuuchi, Hikaru; China, Kayoko; Miyamoto, Ken-ichi; Takeda, Eiji; Tsuji, Akira

    2000-01-01

    We previously showed that the mouse inorganic phosphate transporter Npt1 operates in the hepatic sinusoidal membrane transport of anionic drugs such as benzylpenicillin and mevalonic acid. In the present study, the mechanism of renal secretion of penem antibiotics was examined by using a Xenopus oocyte expression system. Faropenem (an oral penem antibiotic) was transported via Npt1 with a Michaelis-Menten constant of 0.77 ± 0.34 mM in a sodium-independent but chloride ion-sensitive manner. When the concentration of chloride ions was increased, the transport activity of faropenem by Npt1 was decreased. Since the concentration gradient of chloride ions is in the lumen-to-intracellular direction, faropenem is expected to be transported from inside proximal tubular cells to the lumen. So, we tested the release of faropenem from Xenopus oocytes. The rate of efflux of faropenem from Npt1-expressing oocytes was about 9.5 times faster than that from control water-injected Xenopus oocytes. Faropenem transport by Npt1 was significantly inhibited by β-lactam antibiotics such as benzylpenicillin, ampicillin, cephalexin, and cefazolin to 24.9, 40.5, 54.4, and 26.2% of that for the control, respectively. Zwitterionic β-lactam antibiotics showed lesser inhibitory effects on faropenem uptake than anionic derivatives, indicating that Npt1 preferentially transports anionic compounds. Other anionic compounds, such as indomethacin and furosemide, and the anion transport inhibitor 4,4′-diisothiocyanostilbene-2,2′-disulfonic acid significantly inhibited faropenem uptake mediated by Npt1. In conclusion, our results suggest that Npt1 participates in the renal secretion of penem antibiotics. PMID:10681320

  1. Faropenem transport across the renal epithelial luminal membrane via inorganic phosphate transporter Npt1.

    PubMed

    Uchino, H; Tamai, I; Yabuuchi, H; China, K; Miyamoto, K; Takeda, E; Tsuji, A

    2000-03-01

    We previously showed that the mouse inorganic phosphate transporter Npt1 operates in the hepatic sinusoidal membrane transport of anionic drugs such as benzylpenicillin and mevalonic acid. In the present study, the mechanism of renal secretion of penem antibiotics was examined by using a Xenopus oocyte expression system. Faropenem (an oral penem antibiotic) was transported via Npt1 with a Michaelis-Menten constant of 0.77 +/- 0.34 mM in a sodium-independent but chloride ion-sensitive manner. When the concentration of chloride ions was increased, the transport activity of faropenem by Npt1 was decreased. Since the concentration gradient of chloride ions is in the lumen-to-intracellular direction, faropenem is expected to be transported from inside proximal tubular cells to the lumen. So, we tested the release of faropenem from Xenopus oocytes. The rate of efflux of faropenem from Npt1-expressing oocytes was about 9.5 times faster than that from control water-injected Xenopus oocytes. Faropenem transport by Npt1 was significantly inhibited by beta-lactam antibiotics such as benzylpenicillin, ampicillin, cephalexin, and cefazolin to 24.9, 40. 5, 54.4, and 26.2% of that for the control, respectively. Zwitterionic beta-lactam antibiotics showed lesser inhibitory effects on faropenem uptake than anionic derivatives, indicating that Npt1 preferentially transports anionic compounds. Other anionic compounds, such as indomethacin and furosemide, and the anion transport inhibitor 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid significantly inhibited faropenem uptake mediated by Npt1. In conclusion, our results suggest that Npt1 participates in the renal secretion of penem antibiotics. PMID:10681320

  2. Facilitated transport of anatase titanium dioxides nanoparticles in the presence of phosphate in saturated sands.

    PubMed

    Chen, Ming; Xu, Nan; Cao, Xinde; Zhou, Kairong; Chen, Zhigang; Wang, Yunlong; Liu, Cheng

    2015-08-01

    Soil and water environments are inevitably contaminated by the excess of artificial nanoparticles (NPs) and phosphorus (P) fertilizers. There is a possibility of phosphate facilitating or inhibiting the transport of nanoparticles titanium dioxides (nTiO2). It is a great urgency and high priority to investigate the nTiO2 retention mechanisms and accurately describe the transport of nTiO2 in the presence of phosphate. Anatase nTiO2 with two sizes of 20 and 50nm through the saturated porous sand columns were observed under the conditions (0-50mM NaNO3 electrolyte, influent P concentrations of 0.10mM and 2.0mM, pH 6.5 and 7.5). The experimental results show the phosphate favor the dispersion of nTiO2, and consequently improve their transport patterns. The likely mechanism is that phosphate adsorption increasing the negative charge on the surface promotes the transportability of nTiO2 resulting from the low deposition rate and attachment efficiency of NPs. In particular, the facilitated transport of nTiO2 (50nm) is greater than those relative smaller as 20nm. In addition, this enhancement of nTiO2 transportability by phosphate at pH 6.5 is increased at higher pH of 7.5 due to the more negative zeta potential of surface, which indicates the potential risks to groundwater systems. PMID:25897849

  3. Regulation of plants' phosphate uptake in common mycorrhizal networks: Role of intraradical fungal phosphate transporters.

    PubMed

    Walder, Florian; Boller, Thomas; Wiemken, Andres; Courty, Pierre-Emmanuel

    2016-01-01

    We have recently identified two genes coding for inorganic phosphate transporters (Pht) in sorghum (Sorghum bicolor) and flax (Linum usitatissimum) that were induced in roots colonized by arbuscular mycorrhizal (AM) fungi. Mycorrhizal acquisition of inorganic phosphorus (Pi) was strongly affected by the combination of plant and AM fungal species, but the expression level of these genes coding for AM-inducible Pi transporters did not explain differences in plant phosphorus acquisition where flax and sorghum are sharing a common mycorrhizal network. In the present study, we investigated the possible role of fungal Pi transporters in the regulation of mycorrhizal Pi acquisition by measuring their expression in roots of flax and sorghum. One Pi transporter of Rhizophagus irregularis (RiPT5) showed a positive correlation with mycorrhizal Pi acquisition of sorghum. This indicates that a possible involvement in the regulation of mycorrhizal Pi acquisition. In general, expression of AMF Pi transporters was more related to mycorrhizal Pi acquisition of sorghum than of flax, indicating plant species-specific differences in the regulation of mycorrhizal Pi acquisition. PMID:26751110

  4. Sphingosine-1-phosphate transporters as targets for cancer therapy.

    PubMed

    Nagahashi, Masayuki; Takabe, Kazuaki; Terracina, Krista P; Soma, Daiki; Hirose, Yuki; Kobayashi, Takashi; Matsuda, Yasunobu; Wakai, Toshifumi

    2014-01-01

    Sphingosine-1-phosphate (S1P) is a pleiotropic lipid mediator that regulates cell survival, migration, the recruitment of immune cells, angiogenesis, and lymphangiogenesis, all of which are involved in cancer progression. S1P is generated inside cancer cells by sphingosine kinases then exported outside of the cell into the tumor microenvironment where it binds to any of five G protein coupled receptors and proceeds to regulate a variety of functions. We have recently reported on the mechanisms underlying the "inside-out" signaling of S1P, its export through the plasma membrane, and its interaction with cell surface receptors. Membrane lipids, including S1P, do not spontaneously exchange through lipid bilayers since the polar head groups do not readily go through the hydrophobic interior of the plasma membrane. Instead, specific transporter proteins exist on the membrane to exchange these lipids. This review summarizes what is known regarding S1P transport through the cell membrane via ATP-binding cassette transporters and the spinster 2 transporter and discusses the roles for these transporters in cancer and in the tumor microenvironment. Based on our research and the emerging understanding of the role of S1P signaling in cancer and in the tumor microenvironment, S1P transporters and S1P signaling hold promise as new therapeutic targets for cancer drug development. PMID:25133174

  5. Dual Effect of Phosphate Transport on Mitochondrial Ca2+ Dynamics*

    PubMed Central

    Wei, An-Chi; Liu, Ting; O'Rourke, Brian

    2015-01-01

    The large inner membrane electrochemical driving force and restricted volume of the matrix confer unique constraints on mitochondrial ion transport. Cation uptake along with anion and water movement induces swelling if not compensated by other processes. For mitochondrial Ca2+ uptake, these include activation of countertransporters (Na+/Ca2+ exchanger and Na+/H+ exchanger) coupled to the proton gradient, ultimately maintained by the proton pumps of the respiratory chain, and Ca2+ binding to matrix buffers. Inorganic phosphate (Pi) is known to affect both the Ca2+ uptake rate and the buffering reaction, but the role of anion transport in determining mitochondrial Ca2+ dynamics is poorly understood. Here we simultaneously monitor extra- and intra-mitochondrial Ca2+ and mitochondrial membrane potential (ΔΨm) to examine the effects of anion transport on mitochondrial Ca2+ flux and buffering in Pi-depleted guinea pig cardiac mitochondria. Mitochondrial Ca2+ uptake proceeded slowly in the absence of Pi but matrix free Ca2+ ([Ca2+]mito) still rose to ∼50 μm. Pi (0.001–1 mm) accelerated Ca2+ uptake but decreased [Ca2+]mito by almost 50% while restoring ΔΨm. Pi-dependent effects on Ca2+ were blocked by inhibiting the phosphate carrier. Mitochondrial Ca2+ uptake rate was also increased by vanadate (Vi), acetate, ATP, or a non-hydrolyzable ATP analog (AMP-PNP), with differential effects on matrix Ca2+ buffering and ΔΨm recovery. Interestingly, ATP or AMP-PNP prevented the effects of Pi on Ca2+ uptake. The results show that anion transport imposes an upper limit on mitochondrial Ca2+ uptake and modifies the [Ca2+]mito response in a complex manner. PMID:25963147

  6. 21 CFR 862.1720 - Triose phosphate isomerase test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... isomerase test system is a device intended to measure the activity of the enzyme triose phosphate isomerase in erythrocytes (red blood cells). Triose phosphate isomerase is an enzyme important in glycolysis... this device are used in the diagnosis and treatment of congenital triose phosphate isomerase...

  7. 21 CFR 862.1720 - Triose phosphate isomerase test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... isomerase test system is a device intended to measure the activity of the enzyme triose phosphate isomerase in erythrocytes (red blood cells). Triose phosphate isomerase is an enzyme important in glycolysis... this device are used in the diagnosis and treatment of congenital triose phosphate isomerase...

  8. 21 CFR 862.1720 - Triose phosphate isomerase test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... isomerase test system is a device intended to measure the activity of the enzyme triose phosphate isomerase in erythrocytes (red blood cells). Triose phosphate isomerase is an enzyme important in glycolysis... this device are used in the diagnosis and treatment of congenital triose phosphate isomerase...

  9. 21 CFR 862.1720 - Triose phosphate isomerase test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... isomerase test system is a device intended to measure the activity of the enzyme triose phosphate isomerase in erythrocytes (red blood cells). Triose phosphate isomerase is an enzyme important in glycolysis... this device are used in the diagnosis and treatment of congenital triose phosphate isomerase...

  10. 21 CFR 862.1720 - Triose phosphate isomerase test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... isomerase test system is a device intended to measure the activity of the enzyme triose phosphate isomerase in erythrocytes (red blood cells). Triose phosphate isomerase is an enzyme important in glycolysis... this device are used in the diagnosis and treatment of congenital triose phosphate isomerase...

  11. Modeling of glycerol-3-phosphate transporter suggests a potential 'tilt' mechanism involved in its function.

    PubMed

    Tsigelny, Igor F; Greenberg, Jerry; Kouznetsova, Valentina; Nigam, Sanjay K

    2008-10-01

    Many major facilitator superfamily (MFS) transporters have similar 12-transmembrane alpha-helical topologies with two six-helix halves connected by a long loop. In humans, these transporters participate in key physiological processes and are also, as in the case of members of the organic anion transporter (OAT) family, of pharmaceutical interest. Recently, crystal structures of two bacterial representatives of the MFS family--the glycerol-3-phosphate transporter (GlpT) and lac-permease (LacY)--have been solved and, because of assumptions regarding the high structural conservation of this family, there is hope that the results can be applied to mammalian transporters as well. Based on crystallography, it has been suggested that a major conformational "switching" mechanism accounts for ligand transport by MFS proteins. This conformational switch would then allow periodic changes in the overall transporter configuration, resulting in its cyclic opening to the periplasm or cytoplasm. Following this lead, we have modeled a possible "switch" mechanism in GlpT, using the concept of rotation of protein domains as in the DynDom program17 and membranephilic constraints predicted by the MAPAS program.(23) We found that the minima of energies of intersubunit interactions support two alternate positions consistent with their transport properties. Thus, for GlpT, a "tilt" of 9 degrees -10 degrees rotation had the most favorable energetics of electrostatic interaction between the two halves of the transporter; moreover, this confirmation was sufficient to suggest transport of the ligand across the membrane. We conducted steered molecular dynamics simulations of the GlpT-ligand system to explore how glycerol-3-phosphate would be handled by the "tilted" structure, and obtained results generally consistent with experimental mutagenesis data. While biochemical data remain most consistent with a single-site alternating access model, our results raise the possibility that, while the

  12. [Removal of Phosphate by Calcite in Open-System].

    PubMed

    Li, Zhen-xuan; Diao, Jia-yong; Huang, Li-dong; Chen, Yan-fan; Liu, Da-gang; Xu, Zheng-wen

    2015-12-01

    Batch methods were deployed to study the removal of phosphate by calcite in an open-system. Results showed that: (1) The pre-equilibrium process of calcite in open system could be achieved within 24 hours (2) The kinetic results showed that, at initial concentration of 0.5 mg · L⁻¹, the phosphate removal was almost completed within 10 hours of the first phase. The observation may be attributed to surface adsorption. At initial concentration of 2.5 mg · L⁻¹, the phosphate removal was mainly carried out by the precipitation of phosphate at later stage of the process; (3) At initial concentration of ≤ 2.5 mg · L⁻¹ setting 10 h as reaction time, the phosphate removal process was described well by the Langmuir model. It is hypothesized that surface adsorption was the principal removal way of phosphate; (4) With the addition of phthalate, at initial concentration of < 2.5 mg · L⁻¹, the phosphate removal rate experienced a small decrease. That was because phosphate was mainly removed by surface adsorption, and thus, phthalate was a competitor to phosphate for the same adsorption site. The phosphate removal rate increased a little at initial concentration of > 2.5 mg · L⁻¹, this was because the phosphate precipitation was reinforced by the increase of calcium concentration, which was caused by phthalate addition. PMID:27011989

  13. The inhibition of mitochondrial dicarboxylate transport by inorganic phosphate, some phosphate esters and some phosphonate compounds.

    PubMed

    Johnson, R N; Chappell, J B

    1974-02-01

    1. P(i) competitively inhibited succinate oxidation by intact uncoupled mitochondria in the presence of sufficient N-ethylmaleimide to block the phosphate carrier, with a K(i) of 2.5mm. 2. Of a large number of phosphate esters and phosphonate compounds, phenyl phosphate and phenylphosphonate were found to inhibit competitively uncoupled succinate oxidation by intact but not broken mitochondria. By comparison, benzoate was a relatively weak competitive inhibitor of succinate oxidation by intact mitochondria but a relatively potent inhibitor of succinate dehydrogenase. 3. Phenyl phosphate and phenylphosphonate were non-penetrant, and inhibited P(i)-dependent swelling of mitochondria suspended in isosmolar ammonium malate in a manner non-competitive with P(i). The inhibitors did not affect mitochondrial swelling when tested with P(i) alone. 4. It is concluded that: (i) phenyl phosphate and phenylphosphonate behaved as non-penetrant analogues of P(i), since their inhibitory properties were in strict contrast with those of benzoate; (ii) phenyl phosphate and phenylphosphonate interacted with the dicarboxylate carrier but not with the phosphate carrier; (iii) P(i) was effective as a competitive inhibitor of succinate oxidation because of its being either an alternative substrate for the dicarboxylate carrier or competitive with succinate for the intramitochondrial cations as proposed by Harris & Manger (1968). PMID:4822730

  14. Simulation of phosphate transport in sewage-contaminated groundwater, Cape Cod, Massachusetts

    USGS Publications Warehouse

    Stollenwerk, K.G.

    1996-01-01

    Sewage-contaminated groundwater currently discharges to Ashumet Pond, located on Cape Cod, Massachusetts Phosphate concentrations as high as 60 ??mol l-1 have been measured in groundwater entering Ashumet Pond, and there is concern that the rate of eutrophication could increase. Phosphate in the sewage plume is sorbed by aquifer sediment; the amount is a function of phosphate concentration and pH. A nonelectrostatic surface-complexation model coupled with a one-dimensional solute-transport code was used to simulate sorption and desorption of phosphate in laboratory column experiments. The model simulated sorption of phosphate reasonably well, although the slow rate of approach to complete breakthrough indicated a nonequilibrium process that was not accounted for in the solute-transport model The rate of phosphate desorption in the column experiments was relatively slow Phosphate could still be measured in effluent after 160 pore volumes of uncontaminated groundwater had been flushed through the columns. Desorption was partly a function of the slowly decreasing pH in the columns and could be modeled quantitatively. Disposal of sewage at this site is scheduled to stop in 1995; however, a large reservoir of sorbed phosphate exists on aquifer sediment upgradient from Ashumet Pond. Computer simulations predict that desorption of phosphate could result in contamination of Ashumet Pond for decades.

  15. Molecular mechanism of {alpha}-tocopheryl-phosphate transport across the cell membrane

    SciTech Connect

    Negis, Yesim; Meydani, Mohsen; Zingg, Jean-Marc; Azzi, Angelo . E-mail: angelo.azzi@tufts.edu

    2007-07-27

    {alpha}-Tocopheryl-phosphate ({alpha}-TP) is synthesized and hydrolyzed in animal cells and tissues where it modulates several functions. {alpha}-TP is more potent than {alpha}-T in inhibiting cell proliferation, down-regulating CD36 transcription, inhibiting atherosclerotic plaque formation. Administration of {alpha}-TP to cells or animals requires its transfer through membranes, via a transporter. We show here that {alpha}-TP is passing the plasma membrane via a system that is inhibited by glibenclamide and probenecid, inhibitors of a number of transporters. Glibenclamide and probenecid prevent dose-dependently {alpha}-TP inhibition of cell proliferation. The two inhibitors act on ATP binding cassette (ABC) and organic anion transporters (OAT). Since ABC transporters function to export solutes and {alpha}-TP is transported into cells, it may be concluded that {alpha}-TP transport may occur via an OAT family member. Due to the protection by glibenclamide and probenecid on the {alpha}-TP induced cell growth inhibition it appears that {alpha}-TP acts after its uptake inside cells.

  16. Charge Localization and Transport in Lithiated Olivine Phosphate Materials

    SciTech Connect

    Yu, Jianguo; Rosso, Kevin M.; Liu, Jun

    2011-11-10

    We report density functional theory (DFT) calculations for olivine-type LiTMPO4 and TMPO4 (TM=Mn, Fe, Co, Ni) structures, using GGA+U and the B3LYP hybrid density functional that includes nonlocal Fock exchange. TM is typically characterized in terms of the formal oxide states of 2+ or 3+, corresponding to TM with localized charge in LiTMPO4 and TMPO4 structures, respectively, in which electron transport would take place by thermally activated hopping of electrons strongly localized on the transition metal (small polarons). In this work, we assess the validity of the concept of formal TM oxidation states in these materials, and conclude that the valence depends in large part on the strength of d-p hybridization. Stable small polaron formation, i.e., mixed 2+ and 3+ valence states, appears to require that the ratio of differences in the metal and oxygen ionic charges (dQTM/dQO) of the two end member phases is larger than 2, corresponding to the mixed-valence TM system. If the ratio of dQTM/dQO is smaller than 2, excess electrons prefer delocalization and the system behaves more single-valence like with charge transport more akin to metallic conduction. The critical ratio emerging from our analysis may turn out to be relevant to other transition metal systems as well, as a criterion to discriminate single-valence or mixed-valence characteristics and hence the predominant conduction mechanism.

  17. Phosphorus: Riverine system transport

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The transport and transformation of phosphorus (P) in riverine systems fundamentally affects the outcome of watershed mitigation strategies aimed at curbing downstream eutrophication. Phosphorus transport and transformations in streams and rivers are mediated by physical (sediment deposition and res...

  18. Identification of protein components of the microsomal glucose 6-phosphate transporter by photoaffinity labelling.

    PubMed Central

    Kramer, W; Burger, H J; Arion, W J; Corsiero, D; Girbig, F; Weyland, C; Hemmerle, H; Petry, S; Habermann, P; Herling, A

    1999-01-01

    The glucose-6-phosphatase system catalyses the terminal step of hepatic glucose production from both gluconeogenesis and glycogenolysis and is thus a key regulatory factor of blood glucose homoeostasis. To identify the glucose 6-phosphate transporter T1, we have performed photoaffinity labelling of human and rat liver microsomes by using the specific photoreactive glucose-6-phosphate translocase inhibitors S 0957 and S 1743. Membrane proteins of molecular mass 70, 55, 33 and 31 kDa were labelled in human microsomes by [3H]S 0957, whereas in rat liver microsomes bands at 95, 70, 57, 54, 50, 41, 33 and 31 kDa were detectable. The photoprobe [3H]S 1743 led to the predominant labelling of a 57 kDa and a 50 kDa protein in the rat. Stripping of microsomes with 0.3% CHAPS retains the specific binding of T1 inhibitors; photoaffinity labelling of such CHAPS-treated microsomes resulted in the labelling of membrane proteins of molecular mass 55, 33 and 31 kDa in human liver and 50, 33 and 31 kDa in rat liver. Photoaffinity labelling of human liver tissue samples from a healthy individual and from liver samples of patients with a diagnosed glycogen-storage disease type 1b (GSD type 1b; von Gierke's disease) revealed the absence of the 55 kDa protein from one of the patients with GSD type 1. These findings support the identity of the glucose 6-phosphate transporter T1, with endoplasmic reticulum protein of molecular mass 50 kDa in rat liver and 55 kDa in human liver. PMID:10215602

  19. Identification of protein components of the microsomal glucose 6-phosphate transporter by photoaffinity labelling.

    PubMed

    Kramer, W; Burger, H J; Arion, W J; Corsiero, D; Girbig, F; Weyland, C; Hemmerle, H; Petry, S; Habermann, P; Herling, A

    1999-05-01

    The glucose-6-phosphatase system catalyses the terminal step of hepatic glucose production from both gluconeogenesis and glycogenolysis and is thus a key regulatory factor of blood glucose homoeostasis. To identify the glucose 6-phosphate transporter T1, we have performed photoaffinity labelling of human and rat liver microsomes by using the specific photoreactive glucose-6-phosphate translocase inhibitors S 0957 and S 1743. Membrane proteins of molecular mass 70, 55, 33 and 31 kDa were labelled in human microsomes by [3H]S 0957, whereas in rat liver microsomes bands at 95, 70, 57, 54, 50, 41, 33 and 31 kDa were detectable. The photoprobe [3H]S 1743 led to the predominant labelling of a 57 kDa and a 50 kDa protein in the rat. Stripping of microsomes with 0.3% CHAPS retains the specific binding of T1 inhibitors; photoaffinity labelling of such CHAPS-treated microsomes resulted in the labelling of membrane proteins of molecular mass 55, 33 and 31 kDa in human liver and 50, 33 and 31 kDa in rat liver. Photoaffinity labelling of human liver tissue samples from a healthy individual and from liver samples of patients with a diagnosed glycogen-storage disease type 1b (GSD type 1b; von Gierke's disease) revealed the absence of the 55 kDa protein from one of the patients with GSD type 1. These findings support the identity of the glucose 6-phosphate transporter T1, with endoplasmic reticulum protein of molecular mass 50 kDa in rat liver and 55 kDa in human liver. PMID:10215602

  20. ESCRT-III-Associated Protein ALIX Mediates High-Affinity Phosphate Transporter Trafficking to Maintain Phosphate Homeostasis in Arabidopsis

    PubMed Central

    Cardona-López, Ximena; Cuyas, Laura; Marín, Elena; Irigoyen, María Luisa; Gil, Erica; Puga, María Isabel; Bligny, Richard; Nussaume, Laurent; Geldner, Niko; Paz-Ares, Javier

    2015-01-01

    Prior to the release of their cargoes into the vacuolar lumen, sorting endosomes mature into multivesicular bodies (MVBs) through the action of ENDOSOMAL COMPLEX REQUIRED FOR TRANSPORT (ESCRT) protein complexes. MVB-mediated sorting of high-affinity phosphate transporters (PHT1) to the vacuole limits their plasma membrane levels under phosphate-sufficient conditions, a process that allows plants to maintain phosphate homeostasis. Here, we describe ALIX, a cytosolic protein that associates with MVB by interacting with ESCRT-III subunit SNF7 and mediates PHT1;1 trafficking to the vacuole in Arabidopsis thaliana. We show that the partial loss-of-function mutant alix-1 displays reduced vacuolar degradation of PHT1;1. ALIX derivatives containing the alix-1 mutation showed reduced interaction with SNF7, providing a simple molecular explanation for impaired cargo trafficking in alix-1 mutants. In fact, the alix-1 mutation also hampered vacuolar sorting of the brassinosteroid receptor BRI1. We also show that alix-1 displays altered vacuole morphogenesis, implying a new role for ALIX proteins in vacuolar biogenesis, likely acting as part of ESCRT-III complexes. In line with a presumed broad target spectrum, the alix-1 mutation is pleiotropic, leading to reduced plant growth and late flowering, with stronger alix mutations being lethal, indicating that ALIX participates in diverse processes in plants essential for their life. PMID:26342016

  1. The Rice CK2 Kinase Regulates Trafficking of Phosphate Transporters in Response to Phosphate Levels[OPEN

    PubMed Central

    Chen, Jieyu; Wang, Yifeng; Wang, Fei; Yang, Jian; Gao, Mingxing; Li, Changying; Liu, Yingyao; Liu, Yu; Yamaji, Naoki; Ma, Jian Feng; Paz-Ares, Javier; Nussaume, Laurent; Zhang, Shuqun; Yi, Keke; Wu, Zhongchang; Wu, Ping

    2015-01-01

    Phosphate transporters (PTs) mediate phosphorus uptake and are regulated at the transcriptional and posttranslational levels. In one key mechanism of posttranslational regulation, phosphorylation of PTs affects their trafficking from the endoplasmic reticulum (ER) to the plasma membrane. However, the kinase(s) mediating PT phosphorylation and the mechanism leading to ER retention of phosphorylated PTs remain unclear. In this study, we identified a rice (Oryza sativa) kinase subunit, CK2β3, which interacts with PT2 and PT8 in a yeast two-hybrid screen. Also, the CK2α3/β3 holoenzyme phosphorylates PT8 under phosphate-sufficient conditions. This phosphorylation inhibited the interaction of PT8 with PHOSPHATE TRANSPORTER TRAFFIC FACILITATOR1, a key cofactor regulating the exit of PTs from the ER to the plasma membrane. Additionally, phosphorus starvation promoted CK2β3 degradation, relieving the negative regulation of PT phosphorus-insufficient conditions. In accordance, transgenic expression of a nonphosphorylatable version of OsPT8 resulted in elevated levels of that protein at the plasma membrane and enhanced phosphorus accumulation and plant growth under various phosphorus regimes. Taken together, these results indicate that CK2α3/β3 negatively regulates PTs and phosphorus status regulates CK2α3/β3. PMID:25724641

  2. A Constitutive Expressed Phosphate Transporter, OsPht1;1, Modulates Phosphate Uptake and Translocation in Phosphate-Replete Rice1[W][OA

    PubMed Central

    Sun, Shubin; Gu, Mian; Cao, Yue; Huang, Xinpeng; Zhang, Xiao; Ai, Penghui; Zhao, Jianning; Fan, Xiaorong; Xu, Guohua

    2012-01-01

    A number of phosphate (Pi) starvation- or mycorrhiza-regulated Pi transporters belonging to the Pht1 family have been functionally characterized in several plant species, whereas functions of the Pi transporters that are not regulated by changes in Pi supply are lacking. In this study, we show that rice (Oryza sativa) Pht1;1 (OsPT1), one of the 13 Pht1 Pi transporters in rice, was expressed abundantly and constitutively in various cell types of both roots and shoots. OsPT1 was able to complement the proton-coupled Pi transporter activities in a yeast mutant defective in Pi uptake. Transgenic plants of OsPT1 overexpression lines and RNA interference knockdown lines contained significantly higher and lower phosphorus concentrations, respectively, compared with the wild-type control in Pi-sufficient shoots. These responses of the transgenic plants to Pi supply were further confirmed by the changes in depolarization of root cell membrane potential, root hair occurrence, 33P uptake rate and transportation, as well as phosphorus accumulation in young leaves at Pi-sufficient levels. Furthermore, OsPT1 expression was strongly enhanced by the mutation of Phosphate Overaccumulator2 (OsPHO2) but not by Phosphate Starvation Response2, indicating that OsPT1 is involved in the OsPHO2-regulated Pi pathway. These results indicate that OsPT1 is a key member of the Pht1 family involved in Pi uptake and translocation in rice under Pi-replete conditions. PMID:22649273

  3. Transportation System Requirements Document

    SciTech Connect

    Not Available

    1993-09-01

    This Transportation System Requirements Document (Trans-SRD) describes the functions to be performed by and the technical requirements for the Transportation System to transport spent nuclear fuel (SNF) and high-level radioactive waste (HLW) from Purchaser and Producer sites to a Civilian Radioactive Waste Management System (CRWMS) site, and between CRWMS sites. The purpose of this document is to define the system-level requirements for Transportation consistent with the CRWMS Requirement Document (CRD). These requirements include design and operations requirements to the extent they impact on the development of the physical segments of Transportation. The document also presents an overall description of Transportation, its functions, its segments, and the requirements allocated to the segments and the system-level interfaces with Transportation. The interface identification and description are published in the CRWMS Interface Specification.

  4. Phosphate depletion modulates auxin transport in Triticum aestivum leading to altered root branching

    PubMed Central

    Talboys, Peter J.; Healey, John R.; Withers, Paul J. A.; Jones, Davey L.

    2014-01-01

    Understanding the mechanisms by which nutritional signals impact upon root system architecture is a key facet in the drive for greater nutrient application efficiency in agricultural systems. Cereal plants reduce their rate of lateral root emergence under inorganic phosphate (Pi) shortage; this study uses molecular and pharmacological techniques to dissect this Pi response in Triticum aestivum. Plants were grown in coarse sand washed in high- or low-Pi nutrient solution before being assessed for their root branching density and expression of AUX/IAA and PIN genes. Seedlings were also grown on media containing [14C]indole acetic acid to measure basipetal auxin transport. Seedlings grown in low-Pi environments displayed less capacity to transport auxin basipetally from the seminal root apex, a reduction in root expression of PIN auxin transporter genes, and perturbed expression of a range of AUX/IAA auxin response genes. Given the known importance of basipetally transported auxin in stimulating lateral root initiation, it is proposed here that, in T. aestivum, Pi availability directly influences lateral root production through modulation of PIN expression. Understanding such processes is important in the drive for greater efficiency in crop use of Pi fertilizers in agricultural settings. PMID:25086590

  5. Phosphate depletion modulates auxin transport in Triticum aestivum leading to altered root branching.

    PubMed

    Talboys, Peter J; Healey, John R; Withers, Paul J A; Jones, Davey L

    2014-09-01

    Understanding the mechanisms by which nutritional signals impact upon root system architecture is a key facet in the drive for greater nutrient application efficiency in agricultural systems. Cereal plants reduce their rate of lateral root emergence under inorganic phosphate (Pi) shortage; this study uses molecular and pharmacological techniques to dissect this Pi response in Triticum aestivum. Plants were grown in coarse sand washed in high- or low-Pi nutrient solution before being assessed for their root branching density and expression of AUX/IAA and PIN genes. Seedlings were also grown on media containing [(14)C]indole acetic acid to measure basipetal auxin transport. Seedlings grown in low-Pi environments displayed less capacity to transport auxin basipetally from the seminal root apex, a reduction in root expression of PIN auxin transporter genes, and perturbed expression of a range of AUX/IAA auxin response genes. Given the known importance of basipetally transported auxin in stimulating lateral root initiation, it is proposed here that, in T. aestivum, Pi availability directly influences lateral root production through modulation of PIN expression. Understanding such processes is important in the drive for greater efficiency in crop use of Pi fertilizers in agricultural settings. PMID:25086590

  6. Deregulated Renal Calcium and Phosphate Transport during Experimental Kidney Failure

    PubMed Central

    van Loon, Ellen P.; van de Sluis, Bart; Vervloet, Mark G.; Hoenderop, Joost G.; Bindels, René J.

    2015-01-01

    Impaired mineral homeostasis and inflammation are hallmarks of chronic kidney disease (CKD), yet the underlying mechanisms of electrolyte regulation during CKD are still unclear. Here, we applied two different murine models, partial nephrectomy and adenine-enriched dietary intervention, to induce kidney failure and to investigate the subsequent impact on systemic and local renal factors involved in Ca2+ and Pi regulation. Our results demonstrated that both experimental models induce features of CKD, as reflected by uremia, and elevated renal neutrophil gelatinase-associated lipocalin (NGAL) expression. In our model kidney failure was associated with polyuria, hypercalcemia and elevated urinary Ca2+ excretion. In accordance, CKD augmented systemic PTH and affected the FGF23-αklotho-vitamin-D axis by elevating circulatory FGF23 levels and reducing renal αklotho expression. Interestingly, renal FGF23 expression was also induced by inflammatory stimuli directly. Renal expression of Cyp27b1, but not Cyp24a1, and blood levels of 1,25-dihydroxy vitamin D3 were significantly elevated in both models. Furthermore, kidney failure was characterized by enhanced renal expression of the transient receptor potential cation channel subfamily V member 5 (TRPV5), calbindin-D28k, and sodium-dependent Pi transporter type 2b (NaPi2b), whereas the renal expression of sodium-dependent Pi transporter type 2a (NaPi2a) and type 3 (PIT2) were reduced. Together, our data indicates two different models of experimental kidney failure comparably associate with disturbed FGF23-αklotho-vitamin-D signalling and a deregulated electrolyte homeostasis. Moreover, this study identifies local tubular, possibly inflammation- or PTH- and/or FGF23-associated, adaptive mechanisms, impacting on Ca2+/Pi homeostasis, hence enabling new opportunities to target electrolyte disturbances that emerge as a consequence of CKD development. PMID:26566277

  7. Role of the sodium-dependent phosphate co-transporters and of the phosphate complexes of uranyl in the cytotoxicity of uranium in LLC-PK{sub 1} cells

    SciTech Connect

    Muller, D. . E-mail: dany.muller@kcl.ac.uk; Houpert, P. . E-mail: pascale.houpert@irsn.fr; Cambar, J. . E-mail: marie-helene.napoli@cea.fr

    2006-07-15

    Although uranium is a well-characterized nephrotoxic agent, very little is known at the cellular and molecular level about the mechanisms underlying the uptake and toxicity of this element in proximal tubule cells. The aim of this study was thus to characterize the species of uranium that are responsible for its cytotoxicity and define the mechanism which is involved in the uptake of the cytotoxic fraction of uranium using two cell lines derived from kidney proximal (LLC-PK{sub 1}) and distal (MDCK) tubule as in vitro models. Treatment of LLC-PK{sub 1} cells with colchicine, cytochalasin D, concanavalin A and PMA increased the sodium-dependent phosphate co-transport and the cytotoxicity of uranium. On the contrary, replacement of the extra-cellular sodium with N-methyl-D-glucamine highly reduced the transport of phosphate and the cytotoxic effect of uranium. Uranium cytotoxicity was also dependent upon the extra-cellular concentration of phosphate and decreased in a concentration-dependent manner by 0.1-10 mM phosphonoformic acid, a competitive inhibitor of phosphate uptake. Consistent with these observations, over-expression of the rat proximal tubule sodium-dependent phosphate co-transporter NaPi-IIa in stably transfected MDCK cells significantly increased the cytotoxicity of uranium, and computer modeling of uranium speciation showed that uranium cytotoxicity was directly dependent on the presence of the phosphate complexes of uranyl UO{sub 2}(PO{sub 4}){sup -} and UO{sub 2}(HPO{sub 4}){sub aq}. Taken together, these data suggest that the cytotoxic fraction of uranium is a phosphate complex of uranyl whose uptake is mediated by a sodium-dependent phosphate co-transporter system.

  8. Mycobacterium tuberculosis Phosphate Uptake System Component PstA2 Is Not Required for Gene Regulation or Virulence

    PubMed Central

    Leistikow, Rachel L.; Ramakrishnan, Pavithra; Voskuil, Martin I.; McKinney, John D.

    2016-01-01

    The Mycobacterium tuberculosis genome encodes two complete high-affinity Pst phosphate-specific transporters. We previously demonstrated that a membrane-spanning component of one Pst system, PstA1, was essential both for M. tuberculosis virulence and for regulation of gene expression in response to external phosphate availability. To determine if the alternative Pst system is similarly required for virulence or gene regulation, we constructed a deletion of pstA2. Transcriptome analysis revealed that PstA2 is not required for regulation of gene expression in phosphate-replete growth conditions. PstA2 was also dispensable for replication and virulence of M. tuberculosis in a mouse aerosol infection model. However, a ΔpstA1ΔpstA2 double mutant was attenuated in mice lacking the cytokine interferon-gamma, suggesting that M. tuberculosis requires high-affinity phosphate transport to survive phosphate limitation encountered in the host. Surprisingly, ΔpstA2 bacteria were more resistant to acid stress in vitro. This phenotype is intrinsic to the alternative Pst transporter since a ΔpstS1 mutant exhibited similar acid resistance. Our data indicate that the two M. tuberculosis Pst transporters have distinct physiological functions, with the PstA1 transporter being specifically involved in phosphate sensing and gene regulation while the PstA2 transporter influences survival in acidic conditions. PMID:27557082

  9. Mycobacterium tuberculosis Phosphate Uptake System Component PstA2 Is Not Required for Gene Regulation or Virulence.

    PubMed

    Tischler, Anna D; Leistikow, Rachel L; Ramakrishnan, Pavithra; Voskuil, Martin I; McKinney, John D

    2016-01-01

    The Mycobacterium tuberculosis genome encodes two complete high-affinity Pst phosphate-specific transporters. We previously demonstrated that a membrane-spanning component of one Pst system, PstA1, was essential both for M. tuberculosis virulence and for regulation of gene expression in response to external phosphate availability. To determine if the alternative Pst system is similarly required for virulence or gene regulation, we constructed a deletion of pstA2. Transcriptome analysis revealed that PstA2 is not required for regulation of gene expression in phosphate-replete growth conditions. PstA2 was also dispensable for replication and virulence of M. tuberculosis in a mouse aerosol infection model. However, a ΔpstA1ΔpstA2 double mutant was attenuated in mice lacking the cytokine interferon-gamma, suggesting that M. tuberculosis requires high-affinity phosphate transport to survive phosphate limitation encountered in the host. Surprisingly, ΔpstA2 bacteria were more resistant to acid stress in vitro. This phenotype is intrinsic to the alternative Pst transporter since a ΔpstS1 mutant exhibited similar acid resistance. Our data indicate that the two M. tuberculosis Pst transporters have distinct physiological functions, with the PstA1 transporter being specifically involved in phosphate sensing and gene regulation while the PstA2 transporter influences survival in acidic conditions. PMID:27557082

  10. Investigation of ionic transport in sodium scandium phosphate (NSP) and related compounds

    NASA Astrophysics Data System (ADS)

    Bhat, Kaustubh; Blügel, Stefan; Lustfeld, Hans

    Sodium ionic conductors offer significant advantages for application in large scale energy storage systems. In this study, we investigate the different pathways available for sodium ion conduction in NSP and calculate energy barriers for ionic transport using Density Functional Theory (DFT) and the Nudged Elastic Band Method. We identify the structural parameters that reduce the energy barrier, by calculating the influence of positive and negative external pressure on the energy barrier. Lattice strain can be introduced by cation or anion substitution within the NASICON structure. We substitute the scandium atom with other trivalent atoms such as aluminium and yttrium, and calculate the resulting energy barriers. Sodium thiophosphate (Na3PS4) has previously shown about two orders of magnitude higher ionic conductivity than sodium phosphate (Na3PO4). We investigate the effect of substituting oxygen with sulphur in NSP. We acknowledge discussions with our experimental colleagues F. Tietz and M. Guin toward this work

  11. Payload transportation system study

    NASA Technical Reports Server (NTRS)

    1976-01-01

    A standard size set of shuttle payload transportation equipment was defined that will substantially reduce the cost of payload transportation and accommodate a wide range of payloads with minimum impact on payload design. The system was designed to accommodate payload shipments between the level 4 payload integration sites and the launch site during the calendar years 1979-1982. In addition to defining transportation multi-use mission support equipment (T-MMSE) the mode of travel, prime movers, and ancillary equipment required in the transportation process were also considered. Consistent with the STS goals of low cost and the use of standardized interfaces, the transportation system was designed to commercial grade standards and uses the payload flight mounting interfaces for transportation. The technical, cost, and programmatic data required to permit selection of a baseline system of MMSE for intersite movement of shuttle payloads were developed.

  12. Glucose-6-phosphate transport activity in liver microsomes exposed to stilbene disulfonate derivatives

    SciTech Connect

    Countaway, J.L.; Arion, W.J.

    1986-05-01

    Glucose-6-P (G6P) hydrolysis by hepatic microsomes (MS) is mediated by a coupled system composed of the G6P transporter (T1), the enzyme (E) and a phosphate transporter (T2). Zoccoli et al. concluded that T1 is a 54 kDa protein based on a linear correlation of labeling by /sup 3/H-4,4'diisothiocyano-1,2-diphenylethane-2,2'-disulfonate (/sup 3/H-H/sub 2/DIDS) and inhibition of system activity. The authors cannot support this conclusion: (1) in their hands the reaction of /sup 3/H-H/sub 2/DIDS with MS proteins is extremely nonspecific, and (2) the linear correlation must be between labeling and inhibition of T1 activity, because transport per se is not the absolute rate limiting step in hydrolysis by the system. Point 2 is readily demonstrated by examining the influence of the enzyme inhibitor, D-glucose, on the sensitivity of the system to inhibition by H/sub 2/DIDS. Studies of H/sub 2/DIDS inhibition of the system in MS from fasted and diabetic rats revealed that the observed inhibition constant for the system, K/sub i(S)/, is inversely proportional to the fraction of latent G6Pase activity (LF) seen before exposure to H/sub 2/DIDS, and K/sub i(S)/ x LF - K/sub i(T1)/, the inhibition constant for T1 activity. This relationship is derived from the equation 1/V/sub (S)/ - 1/V/sub (E)/ = 1/V/sub (T1)/, where V denotes the initial rates of S, E and T1, respectively. The latter equation can be used to calculate V/sub (T1)/ for any preparation of intact MS, and it predicts that labeling and inhibition of T1 will be linearly correlated with V/sub (T1)/ but not V/sub (S)/.

  13. Analysis of the Plastidic phosphate translocator Gene Family in Arabidopsis and Identification of New phosphate translocator-Homologous Transporters, Classified by Their Putative Substrate-Binding Site1

    PubMed Central

    Knappe, Silke; Flügge, Ulf-Ingo; Fischer, Karsten

    2003-01-01

    Analysis of the Arabidopsis genome revealed the complete set of plastidic phosphate translocator (pPT) genes. The Arabidopsis genome contains 16 pPT genes: single copies of genes coding for the triose phosphate/phosphate translocator and the xylulose phosphate/phosphate translocator, and two genes coding for each the phosphoenolpyruvate/phosphate translocator and the glucose-6-phosphate/phosphate translocator. A relatively high number of truncated phosphoenolpyruvate/phosphate translocator genes (six) and glucose-6-phosphate/phosphate translocator genes (four) could be detected with almost conserved intron/exon structures as compared with the functional genes. In addition, a variety of PT-homologous (PTh) genes could be identified in Arabidopsis and other organisms. They all belong to the drug/metabolite transporter superfamily showing significant similarities to nucleotide sugar transporters (NSTs). The pPT, PTh, and NST proteins all possess six to eight transmembrane helices. According to the analysis of conserved motifs in these proteins, the PTh proteins can be divided into (a) the lysine (Lys)/arginine group comprising only non-plant proteins, (b) the Lys-valine/alanine/glycine group of Arabidopsis proteins, (c) the Lys/asparagine group of Arabidopsis proteins, and (d) the Lys/threonine group of plant and non-plant proteins. None of these proteins have been characterized so far. The analysis of the putative substrate-binding sites of the pPT, PTh, and NST proteins led to the suggestion that all these proteins share common substrate-binding sites on either side of the membrane each of which contain a conserved Lys residue. PMID:12644669

  14. Rice SPX-Major Facility Superfamily3, a Vacuolar Phosphate Efflux Transporter, Is Involved in Maintaining Phosphate Homeostasis in Rice.

    PubMed

    Wang, Chuang; Yue, Wenhao; Ying, Yinghui; Wang, Shoudong; Secco, David; Liu, Yu; Whelan, James; Tyerman, Stephen D; Shou, Huixia

    2015-12-01

    To maintain a stable cytosol phosphate (Pi) concentration, plant cells store Pi in their vacuoles. When the Pi concentration in the cytosol decreases, Pi is exported from the vacuole into the cytosol. This export is mediated by Pi transporters on the tonoplast. In this study, we demonstrate that SYG1, PHO81, and XPR1 (SPX)-Major Facility Superfamily (MFS) proteins have a similar structure with yeast (Saccharomyces cerevisiae) low-affinity Pi transporters Phosphatase87 (PHO87), PHO90, and PHO91. OsSPX-MFS1, OsSPX-MFS2, and OsSPX-MFS3 all localized on the tonoplast of rice (Oryza sativa) protoplasts, even in the absence of the SPX domain. At high external Pi concentration, OsSPX-MFS3 could partially complement the yeast mutant strain EY917 under pH 5.5, which lacks all five Pi transporters present in yeast. In oocytes, OsSPX-MFS3 was shown to facilitate Pi influx or efflux depending on the external pH and Pi concentrations. In contrast to tonoplast localization in plants cells, OsSPX-MFS3 was localized to the plasma membrane when expressed in both yeast and oocytes. Overexpression of OsSPX-MFS3 results in decreased Pi concentration in the vacuole of rice tissues. We conclude that OsSPX-MFS3 is a low-affinity Pi transporter that mediates Pi efflux from the vacuole into cytosol and is coupled to proton movement. PMID:26424157

  15. Space Transportation systems overview

    NASA Technical Reports Server (NTRS)

    Lee, C. M.

    1979-01-01

    Planning for the operations phase of the Space Transportation system is reviewed. Attention is given to mission profile (typical), applications, manifesting rationale, the Operational Flight Test manifest, the operations manifest, pricing policy, and potential applications of the STS.

  16. Smart vehicular transportation systems

    SciTech Connect

    Little, C.Q.; Wilson, C.W.

    1997-05-01

    This work builds upon established Sandia intelligent systems technology to develop a unique approach for the integration of intelligent system control into the US Highway and urban transportation systems. The Sandia developed concept of the COPILOT controller integrates a human driver with computer control to increase human performance while reducing reliance on detailed driver attention. This research extends Sandia expertise in sensor based, real-time control of robotics systems to high speed transportation systems. Knowledge in the form of maps and performance characteristics of vehicles provides the automatic decision making intelligence needed to plan optimum routes, maintain safe driving speeds and distances, avoid collisions, and conserve fuel.

  17. The phosphatonins and the regulation of phosphate transport and vitamin D metabolism.

    PubMed

    Sommer, Stacy; Berndt, Theresa; Craig, Theodore; Kumar, Rajiv

    2007-03-01

    Phosphate homeostasis is preserved during variations in phosphate intake by short-term intrinsic renal and intestinal adaptations in transport processes, and by more long-term hormonal mechanisms, which regulate the efficiency of phosphate transport in the kidney and intestine. Recently, several phosphaturic peptides such as fibroblast growth factor 23 (FGF-23), secreted frizzled-related protein-4 (sFRP-4), extracellular phosphoglycoprotein (MEPE) and fibroblast growth factor 7 (FGF-7) have been shown to play a pathogenic role in several hypophosphatemic disorders such as tumor-induced osteomalacia (TIO), autosomal dominant hypophosphatemic rickets (ADHR), X-linked hypophosphatemic rickets (XLH), the McCune-Albright syndrome (MAS) and fibrous dysplasia (FD). These proteins induce phosphaturia and hypophosphatemia in vivo, and inhibit sodium-dependent renal phosphate transport in cultured renal epithelial cells. Interestingly, despite the induction of hypophosphatemia by FGF-23 and sFRP-4 in vivo, serum 1, 25-dihydroxyvitamin D (1alpha,25(OH)(2)D) concentrations are decreased or remain inappropriately normal, suggesting an inhibitory effect of these proteins on 25-hydroxyvitamin D 1alpha-hydroxylase activity. In FGF-23 knockout mice, 25-hydroxyvitamin D 1alpha-hydroxylase expression is increased and elevated serum 1alpha,25(OH)(2)D levels cause significant hypercalcemia and hyperphosphatemia. MEPE, however, increases circulating 1alpha,25(OH)(2)D. Circulating or local concentrations of these peptides/proteins may regulate 25-hydroxyvitamin D 1alpha-hydroxylase activity in renal tissues under physiologic circumstances. PMID:17224271

  18. Genetic diversity for mycorrhizal symbiosis and phosphate transporters in rice.

    PubMed

    Jeong, Kwanho; Mattes, Nicolas; Catausan, Sheryl; Chin, Joong Hyoun; Paszkowski, Uta; Heuer, Sigrid

    2015-11-01

    Phosphorus (P) is a major plant nutrient and developing crops with higher P-use efficiency is an important breeding goal. In this context we have conducted a comparative study of irrigated and rainfed rice varieties to assess genotypic differences in colonization with arbuscular mycorrhizal (AM) fungi and expression of different P transporter genes. Plants were grown in three different soil samples from a rice farm in the Philippines. The data show that AM symbiosis in all varieties was established after 4 weeks of growth under aerobic conditions and that, in soil derived from a rice paddy, natural AM populations recovered within 6 weeks. The analysis of AM marker genes (AM1, AM3, AM14) and P transporter genes for the direct Pi uptake (PT2, PT6) and AM-mediated pathway (PT11, PT13) were largely in agreement with the observed root AM colonization providing a useful tool for diversity studies. Interestingly, delayed AM colonization was observed in the aus-type rice varieties which might be due to their different root structure and might confer an advantage for weed competition in the field. The data further showed that P-starvation induced root growth and expression of the high-affinity P transporter PT6 was highest in the irrigated variety IR66 which also maintained grain yield under P-deficient field conditions. PMID:26466747

  19. Influence of calcium on phosphate transport in cultured kidney epithelium

    SciTech Connect

    Caverzasio, J.; Bonjour, J.P. )

    1988-02-01

    Renal epithelia cultured from opossum kidney (OK) cell line were exposed to high- and low-Ca media (H{sub Ca}M and L{sub Ca}M, respectively). Changing the extracellular Ca concentration from 2.0 mM to 0.02 mM stimulated sodium-dependent P{sub i} transport (Na{sub P{sub i}}T) of OK epithelia. The effect was detectable after 1 h of L{sub Ca}M exposure and reached a maximal value at 4 h, this difference remaining constant up to 16 h. The Na-dependent transport of both alanine and methyl-{alpha}-D-glucopyranoside, a glucose analogue, were not affect by L{sub Ca}M. Kinetic analysis of Na{sub P{sub i}}T revealed an increase in V{sub max} with no change in the apparent K{sub m}. The cellular adenosine 3{prime},5{prime}-cyclic monophosphate production was not affected by L{sub Ca}M. In OK epithelia pretreated with either cycloheximide or actinomycin D the L{sub Ca}M stimulatory effect was completely abolished. In the presence of 10{sup {minus}9} to 10{sup {minus}7} M bovine parathyroid hormone (1-34), the effect of L{sub Ca}M on Na{sub P{sub i}}T was markedly blunted. In conclusion, this study in cultured kidney epithelia demonstrates that the renal Na{sub P}{sub i}T can be directly and selectively stimulated by lowering the extracellular Ca concentration. This effect required the de novo synthesis of proteins. The results also indicate that parathyroid hormone antagonizes the stimulatory effect of extracellular Ca on the renal transport of P{sub i}.

  20. Crystal Structure of PhnF, a GntR-Family Transcriptional Regulator of Phosphate Transport in Mycobacterium smegmatis

    PubMed Central

    Busby, Jason N.; Fritz, Georg; Moreland, Nicole J.; Cook, Gregory M.; Lott, J. Shaun; Baker, Edward N.

    2014-01-01

    Bacterial uptake of phosphate is usually accomplished via high-affinity transporters that are commonly regulated by two-component systems, which are activated when the concentration of phosphate is low. Mycobacterium smegmatis possesses two such transporters, the widely distributed PstSCAB system and PhnDCE, a transporter that in other bacteria mediates the uptake of alternative phosphorus sources. We previously reported that the transcriptional regulator PhnF controls the production of the Phn system, acting as a repressor under high-phosphate conditions. Here we show that the phnDCE genes are common among environmental mycobacteria, where they are often associated with phnF-like genes. In contrast, pathogenic mycobacteria were not found to encode Phn-like systems but instead were found to possess multiple copies of the pst genes. A detailed biochemical analysis of PhnF binding to its identified binding sites in the phnD-phnF intergenic region of M. smegmatis has allowed us to propose a quantitative model for repressor binding, which shows that a PhnF dimer binds independently to each site. We present the crystal structure of M. smegmatis PhnF at 1.8-Å resolution, showing a homodimer with a helix-turn-helix N-terminal domain and a C-terminal domain with a UbiC transcription regulator-associated fold. The C-terminal domain crystallized with a bound sulfate ion instead of the so far unidentified physiological ligand, allowing the identification of residues involved in effector binding. Comparison of the positioning of the DNA binding domains in PhnF with that in homologous proteins suggests that its DNA binding activity is regulated via a conformational change in the linker region, triggering a movement of the N-terminal domains. PMID:25049090

  1. Arabidopsis thaliana High-Affinity Phosphate Transporters Exhibit Multiple Levels of Posttranslational Regulation[C][W

    PubMed Central

    Bayle, Vincent; Arrighi, Jean-François; Creff, Audrey; Nespoulous, Claude; Vialaret, Jérôme; Rossignol, Michel; Gonzalez, Esperanza; Paz-Ares, Javier; Nussaume, Laurent

    2011-01-01

    In Arabidopsis thaliana, the PHOSPHATE TRANSPORTER1 (PHT1) family encodes the high-affinity phosphate transporters. They are transcriptionally induced by phosphate starvation and require PHOSPHATE TRANSPORTER TRAFFIC FACILITATOR (PHF1) to exit the endoplasmic reticulum (ER), indicating intracellular traffic as an additional level of regulation of PHT1 activity. Our study revealed that PHF1 acts on PHT1, upstream of vesicle coat protein COPII formation, and that additional regulatory events occur during PHT1 trafficking and determine its ER exit and plasma membrane stability. Phosphoproteomic and mutagenesis analyses revealed modulation of PHT1;1 ER export by Ser-514 phosphorylation status. Confocal microscopy analysis of root tip cells showed that PHT1;1 is localized to the plasma membrane and is present in intracellular endocytic compartments. More precisely, PHT1;1 was localized to sorting endosomes associated with prevacuolar compartments. Kinetic analysis of PHT1;1 stability and targeting suggested a modulation of PHT1 internalization from the plasma membrane to the endosomes, followed by either subsequent recycling (in low Pi) or vacuolar degradation (in high Pi). For the latter condition, we identified a rapid mechanism that reduces the pool of PHT1 proteins present at the plasma membrane. This mechanism is regulated by the Pi concentration in the medium and appears to be independent of degradation mechanisms potentially regulated by the PHO2 ubiquitin conjugase. We propose a model for differential trafficking of PHT1 to the plasma membrane or vacuole as a function of phosphate concentration. PMID:21521698

  2. Investigating the Contribution of the Phosphate Transport Pathway to Arsenic Accumulation in Rice1[W

    PubMed Central

    Wu, Zhongchang; Ren, Hongyan; McGrath, Steve P.; Wu, Ping; Zhao, Fang-Jie

    2011-01-01

    Arsenic (As) accumulation in rice (Oryza sativa) may pose a significant health risk to consumers. Plants take up different As species using various pathways. Here, we investigated the contribution of the phosphate (Pi) transport pathway to As accumulation in rice grown hydroponically or under flooded soil conditions. In hydroponic experiments, a rice mutant defective in OsPHF1 (for phosphate transporter traffic facilitator1) lost much of the ability to take up Pi and arsenate and to transport them from roots to shoots, whereas transgenic rice overexpressing either the Pi transporter OsPht1;8 (OsPT8) or the transcription factor OsPHR2 (for phosphate starvation response2) had enhanced abilities of Pi and arsenate uptake and translocation. OsPT8 was found to have a high affinity for both Pi and arsenate, and its overexpression increased the maximum influx by 3- to 5-fold. In arsenate-treated plants, both arsenate and arsenite were detected in the xylem sap, with the proportion of the latter increasing with the exposure time. Under the flooded soil conditions, the phf1 mutant took up less Pi whereas the overexpression lines took up more Pi. But there were no similar effects on As accumulation and distribution. Rice grain contained predominantly dimethylarsinic acid and arsenite, with arsenate being a minor species. These results suggest that the Pi transport pathway contributed little to As uptake and transport to grain in rice plants grown in flooded soil. Transgenic approaches to enhance Pi acquisition from paddy soil through the overexpression of Pi transporters may not increase As accumulation in rice grain. PMID:21715673

  3. Investigating the contribution of the phosphate transport pathway to arsenic accumulation in rice.

    PubMed

    Wu, Zhongchang; Ren, Hongyan; McGrath, Steve P; Wu, Ping; Zhao, Fang-Jie

    2011-09-01

    Arsenic (As) accumulation in rice (Oryza sativa) may pose a significant health risk to consumers. Plants take up different As species using various pathways. Here, we investigated the contribution of the phosphate (Pi) transport pathway to As accumulation in rice grown hydroponically or under flooded soil conditions. In hydroponic experiments, a rice mutant defective in OsPHF1 (for phosphate transporter traffic facilitator1) lost much of the ability to take up Pi and arsenate and to transport them from roots to shoots, whereas transgenic rice overexpressing either the Pi transporter OsPht1;8 (OsPT8) or the transcription factor OsPHR2 (for phosphate starvation response2) had enhanced abilities of Pi and arsenate uptake and translocation. OsPT8 was found to have a high affinity for both Pi and arsenate, and its overexpression increased the maximum influx by 3- to 5-fold. In arsenate-treated plants, both arsenate and arsenite were detected in the xylem sap, with the proportion of the latter increasing with the exposure time. Under the flooded soil conditions, the phf1 mutant took up less Pi whereas the overexpression lines took up more Pi. But there were no similar effects on As accumulation and distribution. Rice grain contained predominantly dimethylarsinic acid and arsenite, with arsenate being a minor species. These results suggest that the Pi transport pathway contributed little to As uptake and transport to grain in rice plants grown in flooded soil. Transgenic approaches to enhance Pi acquisition from paddy soil through the overexpression of Pi transporters may not increase As accumulation in rice grain. PMID:21715673

  4. Transportation Anslysis Simulation System

    SciTech Connect

    2004-08-23

    TRANSIMS version 3.1 is an integrated set of analytical and simulation models and supporting databases. The system is designed to create a virtual metropolitan region with representation of each of the region’s individuals, their activities and the transportation infrastructure they use. TRANSIMS puts into practice a new, disaggregate approach to travel demand modeling using agent-based micro-simulation technology. TRANSIMS methodology creates a virtual metropolitan region with representation of the transportation infrastructure and the population, at the level of households and individual travelers. Trips a planned to satisfy the population’s activity pattems at the individual traveler level. TRANSIMS then simulates the movement of travelers and vehicles across the transportation network using multiple modes, including car, transit, bike and walk, on a second-by-second basis. Metropolitan planners must plan growth of their cities according to the stringent transportation system planning requirements of the Interniodal Surface Transportation Efficiency Act of 1991, the Clean Air Act Amendments of 1990 and other similar laws and regulations. These require each state and its metropotitan regions to work together to develop short and long term transportation improvement plans. The plans must (1) estimate the future transportation needs for travelers and goods movements, (2) evaluate ways to manage and reduce congestion, (3) examine the effectiveness of building new roads and transit systems, and (4) limit the environmental impact of the various strategies. The needed consistent and accurate transportation improvement plans require an analytical capability that properly accounts for travel demand, human behavior, traffic and transit operations, major investments, and environmental effects. Other existing planning tools use aggregated information and representative behavior to predict average response and average use of transportation facilities. They do not account

  5. Transportation Anslysis Simulation System

    Energy Science and Technology Software Center (ESTSC)

    2004-08-23

    TRANSIMS version 3.1 is an integrated set of analytical and simulation models and supporting databases. The system is designed to create a virtual metropolitan region with representation of each of the region’s individuals, their activities and the transportation infrastructure they use. TRANSIMS puts into practice a new, disaggregate approach to travel demand modeling using agent-based micro-simulation technology. TRANSIMS methodology creates a virtual metropolitan region with representation of the transportation infrastructure and the population, at themore » level of households and individual travelers. Trips a planned to satisfy the population’s activity pattems at the individual traveler level. TRANSIMS then simulates the movement of travelers and vehicles across the transportation network using multiple modes, including car, transit, bike and walk, on a second-by-second basis. Metropolitan planners must plan growth of their cities according to the stringent transportation system planning requirements of the Interniodal Surface Transportation Efficiency Act of 1991, the Clean Air Act Amendments of 1990 and other similar laws and regulations. These require each state and its metropotitan regions to work together to develop short and long term transportation improvement plans. The plans must (1) estimate the future transportation needs for travelers and goods movements, (2) evaluate ways to manage and reduce congestion, (3) examine the effectiveness of building new roads and transit systems, and (4) limit the environmental impact of the various strategies. The needed consistent and accurate transportation improvement plans require an analytical capability that properly accounts for travel demand, human behavior, traffic and transit operations, major investments, and environmental effects. Other existing planning tools use aggregated information and representative behavior to predict average response and average use of transportation facilities. They do not

  6. NELL-1 increases pre-osteoblast mineralization using both phosphate transporter Pit1 and Pit2

    SciTech Connect

    Cowan, Catherine M.; Zhang, Xinli; James, Aaron W.; Mari Kim, T.; Sun, Nichole; Wu, Benjamin; Ting, Kang; Soo, Chia

    2012-06-08

    Highlights: Black-Right-Pointing-Pointer NELL-1 accelerates extracellular matrix mineralization in MC3T3-E1 pre-osteoblasts. Black-Right-Pointing-Pointer NELL-1 significantly increases intracellular inorganic phosphate levels. Black-Right-Pointing-Pointer NELL-1 positively regulates osteogenesis but not proliferation in MC3T3-E1 cells. Black-Right-Pointing-Pointer NELL-1 regulates inorganic phosphate transporter activity. -- Abstract: NELL-1 is a potent osteoinductive molecule that enhances bone formation in multiple animal models through currently unidentified pathways. In the present manuscript, we hypothesized that NELL-1 may regulate osteogenic differentiation accompanied by alteration of inorganic phosphate (Pi) entry into the osteoblast via sodium dependent phosphate (NaPi) transporters. To determine this, MC3T3-E1 pre-osteoblasts were cultured in the presence of recombinant human (rh)NELL-1 or rhBMP-2. Analysis was performed for intracellular Pi levels through malachite green staining, Pit-1 and Pit-2 expression, and forced upregulation of Pit-1 and Pit-2. Results showed rhNELL-1 to increase MC3T3-E1 matrix mineralization and Pi influx associated with activation of both Pit-1 and Pit-2 channels, with significantly increased Pit-2 production. In contrast, Pi transport elicited by rhBMP-2 showed to be associated with increased Pit-1 production only. Next, neutralizing antibodies against Pit-1 and Pit-2 completely abrogated the Pi influx effect of rhNELL-1, suggesting rhNELL-1 is dependent on both transporters. These results identify one potential mechanism of action for rhNELL-1 induced osteogenesis and highlight a fundamental difference between NELL-1 and BMP-2 signaling.

  7. A lunar transportation system

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Due to large amounts of oxygen required for space travel, a method of mining, transporting, and storing this oxygen in space would facilitate further space exploration. The following project deals specifically with the methods for transporting liquid oxygen from the lunar surface to the Lunar Orbit (LO) space station, and then to the Lower Earth Orbit (LEO) space station. Two vehicles were designed for operation between the LEO and LO space stations. The first of these vehicles is an aerobraked design vehicle. The Aerobrake Orbital Transfer Vehicle (OTV) is capable of transporting 5000 lbm of payload to LO while returning to LEO with 60,000 lbm of liquid oxygen, and thus meet mission requirements. The second vehicle can deliver 18,000 lbm of payload to LO and is capable of bringing 60,000 lbm of liquid oxygen back to LEO. A lunar landing vehicle was also designed for operation between LO and the established moon base. The use of an electromagnetic railgun as a method for launching the lunar lander was also investigated. The feasibility of the railgun is doubtful at this time. A system of spheres was also designed for proper storing and transporting of the liquid oxygen. The system assumes a safe means for transferring the liquid oxygen from tank to tank is operational. A sophisticated life support system was developed for both the OTV and the lunar lander. This system focuses on such factors as the vehicle environment, waste management, water requirements, food requirements, and oxygen requirements.

  8. Lunar transportation system

    NASA Technical Reports Server (NTRS)

    1993-01-01

    The University Space Research Association (USRA) requested the University of Minnesota Spacecraft Design Team to design a lunar transportation infrastructure. This task was a year long design effort culminating in a complete conceptual design and presentation at Johnson Space Center. The mission objective of the design group was to design a system of vehicles to bring a habitation module, cargo, and crew to the lunar surface from LEO and return either or both crew and cargo safely to LEO while emphasizing component commonality, reusability, and cost effectiveness. During the course of the design, the lunar transportation system (LTS) has taken on many forms. The final design of the system is composed of two vehicles, a lunar transfer vehicle (LTV) and a lunar excursion vehicle (LEV). The LTV serves as an efficient orbital transfer vehicle between the earth and the moon while the LEV carries crew and cargo to the lunar surface. Presented in the report are the mission analysis, systems layout, orbital mechanics, propulsion systems, structural and thermal analysis, and crew systems, avionics, and power systems for this lunar transportation concept.

  9. Transportation Systems Center

    SciTech Connect

    Greer, G.S.

    1992-07-01

    The Transportation Systems Center at Sandia Laboratory performs research, development, and implementation of technologies that enhance the safe movement of people, goods, and information. Our focus is on systems engineering. However, we realize that to understand the puzzle, you must also understand the pieces. This brochure describes some of the activities currently underway at the Center and presents the breadth and depth of our capabilities. Please contact the noted, individuals for more, information.

  10. Heat transport system

    DOEpatents

    Pierce, Bill L.

    1978-01-01

    A heat transport system of small size which can be operated in any orientation consists of a coolant loop containing a vaporizable liquid as working fluid and includes in series a vaporizer, a condenser and two one-way valves and a pressurizer connected to the loop between the two valves. The pressurizer may be divided into two chambers by a flexible diaphragm, an inert gas in one chamber acting as a pneumatic spring for the system.

  11. Effect of Phosphate and Uncouplers on Substrate Transport and Oxidation by Isolated Corn Mitochondria 1

    PubMed Central

    Day, David A.; Hanson, John B.

    1977-01-01

    A study was made to determine conditions under which malate oxidation rates in corn (Zea mays L.) mitochondria are limited by transport processes. In the absence of added ADP, inorganic phosphate increased malate oxidation rates by processes inhibited by mersalyl and oligomycin, but phosphate did not stimulate uncoupled respiration. However, the uncoupled oxidation rates were inhibited by butylmalonate and mersalyl. When uncoupler was added prior to substrate, subsequent O2 uptake rates were reduced when malate and succinate, but not exogenous NADH, were used. Uncoupler and butylmalonate also inhibited swelling in malate solutions and malate accumulation by these mitochondria, which were found to have a high endogenous phosphate content. Addition of uncoupler after malate or succinate produced an initial rapid oxidation which declined as the mitochondria lost solute and contracted. This decline was not affected by addition of ADP or AMP, and was not observed when exogenous NADH was substrate. Increasing K+ permeability with valinomycin increased the P-trifluoromethoxy (carboxylcyanide)phenyl hydrazone inhibition. Kinetic studies showed the slow rate of malate oxidation in the presence of uncoupler to be characterized by a high Km and a low Vmax, probably reflecting a diffusion-limited process. The results indicate that rapid malate and succinate oxidation require the operation of both the phosphate and dicarboxylate transporters, which in turn depend on maintenance of a proton motive force across the inner membrane. In addition, phosphate can stimulate acceptorless malate oxidation by reaction with the coupling mechanism, and in uncoupled mitochondria which are depleted of substrate there is a slow rate of oxidation which appears to be limited by diffusive entry. PMID:16659803

  12. The journey from vitamin D-resistant rickets to the regulation of renal phosphate transport.

    PubMed

    Levine, Barton S; Kleeman, Charles R; Felsenfeld, Arnold J

    2009-11-01

    In 1937, Fuller Albright first described two rare genetic disorders: Vitamin D resistant rickets and polyostotic fibrous dysplasia, now respectively known as X-linked hypophosphatemic rickets (XLH) and the McCune-Albright syndrome. Albright carefully characterized and meticulously analyzed one patient, W.M., with vitamin D-resistant rickets. Albright subsequently reported additional carefully performed balance studies on W.M. In this review, which evaluates the journey from the initial description of vitamin D-resistant rickets (XLH) to the regulation of renal phosphate transport, we (1) trace the timeline of important discoveries in unraveling the pathophysiology of XLH, (2) cite the recognized abnormalities in mineral metabolism in XLH, (3) evaluate factors that may affect parathyroid hormone values in XLH, (4) assess the potential interactions between the phosphate-regulating gene with homology to endopeptidase on the X chromosome and fibroblast growth factor 23 (FGF23) and their resultant effects on renal phosphate transport and vitamin D metabolism, (5) analyze the complex interplay between FGF23 and the factors that regulate FGF23, and (6) discuss the genetic and acquired disorders of hypophosphatemia and hyperphosphatemia in which FGF23 plays a role. Although Albright could not measure parathyroid hormone, he concluded on the basis of his studies that showed calcemic resistance to parathyroid extract in W.M. that hyperparathyroidism was present. Using a conceptual approach, we suggest that a defect in the skeletal response to parathyroid hormone contributes to hyperparathyroidism in XLH. Finally, at the end of the review, abnormalities in renal phosphate transport that are sometimes found in patients with polyostotic fibrous dysplasia are discussed. PMID:19808223

  13. Responses of Phosphate Transporter Gene and Alkaline Phosphatase in Thalassiosira pseudonana to Phosphine

    PubMed Central

    Fu, Mei; Song, Xiuxian; Yu, Zhiming; Liu, Yun

    2013-01-01

    Phosphine, which is released continuously from sediment, can affect the eco-physiological strategies and molecular responses of phytoplankton. To examine the effects of phosphine on phosphorus uptake and utilization in Thalassiosira pseudonana, we examined the transcriptional level of the phosphate transporter gene (TpPHO) and the activity of alkaline phosphatase (AKP) in relation to supplement of various concentrations of phosphine. TpPHO expression was markedly promoted by phosphine in both the phosphate-deficient and phosphate-4 µM culture. However, high phosphine concentrations can inhibit TpPHO transcription in the declining growth phase. AKP activity was also higher in the phosphine treatment groups than that of the control. It increased with increasing phosphine concentration in the range of 0 to 0.056 µM but was inhibited by higher levels of phosphine. These responses revealed that phosphine can affect phosphate uptake and utilization in T. pseudonana. This result was consistent with the effect of phosphine on algal growth, while TpPHO expression and AKP were even more sensitive to phosphine than algal growth. This work provides a basic understanding for further research about how phosphine affects phytoplankton. PMID:23544096

  14. The Role of Sarcolipin and ATP in the Transport of Phosphate Ion into the Sarcoplasmic Reticulum

    PubMed Central

    Becucci, Lucia; Guidelli, Rolando; Karim, Christine B.; Thomas, David D.; Veglia, Gianluigi

    2009-01-01

    Abstract In a previous study, sarcolipin (SLN) was shown to form channels selective toward chloride ion when incorporated in a mercury-supported tethered bilayer lipid membrane (tBLM). Its incorporation had only a modest permeabilizing effect on phosphate ion. In this note the resistance of a tBLM membrane incorporating sarcolipin was investigated by electrochemical impedance spectroscopy in aqueous solutions of 0.05 M sodium phosphate of pH ranging from 5.3 to 8, in the presence of ATP, adenosine monophosphate, and phenylphosphonic acid. At pH 5.3, submicromolar additions of ATP increase the conductivity of the tBLM incorporating SLN up to a maximum limiting value. The dependence of the conductivity on the ATP concentration satisfies the Michaelis-Menten equation, with an association constant of 0.1 μM. Phenylphosphonium ion and adenosine monophosphate exert an inhibitory effect on membrane permeabilization to phosphate ions by ATP if they are added before ATP, but not if they are added after it. An explanation for this behavior is provided. In conclusion, SLN acts as an ATP-induced phosphate carrier exhibiting a behavior quite similar to that of the unidentified Pi transporter described previously. No ion-channel activity is exhibited by the T18A mutant of SLN. PMID:19917222

  15. Divalent phosphate is a counterion for carboxyatractyloside-insensitive adenine nucleotide transport in rat liver mitochondria

    SciTech Connect

    Nosek, M.T.; Aprille, J.R.

    1986-05-01

    Unidirectional, carboxyatractyloside(CAT)-insensitive adenine nucleotide (AdN) fluxes have been studied in isolated rat liver mitochondria (mito). Previous work has shown that ATP x Mg transport in one direction is coupled to ATP x Mg or P/sub i/ transport in the opposite direction. The purpose of this study was to determine whether divalent HPO/sub 4//sup 2 -/ or monovalent H/sub 2/PO/sub 4//sup -/ is the transported phosphate species. The authors used the monofluorophosphate (PO/sub 3/F/sup 2 -/) and difluorophosphate (PO/sub 2/F/sub 2//sup -/) analogues as potential counterions forAdN efflux. After a preincubation on ice with /sup 14/C-ADP to label the matrix AdN, efflux was measured at 30/sup 0/C, pH 7.4, in 225mM sucrose, 10mM KCl, 5mM MgCl/sub 2/, 5mM glutamate, 5mM malate, 10mM Tris, 0.5mM P/sub i/, 1mM ATP, and 5..mu..M CAT. With no other additions efflux was -0.62 +/- 0.20 nmole/minute/mg protein. The data supports the hypothesis that divalent but not monovalent phosphate can act as a counterion for ATPx Mg transport over this CAT-insensitive carrier.

  16. Mars Equipment Transport System

    NASA Astrophysics Data System (ADS)

    Sorrells, Cindy; Geiger, Michelle; Ohanlon, Sean; Pieloch, Stuart; Brogan, Nick

    1993-12-01

    Mechanical Engineering Senior Design Project 1 (ME4182) is a part of the NASA/University Advanced Design Program. Under this program, NASA allocates money and resources to students to be used in design work for a specified topic. The current topic is the exploration and colonization of Mars. The specific area in which we are to work is the transportation of the modules in which astronauts will live while on Mars. NASA is concerned about the weight of the module transferring system, as the shipping cost to Mars is quite expensive. NASA has specified that the weight of the system is to be minimized in order to reduce the shipping costs.

  17. Mars Equipment Transport System

    NASA Technical Reports Server (NTRS)

    Sorrells, Cindy; Geiger, Michelle; Ohanlon, Sean; Pieloch, Stuart; Brogan, Nick

    1993-01-01

    Mechanical Engineering Senior Design Project 1 (ME4182) is a part of the NASA/University Advanced Design Program. Under this program, NASA allocates money and resources to students to be used in design work for a specified topic. The current topic is the exploration and colonization of Mars. The specific area in which we are to work is the transportation of the modules in which astronauts will live while on Mars. NASA is concerned about the weight of the module transferring system, as the shipping cost to Mars is quite expensive. NASA has specified that the weight of the system is to be minimized in order to reduce the shipping costs.

  18. Space Transportation Systems Technologies

    NASA Technical Reports Server (NTRS)

    Laue, Jay H.

    2001-01-01

    This document is the final report by the Science Applications International Corporation (SAIC) on contracted support provided to the National Aeronautics and Space Administration (NASA) under Contract NAS8-99060, 'Space Transportation Systems Technologies'. This contract, initiated by NASA's Marshall Space Flight Center (MSFC) on February 8, 1999, was focused on space systems technologies that directly support NASA's space flight goals. It was awarded as a Cost-Plus-Incentive-Fee (CPIF) contract to SAIC, following a competitive procurement via NASA Research Announcement, NRA 8-21. This NRA was specifically focused on tasks related to Reusable Launch Vehicles (RLVs). Through Task Area 3 (TA-3), "Other Related Technology" of this NRA contract, SAIC extensively supported the Space Transportation Directorate of MSFC in effectively directing, integrating, and setting its mission, operations, and safety priorities for future RLV-focused space flight. Following an initially contracted Base Year (February 8, 1999 through September 30, 1999), two option years were added to the contract. These were Option Year 1 (October 1, 1999 through September 30, 2000) and Option Year 2 (October 1, 2000 through September 30, 2001). This report overviews SAIC's accomplishments for the Base Year, Option Year 1, and Option Year 2, and summarizes the support provided by SAIC to the Space Transportation Directorate, NASA/MSFC.

  19. Magnetically Coupled Transport System

    SciTech Connect

    Breshears, S.A.

    1999-01-26

    Throughout the DOE complex, materials are routinely transported within glovebox processing lines. Cylindrical product cans, crucibles, sample containers, tools, and waste products are all examples of items that are moved between equipment stations during glovebox operations. Traditional transport methods have included manual handling using tongs, chain and belt conveyors, carts with pull wires, and overhead hoists on monorails. These methods rely on hands-on operations and/or utilize high maintenance equipment located inside the gloveboxes, which can lead to high radiation exposure to personnel and can generate large amounts of radioactive waste. One innovative approach incorporates linear induction motors (LIMs) so that high maintenance items are located outside the gloveboxes, but LIMs produce heat, do not move smoothly over a wide range of velocities, and are not locked in position at zero velocity. Savannah River Technology Center (SRTC) engineers have developed and demonstrated a concept for a magnetically coupled transport system to transfer material within process lines and from line to line. This automated system significantly reduces hands-on operations. Linear actuators and lead screws provide smooth horizontal and vertical movement. Rare earth magnetic coupling technology allows the majority of the equipment to be located outside the glovebox, simplifying maintenance and minimizing radioactive waste.

  20. Mars transportation system

    NASA Technical Reports Server (NTRS)

    Garrard, William; Vano, Andrew; Rutherford, Dave

    1992-01-01

    The University of Minnesota Advanced Space Design Program has developed a sample Mars exploration scenario. The purpose of the design project is to enhance NASA and university interaction, to provide fresh ideas to NASA, and to provide real world design problems to engineering students. The Mars Transportation System in this paper is designed to transport a crew of six astronauts to the Martian surface and return them to Low Earth Orbit (LEO) starting in the year 2016. The proposed vehicle features such advanced technologies as nuclear propulsion, nuclear power generation, and aerobraking. Three missions are planned. Orbital trajectories are of the conjunction class with an inbound Venus swingby providing a 60-day surface stay at Mars and an average total trip time of 520 days.

  1. Phosphate Concentration and Arbuscular Mycorrhizal Colonisation Influence the Growth, Yield and Expression of Twelve PHT1 Family Phosphate Transporters in Foxtail Millet (Setaria italica)

    PubMed Central

    Ceasar, S. Antony; Hodge, Angela; Baker, Alison; Baldwin, Stephen A.

    2014-01-01

    Phosphorus (P) is an essential element which plays several key roles in all living organisms. Setaria italica (foxtail millet) is a model species for panacoid grasses including several millet species widely grown in arid regions of Asia and Africa, and for the bioenergy crop switchgrass. The growth responses of S. italica to different levels of inorganic phosphate (Pi) and to colonisation with the arbuscular mycorrhizal fungus Funneliformis mosseae (syn. Glomus mosseae) were studied. Phosphate is taken up from the environment by the PHT1 family of plant phosphate transporters, which have been well characterized in several plant species. Bioinformatic analysis identified 12 members of the PHT1 gene family (SiPHT1;1-1;12) in S. italica, and RT and qPCR analysis showed that most of these transporters displayed specific expression patterns with respect to tissue, phosphate status and arbuscular mycorrhizal colonisation. SiPHT1;2 was found to be expressed in all tissues and in all growth conditions tested. In contrast, expression of SiPHT1;4 was induced in roots after 15 days growth in hydroponic medium of low Pi concentration. Expression of SiPHT1;8 and SiPHT1;9 in roots was selectively induced by colonisation with F. mosseae. SiPHT1;3 and SiPHT1;4 were found to be predominantly expressed in leaf and root tissues respectively. Several other transporters were expressed in shoots and leaves during growth in low Pi concentrations. This study will form the basis for the further characterization of these transporters, with the long term goal of improving the phosphate use efficiency of foxtail millet. PMID:25251671

  2. Mars transportation system synthesis

    NASA Astrophysics Data System (ADS)

    Young, Archie C.; Mulqueen, John A.; Emrich, William J.

    Performance and requirements synthesized to support the manned Mars mission of the Space Exploration Initiative (SEI) are presented. Emphasis is placed on the Mars transportation system (MTS), which uses nuclear thermal rocket (NTR) propulsion technology associated with accomplishing the manned Mars mission. Data are also presented for a propulsion system options comparison of chemical/aerobrake and nuclear electric propulsion systems. Vehicle- and weight-scaling are used to determine the MTS mass, size, and performance range required for different Mars mission durations. The split sprint, opposition, and conjunction class mission modes are employed to determine the MTS requirements envelope. MTS sensitivity to Mars surface payload, crew size, Mars orbit payload, NTR engine thrust level, engine specific impulse, and NTR engine thrust-to-weight ratio are synthesized. A suggested NTR technology level to accomplish both cargo and piloted Mars missions is discussed.

  3. Uptake and transport of roxarsone and its metabolites in water spinach as affected by phosphate supply.

    PubMed

    Yao, Lixian; Li, Guoliang; Dang, Zhi; Yang, Baomei; He, Zhaohuan; Zhou, Changmin

    2010-04-01

    Roxarsone (ROX) is widely used as a feed additive in intensive animal production. While an animal is fed with ROX, the As compounds in the manure primarily occur as ROX and its metabolites, including arsenate (As[V]), arsenite (As[III]), monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA). Animal manure is commonly land applied with phosphorous fertilizers in China. A pot experiment was conducted to investigate the phytoavailability of ROX, As(V), As(III), MMA, and DMA in water spinach (Ipomoea aquatica), with the soil amended with 0, 0.25, 0.50, 1.0, and 2.0 g PO(4)/kg, respectively, plus 2% (w/w manure/soil) chicken manure (CM) bearing ROX and its metabolites. The results indicate that this species of water spinach cannot accumulate ROX and MMA at detectable levels, but As(V), As(III), and DMA were present in all plant samples. Increased phosphorous decreased the shoot As(V) and As(III) in water spinach but did not affect the root As(V). The shoot DMA and root As(III) and DMA were decreased/increased and then increased/decreased by elevated phosphorous. The total phosphorous content (P) in plant tissue did not correlate with the total As or the three As species in tissues. Arsenate, As(III), and DMA were more easily accumulated in the roots, and phosphate considerably inhibited their upward transport. Dimethylarsinic acid had higher transport efficiency than As(V) and As(III), but As(III) was dominant in tissues. Conclusively, phosphate had multiple effects on the accumulation and transport of ROX metabolites, which depended on their levels. However, proper utilization of phosphate fertilizer can decrease the accumulation of ROX metabolites in water spinach when treated with CM containing ROX and its metabolites. PMID:20821525

  4. Alternate transportation system

    NASA Technical Reports Server (NTRS)

    Zertuche, Tony; Mckinnie, James

    1988-01-01

    Three missions have been identified by NASA for a Space Shuttle-supplementing Alternate Transportation System (ATS) encompassing combinations of booster vehicles, crew modules, and service modules: (1) to achieve manned access to orbit for Space Station crew rotation every 90 days, (2) the lofting of a logistics module resupplying the Space Station every 180 days, and (3) the simultaneous launch of both crews and logistics to the Space Station. A reentry glider is considered, in conjunction with the Space Shuttle's unmanned cargo version and the Apollo manned capsule, as an important ATS element. The Titan IV/NUS is used as a booster.

  5. Pneumatic Pellet-Transporting System

    NASA Technical Reports Server (NTRS)

    Wood, George; Pugsley, Robert A.

    1992-01-01

    Pneumatic system transports food pellets to confined animals. Flow of air into venturi assembly entrains round pellets, drawing them from reservoir into venturi for transport by airflow. Pneumatic pellet-transporting system includes venturi assembly, which creates flow of air that draws pellets into system.

  6. Comparative uptake kinetics and transport of cadmium and phosphate in Phleum pratense-Glomus deserticolum associations

    SciTech Connect

    Arnold, P.T.; Kapustka, L.A. )

    1993-01-01

    Mycorrhizal plants (timothy grass, Phleum pretense with Glomus deserticolum) were compared to nonmycorrhizal timothy grass to determine the effect of the mycorrhizal condition on the uptake and transport of cadmium. Companion experiments were conducted to ascertain phosphate uptake kinetics of mycorrhizal and nonmycorrhizal plants. Divalent cation competition experiments also were employed in this study. Comparisons of the high-affinity uptake mechanisms between mycorrhizal and nonmycorrhizal plants identified higher levels of phosphate uptake were due to an increase in the number of uptake sites rather than to differences in affinity. The respective values for K[sub m] for high-affinity phosphate uptake were 2.5 [plus minus] 1.3 [mu]MP (mycorrhizal) and 3.4 [plus minus] 1.3 [mu]MP (nonmycorrhizal), but these values were not statistically different at the [alpha] = 0.05 level. High-affinity Cd[sup 2+] uptake differed significantly between mycorrhizal (4.5 [plus minus] 2.8 [mu]M) and nonmycorrhizal (2.8 [plus minus] 1.1 [mu]M) plants. Presence of Ca[sup 2+] at 1.0mM concentration conferred considerable competitive protection in both the mycorrhizal and the nonmycorrhizal conditions. The effect of Ca[sup 2+] was an approximate fourfold increase in the respective K[sub m] values.

  7. Two differentially regulated phosphate transporters from the symbiotic fungus Hebeloma cylindrosporum and phosphorus acquisition by ectomycorrhizal Pinus pinaster.

    PubMed

    Tatry, Marie-Violaine; El Kassis, Elie; Lambilliotte, Raphaël; Corratgé, Claire; van Aarle, Ingrid; Amenc, Laurie K; Alary, Rémi; Zimmermann, Sabine; Sentenac, Hervé; Plassard, Claude

    2009-03-01

    Ectomycorrhizal symbiosis markedly improves plant phosphate uptake, but the molecular mechanisms underlying this benefit are still poorly understood. We identified two ESTs in a cDNA library prepared from the ectomycorrhizal basidiomycete Hebeloma cylindrosporum with significant similarities to phosphate transporters from the endomycorrhizal fungus Glomus versiforme and from non-mycorrhizal fungi. The full-length cDNAs corresponding to these two ESTs complemented a yeast phosphate transport mutant (Deltapho84). Measurements of (33)P-phosphate influx into yeast expressing either cDNA demonstrated that the encoded proteins, named HcPT1 and HcPT2, were able to mediate Pi:H(+) symport with different affinities for Pi (K(m) values of 55 and 4 mum, respectively). Real-time RT-PCR showed that Pi starvation increased the levels of HcPT1 transcripts in H. cylindrosporum hyphae grown in pure culture. Transcript levels of HcPT2 were less dependent on Pi availability. The two transporters were expressed in H. cylindrosporum associated with its natural host plant, Pinus pinaster, grown under low or high P conditions. The presence of ectomycorrhizae increased net Pi uptake rates into intact Pinus pinaster roots at low or high soil P levels. The expression patterns of HcPT1 and HcPT2 indicate that the two fungal phosphate transporters may be involved in uptake of phosphate from the soil solution under the two soil P availability conditions used. PMID:19054369

  8. Modulation of small intestinal phosphate transporter by dietary supplements of mineral phosphorus and phytase in broilers.

    PubMed

    Huber, Korinna; Zeller, Ellen; Rodehutscord, Markus

    2015-05-01

    Dietary phosphorus (P) is known as a main modulator of phosphate (Pi) transporter expression. The effect of supplemented mineral P with or without phytase on protein expression of two sodium-dependent Pi (NaPi) transporters and a calcium channel was studied in the small intestine of broilers. Thirty-six broilers were randomly assigned to six different diets at 15 days of age. Two levels of total P (tP, adjusted by monocalcium phosphate (MCP) supplementation), 0.39% (BD-) and 0.47% (BD+) were fed until day 25; and at each tP level, three levels of phytase were used with 0, 500, and 12,500 FTU/kg of an E. coli phytase. Mucosa samples from jejunum and ileum were taken and apical membranes were isolated by MgCl2 precipitation. Protein expression of NaPi IIb, NaPi type III (PiT1) and the calcium channel TRPV6 were semiquantitatively measured by Western blotting and jejunal mucosal phytase activity by measurement of Pi release. The jejunal NaPi IIb transporter was expressed with two distinct bands, which were modulated differently by diet. NaPi IIb Band1 increased (P < 0.05) and Band2 decreased (P < 0.05) with phytase supplementation but was not affected by MCP supplementation. This inverse modulation of Band1 and Band2 was significantly related to the amount of net absorbed P with higher expression of Band1 at higher amounts of net absorbed P. In addition, a second Pi transporter, PiT1, was detected in which ileal expression decreased (P < 0.05) in response to higher phytase supplementation. The expression of the calcium channel TRPV6 was increased in BD+ groups. A trend for an interaction between MCP and phytase supplementation on mucosal phytase activity was observed (P = 0.079) with a decrease in activity when BD+ with 12,500 FTU/kg phytase was fed. Chicken intestinal epithelial cells responded to dietary supplemented phytase and MCP by changing the Pi transporter expression in apical membranes. In conclusion, availability of Pi is most likely the key modulator of

  9. 21 CFR 862.1315 - Galactose-1-phosphate uridyl transferase test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1315 Galactose-1-phosphate uridyl transferase test system. (a)...

  10. 21 CFR 862.1315 - Galactose-1-phosphate uridyl transferase test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1315 Galactose-1-phosphate uridyl transferase test system. (a)...

  11. Isolation and characterization of a sodium-dependent phosphate transporter gene in Dunaliella viridis.

    PubMed

    Li, Qiyun; Gao, Xiaoshu; Sun, Yu; Zhang, Qingqi; Song, Rentao; Xu, Zhengkai

    2006-02-01

    A sodium-dependent phosphate transporter gene, DvSPT1, was isolated from a cDNA library using a probe derived from a subtracted cDNA library of Dunaliella viridis. Sequencing analyses revealed a cDNA sequence of 2649 bp long and encoded an open-reading frame consisting of 672 amino acids. The deduced amino acid sequence of DvSPT1 exhibited 31.2% identity to that of TcPHO from Tetraselmis chui. Hydrophobicity and secondary structure prediction revealed 11 conserved transmembrane domains similar to those found in PHO89 from Saccharomyces cerevisiae and PHO4 from Neurospora crassa. Northern blot analysis indicated that the DvSPT1 expression was induced upon NaCl hyperosmotic stress or phosphate depletion. Functional characterization in yeast Na+ export pump mutant G19 suggested that DvSPT1 encoded a Na+ transporter protein. The gene sequence of GDvSPT1 (7922 bp) was isolated from a genomic library of D. viridis. Southern blot analysis indicated that there exist at least two homologous genes in D. viridis. PMID:16359638

  12. Transportation System Concept of Operations

    SciTech Connect

    N. Slater-Thompson

    2006-08-16

    The Nuclear Waste Policy Act of 1982 (NWPA), as amended, authorized the DOE to develop and manage a Federal system for the disposal of SNF and HLW. OCRWM was created to manage acceptance and disposal of SNF and HLW in a manner that protects public health, safety, and the environment; enhances national and energy security; and merits public confidence. This responsibility includes managing the transportation of SNF and HLW from origin sites to the Repository for disposal. The Transportation System Concept of Operations is the core high-level OCRWM document written to describe the Transportation System integrated design and present the vision, mission, and goals for Transportation System operations. By defining the functions, processes, and critical interfaces of this system early in the system development phase, programmatic risks are minimized, system costs are contained, and system operations are better managed, safer, and more secure. This document also facilitates discussions and understanding among parties responsible for the design, development, and operation of the Transportation System. Such understanding is important for the timely development of system requirements and identification of system interfaces. Information provided in the Transportation System Concept of Operations includes: the functions and key components of the Transportation System; system component interactions; flows of information within the system; the general operating sequences; and the internal and external factors affecting transportation operations. The Transportation System Concept of Operations reflects OCRWM's overall waste management system policies and mission objectives, and as such provides a description of the preferred state of system operation. The description of general Transportation System operating functions in the Transportation System Concept of Operations is the first step in the OCRWM systems engineering process, establishing the starting point for the lower level

  13. Phosphate transporters OsPHT1;9 and OsPHT1;10 are involved in phosphate uptake in rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We characterized the function of two rice phosphate (Pi) transporters: OsPHT1;9 (OsPT9) and OsPHT1;10 (OsPT10). OsPT9 and OsPT10 were expressed in the root epidermis, root hairs, and lateral roots, with the expression being specifically induced by Pi-starvation. In leaves, the expression of the two ...

  14. Phosphate transporters in marine phytoplankton and their viruses: cross-domain commonalities in viral-host gene exchanges.

    PubMed

    Monier, Adam; Welsh, Rory M; Gentemann, Chelle; Weinstock, George; Sodergren, Erica; Armbrust, E Virginia; Eisen, Jonathan A; Worden, Alexandra Z

    2012-01-01

    Phosphate (PO(4)) is an important limiting nutrient in marine environments. Marine cyanobacteria scavenge PO(4) using the high-affinity periplasmic phosphate binding protein PstS. The pstS gene has recently been identified in genomes of cyanobacterial viruses as well. Here, we analyse genes encoding transporters in genomes from viruses that infect eukaryotic phytoplankton. We identified inorganic PO(4) transporter-encoding genes from the PHO4 superfamily in several virus genomes, along with other transporter-encoding genes. Homologues of the viral pho4 genes were also identified in genome sequences from the genera that these viruses infect. Genome sequences were available from host genera of all the phytoplankton viruses analysed except the host genus Bathycoccus. Pho4 was recovered from Bathycoccus by sequencing a targeted metagenome from an uncultured Atlantic Ocean population. Phylogenetic reconstruction showed that pho4 genes from pelagophytes, haptophytes and infecting viruses were more closely related to homologues in prasinophytes than to those in what, at the species level, are considered to be closer relatives (e.g. diatoms). We also identified PHO4 superfamily members in ocean metagenomes, including new metagenomes from the Pacific Ocean. The environmental sequences grouped with pelagophytes, haptophytes, prasinophytes and viruses as well as bacteria. The analyses suggest that multiple independent pho4 gene transfer events have occurred between marine viruses and both eukaryotic and bacterial hosts. Additionally, pho4 genes were identified in available genomes from viruses that infect marine eukaryotes but not those that infect terrestrial hosts. Commonalities in marine host-virus gene exchanges indicate that manipulation of host-PO(4) uptake is an important adaptation for viral proliferation in marine systems. Our findings suggest that PO(4) -availability may not serve as a simple bottom-up control of marine phytoplankton. PMID:21914098

  15. Phosphate transporters in marine phytoplankton and their viruses: cross-domain commonalities in viral-host gene exchanges

    PubMed Central

    Monier, Adam; Welsh, Rory M; Gentemann, Chelle; Weinstock, George; Sodergren, Erica; Armbrust, E Virginia; Eisen, Jonathan A; Worden, Alexandra Z

    2012-01-01

    Phosphate (PO4) is an important limiting nutrient in marine environments. Marine cyanobacteria scavenge PO4 using the high-affinity periplasmic phosphate binding protein PstS. The pstS gene has recently been identified in genomes of cyanobacterial viruses as well. Here, we analyse genes encoding transporters in genomes from viruses that infect eukaryotic phytoplankton. We identified inorganic PO4 transporter-encoding genes from the PHO4 superfamily in several virus genomes, along with other transporter-encoding genes. Homologues of the viral pho4 genes were also identified in genome sequences from the genera that these viruses infect. Genome sequences were available from host genera of all the phytoplankton viruses analysed except the host genus Bathycoccus. Pho4 was recovered from Bathycoccus by sequencing a targeted metagenome from an uncultured Atlantic Ocean population. Phylogenetic reconstruction showed that pho4 genes from pelagophytes, haptophytes and infecting viruses were more closely related to homologues in prasinophytes than to those in what, at the species level, are considered to be closer relatives (e.g. diatoms). We also identified PHO4 superfamily members in ocean metagenomes, including new metagenomes from the Pacific Ocean. The environmental sequences grouped with pelagophytes, haptophytes, prasinophytes and viruses as well as bacteria. The analyses suggest that multiple independent pho4 gene transfer events have occurred between marine viruses and both eukaryotic and bacterial hosts. Additionally, pho4 genes were identified in available genomes from viruses that infect marine eukaryotes but not those that infect terrestrial hosts. Commonalities in marine host-virus gene exchanges indicate that manipulation of host-PO4 uptake is an important adaptation for viral proliferation in marine systems. Our findings suggest that PO4-availability may not serve as a simple bottom-up control of marine phytoplankton. PMID:21914098

  16. The influence of hypothyroidism on the transport of phosphate and on the lipid composition in rat-liver mitochondria.

    PubMed

    Paradies, G; Ruggiero, F M; Dinoi, P

    1991-11-18

    The influence of hypothyroidism on the transport of phosphate and on the lipid composition in rat-liver mitochondria was examined. It was found that the rate of phosphate transport is reduced (around 40%) in mitochondria from hypothyroid rats compared to that obtained in mitochondria from normal rats. Treatment of hypothyroid rats with thyroid hormone reverses this effect completely. Kinetic analysis of the phosphate transport indicates that only the Vmax of this process is affected, while there is no change in the Km values. The lower rate of phosphate transport in mitochondria from hypothyroid rats is also demonstrated by swelling experiments. There is no significant difference either in the respiratory control ratios or in the ADP/O ratios between these two types of mitochondria. The hepatic mitochondrial lipid composition is altered significantly in hypothyroid rats. The total cholesterol increases, the phospholipids decrease and the cholesterol/phospholipid molar ratio increases (around 40%). Among the phospholipids, cardiolipin shows the greatest alteration (30% decrease in the hypothyroid rats). The phosphatidylethanolamine/phosphatidylcholine ratio also decreases. Alterations were also found in the pattern of fatty acids. These changes in lipid composition may be responsible, at least in part, for the depression of the phosphate carrier activity in mitochondria from hypothyroid rats. PMID:1751524

  17. Influence of phosphate on the transport properties of lead in sand.

    PubMed

    Butkus, Michael A; Johnson, Marie C

    2011-01-15

    Temporal moment analysis was used to examine the transport of lead species in sand columns. The influence of sodium phosphate (PO(4(aq))) and hydroxyapatite (HA) on lead transport was also evaluated. Transport properties of lead microparticles (diameter>0.45 μm) were a function of electrophoretic mobility: those particles with electrophoretic mobility less than -1 × 10(-8)m(2)/Vs exhibited significantly lower dimensionless first temporal moment (θ) and second temporal moment (σ(θ)(2)). The forms of lead investigated in this work had a tendency to move in sand over a wide pH range. Although the PO(4(aq)) amendment substantially reduced lead mass recoveries in the sand column effluent, lead microparticles were formed that had a tendency to move rapidly and with minimal dispersion when compared with controls. Treatments with HA provided limited reduction in lead mass recovery and minimal changes in lead transport properties. A colloid stability model was used to predict attachment of lead particles in sand. PMID:20934809

  18. LA-ICP-MS analysis of isolated phosphatic grains indicates selective rare earth element enrichment during reworking and transport processes

    NASA Astrophysics Data System (ADS)

    Auer, Gerald; Reuter, Markus; Hauzenberger, Christoph A.; Piller, Werner E.

    2016-04-01

    water chemistry under certain well constrained circumstances of primary authigenesis. Are these conditions not met, REE patterns are more likely to reflect complex enrichment processes that likely already started to occur during reworking over geologically relatively short time frames. Similarities in the REE patterns of clearly detrital and biogenic phosphate further suggest that the often observed 'hat-shaped' pattern in biogenic phosphates can easily result from increased middle REE (Neodymium to Holmium) scavenging during taphonomic processes prior to final deposition. Finally, cluster analysis coupled with sedimentological considerations proved a valuable tool for the characterization of REE patterns of phosphates in terms of their formation conditions and depositional history, such as the distinction of phosphates formed in situ from reworked and transported phosphate grains.

  19. Characterization of the Rhizobium (Sinorhizobium) meliloti high- and low-affinity phosphate uptake systems.

    PubMed Central

    Voegele, R T; Bardin, S; Finan, T M

    1997-01-01

    Genetic studies have suggested that Rhizobium (Sinorhizobium) meliloti contains two distinct phosphate (Pi) transport systems, encoded by the phoCDET genes and the orfA-pit genes, respectively. Here we present data which show that the ABC-type PhoCDET system has a high affinity for Pi (Km, 0.2 microM) and that Pi uptake by this system is severely inhibited by phosphonates. This high-affinity uptake system was induced under Pi-limiting conditions and was repressed in the presence of excess Pi. Uptake via the OrfA-Pit system was examined in (i) a phoC mutant which showed increased expression of the orfA-pit genes as a result of a promoter-up mutation and (ii) a phoB mutant (PhoB is required for phoCDET expression). Pi uptake in both strains exhibited saturation kinetics (Km, 1 to 2 microM) and was not inhibited by phosphonates. This uptake system was active in wild-type cells grown with excess Pi and appeared to be repressed when the cells were starved for Pi. Thus, our biochemical data show that the OrfA-Pit and PhoCDET uptake systems are differentially expressed depending on the state of the cell with respect to phosphate availability. PMID:9393684

  20. Stimulation of the intestinal phosphate transporter SLC34A2 by the protein kinase mTOR.

    PubMed

    Shojaiefard, Manzar; Lang, Florian

    2006-07-14

    Adequate phosphate homeostasis is of critical importance for a wide variety of functions including bone mineralization and energy metabolism. Phosphate balance is a function of intestinal absorption and renal elimination, which are both under tight hormonal control. Intestinal phosphate absorption is accomplished by the Na(+), phosphate cotransporter NaPi IIb (SLC34A2). Signaling mechanisms mediating hormonal regulation of SLC34A2 are incompletely understood. The mammalian target of rapamycin (mTOR) is a kinase regulating a variety of nutrient transporters. The present experiments explored whether mTOR regulates the activity of SLC34A2. In Xenopus oocytes expressing SLC34A2 but not in water injected oocytes phosphate (1 mM) induced a current (Ip) which was significantly enhanced by coexpression of mTOR. Preincubation of the oocytes for 24 h with rapamycin (50 nM) did not significantly affect Ip in the absence of mTOR but virtually abolished the increase of Ip following coexpression of mTOR. The wild type serum and glucocorticoid inducible kinase SGK1 and the constitutively active (S422D)SGK1 similarly stimulated Ip, an effect again reversed by rapamycin. Coexpression of the inactive mutant of the serum and glucocorticoid inducible kinase (K119N)SGK1 significantly decreased Ip and abrogated the stimulating effect of mTOR on Ip. In conclusion, mTOR and SGK1 cooperate in the stimulation of the intestinal phosphate transporter SLC34A2. PMID:16730658

  1. Preparation, characterization, biological activity, and transport study of polystyrene based calcium-barium phosphate composite membrane.

    PubMed

    Khan, Mohammad Mujahid Ali; Rafiuddin

    2013-10-01

    Calcium-barium phosphate (CBP) composite membrane with 25% polystyrene was prepared by co-precipitation method. Scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transformed infrared (FTIR), and Thermogravimetric analysis (TGA) were used to characterize the membrane. The membrane was found to be crystalline in nature with consistent arrangement of particles and no indication of visible cracks. The electrical potentials measured across the composite membrane in contact with univalent electrolytes (KCl, NaCl and LiCl), have been found to increase with decrease in concentrations. Thus the membrane was found to be cation-selective. Transport properties of developed membranes may be utilized for the efficient desalination of saline water and more importantly demineralization process. The antibacterial study of this composite membrane shows good results for killing the disease causing bacteria along with waste water treatment. PMID:23910337

  2. Spinster 2, a sphingosine-1-phosphate transporter, plays a critical role in inflammatory and autoimmune diseases.

    PubMed

    Donoviel, Michael S; Hait, Nitai C; Ramachandran, Subramaniam; Maceyka, Michael; Takabe, Kazuaki; Milstien, Sheldon; Oravecz, Tamas; Spiegel, Sarah

    2015-12-01

    Sphingosine 1-phosphate (S1P) is a pleiotropic bioactive sphingolipid metabolite that regulates numerous processes important for immune responses. S1P is made within cells and must be transported out of cells to exert its effects through activation of 5 specific cell surface GPCRs in an autocrine or paracrine fashion. Spinster 2 (Spns2) transports S1P out of cells, and its deletion in mice reduces circulating levels of S1P, alters immune cell trafficking, and induces lymphopenia. Here we examined the effects of Spns2 deletion on adaptive immune responses and in autoimmune disease models. Airway inflammation and hypersensitivity as well as delayed-type contact hypersensitivity were attenuated in Spns2(-/-) mice. Similarly, Spns2 deletion reduced dextran sodium sulfate- and oxazolone-induced colitis. Intriguingly, Spns2(-/-) mice were protected from the development of experimental autoimmune encephalopathy, a model of the autoimmune disease multiple sclerosis. Deletion of Spns2 also strongly alleviated disease development in collagen-induced arthritis. These results point to a broad role for Spns2-mediated S1P transport in the initiation and development of adaptive immune related disorders. PMID:26324848

  3. Nature-Inspired Design of Artificial Solar-to-Fuel Conversion Systems based on Copper Phosphate Microflowers.

    PubMed

    Wang, Jing; Zhu, Ting; Ho, Ghim Wei

    2016-07-01

    Phosphates play significant roles in plant photosynthesis by mediating electron transportation and furnishing energy for CO2 reduction. Motivated by this, we demonstrate herein an artificial solar-to-fuel conversion system, involving versatile copper phosphate microflowers as template and titanium dioxide nanoparticles as host photocatalyst. The elaborate flowerlike architectures, coupled with a unique proton-reduction cycle from interchangeability of different species of orthophosphate ions, not only offer a 2D nanosheet platform for an optimal heterostructure interface but also effectively augment charge-carrier transfer, thereby contributing to enhanced photoactivity and hydrogen generation. These nature-inspired, phosphate-derived nanocomposites advance the synthesis of a large variety of functional materials, which holds great potential for photochemical, photoelectric and catalytic applications. PMID:27225314

  4. Fibroblast Growth Factor-23-mediated Inhibition of Renal Phosphate Transport in Mice Requires Sodium-Hydrogen Exchanger Regulatory Factor-1 (NHERF-1) and Synergizes with Parathyroid Hormone*

    PubMed Central

    Weinman, Edward J.; Steplock, Deborah; Shenolikar, Shirish; Biswas, Rajatsubhra

    2011-01-01

    Fibroblast growth factor-23 (FGF-23) inhibits sodium-dependent phosphate transport in brush border membrane vesicles derived from hormone-treated kidney slices of the mouse and in mouse proximal tubule cells by processes involving mitogen-activated protein kinase (MAPK) but not protein kinase A (PKA) or protein kinase C (PKC). By contrast, phosphate transport in brush border membrane vesicles and proximal tubule cells from sodium-hydrogen exchanger regulatory factor-1 (NHERF-1)-null mice were resistant to the inhibitory effect of FGF-23 (10−9 m). Infection of NHERF-1-null proximal tubule cells with wild-type adenovirus-GFP-NHERF-1 increased basal phosphate transport and restored the inhibitory effect of FGF-23. Infection with adenovirus-GFP-NHERF-1 containing a S77A or T95D mutation also increased basal phosphate transport, but the cells remained resistant to FGF-23 (10−9 m). Low concentrations of FGF-23 (10−13 m) and PTH (10−11 m) individually did not inhibit phosphate transport or activate PKA, PKC, or MAPK. When combined, however, these hormones markedly inhibited phosphate transport associated with activation of PKC and PKA but not MAPK. These studies indicate that FGF-23 inhibits phosphate transport in the mouse kidney by processes that involve the scaffold protein NHERF-1. In addition, FGF-23 synergizes with PTH to inhibit phosphate transport by facilitating the activation of the PTH signal transduction pathway. PMID:21908609

  5. The role of the synergistic phosphate anion in iron transport by the periplasmic iron-binding protein from Haemophilus influenzae

    PubMed Central

    Khan, Ali G.; Shouldice, Stephen R.; Tari, Leslie W.; Schryvers, Anthony B.

    2006-01-01

    The acquisition of iron from transferrin by Gram-negative bacterial pathogens is dependent on a periplasmic ferric-ion-binding protein, FbpA. FbpA shuttles iron from the outer membrane to an inner membrane transport complex. A bound phosphate anion completes the iron co-ordination shell of FbpA and kinetic studies demonstrate that the anion plays a critical role in iron binding and release in vitro. The present study was initiated to directly address the hypothesis that the synergistic anion is required for transport of iron in intact cells. A series of site-directed mutants in the anion-binding amino acids of the Haemophilus influenzae FbpA (Gln-58, Asn-175 and Asn-193) were prepared to provide proteins defective in binding of the phosphate anion. Crystal structures of various mutants have revealed that alteration of the C-terminal domain ligands (Asn-175 or Asn-193) but not the N-terminal domain ligand (Gln-58) abrogated binding of the phosphate anion. The mutant proteins were introduced into H. influenzae to evaluate their ability to mediate iron transport. All of the single site-directed mutants (Q58L, N175L and N193L) were capable of mediating iron acquisition from transferrin and from limiting concentrations of ferric citrate. The results suggest that the transport of iron by FbpA is not dependent on binding of phosphate in the synergistic anion-binding site. PMID:17147516

  6. Nectar secretion requires sucrose phosphate synthases and the sugar transporter SWEET9.

    PubMed

    Lin, I Winnie; Sosso, Davide; Chen, Li-Qing; Gase, Klaus; Kim, Sang-Gyu; Kessler, Danny; Klinkenberg, Peter M; Gorder, Molly K; Hou, Bi-Huei; Qu, Xiao-Qing; Carter, Clay J; Baldwin, Ian T; Frommer, Wolf B

    2014-04-24

    Angiosperms developed floral nectaries that reward pollinating insects. Although nectar function and composition have been characterized, the mechanism of nectar secretion has remained unclear. Here we identify SWEET9 as a nectary-specific sugar transporter in three eudicot species: Arabidopsis thaliana, Brassica rapa (extrastaminal nectaries) and Nicotiana attenuata (gynoecial nectaries). We show that SWEET9 is essential for nectar production and can function as an efflux transporter. We also show that sucrose phosphate synthase genes, encoding key enzymes for sucrose biosynthesis, are highly expressed in nectaries and that their expression is also essential for nectar secretion. Together these data are consistent with a model in which sucrose is synthesized in the nectary parenchyma and subsequently secreted into the extracellular space via SWEET9, where sucrose is hydrolysed by an apoplasmic invertase to produce a mixture of sucrose, glucose and fructose. The recruitment of SWEET9 for sucrose export may have been a key innovation, and could have coincided with the evolution of core eudicots and contributed to the evolution of nectar secretion to reward pollinators. PMID:24670640

  7. Droplet transport system and methods

    NASA Technical Reports Server (NTRS)

    Neitzel, G. Paul (Inventor)

    2010-01-01

    Embodiments of droplet transport systems and methods are disclosed for levitating and transporting single or encapsulated droplets using thermocapillary convection. One method embodiment, among others comprises providing a droplet of a first liquid; and applying thermocapillary convection to the droplet to levitate and move the droplet.

  8. The sulfolipid sulfoquinovosyldiacylglycerol is not required for photosynthetic electron transport in Rhodobacter sphaeroides but enhances growth under phosphate limitation

    SciTech Connect

    Benning, C.; Somerville, C.R. ); Beatty, J.T. ); Prince, R.C. )

    1993-02-15

    All photosynthetic organisms, with the exception of several species of photosynthetic bacteria, are thought to contain the sulfolipid 6-sulfo-[alpha]-D-quinovosyldiacylglycerol. The association of this lipid with photosynthetic membranes has led to the assumption that it plays some role in photosynthesis. Stable null mutants of the photosynthetic bacterium Rhodobacter sphaeroides completely lacking sulfolipid were obtained by disruption of the sqdB gene. The ratios of the various components of the photosynthetic electron transport chain, as well as the electron transfer rates during cyclic electron transport, were not altered in the mutants, when grown under optimal conditions. Growth rates of wild type and mutants were identical under a variety of growth conditions, with the exception of phosphate limitation, which resulted in reduced growth of the mutants. Phosphate limitation of the wild type a used a significant reduction in the amount of all phospholipids and an increased amount of sulfolipid. By contrast, the sulfolipid-deficient mutant had reduced levels of phosphatidylcholine and phosphatidylethanolamine but maintained a normal level of phosphatidylglycerol. In addition, two unidentified lipids lacking phosphorus accumulated in the membranes of both wild-type and mutant strains under phosphate limitation. We conclude that sulfolipid plays no significant unique role in photoheterotrophic growth or photosynthetic electron transport in R. sphaeroides but may function as a surrogate for phospholipids, particularly phosphatidylglycerol, under phosphate-limiting conditions. 34 refs., 5 figs., 1 tab.

  9. Structure and expression profile of the phosphate Pht1 transporter gene family in mycorrhizal Populus trichocarpa.

    PubMed

    Loth-Pereda, Verónica; Orsini, Elena; Courty, Pierre-Emmanuel; Lota, Frédéric; Kohler, Annegret; Diss, Loic; Blaudez, Damien; Chalot, Michel; Nehls, Uwe; Bucher, Marcel; Martin, Francis

    2011-08-01

    Gene networks involved in inorganic phosphate (Pi) acquisition and homeostasis in woody perennial species able to form mycorrhizal symbioses are poorly known. Here, we describe the features of the 12 genes coding for Pi transporters of the Pht1 family in poplar (Populus trichocarpa). Individual Pht1 transporters play distinct roles in acquiring and translocating Pi in different tissues of mycorrhizal and nonmycorrhizal poplar during different growth conditions and developmental stages. Pi starvation triggered the up-regulation of most members of the Pht1 family, especially PtPT9 and PtPT11. PtPT9 and PtPT12 showed a striking up-regulation in ectomycorrhizas and endomycorrhizas, whereas PtPT1 and PtPT11 were strongly down-regulated. PtPT10 transcripts were highly abundant in arbuscular mycorrhiza (AM) roots only. PtPT8 and PtPT10 are phylogenetically associated to the AM-inducible Pht1 subfamily I. The analysis of promoter sequences revealed conserved motifs similar to other AM-inducible orthologs in PtPT10 only. To gain more insight into gene regulatory mechanisms governing the AM symbiosis in woody plant species, the activation of the poplar PtPT10 promoter was investigated and detected in AM of potato (Solanum tuberosum) roots. These results indicated that the regulation of AM-inducible Pi transporter genes is conserved between perennial woody and herbaceous plant species. Moreover, poplar has developed an alternative Pi uptake pathway distinct from AM plants, allowing ectomycorrhizal poplar to recruit PtPT9 and PtPT12 to cope with limiting Pi concentrations in forest soils. PMID:21705655

  10. Pht2;1 encodes a low-affinity phosphate transporter from Arabidopsis.

    PubMed Central

    Daram, P; Brunner, S; Rausch, C; Steiner, C; Amrhein, N; Bucher, M

    1999-01-01

    An Arabidopsis genomic sequence was recently shown to share similarity with bacterial and eukaryotic phosphate (Pi) transporters. We have cloned the corresponding cDNA, which we named Pht2;1, and subsequently performed gene expression studies and functional analysis of the protein product. The cDNA encodes a 61-kD protein with a putative topology of 12 transmembrane (TM) domains interrupted by a large hydrophilic loop between TM8 and TM9. Two boxes of eight and nine amino acids, located in the N- and C-terminal domains, respectively, are highly conserved among species across all kingdoms (eubacteria, archea, fungi, plants, and animals). The Pht2;1 gene is predominantly expressed in green tissue, the amount of transcript staying constant in leaves irrespective of the Pi status of the shoot; in roots, however, there is a marginal increase in mRNA amounts in response to Pi deprivation. Although the protein is highly similar to eukaryotic sodium-dependent Pi transporters, functional analysis of the Pht2;1 protein in mutant yeast cells indicates that it is a proton/Pi symporter dependent on the electrochemical gradient across the plasma membrane. Its fairly high apparent K(m) for Pi (0.4 mM) and high mRNA content in the shoot, especially in leaves, suggest a role for shoot organs in Pi loading. Pht2;1 thus differs from members of the recently described plant Pi transporter family in primary structure, affinity for Pi, and presumed function. PMID:10559441

  11. Phosphate reduction in a hydroxyapatite fluoride removal system

    NASA Astrophysics Data System (ADS)

    Egner, A.

    2012-12-01

    Fluorosis is a widespread disease that occurs as a result of excess fluoride consumption and can cause severe tooth and bone deformations. To combat fluorosis, several previous studies have examined the potential to replace traditional bone char filters with synthetic hydroxyapatite. Calcite particles with a synthetic hydroxyapatite coating have been shown to effectively removed fluoride, yet the low-cost method for forming these particles leaves high amounts of phosphate both in synthesis waste-water and in filter effluent. High phosphate in filter effluent is problematic because consumption of extremely high phosphate can leach calcium from bones, further exacerbating the fluoride effect. This study examines ways of reducing and reusing waste. In particular, a method of fluoride removal is explored in which fluorapatite coatings may be formed directly. In preliminary studies, batches of 4.1g of Florida limestone (<710 μm) were equilibrated with 100 mL of 10ppm fluoride. In a control batch containing lime but no added phosphate, 14% treatment was achieved, but with added phosphate, 100% treatment was achieved in all batches. Batches with lower levels of phosphate took longer to reach 100% treatment, ranging from less than 24 hours in the highest phosphate batches to approximately 42 hours in the lowest batches. The lower levels tested were well within reasonable levels for drinking water and reached 0ppm fluoride in 42 hours or less.

  12. Preliminary time-of-flight neutron diffraction studies of Escherichia coli ABC transport receptor phosphate-binding protein at the Protein Crystallography Station

    PubMed Central

    Sippel, K. H.; Bacik, J.; Quiocho, F. A.; Fisher, S. Z.

    2014-01-01

    Inorganic phosphate is an essential molecule for all known life. Organisms have developed many mechanisms to ensure an adequate supply, even in low-phosphate conditions. In prokaryotes phosphate transport is instigated by the phosphate-binding protein (PBP), the initial receptor for the ATP-binding cassette (ABC) phosphate transporter. In the crystal structure of the PBP–phosphate complex, the phosphate is completely desolvated and sequestered in a deep cleft and is bound by 13 hydrogen bonds: 12 to protein NH and OH donor groups and one to a carboxylate acceptor group. The carboxylate plays a key recognition role by accepting a phosphate hydrogen. PBP phosphate affinity is relatively consistent across a broad pH range, indicating the capacity to bind monobasic (H2PO4 −) and dibasic (HPO4 2−) phosphate; however, the mechanism by which it might accommodate the second hydrogen of monobasic phosphate is unclear. To answer this question, neutron diffraction studies were initiated. Large single crystals with a volume of 8 mm3 were grown and subjected to hydrogen/deuterium exchange. A 2.5 Å resolution data set was collected on the Protein Crystallography Station at the Los Alamos Neutron Science Center. Initial refinement of the neutron data shows significant nuclear density, and refinement is ongoing. This is the first report of a neutron study from this superfamily. PMID:24915101

  13. The Phosphate Transporter Gene OsPht1;8 Is Involved in Phosphate Homeostasis in Rice1[W][OA

    PubMed Central

    Jia, Hongfang; Ren, Hongyan; Gu, Mian; Zhao, Jianning; Sun, Shubin; Zhang, Xiao; Chen, Jieyu; Wu, Ping; Xu, Guohua

    2011-01-01

    Plant phosphate transporters (PTs) are active in the uptake of inorganic phosphate (Pi) from the soil and its translocation within the plant. Here, we report on the biological properties and physiological roles of OsPht1;8 (OsPT8), one of the PTs belonging to the Pht1 family in rice (Oryza sativa). Expression of a β-glucuronidase and green fluorescent protein reporter gene driven by the OsPT8 promoter showed that OsPT8 is expressed in various tissue organs from roots to seeds independent of Pi supply. OsPT8 was able to complement a yeast Pi-uptake mutant and increase Pi accumulation of Xenopus laevis oocytes when supplied with micromolar 33Pi concentrations at their external solution, indicating that it has a high affinity for Pi transport. Overexpression of OsPT8 resulted in excessive Pi in both roots and shoots and Pi toxic symptoms under the high-Pi supply condition. In contrast, knockdown of OsPT8 by RNA interference decreased Pi uptake and plant growth under both high- and low-Pi conditions. Moreover, OsPT8 suppression resulted in an increase of phosphorus content in the panicle axis and in a decrease of phosphorus content in unfilled grain hulls, accompanied by lower seed-setting rate. Altogether, our data suggest that OsPT8 is involved in Pi homeostasis in rice and is critical for plant growth and development. PMID:21502185

  14. Heat transport system

    DOEpatents

    Harkness, Samuel D.

    1982-01-01

    A falling bed of ceramic particles receives neutron irradiation from a neutron-producing plasma and thereby transports energy as heat from the plasma to a heat exchange location where the ceramic particles are cooled by a gas flow. The cooled ceramic particles are elevated to a location from which they may again pass by gravity through the region where they are exposed to neutron radiation. Ceramic particles of alumina, magnesia, silica and combinations of these materials are contemplated as high-temperature materials that will accept energy from neutron irradiation. Separate containers of material incorporating lithium are exposed to the neutron flux for the breeding of tritium that may subsequently be used in neutron-producing reactions. The falling bed of ceramic particles includes velocity partitioning between compartments near to the neutron-producing plasma and compartments away from the plasma to moderate the maximum temperature in the bed.

  15. Heat transport system

    DOEpatents

    Harkness, S.D.

    A falling bed of ceramic particles receives neutron irradiation from a neutron-producing plasma and thereby transports energy as heat from the plasma to a heat exchange location where the ceramic particles are cooled by a gas flow. The cooled ceramic particles are elevated to a location from which they may again pass by gravity through the region where they are exposed to neutron radiation. Ceramic particles of alumina, magnesia, silica and combinations of these materials are contemplated as high-temperature materials that will accept energy from neutron irradiation. Separate containers of material incorporating lithium are exposed to the neutron flux for the breeding of tritium that may subsequently be used in neutron-producing reactions. The falling bed of ceramic particles includes velocity partitioning between compartments near to the neutron-producing plasma and compartments away from the plasma to moderate the maximum temperature in the bed.

  16. Advanced Transport Operating Systems Program

    NASA Technical Reports Server (NTRS)

    White, John J.

    1990-01-01

    NASA-Langley's Advanced Transport Operating Systems Program employs a heavily instrumented, B 737-100 as its Transport Systems Research Vehicle (TRSV). The TRSV has been used during the demonstration trials of the Time Reference Scanning Beam Microwave Landing System (TRSB MLS), the '4D flight-management' concept, ATC data links, and airborne windshear sensors. The credibility obtainable from successful flight test experiments is often a critical factor in the granting of substantial commitments for commercial implementation by the FAA and industry. In the case of the TRSB MLS, flight test demonstrations were decisive to its selection as the standard landing system by the ICAO.

  17. Overexpression of Mitochondrial Phosphate Transporter 3 Severely Hampers Plant Development through Regulating Mitochondrial Function in Arabidopsis

    PubMed Central

    Jia, Fengjuan; Wan, Xiaomin; Zhu, Wei; Sun, Dan; Zheng, Chengchao; Liu, Pei; Huang, Jinguang

    2015-01-01

    Mitochondria are abundant and important organelles present in nearly all eukaryotic cells, which maintain metabolic communication with the cytosol through mitochondrial carriers. The mitochondrial membrane localized phosphate transporter (MPT) plays vital roles in diverse development and signaling processes, especially the ATP biosynthesis. Among the three MPT genes in Arabidopsis genome, AtMPT3 was proven to be a major member, and its overexpression gave rise to multiple developmental defects including curly leaves with deep color, dwarfed stature, and reduced fertility. Transcript profiles revealed that genes involved in plant metabolism, cellular redox homeostasis, alternative respiration pathway, and leaf and flower development were obviously altered in AtMPT3 overexpression (OEMPT3) plants. Moreover, OEMPT3 plants also accumulated higher ATP content, faster respiration rate and more reactive oxygen species (ROS) than wild type plants. Overall, our studies showed that AtMPT3 was indispensable for Arabidopsis normal growth and development, and provided new sights to investigate its possible regulation mechanisms. PMID:26076137

  18. Structure-Independent Proton Transport in Cerium(III) Phosphate Nanowires.

    PubMed

    Pusztai, Péter; Haspel, Henrik; Tóth, Ildikó Y; Tombácz, Etelka; László, Krisztina; Kukovecz, Ákos; Kónya, Zoltán

    2015-05-13

    Understanding of water-related electrical conduction is of utmost importance in applications that utilize solid-state proton conductors. However, in spite of the vast amount of theoretical and experimental work published in the literature, thus far its mechanism remained unsolved. In this study, the structure-related ambient temperature electrical conduction of one-dimensional hydrophilic nanostructures was investigated. Cerium phosphate nanowires with monoclinic and hexagonal crystal structures were synthesized via the hydrothermal and ambient temperature precipitation routes, and their structural and surface properties were examined by using high-resolution transmission electron microscopy, X-ray diffractometry, nitrogen and water sorption, temperature-programmed ammonia desorption, and potentiometric titration techniques. The relative humidity (RH)-dependent charge-transport processes of hexagonal and monoclinic nanowires were investigated by means of impedance spectroscopy and transient ionic current measurement techniques to gain insight into their atomistic level mechanism. Although considerable differences in RH-dependent conductivity were first found, the distinct characteristics collapsed into a master curve when specific surface area and acidity were taken into account, implying structure-independent proton conduction mechanism in both types of nanowires. PMID:25859883

  19. Influence of lithium vacancies on the polaronic transport in olivine phosphate structure

    NASA Astrophysics Data System (ADS)

    Murugavel, Sevi; Sharma, Monika; Shahid, Raza

    2016-01-01

    Intercalation and deintercalation of lithium ions in cathode materials are of principal to the operation of current rechargeable lithium ion batteries. The performance of lithium ion batteries highly relies on the active cathode material which includes cell potential, power/energy density, capacity, etc. An important issue in this class of material is to resolve the factors governing the electron and ion transport in olivine phosphate structure. In this class of material, there is still an open debate on the mechanism of charge transport including both polarons and lithium ions. On the one hand, this is due to the large disparity between the experimental results and the theoretical model predictions. On the other hand, this is also due to the lack of precise experimental measurement without any parasitic phases in a given cathode material. Here, we present the polaronic conduction in lithiated triphylite LiFePO4 (LFP) and delithiated heterosite FePO4 (FP) by means of broadband ac impedance spectroscopy over wide range temperatures and frequency. It is found that the LFP phase possess two orders of higher polaronic conductivity than FP phase despite having similar mobility of polarons in both phases. We show that the differences in the polaronic conductivity of two phases are due to the significant differences in concentration of polarons. It is found that the formation energy of polarons in individual phases is mainly determined by the corresponding defect state associated with it. The temperature dependent dc conductivity has been analyzed within the framework of Mott model of polaronic conduction and explored the origin of polaronic conduction mechanism in this class of material.

  20. Rice SPX-Major Facility Superfamily3, a Vacuolar Phosphate Efflux Transporter, Is Involved in Maintaining Phosphate Homeostasis in Rice1[OPEN

    PubMed Central

    Ying, Yinghui; Wang, Shoudong; Secco, David; Liu, Yu; Whelan, James; Tyerman, Stephen D.; Shou, Huixia

    2015-01-01

    To maintain a stable cytosol phosphate (Pi) concentration, plant cells store Pi in their vacuoles. When the Pi concentration in the cytosol decreases, Pi is exported from the vacuole into the cytosol. This export is mediated by Pi transporters on the tonoplast. In this study, we demonstrate that SYG1, PHO81, and XPR1 (SPX)-Major Facility Superfamily (MFS) proteins have a similar structure with yeast (Saccharomyces cerevisiae) low-affinity Pi transporters Phosphatase87 (PHO87), PHO90, and PHO91. OsSPX-MFS1, OsSPX-MFS2, and OsSPX-MFS3 all localized on the tonoplast of rice (Oryza sativa) protoplasts, even in the absence of the SPX domain. At high external Pi concentration, OsSPX-MFS3 could partially complement the yeast mutant strain EY917 under pH 5.5, which lacks all five Pi transporters present in yeast. In oocytes, OsSPX-MFS3 was shown to facilitate Pi influx or efflux depending on the external pH and Pi concentrations. In contrast to tonoplast localization in plants cells, OsSPX-MFS3 was localized to the plasma membrane when expressed in both yeast and oocytes. Overexpression of OsSPX-MFS3 results in decreased Pi concentration in the vacuole of rice tissues. We conclude that OsSPX-MFS3 is a low-affinity Pi transporter that mediates Pi efflux from the vacuole into cytosol and is coupled to proton movement. PMID:26424157

  1. Tether Transportation System Study

    NASA Technical Reports Server (NTRS)

    Bangham, M. E.; Lorenzini, E.; Vestal, L.

    1998-01-01

    The projected traffic to geostationary earth orbit (GEO) is expected to increase over the next few decades. At the same time, the cost of delivering payloads from the Earth's surface to low earth orbit (LEO) is projected to decrease, thanks in part to the Reusable Launch Vehicle (RLV). A comparable reduction in the cost of delivering payloads from LEO to GEO is sought. The use of in-space tethers, eliminating the requirement for traditional chemical upper stages and thereby reducing the launch mass, has been identified as such an alternative. Spinning tethers are excellent kinetic energy storage devices for providing the large delta vee's required for LEO to GEO transfer. A single-stage system for transferring payloads from LEO to GEO was proposed some years ago. The study results presented here contain the first detailed analyses of this proposal, its extension to a two-stage system, and the likely implementation of the operational system.

  2. The competitive advantage of a dual-transporter system.

    PubMed

    Levy, Sagi; Kafri, Moshe; Carmi, Miri; Barkai, Naama

    2011-12-01

    Cells use transporters of different affinities to regulate nutrient influx. When nutrients are depleted, low-affinity transporters are replaced by high-affinity ones. High-affinity transporters are helpful when concentrations of nutrients are low, but the advantage of reducing their abundance when nutrients are abundant is less clear. When we eliminated such reduced production of the Saccharomyces cerevisiae high-affinity transporters for phosphate and zinc, the elapsed time from the initiation of the starvation program until the lack of nutrients limited growth was shortened, and recovery from starvation was delayed. The latter phenotype was rescued by constitutive activation of the starvation program. Dual-transporter systems appear to prolong preparation for starvation and to facilitate subsequent recovery, which may optimize sensing of nutrient depletion by integrating internal and external information about nutrient availability. PMID:22158820

  3. Transport Systems in Halophilic Fungi.

    PubMed

    Plemenitaš, Ana; Konte, Tilen; Gostinčar, Cene; Cimerman, Nina Gunde

    2016-01-01

    Fungi that tolerate very high environmental NaCl concentrations are good model systems to study mechanisms that enable them to endure osmotic and salinity stress. The whole genome sequences of six such fungal species have been analysed: Hortaea werneckii, Wallemia ichthyophaga and four Aureobasidium spp.: A. pullulans, A. subglaciale, A. melanogenum and A. namibiae. These fungi show different levels of halotolerance, with the presence of numerous membrane transport systems uncovered here that are believed to maintain physiological intracellular concentrations of alkali metal cations. Despite some differences, the intracellular cation contents of H. werneckii, A. pullulans and W. ichthyophaga remain low even under extreme extracellular salinities, which suggests that these species have efficient cation transport systems. We speculate that cation transporters prevent intracellular accumulation of Na(+), and thus avoid the toxic effects that such Na(+) accumulation would have, while also maintaining the high K(+)/Na(+) ratio that is required for the full functioning of the cell - another crucial task in high-Na(+) environments. This chapter primarily summarises the cation transport systems of these selected fungi, and it also describes other membrane transporters that might be involved in their mechanisms of halotolerance. PMID:26721280

  4. Contribution of TAT System Translocated PhoX to Campylobacter jejuni Phosphate Metabolism and Resilience to Environmental Stresses

    PubMed Central

    Drozd, Mary; Gangaiah, Dharanesh; Liu, Zhe; Rajashekara, Gireesh

    2011-01-01

    Campylobacter jejuni is a common gastrointestinal pathogen that colonizes food animals; it is transmitted via fecal contamination of food, and infections in immune-compromised people are more likely to result in serious long-term illness. Environmental phosphate is likely an important sensor of environmental fitness and the ability to obtain extracellular phosphate is central to the bacteria's core metabolic responses. PhoX is the sole alkaline phosphatase in C. jejuni, a substrate of the TAT transport system. Alkaline phosphatases mediate the hydrolytic removal of inorganic phosphate (Pi) from phospho-organic compounds and thereby contribute significantly to the polyphosphate kinase 1 (ppk1) mediated formation of poly P, a molecule that regulates bacterial response to stresses and virulence. Similarly, deletion of the tatC gene, a key component of the TAT system, results in diverse phenotypes in C. jejuni including reduced stress tolerance and in vivo colonization. Therefore, here we investigated the contribution of phoX in poly P synthesis and in TAT-system mediated responses. The phoX deletion mutant showed significant decrease (P<0.05) in poly P accumulation in stationary phase compared to the wild-type, suggesting that PhoX is a major contributor to the inorganic phosphate pool in the cell which is essential for poly P synthesis. The phoX deletion is sufficient for a nutrient stress defect similar to the defect previously described for the ΔtatC mutant. Additionally, the phoX deletion mutant has increased resistance to certain antimicrobials. The ΔphoX mutant was also moderately defective in invasion and intracellular survival within human intestinal epithelial cells as well as in chicken colonization. Further, the ΔphoX mutant produced increased biofilm that can be rescued with 1 mM inorganic phosphate. The qRT-PCR of the ΔphoX mutant revealed transcriptional changes that suggest potential mechanisms for the increased biofilm phenotype. PMID:22028859

  5. Earthquake damage to transportation systems

    USGS Publications Warehouse

    McCullough, Heather

    1994-01-01

    Earthquakes represent one of the most destructive natural hazards known to man. A large magnitude earthquake near a populated area can affect residents over thousands of square kilometers and cause billions of dollars in property damage. Such an event can kill or injure thousands of residents and disrupt the socioeconomic environment for months, sometimes years. A serious result of a large-magnitude earthquake is the disruption of transportation systems, which limits post-disaster emergency response. Movement of emergency vehicles, such as police cars, fire trucks and ambulances, is often severely restricted. Damage to transportation systems is categorized below by cause including: ground failure, faulting, vibration damage, and tsunamis.

  6. Surveillance systems for intermodal transportation

    NASA Astrophysics Data System (ADS)

    Jakovlev, Sergej; Voznak, Miroslav; Andziulis, Arunas

    2015-05-01

    Intermodal container monitoring is considered a major security issue in many major logistic companies and countries worldwide. Current representation of the problem, we face today, originated in 2002, right after the 9/11 attacks. Then, a new worldwide Container Security Initiative (CSI, 2002) was considered that shaped the perception of the transportation operations. Now more than 80 larger ports all over the world contribute to its further development and integration into everyday transportation operations and improve the regulations for the developing regions. Although, these new improvements allow us to feel safer and secure, constant management of transportation operations has become a very difficult problem for conventional data analysis methods and information systems. The paper deals with a proposal of a whole new concept for the improvement of the Containers Security Initiative (CSI) by virtually connecting safety, security processes and systems. A conceptual middleware approach with deployable intelligent agent modules is proposed to be used with possible scenarios and a testbed is used to test the solution. Middleware examples are visually programmed using National Instruments LabView software packages and Wireless sensor network hardware modules. An experimental software is used to evaluate he solution. This research is a contribution to the intermodal transportation and is intended to be used as a means or the development of intelligent transport systems.

  7. Voltage gating and anions, especially phosphate: a model system.

    PubMed

    Pradhan, Padmanava; Ghose, Ranajeet; Green, Michael E

    2005-11-30

    The voltage sensor of voltage gated sodium and potassium channels consists of four sets of transmembrane segments, of which one, called S4, contains at least four arginines; these are presumed to each carry positive charges. The channel opening is usually attributed to the outward (i.e., toward the extracellular side of the membrane) motion of S4. The evidence for this motion is based on certain experiments that appear to show differential access to parts of S4 from the intracellular and extracellular sides of the membrane in the open and closed states. A newly available structure [S.B. Long, E.B. Campbell and R. MacKinnon, Crystal structure of a mammalian voltage-dependent Shaker family K(+) channel. Science 309 (2005) 897-903; S.B. Long, E.B. Campbell, R. MacKinnon, Voltage sensor of Kv1.2: structural basis of electromechanical coupling. Science 309 (2005) 903-908][1,2] has now been used to argue for a large scale motion, although, as a static structure, it is not conclusive. In this paper, we consider the effect of anions in the surrounding medium. Phosphate is present in the intracellular as well as the extracellular fluid, apparently at hundreds of micromolar concentration, or more. There is evidence in the literature suggesting that phosphate-arginine complexes are rather strong. In a recent calculation one of us [M.E. Green, A possible role for phosphate in complexing the arginines of S4 in voltage gated channels J. Theor. Biol. 233 (2005) 337-341][3] has shown that a model peptide with a 2:1 arg:phosphate complex should have a favorable geometry. Here, we present NMR evidence of the existence of phosphate complexes of a model peptide with two arginines separated by two hydrophobic residues, the same spacing as in S4 segments. The complexes (there are different complexes for HPO(4)(2-) and for H(2)PO(4)(-) [3]) form with concentrations of peptide in the range of hundreds of micromolar, making it significant in the biological context. NMR spectra provide

  8. Flow injection potentiometric system for the simultaneous determination of inositol phosphates and phosphate: phosphorus nutritional evaluation on seeds and grains.

    PubMed

    Parra, Aleix; Ramon, Meritxell; Alonso, Julián; Lemos, Sherlan G; Vieira, Edivan C; Nogueira, Ana R A

    2005-10-01

    A simple flow injection potentiometric (FIP) system, which uses a tubular cobalt electrode, has been developed for phosphorus nutritional evaluation of seeds and grains. Inorganic phosphorus, P(i), is determined using a 1 x 10(-2) mol.L(-1) potassium phthalate buffer solution adjusted at pH 4. A sensitivity of 47 mV/decade and an operating range from 10 to 1000 mg.L(-1) (1 x 10(-4)-1 x 10(-2) M) of dihydrogen phosphate are obtained. The inositol phosphates amount, which is referred to the organic phosphorus, P(org), is directly determined from extracts using a 1 x 10(-2) mol.L(-1) Tris-HCl buffer solution adjusted at pH 8. A sensitivity of 127 mV/decade and an operating range of 10-1000 mg.L(-1) (2.5 x 10(-4)-5 x 10(-3) M) of P(org) (expressed as inositol hexakisphosphoric acid monocalcium) are achieved. Some samples of seed and grain are analyzed by an ICP-OES and a spectrophotometric method to compare results to the developed flow system; no significant differences at the 95% confidence level are observed using a paired t test. Other samples such as animal nursing feed, soybean meal, and corn are also analyzed with the proposed FIP system, showing a good correlation to the ICP-OES values. PMID:16190610

  9. Optimal concentrations in transport systems

    PubMed Central

    Jensen, Kaare H.; Kim, Wonjung; Holbrook, N. Michele; Bush, John W. M.

    2013-01-01

    Many biological and man-made systems rely on transport systems for the distribution of material, for example matter and energy. Material transfer in these systems is determined by the flow rate and the concentration of material. While the most concentrated solutions offer the greatest potential in terms of material transfer, impedance typically increases with concentration, thus making them the most difficult to transport. We develop a general framework for describing systems for which impedance increases with concentration, and consider material flow in four different natural systems: blood flow in vertebrates, sugar transport in vascular plants and two modes of nectar drinking in birds and insects. The model provides a simple method for determining the optimum concentration copt in these systems. The model further suggests that the impedance at the optimum concentration μopt may be expressed in terms of the impedance of the pure (c = 0) carrier medium μ0 as μopt∼2αμ0, where the power α is prescribed by the specific flow constraints, for example constant pressure for blood flow (α = 1) or constant work rate for certain nectar-drinking insects (α = 6). Comparing the model predictions with experimental data from more than 100 animal and plant species, we find that the simple model rationalizes the observed concentrations and impedances. The model provides a universal framework for studying flows impeded by concentration, and yields insight into optimization in engineered systems, such as traffic flow. PMID:23594815

  10. The regulation of arbuscular mycorrhizal symbiosis by phosphate in pea involves early and systemic signalling events

    PubMed Central

    Balzergue, Coline; Puech-Pagès, Virginie; Bécard, Guillaume; Rochange, Soizic F.

    2011-01-01

    Most plants form root symbioses with arbuscular mycorrhizal (AM) fungi, which provide them with phosphate and other nutrients. High soil phosphate levels are known to affect AM symbiosis negatively, but the underlying mechanisms are not understood. This report describes experimental conditions which triggered a novel mycorrhizal phenotype under high phosphate supply: the interaction between pea and two different AM fungi was almost completely abolished at a very early stage, prior to the formation of hyphopodia. As demonstrated by split-root experiments, down-regulation of AM symbiosis occurred at least partly in response to plant-derived signals. Early signalling events were examined with a focus on strigolactones, compounds which stimulate pre-symbiotic fungal growth and metabolism. Strigolactones were also recently identified as novel plant hormones contributing to the control of shoot branching. Root exudates of plants grown under high phosphate lost their ability to stimulate AM fungi and lacked strigolactones. In addition, a systemic down-regulation of strigolactone release by high phosphate supply was demonstrated using split-root systems. Nevertheless, supplementation with exogenous strigolactones failed to restore root colonization under high phosphate. This observation does not exclude a contribution of strigolactones to the regulation of AM symbiosis by phosphate, but indicates that they are not the only factor involved. Together, the results suggest the existence of additional early signals that may control the differentiation of hyphopodia. PMID:21045005

  11. Exome Sequencing Identifies a Novel Homozygous Mutation in the Phosphate Transporter SLC34A1 in Hypophosphatemia and Nephrocalcinosis

    PubMed Central

    Rajagopal, Abbhirami; Braslavsky, Débora; Lu, James T.; Kleppe, Soledad; Clément, Florencia; Cassinelli, Hamilton; Liu, David S.; Liern, Jose Miguel; Vallejo, Graciela; Bergadá, Ignacio; Gibbs, Richard A.; Campeau, Phillipe M.

    2014-01-01

    Context: Two Argentinean siblings (a boy and a girl) from a nonconsanguineous family presented with hypercalcemia, hypercalciuria, hypophosphatemia, low parathyroid hormone (PTH), and nephrocalcinosis. Objective: The goal of this study was to identify genetic causes of the clinical findings in the two siblings. Design: Whole exome sequencing was performed to identify disease-causing mutations in the youngest sibling, and a candidate variant was screened in other family members by Sanger sequencing. In vitro experiments were conducted to determine the effects of the mutation that was identified. Patients and Other Participants: Affected siblings (2 y.o. female and 10 y.o male) and their parents were included in the study. Informed consent was obtained for genetic studies. Results: A novel homozygous mutation in the gene encoding the renal sodium-dependent phosphate transporter SLC34A1 was identified in both siblings (c.1484G>A, p.Arg495His). In vitro studies showed that the p.Arg495His mutation resulted in decreased phosphate uptake when compared to wild-type SLC34A1. Conclusions: The homozygous G>A transition that results in the substitution of histidine for arginine at position 495 of the renal sodium-dependent phosphate transporter, SLC34A1, is involved in disease pathogenesis in these patients. Our report of the second family with two mutated SLC34A1 alleles expands the known phenotype of this rare condition. PMID:25050900

  12. Transportation Cluster Volume 7 [Transportation Systems].

    ERIC Educational Resources Information Center

    Pennsylvania State Dept. of Justice, Harrisburg. Bureau of Correction.

    The document is one of seven volumes of instructional materials developed around a cluster of Transportation Industries. Primarily technical in focus, they are designed to be used in a cluster-concept program and to integrate with a regular General Education Development (G.E.D.) program so that students may attain an employable skill level and a…

  13. Lunar articulated remote transportation system

    NASA Technical Reports Server (NTRS)

    Beech, Geoffrey; Conley, Gerald; Diaz, Claudine; Dimella, Timothy; Dodson, Pete; Hykin, Jeff; Richards, Byron; Richardson, Kroy; Shetzer, Christie; Vandyke, Melissa

    1990-01-01

    A first generation lunar transportation vehicle was designed for use on the surface of the Moon between the years 2010 and 2020. Attention is focussed on specific design details on all components of the Lunar Articulated Remote Transportation System (Lunar ARTS). The Lunar ARTS will be a three cart, six-wheeled articulated vehicle. It's purpose will be for the transportation of astronauts and/or materials for excavation purposes at a short distance from the base (37.5 kilometers). The power system includes fuel cells for both the primary system and the back-up system. The vehicle has the option of being operated in a manned or unmanned mode. The unmanned mode includes stereo imaging with signal processing for navigation. For manned missions the display console is a digital readout displayed on the inside of the asronaut's helmet. A microprocessor is also on board the vehicle. Other components of the vehicle include: a double wishbone/flexible hemispherical wheel suspension; chassis; a steering system; motors; seat restraints, heat rejection systems; solar flare protection; dust protection; and meteoroid protection. A one-quarter scale dynamic model was built to study the dynamic behavior of the vehicle. The dynamic model closely captures the mechanical and electrical details of the total design.

  14. Lunar articulated remote transportation system

    NASA Technical Reports Server (NTRS)

    1990-01-01

    The students of the Florida A&M/Florida State University College of Engineering continued their design from 1988 to 1989 on a first generation lunar transportation vehicle for use on the surface of the Moon between the years 2010 and 2020. Attention is focused on specific design details on all components of the Lunar Articulated Remote Transportation System (Lunar ARTS). The Lunar ARTS will be a three-cart, six-wheeled articulated vehicle. Its purpose will be the transportation of astronauts and/or materials for excavation purposes at a short distance from the base (37.5 km). The power system includes fuel cells for both the primary system and the back-up system. The vehicle has the option of being operated in a manned or unmanned mode. The unmanned mode includes stereo imaging with signal processing for navigation. For manned missions the display console is a digital readout displayed on the inside of the astronaut's helmet. A microprocessor is also on board the vehicle. Other components of the vehicle include a double wishbone/flexible hemispherical wheel suspension; chassis; a steering system; motors; seat retraints; heat rejection systems; solar flare protection; dust protection; and meteoroid protection. A one-quarter scale dynamic model has been built to study the dynamic behavior of the vehicle. The dynamic model closely captures the mechanical and electrical details of the total design.

  15. Integrated Intermodal Passenger Transportation System

    NASA Technical Reports Server (NTRS)

    Klock, Ryan; Owens, David; Schwartz, Henry; Plencner, Robert

    2012-01-01

    Modern transportation consists of many unique modes of travel. Each of these modes and their respective industries has evolved independently over time, forming a largely incoherent and inefficient overall transportation system. Travelers today are forced to spend unnecessary time and efforts planning a trip through varying modes of travel each with their own scheduling, pricing, and services; causing many travelers to simply rely on their relatively inefficient and expensive personal automobile. This paper presents a demonstration program system to not only collect and format many different sources of trip planning information, but also combine these independent modes of travel in order to form optimal routes and itineraries of travel. The results of this system show a mean decrease in inter-city travel time of 10 percent and a 25 percent reduction in carbon dioxide emissions over personal automobiles. Additionally, a 55 percent reduction in carbon dioxide emissions is observed for intra-city travel. A conclusion is that current resources are available, if somewhat hidden, to drastically improve point to point transportation in terms of time spent traveling, the cost of travel, and the ecological impact of a trip. Finally, future concepts are considered which could dramatically improve the interoperability and efficiency of the transportation infrastructure.

  16. Complex Regulation of Plant Phosphate Transporters and the Gap between Molecular Mechanisms and Practical Application: What Is Missing?

    PubMed

    Gu, Mian; Chen, Aiqun; Sun, Shubin; Xu, Guohua

    2016-03-01

    It has been almost 25 years since the first report of the gene encoding a high-affinity phosphate transporter (PT), PHO84, in yeast. Since then, an increasing number of yeast PHO84 homologs as well as other genes encoding proteins with phosphate (Pi) transport activities have been identified and functionally characterized in diverse plant species. Great progress has been made also in deciphering the molecular mechanism underlying the regulation of the abundance and/or activity of these genes and their products. The regulatory genes affect plant Pi homeostasis commonly through direct or indirect regulation of the abundance of PTs at different levels. However, little has been achieved in the use of PTs for developing genetically modified crops with high phosphorus use efficiency (PUE). This might be a consequence of overemphasizing Pi uptake from the rhizosphere and lack of knowledge about the roles of PTs in Pi transport and recycling within the plant that are required to optimize PUE. Here, we mainly focused on the genes encoding proteins with Pi transport activities and the emerging understanding of their regulation at the transcriptional, post-transcriptional, translational, and post-translational levels. In addition, we propose potential strategies for effective use of PTs in improving plant growth and development. PMID:26714050

  17. Conditional Deletion of Fgfr1 in the Proximal and Distal Tubule Identifies Distinct Roles in Phosphate and Calcium Transport

    PubMed Central

    Han, Xiaobin; Yang, Jiancheng; Li, Linqiang; Huang, Jinsong; King, Gwendalyn; Quarles, L. Darryl

    2016-01-01

    A postnatal role of fibroblast growth factor receptor-1 (FGFR1) in the kidney is suggested by its binding to α-Klotho to form an obligate receptor for the hormone fibroblast growth factor-23 (FGF-23). FGFR1 is expressed in both the proximal and distal renal tubular segments, but its tubular specific functions are unclear. In this study, we crossed Fgfr1flox/flox mice with either gamma-glutamyltransferase-Cre (γGT-Cre) or kidney specific-Cre (Ksp-Cre) mice to selectively create proximal tubule (PT) and distal tubule (DT) Fgfr1 conditional knockout mice (designated Fgfr1PT-cKO and Fgfr1DT-cKO, respectively). Fgfr1PT-cKO mice exhibited an increase in sodium-dependent phosphate co-transporter expression, hyperphosphatemia, and refractoriness to the phosphaturic actions of FGF-23, consistent with a direct role of FGFR1 in mediating the proximal tubular phosphate responses to FGF-23. In contrast, Fgfr1DT-cKO mice unexpectedly developed hypercalciuria, secondary elevations of parathyroid hormone (PTH), hypophosphatemia and enhanced urinary phosphate excretion. Fgfr1PT-cKO mice also developed a curly tail/spina bifida-like skeletal phenotype, whereas Fgfr1DT-cKO mice developed renal tubular micro-calcifications and reductions in cortical bone thickness. Thus, FGFR1 has dual functions to directly regulate proximal and distal tubule phosphate and calcium reabsorption, indicating a physiological role of FGFR1 signaling in both phosphate and calcium homeostasis. PMID:26839958

  18. Oxygen isotopes as a tracer of phosphate sources and cycling in aquatic systems (Invited)

    NASA Astrophysics Data System (ADS)

    Young, M. B.; Kendall, C.; Paytan, A.

    2013-12-01

    The oxygen isotopic composition of phosphate can provide valuable information about sources and processes affecting phosphorus as it moves through hydrologic systems. Applications of this technique in soil and water have become more common in recent years due to improvements in extraction methods and instrument capabilities, and studies in multiple aquatic environments have demonstrated that some phosphorus sources may have distinct isotopic compositions within a given system. Under normal environmental conditions, the oxygen-phosphorus bonds in dissolved inorganic phosphate (DIP) can only be broken by enzymatic activity. Biological cycling of DIP will bring the phosphate oxygen into a temperature-dependent equilibrium with the surrounding water, overprinting any existing isotopic source signals. However, studies conducted in a wide range of estuarine, freshwater, and groundwater systems have found that the phosphate oxygen is often out of biological equilibrium with the water, suggesting that it is common for at least a partial isotopic source signal to be retained in aquatic systems. Oxygen isotope analysis on various potential phosphate sources such as synthetic and organic fertilizers, animal waste, detergents, and septic/wastewater treatment plant effluents show that these sources span a wide range of isotopic compositions, and although there is considerable overlap between the source groups, sources may be isotopically distinct within a given study area. Recent soil studies have shown that isotopic analysis of phosphate oxygen is also useful for understanding microbial cycling across different phosphorus pools, and may provide insights into controls on phosphorus leaching. Combining stable isotope information from soil and water studies will greatly improve our understanding of complex phosphate cycling, and the increasing use of this isotopic technique across different environments will provide new information regarding anthropogenic phosphate inputs and

  19. Suppression of Arbuscule Degeneration in Medicago truncatula phosphate transporter4 Mutants Is Dependent on the Ammonium Transporter 2 Family Protein AMT2;3

    PubMed Central

    Breuillin-Sessoms, Florence; Floss, Daniela S.; Gomez, S. Karen; Pumplin, Nathan; Ding, Yi; Levesque-Tremblay, Veronique; Noar, Roslyn D.; Daniels, Dierdra A.; Bravo, Armando; Eaglesham, James B.; Benedito, Vagner A.; Udvardi, Michael K.; Harrison, Maria J.

    2015-01-01

    During arbuscular mycorrhizal (AM) symbiosis, the plant gains access to phosphate (Pi) and nitrogen delivered by its fungal symbiont. Transfer of mineral nutrients occurs at the interface between branched hyphae called arbuscules and root cortical cells. In Medicago truncatula, a Pi transporter, PT4, is required for symbiotic Pi transport, and in pt4, symbiotic Pi transport fails, arbuscules degenerate prematurely, and the symbiosis is not maintained. Premature arbuscule degeneration (PAD) is suppressed when pt4 mutants are nitrogen-deprived, possibly the result of compensation by PT8, a second AM-induced Pi transporter. However, PAD is also suppressed in nitrogen-starved pt4 pt8 double mutants, negating this hypothesis and furthermore indicating that in this condition, neither of these symbiotic Pi transporters is required for symbiosis. In M. truncatula, three AMT2 family ammonium transporters are induced during AM symbiosis. To test the hypothesis that suppression of PAD involves AMT2 transporters, we analyzed double and triple Pi and ammonium transporter mutants. ATM2;3 but not AMT2;4 was required for suppression of PAD in pt4, while AMT2;4, but not AMT2;3, complemented growth of a yeast ammonium transporter mutant. In summary, arbuscule life span is influenced by PT4 and ATM2;3, and their relative importance varies with the nitrogen status of the plant. PMID:25841038

  20. Suppression of Arbuscule Degeneration in Medicago truncatula phosphate transporter4 Mutants is Dependent on the Ammonium Transporter 2 Family Protein AMT2;3.

    PubMed

    Breuillin-Sessoms, Florence; Floss, Daniela S; Gomez, S Karen; Pumplin, Nathan; Ding, Yi; Levesque-Tremblay, Veronique; Noar, Roslyn D; Daniels, Dierdra A; Bravo, Armando; Eaglesham, James B; Benedito, Vagner A; Udvardi, Michael K; Harrison, Maria J

    2015-04-01

    During arbuscular mycorrhizal (AM) symbiosis, the plant gains access to phosphate (Pi) and nitrogen delivered by its fungal symbiont. Transfer of mineral nutrients occurs at the interface between branched hyphae called arbuscules and root cortical cells. In Medicago truncatula, a Pi transporter, PT4, is required for symbiotic Pi transport, and in pt4, symbiotic Pi transport fails, arbuscules degenerate prematurely, and the symbiosis is not maintained. Premature arbuscule degeneration (PAD) is suppressed when pt4 mutants are nitrogen-deprived, possibly the result of compensation by PT8, a second AM-induced Pi transporter. However, PAD is also suppressed in nitrogen-starved pt4 pt8 double mutants, negating this hypothesis and furthermore indicating that in this condition, neither of these symbiotic Pi transporters is required for symbiosis. In M. truncatula, three AMT2 family ammonium transporters are induced during AM symbiosis. To test the hypothesis that suppression of PAD involves AMT2 transporters, we analyzed double and triple Pi and ammonium transporter mutants. ATM2;3 but not AMT2;4 was required for suppression of PAD in pt4, while AMT2;4, but not AMT2;3, complemented growth of a yeast ammonium transporter mutant. In summary, arbuscule life span is influenced by PT4 and ATM2;3, and their relative importance varies with the nitrogen status of the plant. PMID:25841038

  1. Stimulatory effect of 1,25-dihydroxycholecalciferol-like substances from Solanum malacoxylon and Cestrum diurnum on phosphate transport in chick jejunum.

    PubMed

    Peterlik, M; Wasserman, R H

    1978-10-01

    Extracts of the calcinogenic plants Solanum malocoxylon and Cestrum diurnum stimulate phosphate absorption by the jejunum of vitamin D-deficient chicks, as determined by everted gut sac technique. Their action on cellular pathways of transepithelial phosphate transport is indistinguishable thereby from that of cholecalciferol. Increased net absorption from the lumen was due to enhanced uptake of phosphate from the luminal side, while leakage of tissue phosphate in the opposite direction was apparently unaffected. Steep serosa/mucosa concentration gradients were observed as consequence of enhanced levels of transepithelial phosphate flux in the mucosa-to-serosa direction. With respect to their stimulatory action on phosphate absorption, the calcinogenic plant factors retained their biological activity when phosphate transport was depressed by a high strontium diet. Their action in overcoming the strontium inhibition of phosphate absorption, calcium-binding protein synthesis, and alkaline phosphatase activity, was comparable to the effect of 1,25-dihydroxycholecalciferol. On the basis of these biological responses, the action of the plant factors from Solanum malacoxylon and Cestrum diurnum provides further evidence for their close resemblance to the hormonally active sterol. PMID:702209

  2. PHYSICAL AND POTENTIOMETRIC CONSTANT OF FERROUS AND FERRIC PHYTATE APPLIED TO ORGANIC PHOSPHATE TRANSPORT IN POORLY DRAINED SOIL

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Inositol phosphates are metabolically derived organic phosphates that increasingly appear to be an important sink and source of phosphate in the environment. Inositol hexakis dihydrogen phosphate or phytic acid is the most common inositol phosphate in the environment. Iron is abundant in many terr...

  3. Transportable Collective Protection System (TCPS)

    SciTech Connect

    Tekesky, R.

    1990-08-15

    Human System Division (HSD/YAGD), Wright-Patterson AFB OH 45433-6503 requested assistance from the Air Force Packaging Evaluation Activity (AFPEA) to conduct vibration, shock and environmental testing on three Rowley containers with contents. The contents consist of a Transportable Collective Protective System (TCPS). The TCPS, manufactured by IIC/Dover Inc., is a chemical warfare tent. Personnel can enter the tent, remove protective clothing and perform duties in an uncontaminated environment. The purpose of this project was to determine if the Rowley containers would be able to contain and protect the TCPS during world-wide shipment, storage, and handling.

  4. Knockdown of the sodium-dependent phosphate co-transporter 2b (NPT2b) suppresses lung tumorigenesis.

    PubMed

    Hong, Seong-Ho; Minai-Tehrani, Arash; Chang, Seung-Hee; Jiang, Hu-Lin; Lee, Somin; Lee, Ah-Young; Seo, Hwi Won; Chae, Chanhee; Beck, George R; Cho, Myung-Haing

    2013-01-01

    The sodium-dependent phosphate co-transporter 2b (NPT2b) plays an important role in maintaining phosphate homeostasis. In previous studies, we have shown that high dietary inorganic phosphate (Pi) consumption in mice stimulated lung tumorigenesis and increased NPT2b expression. NPT2b has also been found to be highly expressed in human lung cancer tissues. The association of high expression of NPT2b in the lung with poor prognosis in oncogenic lung diseases prompted us to test whether knockdown of NPT2b may regulate lung cancer growth. To address this issue, aerosols that contained small interfering RNA (siRNA) directed against NPT2b (siNPT2b) were delivered into the lungs of K-ras (LA1) mice, which constitute a murine model reflecting human lung cancer. Our results clearly showed that repeated aerosol delivery of siNPT2b successfully suppressed lung cancer growth and decreased cancer cell proliferation and angiogenesis, while facilitating apoptosis. These results strongly suggest that NPT2b plays a role lung tumorigenesis and represents a novel target for lung cancer therapy. PMID:24194864

  5. The Arabidopsis thylakoid transporter PHT4;1 influences phosphate availability for ATP synthesis and plant growth.

    PubMed

    Karlsson, Patrik M; Herdean, Andrei; Adolfsson, Lisa; Beebo, Azeez; Nziengui, Hugues; Irigoyen, Sonia; Ünnep, Renáta; Zsiros, Ottó; Nagy, Gergely; Garab, Győző; Aronsson, Henrik; Versaw, Wayne K; Spetea, Cornelia

    2015-10-01

    The Arabidopsis phosphate transporter PHT4;1 was previously localized to the chloroplast thylakoid membrane. Here we investigated the physiological consequences of the absence of PHT4;1 for photosynthesis and plant growth. In standard growth conditions, two independent Arabidopsis knockout mutant lines displayed significantly reduced leaf size and biomass but normal phosphorus content. When mutants were grown in high-phosphate conditions, the leaf phosphorus levels increased and the growth phenotype was suppressed. Photosynthetic measurements indicated that in the absence of PHT4;1 stromal phosphate was reduced to levels that limited ATP synthase activity. This resulted in reduced CO2 fixation and accumulation of soluble sugars, limiting plant growth. The mutants also displayed faster induction of non-photochemical quenching than the wild type, in line with the increased contribution of ΔpH to the proton-motive force across thylakoids. Small-angle neutron scattering showed a smaller lamellar repeat distance, whereas circular dichroism spectroscopy indicated a perturbed long-range order of photosystem II (PSII) complexes in the mutant thylakoids. The absence of PHT4;1 did not alter the PSII repair cycle, as indicated by wild-type levels of phosphorylation of PSII proteins, inactivation and D1 protein degradation. Interestingly, the expression of genes for several thylakoid proteins was downregulated in the mutants, but the relative levels of the corresponding proteins were either not affected or could not be discerned. Based on these data, we propose that PHT4;1 plays an important role in chloroplast phosphate compartmentation and ATP synthesis, which affect plant growth. It also maintains the ionic environment of thylakoids, which affects the macro-organization of complexes and induction of photoprotective mechanisms. PMID:26255788

  6. A Brassica napus PHT1 phosphate transporter, BnPht1;4, promotes phosphate uptake and affects roots architecture of transgenic Arabidopsis.

    PubMed

    Ren, Feng; Zhao, Cai-Zhi; Liu, Chun-Sen; Huang, Ke-Lin; Guo, Qian-Qian; Chang, Li-Li; Xiong, Huan; Li, Xue-Bao

    2014-12-01

    Phosphorus (P) is one of the essential nutrient elements for plant development. In this work, BnPht1;4 gene, encoding a phosphate transporter of PHT1 family, was isolated from Brassica napus. BnPht1;4 possesses the major characteristic of PHT1 high-affinity Pi transporters in plants, such as plasma-membrane localization and 12 transmembrane-spanning domains. Quantitative reverse-transcription PCR analysis and promoter activity assay showed BnPht1;4 was inert in plants under Pi sufficient conditions. However, expression of this gene was remarkably enhanced in roots under Pi deficient conditions. Interestingly, under low Pi conditions, its promoter activity is impaired in tips of elongated roots, suggesting that the high-affinity Pi transporter may be not involved in low Pi response at root tip area. The experimental results also indicated that BnPht1;4 induction by Pi deficiency is dependent on the existence of sugar. In 35S:BnPht1;4 transgenic Arabidopsis, the increase of Pi availability resulted in the change of root architecture under Pi deficient conditions, showing longer primary roots and lower lateral root density than that of wild type. By cis-element analysis, two P1BS and two W-box elements were found in BnPht1;4 promoter. Yeast one-hybrid assay indicated that PHR1 could bind to the BnPht1;4 promoter. P1BS elements in BnPht1;4 promoter are essential for BnPht1;4 induction in Pi starvation response. Furthermore, WRKY75 could bind to the BnPht1;4 promoter, in which W-box elements are important for this binding. These results indicated BnPht1;4 may be dually controlled by two family regulators under low Pi responses. Thus, our data on the regulative mechanism of high-affinity Pi transporter in Pi starvation response will be valuable for B. napus molecular agriculture. PMID:25194430

  7. Adaptation of epithelial sodium-dependent phosphate transport in jejunum and kidney of hens to variations in dietary phosphorus intake.

    PubMed

    Huber, K; Hempel, R; Rodehutscord, M

    2006-11-01

    The objective of this study was to explore the homeostatic response of jejunal and renal epithelia regarding the inorganic phosphate (P(i)) transport capacities to variations in dietary total phosphorus (tP) supply in hens. Adaptive processes were determined by quantitative measures of intake and excretion, P(i) transport studies across brush border membranes, and semiquantitative detection of sodium-dependent phosphate transporters (NaPi II) based on mRNA expression in the jejunum and kidney. Twelve hens (4/group) were adapted to 3 tP feeding levels in a pair-fed manner (60 g/d): low P diet with 0.073% tP, medium P diet with 0.204% tP, and high P diet with 0.343% tP. Excretion was measured during the last 5 d of a 16-d feeding period. After slaughtering, jejunal mucosa and renal cortex were removed. Tissues were used for (32)P uptake studies in brush-border membrane vesicles by rapid filtration technique and NaPi II mRNA expression studies by northern analyses. Plasma P(i) concentrations were additionally measured. The NaPi II transporter mRNA could specifically be detected in chicken jejunum and kidney. Functional parameters of Na(+)-dependent P(i) transport indicated that these transporters were involved in chicken P(i) transport across the apical membranes of jejunal and renal epithelia. Increased tP intake resulted in an increased overall tP excretion. Correlating individual data from all animals by linear regression highlighted that the adaptive decrease of renal P(i) transport capacity and NaPi IIa mRNA expression was associated with an increase in plasma P(i) levels and resulted in a higher tP excretion. Jejunal P(i) transport capacity and NaPi IIb mRNA expression did not react to variations in dietary tP supply. In conclusion, the homeostatic response was mainly based on the adaptive capacity of the kidney in hens. PMID:17032833

  8. Strigolactones are involved in phosphate- and nitrate-deficiency-induced root development and auxin transport in rice.

    PubMed

    Sun, Huwei; Tao, Jinyuan; Liu, Shangjun; Huang, Shuangjie; Chen, Si; Xie, Xiaonan; Yoneyama, Koichi; Zhang, Yali; Xu, Guohua

    2014-12-01

    Strigolactones (SLs) or their derivatives have recently been defined as novel phytohormones that regulate root development. However, it remains unclear whether SLs mediate root growth in response to phosphorus (P) and nitrogen (N) deficiency. In this study, the responses of root development in rice (Oryza sativa L.) to different levels of phosphate and nitrate supply were investigated using wild type (WT) and mutants defective in SL synthesis (d10 and d27) or insensitive to SL (d3). Reduced concentration of either phosphate or nitrate led to increased seminal root length and decreased lateral root density in WT. Limitation of either P or N stimulated SL production and enhanced expression of D10, D17, and D27 and suppressed expression of D3 and D14 in WT roots. Mutation of D10, D27, or D3 caused loss of sensitivity of root response to P and N deficiency. Application of the SL analogue GR24 restored seminal root length and lateral root density in WT and d10 and d27 mutants but not in the d3 mutant, suggesting that SLs were induced by nutrient-limiting conditions and led to changes in rice root growth via D3. Moreover, P or N deficiency or GR24 application reduced the transport of radiolabelled indole-3-acetic acid and the activity of DR5::GUS auxin reporter in WT and d10 and d27 mutants. These findings highlight the role of SLs in regulating rice root development under phosphate and nitrate limitation. The mechanisms underlying this regulatory role involve D3 and modulation of auxin transport from shoots to roots. PMID:24596173

  9. Modeling phosphate transport and removal in a compact bed filled with a mineral-based sorbent for domestic wastewater treatment.

    PubMed

    Herrmann, Inga; Jourak, Amir; Gustafsson, Jon Petter; Hedström, Annelie; Lundström, T Staffan; Viklander, Maria

    2013-11-01

    Phosphorus filter units containing mineral-based sorbents with a high phosphate (PO4) binding capacity have been shown to be appropriate for removing PO4 in the treatment of domestic wastewater in on-site facilities. However, a better understanding of their PO4 removal mechanisms, and reactions that could lead to the formation of PO4 compounds, is required to evaluate the potential utility of candidate sorbents. Models based on data obtained from laboratory-scale experiments with columns of selected materials can be valuable for acquiring such understanding. Thus, in this study the transport and removal of PO4 in experiments with a laboratory-scale column filled with a commercial silicate-based sorbent were modeled, using the hydro-geochemical transport code PHREEQC. The resulting models, that incorporated the dissolution of calcite, kinetic constrains for the dissolution of calcium oxide (CaO) and wollastonite (CaSiO3), and the precipitation of amorphous tricalcium phosphate, Ca3(PO4)2, successfully simulated the removal of PO4 observed in the experiments. PMID:24090737

  10. Modeling phosphate transport and removal in a compact bed filled with a mineral-based sorbent for domestic wastewater treatment

    NASA Astrophysics Data System (ADS)

    Herrmann, Inga; Jourak, Amir; Gustafsson, Jon Petter; Hedström, Annelie; Lundström, T. Staffan; Viklander, Maria

    2013-11-01

    Phosphorus filter units containing mineral-based sorbents with a high phosphate (PO4) binding capacity have been shown to be appropriate for removing PO4 in the treatment of domestic wastewater in on-site facilities. However, a better understanding of their PO4 removal mechanisms, and reactions that could lead to the formation of PO4 compounds, is required to evaluate the potential utility of candidate sorbents. Models based on data obtained from laboratory-scale experiments with columns of selected materials can be valuable for acquiring such understanding. Thus, in this study the transport and removal of PO4 in experiments with a laboratory-scale column filled with a commercial silicate-based sorbent were modeled, using the hydro-geochemical transport code PHREEQC. The resulting models, that incorporated the dissolution of calcite, kinetic constrains for the dissolution of calcium oxide (CaO) and wollastonite (CaSiO3), and the precipitation of amorphous tricalcium phosphate, Ca3(PO4)2, successfully simulated the removal of PO4 observed in the experiments.

  11. Lipid phosphate phosphatase 3 participates in transport carrier formation and protein trafficking in the early secretory pathway.

    PubMed

    Gutiérrez-Martínez, Enric; Fernández-Ulibarri, Inés; Lázaro-Diéguez, Francisco; Johannes, Ludger; Pyne, Susan; Sarri, Elisabet; Egea, Gustavo

    2013-06-15

    The inhibition of phosphatidic acid phosphatase (PAP) activity by propanolol indicates that diacylglycerol (DAG) is required for the formation of transport carriers at the Golgi and for retrograde trafficking to the ER. Here we report that the PAP2 family member lipid phosphate phosphatase 3 (LPP3, also known as PAP2b) localizes in compartments of the secretory pathway from ER export sites to the Golgi complex. The depletion of human LPP3: (i) reduces the number of tubules generated from the ER-Golgi intermediate compartment and the Golgi, with those formed from the Golgi being longer in LPP3-silenced cells than in control cells; (ii) impairs the Rab6-dependent retrograde transport of Shiga toxin subunit B from the Golgi to the ER, but not the anterograde transport of VSV-G or ssDsRed; and (iii) induces a high accumulation of Golgi-associated membrane buds. LPP3 depletion also reduces levels of de novo synthesized DAG and the Golgi-associated DAG contents. Remarkably, overexpression of a catalytically inactive form of LPP3 mimics the effects of LPP3 knockdown on Rab6-dependent retrograde transport. We conclude that LPP3 participates in the formation of retrograde transport carriers at the ER-Golgi interface, where it transitorily cycles, and during its route to the plasma membrane. PMID:23591818

  12. Variables Affecting Two Electron Transport System Assays

    PubMed Central

    Burton, G. Allen; Lanza, Guy R.

    1986-01-01

    Several methodological variables were critical in two commonly used electron transport activity assays. The dehydrogenase assay based on triphenyl formazan production exhibited a nonlinear relationship between formazan production (dehydrogenase activity) and sediment dilution, and linear formazan production occurred for 1 h in sediment slurries. Activity decreased with increased time of sediment storage at 4°C. Extraction efficiencies of formazan from sediment varied with alcohol type; methanol was unsatisfactory. Phosphate buffer (0.06 M) produced higher activity than did either U.S. Environmental Protection Agency reconstituted hard water or Tris buffer sediment diluents. Intracellular formazan crystals were dissolved within minutes when in contact with immersion oil. Greater crystal production (respiration) detected by a tetrazolium salt assay occurred at increased substrate concentrations. Test diluents containing macrophyte exudates produced greater activity than did phosphate buffer, U.S. Environmental Protection Agency water, or ultrapure water diluents. Both assays showed decreases in sediment or bacterial activity through time. PMID:16347067

  13. Plasmodesmata localizing proteins regulate transport and signaling during systemic acquired immunity in plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Systemic acquired resistance (SAR) in plants is mediated by the signaling molecules azelaic acid (AzA),glycerol-3-phosphate (G3P), and salicylic acid (SA).Here, we show that AzA and G3P transport occurs via the symplastic route, which is regulated by channels known as plasmodesmata (PD). In contrast...

  14. Research on advanced transportation systems

    NASA Astrophysics Data System (ADS)

    Nagai, Hirokazu; Hashimoto, Ryouhei; Nosaka, Masataka; Koyari, Yukio; Yamada, Yoshio; Noda, Keiichirou; Shinohara, Suetsugu; Itou, Tetsuichi; Etou, Takao; Kaneko, Yutaka

    1992-08-01

    An overview of the researches on advanced space transportation systems is presented. Conceptual study is conducted on fly back boosters with expendable upper stage rocket systems assuming a launch capacity of 30 tons and returning to the launch site by the boosters, and prospect of their feasibility is obtained. Reviews are conducted on subjects as follows: (1) trial production of 10 tons sub scale engines for the purpose of acquiring hardware data and picking up technical problems for full scale 100 tons thrust engines using hydrocarbon fuels; (2) development techniques for advanced liquid propulsion systems from the aspects of development schedule, cost; (3) review of conventional technologies, and common use of component; (4) oxidant switching propulsion systems focusing on feasibility of Liquefied Air Cycle Engine (LACE) and Compressed Air Cycle Engine (CACE); (5) present status of slosh hydrogen manufacturing, storage, and handling; (6) construction of small high speed dynamometer for promoting research on mini pump development; (7) hybrid solid boosters under research all over the world as low-cost and clean propulsion systems; and (8) high performance solid propellant for upper stage and lower stage propulsion systems.

  15. Urban Transportation Planning Short Course: Evaluation of Alternative Transportation Systems.

    ERIC Educational Resources Information Center

    Federal Highway Administration (DOT), Washington, DC.

    This urban transportation pamphlet delves into the roles of policy groups and technical staffs in evaluating alternative transportation plans, evaluation criteria, systems to evaluate, and evaluation procedures. The introduction admits the importance of subjective, but informed, judgment as an effective tool in weighing alternative transportation…

  16. Radioisotope thermoelectric generator transport trailer system

    NASA Astrophysics Data System (ADS)

    Ard, Kevin E.; King, David A.; Leigh, Harley; Satoh, Juli A.

    1995-01-01

    The Radioisotope Thermoelectric Generator (RTG) Transportation System, designated as System 100, comprises four major systems. The four major systems are designated as the Packaging System (System 120), Trailer System (System 140), Operations and Ancillary Equipment System (System 160), and Shipping and Receiving Facility Transport System (System 180). Packaging System (System 120), including the RTG packaging is licensed (regulatory) hardware; it is certified by the U.S. Department of Energy to be in accordance with Title 10, Code of Federal Regulations, Part 71 (10 CFR 71). System 140, System 160, and System 180 are nonlicensed (nonregulatory) hardware.

  17. Radioisotope thermoelectric generator transport trailer system

    SciTech Connect

    Ard, K.E.; King, D.A.; Leigh, H.; Satoh, J.A.

    1995-01-20

    The Radioisotope Thermoelectric Generator (RTG) Transportation System, designated as System 100, comprises four major systems. The four major systems are designated as the Packaging System (System 120), Trailer System (System 140), Operations and Ancillary Equipment System (System 160), and Shipping and Receiving Facility Transport System (System 180). Packaging System (System 120), including the RTG packaging is licensed (regulatory) hardware; it is certified by the U.S. Department of Energy to be in accordance with Title 10, {ital Code} {ital of} {ital Federal} {ital Regulations}, Part 71 (10 CFR 71). System 140, System 160, and System 180 are nonlicensed (nonregulatory) hardware. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}

  18. Linking Gene Expression in the Intestine to Production of Gametes Through the Phosphate Transporter PITR-1 in Caenorhabditis elegans.

    PubMed

    Balklava, Zita; Rathnakumar, Navin D; Vashist, Shilpa; Schweinsberg, Peter J; Grant, Barth D

    2016-09-01

    Inorganic phosphate is an essential mineral for both prokaryotic and eukaryotic cell metabolism and structure. Its uptake into the cell is mediated by membrane-bound transporters and coupled to Na(+) transport. Mammalian sodium-dependent Pi cotransporters have been grouped into three families NaPi-I, NaPi-II, and NaPi-III. Despite being discovered more than two decades ago, very little is known about requirements for NaPi-III transporters in vivo, in the context of intact animal models. Here we find that impaired function of the Caenorhabditis elegans NaPi-III transporter, pitr-1, results in decreased brood size and dramatically increased expression of vitellogenin by the worm intestine. Unexpectedly, we found that the effects of pitr-1 mutation on vitellogenin expression in the intestine could only be rescued by expression of pitr-1 in the germline, and not by expression of pitr-1 in the intestine itself. Our results indicate the existence of a signal from the germline that regulates gene expression in the intestine, perhaps linking nutrient export from the intestine to production of gametes by the germline. PMID:27449055

  19. Linking Gene Expression in the Intestine to Production of Gametes Through the Phosphate Transporter PITR-1 in Caenorhabditis elegans

    PubMed Central

    Balklava, Zita; Rathnakumar, Navin D.; Vashist, Shilpa; Schweinsberg, Peter J.; Grant, Barth D.

    2016-01-01

    Inorganic phosphate is an essential mineral for both prokaryotic and eukaryotic cell metabolism and structure. Its uptake into the cell is mediated by membrane-bound transporters and coupled to Na+ transport. Mammalian sodium-dependent Pi cotransporters have been grouped into three families NaPi-I, NaPi-II, and NaPi-III. Despite being discovered more than two decades ago, very little is known about requirements for NaPi-III transporters in vivo, in the context of intact animal models. Here we find that impaired function of the Caenorhabditis elegans NaPi-III transporter, pitr-1, results in decreased brood size and dramatically increased expression of vitellogenin by the worm intestine. Unexpectedly, we found that the effects of pitr-1 mutation on vitellogenin expression in the intestine could only be rescued by expression of pitr-1 in the germline, and not by expression of pitr-1 in the intestine itself. Our results indicate the existence of a signal from the germline that regulates gene expression in the intestine, perhaps linking nutrient export from the intestine to production of gametes by the germline. PMID:27449055

  20. Relationship between Nitrite Reduction and Active Phosphate Uptake in the Phosphate-Accumulating Denitrifier Pseudomonas sp. Strain JR 12

    PubMed Central

    Barak, Yoram; van Rijn, Jaap

    2000-01-01

    Phosphate uptake by the phosphate-accumulating denitrifier Pseudomonas sp. JR12 was examined with different combinations of electron and carbon donors and electron acceptors. Phosphate uptake in acetate-supplemented cells took place with either oxygen or nitrate but did not take place when nitrite served as the final electron acceptor. Furthermore, nitrite reduction rates by this denitrifier were shown to be significantly reduced in the presence of phosphate. Phosphate uptake assays in the presence of the H+-ATPase inhibitor N,N′-dicyclohexylcarbodiimide (DCCD), in the presence of the uncoupler carbonyl cyanide 3-chlorophenylhydrazone (CCCP), or with osmotic shock-treated cells indicated that phosphate transport over the cytoplasmic membrane of this bacterium was mediated by primary and secondary transport systems. By examining the redox transitions of whole cells at 553 nm we found that phosphate addition caused a significant oxidation of a c-type cytochrome. Based on these findings, we propose that this c-type cytochrome serves as an intermediate in the electron transfer to both nitrite reductase and the site responsible for active phosphate transport. In previous studies with this bacterium we found that the oxidation state of this c-type cytochrome was significantly higher in acetate-supplemented, nitrite-respiring cells (incapable of phosphate uptake) than in phosphate-accumulating cells incubated with different combinations of electron donors and acceptors. Based on the latter finding and results obtained in the present study it is suggested that phosphate uptake in this bacterium is subjected to a redox control of the active phosphate transport site. By means of this mechanism an explanation is provided for the observed absence of phosphate uptake in the presence of nitrite and inhibition of nitrite reduction by phosphate in this organism. The implications of these findings regarding denitrifying, phosphate removal wastewater plants is discussed. PMID

  1. Phase stable RF transport system

    DOEpatents

    Curtin, Michael T.; Natter, Eckard F.; Denney, Peter M.

    1992-01-01

    An RF transport system delivers a phase-stable RF signal to a load, such as an RF cavity of a charged particle accelerator. A circuit generates a calibration signal at an odd multiple frequency of the RF signal where the calibration signal is superimposed with the RF signal on a common cable that connects the RF signal with the load. Signal isolating diplexers are located at both the RF signal source end and load end of the common cable to enable the calibration to be inserted and extracted from the cable signals without any affect on the RF signal. Any phase shift in the calibration signal during traverse of the common cable is then functionally related to the phase shift in the RF signal. The calibration phase shift is used to control a phase shifter for the RF signal to maintain a stable RF signal at the load.

  2. Modulation of intestinal calcium and phosphate transport in young goats fed a nitrogen- and/or calcium-reduced diet.

    PubMed

    Elfers, Kristin; Wilkens, Mirja R; Breves, Gerhard; Muscher-Banse, Alexandra S

    2015-12-28

    Feeding ruminants a reduced N diet is a common approach to reduce N output based on rumino-hepatic circulation. However, a reduction in N intake caused massive changes in Ca and inorganic phosphate (Pi) homoeostasis in goats. Although a single dietary Ca reduction stimulated intestinal Ca absorption in a calcitriol-dependent manner, a concomitant reduction of Ca and N supply led to a decrease in calcitriol, and therefore a modulation of intestinal Ca and Pi absorption. The aim of this study was to examine the potential effects of dietary N or Ca reduction separately on intestinal Ca and Pi transport in young goats. Animals were allocated to a control, N-reduced, Ca-reduced or combined N- and Ca-reduced diet for about 6-8 weeks, whereby N content was reduced by 25 % compared with recommendations. In Ussing chamber experiments, intestinal Ca flux rates significantly decreased in goats fed a reduced N diet, whereas Pi flux rates were unaffected. In contrast, a dietary Ca reduction stimulated Ca flux rates and decreased Pi flux rates. The combined dietary N and Ca reduction withdrew the stimulating effect of dietary Ca reduction on Ca flux rates. The expression of Ca-transporting proteins decreased with a reduced N diet too, whereas Pi-transporting proteins were unaffected. In conclusion, a dietary N reduction decreased intestinal Ca transport by diminishing Ca-transporting proteins, which became clear during simultaneous N and Ca reduction. Therefore, N supply in young ruminant nutrition is of special concern for intestinal Ca transport. PMID:26443238

  3. Classical transport in disordered systems

    NASA Astrophysics Data System (ADS)

    Papaioannou, Antonios

    This thesis reports on the manifestation of structural disorder on molecular transport and it consists of two parts. Part I discusses the relations between classical transport and the underlying structural complexity of the system. Both types of molecular diffusion, namely Gaussian and non- Gaussian are presented and the relevant time regimes are discussed. In addition the concept of structural universality is introduced and connected with the diffusion metrics. One of the most robust techniques for measuring molecular mean square displacements is magnetic resonance. This method requires encoding and subsequently reading out after an experimentally controlled time, a phase φ to the spins using magnetic field gradients. The main limitation for probing short diffusion lengths L(t) ˜ 1micro m with magnetic resonance is the requirement to encode and decode the phase φ in very short time intervals. Therefore, to probe such displacements a special probe was developed equipped with a gradient coil capable of delivering magnetic field gradients of approximately 90 G/cmA . The design of the probe is reported. Part I also includes a discussion of experiments of transport in two qualitatively different disordered phantoms and reports on a direct observation of universality in one-dimension. The results reveal the universal power law scaling of the diffusion coefficient at the long-time regime and illustrate the essence of structural universality by experimentally determining the structure correlation function of the phantoms. In addition, the scaling of the diffusive permeability of the phantoms with respect to the pore size is investigated. Additional work presented includes a detailed study of adsorption of methane gas in Vycor disordered glass. The techniques described in Part I of this thesis are widely used for measuring structural parameters of porous media, such as the surface-to-volume ratio or diffusive permeability. Part II of this thesis discusses the

  4. Renal transport of bisphosphonates: accumulation by renal cortical slices enhanced by calcium phosphate ions

    SciTech Connect

    Troehler, U.; Bonjour, J.P.; Fleisch, H.

    1985-07-01

    Bisphosphonates have been recognized as useful therapeutic agents in metabolic bone disease. Earlier studies showed a net renal secretion of 1-hydroxy-ethylidene-1,1-bisphosphonate (HEBP). They suggested a renal cellular uptake of this compound. The authors further studied this concept by investigating the uptake in vitro of /sup 14/C-HEBP by rat renal cortex slices. HEBP was accumulated against a concentration gradient, a process that was dependent on time, temperature, and substrate concentration. Unlike that of /sup 3/H-p-aminohippurate, the uptake was not affected by change in medium Na+ or glucose and acetate concentration, or by anoxia and various metabolic inhibitors. It was, however, markedly increased by raising the medium calcium and inorganic phosphate concentration. Equilibrium dialysis with renal cortex homogenates suggests that HEBP binds to a cytosolic macromolecule through a process that exhibits saturability and calcium dependency. In conclusion, the results suggest that the bisphosphonate HEBP can penetrate kidney cells by a process that does not appear to be energy dependent, but is markedly influenced by the extracellular calcium-phosphate concentration.

  5. Glycerol-3-phosphate is a critical mobile inducer of systemic immunity in plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Glycerol-3-phosphate (G3P) is an important metabolite that contributes to the growth and disease-related physiologies of prokaryotes, plants, animals and humans alike. Here we show that G3P serves as the inducer of an important form of broad-spectrum immunity in plants, termed systemic acquired resi...

  6. 21 CFR 862.1315 - Galactose-1-phosphate uridyl transferase test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Galactose-1-phosphate uridyl transferase test system. 862.1315 Section 862.1315 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES...

  7. 21 CFR 862.1315 - Galactose-1-phosphate uridyl transferase test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Galactose-1-phosphate uridyl transferase test system. 862.1315 Section 862.1315 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... hereditary disease galactosemia (disorder of galactose metabolism) in infants. (b) Classification. Class II....

  8. 21 CFR 862.1315 - Galactose-1-phosphate uridyl transferase test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Galactose-1-phosphate uridyl transferase test system. 862.1315 Section 862.1315 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... hereditary disease galactosemia (disorder of galactose metabolism) in infants. (b) Classification. Class II....

  9. Manned transportation system study - Evaluation of candidate transportation architectures

    NASA Technical Reports Server (NTRS)

    Lance, Nicholas; Klemer, R.; Sooter, C.

    1992-01-01

    The overall evaluation process, the tool developed to perform the evaluation, and the evaluation results in determining the right approach to meet the nation's mannned transportation needs are presented. To address the various considerations, architecture sets consisting of the candidate transportation systems are constructed. As this methodology results in multiple architectures to examine, an architecture evaluation tool was developed to facilitate the evaluation of the architecture attribute values from the system values of the attributes.

  10. Transport properties of lead phosphate glass doped by cobalt, vanadium and chromium oxides

    NASA Astrophysics Data System (ADS)

    Roumaih, Kh.; Kaiser, M.; Elbatal, Fatma H.; Ali, I. S.

    2011-10-01

    The electrical transport properties were investigated of a glass system of basic composition 50 mol. % Pb3O4-50 mol. % P2O5 containing CoO, Cr2O3 or V2O5 dopanys. The ac conductivity and the thermoelectric power were measured as a function of temperature. Properties such as dielectric constant, loss factor tangent and electrical conductivity are reported in the frequency range 200 Hz-100 kHz and temperature range 300-450 K. The variation in electrical conductivity with temperature was found to depend on the types of transition metal ions involved. The temperature dependence of the frequency exponent, s, was analyzed using different theoretical models. The variation of the thermoelectric power with temperature indicated the presence of more than one conduction mechanism for the investigated samples. This result was confirmed with the results of the dielectric properties at different frequencies. The introduction of cobalt ions in glass formers improves the electrical properties of non-crystalline ionic conductors.

  11. Molecular cloning and functional analysis of a H(+)-dependent phosphate transporter gene from the ectomycorrhizal fungus Boletus edulis in southwest China.

    PubMed

    Wang, Junling; Li, Tao; Wu, Xiaogang; Zhao, Zhiwei

    2014-01-01

    Phosphate transporters (PTs), as entry points for phosphorus (P) in organisms, are involved in a number of P nutrition processes such as phosphate uptake, transport, and transfer. In the study, a PT gene 1632 bp long (named BePT) was cloned, identified, and functionally characterized from Boletus edulis. BePT was expected to encode a polypeptide with 543 amino acid residues. The BePT polypeptide belonged to the major facilitator superfamily and showed a high degree of sequence identity to the Pht1 family. A topology model revealed that BePT exhibited 12 transmembrane helices, divided into two halves, and connected by a large hydrophilic loop in the middle. A yeast mutant complementation analysis suggested that BePT was a functional PT which mediated orthophosphate uptake of yeast at micromolar concentrations. Green fluorescent protein-BePT fusion proteins expressed were extensively restricted to the plasma membrane in BePT transformed yeast, and its activity was dependent on electrochemical membrane potential. In vitro, quantitative PCR confirmed that the expression of BePT was significantly upregulated at lower phosphorus availability, which may enhance phosphate uptake and transport under phosphate starvation. Our results suggest that BePT plays a key role in phosphate acquisition in the ectomycorrhizal fungus B. edulis. PMID:24863474

  12. Products and stability of phosphate reactions with lead under freeze-thaw cycling in simple systems.

    PubMed

    Hafsteinsdóttir, Erla G; White, Duanne A; Gore, Damian B; Stark, Scott C

    2011-12-01

    Orthophosphate fixation of metal contaminated soils in environments that undergo freeze-thaw cycles is understudied. Freeze-thaw cycling potentially influences the reaction rate, mineral chemical stability and physical breakdown of particles during fixation. This study determines what products form when phosphate (triple superphosphate [Ca(H(2)PO(4))(2)] or sodium phosphate [Na(3)PO(4)]) reacts with lead (PbSO(4) or PbCl(2)) in simple chemical systems in vitro, and assesses potential changes in formation during freeze-thaw cycles. Systems were subjected to multiple freeze-thaw cycles from +10 °C to -20 °C and then analysed by X-ray diffractometry. Pyromorphite formed in all systems and was stable over multiple freeze-thaw cycles. Low temperature lead orthophosphate reaction efficiency varied according to both phosphate and lead source; the most time-efficient pyromorphite formation was observed when PbSO(4) and Na(3)PO(4) were present together. These findings have implications for the manner in which metal contaminated materials in freezing ground can be treated with phosphate. PMID:21907472

  13. Effect of Dietary Nutrient Density on Small Intestinal Phosphate Transport and Bone Mineralization of Broilers during the Growing Period.

    PubMed

    Li, Jianhui; Yuan, Jianmin; Miao, Zhiqiang; Song, Zhigang; Yang, Yu; Tian, Wenxia; Guo, Yuming

    2016-01-01

    A 2 × 4 factorial experiment was conducted to determine the effects of dietary nutrient density on growth performance, small intestinal epithelial phosphate transporter expression, and bone mineralization of broiler chicks fed with diets with different nutrient densities and nonphytate phosphorus (NPP) levels. The broilers were fed with the same starter diets from 0 to 21 days of age. In the grower phase (day 22 to 42), the broilers were randomly divided into eight groups according to body weight. Relatively high dietary nutrient density (HDND) and low dietary nutrient density (LDND) diets were assigned metabolic energy (ME) values of 3,150 and 2,950 kcal/kg, respectively. Crude protein and essential amino acid levels were maintained in the same proportion as ME to prepare the two diet types. NPP levels were 0.25%, 0.30%, 0.35%, and 0.40% of the diets. Results showed that a HDND diet significantly increased the body weight gain (BWG) of broilers and significantly decreased the feed conversion ratio and NPP consumed per BWG. HDND significantly decreased tibial P content of the broilers. Conversely, mRNA expression of NaPi-IIb and protein expression of calbindin were significantly increased in the intestine of broilers fed a HDND diet. HDND also increased vitamin D receptor (VDR) expression, especially at a relatively low dietary NPP level (0.25%). The mRNA expression of NaPi-IIa in the kidneys was significantly increased at a relatively low dietary NPP level (0.25%) to maintain P balance. Tibial P, calcium, and ash content were significantly decreased, as were calbindin and VDR expression levels in the intestine at a low NPP level. Therefore, HDND improved the growth rate of broilers and increased the expression of phosphate and calcium transporter in the small intestine, but adversely affected bone mineralization. PMID:27100791

  14. Effect of Dietary Nutrient Density on Small Intestinal Phosphate Transport and Bone Mineralization of Broilers during the Growing Period

    PubMed Central

    Miao, Zhiqiang; Song, Zhigang; Yang, Yu; Tian, Wenxia; Guo, Yuming

    2016-01-01

    A 2 × 4 factorial experiment was conducted to determine the effects of dietary nutrient density on growth performance, small intestinal epithelial phosphate transporter expression, and bone mineralization of broiler chicks fed with diets with different nutrient densities and nonphytate phosphorus (NPP) levels. The broilers were fed with the same starter diets from 0 to 21 days of age. In the grower phase (day 22 to 42), the broilers were randomly divided into eight groups according to body weight. Relatively high dietary nutrient density (HDND) and low dietary nutrient density (LDND) diets were assigned metabolic energy (ME) values of 3,150 and 2,950 kcal/kg, respectively. Crude protein and essential amino acid levels were maintained in the same proportion as ME to prepare the two diet types. NPP levels were 0.25%, 0.30%, 0.35%, and 0.40% of the diets. Results showed that a HDND diet significantly increased the body weight gain (BWG) of broilers and significantly decreased the feed conversion ratio and NPP consumed per BWG. HDND significantly decreased tibial P content of the broilers. Conversely, mRNA expression of NaPi-IIb and protein expression of calbindin were significantly increased in the intestine of broilers fed a HDND diet. HDND also increased vitamin D receptor (VDR) expression, especially at a relatively low dietary NPP level (0.25%). The mRNA expression of NaPi-IIa in the kidneys was significantly increased at a relatively low dietary NPP level (0.25%) to maintain P balance. Tibial P, calcium, and ash content were significantly decreased, as were calbindin and VDR expression levels in the intestine at a low NPP level. Therefore, HDND improved the growth rate of broilers and increased the expression of phosphate and calcium transporter in the small intestine, but adversely affected bone mineralization. PMID:27100791

  15. Time-dependent, three-dimensional flow and mass transport during solution growth of potassium titanyl phosphate

    NASA Astrophysics Data System (ADS)

    Vartak, Bhushan; Yeckel, Andrew; Derby, Jeffrey J.

    2005-08-01

    A finite-element, numerical model is used to compute time-dependent, three-dimensional fluid flow, mass transfer, and continuum growth kinetics in the potassium titanyl phosphate (KTP) solution crystal growth system of Bordui et al. The effects of a periodically-reversing crystal rotation schedule are analyzed for two different crystal-mounting geometries. Results suggest a lower probability of the occurrence of defects when the mounting geometry is designed to take advantage of periodic flow reversal effects on the supersaturation field.

  16. A Conserved Two-Component Signal Transduction System Controls the Response to Phosphate Starvation in Bifidobacterium breve UCC2003

    PubMed Central

    Alvarez-Martin, Pablo; Fernández, Matilde; O'Connell-Motherway, Mary; O'Connell, Kerry Joan; Sauvageot, Nicolas; Fitzgerald, Gerald F.; MacSharry, John; Zomer, Aldert

    2012-01-01

    This work reports on the identification and molecular characterization of the two-component regulatory system (2CRS) PhoRP, which controls the response to inorganic phosphate (Pi) starvation in Bifidobacterium breve UCC2003. The response regulator PhoP was shown to bind to the promoter region of pstSCAB, specifying a predicted Pi transporter system, as well as that of phoU, which encodes a putative Pi-responsive regulatory protein. This interaction is assumed to cause transcriptional modulation under conditions of Pi limitation. Our data suggest that the phoRP genes are subject to positive autoregulation and, together with pstSCAB and presumably phoU, represent the complete regulon controlled by the phoRP-encoded 2CRS in B. breve UCC2003. Determination of the minimal PhoP binding region combined with bioinformatic analysis revealed the probable recognition sequence of PhoP, designated here as the PHO box, which together with phoRP is conserved among many high-GC-content Gram-positive bacteria. The importance of the phoRP 2CRS in the response of B. breve to Pi starvation conditions was confirmed by analysis of a B. breve phoP insertion mutant which exhibited decreased growth under phosphate-limiting conditions compared to its parent strain UCC2003. PMID:22635988

  17. A National MagLev Transportation System

    NASA Technical Reports Server (NTRS)

    Wright, Michael R.

    2003-01-01

    The case for a national high-speed magnetic-levitation (MagLev) transportation system is presented. Focus is on current issues facing the country, such as national security, the economy, transportation, technology, and the environment. NASA s research into MagLev technology for launch assist is also highlighted. Further, current socio-cultural norms regarding motor-vehicle-based transportation systems are questioned in light of the problems currently facing the U.S. The multidisciplinary benefits of a long-distance MagLev system support the idea that such a system would be an important element of a truly multimodal U.S. transportation infrastructure.

  18. Transportation Planning with Immune System Derived Approach

    NASA Astrophysics Data System (ADS)

    Sugiyama, Kenji; Yaji, Yasuhito; Ootsuki, John Takuya; Fujimoto, Yasutaka; Sekiguchi, Takashi

    This paper presents an immune system derived approach for planning transportation of materials between manufacturing processes in the factory. Transportation operations are modeled by Petri Net, and divided into submodels. Transportation orders are derived from the firing sequences of those submodels through convergence calculation by the immune system derived excitation and suppression operations. Basic evaluation of this approach is conducted by simulation-based investigation.

  19. Glucose-1-Phosphate Transport into Protoplasts and Chloroplasts from Leaves of Arabidopsis1

    PubMed Central

    Fettke, Joerg; Malinova, Irina; Albrecht, Tanja; Hejazi, Mahdi; Steup, Martin

    2011-01-01

    Almost all glucosyl transfer reactions rely on glucose-1-phosphate (Glc-1-P) that either immediately acts as glucosyl donor or as substrate for the synthesis of the more widely used Glc dinucleotides, ADPglucose or UDPglucose. In this communication, we have analyzed two Glc-1-P-related processes: the carbon flux from externally supplied Glc-1-P to starch by either mesophyll protoplasts or intact chloroplasts from Arabidopsis (Arabidopsis thaliana). When intact protoplasts or chloroplasts are incubated with [U-14C]Glc-1-P, starch is rapidly labeled. Incorporation into starch is unaffected by the addition of unlabeled Glc-6-P or Glc, indicating a selective flux from Glc-1-P to starch. However, illuminated protoplasts incorporate less 14C into starch when unlabeled bicarbonate is supplied in addition to the 14C-labeled Glc-1-P. Mesophyll protoplasts incubated with [U-14C]Glc-1-P incorporate 14C into the plastidial pool of adenosine diphosphoglucose. Protoplasts prepared from leaves of mutants of Arabidopsis that lack either the plastidial phosphorylase or the phosphoglucomutase isozyme incorporate 14C derived from external Glc-1-P into starch, but incorporation into starch is insignificant when protoplasts from a mutant possessing a highly reduced ADPglucose pyrophosphorylase activity are studied. Thus, the path of assimilatory starch biosynthesis initiated by extraplastidial Glc-1-P leads to the plastidial pool of adenosine diphosphoglucose, and at this intermediate it is fused with the Calvin cycle-driven route. Mutants lacking the plastidial phosphoglucomutase contain a small yet significant amount of transitory starch. PMID:21115809

  20. The sodium-phosphate co-transporter SLC34A2, and pulmonary alveolar microlithiasis: Presentation of an inbred family and a novel truncating mutation in exon 3

    PubMed Central

    Vismara, Marco Favio Michele; Colao, Emma; Fabiani, Fernanda; Bombardiere, Francesco; Tamburrini, Oscar; Alessio, Caterina; Manti, Francesco; Pelaia, Gerolamo; Romeo, Pasquale; Iuliano, Rodolfo; Perrotti, Nicola

    2015-01-01

    Pulmonary alveolar microlithiasis is a disorder in which many tiny fragments (microliths) of calcium phosphate gradually accumulate in alveoli. Loss of function mutations in the gene SLC34A2 coding for the sodium phosphate co-transporter (NaPi-IIb) are responsible for genetic forms of alveolar microlithiasis. We now report a consanguineous Italian family from Calabria with two affected members segregating alveolar microlithiasis in a recessive fashion. We describe, for the first time, a novel loss of function mutation in the gene coding for NaPi-IIb. A careful description of the clinical phenotype is provided together with technical details for direct sequencing of the gene. PMID:26744662

  1. STARS: The Space Transportation Architecture Risk System

    NASA Technical Reports Server (NTRS)

    Greenberg, Joel S.

    1997-01-01

    Because of the need to perform comparisons between transportation systems that are likely to have significantly different levels of risk, both because of differing degrees of freedom in achieving desired performance levels and their different states of development and utilization, an approach has been developed for performing early comparisons of transportation architectures explicitly taking into account quantitative measures of uncertainty and resulting risk. The approach considers the uncertainty associated with the achievement of technology goals, the effect that the achieved level of technology will have on transportation system performance and the relationship between transportation system performance/capability and the ability to accommodate variations in payload mass. The consequences of system performance are developed in terms of expected values and associated standard deviations of nonrecurring, recurring and the present value of transportation system life cycle cost. Typical results are presented to illustrate the application of the methodology.

  2. Structure and Expression Profile of the Phosphate Pht1 Transporter Gene Family in Mycorrhizal Populus trichocarpa1[W

    PubMed Central

    Loth-Pereda, Verónica; Orsini, Elena; Courty, Pierre-Emmanuel; Lota, Frédéric; Kohler, Annegret; Diss, Loic; Blaudez, Damien; Chalot, Michel; Nehls, Uwe; Bucher, Marcel; Martin, Francis

    2011-01-01

    Gene networks involved in inorganic phosphate (Pi) acquisition and homeostasis in woody perennial species able to form mycorrhizal symbioses are poorly known. Here, we describe the features of the 12 genes coding for Pi transporters of the Pht1 family in poplar (Populus trichocarpa). Individual Pht1 transporters play distinct roles in acquiring and translocating Pi in different tissues of mycorrhizal and nonmycorrhizal poplar during different growth conditions and developmental stages. Pi starvation triggered the up-regulation of most members of the Pht1 family, especially PtPT9 and PtPT11. PtPT9 and PtPT12 showed a striking up-regulation in ectomycorrhizas and endomycorrhizas, whereas PtPT1 and PtPT11 were strongly down-regulated. PtPT10 transcripts were highly abundant in arbuscular mycorrhiza (AM) roots only. PtPT8 and PtPT10 are phylogenetically associated to the AM-inducible Pht1 subfamily I. The analysis of promoter sequences revealed conserved motifs similar to other AM-inducible orthologs in PtPT10 only. To gain more insight into gene regulatory mechanisms governing the AM symbiosis in woody plant species, the activation of the poplar PtPT10 promoter was investigated and detected in AM of potato (Solanum tuberosum) roots. These results indicated that the regulation of AM-inducible Pi transporter genes is conserved between perennial woody and herbaceous plant species. Moreover, poplar has developed an alternative Pi uptake pathway distinct from AM plants, allowing ectomycorrhizal poplar to recruit PtPT9 and PtPT12 to cope with limiting Pi concentrations in forest soils. PMID:21705655

  3. Novel bioactive composite bone cements based on the beta-tricalcium phosphate-monocalcium phosphate monohydrate composite cement system.

    PubMed

    Huan, Zhiguang; Chang, Jiang

    2009-05-01

    Bioactive composite bone cements were obtained by incorporation of tricalcium silicate (Ca3SiO5, C3S) into a brushite bone cement composed of beta-tricalcium phosphate [beta-Ca3(PO4)2, beta-TCP] and monocalcium phosphate monohydrate [Ca(H2PO4)2.H2O, MCPM], and the properties of the new cements were studied and compared with pure brushite cement. The results indicated that the injectability, setting time and short- and long-term mechanical strength of the material are higher than those of pure brushite cement, and the compressive strength of the TCP/MCPM/C3S composite paste increased with increasing aging time. Moreover, the TCP/MCPM/C3S specimens showed significantly improved in vitro bioactivity in simulated body fluid and similar degradability in phosphate-buffered saline as compared with brushite cement. Additionally, the reacted TCP/MCPM/C3S paste possesses the ability to stimulate osteoblast proliferation and promote osteoblastic differentiation of the bone marrow stromal cells. The results indicated that the TCP/MCPM/C3S cements may be used as a bioactive material for bone regeneration, and might have significant clinical advantage over the traditional beta-TCP/MCPM brushite cement. PMID:18996779

  4. Dexamethasone modulates rat renal brush border membrane phosphate transporter mRNA and protein abundance and glycosphingolipid composition.

    PubMed Central

    Levi, M; Shayman, J A; Abe, A; Gross, S K; McCluer, R H; Biber, J; Murer, H; Lötscher, M; Cronin, R E

    1995-01-01

    Glucocorticoids are important regulators of renal phosphate transport. This study investigates the role of alterations in renal brush border membrane (BBM) sodium gradient-dependent phosphate transport (Na-Pi cotransporter) mRNA and protein abundance in the dexamethasone induced inhibition of Na-Pi cotransport in the rat. Dexamethasone administration for 4 d caused a 1.5-fold increase in the Vmax of Na-Pi cotransport (1785 +/- 119 vs. 2759 +/- 375 pmol/5 s per mg BBM protein in control, P < 0.01), which was paralleled by a 2.5-fold decrease in the abundance of Na-Pi mRNA and Na-Pi protein. There was also a 1.7-fold increase in BBM glucosylceramide content (528 +/- 63 vs. 312 +/- 41 ng/mg BBM protein in control, P < 0.02). To determine whether the alteration in glucosylceramide content per se played a functional role in the decrease in Na-Pi cotransport, control rats were treated with the glucosylceramide synthase inhibitor, D-threo-1-phenyl-2-decanoyl-amino-3-morpholino-1-propanol (PDMP). The resultant 1.5-fold decrease in BBM glucosylceramide content (199 +/- 19 vs. 312 +/- 41 ng/mg BBM protein in control, P < 0.02) was associated with a 1.4-fold increase in Na-Pi cotransport activity (1422 +/- 73 vs. 1048 +/- 85 pmol/5 s per mg BBM protein in control, P < 0.01), and a 1.5-fold increase in BBM Na-Pi protein abundance. Thus, dexamethasone-induced inhibition of Na-Pi cotransport is associated with a decrease in BBM Na-Pi cotransporter abundance, and an increase in glucosylceramide. Since primary alteration in BBM glucosylceramide content per se directly and selectively modulates BBM Na-Pi cotransport activity and Na-Pi protein abundance, we propose that the increase in BBM glucosylceramide content plays an important role in mediating the inhibitory effect of dexamethasone on Na-Pi cotransport activity. Images PMID:7615789

  5. The transportation operations system: A description

    SciTech Connect

    Best, R.E.; Danese, F.L.; Dixon, L.D.; Peterson, R.W. ); Pope, R.B. )

    1990-01-01

    This paper presents a description of the system for transporting radioactive waste that may be deployed to accomplish the assigned system mission, which includes accepting spent nuclear fuel (SNF) and high-level radioactive waste (HLW) from waste generator sites and transporting them to the FWMS destination facilities. The system description presented here contains, in part, irradiated fuel and waste casks, ancillary equipments, truck, rail, and barge transporters, cask and vehicle traffic management organizations, maintenance facilities, and other operations elements. The description is for a fully implemented system, which is not expected to be achieved, however, until several years after initial operations. 6 figs.

  6. Systems Studies of DDT Transport

    ERIC Educational Resources Information Center

    Harrison, H. L.; And Others

    1970-01-01

    Major consequences of present and additional environmental quantities of DDT pesticide are predictable by mathematical models of transport, accumulation and concentration mechanisms in the Wisconsin regional ecosystem. High solubility and stability produce increased DDT concentrations at high organism trophic levels within world biosphere…

  7. Cloning and characterization of a phosphate transporter gene in Dunaliella salina.

    PubMed

    Li, Shao-He; Xia, Bing-Bing; Zhang, Chi; Cao, Jiao; Bai, Lin-Han

    2012-08-01

    The full-length cDNA of a Na(+) -dependent Pi transport gene (DsSPT1) in Dunaliella salina was cloned by 3' and 5' Rapid Amplification of cDNA Ends (RACE), with an open reading frame (ORF) encoding 716 predicted amino acids, which exhibited 60.5% identity to that of Na(+) -dependent Pi transport 1 (DvSPT1) from Dunaliella viridis. Hydrophobicity and secondary structure prediction revealed 11 conserved transmembrane domains similar to those found in DvSPT1 from D. viridis and PHO89 from Saccharomyces cerevisiae. The result of real-time quantitative PCR showed that expression level of DsSPT1 was enhanced at first and reached its peak at 90 min after salt stress; however, D. salina cells rapidly absorbed extracellular inorganic phosphorus which was determined by Inductively Coupled Plasma Mass Spectrometry (ICP-MS) during the first 5 min under salt stress. It suggested that D. salina on the absorption of inorganic phosphorus was regulated at DsSPTI posttranslational level. PMID:22052620

  8. Proton/Phosphate Stoichiometry in Uptake of Inorganic Phosphate by Cultured Cells of Catharanthus roseus (L.) G. Don

    PubMed Central

    Sakano, Katsuhiro

    1990-01-01

    Upon absorption of phosphate, cultured cells of Catharanthus roseus (L.) G. Don caused a rapid alkalinization of the medium in which they were suspended. The alkalinization continued until the added phosphate was completely exhausted from the medium, at which time the pH of the medium started to drop sharply toward the original pH value. Phosphate exposure caused the pH of the medium to increase from pH 3.5 to values as high as 5.8, while the rate of phosphate uptake was constant throughout (10-17 micromoles per hour per gram fresh weight). This indicates that no apparent pH optimum exists for the phosphate uptake by the cultured cells. The amount of protons cotransported with phosphate was calculated from the observed pH change up to the maximum alkalinization and the titration curve of the cell suspension. Proton/phosphate transport stoichiometry ranged from less than unity to 4 according to the amount of phosphate applied. At low phosphate doses, the stoichiometries were close to 4, while at high phosphate doses, smaller stoichiometries were observed. This suggests that, at high phosphate doses, activation of the proton pump is induced by the longer lasting proton influx acidifying the cytoplasm. The increased H+ efflux due to the proton pump could partially compensate protons taken up via the proton-phosphate cotransport system. Thus, the H+/H2PO4− stoichiometry of the cotransport is most likely to be 4. PMID:16667491

  9. Transportation Systems. Curriculum Guide for Technology Education.

    ERIC Educational Resources Information Center

    Chastain, Gary K.

    This curriculum guide for a 1-semester or 1-year course in transportation provides activities that show and explain many of the occupations, devices, and systems that are related to transportation on land, water, air, and space. The guide contains competencies (task lists), student competency records, and management sheets. Management sheets,…

  10. Region-dependent absorption of faropenem shared with foscarnet, a phosphate transporter substrate, in the rat small intestine.

    PubMed

    Saitoh, Hiroshi; Sawazaki, Rinako; Oda, Masako; Kobayashi, Michiya

    2008-09-01

    Faropenem, a penem antibiotic, is orally active despite its hydrophilic nature. However, its intestinal absorption has not yet been characterised in detail. This study was undertaken to determine the factors regulating faropenem absorption using intestinal loops prepared in the rat duodenum, jejunum and terminal ileum. Faropenem disappearance was much greater than that of cefotaxime and meropenem, and faropenem disappeared more extensively from the terminal ileum than from the jejunum or duodenum. In contrast to faropenem, the disappearance of ceftibuten was much greater from the duodenum and jejunum than from the terminal ileum. As the accumulation and enzymatic degradation of faropenem was minimal in the intestinal mucosa, faropenem was considered to enter the portal vein smoothly after its disappearance from the intestinal loops. Faropenem disappearance was not significantly influenced by the presence of monocarboxylic acids, amino acids or bile acid. Dipeptides such as L-carnosine and glycylglycine slightly but significantly lowered faropenem disappearance from the terminal ileum. On the other hand, foscarnet exerted a marked inhibitory effect on faropenem disappearance, but the antiviral agent did not modulate ceftibuten absorption. The present results suggest that faropenem is in part absorbed via a phosphate transporter present in the rat small intestine. PMID:18614339

  11. Phosphate/Zinc Interaction Analysis in Two Lettuce Varieties Reveals Contrasting Effects on Biomass, Photosynthesis, and Dynamics of Pi Transport

    PubMed Central

    Bouain, Nadia; Kisko, Mushtak; Rouached, Aida; Dauzat, Myriam; Lacombe, Benoit; Belgaroui, Nibras; Ghnaya, Tahar; Davidian, Jean-Claude; Berthomieu, Pierre; Abdelly, Chedly

    2014-01-01

    Inorganic phosphate (Pi) and Zinc (Zn) are essential nutrients for normal plant growth. Interaction between these elements has been observed in many crop plants. Despite its agronomic importance, the biological significance and genetic basis of this interaction remain largely unknown. Here we examined the Pi/Zn interaction in two lettuce (Lactuca sativa) varieties, namely, “Paris Island Cos” and “Kordaat.” The effects of variation in Pi and Zn supply were assessed on biomass and photosynthesis for each variety. Paris Island Cos displayed better growth and photosynthesis compared to Kordaat under all the conditions tested. Correlation analysis was performed to determine the interconnectivity between Pi and Zn intracellular contents in both varieties. Paris Island Cos showed a strong negative correlation between the accumulation levels of Pi and Zn in shoots and roots. However, no relation was observed for Kordaat. The increase of Zn concentration in the medium causes a decrease in dynamics of Pi transport in Paris Island Cos, but not in Kordaat plants. Taken together, results revealed a contrasting behavior between the two lettuce varieties in terms of the coregulation of Pi and Zn homeostasis and provided evidence in favor of a genetic basis for the interconnection of these two elements. PMID:25025059

  12. Structural interaction with transportation and handling systems

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Problems involved in the handling and transportation of finished space vehicles from the factory to the launch site are presented, in addition to recommendations for properly accounting for in space vehicle structural design, adverse interactions during transportation. Emphasis is given to the protection of vehicle structures against those environments and loads encountered during transportation (including temporary storage) which would exceed the levels that the vehicle can safely withstand. Current practices for verifying vehicle safety are appraised, and some of the capabilities and limitations of transportation and handling systems are summarized.

  13. OsPHF1 Regulates the Plasma Membrane Localization of Low- and High-Affinity Inorganic Phosphate Transporters and Determines Inorganic Phosphate Uptake and Translocation in Rice1[W][OA

    PubMed Central

    Chen, Jieyu; Liu, Yu; Ni, Jun; Wang, Yifeng; Bai, Youhuang; Shi, Jing; Gan, Jian; Wu, Zhongchang; Wu, Ping

    2011-01-01

    PHOSPHATE TRANSPORTER TRAFFIC FACILITATOR1 (PHF1) is known to regulate the plasma membrane localization of PHT1;1, a high-affinity inorganic phosphate (Pi) transporter in Arabidopsis (Arabidopsis thaliana). OsPHF1, a rice (Oryza sativa) gene homologous to AtPHF1, was isolated and found to regulate the localization of both low- and high-affinity Pi transporters to the plasma membrane. Three OsPHF1 allelic mutants carrying one-point mutations at the fifth WD-repeat motif and two at the transmembrane helix, respectively, showed arsenate resistance and severely reduced Pi accumulation. The data indicate that mutation of OsPHF1 results in the endoplasmic reticulum retention of the low-affinity Pi transporter OsPT2 and high-affinity Pi transporter OsPT8. Mutation of OsPHF1 also reduced Pi accumulation in plants exhibiting excessive shoot Pi accumulation due to the overexpression of OsPHR2. However, the transcript level of OsPHF1 itself is not controlled by OsPHR2. Overexpression of OsPHF1 increased Pi accumulation in both roots and shoots in a solution culture with Pi-supplied condition. These results indicate that the role of OsPHF1 is unique in the localization of both low- and high-affinity Pi transporters on the plasma membrane in rice and determines Pi uptake and translocation in rice. The similar function of PHF1 required to facilitate PHT1 transit through the endoplasmic reticulum between Arabidopsis and rice provides an example of expectations from what one would deduce from sequence comparisons to extend knowledge from Arabidopsis to crops. PMID:21753117

  14. Optimization for Reduced-Fat / Low-NaCl Meat Emulsion Systems with Sea Mustard (Undaria pinnatifida) and Phosphate

    PubMed Central

    Kim, Cheon-Jei; Hwang, Ko-Eun; Song, Dong-Heon; Jeong, Tae-Jun; Kim, Hyun-Wook

    2015-01-01

    The effects of reducing fat levels from 30% to 20% and salt concentrations from 1.5% to 1.0% by partially substituting incorporated phosphate and sea mustard were investigated based on physicochemical properties of reduced-fat / low-NaCl meat emulsion systems. Cooking loss and emulsion stability, hardness, springiness, and cohesiveness for reduced-fat / low-NaCl meat emulsion systems with 20% pork back fat and 1.2% sodium chloride samples with incorporation of phosphate and sea mustard were similar to the control with 30% pork back fat and 1.5% sodium chloride. Results showed that reduced-fat / low-NaCl meat emulsion system samples containing phosphate and sea mustard had higher apparent viscosity. The results of this study show that the incorporation of phosphate and sea mustard in the formulation will successfully reduce fat and salt in the final meat products. PMID:26761874

  15. Propulsion system for research VTOL transports

    NASA Technical Reports Server (NTRS)

    Gertsma, L. W.; Zigan, S.

    1973-01-01

    In anticipation of an eventual VTOL requirement for civil aviation, NASA has been conducting studies directed toward determining and developing the technology required for a commercial VTOL transport. In this paper, the commercial transport configurations are briefly reviewed; the propulsion system specifications and components developed by the engine study contractor are presented and described; and methods for using the lift-propulsion system for aircraft attitude control are discussed.

  16. One-pot synthesis of L-Fructose using coupled multienzyme systems based on rhamnulose-1-phosphate aldolase.

    PubMed

    Franke, Dirk; Machajewski, Timothy; Hsu, Che-Chang; Wong, Chi-Huey

    2003-08-22

    Two methods have been developed for the highly efficient enzymatic synthesis of L-fructose: one is based on rhamnulose-1-phosphate aldolase and acid phosphatase using racemic glyceraldehyde and dihydroxyacetone phosphate as substrates; the other is to generate enantiomerically pure L-glyceraldehyde in situ from glycerol for the aldol reaction, using galactose oxidase catalyzed oxidation of glycerol in the presence of catalase. Using this four-enzyme system, enantiomerically pure L-fructose was obtained. Using the more expensive dihydroxyacetone phosphate, the yield was 55% after purification. PMID:12919060

  17. Electromagnetic effects on transportation systems

    SciTech Connect

    Morris, M.E.; Dinallo, M.A.

    1996-05-01

    Electronic and electrical system protection design can be used to eliminate deleterious effects from lightning, electromagnetic interference, and electrostatic discharges. Evaluation of conventional lightning protection systems using advanced computational modeling in conjunction with rocket-triggered lightning tests suggests that currently used lightning protection system design rules are inadequate and that significant improvements in best practices used for electronic and electrical system protection designs are possible. A case study of lightning induced upset and failure of a railway signal and control system is sketched.

  18. The type III transporters (PiT-1 and PiT-2) are the major sodium-dependent phosphate transporters in the mice and human brains.

    PubMed

    Inden, Masatoshi; Iriyama, Masaki; Zennami, Miho; Sekine, Shin-Ichiro; Hara, Akira; Yamada, Mitsunori; Hozumi, Isao

    2016-04-15

    PiT-1/SLC20A1 and PiT-2/SLC20A2 are members of the mammalian type-III inorganic phosphate (Pi) transporters encoded by the SLC20 genes. The broad distribution of SLC20A1 and SLC20A2 mRNAs in mammalian tissues is compatible with housekeeping maintenace of intracellular Pi homeostasis by transporting Pi from intrastitial fluid for normal cellular functions. Recently, mutations of SLC20A2 have been found in patients with idiopathic basal ganglia calcification (IBGC), also known as Fahr's disease. However, the localization of PiT-1 and PiT-2 in the normal brain has not been clarified yet. The aim of this study was to reveal the distribution of PiT-1 and PiT-2 in the mouse and human brains. As results, gene expressing analysis showed that SLC20A1 and SLC20A2 mRNAs were widely expressed throughout the mouse and human brains, although other Pi transporters encoded by SLC17 and SLC34 mRNAs were hardly detected. The region of cerebellum contained a higher level of SLC20A1 and SLC20A2 mRNAs than the other brain regions. Additionally, the cerebellum in the mouse brain contained higher levels of PiT-1 and PiT-2 than those in the other regions in the brain, respectively. The immonohistochemical studies showed that PiT-1 was recognized in neuron, astrocytes and vascular endothelial cells. Similarly to PiT-1 immunopositivity, PiT-2 was clearly recognized in these cells. These results suggest that SLC20 family plays a pivotal role in the maintenance of cellular Pi homeostasis particullary in the brain. The viewpoint is compatible with the finding that calcification in IBGC is recognized only in the brain. This provides us with a novel viewpoint to understand the basic pathophysiology of IBGC through type-III Pi transporters. PMID:26923164

  19. Systemic Analysis Approaches for Air Transportation

    NASA Technical Reports Server (NTRS)

    Conway, Sheila

    2005-01-01

    Air transportation system designers have had only limited success using traditional operations research and parametric modeling approaches in their analyses of innovations. They need a systemic methodology for modeling of safety-critical infrastructure that is comprehensive, objective, and sufficiently concrete, yet simple enough to be used with reasonable investment. The methodology must also be amenable to quantitative analysis so issues of system safety and stability can be rigorously addressed. However, air transportation has proven itself an extensive, complex system whose behavior is difficult to describe, no less predict. There is a wide range of system analysis techniques available, but some are more appropriate for certain applications than others. Specifically in the area of complex system analysis, the literature suggests that both agent-based models and network analysis techniques may be useful. This paper discusses the theoretical basis for each approach in these applications, and explores their historic and potential further use for air transportation analysis.

  20. The WIPP transportation system: Dedicated to safety

    SciTech Connect

    Ward, T.; McFadden, M.

    1993-12-01

    When developing a transportation system to transport transuranic (TRU) waste from ten widely-dispersed generator sites, the Department of Energy (DOE) recognized and addressed many challenges. Shipments of waste to the Waste Isolation Pilot Plant (WIPP) were to cover a twenty-five year period and utilize routes covering over twelve thousand miles in twenty-three states. Enhancing public safety by maximizing the payload, thus reducing the number of shipments, was the primary objective. To preclude the requirement for overweight permits, the DOE started with a total shipment weight limit of 80,000 pounds and developed an integrated transportation system consisting of a Type ``B`` package to transport the material, a lightweight tractor and trailer, stringent driver requirements, and a shipment tracking system referred to as ``TRANSCOM``.

  1. Function of the Golgi-located phosphate transporter PHT4;6 is critical for senescence-associated processes in Arabidopsis

    PubMed Central

    Hassler, Sebastian; Jung, Benjamin; Lemke, Lilia; Novák, Ondřej; Strnad, Miroslav; Martinoia, Enrico; Neuhaus, H. Ekkehard

    2016-01-01

    The phosphate transporter PHT4;6 locates to the trans-Golgi compartment, and its impaired activity causes altered intracellular phosphate compartmentation, leading to low cytosolic Pi levels, a blockage of Golgi-related processes such as protein glycosylation and hemicellulose biosynthesis, and a dwarf phenotype. However, it was unclear whether altered Pi homeostasis in pht4;6 mutants causes further cellular problems, typically associated with limited phosphate availability. Here we report that pht4;6 mutants exhibit a markedly increased disposition to induce dark-induced senescence. In control experiments, in which pht4;6 mutants and wild-type plants developed similarly, we confirmed that accelerated dark-induced senescence in mutants is not a ‘pleiotropic’ process associated with the dwarf phenotype. In fact, accelerated dark-induced senescence in pht4;6 mutants correlates strongly with increased levels of toxic NH4 + and higher sensitivity to ammonium, which probably contribute to the inability of pht4;6 mutants to recover from dark treatment. Experiments with modified levels of either salicylic acid (SA) or trans-zeatin (tZ) demonstrate that altered concentrations of these compounds in pht4;6 plants act as major cellular mediators for dark-induced senescence. This conclusion gained further support from the notion that the expression of the pht4;6 gene is, in contrast to genes coding for major phosphate importers, substantially induced by tZ. Taken together, our findings point to a critical function of PHT4;6 to control cellular phosphate levels, in particular the cytosolic Pi availability, required to energize plant primary metabolism for proper plant development. Phosphate and its allocation mediated by PHT4;6 is critical to prevent onset of dark-induced senescence. PMID:27325894

  2. TRANSIMS: Transportation analysis and simulation system

    SciTech Connect

    Smith, L.; Beckman, R.; Baggerly, K.

    1995-07-01

    This document summarizes the TRansportation ANalysis and SIMulation System (TRANSIMS) Project, the system`s major modules, and the project`s near-term plans. TRANSIMS will employ advanced computational and analytical techniques to create an integrated regional transportation systems analysis environment. The simulation environment will include a regional population of individual travelers and freight loads with travel activities and plans, whose individual interactions will be simulated on the transportation system, and whose environmental impact will be determined. We will develop an interim operational capability (IOC) for each major TRANSIMS module during the five-year program. When the IOC is ready, we will complete a specific case study to confirm the IOC features, applicability, and readiness.

  3. TRANSIMS: TRansportation ANalysis and SIMulation System

    SciTech Connect

    Smith, L.; Beckman, R.; Anson, D.; Nagel, K.; Williams, M.

    1995-08-01

    This paper summarizes the TRansportation ANalysis and SIMulation System (TRANSIMS) Project, the system`s major modules, and the project`s near-term plans. TRANSIMS will employ advanced computational and analytical techniques to create an integrated regional transportation systems analysis environment. The simulation environment will include a regional population of individual travelers and freight loads with travel activities and plans, whose individual interactions will be simulated on the transportation system, and whose environmental impact will be determined. We will develop an interim operational capability (IOC) for each major TRANSIMS module during the five-year program. When the IOC is ready, we will complete a specific case study to confirm the IOC features, applicability, and readiness.

  4. Fire and materials modeling for transportation systems

    SciTech Connect

    Skocypec, R.D.; Gritzo, L.A.; Moya, J.L.; Nicolette, V.F.; Tieszen, S.R.; Thomas, R.

    1994-10-01

    Fire is an important threat to the safety of transportation systems. Therefore, understanding the effects of fire (and its interaction with materials) on transportation systems is crucial to quantifying and mitigating the impact of fire on the safety of those systems. Research and development directed toward improving the fire safety of transportation systems must address a broad range of phenomena and technologies, including: crash dynamics, fuel dispersion, fire environment characterization, material characterization, and system/cargo thermal response modeling. In addition, if the goal of the work is an assessment and/or reduction of risk due to fires, probabilistic risk assessment technology is also required. The research currently underway at Sandia National Laboratories in each of these areas is summarized in this paper.

  5. Calcium phosphate-PEG-insulin-casein (CAPIC) particles as oral delivery systems for insulin.

    PubMed

    Morçöl, T; Nagappan, P; Nerenbaum, L; Mitchell, A; Bell, S J D

    2004-06-11

    An oral delivery system for insulin was developed and functional activity was tested in a non-obese diabetic (NOD) mice model. Calcium phosphate particles containing insulin was synthesized in the presence of PEG-3350 and modified by aggregating the particles with caseins to obtain the calcium phosphate-PEG-insulin-casein (CAPIC) oral insulin delivery system. Single doses of CAPIC formulation were tested in NOD mice under fasting or fed conditions to evaluate the glycemic activity. The blood glucose levels were monitored every 1-2h for 12h following the treatments using an ACCU CHECK blood glucose monitoring system. Orally administered and subcutaneously injected free insulin solution served as controls in the study. Based on the results obtained we propose that: (1). the biological activity of insulin is preserved in CAPIC formulation; (2). insulin in CAPIC formulations, but not the free insulin, displays a prolonged hypoglycemic effect after oral administration to diabetic mice; (3). CAPIC formulation protects insulin from degradation while passing through the acidic environment of the GI track until it is released in the less acidic environment of the intestines where it can be absorbed in its biologically active form; (4). CAPIC formulation represents a new and unique oral delivery system for insulin and other macromolecules. PMID:15158972

  6. Automatic microfluidic fluorescence-array measurement system for detecting organic phosphate.

    PubMed

    Chang, Hsing-Cheng; Lin, Jung-Chin; Lin, Shyan-Lung; Chang, I-Nan; Lin, Chern-Sheng; Chen, Shi-Yao

    2015-01-01

    In this study, an automatic microfluidic fluorescence-array measurement system is developed to detect the concentration of organic phosphate based on the luminol-hydrogen peroxide catalytic fluorescent mechanism. Not only sample quantity and cost can be reduced, but also detection time, accuracy and precision can be improved in the system. The system is composed of a CCD image module, a stepper motor with driver, a microfluidic fluorescence array, a background light elimination module, and a dynamic image-analyzed interface. The pesticides of chlorpyrifos and fenitrothion of organic phosphate are chosen as experimental samples. Only a 2.5 μ l quantity of sample is required to have a fast response time of 1.4 second. Experimental results show that the sensitivities of chlorpyrifos and fenitrothion are 1.88 V/ppm in the range of 0.166 ∼ 10 ppm with averaged error of 1.66% and 0.32 V/ppm in the range of 0.03 ∼ 10 ppm with averaged error of 1.68% respectively. The organophosphorus effective detection range of the developed system covers the legal prescription for pesticide residues. PMID:26409537

  7. 49 CFR 37.33 - Airport transportation systems.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 1 2012-10-01 2012-10-01 false Airport transportation systems. 37.33 Section 37.33 Transportation Office of the Secretary of Transportation TRANSPORTATION SERVICES FOR INDIVIDUALS WITH DISABILITIES (ADA) Applicability § 37.33 Airport transportation systems. (a)...

  8. 49 CFR 37.25 - University transportation systems.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 1 2013-10-01 2013-10-01 false University transportation systems. 37.25 Section 37.25 Transportation Office of the Secretary of Transportation TRANSPORTATION SERVICES FOR INDIVIDUALS WITH DISABILITIES (ADA) Applicability § 37.25 University transportation systems....

  9. 49 CFR 37.33 - Airport transportation systems.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false Airport transportation systems. 37.33 Section 37.33 Transportation Office of the Secretary of Transportation TRANSPORTATION SERVICES FOR INDIVIDUALS WITH DISABILITIES (ADA) Applicability § 37.33 Airport transportation systems. (a)...

  10. 49 CFR 37.33 - Airport transportation systems.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 1 2013-10-01 2013-10-01 false Airport transportation systems. 37.33 Section 37.33 Transportation Office of the Secretary of Transportation TRANSPORTATION SERVICES FOR INDIVIDUALS WITH DISABILITIES (ADA) Applicability § 37.33 Airport transportation systems. (a)...

  11. 49 CFR 37.33 - Airport transportation systems.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 1 2011-10-01 2011-10-01 false Airport transportation systems. 37.33 Section 37.33 Transportation Office of the Secretary of Transportation TRANSPORTATION SERVICES FOR INDIVIDUALS WITH DISABILITIES (ADA) Applicability § 37.33 Airport transportation systems. (a)...

  12. 49 CFR 37.25 - University transportation systems.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 1 2012-10-01 2012-10-01 false University transportation systems. 37.25 Section 37.25 Transportation Office of the Secretary of Transportation TRANSPORTATION SERVICES FOR INDIVIDUALS WITH DISABILITIES (ADA) Applicability § 37.25 University transportation systems....

  13. 49 CFR 37.25 - University transportation systems.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 1 2011-10-01 2011-10-01 false University transportation systems. 37.25 Section 37.25 Transportation Office of the Secretary of Transportation TRANSPORTATION SERVICES FOR INDIVIDUALS WITH DISABILITIES (ADA) Applicability § 37.25 University transportation systems....

  14. 49 CFR 37.25 - University transportation systems.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false University transportation systems. 37.25 Section 37.25 Transportation Office of the Secretary of Transportation TRANSPORTATION SERVICES FOR INDIVIDUALS WITH DISABILITIES (ADA) Applicability § 37.25 University transportation systems....

  15. Design of a lunar transportation system

    NASA Technical Reports Server (NTRS)

    Sankaravelu, A.; Goddard, H.; Gold, R.; Greenwell, S.; Lander, J.; Nordell, B.; Stepp, K.; Styer, M.

    1989-01-01

    The development of a good transportation infrastructure is a major requirement for the establishment of a permanent lunar base. Transportation is characterized by the technology available in a specific time frame and the need to transport personnel and cargo between Earth and Moon, and between lunar bases. In our study, attention was first focused on developing a transportation system for the first generation lunar base. As a first step, a tracked-type multipurpose lunar transportation vehicle was considered as a possible mode of transportation and a detailed study was conducted on the various aspects of the vehicle. Since the vehicle is composed of many moving parts, exposing it to the environment of the Moon, where fine dust particles are prevalent, can cause problems associated with lubrication and friction. The vehicle also posed problems concerning weight and power. Hence, several modifications were made to the above design ideas conceptually, and a Lunar Articulated Remote Transportation System (Lunar ARTS) is proposed as a more effective alternative with the following objectives: (1) minimizing the transportation of construction material and fuel from Earth or maximizing the use of the lunar material; (2) use of novel materials and light-weight structures; (3) use of new manufacturing methods and technology such as magnetic levitation using superconducting materials; and (4) innovative concepts of effectively utilizing the exotic lunar conditions, i.e., high thermal gradients, lack of atmosphere, lower gravity, etc. To achieve the above objectives of designing transportation systems from concept to operation, the project was planned in three phases: (1) conceptual design; (2) detailed analysis and synthesis; and (3) construction, testing, evaluation, and operation. In this project, both phases 1 and 2 have been carried out and work on phase 3 is in progress. In this paper, the details of the Lunar ARTS are discussed and the future work on the vehicle are

  16. Hyperspectral imaging utility for transportation systems

    NASA Astrophysics Data System (ADS)

    Bridgelall, Raj; Rafert, J. Bruce; Tolliver, Denver

    2015-03-01

    The global transportation system is massive, open, and dynamic. Existing performance and condition assessments of the complex interacting networks of roadways, bridges, railroads, pipelines, waterways, airways, and intermodal ports are expensive. Hyperspectral imaging is an emerging remote sensing technique for the non-destructive evaluation of multimodal transportation infrastructure. Unlike panchromatic, color, and infrared imaging, each layer of a hyperspectral image pixel records reflectance intensity from one of dozens or hundreds of relatively narrow wavelength bands that span a broad range of the electromagnetic spectrum. Hence, every pixel of a hyperspectral scene provides a unique spectral signature that offers new opportunities for informed decision-making in transportation systems development, operations, and maintenance. Spaceborne systems capture images of vast areas in a short period but provide lower spatial resolution than airborne systems. Practitioners use manned aircraft to achieve higher spatial and spectral resolution, but at the price of custom missions and narrow focus. The rapid size and cost reduction of unmanned aircraft systems promise a third alternative that offers hybrid benefits at affordable prices by conducting multiple parallel missions. This research formulates a theoretical framework for a pushbroom type of hyperspectral imaging system on each type of data acquisition platform. The study then applies the framework to assess the relative potential utility of hyperspectral imaging for previously proposed remote sensing applications in transportation. The authors also introduce and suggest new potential applications of hyperspectral imaging in transportation asset management, network performance evaluation, and risk assessments to enable effective and objective decision- and policy-making.

  17. Competitive immobilization of Pb in an aqueous ternary-metals system by soluble phosphates with varying pH.

    PubMed

    Zhang, Zhuo; Ren, Jie; Wang, Mei; Song, Xinlai; Zhang, Chao; Chen, Jiayu; Li, Fasheng; Guo, Guanlin

    2016-09-01

    Chemical immobilization by phosphates has been widely and successfully applied to treat Pb in wastewater and contaminated soils. Pb in wastewaters and soils, however, always coexists with other heavy metals and their competitive reactions with phosphates have not been quantitatively and systematically studied. In this approach, immobilization of Pb, Zn, and Cd by mono-, di-, and tripotassium phosphate (KH2PO4, K2HPO4, and K3PO4) was observed in the single- and ternary-metals solutions. The immobilization rates of the three metals were determined by the residual concentration. The mineral composition and structure of the precipitates were characterized by powder X-ray diffraction (XRD) analysis and scanning electron microscopy (SEM). The results indicated that competitive reaction occurred in Pb-Zn-Cd ternary system, with immobilization rates decrease of <3.6%, <78%, and <89% for Pb, Zn and Cd (molar ratios of P: metal <1), respectively, compared to single metal system. The reaction of Pb with three phosphates exhibited intense competitiveness and the phosphates had a stronger affinity for Pb when Cl(-) was added. Pb-phosphate minerals formed by KH2PO4 with the better crystalline characteristics and largest size were very stable with a low dissolution rate (<0.02%) in the solution of pH 2.88, compared to K2HPO4 and K3PO4. This study demonstrated that Pb could be firstly and effectively immobilized by phosphates in multi-metal solutions containing Pb, Zn and Cd. Moreover, the research provided the insight of the importance of phosphate with low pH (e.g. KH2PO4) and the presence of Cl(-) for more efficient immobilization of Pb in the multi-metals pollution system. PMID:27276163

  18. Not planning a sustainable transport system

    SciTech Connect

    Finnveden, Göran Åkerman, Jonas

    2014-04-01

    The overall objective of the Swedish transport policy is to ensure the economically efficient and sustainable provision of transport services for people and business throughout the country. More specifically, the transport sector shall, among other things, contribute to the achievement of environmental quality objectives in which the development of the transport system plays an important role in the achievement of the objectives. The aim of this study is to analyse if current transport planning supports this policy. This is done by analysing two recent cases: the National Infrastructure Plan 2010–2021, and the planning of Bypass Stockholm, a major road investment. Our results show that the plans are in conflict with several of the environmental quality objectives. Another interesting aspect of the planning processes is that the long-term climate goals are not included in the planning processes, neither as a clear goal nor as factor that will influence future transport systems. In this way, the long-term sustainability aspects are not present in the planning. We conclude that the two cases do not contribute to a sustainable transport system. Thus, several changes must be made in the processes, including putting up clear targets for emissions. Also, the methodology for the environmental assessments needs to be further developed and discussed. - Highlights: • Two cases are studied to analyse if current planning supports a sustainable transport system. • Results show that the plans are in conflict with several of the environmental quality objectives. • Long-term climate goals are not included in the planning processes. • Current practices do not contribute to a sustainable planning processes. • Methodology and process for environmental assessments must be further developed and discussed.

  19. Human Transportation System (HTS) study, volume 1

    NASA Technical Reports Server (NTRS)

    Lance, N.; Geyer, M. S.; Gaunce, M. T.

    1993-01-01

    Work completed under the Human Transportation System Study is summarized. This study was conducted by the New Initiatives Office at JSC with the technical support of Boeing, General Dynamics, Lockheed, McDonnell-Douglas, Martin Marietta, and Rockwell. The study was designed to generate information on determining the appropriate path to follow for new system development to meet the Nation's space transportation needs. The study evaluates 18 transportation architecture options using a parametric set of mission requirements. These options include use of current systems as well as proposed systems to assess the impact of various considerations, such as the cost of alternate access, or the benefit of separating people and cargo. The architecture options are compared to each other with six measurable evaluation criteria or attributes. They are the following: funding profile, human safety, probability of mission success, architecture cost risk, launch schedule confidence, and environmental impact. Values for these attributes are presented for the architecture options, with pertinent conclusions and recommendations.

  20. Human Transportation System (HTS) study, volume 1

    NASA Astrophysics Data System (ADS)

    Lance, N.; Geyer, M. S.; Gaunce, M. T.

    1993-10-01

    Work completed under the Human Transportation System Study is summarized. This study was conducted by the New Initiatives Office at JSC with the technical support of Boeing, General Dynamics, Lockheed, McDonnell-Douglas, Martin Marietta, and Rockwell. The study was designed to generate information on determining the appropriate path to follow for new system development to meet the Nation's space transportation needs. The study evaluates 18 transportation architecture options using a parametric set of mission requirements. These options include use of current systems as well as proposed systems to assess the impact of various considerations, such as the cost of alternate access, or the benefit of separating people and cargo. The architecture options are compared to each other with six measurable evaluation criteria or attributes. They are the following: funding profile, human safety, probability of mission success, architecture cost risk, launch schedule confidence, and environmental impact. Values for these attributes are presented for the architecture options, with pertinent conclusions and recommendations.

  1. Human Transportation System (HTS) study: Executive summary

    NASA Astrophysics Data System (ADS)

    Lance, N.; Geyer, M. S.; Gaunce, M. T.

    1993-10-01

    Work completed under the Human Transportation System Study is summarized. This study was conducted by the New Initiatives Office at JSC with the technical support of Boeing, General Dynamics, Lockheed, McDonnell-Douglas, Martin Marietta, and Rockwell. The study was designed to generate information on determining the appropriate path to follow for new system development to meet the Nation's space transportation needs. The study evaluates 18 transportation architecture options using a parametric set of mission requirements. These options include use of current systems as well as proposed systems to assess the impact of various considerations, such as the cost of alternate access, or the benefit of separating people and cargo. The architecture options are compared to each other with six measurable evaluation criteria or attributes. They are the following: funding profile, human safety, probability of mission success, architecture cost risk, launch schedule confidence, and environmental impact. Values for these attributes are presented for the architecture options, with pertinent conclusions and recommendations.

  2. Human Transportation System (HTS) study: Executive summary

    NASA Technical Reports Server (NTRS)

    Lance, N.; Geyer, M. S.; Gaunce, M. T.

    1993-01-01

    Work completed under the Human Transportation System Study is summarized. This study was conducted by the New Initiatives Office at JSC with the technical support of Boeing, General Dynamics, Lockheed, McDonnell-Douglas, Martin Marietta, and Rockwell. The study was designed to generate information on determining the appropriate path to follow for new system development to meet the Nation's space transportation needs. The study evaluates 18 transportation architecture options using a parametric set of mission requirements. These options include use of current systems as well as proposed systems to assess the impact of various considerations, such as the cost of alternate access, or the benefit of separating people and cargo. The architecture options are compared to each other with six measurable evaluation criteria or attributes. They are the following: funding profile, human safety, probability of mission success, architecture cost risk, launch schedule confidence, and environmental impact. Values for these attributes are presented for the architecture options, with pertinent conclusions and recommendations.

  3. NASA's Advanced Space Transportation System launch vehicles

    NASA Technical Reports Server (NTRS)

    Branscome, Darrell R.

    1990-01-01

    An account is given of NASA's Advanced Space Transportation System plans, with a view to the support systems that must be evolved in order to implement such long-term mission requirements; these encompass space-based infrastructure for orbital transfer operations between LEO and GEO, and for operations from LEO to lunar orbit and to Mars. These mission requirements are addressed by the NASA Civil Needs Data Base in order to promote multiple applications. The requisite near-term lift capacity to LEO could be achieved through the development of the Shuttle-derived, unmanned Shuttle-C cargo launch system. Longer-term transportation studies are concerned with the Next Manned Transportation System and Space Transfer Vehicles.

  4. Transportable Vitrification System Demonstration on Mixed Waste

    SciTech Connect

    Zamecnik, J.R.; Whitehouse, J.C.; Wilson, C.N.; Van Ryn, F.R.

    1998-01-01

    This paper describes preliminary results from the first demonstration of the Transportable Vitrification System (TVS) on actual mixed waste. The TVS is a fully integrated, transportable system for the treatment of mixed and low-level radioactive wastes. The demonstration was conducted at Oak Ridge`s East Tennessee Technology Park (ETTP), formerly known as the K-25 site. The purpose of the demonstration was to show that mixed wastes could be vitrified safely on a `field` scale using joule-heated melter technology and obtain information on system performance, waste form durability, air emissions, and costs.

  5. Advanced secondary power system for transport aircraft

    NASA Technical Reports Server (NTRS)

    Hoffman, A. C.; Hansen, I. G.; Beach, R. F.; Plencner, R. M.; Dengler, R. P.; Jefferies, K. S.; Frye, R. J.

    1985-01-01

    A concept for an advanced aircraft power system was identified that uses 20-kHz, 440-V, sin-wave power distribution. This system was integrated with an electrically powered flight control system and with other aircraft systems requiring secondary power. The resulting all-electric secondary power configuration reduced the empty weight of a modern 200-passenger, twin-engine transport by 10 percent and the mission fuel by 9 percent.

  6. Monte Carlo Nucleon Meson Transport Code System.

    Energy Science and Technology Software Center (ESTSC)

    2000-11-17

    Version 00 NMTC/JAERI97 is an upgraded version of the code system NMTC/JAERI, which was developed in 1982 at JAERI and is based on the CCC-161/NMTC code system. NMTC/JAERI97 simulates high energy nuclear reactions and nucleon-meson transport processes.

  7. Alternative battery systems for transportation uses

    ScienceCinema

    Michael Thackeray

    2013-06-05

    Argonne Distinguished Fellow Michael Thackeray highlights the need for alternative battery systems for transportation uses. Such systems will not only need to be smaller, lighter and more energy dense, but also able to make electric vehicles more competitive with internal combustion engine vehicles.

  8. Alternative battery systems for transportation uses

    SciTech Connect

    Michael Thackeray

    2012-07-25

    Argonne Distinguished Fellow Michael Thackeray highlights the need for alternative battery systems for transportation uses. Such systems will not only need to be smaller, lighter and more energy dense, but also able to make electric vehicles more competitive with internal combustion engine vehicles.

  9. The Integrated Air Transportation System Evaluation Tool

    NASA Technical Reports Server (NTRS)

    Wingrove, Earl R., III; Hees, Jing; Villani, James A.; Yackovetsky, Robert E. (Technical Monitor)

    2002-01-01

    Throughout U.S. history, our nation has generally enjoyed exceptional economic growth, driven in part by transportation advancements. Looking forward 25 years, when the national highway and skyway systems are saturated, the nation faces new challenges in creating transportation-driven economic growth and wealth. To meet the national requirement for an improved air traffic management system, NASA developed the goal of tripling throughput over the next 20 years, in all weather conditions while maintaining safety. Analysis of the throughput goal has primarily focused on major airline operations, primarily through the hub and spoke system.However, many suggested concepts to increase throughput may operate outside the hub and spoke system. Examples of such concepts include the Small Aircraft Transportation System, civil tiltrotor, and improved rotorcraft. Proper assessment of the potential contribution of these technologies to the domestic air transportation system requires a modeling capability that includes the country's numerous smaller airports, acting as a fundamental component of the National Air space System, and the demand for such concepts and technologies. Under this task for NASA, the Logistics Management Institute developed higher fidelity demand models that capture the interdependence of short-haul air travel with other transportation modes and explicitly consider the costs of commercial air and other transport modes. To accomplish this work, we generated forecasts of the distribution of general aviation based aircraft and GA itinerant operations at each of nearly 3.000 airport based on changes in economic conditions and demographic trends. We also built modules that estimate the demand for travel by different modes, particularly auto, commercial air, and GA. We examined GA demand from two perspectives: top-down and bottom-up, described in detail.

  10. A Robust Scalable Transportation System Concept

    NASA Technical Reports Server (NTRS)

    Hahn, Andrew; DeLaurentis, Daniel

    2006-01-01

    This report documents the 2005 Revolutionary System Concept for Aeronautics (RSCA) study entitled "A Robust, Scalable Transportation System Concept". The objective of the study was to generate, at a high-level of abstraction, characteristics of a new concept for the National Airspace System, or the new NAS, under which transportation goals such as increased throughput, delay reduction, and improved robustness could be realized. Since such an objective can be overwhelmingly complex if pursued at the lowest levels of detail, instead a System-of-Systems (SoS) approach was adopted to model alternative air transportation architectures at a high level. The SoS approach allows the consideration of not only the technical aspects of the NAS", but also incorporates policy, socio-economic, and alternative transportation system considerations into one architecture. While the representations of the individual systems are basic, the higher level approach allows for ways to optimize the SoS at the network level, determining the best topology (i.e. configuration of nodes and links). The final product (concept) is a set of rules of behavior and network structure that not only satisfies national transportation goals, but represents the high impact rules that accomplish those goals by getting the agents to "do the right thing" naturally. The novel combination of Agent Based Modeling and Network Theory provides the core analysis methodology in the System-of-Systems approach. Our method of approach is non-deterministic which means, fundamentally, it asks and answers different questions than deterministic models. The nondeterministic method is necessary primarily due to our marriage of human systems with technological ones in a partially unknown set of future worlds. Our goal is to understand and simulate how the SoS, human and technological components combined, evolve.

  11. Mars transportation system - Architecture trade study

    NASA Astrophysics Data System (ADS)

    Walton, Lewis A.; Malloy, John D.

    1992-07-01

    An advanced Mars base resupply transportation system utilizing nuclear thermal rockets, a split/sprint architecture, and conjunction class trajectories for the manned flight segments was studied to determine the impact of engine characteristics other than specific impulse. High engine thrust-to-weight ratios were found to offer significant performance improvements and engine clustering and shielding strategies were found to interrelate to the engine thrust-to-weight ratio in a complex manner. Performance tradeoffs of alternate abort mode and engine disposal strategies were assessed. The significant benefits of the use of indigenous Martian materials to support the transportation system were quantified.

  12. Acoustic system for material transport

    NASA Technical Reports Server (NTRS)

    Barmatz, M. B.; Trinh, E. H.; Wang, T. G.; Elleman, D. D.; Jacobi, N. (Inventor)

    1983-01-01

    An object within a chamber is acoustically moved by applying wavelengths of different modes to the chamber to move the object between pressure wells formed by the modes. In one system, the object is placed in one end of the chamber while a resonant mode, applied along the length of the chamber, produces a pressure well at the location. The frequency is then switched to a second mode that produces a pressure well at the center of the chamber, to draw the object. When the object reaches the second pressure well and is still traveling towards the second end of the chamber, the acoustic frequency is again shifted to a third mode (which may equal the first model) that has a pressure well in the second end portion of the chamber, to draw the object. A heat source may be located near the second end of the chamber to heat the sample, and after the sample is heated it can be cooled by moving it in a corresponding manner back to the first end of the chamber. The transducers for levitating and moving the object may be all located at the cool first end of the chamber.

  13. The Secure, Transportable, Autonomous Reactor System

    SciTech Connect

    Brown, N.W.; Hassberger, J.A.; Smith, C.; Carelli, M.; Greenspan, E.; Peddicord, K.L.; Stroh, K.; Wade, D.C.; Hill, R.N.

    1999-05-27

    The Secure, Transportable, Autonomous Reactor (STAR) system is a development architecture for implementing a small nuclear power system, specifically aimed at meeting the growing energy needs of much of the developing world. It simultaneously provides very high standards for safety, proliferation resistance, ease and economy of installation, operation, and ultimate disposition. The STAR system accomplishes these objectives through a combination of modular design, factory manufacture, long lifetime without refueling, autonomous control, and high reliability.

  14. Phosphate salts

    MedlinePlus

    ... taken by mouth or used as enemas. Indigestion. Aluminum phosphate and calcium phosphate are FDA-permitted ingredients ... Phosphate salts containing sodium, potassium, aluminum, or calcium are LIKELY SAFE for most people when taken by mouth short-term, when sodium phosphate is inserted into the ...

  15. A Mars/phobos Transportation System

    NASA Technical Reports Server (NTRS)

    1989-01-01

    A transportation system will be necessary to support construction and operation of bases on Phobos and Mars beginning in the year 2020 or later. An approach to defining a network of vehicles and the types of vehicles which may be used in the system are presented. The network will provide a convenient, integrated means for transporting robotically constructed bases to Phobos and Mars. All the technology needed for the current plan is expected to be available for use at the projected date of cargo departure from the Earth system. The modular design of the transportation system provides easily implemented contingency plans, so that difficulties with any one vehicle will have a minimal effect on the progress of the total mission. The transportation network proposed consists of orbital vehicles and atmospheric entry vehicles. Initially, only orbital vehicles will participate in the robotic construction phase of the Phobos base. The Interplanetary Transfer Vehicle (ITV) will carry the base and construction equipment to Phobos where the Orbital Maneuvering Vehicles (OMV's) will participate in the initial construction of the base. When the Mars base is ready to be sent, one or more ITV's will be used to transport the atmospheric entry vehicles from Earth. These atmospheric vehicles are the One Way Landers (OWL's) and the Ascent/Descent Vehicles (ADV's). They will be used to carry the base components and/or construction equipment. The OMV's and the Orbital Transfer Vehicles (OTV's) will assist in carrying the atmospheric entry vehicles to low Martian orbit where the OWL's or ADV's will descent to the planet surface. The ADV's were proposed to accommodate expansion of the system. Additionally, a smaller version of the ADV class is capable of transporting personnel between Mars and Phobos.

  16. Transportation systems analyses. Volume 1: Executive summary

    NASA Astrophysics Data System (ADS)

    1992-11-01

    The principal objective is to accomplish a systems engineering assessment of the nation's space transportation infrastructure. This analysis addresses the necessary elements to perform crew delivery and return, cargo transfer, cargo delivery and return, payload servicing, and the exploration of the Moon and Mars. Specific elements analyzed, but not limited to, include: the Space Exploration Initiative (SEI), the National Launch System (NLS), the current expendable launch vehicle (ELV) fleet, ground facilities, the Space Station Freedom (SSF), and other civil, military and commercial payloads. The performance of this study entails maintaining a broad perspective on the large number of transportation elements that could potentially comprise the U.S. space infrastructure over the next several decades. To perform this systems evaluation, top-level trade studies are conducted to enhance our understanding of the relationship between elements of the infrastructure. This broad 'infrastructure-level perspective' permits the identification of preferred infrastructures. Sensitivity analyses are performed to assure the credibility and usefulness of study results. Conceptual studies of transportation elements contribute to the systems approach by identifying elements (such as ETO node and transfer/excursion vehicles) needed in current and planned transportation systems. These studies are also a mechanism to integrate the results of relevant parallel studies.

  17. Accumulation of glucose 6-phosphate or fructose 6-phosphate is responsible for destabilization of glucose transporter mRNA in Escherichia coli.

    PubMed

    Morita, Teppei; El-Kazzaz, Waleed; Tanaka, Yuya; Inada, Toshifumi; Aiba, Hiroji

    2003-05-01

    Previously we found that a mutation in either pgi or pfkA, encoding phosphoglucose isomerase or phosphofructokinase A, respectively, facilitates degradation of the ptsG mRNA in an RNase E-dependent manner in Escherichia coli (1). In this study, we examined the effects of a series of glycolytic genes on the degradation of ptsG mRNA and how the mutations destabilize the ptsG mRNA. The conditional lethal mutation ts8 in fda, encoding fructose-1,6-P(2) aldolase just downstream of pfkA in the glycolytic pathway, caused the destabilization of ptsG mRNA at the nonpermissive temperature. Mutations in any other gene did not destabilize the ptsG mRNA; rather, they reduced the ptsG transcription mainly by affecting the cAMP level. The rapid degradation of ptsG mRNA in mutant strains was completely dependent upon the presence of glucose or any one of its compounds, which enter the Embden-Meyerhof glycolytic pathway before the block points. A significant increase in the intracellular glucose-6-P level was observed in the presence of glucose in the pgi strain. An overexpression of glucose-6-phosphate dehydrogenase eliminated both the accumulation and the degradation of ptsG mRNA in the pgi strain. In addition, accumulation of fructose-6-P led to the rapid degradation of ptsG mRNA in a pgi pfkA mutant strain lacking glucose-6-P. We conclude that the RNase E-dependent destabilization of ptsG mRNA occurs in response to accumulation of glucose-6-P or fructose-6-P. PMID:12578824

  18. Calcium phosphate ceramic systems in growth factor and drug delivery for bone tissue engineering: A review

    PubMed Central

    Bose, Susmita; Tarafder, Solaiman

    2012-01-01

    Calcium phosphates (CaPs) are the most widely used bone substitutes in bone tissue engineering due to their compositional similarities to bone mineral and excellent biocompatibility. In recent years, CaPs, especially hydroxyapatite and tricalcium phosphate, have attracted significant interest in simultaneous use as bone substitute and drug delivery vehicle, adding a new dimension to their application. CaPs are more biocompatible than many other ceramic and inorganic nanoparticles. Their biocompatibility and variable stoichiometry, thus surface charge density, functionality, and dissolution properties, make them suitable for both drug and growth factor delivery. CaP matrices and scaffolds have been reported to act as delivery vehicles for growth factors and drugs in bone tissue engineering. Local drug delivery in musculoskeletal disorder treatments can address some of the critical issues more effectively and efficiently than the systemic delivery. CaPs are used as coatings on metallic implants, CaP cements, and custom designed scaffolds to treat musculoskeletal disorders. This review highlights some of the current drug and growth factor delivery approaches and critical issues using CaP particles, coatings, cements, and scaffolds towards orthopedic and dental applications. PMID:22127225

  19. Phosphate control on the Th/U variations in ordinary chondrites: Improving solar system abundances

    NASA Astrophysics Data System (ADS)

    Goreva, J. S.; Burnett, D. S.

    2001-01-01

    Isotope dilution thorium and uranium analyses by inductively-coupled plasma mass spectrometry of 12 samples of Harleton (L6) show a much larger scatter than was previously observed in equilibrated ordinary chondrites. Th/U linearly correlates with 1/U in Harleton and in the total equilibrated ordinary chondrite data set as well. Such a correlation suggests a two component mixture and this trend can be quantitatively modeled as reflecting variations in the mixing ratio between two phosphate phases: chlorapatite and merrillite. The major effect is due to apatite variations, which strongly control the whole rock U concentrations. Phosphorous variations will tend to destroy the Th/U vs. 1/U correlation, and measured P concentrations on exactly the same samples as U and Th show a factor of 3 range. It appears that the P variations are compensated by inverse variations in U (a dilution effect) to preserve the Th/U vs. 1/U correlation. Because variations in whole rock Th/U are consequences of phosphate sampling, a weighted average of high accuracy Th/U measurements in equilibrated ordinary chondrites should converge to a significantly improved average solar system Th/U. Our best estimate of this ratio is 3.53 with ?mean = 0.10.

  20. Ion transport membrane module and vessel system

    DOEpatents

    Stein, VanEric Edward; Carolan, Michael Francis; Chen, Christopher M.; Armstrong, Phillip Andrew; Wahle, Harold W.; Ohrn, Theodore R.; Kneidel, Kurt E.; Rackers, Keith Gerard; Blake, James Erik; Nataraj, Shankar; van Doorn, Rene Hendrik Elias; Wilson, Merrill Anderson

    2008-02-26

    An ion transport membrane system comprising (a) a pressure vessel having an interior, an exterior, an inlet, and an outlet; (b) a plurality of planar ion transport membrane modules disposed in the interior of the pressure vessel and arranged in series, each membrane module comprising mixed metal oxide ceramic material and having an interior region and an exterior region, wherein any inlet and any outlet of the pressure vessel are in flow communication with exterior regions of the membrane modules; and (c) one or more gas manifolds in flow communication with interior regions of the membrane modules and with the exterior of the pressure vessel.The ion transport membrane system may be utilized in a gas separation device to recover oxygen from an oxygen-containing gas or as an oxidation reactor to oxidize compounds in a feed gas stream by oxygen permeated through the mixed metal oxide ceramic material of the membrane modules.

  1. Ion transport membrane module and vessel system

    DOEpatents

    Stein, VanEric Edward; Carolan, Michael Francis; Chen, Christopher M.; Armstrong, Phillip Andrew; Wahle, Harold W.; Ohrn, Theodore R.; Kneidel, Kurt E.; Rackers, Keith Gerard; Blake, James Erik; Nataraj, Shankar; van Doorn, Rene Hendrik Elias; Wilson, Merrill Anderson

    2007-02-20

    An ion transport membrane system comprising (a) a pressure vessel having an interior, an exterior, an inlet, and an outlet; (b) a plurality of planar ion transport membrane modules disposed in the interior of the pressure vessel and arranged in series, each membrane module comprising mixed metal oxide ceramic material and having an interior region and an exterior region, wherein any inlet and any outlet of the pressure vessel are in flow communication with exterior regions of the membrane modules; and (c) one or more gas manifolds in flow communication with interior regions of the membrane modules and with the exterior of the pressure vessel. The ion transport membrane system may be utilized in a gas separation device to recover oxygen from an oxygen-containing gas or as an oxidation reactor to oxidize compounds in a feed gas stream by oxygen permeated through the mixed metal oxide ceramic material of the membrane modules.

  2. Ion transport membrane module and vessel system

    DOEpatents

    Stein, VanEric Edward; Carolan, Michael Francis; Chen, Christopher M.; Armstrong, Phillip Andrew; Wahle, Harold W.; Ohrn, Theodore R.; Kneidel, Kurt E.; Rackers, Keith Gerard; Blake, James Erik; Nataraj, Shankar; Van Doorn, Rene Hendrik Elias; Wilson, Merrill Anderson

    2012-02-14

    An ion transport membrane system comprising (a) a pressure vessel having an interior, an exterior, an inlet, and an outlet; (b) a plurality of planar ion transport membrane modules disposed in the interior of the pressure vessel and arranged in series, each membrane module comprising mixed metal oxide ceramic material and having an interior region and an exterior region, wherein any inlet and any outlet of the pressure vessel are in flow communication with exterior regions of the membrane modules; and (c) one or more gas manifolds in flow communication with interior regions of the membrane modules and with the exterior of the pressure vessel. The ion transport membrane system may be utilized in a gas separation device to recover oxygen from an oxygen-containing gas or as an oxidation reactor to oxidize compounds in a feed gas stream by oxygen permeated through the mixed metal oxide ceramic material of the membrane modules.

  3. Crew Transportation System Design Reference Missions

    NASA Technical Reports Server (NTRS)

    Mango, Edward J.

    2015-01-01

    Contains summaries of potential design reference mission goals for systems to transport humans to andfrom low Earth orbit (LEO) for the Commercial Crew Program. The purpose of this document is to describe Design Reference Missions (DRMs) representative of the end-to-end Crew Transportation System (CTS) framework envisioned to successfully execute commercial crew transportation to orbital destinations. The initial CTS architecture will likely be optimized to support NASA crew and NASA-sponsored crew rotation missions to the ISS, but consideration may be given in this design phase to allow for modifications in order to accomplish other commercial missions in the future. With the exception of NASA’s mission to the ISS, the remaining commercial DRMs are notional. Any decision to design or scar the CTS for these additional non-NASA missions is completely up to the Commercial Provider. As NASA’s mission needs evolve over time, this document will be periodically updated to reflect those needs.

  4. Low energy beam transport system developments

    NASA Astrophysics Data System (ADS)

    Dudnikov, V.; Han, B.; Stockli, M.; Welton, R.; Dudnikova, G.

    2015-04-01

    For high brightness beam production it is important to preserve the brightness in the low energy beam transport system (LEBT) used to transport and match the ion beams to the next stage of acceleration, usually an RFQ. While electrostatic focusing can be problematic for high current beam transport, reliable electrostatic LEBT operation has been demonstrated with H- beams up to 60 mA. Now, however, it is commonly accepted that an optimal LEBT for high current accelerator applications consists of focusing solenoids with space charge compensation. Two-solenoid LEBTs are successfully used for high current (>100 mA) proton beam transport. Preservation of low emittances (~0.15 π mm-mrad) requires the addition of a heavy gas (Xe, Kr), which causes ~5% of proton loss in a 1 m long LEBT. Similar Xe densities would be required to preserve low emittances of H- beams, but such gas densities cause unacceptably high H- beam losses. A short LEBT with only one short solenoid, movable for RFQ matching, can be used for reduced negative ion stripping. A strong electrostatic-focusing LEBT has been successfully adopted for transport of high current H- beams in the SNS Front End. Some modifications of such electrostatic LEBTs are expected to improve the reliable transport of intense positive and negative ion beams without greatly degrading their low emittances. We concentrate on processes that determine the beam brightness degradation and on their prevention. Proposed improvements to the SNS electrostatic LEBT are discussed.

  5. In vitro degradation and cytocompatibility of dicalcium phosphate dihydrate cements prepared using the monocalcium phosphate monohydrate/hydroxyapatite system reveals rapid conversion to HA as a key mechanism.

    PubMed

    Alge, Daniel L; Goebel, W Scott; Chu, Tien-Min Gabriel

    2012-04-01

    We previously showed that dicalcium phosphate dihydrate (DCPD) cements can be prepared using monocalcium phosphate monohydrate (MCPM) and hydroxyapatite (HA). In this study, we have characterized the degradation properties and biocompatibility of these novel cements. To study the degradation properties, cements were prepared using MCPM:HA molar ratios of 4:1, 2:1, 2:3, and 2:5. Degradation was evaluated in vitro by static soaking in PBS, and changes in pH, mass, compressive strength, and composition were monitored. Conversion of DCPD to HA was noted in the 4:1 group, which initially consisted of pure DCPD. However, the 2:1 group, which initially consisted of DCPD and an intermediate amount of unreacted HA, underwent rapid conversion to HA associated with significantly greater pH drop and mass loss as well as a complete loss of mechanical integrity. On the basis of these results, we directly compared the cytocompatibility of 2:1 MCPM:HA cements to DCPD cements prepared with an equivalent percent molar excess of β-tricalcium phosphate (β-TCP) using an in vitro cell viability assay. Viability of cells co-cultured with 2:1 MCPM:HA cements was significantly reduced after just 48 h, while viability of cells cultured with the β-TCP-based cements was no different from control cells. In conclusion, this study demonstrates that conversion to HA plays an important role in the degradation of DCPD cements prepared with the MCPM/HA system, affecting both physical properties and cytocompatibility. These results could have important clinical implications for MCPM/HA cements. PMID:22323239

  6. Heat transport system, method and material

    DOEpatents

    Musinski, Donald L.

    1987-01-01

    A heat transport system, method and composite material in which a plurality of hollow spherical shells or microspheres having an outside diameter of less than or equal to 500 microns are encapsulated or embedded within a bulk material. Each shell has captured therein a volatile working fluid, such that each shell operates as a microsized heat pipe for conducting heat through the composite structure.

  7. PARTS: (Plasma Accelerated Reusable Transport System)

    NASA Astrophysics Data System (ADS)

    Aherne, Michael; Davis, Phil; England, Matt; Gustavsson, Jake; Pankow, Steve; Sampaio, Chere; Savella, Phil

    2002-01-01

    The Plasma Accelerated Reusable Transport System (PARTS) is an unmanned cargo shuttle intended to ferry large payloads to and from Martian orbit using a highly efficient VAriable Specific Impulse Magnetoplasma Rocket (VASIMR). The design of PARTS focuses on balancing cost and minimizing transit time for a chosen payload consisting of vehicles, satellites, and other components provided by interested parties.

  8. Tomorrows' Air Transportation System Breakout Series Report

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The purpose of this presentation is to discuss tomorrow's air transportation system. Section of this presentation includes: chair comments; other general comments; surface congestion alleviation; runway productivity; enhanced arrival/departure tools; integrated airspace decision support tools; national traffic flow management, runway independent operations; ATM TFM weather; and terminal weather.

  9. Transportation systems analyses: Volume 1: Executive Summary

    NASA Astrophysics Data System (ADS)

    1993-05-01

    The principal objective of this study is to accomplish a systems engineering assessment of the nation's space transportation infrastructure. This analysis addresses the necessary elements to perform man delivery and return, cargo transfer, cargo delivery, payload servicing, and the exploration of the Moon and Mars. Specific elements analyzed, but not limited to, include the Space Exploration Initiative (SEI), the National Launch System (NLS), the current expendable launch vehicle (ELV) fleet, ground facilities, the Space Station Freedom (SSF), and other civil, military and commercial payloads. The performance of this study entails maintaining a broad perspective on the large number of transportation elements that could potentially comprise the U.S. space infrastructure over the next several decades. To perform this systems evaluation, top-level trade studies are conducted to enhance our understanding of the relationships between elements of the infrastructure. This broad 'infrastructure-level perspective' permits the identification of preferred infrastructures. Sensitivity analyses are performed to assure the credibility and usefulness of study results. This executive summary of the transportation systems analyses (TSM) semi-annual report addresses the SSF logistics resupply. Our analysis parallels the ongoing NASA SSF redesign effort. Therefore, there could be no SSF design to drive our logistics analysis. Consequently, the analysis attempted to bound the reasonable SSF design possibilities (and the subsequent transportation implications). No other strategy really exists until after a final decision is rendered on the SSF configuration.

  10. Future space transportation systems analysis study. Phase 1 extension: Transportation systems reference data, volume 2

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Transportation mass requirements are developed for various mission and transportation modes based on vehicle systems sized to fit the exact needs of each mission. The parametric data used to derive the mass requirements for each mission and transportation mode are presented to enable accommodation of possible changes in mode options or payload definitions. The vehicle sizing and functional requirements used to derive the parametric data are described.

  11. DTS: the NOAO Data Transport System

    NASA Astrophysics Data System (ADS)

    Fitzpatrick, Michael J.

    2010-07-01

    The Data Transport System (DTS) provides automated, reliable, high-throughput data transfer between the telescopes, archives and pipeline processing systems used by the NOAO centers in the Northern and Southern hemispheres. DTS is implemented using an XML-RPC1 architecture to eliminate the need for persistent network connections between the sites, allowing each site to provide or consume services within the network only as needed. This architecture also permits remote control and monitoring of each site, and for language-independent client applications (e.g. a web interface to display transfer status or a compiled task to queue data for transport which is more tightly coupled with the acquisition system being used). The resulting system is a highly multi-threaded distributed application able to span a wide range of network environments and operational uses.

  12. Biological application of micro-electro mechanical systems microelectrode array sensors for direct measurement of phosphate in the enhanced biological phosphorous removal process.

    PubMed

    Lee, Woo Hyoung; Lee, Jin-Hwan; Bishop, Paul L; Papautsky, Ian

    2009-08-01

    The determination of phosphate has been of great importance in the fields of clinical, environmental, and horticultural analysis for over three decades. New cobalt-based micro-electro mechanical systems (MEMS) microelectrode array (MEA) sensors for direct measurement of phosphate in small environmental samples, such as microbial aggregates, has been introduced and applied here for in situ measurement of phosphate within activated sludge flocs in the enhanced biological phosphorus removal process. The MEMS technologies offer the advantages of accurate fabrication methods, reduced complexity of the fabrication process, mass production, low cost, and increased reliability. Well-defined phosphate profiles across the flocs were observed under anaerobic conditions, during which, phosphate was released from the flocs, using the MEMS MEA sensor. The microprofiles were compared with the microprofiles measured using conventional phosphate microelectrodes. The developed MEMS MEA sensors were useful tools for the in situ measurement of phosphate in small aggregates. PMID:19774851

  13. Fireworthiness of transport aircraft interior systems

    NASA Technical Reports Server (NTRS)

    Parker, J. A.; Kourtides, D. A.

    1982-01-01

    The fire worthiness of air transport interiors was evaluated. The effect of interior systems on the survival of passengers and crew in an uncontrolled transport aircraft fire is addressed. Modification of aircraft interior subsystem components which provide improvements in aircraft fire safety are examined. Three specific subsystem components, interior panels, seats and windows, offer the most immediate and highest payoff by modifying interior materials of existing aircrafts. It is shown that the new materials modifications reduce the fire hazards because of significant reduction in their characteristic flame spread, heat release, and smoke and toxic gas emissions.

  14. Space transportation systems for the future

    NASA Technical Reports Server (NTRS)

    Lee, T. J.

    1988-01-01

    A summary of the potential requirements, proposed configurations, inherent development problems, and technologies to be considered for future space transportation systems is presented. Such systems will include the improved Space Shuttle, new and derivative cargo launch vehicles, new propulsion systems, orbital transfer and maneuvering vehicles, and a second-generation Space Shuttle. It is concluded that more efficient and capable systems can be developed by placing strong emphasis on high reliability, safety, and improved ground and flight operations. These improvements can result from the introduction of advanced technologies and vehicles designed for operations and maintainability with the flexibility to adapt to mission needs.

  15. The Palm Desert Renewable Hydrogen Transportation System

    SciTech Connect

    Lehman, P.

    1996-10-01

    The present paper describes, for purposes of the Department of Energy (DoE) Hydrogen Program Review, Schatz Energy Research Center (SERC) progress on the Palm Desert Renewable Hydrogen Transportation System Project for the period January through June 1996. This period represents the first six months of the three year project. The estimated cost over three years is $3.9M, $1.859M of which is funded by the DoE ($600 k for fiscal year 1996). The goal of the Palm Desert Project is to develop a clean and sustainable transportation system for a community. The project will demonstrate the practical utility of hydrogen as a transportation fuel and proton exchange membrane (PEM) fuel cells as vehicle power plants. This transportation system will be developed in the City of Palm Desert in southern California and will include a fleet of 8 fuel cell powered vehicles, solar and wind powered hydrogen generating facilities, a consumer-ready refueling station, and a service infrastructure. The system holds the promise of a clean environment and an energy supply that is predictable, domestic, safe, and abundant. During, the first part of 1996 SERC has nearly completed building a fuel cell powered personal utility vehicle, which features an upgraded safety and computer system; they have designed and built a test bench that is able to mimic golf cart loads and test fuel cell system auxiliary components; they have begun the design of the solar hydrogen generating station; they have worked with Sandia National Laboratory on an advanced metal hydride storage system; they have increased the power density of the SERC fuel cell by as much as 50%; and they have reached out to the rest of the world with a new fact sheet, world wide web pages, a press release, video footage for a television program. and instruction within the community.

  16. Liners for ion transport membrane systems

    DOEpatents

    Carolan, Michael Francis; Miller, Christopher Francis

    2010-08-10

    Ion transport membrane system comprising (a) a pressure vessel comprising an interior, an exterior, an inlet, an inlet conduit, an outlet, and an outlet conduit; (b) a plurality of planar ion transport membrane modules disposed in the interior of the pressure vessel and arranged in series, each membrane module comprising mixed metal oxide ceramic material and having an interior region and an exterior region, wherein the inlet and the outlet of the pressure vessel are in flow communication with exterior regions of the membrane modules; (c) a gas manifold having an interior surface wherein the gas manifold is in flow communication with the interior region of each of the planar ion transport membrane modules and with the exterior of the pressure vessel; and (d) a liner disposed within any of the inlet conduit, the outlet conduit, and the interior surface of the gas manifold.

  17. Calcium phosphate nanoparticles-based systems for siRNA delivery.

    PubMed

    Xu, Xiaochun; Li, Zehao; Zhao, Xueqin; Keen, Lawrence; Kong, Xiangdong

    2016-09-01

    Despite the enormous therapeutic potential of siRNA as a treatment strategy, the delivery is still a problem due to unfavorable biodistribution profiles and poor intracellular bioavailability. Calcium phosphate (CaP) co-precipitate has been used for nearly 40 years for in vitro transfection due to its non-toxic nature and simplicity of preparation. The surface charge of CaP will be tuned into positive by surface modification, which is important for siRNA loading and crossing cell membrane without enzymatic degradation. The new siRNA carrier system will also promote the siRNA escape from lysosome to achieve siRNA sustained delivery and high-efficiency silence. In this review, we focus on the current research activity in the development of CaP nanoparticles for siRNA delivery. These nanoparticles are mainly classified into lipid coated, polymer coated and various other types for discussion. PMID:27252888

  18. Calcium phosphate nanoparticles-based systems for siRNA delivery

    PubMed Central

    Xu, Xiaochun; Li, Zehao; Zhao, Xueqin; Keen, Lawrence; Kong, Xiangdong

    2016-01-01

    Despite the enormous therapeutic potential of siRNA as a treatment strategy, the delivery is still a problem due to unfavorable biodistribution profiles and poor intracellular bioavailability. Calcium phosphate (CaP) co-precipitate has been used for nearly 40 years for in vitro transfection due to its non-toxic nature and simplicity of preparation. The surface charge of CaP will be tuned into positive by surface modification, which is important for siRNA loading and crossing cell membrane without enzymatic degradation. The new siRNA carrier system will also promote the siRNA escape from lysosome to achieve siRNA sustained delivery and high-efficiency silence. In this review, we focus on the current research activity in the development of CaP nanoparticles for siRNA delivery. These nanoparticles are mainly classified into lipid coated, polymer coated and various other types for discussion. PMID:27252888

  19. Protein extraction using the sodium bis(2-ethylhexyl) phosphate (NaDEHP) reverse micellar system.

    PubMed

    Hu, Z; Gulari, E

    1996-04-20

    The reverse micellar system of sodium bis(2-ethylhexyl) phosphate (NaDEHP)/isooctane/brine was used for liquid-liquid extraction of proteins. We investigated the solubilization of cytochrome-c and alpha-chymotrypsin into the NaDEHP reverse micellar phase by varying the pH and NaCl concentration in the aqueous phase. At neutral pH and relatively low ionic strength, the proteins are extracted into the micellar phase with high yield. By contacting the micellar phase with a divalent cation (e.g., Ca(2+)) aqueous solution, the reverse micelles are destabilized and release the protein molecules back into an aqueous solution for recovery. This method separates the proteins from the surfactant with very high overall efficiencies. PMID:18626936

  20. Thermal protection systems for hypersonic transport vehicles

    NASA Astrophysics Data System (ADS)

    Reich, G.; Hinger, J.; Huchler, M.

    1990-07-01

    Thermal protection systems (TPS) for hypersonic transport vehicles are described and evaluated. During the flight through the atmosphere moderate to high aerodynamic heating rates with corresponding high surface temperatures are generated. Therefore, a reliable light-weight but effective TPS is required, that limits the heat transfer into the central fuselage with the liquid hydrogen tank and that prevents the penetration of the temperature peak during stage separation to the load carrying structure. The heat transfer modes in the insulation are solid conduction, gas convection and radiation. Thermal protection systems based on different phenomena to reduce the heat transfer, like vacuum shingles, inert gas filled shingles, microporous insulations and multiwall structures, are described. It is demonstrated that microporous and multiwall insulations are efficient, light weight and reliable TPSs for future hypersonic transportation systems.

  1. DTS: The NOAO Data Transport System

    NASA Astrophysics Data System (ADS)

    Fitzpatrick, M.; Semple, T.

    2014-05-01

    The NOAO Data Transport System (DTS) provides high-throughput, reliable, data transfer between telescopes, pipelines and archive centers located in the Northern and Southern hemispheres. It is a distributed application using XML-RPC for command and control, and either parallel-TCP or UDT protocols for bulk data transport. The system is data-agnostic, allowing arbitrary files or directories to be moved using the same infrastructure. Data paths are configurable in the system by connecting nodes as the source or destination of data in a queue. Each leg of a data path may be configured independently based on the network environment between the sites. A queueing model is currently implemented to manage the automatic movement of data, a streaming model is planned to support arbitrarily large transfers (e.g. as in a disk recovery scenario) or to provide a 'pass-thru' interface to minize overheads. A web-based monitor allows anyone to get a graphical overview of the DTS system as it runs, operators will be able to control individual nodes in the system. Through careful tuning of the network paths DTS is able to achieve in excess of 80-percent of the nominal wire speed using only commodity networks, making it ideal for long-haul transport of large volumes of data.

  2. 360 degree vision system: opportunities in transportation

    NASA Astrophysics Data System (ADS)

    Thibault, Simon

    2007-09-01

    Panoramic technologies are experiencing new and exciting opportunities in the transportation industries. The advantages of panoramic imagers are numerous: increased areas coverage with fewer cameras, imaging of multiple target simultaneously, instantaneous full horizon detection, easier integration of various applications on the same imager and others. This paper reports our work on panomorph optics and potential usage in transportation applications. The novel panomorph lens is a new type of high resolution panoramic imager perfectly suitable for the transportation industries. The panomorph lens uses optimization techniques to improve the performance of a customized optical system for specific applications. By adding a custom angle to pixel relation at the optical design stage, the optical system provides an ideal image coverage which is designed to reduce and optimize the processing. The optics can be customized for the visible, near infra-red (NIR) or infra-red (IR) wavebands. The panomorph lens is designed to optimize the cost per pixel which is particularly important in the IR. We discuss the use of the 360 vision system which can enhance on board collision avoidance systems, intelligent cruise controls and parking assistance. 360 panoramic vision systems might enable safer highways and significant reduction in casualties.

  3. Transportable vitrification system demonstration on mixed waste. Revision 1

    SciTech Connect

    Zamecnik, J.R.; Whitehouse, J.C.; Wilson, C.N.; Van Ryn, F.R.

    1998-04-22

    The Transportable Vitrification System (TVS) is a large scale, fully integrated, vitrification system for the treatment of low-level and mixed wastes in the form of sludges, soils, incinerator ash, and many other waste streams. It was demonstrated on surrogate waste at Clemson University and at the Oak Ridge Reservation (ORR) prior to treating actual mixed waste. Treatment of a combination of dried B and C Pond sludge and CNF sludge was successfully demonstrated at ORR in 1997. The demonstration produced 7,616 kg of glass from 7,328 kg of mixed wastes with a 60% reduction in volume. Glass formulations for the wastes treated were developed using a combination of laboratory crucible studies with the actual wastes and small melter studies at Clemson with both surrogate and actual wastes. Initial characterization of the B and C Pond sludge had not shown the presence of carbon or fluoride, which required a modified glass formulation be developed to maintain proper glass redox and viscosity. The CNF sludge challenges the glass formulations due to high levels of phosphate and iron. The demonstration was delayed several times by permitting problems, a glass leak, and electrical problems. The demonstration showed that the two wastes could be successfully vitrified, although the design glass production rate was not achieved. The glass produced met the Universal Treatment Standards and the emissions from the TVS were well within the allowable permit limits.

  4. Automatic braking system modification for the Advanced Transport Operating Systems (ATOPS) Transportation Systems Research Vehicle (TSRV)

    NASA Technical Reports Server (NTRS)

    Coogan, J. J.

    1986-01-01

    Modifications were designed for the B-737-100 Research Aircraft autobrake system hardware of the Advanced Transport Operating Systems (ATOPS) Program at Langley Research Center. These modifications will allow the on-board flight control computer to control the aircraft deceleration after landing to a continuously variable level for the purpose of executing automatic high speed turn-offs from the runway. A bread board version of the proposed modifications was built and tested in simulated stopping conditions. Test results, for various aircraft weights, turnoff speed, winds, and runway conditions show that the turnoff speeds are achieved generally with errors less than 1 ft/sec.

  5. Increased phosphate transport of Arabidopsis thaliana Pht1;1 by site-directed mutagenesis of tyrosine 312 may be attributed to the disruption of homomeric interactions.

    PubMed

    Fontenot, Elena B; Ditusa, Sandra Feuer; Kato, Naohiro; Olivier, Danielle M; Dale, Renee; Lin, Wei-Yi; Chiou, Tzyy-Jen; Macnaughtan, Megan A; Smith, Aaron P

    2015-10-01

    Members of the Pht1 family of plant phosphate (Pi) transporters play vital roles in Pi acquisition from soil and in planta Pi translocation to maintain optimal growth and development. The study of the specificities and biochemical properties of Pht1 transporters will contribute to improving the current understanding of plant phosphorus homeostasis and use-efficiency. In this study, we show through split in vivo interaction methods and in vitro analysis of microsomal root tissues that Arabidopsis thaliana Pht1;1 and Pht1;4 form homomeric and heteromeric complexes. Transient and heterologous expression of the Pht1;1 variants, Pht1;1(Y312D), Pht1;1(Y312A) and Pht1;1(Y312F), was used to analyse the role of a putative Pi binding residue (Tyr 312) in Pht1;1 transporter oligomerization and function. The homomeric interaction among Pht1;1 proteins was disrupted by mutation of Tyr 312 to Asp, but not to Ala or Phe. In addition, the Pht1;1(Y312D) variant conferred enhanced Pi transport when expressed in yeast cells. In contrast, mutation of Tyr 312 to Ala or Phe did not affect Pht1;1 transport kinetics. Our study demonstrates that modifications to the Pht1;1 higher-order structure affects Pi transport, suggesting that oligomerization may serve as a regulatory mechanism for modulating Pi uptake. PMID:25754174

  6. Small Aircraft Transportation System Concept and Technologies

    NASA Technical Reports Server (NTRS)

    Holmes, Bruce J.; Durham, Michael H.; Tarry, Scott E.

    2005-01-01

    This paper summarizes both the vision and the early public-private collaborative research for the Small Aircraft Transportation System (SATS). The paper outlines an operational definition of SATS, describes how SATS conceptually differs from current air transportation capabilities, introduces four SATS operating capabilities, and explains the relation between the SATS operating capabilities and the potential for expanded air mobility. The SATS technology roadmap encompasses on-demand, widely distributed, point-to-point air mobility, through hired-pilot modes in the nearer-term, and through self-operated user modes in the farther-term. The nearer-term concept is based on aircraft and airspace technologies being developed to make the use of smaller, more widely distributed community reliever and general aviation airports and their runways more useful in more weather conditions, in commercial hired-pilot service modes. The farther-term vision is based on technical concepts that could be developed to simplify or automate many of the operational functions in the aircraft and the airspace for meeting future public transportation needs, in personally operated modes. NASA technology strategies form a roadmap between the nearer-term concept and the farther-term vision. This paper outlines a roadmap for scalable, on-demand, distributed air mobility technologies for vehicle and airspace systems. The audiences for the paper include General Aviation manufacturers, small aircraft transportation service providers, the flight training industry, airport and transportation authorities at the Federal, state and local levels, and organizations involved in planning for future National Airspace System advancements.

  7. Road Transportable Analytical Laboratory (RTAL) system

    SciTech Connect

    Finger, S.M.

    1995-10-01

    The goal of the Road Transportable Analytical Laboratory (RTAL) Project is the development and demonstration of a system to meet the unique needs of the DOE for rapid, accurate analysis of a wide variety of hazardous and radioactive contaminants in soil, groundwater, and surface waters. This laboratory system has been designed to provide the field and laboratory analytical equipment necessary to detect and quantify radionuclides, organics, heavy metals and other inorganic compounds. The laboratory system consists of a set of individual laboratory modules deployable independently or as an interconnected group to meet each DOE site`s specific needs.

  8. Human Transportation System (HTS) study, volume 2

    NASA Technical Reports Server (NTRS)

    Lance, N.; Geyer, M. S.; Gaunce, M. T.

    1993-01-01

    This report summarizes work completed under the Human Transportation System Study. This study was conducted by the New Initiatives Office at JSC with the technical support of Boeing, General Dynamics, Lockheed, McDonnell-Douglas, Martin Marietta, and Rockwell. The study was designed to generate information on determining the appropriate path to follow for new system development to meet the Nation's space transportation needs. The study evaluates 18 transportation architecture options using a parametric set of mission requirements. These options include use of current systems (e.g., Shuttle, Titan, etc. ) as well as proposed systems (e.g., PLS, Single-Stage-to-Orbit, etc.) to assess the impact of various considerations, such as the cost of alternate access, or the benefit of separating people and cargo. The architecture options are compared to each other with six measurable evaluation criteria or attributes. They are: funding profile, human safety, probability of mission success, architecture cost risk, launch schedule confidence, and environmental impact. Values for these attributes are presented for the architecture options, with pertinent conclusions and recommendations.

  9. 77 FR 24559 - Marine Transportation System National Advisory Council

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-24

    ... System National Advisory Council (MTSNAC) will hold a meeting to discuss recommendations to the Secretary on the integration of marine highways into the national transportation system and the development of... Maritime Administration Marine Transportation System National Advisory Council ACTION: National...

  10. Low energy beam transport system developments

    SciTech Connect

    Dudnikov, V.; Han, B.; Stockli, M.; Welton, R.; Dudnikova, G.

    2015-04-08

    For high brightness beam production it is important to preserve the brightness in the low energy beam transport system (LEBT) used to transport and match the ion beams to the next stage of acceleration, usually an RFQ. While electrostatic focusing can be problematic for high current beam transport, reliable electrostatic LEBT operation has been demonstrated with H{sup −} beams up to 60 mA. Now, however, it is commonly accepted that an optimal LEBT for high current accelerator applications consists of focusing solenoids with space charge compensation. Two-solenoid LEBTs are successfully used for high current (>100 mA) proton beam transport. Preservation of low emittances (~0.15 π mm-mrad) requires the addition of a heavy gas (Xe, Kr), which causes ~5% of proton loss in a 1 m long LEBT. Similar Xe densities would be required to preserve low emittances of H{sup −} beams, but such gas densities cause unacceptably high H{sup −} beam losses. A short LEBT with only one short solenoid, movable for RFQ matching, can be used for reduced negative ion stripping. A strong electrostatic-focusing LEBT has been successfully adopted for transport of high current H{sup −} beams in the SNS Front End. Some modifications of such electrostatic LEBTs are expected to improve the reliable transport of intense positive and negative ion beams without greatly degrading their low emittances. We concentrate on processes that determine the beam brightness degradation and on their prevention. Proposed improvements to the SNS electrostatic LEBT are discussed.

  11. Controlled ecological life support system: Transportation analysis

    NASA Technical Reports Server (NTRS)

    Gustan, E.; Vinopal, T.

    1982-01-01

    This report discusses a study utilizing a systems analysis approach to determine which NASA missions would benefit from controlled ecological life support system (CELSS) technology. The study focuses on manned missions selected from NASA planning forecasts covering the next half century. Comparison of various life support scenarios for the selected missions and characteristics of projected transportation systems provided data for cost evaluations. This approach identified missions that derived benefits from a CELSS, showed the magnitude of the potential cost savings, and indicated which system or combination of systems would apply. This report outlines the analytical approach used in the evaluation, describes the missions and systems considered, and sets forth the benefits derived from CELSS when applicable.

  12. Biodegradable calcium phosphate nanoparticle with lipid coating for systemic siRNA delivery.

    PubMed

    Li, Jun; Chen, Yun-Ching; Tseng, Yu-Cheng; Mozumdar, Subho; Huang, Leaf

    2010-03-19

    A lipid coated calcium phosphate (LCP) nanoparticle (NP) formulation was developed for efficient delivery of small interfering RNA (siRNA) to a xenograft tumor model by intravenous administration. Based on the previous formulation, liposome-polycation-DNA (LPD), which was a DNA-protamine complex wrapped by cationic liposome followed by post-insertion of PEG, LCP was similar to LPD NP except that the core was replaced by a biodegradable nano-sized calcium phosphate precipitate prepared by using water-in-oil micro-emulsions in which siRNA was entrapped. We hypothesized that after entering the cells, LCP would de-assemble at low pH in the endosome, which would cause endosome swelling and bursting to release the entrapped siRNA. Such a mechanism was demonstrated by the increase of intracellular Ca(2+) concentration as shown by using a calcium specific dye Fura-2. The LCP NP was further modified by post-insertion of polyethylene glycol (PEG) with or without anisamide, a sigma-1 receptor ligand for systemic administration. Luciferase siRNA was used to evaluate the gene silencing effect in H-460 cells which were stably transduced with a luciferase gene. The anisamide modified LCP NP silenced about 70% and 50% of luciferase activity for the tumor cells in culture and those grown in a xenograft model, respectively. The untargeted NP showed a very low silencing effect. The new formulation improved the in vitro silencing effect 3-4 folds compared to the previous LPD formulation, but had a negligible immunotoxicity. PMID:19919845

  13. A realtime, online automated system for measurement of Phosphate ions in atmospheric particles

    NASA Astrophysics Data System (ADS)

    Violaki, Kalliopi; Fang, Ting; Mihalopoulos, Nikos; Weber, Rodney James; Nenes, Athanasios

    2016-04-01

    Primary productivity of continental and marine ecosystems is often limited or co-limited by phosphorus. Of particular interest is the role of phosphorus in marine primary productivity, owing to its potential for affecting the concentration of atmospheric carbon dioxide. The atmosphere is considered a principal source of externally-supplied nutrients for large areas of the surface ocean, and oligotrophic open oceans in particular. Atmospheric inorganic P species (e.g. mono- or diprotonated orthophosphate) comprise the most bioavailable P form, and have been studied for many decades. Nevertheless, there are very large uncertainties in the phosphate biogeochemical budget due to the lack of observations and the poor match of the model to observations. This study presents a novel automated on-line, real-time analytical method for the analysis of water-soluble PO4-3 ions in atmospheric particles. The instrumentation consists of a particle-into-liquid sampler (PILS) coupled with a reaction coil to allow reagents to interact with the PILS liquid flow; the composite flow is then introduced into a mini spectrophotometer, which is equipped with a long path length of 250cm Liquid Wavequide Capillary Cell (LWCC), achieving low detection limit. This new system overcomes the limitations on detection and time resolution, as the configuration presented allows for measurement with 8 minute resolution. The data, when combined with routine PILS-IC or aerosol mass spectrometry, allows for an unprecedented insight towards the drivers of phosphate solubility and its relation to acidification from atmospheric acids. We present results for concentration of PM2.5 PO4-3 in Atlanta Georgia for a 2 month period (February-March, 2015) and the Eastern Mediterranean and its relation to aerosol acidity and other meteorological parameters. The results are discussed together with future directions towards optimized performance during long periods of operation.

  14. Heat transport system, method and material

    DOEpatents

    Musinski, D.L.

    1987-04-28

    A heat transport system, method and composite material are disclosed in which a plurality of hollow spherical shells or microspheres having an outside diameter of less than or equal to 500 microns are encapsulated or embedded within a bulk material. Each shell has captured therein a volatile working fluid, such that each shell operates as a microsized heat pipe for conducting heat through the composite structure. 1 fig.

  15. A novel motor, KIF13A, transports mannose-6-phosphate receptor to plasma membrane through direct interaction with AP-1 complex.

    PubMed

    Nakagawa, T; Setou, M; Seog, D; Ogasawara, K; Dohmae, N; Takio, K; Hirokawa, N

    2000-11-10

    Intracellular transport mediated by kinesin superfamily proteins (KIFs) is a highly regulated process. The molecular mechanism of KIFs binding to their respective cargoes remains unclear. We report that KIF13A is a novel plus end-directed microtubule-dependent motor protein and associates with beta 1-adaptin, a subunit of the AP-1 adaptor complex. The cargo vesicles of KIF13A contained AP-1 and mannnose-6-phosphate receptor (M6PR). Overexpression of KIF13A resulted in mislocalization of the AP-1 and the M6PR. Functional blockade of KIF13A reduced cell surface expression of the M6PR. Thus, KIF13A transports M6PR-containing vesicles and targets the M6PR from TGN to the plasma membrane via direct interaction with the AP-1 adaptor complex. PMID:11106728

  16. Cargo transportation by airships: A systems study

    NASA Technical Reports Server (NTRS)

    Huang, C. J.; Dalton, C.

    1976-01-01

    A systems engineering study of a lighter than air airship transportation system was conducted. The feasibility of the use of airships in hauling cargo was demonstrated. Social, legal, environmental and political factors were considered as well as the technical factors necessary to design an effective airship transportation system. In order to accomplish an effective airship transportation program two phases of implementation were recommended. Phase I would involve a fleet of rigid airships of 3.5 million cubic feet displacement capable of carrying 25 tons of cargo internal to the helium-filled gas bag. The Phase I fleet would demonstrate the economic and technical feasibility of modern-day airships while providing a training capability for the construction and operation of larger airships. The Phase II portion would be a fleet of rigid airships of 12 million cubic feet displacement capable of carrying a cargo of 100 tons a distance of 2,000 miles at a cruising speed of 60 mph. An economic analysis is given for a variety of missions for both Phase I and Phase II airships.

  17. The Palm Desert renewable [hydrogen] transportation system

    SciTech Connect

    Chamberlin, C.E.; Lehman, P.

    1998-08-01

    This paper describes the Schatz Energy Research Center (SERC) progress on the Palm Desert Renewable Hydrogen Transportation System Project for the period June 1997 through May 1998. The project began in March 1996. The goal of the Palm Desert Project is to develop a clean and sustainable transportation system for a community. The project demonstrates the practical utility of hydrogen as a transportation fuel and the proton exchange membrane (PEM) fuel cell as a vehicle power system. The project includes designing and building 4 fuel cell powered vehicles, a solar hydrogen generating and refueling station, and a fuel cell vehicle diagnostic center. Over this last year, SERC has built a fuel cell powered neighborhood electric vehicle and delivered it to the City of Palm Desert. The design of the hydrogen refueling station is near completion and it is anticipated that construction will be complete in the fall of 1998. The vehicles are currently being refueled at a temporary refueling station. The diagnostic center is being designed and maintenance procedures as well as computer diagnostic programs for the fuel cell vehicles are being developed. City employees are driving the vehicles daily and monitoring data are being collected. The drivers are pleased with the performance of the vehicles.

  18. Phosphate salts

    MedlinePlus

    ... as a laxative to clean the bowels before surgery or intestinal tests. Healthcare providers sometimes give potassium phosphate intravenously (by IV) for treating low phosphate and high calcium levels in the blood, and for preventing low phosphate in patients who are being tube-fed.

  19. Next generation: In-space transportation system(s)

    NASA Technical Reports Server (NTRS)

    Huffaker, Fredrick; Redus, Jerry; Kelley, David L.

    1991-01-01

    The development of the next generation In-Space Transportation System presents a unique challenge to the design of a propulsion system for the Space Exploration Initiative (SEI). Never before have the requirements for long-life, multiple mission use, space basing, high reliability, man-rating, and minimum maintenance come together with performance in one system that must protect the lives of space travelers, support the mission logistics needs, and do so at an acceptable cost. The challenge that is presented is to quantify the bounds of these requirements. The issue is one of degree. The length of acceptable life in space, the time it takes for reuse to pay off, and the degree to which space basing is practical (full, partial, or expended) are the issues that determine the reusable bounds of a design and include dependability, contingency capabilities, resilency, and minimum dependence on a maintenance node in preparation for and during a mission. Missions to planet earth, other non-NASA missions, and planetary missions will provide important but less demanding requirements for the transportation systems of the future. The mission proposed for the SEI require a family of transportation vehicles to meet the requirements for establishing a permanent human presence on the Moon and eventually on Mars. Specialized vehicles are needed to accomplish the different phases of each mission. These large scale missions require assembly in space and will provide the greatest usage of the planned integrated transportation system. The current approach to defining the In-Space Transportation System for the SEI Moon missions with later Mars mission applications is presented. Several system development options, propulsion concepts, current/proposed activities are reviewed, and key propulsion design criteria, issues, and technology challenges for the next generation In-Space Transportation System(s) are outlined.

  20. Preliminary observations on high energy phosphates and metabolic pathway and transporter potentials in extensor carpi radialis brevis and trapezius muscles of women with work-related myalgia.

    PubMed

    Green, Howard J; Ranney, Don; Burnett, Margaret; Galvin, Patti; Kyle, Natasha; Lounsbury, David; Ouyang, Jing; Smith, Ian C; Stewart, Riley; Tick, Heather; Tupling, A Russell

    2014-11-01

    This study compared both the extensor carpi radialis brevis (ECRB) and the trapezius (TRAP) muscles of women with work-related myalgia (WRM) with healthy controls (CON) to determine whether abnormalities existed in cellular energy status and the potentials of the various metabolic pathways and segments involved in energy production and substrate transport. For both the ECRB (CON, n = 6-9; WRM, n = 13) and the TRAP (CON, n = 6-7; WRM, n = 10), no differences (P > 0.05) were found for the concentrations (in millimoles per kilogram of dry mass) of ATP, PCr, lactate, and glycogen. Similarly, with one exception, the maximal activities (in moles per milligram of protein per hour) of mitochondrial enzymes representative of the citric acid cycle (CAC), the electron transport chain (ETC), and β-oxidation, as well as the cytosolic enzymes involved in high energy phosphate transfer, glycogenolysis, glycolysis, lactate oxidation, and glucose phosphorylation were not different (P > 0.05). The glucose transporters GLUT1 and GLUT4, and the monocarboxylate transporters MCT1 and MCT4, were also normal in WRM. It is concluded that, in general, abnormalities in the resting energy and substrate state, the potential of the different metabolic pathways and segments, as well as the glucose and monocarboxylate transporters do not appear to be involved in the cellular pathophysiology of WRM. PMID:25358071

  1. High Energy Particle Transport Code System.

    Energy Science and Technology Software Center (ESTSC)

    2003-12-17

    Version 00 NMTC/JAM is an upgraded version of the code CCC-694/NMTC-JAERI97, which was developed in 1982 at JAERI and is based on the CCC-161/NMTC code system. NMTC/JAM simulates high energy nuclear reactions and nuclear meson transport processes. The applicable energy range of NMTC/JAM was extended in principle up to 200 GeV for nucleons and mesons by introducing the high energy nuclear reaction code Jet-Aa Microscopic (JAM) for the intra-nuclear cascade part. For the evaporation andmore » fission process, a new model, GEM, can be used to describe the light nucleus production from the excited residual nucleus. According to the extension of the applicable energy, the nucleon-nucleus non-elastic, elastic and differential elastic cross section data were upgraded. In addition, the particle transport in a magnetic field was implemented for beam transport calculations. Some new tally functions were added, and the format of input and output of data is more user friendly. These new calculation functions and utilities provide a tool to carry out reliable neutronics study of a large scale target system with complex geometry more accurately and easily than with the previous model. It implements an intranuclear cascade model taking account of the in-medium nuclear effects and the preequilibrium calculation model based on the exciton one. For treating the nucleon transport process, the nucleon-nucleus cross sections are revised to those derived by the systematics of Pearlstein. Moreover, the level density parameter derived by Ignatyuk is included as a new option for particle evaporation calculation. A geometry package based on the Combinatorial Geometry with multi-array system and the importance sampling technique is implemented in the code. Tally function is also employed for obtaining such physical quantities as neutron energy spectra, heat deposition and nuclide yield without editing a history file. The code can simulate both the primary spallation reaction and the

  2. Miniature Heat Transport System for Nanosatellite Technology

    NASA Technical Reports Server (NTRS)

    Douglas, Donya M,

    1999-01-01

    The scientific understanding of key physical processes between the Sun and the Earth require simultaneous measurements from many vantage points in space. Nano-satellite technologies will enable a class of constellation missions for the NASA Space Science Sun-Earth Connections. This recent emphasis on the implementation of smaller satellites leads to a requirement for development of smaller subsystems in several areas. Key technologies under development include: advanced miniaturized chemical propulsion; miniaturized sensors; highly integrated, compact electronics; autonomous onboard and ground operations; miniatures low power tracking techniques for orbit determination; onboard RF communications capable of transmitting data to the ground from far distances; lightweight efficient solar array panels; lightweight, high output battery cells; lightweight yet strong composite materials for the nano-spacecraft and deployer-ship structures. These newer smaller systems may have higher power densities and higher thermal transport requirements than seen on previous small satellites. Furthermore, the small satellites may also have a requirement to maintain thermal control through extended earth shadows, possibly up to 8 hours long. Older thermal control technology, such as heaters, thermostats, and heat pipes, may not be sufficient to meet the requirements of these new systems. Conversely, a miniature two-phase heat transport system (Mini-HTS) such as a Capillary Pumped Loop (CPL) or Loop Heat Pipe (LBP) is a viable alternative. A Mini-HTS can provide fine temperature control, thermal diode action, and a highly efficient means of heat transfer. The Mini-HTS would have power capabilities in the range of tens of watts or less and provide thermal control over typical spacecraft ranges. The Mini-HTS would allow the internal portion of the spacecraft to be thermally isolated from the external radiator, thus protecting the internal components from extreme cold temperatures during an

  3. Heavy particle transport in sputtering systems

    NASA Astrophysics Data System (ADS)

    Trieschmann, Jan

    2015-09-01

    This contribution aims to discuss the theoretical background of heavy particle transport in plasma sputtering systems such as direct current magnetron sputtering (dcMS), high power impulse magnetron sputtering (HiPIMS), or multi frequency capacitively coupled plasmas (MFCCP). Due to inherently low process pressures below one Pa only kinetic simulation models are suitable. In this work a model appropriate for the description of the transport of film forming particles sputtered of a target material has been devised within the frame of the OpenFOAM software (specifically dsmcFoam). The three dimensional model comprises of ejection of sputtered particles into the reactor chamber, their collisional transport through the volume, as well as deposition of the latter onto the surrounding surfaces (i.e. substrates, walls). An angular dependent Thompson energy distribution fitted to results from Monte-Carlo simulations is assumed initially. Binary collisions are treated via the M1 collision model, a modified variable hard sphere (VHS) model. The dynamics of sputtered and background gas species can be resolved self-consistently following the direct simulation Monte-Carlo (DSMC) approach or, whenever possible, simplified based on the test particle method (TPM) with the assumption of a constant, non-stationary background at a given temperature. At the example of an MFCCP research reactor the transport of sputtered aluminum is specifically discussed. For the peculiar configuration and under typical process conditions with argon as process gas the transport of aluminum sputtered of a circular target is shown to be governed by a one dimensional interaction of the imposed and backscattered particle fluxes. The results are analyzed and discussed on the basis of the obtained velocity distribution functions (VDF). This work is supported by the German Research Foundation (DFG) in the frame of the Collaborative Research Centre TRR 87.

  4. Corridor guided transport system utilizing permanent magnet levitation

    SciTech Connect

    Geraghty, J.J.; Poland, A.P.; Lombardi, J.A.

    1995-07-01

    The invention relates to a corridor guided transport system including a guided goods conveyance container utilizing permanent magnet levitation. The transport system of the invention eliminates the need for the wheel and track arrangement presently required by known and utilized conventional train systems and also required by some conventional magnetic levitation transport systems and, as a result, is safer to operate and maintain than either of these known transportation systems.

  5. Hyperspectral range imaging for transportation systems evaluation

    NASA Astrophysics Data System (ADS)

    Bridgelall, Raj; Rafert, J. B.; Atwood, Don; Tolliver, Denver D.

    2016-04-01

    Transportation agencies expend significant resources to inspect critical infrastructure such as roadways, railways, and pipelines. Regular inspections identify important defects and generate data to forecast maintenance needs. However, cost and practical limitations prevent the scaling of current inspection methods beyond relatively small portions of the network. Consequently, existing approaches fail to discover many high-risk defect formations. Remote sensing techniques offer the potential for more rapid and extensive non-destructive evaluations of the multimodal transportation infrastructure. However, optical occlusions and limitations in the spatial resolution of typical airborne and space-borne platforms limit their applicability. This research proposes hyperspectral image classification to isolate transportation infrastructure targets for high-resolution photogrammetric analysis. A plenoptic swarm of unmanned aircraft systems will capture images with centimeter-scale spatial resolution, large swaths, and polarization diversity. The light field solution will incorporate structure-from-motion techniques to reconstruct three-dimensional details of the isolated targets from sequences of two-dimensional images. A comparative analysis of existing low-power wireless communications standards suggests an application dependent tradeoff in selecting the best-suited link to coordinate swarming operations. This study further produced a taxonomy of specific roadway and railway defects, distress symptoms, and other anomalies that the proposed plenoptic swarm sensing system would identify and characterize to estimate risk levels.

  6. An overview of European space transportation systems

    NASA Technical Reports Server (NTRS)

    Lo, R. E.

    1985-01-01

    With the completion of the launch rocket series Ariane 1 to 4, Europe will have reached the same capacity to transport commercial payloads as the USA has with the Space Shuttle and the kick stages which are presently operative. The near term development of these capacities would require Europe to develop a larger launch rocket, Araine 5. Further motivations for this rocket are access to manned spaceflight, the development of an European space station, and the demand for shuttle technology. Shuttle technology is the subject of research being done in France on the winged re-entry vehicle Hermes. Operation of the European space station Columbus will require development of an interorbital transport system to facilitate traffic between the various segments of the space station. All European space transportation systems will have to match their quality to that of the other countries involve in space flight. All areas of development are marked not only by possible cooperation but also by increased competition because of increasing commercialization of space flight.

  7. National Space Transportation System (NSTS) technology needs

    NASA Technical Reports Server (NTRS)

    Winterhalter, David L.; Ulrich, Kimberly K.

    1990-01-01

    The National Space Transportation System (NSTS) is one of the Nation's most valuable resources, providing manned transportation to and from space in support of payloads and scientific research. The NSTS program is currently faced with the problem of hardware obsolescence, which could result in unacceptable schedule and cost impacts to the flight program. Obsolescence problems occur because certain components are no longer being manufactured or repair turnaround time is excessive. In order to achieve a long-term, reliable transportation system that can support manned access to space through 2010 and beyond, NASA must develop a strategic plan for a phased implementation of enhancements which will satisfy this long-term goal. The NSTS program has initiated the Assured Shuttle Availability (ASA) project with the following objectives: eliminate hardware obsolescence in critical areas, increase reliability and safety of the vehicle, decrease operational costs and turnaround time, and improve operational capability. The strategy for ASA will be to first meet the mandatory needs - keep the Shuttle flying. Non-mandatory changes that will improve operational capability and enhance performance will then be considered if funding is adequate. Upgrade packages should be developed to install within designated inspection periods, grouped in a systematic approach to reduce cost and schedule impacts, and allow the capability to provide a Block 2 Shuttle (Phase 3).

  8. Technological Support for Logistics Transportation Systems

    NASA Astrophysics Data System (ADS)

    Bujak, Andrzej; Śliwa, Zdzisław; Gębczyńska, Alicja

    The modern world is changing introducing robots, remotely controlled vehicles and other crewless means of transportation to reduce people's mistakes, as the main cause of incidents and crashes during traffic. New technologies are supporting operators and drivers, and according to some studies they can even replace them. Such programs as: AHS, UAH, IVBSS or MTVR are under development to improve traffic flow and its safety, to reduce traffic hazards and crashes. It is necessary to analyze such concepts and implement them boldly, including Polish logistics' companies, new programs, highways' system etc., as they will be applied in the future, so it is necessary to prepare logistics infrastructure ahead of time in order to capitalize on these improvements. The problem is quite urgent as transportation in the country must not be outdated to meet clients' expectations and to keep pace with competing foreign companies.

  9. Design of Large Momentum Acceptance Transport Systems

    SciTech Connect

    D.R. Douglas

    2005-05-01

    The use of energy recovery to enable high power linac operation often gives rise to an attendant challenge--the transport of high power beams subtending large phase space volumes. In particular applications--such as FEL driver accelerators--this manifests itself as a requirement for beam transport systems with large momentum acceptance. We will discuss the design, implementation, and operation of such systems. Though at times counterintuitive in behavior (perturbative descriptions may, for example, be misleading), large acceptance systems have been successfully utilized for generations as spectrometers and accelerator recirculators [1]. Such systems are in fact often readily designed using appropriate geometric descriptions of beam behavior; insight provided using such a perspective may in addition reveal inherent symmetries that simplify construction and improve operability. Our discussion will focus on two examples: the Bates-clone recirculator used in the Jefferson Lab 10 kW IR U pgrade FEL (which has an observed acceptance of 10% or more) and a compaction-managed mirror-bend achromat concept with an acceptance ranging from 50 to 150 MeV.

  10. Chemically generated convective transport in microfluidic system

    NASA Astrophysics Data System (ADS)

    Shklyaev, Oleg; Das, Sambeeta; Altemose, Alicia; Shum, Henry; Balazs, Anna; Sen, Ayusman

    High precision manipulation of small volumes of fluid, containing suspended micron sized objects like cells, viruses, and large molecules, is one of the main goals in designing modern lab-on-a-chip devices which can find a variety of chemical and biological applications. To transport the cargo toward sensing elements, typical microfluidic devices often use pressure driven flows. Here, we propose to use enzymatic chemical reactions which decompose reagent into less dense products and generate flows that can transport particles. Density variations that lead to flow in the assigned direction are created between the place where reagent is fed into the solution and the location where it is decomposed by enzymes attached to the surface of the microchannel. When the reagent is depleted, the fluid motion stops and particles sediment to the bottom. We demonstrate how the choice of chemicals, leading to specific reaction rates, can affect the transport properties. In particular, we show that the intensity of the fluid flow, the final location of cargo, and the time for cargo delivery are controlled by the amount and type of reagent in the system.

  11. Anomalous transport in ergodic lattice systems

    NASA Astrophysics Data System (ADS)

    Bar Lev, Yevgeny; Reichman, David R.

    Many-body localization transition is a peculiar dynamical transition between ergodic and non-ergodic phases, which may occur at any temperature and in any dimension. For temperatures below the transition the system is nonergodic and localized, such that conductivity strictly vanishes at the thermodynamic limit, while for temperatures above the transition the system is thermal and conductive. In this talk I will present a comprehensive study of the dynamical properties of the ergodic phase in one and two dimensional generic disordered and interacting systems, conducted using a combination of nonequilibrium diagrammatic techniques and numerically exact methods. I will show that the ergodic phase, which was expected to be diffusive, exhibits anomalous transport regime for nontrivial times and explain how our findings settle with phenomenological theoretical models. NSF-CHE-1644802.

  12. Saenger space transportation system - Progress report

    NASA Astrophysics Data System (ADS)

    Koelle, Dietrich E.; Kuczera, Heribert

    1992-10-01

    The first part of the Saenger System Definition Study within the German National Hypersonics Technology Program (1988 to 1992) was completed by mid-1990. This paper summarizes the progress made and the status of the project as of that milestone which was formally completed by the System Study Presentation in July 1990. For the second phase of the study (mid-1990 to end 1992) the original philosophy of different upper stages for manned space operations and for unmanned cargo/payloads transportation is being maintained, however, a winged unmanned Horus-C version has been found to be a better solution than the originally conceived expendable ballistic stage Cargus. The advantage of this twin-Horus Concept is the greater commonality of both upper stages as well as the new return capability of payloads up to 7 Mg. The maximum payload capability of the expendable stage was of course higher, but it is assumed that for larger payloads a complementary launch vehicle (i.e. Ariane 5) will be further available. The paper also presents new data about the Horus return flight trajectories as well as on the aerothermodynamic studies and experimental work. Finally, aspects of mission operations and economics are discussed which are of special importance for such an advanced reusable space transportation system.

  13. Space transportation system biomedical operations support study

    NASA Technical Reports Server (NTRS)

    White, S. C.

    1983-01-01

    The shift of the Space Transportation System (STS) flight tests of the orbiter vehicle to the preparation and flight of the payloads is discussed. Part of this change is the transition of the medical and life sciences aspects of the STS flight operations to reflect the new state. The medical operations, the life sciences flight experiments support requirements and the intramural research program expected to be at KSC during the operational flight period of the STS and a future space station are analyzed. The adequacy of available facilities, plans, and resources against these future needs are compared; revisions and/or alternatives where appropriate are proposed.

  14. National Space Transportation Systems Program mission report

    NASA Technical Reports Server (NTRS)

    Collins, M. A., Jr.; Aldrich, A. D.; Lunney, G. S.

    1984-01-01

    The STS 41-C National Space Transportation Systems Program Mission Report contains a summary of the major activities and accomplishments of the eleventh Shuttle flight and fifth flight of the OV-099 vehicle, Challenger. Also summarized are the significant problems that occurred during STS 41-C, and a problem tracking list that is a complete list of all problems that occurred during the flight. The major objectives of flight STS 41-C were to successfully deploy the LDEF (long duration exposure facility) and retrieve, repair and redeploy the SMM (Solar Maximum Mission) spacecraft, and perform functions of IMAX and Cinema 360 cameras.

  15. Operating systems in the air transportation environment.

    NASA Technical Reports Server (NTRS)

    Cherry, G. W.

    1971-01-01

    Consideration of the problems facing air transport at present, and to be expected in the future. In the Northeast Corridor these problems involve community acceptance, airway and airport congestion and delays, passenger acceptance, noise reduction, and improvements in low-density short-haul economics. In the development of a superior short-haul operating system, terminal-configured vs cruise-configured vehicles are evaluated. CTOL, STOL, and VTOL aircraft of various types are discussed. In the field of noise abatement, it is shown that flight procedural techniques are capable of supplementing ?quiet engine' technology.

  16. Conceptual design of a Mars transportation system

    NASA Technical Reports Server (NTRS)

    1992-01-01

    In conjunction with NASA Marshall Space Flight Center and several major aerospace corporations the University of Minnesota has developed a scenario to place humans on Mars by the year 2016. The project took the form of a year-long design course in the senior design curricula at the University's Aerospace Engineering and Mechanics Department. Students worked with the instructor, teaching assistants and engineers in industry to develop a vehicle and the associated mission profile to fulfill the requirements of the Mars Transportation System. This report is a summary of the final design and the process though which the final product was developed.

  17. Future Intelligent Transportation Systems and Sensors

    NASA Astrophysics Data System (ADS)

    Hosaka, Akio

    A road vehicle traffic contributes to the social improvement greatly, but it has big problems such as safety, congestion, environment, energy, elder people driving and adaptation to information society. ITS (Intelligent Transportation Systems) is expected as a direction solving these. The intellectual function about a road vehicle traffic depended on most of human beings. ITS helps intellectual functions such as information sensing, situation recognition, judgment, planning and operation. A sensor detecting information is an important key in ITS. I describe expectation to a sensor in ITS.

  18. Progress toward an integrated advanced transportation system

    NASA Technical Reports Server (NTRS)

    Branscome, Darrell R.

    1989-01-01

    Long term mission and payload mass requirements have been inventoried in NASA's Civil Needs Data Base, thereby establishing a framework for the analysis of launch vehicle requirements as well as time-frame requirements for the availability of specific launch vehicle and orbit-transfer vehicle capabilities. The Next Manned Transportation System studies conducted within this framework focus on the definition of options for manned flight operations beyond current Space Shuttle capabilities. Also under way are Assured Crew Return Capability studies for the Space Station Freedom, and Space Transfer Vehicle studies for a space-based aerobraking spacecraft.

  19. Mars integrated transportation system multistage Mars mission

    NASA Technical Reports Server (NTRS)

    1991-01-01

    In accordance with the objective of the Mars Integrated Transport System (MITS) program, the Multistage Mars Mission (MSMM) design team developed a profile for a manned mission to Mars. The purpose of the multistage mission is to send a crew of five astronauts to the martian surface by the year 2019. The mission continues man's eternal quest for exploration of new frontiers. This mission has a scheduled duration of 426 days that includes experimentation en route as well as surface exploration and experimentation. The MSMM is also designed as a foundation for a continuing program leading to the colonization of the planet Mars.

  20. A space transportation system operations model

    NASA Technical Reports Server (NTRS)

    Morris, W. Douglas; White, Nancy H.

    1987-01-01

    Presented is a description of a computer program which permits assessment of the operational support requirements of space transportation systems functioning in both a ground- and space-based environment. The scenario depicted provides for the delivery of payloads from Earth to a space station and beyond using upper stages based at the station. Model results are scenario dependent and rely on the input definitions of delivery requirements, task times, and available resources. Output is in terms of flight rate capabilities, resource requirements, and facility utilization. A general program description, program listing, input requirements, and sample output are included.

  1. 49 CFR 37.33 - Airport transportation systems.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... systems operated by public airport operators, which provide designated public transportation and connect.... Public airports which operate fixed route transportation systems are subject to the requirements of this... part. (b) Fixed-route transportation systems operated by public airport operators between the...

  2. Denitrification-coupled iron(ii) oxidation: a key process regulating the fate and transport of nitrate, phosphate, and arsenic in a wastewater-contaminated aquifer

    USGS Publications Warehouse

    Smith, Richard L.; Kent, Douglas B.; Repert, Deborah A.; Hart, C. P.

    2008-01-01

    Denitrification in the subsurface is often viewed as a heterotrophic process. However, some denitrifiers can also utilize inorganic electron donors. In particular, Fe(II), which is common in many aquifers, could be an important reductant for contaminant nitrate. Anoxic iron oxidation would have additional consequences, including decreased mobility for species like arsenic and phosphate, which bind strongly to hydrous Fe(III) oxide. A study was conducted in a wastewater contaminant plume on Cape Cod to assess the potential for denitrification- coupled Fe(II) oxidation. Previous changes in wastewater disposal upgradient of the study area had resulted in nitrate being transported into a portion of the anoxic zone of the plume and decreased concentrations of Fe(II), phosphate, and arsenic. A series of anoxic tracers (groundwater + nitrate + bromide) were injected into the unaffected, Fe(II)-containing zone under natural gradient conditions. Denitrification was stimulated within 1 m of transport (4 days) for both low and high (100 & 1000 μM) nitrate additions, initially producing stiochiometric quantities of nitrous oxide (>300 μM N) and trace amounts of nitrite. Subsequent injections at the same site reduced nitrate even more rapidly and produced less nitrous oxide, especially over longer transport distances. Fe(II) and nitrate concentrations decreased together and this was accompanied by an increase in colloidal Fe(III) and decreases in pH, total arsenic, and phosphate concentrations. All plume constituents returned to background levels several weeks after the tracer tests were completed. Groundwater microorganisms collected on filters during the tracer test rapidly and immediately reduced nitrite and oxidized Fe(II) in 3-hr laboratory incubations. Several pure cultures of Fe(II)-oxidizing denitrifying bacteria were isolated from core material and subsequently characterized. All of the isolates were mixotrophic, simultaneously oxidizing organic carbon and Fe

  3. Denitrification-Coupled Iron(II) Oxidation: A Key Process Regulating the Fate and Transport of Nitrate, Phosphate, and Arsenic in a Wastewater-Contaminated Aquifer

    NASA Astrophysics Data System (ADS)

    Smith, R. L.; Kent, D. B.; Repert, D. A.; Hart, C. P.

    2007-12-01

    Denitrification in the subsurface is often viewed as a heterotrophic process. However, some denitrifiers can also utilize inorganic electron donors. In particular, Fe(II), which is common in many aquifers, could be an important reductant for contaminant nitrate. Anoxic iron oxidation would have additional consequences, including decreased mobility for species like arsenic and phosphate, which bind strongly to hydrous Fe(III) oxide. A study was conducted in a wastewater contaminant plume on Cape Cod to assess the potential for denitrification- coupled Fe(II) oxidation. Previous changes in wastewater disposal upgradient of the study area had resulted in nitrate being transported into a portion of the anoxic zone of the plume and decreased concentrations of Fe(II), phosphate, and arsenic. A series of anoxic tracers (groundwater + nitrate + bromide) were injected into the unaffected, Fe(II)-containing zone under natural gradient conditions. Denitrification was stimulated within 1 m of transport (4 days) for both low and high (100 & 1000 μM) nitrate additions, initially producing stiochiometric quantities of nitrous oxide (>300 μM N) and trace amounts of nitrite. Subsequent injections at the same site reduced nitrate even more rapidly and produced less nitrous oxide, especially over longer transport distances. Fe(II) and nitrate concentrations decreased together and this was accompanied by an increase in colloidal Fe(III) and decreases in pH, total arsenic, and phosphate concentrations. All plume constituents returned to background levels several weeks after the tracer tests were completed. Groundwater microorganisms collected on filters during the tracer test rapidly and immediately reduced nitrite and oxidized Fe(II) in 3-hr laboratory incubations. Several pure cultures of Fe(II)-oxidizing denitrifying bacteria were isolated from core material and subsequently characterized. All of the isolates were mixotrophic, simultaneously oxidizing organic carbon and Fe

  4. Evaluation for rock phosphate solubilization in fermentation and soil-plant system using a stress-tolerant phosphate-solubilizing Aspergillus niger WHAK1.

    PubMed

    Xiao, Chunqiao; Zhang, Huaxiang; Fang, Yujuan; Chi, Ruan

    2013-01-01

    A strain WHAK1, identified as Aspergillus niger, was isolated from Yichang phosphate mines in Hubei province of China. The fungus developed a phosphate solubilization zone on modified National Botanical Research Institute's phosphate growth (NBRIP) agar medium, supplemented with tricalcium phosphate. The fungus was applied in a repeated-batch fermentation process in order to test its effect on solubilization of rock phosphate (RP). The results showed that A. niger WHAK1 could effectively solubilize RP in NBRIP liquid medium and released soluble phosphate in the broth, which can be illustrated by the observation of scanning electron microscope, energy-dispersive X-ray microanalysis, and Fourier transform infrared spectroscopy. Acidification of the broth seemed to be the major mechanism for RP solubilization by the fungus. Indeed, multiple organic acids (mainly gluconic acid) were detected in the broth by high-performance liquid chromatography analysis. These organic acids caused a significant drop of pH and an obvious rise of titratable acidity in the broth. The fungus also exhibited high levels of tolerance against temperature, pH, salinity, and desiccation stresses, although a significant decline in the fungal growth and release of soluble phosphate was marked under increasing intensity of stress parameters. Further, the fungus was introduced into the soil supplemented with RP to analyze its effect on plant growth and phosphate uptake of wheat plants. The result revealed that inoculation of A. niger WHAK1 significantly increased the growth and phosphate uptake of wheat plants in the RP-amended soil compared to the control soil. PMID:23229476

  5. The Sink-Specific Plastidic Phosphate Transporter PHT4;2 Influences Starch Accumulation and Leaf Size in Arabidopsis1[W][OA

    PubMed Central

    Irigoyen, Sonia; Karlsson, Patrik M.; Kuruvilla, Jacob; Spetea, Cornelia; Versaw, Wayne K.

    2011-01-01

    Nonphotosynthetic plastids are important sites for the biosynthesis of starch, fatty acids, and amino acids. The uptake and subsequent use of cytosolic ATP to fuel these and other anabolic processes would lead to the accumulation of inorganic phosphate (Pi) if not balanced by a Pi export activity. However, the identity of the transporter(s) responsible for Pi export is unclear. The plastid-localized Pi transporter PHT4;2 of Arabidopsis (Arabidopsis thaliana) is expressed in multiple sink organs but is nearly restricted to roots during vegetative growth. We identified and used pht4;2 null mutants to confirm that PHT4;2 contributes to Pi transport in isolated root plastids. Starch accumulation was limited in pht4;2 roots, which is consistent with the inhibition of starch synthesis by excess Pi as a result of a defect in Pi export. Reduced starch accumulation in leaves and altered expression patterns for starch synthesis genes and other plastid transporter genes suggest metabolic adaptation to the defect in roots. Moreover, pht4;2 rosettes, but not roots, were significantly larger than those of the wild type, with 40% greater leaf area and twice the biomass when plants were grown with a short (8-h) photoperiod. Increased cell proliferation accounted for the larger leaf size and biomass, as no changes were detected in mature cell size, specific leaf area, or relative photosynthetic electron transport activity. These data suggest novel signaling between roots and leaves that contributes to the regulation of leaf size. PMID:21960139

  6. Beneficial phosphate recovery from reverse osmosis (RO) concentrate of an integrated membrane system using polymeric ligand exchanger (PLE).

    PubMed

    Kumar, Manish; Badruzzaman, Mohammad; Adham, Samer; Oppenheimer, Joan

    2007-05-01

    Phosphorus (P) discharge to surface water is a major environmental problem. Wastewater treatment is targeted towards removal of this nutrient to prevent degradation of surface water. Integrated membrane systems (IMS) are increasingly being considered for wastewater reclamation, and provide excellent removal of P compounds. However, reverse osmosis (RO), which forms an integral part of these IMSs, concentrates most dissolved substances including P-species such as phosphates in the RO waste stream. In this study, removal of phosphate from this stream using polymeric ligand exchange (PLE) resins was investigated. Further, the possibility of phosphate recovery through struvite (MgNH(4)PO(4).6H(2)O) precipitation was tested. Struvite has been promoted as a slow release fertilizer in recent years. This study demonstrates that PLEs can be successfully used to remove phosphate from RO-concentrate, and to recover more than 85% of the adsorbed phosphorus from the exhausted media and precipitated as a beneficial product (struvite). The approach, presented in this study, suggests advantages of providing economic benefit from a waste product (RO) while avoiding phosphorus discharge to the environment. PMID:17379269

  7. Effects of tris(2-butoxyethyl) phosphate exposure on endocrine systems and reproduction of zebrafish (Danio rerio).

    PubMed

    Kwon, Bareum; Shin, Hyejin; Moon, Hyo-Bang; Ji, Kyunghee; Kim, Ki-Tae

    2016-07-01

    Tris(2-butoxyethyl) phosphate (TBEOP), a widely used organophosphate flame retardant, has frequently been detected both in the environment and the biota. However, limited information is available on the effects of TBEOP on the endocrine system and its underlying mechanisms. We exposed adult zebrafish pairs to TBEOP at concentrations of 0, 2.1, 11, and 118 μg/L for 21 d, and investigated the effects on gene transcription and hormone production related to the hypothalamic-pituitary-gonadal (HPG) axis, and on reproduction. The adverse effects on the F1 generation were further examined. In male fish, plasma concentrations of 17β-estradiol were significantly increased along with up-regulation of cyp19a. Exposure to TBEOP at 118 μg/L led to a significant decrease in average egg production. Exposure of the F0 generation to TBEOP delayed hatching and lowered hatching rates in the F1 generation. The results demonstrate that exposure to TBEOP at environmentally relevant concentration levels could affect the sex hormone balance by altering regulatory circuits of the HPG axis, eventually leading to disruption of reproductive performance and the development of offspring. PMID:27131816

  8. Third-order TRANSPORT: A computer program for designing charged particle beam transport systems

    SciTech Connect

    Carey, D.C.; Brown, K.L.; Rothacker, F.

    1995-05-01

    TRANSPORT has been in existence in various evolutionary versions since 1963. The present version of TRANSPORT is a first-, second-, and third-order matrix multiplication computer program intended for the design of static-magnetic beam transport systems. This report discusses the following topics on TRANSPORT: Mathematical formulation of TRANSPORT; input format for TRANSPORT; summaries of TRANSPORT elements; preliminary specifications; description of the beam; physical elements; other transformations; assembling beam lines; operations; variation of parameters for fitting; and available constraints -- the FIT command.

  9. Road Transportable Analytical Laboratory (RTAL) system

    SciTech Connect

    Finger, S.M.

    1995-12-01

    U.S. Department of Energy (DOE) facilities around the country have, over the years, become contaminated with radionuclides and a range of organic and inorganic wastes. Many of the DOE sites encompass large land areas and were originally sited in relatively unpopulated regions of the country to minimize risk to surrounding populations. In addition, wastes were sometimes stored underground at the sites in 55-gallon drums, wood boxes or other containers until final disposal methods could be determined. Over the years, these containers have deteriorated, releasing contaminants into the surrounding environment. This contamination has spread, in some cases polluting extensive areas. Remediation of these sites requires extensive sampling to determine the extent of the contamination, to monitor clean-up and remediation progress, and for post-closure monitoring of facilities. The DOE would benefit greatly if it had reliable, road transportable, fully independent laboratory systems that could perform on-site the full range of analyses required. Such systems would accelerate and thereby reduce the cost of clean-up and remediation efforts by (1) providing critical analytical data more rapidly, and (2) eliminating the handling, shipping and manpower associated with sample shipments. The goal of the Road Transportable Analytical Laboratory (RTAL) Project is the development and demonstration of a system to meet the unique needs of the DOE for rapid, accurate analysis of a wide variety of hazardous and radioactive contaminants in soil, groundwater, and surface waters. This laboratory system has been designed to provide the field and laboratory analytical equipment necessary to detect and quantify radionuclides, organics, heavy metals and other inorganic compounds. The laboratory system consists of a set of individual laboratory modules deployable independently or as an interconnected group to meet each DOE site`s specific needs.

  10. Innovative technology summary report: Transportable vitrification system

    SciTech Connect

    1998-09-01

    At the end of the cold war, many of the Department of Energy`s (DOE`s) major nuclear weapons facilities refocused their efforts on finding technically sound, economic, regulatory compliant, and stakeholder acceptable treatment solutions for the legacy of mixed wastes they had produced. In particular, an advanced stabilization process that could effectively treat the large volumes of settling pond and treatment sludges was needed. Based on this need, DOE and its contractors initiated in 1993 the EM-50 sponsored development effort required to produce a deployable mixed waste vitrification system. As a consequence, the Transportable Vitrification System (TVS) effort was undertaken with the primary requirement to develop and demonstrate the technology and associated facility to effectively vitrify, for compliant disposal, the applicable mixed waste sludges and solids across the various DOE complex sites. After 4 years of development testing with both crucible and pilot-scale melters, the TVS facility was constructed by Envitco, evaluated and demonstrated with surrogates, and then successfully transported to the ORNL ETTP site and demonstrated with actual mixed wastes in the fall of 1997. This paper describes the technology, its performance, the technology applicability and alternatives, cost, regulatory and policy issues, and lessons learned.

  11. Road Transportable Analytical Laboratory (RTAL) system

    SciTech Connect

    Finger, S.M.

    1995-04-01

    U.S. Department of Energy (DOE) facilities around the country have, over the years, become contaminated with radionuclides and a range of organic and inorganic wastes. Many of the DOE sites encompass large land areas and were originally sited in relatively unpopulated regions of the country to minimize risk to surrounding populations. In addition, wastes were sometimes stored underground at the sites in 55-gallon drums, wood boxes or other containers until final disposal methods could be determined. Over the years, these containers have deteriorated, releasing contaminants into the surrounding environment. This contamination has spread, in some cases polluting extensive areas. The DOE would benefit greatly if it had reliable, road transportable, fully independent laboratory systems that could perform on-site the full range of analyses required. The goal of the Road Transportable Analytical Laboratory (RTAL) project is the development and demonstration of a system to meet the unique needs of the DOE for rapid, accurate analysis of a wide variety of hazardous and radioactive contaminants in soils, ground water and surface waters. This document describes the requirements for such a laboratory.

  12. Transport systems research vehicle color display system operations manual

    NASA Technical Reports Server (NTRS)

    Easley, Wesley C.; Johnson, Larry E.

    1989-01-01

    A recent upgrade of the Transport Systems Research Vehicle operated by the Advanced Transport Operating Systems Program Office at the NASA Langley Research Center has resulted in an all-glass panel in the research flight deck. Eight ARINC-D size CRT color displays make up the panel. A major goal of the display upgrade effort was ease of operation and maintenance of the hardware while maintaining versatility needed for flight research. Software is the key to this required versatility and will be the area demanding the most detailed technical design expertise. This document is is intended to serve as a single source of quick reference information needed for routine operation and system level maintenance. Detailed maintenance and modification of the display system will require specific design documentation and must be accomplished by individuals with specialized knowledge and experience.

  13. Sensor system for fuel transport vehicle

    DOEpatents

    Earl, Dennis Duncan; McIntyre, Timothy J.; West, David L.

    2016-03-22

    An exemplary sensor system for a fuel transport vehicle can comprise a fuel marker sensor positioned between a fuel storage chamber of the vehicle and an access valve for the fuel storage chamber of the vehicle. The fuel marker sensor can be configured to measure one or more characteristics of one or more fuel markers present in the fuel adjacent the sensor, such as when the marked fuel is unloaded at a retail station. The one or more characteristics can comprise concentration and/or identity of the one or more fuel markers in the fuel. Based on the measured characteristics of the one or more fuel markers, the sensor system can identify the fuel and/or can determine whether the fuel has been adulterated after the marked fuel was last measured, such as when the marked fuel was loaded into the vehicle.

  14. A study of characteristics of intercity transportation systems. Phase 1: Definition of transportation comparison methodology

    NASA Technical Reports Server (NTRS)

    English, J. M.; Smith, J. L.; Lifson, M. W.

    1978-01-01

    The objectives of this study are: (1) to determine a unified methodological framework for the comparison of intercity passenger and freight transportation systems; (2) to review the attributes of existing and future transportation systems for the purpose of establishing measures of comparison. These objectives were made more specific to include: (1) development of a methodology for comparing long term transportation trends arising from implementation of various R&D programs; (2) definition of value functions and attribute weightings needed for further transportation goals.

  15. Air support facilities. [interface between air and surface transportation systems

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Airports are discussed in terms of the interface between the ground and air for transportation systems. The classification systems, design, facilities, administration, and operations of airports are described.

  16. Convective heat transport in geothermal systems

    SciTech Connect

    Lippmann, M.J.; Bodvarsson, G.S.

    1986-08-01

    Most geothermal systems under exploitation for direct use or electrical power production are of the hydrothermal type, where heat is transferred essentially by convection in the reservoir, conduction being secondary. In geothermal systems, buoyancy effects are generally important, but often the fluid and heat flow patterns are largely controlled by geologic features (e.g., faults, fractures, continuity of layers) and location of recharge and discharge zones. During exploitation, these flow patterns can drastically change in response to pressure and temperature declines, and changes in recharge/discharge patterns. Convective circulation models of several geothermal systems, before and after start of fluid production, are described, with emphasis on different characteristics of the systems and the effects of exploitation on their evolution. Convective heat transport in geothermal fields is discussed, taking into consideration (1) major geologic features; (2) temperature-dependent rock and fluid properties; (3) fracture- versus porous-medium characteristics; (4) single- versus two-phase reservoir systems; and (5) the presence of noncondensible gases.

  17. Road Transportable Analytical Laboratory system. Phase 1

    SciTech Connect

    Finger, S.M.; Keith, V.F.; Spertzel, R.O.; De Avila, J.C.; O`Donnell, M.; Vann, R.L.

    1993-09-01

    This developmental effort clearly shows that a Road Transportable Analytical Laboratory System is a worthwhile and achievable goal. The RTAL is designed to fully analyze (radioanalytes, and organic and inorganic chemical analytes) 20 samples per day at the highest levels of quality assurance and quality control. It dramatically reduces the turnaround time for environmental sample analysis from 45 days (at a central commercial laboratory) to 1 day. At the same time each RTAL system will save the DOE over $12 million per year in sample analysis costs compared to the costs at a central commercial laboratory. If RTAL systems were used at the eight largest DOE facilities (at Hanford, Savannah River, Fernald, Oak Ridge, Idaho, Rocky Flats, Los Alamos, and the Nevada Test Site), the annual savings would be $96,589,000. The DOE`s internal study of sample analysis needs projects 130,000 environmental samples requiring analysis in FY 1994, clearly supporting the need for the RTAL system. The cost and time savings achievable with the RTAL system will accelerate and improve the efficiency of cleanup and remediation operations throughout the DOE complex.

  18. A study of characteristics of intercity transportation systems. Phase 1: Definition of transportation comparison methodology

    NASA Technical Reports Server (NTRS)

    English, J. M.; Smith, J. L.; Lifson, M. W.

    1978-01-01

    Decision making in early transportation planning must be responsive to complex value systems representing various policies and objectives. The assessment of alternative transportation concepts during the early initial phases of the system life cycle, when supportive research and technology development activities are defined, requires estimates of transportation, environmental, and socio-economic impacts throughout the system life cycle, which is a period of some 40 or 50 years. A unified methodological framework for comparing intercity passenger and freight transportation systems is described and is extended to include the comparison of long term transportation trends arising from implementation of the various R & D programs. The attributes of existing and future transportation systems are reviewed in order to establish measures for comparison, define value functions, and attribute weightings needed for comparing alternative policy actions for furthering transportation goals. Comparison criteria definitions and an illustrative example are included.

  19. Dicetyl phosphate-tetraethylenepentamine-based liposomes for systemic siRNA delivery.

    PubMed

    Asai, Tomohiro; Matsushita, Saori; Kenjo, Eriya; Tsuzuku, Takuma; Yonenaga, Norihito; Koide, Hiroyuki; Hatanaka, Kentaro; Dewa, Takehisa; Nango, Mamoru; Maeda, Noriyuki; Kikuchi, Hiroshi; Oku, Naoto

    2011-03-16

    Dicetyl phosphate-tetraethylenepentamine (DCP-TEPA) conjugate was newly synthesized and formed into liposomes for efficient siRNA delivery. Formulation of DCP-TEPA-based polycation liposomes (TEPA-PCL) complexed with siRNA was examined by performing knockdown experiments using stable EGFP-transfected HT1080 human fibrosarcoma cells and siRNA for GFP. An adequate amount of DCP-TEPA in TEPA-PCL and N/P ratio of TEPA-PCL/siRNA complexes were determined based on the knockdown efficiency. Then, the biodistribution of TEPA-PCL modified with poly(ethylene glycol) (PEG) was examined in BALB/c mice. As a result, TEPA-PCL modified with PEG6000 avoided reticuloendothelial system uptake and showed long circulation in the bloodstream. On the other hand, PEGylation of TEPA-PCL/siRNA complexes caused dissociation of a portion of the siRNA from the liposomes. However, we found that the use of cholesterol-conjugated siRNA improved the interaction between TEPA-PCL and siRNA, which allowed PEGylation of TEPA-PCL/siRNA complexes without siRNA dissociation. In addition, TEPA-PCL complexed with cholesterol-conjugated siRNA showed potent knockdown efficiency in stable luciferase-transfected B16-F10 murine melanoma cells. Finally, the biodistribution of cholesterol-conjugated siRNA formulated in PEGylated TEPA-PCL was examined by performing near-infrared fluorescence imaging in Colon26 NL-17 murine carcinoma-bearing mice. Our results showed that tumor targeting with siRNA via systemic administration was achieved by using PEGylated TEPA-PCL combined with active targeting with Ala-Pro-Arg-Pro-Gly, a peptide used for targeting angiogenic endothelium. PMID:21361311

  20. Simulation framework for intelligent transportation systems

    SciTech Connect

    Ewing, T.; Doss, E.; Hanebutte, U.; Tentner, A.

    1996-10-01

    A simulation framework has been developed for a large-scale, comprehensive, scaleable simulation of an Intelligent Transportation System (ITS). The simulator is designed for running on parallel computers and distributed (networked) computer systems, but can run on standalone workstations for smaller simulations. The simulator currently models instrumented smart vehicles with in-vehicle navigation units capable of optimal route planning and Traffic Management Centers (TMC). The TMC has probe vehicle tracking capabilities (display position and attributes of instrumented vehicles), and can provide two-way interaction with traffic to provide advisories and link times. Both the in-vehicle navigation module and the TMC feature detailed graphical user interfaces to support human-factors studies. Realistic modeling of variations of the posted driving speed are based on human factors studies that take into consideration weather, road conditions, driver personality and behavior, and vehicle type. The prototype has been developed on a distributed system of networked UNIX computers but is designed to run on parallel computers, such as ANL`s IBM SP-2, for large-scale problems. A novel feature of the approach is that vehicles are represented by autonomous computer processes which exchange messages with other processes. The vehicles have a behavior model which governs route selection and driving behavior, and can react to external traffic events much like real vehicles. With this approach, the simulation is scaleable to take advantage of emerging massively parallel processor (MPP) systems.

  1. NASA's advanced space transportation system launch vehicles

    NASA Technical Reports Server (NTRS)

    Branscome, Darrell R.

    1991-01-01

    Some insight is provided into the advanced transportation planning and systems that will evolve to support long term mission requirements. The general requirements include: launch and lift capacity to low earth orbit (LEO); space based transfer systems for orbital operations between LEO and geosynchronous equatorial orbit (GEO), the Moon, and Mars; and Transfer vehicle systems for long duration deep space probes. These mission requirements are incorporated in the NASA Civil Needs Data Base. To accomplish these mission goals, adequate lift capacity to LEO must be available: to support science and application missions; to provide for construction of the Space Station Freedom; and to support resupply of personnel and supplies for its operations. Growth in lift capacity must be time phased to support an expanding mission model that includes Freedom Station, the Mission to Planet Earth, and an expanded robotic planetary program. The near term increase in cargo lift capacity associated with development of the Shuttle-C is addressed. The joint DOD/NASA Advanced Launch System studies are focused on a longer term new cargo capability that will significantly reduce costs of placing payloads in space.

  2. Expression of Sucrose Transporter cDNAs Specifically in Companion Cells Enhances Phloem Loading and Long-Distance Transport of Sucrose but Leads to an Inhibition of Growth and the Perception of a Phosphate Limitation1[W][OPEN

    PubMed Central

    Dasgupta, Kasturi; Khadilkar, Aswad S.; Sulpice, Ronan; Pant, Bikram; Scheible, Wolf-Rüdiger; Fisahn, Joachim; Stitt, Mark; Ayre, Brian G.

    2014-01-01

    Sucrose (Suc) is the predominant form of carbon transported through the phloem from source to sink organs and is also a prominent sugar for short-distance transport. In all streptophytes analyzed, Suc transporter genes (SUTs or SUCs) form small families, with different subgroups evolving distinct functions. To gain insight into their capacity for moving Suc in planta, representative members of each clade were first expressed specifically in companion cells of Arabidopsis (Arabidopsis thaliana) and tested for their ability to rescue the phloem-loading defect caused by the Suc transporter mutation, Atsuc2-4. Sequence similarity was a poor indicator of ability: Several genes with high homology to AtSUC2, some of which have phloem-loading functions in other eudicot species, did not rescue the Atsuc2-4 mutation, whereas a more distantly related gene, ZmSUT1 from the monocot Zea mays, did restore phloem loading. Transporter complementary DNAs were also expressed in the companion cells of wild-type Arabidopsis, with the aim of increasing productivity by enhancing Suc transport to growing sink organs and reducing Suc-mediated feedback inhibition on photosynthesis. Although enhanced Suc loading and long-distance transport was achieved, growth was diminished. This growth inhibition was accompanied by increased expression of phosphate (P) starvation-induced genes and was reversed by providing a higher supply of external P. These experiments suggest that efforts to increase productivity by enhancing sugar transport may disrupt the carbon-to-P homeostasis. A model for how the plant perceives and responds to changes in the carbon-to-P balance is presented. PMID:24777345

  3. Code System To Analyze Radiological Impact From Radwaste Transportation.

    Energy Science and Technology Software Center (ESTSC)

    1988-05-01

    Version 00 RADSHIP-2 is a computer code system used to analyze the environmental impact of radwaste transportation in Taiwan. The specific transport scheme including the land transport by truck and sea transport by ship or barge were considered in the analysis for normal transport and transport accident conditions. The code combines meteorological, population, health physics, transportation, packaging and material factors and has the capability to obtain the results of the expected annual population radiation exposure,more » the expected number of annual latent cancer fatalities and the annual probability of a given number of early fatalities.« less

  4. Space transportation system solid rocket booster thrust vector control system

    NASA Technical Reports Server (NTRS)

    Verble, A. J., Jr.; Mccool, A. A.; Potter, J. H.

    1979-01-01

    The Solid Rocket Booster, Thrust Vector Control (TVC) system was designed in accordance with the following requirements: self-contained power supply, fail-safe operation, 20 flight uses after exposure to seawater landings, optimized cost, and component interchangeability. Trade studies were performed which led to the selection of a recirculating hydraulic system powered by Auxiliary Power Units (APU) which drive the hydraulic actuators and gimbal the solid rocket motor nozzle. Other approaches for the system design were studied in arriving at the recirculating hydraulic system powered by an APU. These systems must withstand the imposed environment and be usable for a minimum of 20 Space Transportation System flights with a minimum of refurbishment. The TVC system has completed the major portion of qualification and verification tests and is prepared to be cleared for the first Shuttle flight (STS-1). Substantiation data will include analytical and test data.

  5. Space Transportation System solid rocket booster thrust vector control system

    NASA Technical Reports Server (NTRS)

    Verble, A. J., Jr.; Mccool, A. A.; Potter, J. H.

    1980-01-01

    The Solid Rocket Booster, Thrust Vector Control (TVC) system was designed in accordance with the following requirements: self-contained power supply, failsafe operation, 20 flight uses after exposure to seawater landings, optimized cost, and component interchangeability. Trade studies were performed which led to the selection of a recirculating hydraulic system powered by Auxiliary Power Units (APU) which drive the hydraulic actuators and gimbal the solid rocket motor nozzle. Other approaches for the system design were studied in arriving at the recirculating hydraulic system powered by an APU. These systems must withstand the imposed environment and be usable for a minimum of 20 Space Transportation System flights with a minimum of refurbishment. The TVC system completed the required qualification and verification tests and is certified for the intended application. Substantiation data include analytical and test data.

  6. Metabolite transport and associated sugar signalling systems underpinning source/sink interactions.

    PubMed

    Griffiths, Cara A; Paul, Matthew J; Foyer, Christine H

    2016-10-01

    Metabolite transport between organelles, cells and source and sink tissues not only enables pathway co-ordination but it also facilitates whole plant communication, particularly in the transmission of information concerning resource availability. Carbon assimilation is co-ordinated with nitrogen assimilation to ensure that the building blocks of biomass production, amino acids and carbon skeletons, are available at the required amounts and stoichiometry, with associated transport processes making certain that these essential resources are transported from their sites of synthesis to those of utilisation. Of the many possible posttranslational mechanisms that might participate in efficient co-ordination of metabolism and transport only reversible thiol-disulphide exchange mechanisms have been described in detail. Sucrose and trehalose metabolism are intertwined in the signalling hub that ensures appropriate resource allocation to drive growth and development under optimal and stress conditions, with trehalose-6-phosphate acting as an important signal for sucrose availability. The formidable suite of plant metabolite transporters provides enormous flexibility and adaptability in inter-pathway coordination and source-sink interactions. Focussing on the carbon metabolism network, we highlight the functions of different transporter families, and the important of thioredoxins in the metabolic dialogue between source and sink tissues. In addition, we address how these systems can be tailored for crop improvement. PMID:27487250

  7. Safety awareness continuity in transportation and space systems

    NASA Astrophysics Data System (ADS)

    Macidull, John C.

    The paper discusses safety awareness in transportation and space systems, the roles of definitions, statistics and accident investigation in relation to transportation safety using examples of naval and commercial aircraft historical data, and the Space Shuttle Challenger investigation.

  8. Fireworthiness of transport aircraft interior systems

    NASA Technical Reports Server (NTRS)

    Parker, J. A.; Kourtides, D. A.

    1981-01-01

    The key materials question is addressed concerning the effect of interior systems on the survival of passengers and crew in the case of an uncontrolled transport aircraft fire. Technical opportunities are examined which are available through the modification of aircraft interior subsystem components, modifications that may reasonably be expected to provide improvements in aircraft fire safety. Subsystem components discussed are interior panels, seats, and windows. By virtue of their role in real fire situations and as indicated by the results of large scale simulation tests, these components appear to offer the most immediate and highest payoff possible by modifying interior materials of existing aircraft. These modifications have the potential of reducing the rate of fire growth, with a consequent reduction of heat, toxic gas, and smoke emission throughout the habitable interior of an aircraft, whatever the initial source of the fire.

  9. Fuel cell system for transportation applications

    DOEpatents

    Kumar, R.; Ahmed, S.; Krumpelt, M.; Myles, K.M.

    1993-09-28

    A propulsion system is described for a vehicle having pairs of front and rear wheels and a fuel tank. An electrically driven motor having an output shaft operatively connected to at least one of said pair of wheels is connected to a fuel cell having a positive electrode and a negative electrode separated by an electrolyte for producing dc power to operate the motor. A partial oxidation reformer is connected both to the fuel tank and to the fuel cell and receives hydrogen-containing fuel from the fuel tank and uses water and air for partially oxidizing and reforming the fuel in the presence of an oxidizing catalyst and a reforming catalyst to produce a hydrogen-containing gas. The hydrogen-containing gas is sent from the partial oxidation reformer to the fuel cell negative electrode while air is transported to the fuel cell positive electrode to produce dc power for operating the electric motor. 3 figures.

  10. Fuel cell system for transportation applications

    DOEpatents

    Kumar, Romesh; Ahmed, Shabbir; Krumpelt, Michael; Myles, Kevin M.

    1993-01-01

    A propulsion system for a vehicle having pairs of front and rear wheels and a fuel tank. An electrically driven motor having an output shaft operatively connected to at least one of said pair of wheels is connected to a fuel cell having a positive electrode and a negative electrode separated by an electrolyte for producing dc power to operate the motor. A partial oxidation reformer is connected both to the fuel tank and to the fuel cell receives hydrogen-containing fuel from the fuel tank and water and air and for partially oxidizing and reforming the fuel with water and air in the presence of an oxidizing catalyst and a reforming catalyst to produce a hydrogen-containing gas. The hydrogen-containing gas is sent from the partial oxidation reformer to the fuel cell negative electrode while air is transported to the fuel cell positive electrode to produce dc power for operating the electric motor.

  11. The air transportation/energy system

    NASA Technical Reports Server (NTRS)

    1973-01-01

    The changing pattern of transportation is discussed, and the energy intensiveness of various modes of transportation is also analyzed. Sociopsychological data affecting why people travel by air are presented, along with governmental regulation and air transportation economics. The aviation user tax structure is shown in tabular form.

  12. Determination of induction period and crystal growth mechanism of dexamethasone sodium phosphate in methanol-acetone system

    NASA Astrophysics Data System (ADS)

    Hao, Hongxun; Wang, Jingkang; Wang, Yongli

    2005-02-01

    The induction period of dexamethasone sodium phosphate at different supersaturation was experimentally determined in a methanol-acetone system. The laser monitoring observation technique was used to determine the appearance of the first nucleus in solution. The effect of solution composition on induction period was discussed. Based on classical homogeneous nucleation theory, the solid-liquid interfacial tension and surface entropy factor were calculated from the induction period data. The experimentally determined values of interfacial tension are in agreement with the theoretical values predicted by the Mersmann equation. It was found that the nucleus of dexamethasone sodium phosphate grows continuously in pure methanol and turns from continuous growth to birth and spread growth with increasing acetone content in a methanol-acetone mixture.

  13. Continuous Culture of Rhodotorula rubra: Kinetics of Phosphate-Arsenate Uptake, Inhibition, and Phosphate-Limited Growth

    PubMed Central

    Button, D. K.; Dunker, Sally S.; Morse, M. L.

    1973-01-01

    The pink yeast Rhodotorula rubra of marine origin was found to be capable of extended growth at very low phosphate concentrations (K0.5 = 10.8 nm). Average intracellular phosphate concentrations, based on isotope exchange techniques, were 15 to 200 nm, giving concentration gradients across the cell envelope of about 106. Sensitivity to metabolic inhibitors occurred at micromolar concentrations. Inability of the phosphate transport system, Ks = 0.5 to 2.8 μm, Vmax = 55 μmoles per g of cells per min, to discriminate against arsenate transport led to arsenate toxicity at 1 to 10 nm, whereas environmental arsenate levels are reportedly much higher. Phosphate competitively prevented arsenate toxicity. The Ki for phosphate inhibition of arsenate uptake was 0.7 to 1.2 μm. Phosphate uptake experiments showed that maximal growth rates could be achieved with approximately 4% of the total phosphate-arsenate transport system. Organisms adapted to a range both of concentration of NaCl and of pH. Maximal affinity for phosphate occurred at pH 4 and at low concentrations of NaCl; however, Vmax for phosphate transport was little affected. Maximal specific growth rates on minimal medium were consistent in batch culture but gradually increased to the much higher rates found with yeast extract media when the population was subjected to long-term continuous culture with gradually increasing dilution rates. Phosphate initial uptake rates that were in agreement with the steady-state flux in continuous culture were obtained by using organisms and medium directly from continuous culture. This procedure resulted in rates about 500 times greater than one in which harvested batch-grown cells were used. Discrepancies between values found and those reported in the literature for other organisms were even larger. Growth could not be sustained below a threshold phosphate concentration of 3.4 nm. Such thresholds are explained in terms of a system where growth rate is set by intracellular

  14. Argonne simulation framework for intelligent transportation systems

    SciTech Connect

    Ewing, T.; Doss, E.; Hanebutte, U.; Canfield, T.; Brown-VanHoozer, A.; Tentner, A.

    1996-04-01

    A simulation framework has been developed which defines a high-level architecture for a large-scale, comprehensive, scalable simulation of an Intelligent Transportation System (ITS). The simulator is designed to run on parallel computers and distributed (networked) computer systems; however, a version for a stand alone workstation is also available. The ITS simulator includes an Expert Driver Model (EDM) of instrumented ``smart`` vehicles with in-vehicle navigation units. The EDM is capable of performing optimal route planning and communicating with Traffic Management Centers (TMC). A dynamic road map data base is sued for optimum route planning, where the data is updated periodically to reflect any changes in road or weather conditions. The TMC has probe vehicle tracking capabilities (display position and attributes of instrumented vehicles), and can provide 2-way interaction with traffic to provide advisories and link times. Both the in-vehicle navigation module and the TMC feature detailed graphical user interfaces that includes human-factors studies to support safety and operational research. Realistic modeling of variations of the posted driving speed are based on human factor studies that take into consideration weather, road conditions, driver`s personality and behavior and vehicle type. The simulator has been developed on a distributed system of networked UNIX computers, but is designed to run on ANL`s IBM SP-X parallel computer system for large scale problems. A novel feature of the developed simulator is that vehicles will be represented by autonomous computer processes, each with a behavior model which performs independent route selection and reacts to external traffic events much like real vehicles. Vehicle processes interact with each other and with ITS components by exchanging messages. With this approach, one will be able to take advantage of emerging massively parallel processor (MPP) systems.

  15. ESTIMATION OF HYDROLYSIS RATE CONSTANTS OF CARBOXYLIC ACID ESTER AND PHOSPHATE ESTER COMPOUNDS IN AQUEOUS SYSTEMS FROM MOLECULAR STRUCTURE BY SPARC

    EPA Science Inventory

    SPARC (SPARC Performs Automated Reasoning in Chemistry) chemical reactivity models were extended to calculate hydrolysis rate constants for carboxylic acid ester and phosphate ester compounds in aqueous non- aqueous and systems strictly from molecular structure. The energy diffe...

  16. Practical Implications from Observed Lead Pipe Scale Mineralogy in a Blended Phosphate Treated System - slides

    EPA Science Inventory

    Many water utilities in the United States rely on the addition of phosphate-based corrosion inhibitors to optimize their corrosion control and comply with requirements of the Lead and Copper Rule. Orthophosphate is used on the theory of forming low solubility Pb(II)-orthophosphat...

  17. Systematic Development of Intelligent Systems for Public Road Transport

    PubMed Central

    García, Carmelo R.; Quesada-Arencibia, Alexis; Cristóbal, Teresa; Padrón, Gabino; Alayón, Francisco

    2016-01-01

    This paper presents an architecture model for the development of intelligent systems for public passenger transport by road. The main objective of our proposal is to provide a framework for the systematic development and deployment of telematics systems to improve various aspects of this type of transport, such as efficiency, accessibility and safety. The architecture model presented herein is based on international standards on intelligent transport system architectures, ubiquitous computing and service-oriented architecture for distributed systems. To illustrate the utility of the model, we also present a use case of a monitoring system for stops on a public passenger road transport network. PMID:27438836

  18. Systematic Development of Intelligent Systems for Public Road Transport.

    PubMed

    García, Carmelo R; Quesada-Arencibia, Alexis; Cristóbal, Teresa; Padrón, Gabino; Alayón, Francisco

    2016-01-01

    This paper presents an architecture model for the development of intelligent systems for public passenger transport by road. The main objective of our proposal is to provide a framework for the systematic development and deployment of telematics systems to improve various aspects of this type of transport, such as efficiency, accessibility and safety. The architecture model presented herein is based on international standards on intelligent transport system architectures, ubiquitous computing and service-oriented architecture for distributed systems. To illustrate the utility of the model, we also present a use case of a monitoring system for stops on a public passenger road transport network. PMID:27438836

  19. Inhibition of phosphate transport in rat heart mitochondria by 3'-azido-3'-deoxythymidine due to stimulation of superoxide anion mitochondrial production.

    PubMed

    Valenti, Daniela; Atlante, Anna; Barile, Maria; Passarella, Salvatore

    2002-07-15

    In order to gain some insight into the mechanism by which 3'-azido-3'-deoxythymidine (AZT) damages mitochondria, we investigated whether externally added AZT can stimulate reactive oxygen species (ROS) production by rat heart mitochondria (RHM). An increase in superoxide anion ((O(2)(.-)) production was measured in RHM added with AZT, by using a photometrically method which allows an early O(2)(.-) detection by following the absorbance increase at 550 nm due to the ferricytochrome c reduction. Such an increase was found to be prevented from externally added superoxide dismutase. The stimulation of O(2)(.-) mitochondrial production induced by AZT was found to occur under conditions in which mitochondrial oxygen consumption was prevented by both inhibitors of electron flow and ATP synthesis. Since ROS can cause mitochondrial carrier impairment, we investigated whether AZT can affect mitochondrial permeability in virtue of its capability to stimulate ROS production. In this regard, we studied the transport of phosphate (P(i)), by measuring the mitochondrial shrinkage that takes place as a result of P(i) uptake by RHM previously swollen in a calcium acetate medium. As a result of the AZT-dependent O(2)(.-) production, uncompetitive inhibition of the rate of P(i) transport in RHM was found (K(i) of about 10 microM), consistently, such an inhibition was found to prevent by certain known ROS scavengers, i.e. superoxide dismutase, the antioxidant Vitamin C and reduced gluthatione. PMID:12123740

  20. National Space Transportation Systems Program mission report

    NASA Technical Reports Server (NTRS)

    Collins, M. A., Jr.; Aldrich, A. D.; Lunney, G. S.

    1984-01-01

    The 515-41B National Space Transportation Systems Program Mission Report contains a summary of the major activities and accomplishments of the sixth operational Shuttle flight and fourth flight of the OV-099 vehicle, Challenger. Since this flight was the first to land at Kennedy Space Center, the vehicle was towed directly to the OPF (Orbiter Processing Facility) where preparations for flight STS-41C, scheduled for early April 1984, began immediately. The significant problems that occurred during STS-41B are summarized and a problem tracking list that is a complete list of all problems that occurred during the flight is given. None of the problems will affect the STS 41C flight. The major objectives of flight STS-41B were to successfully deploy the Westar satellite and the Indonesian Communications Satellite-B2 (PALAPA-B2); to evaluate the MMU (Manned Maneuvering Unit) support for EVA (Extravehicular Activities); to exercise the MFR (Manipulator Foot Restraint); to demonstrate a closed loop rendezvous; and to operate the M.R (Monodisperse Latex Reactor), the ACES (Acoustic Containerless Experiment System) and the IEF (Isoelectric Focusing) in cabin experiments; and to obtain photographs with the Cinema 360 Cameras.

  1. Advanced space transportation systems, BARGOUZIN booster

    NASA Astrophysics Data System (ADS)

    Prampolini, Marco; Louaas, Eric; Prel, Yves; Kostromin, Sergey; Panichkin, Nickolay; Sumin, Yuriy; Osin, Mikhail; Iranzo-Greus, David; Rigault, Michel; Beaurain, André; Couteau, Jean-Noël

    2008-07-01

    In the framework of Advanced Space Transportation Systems Studies sponsored by CNES in 2006, a study called "BARGOUZIN" was performed by a joint team led by ASTRIUM ST and TSNIIMASH. Beyond these leaders, the team comprised MOLNIYA, DASSAULT AVIATION and SNECMA as subcontractors. The "BARGOUZIN" concept is a liquid fuelled fly-back booster (LFBB), mounted on the ARIANE 5 central core stage in place of the current solid rocket booster. The main originality of the concept lies in the fact that the "BARGOUZIN" features a cluster of VULCAIN II engines, similar to the one mounted on the central core stage of ARIANE 5. An astute permutation strategy, between the booster engines and central core engine is expected to lead to significant cost reductions. The following aspects were addressed during the preliminary system study: engine number per booster trade-off/abort scenario analysis, aerodynamic consolidation, engine reliability, ascent controllability, ground interfaces separation sequence analysis, programmatics. These topics will be briefly presented and synthesized in this paper, giving an overview of the credibility of the concept.

  2. NANONIS TRAMEA - A Quantum Transport Measurement System

    NASA Astrophysics Data System (ADS)

    Kampen, Thorsten; Thissen, Andreas; Schaff, Oliver; Pioda, Alessandro

    Nanonis Tramea is a quantum leap with respect to increased speed for transport measurements taking research onto a new level. Measurements which took several hours in the past can now be done in minutes without compromising signal quality. Tramea uses its fast, high-resolution, high-precision and ultra-low-noise outputs and inputs to generate and acquire up to 20000 data points per second on 24 channels in parallel. This is not only up to 1000 x faster than typical measurement systems but it is also time deterministic with highest precision. Here, the time separation between points is constant so that artefacts caused by unequal point spacings in non-deterministic measurement systems are avoided. The emphasis here is the real-time relation. Tramea comes with a built-in interface which allows for control of the instruments' basic functions from any programming environment. For users requiring more functionality and higher speeds a full-featured LabVIEW-based programming interface or scripting module are available as add-on modules. Due to the modularity and flexibility of the hardware and software architecture of Tramea upgrades with standardized add-on modules are possible. Non-standard requests can still be handled by the various programming options.

  3. Biosynthesis of Dolichyl Phosphate

    PubMed Central

    Hopp, H. Esteban; Daleo, Gustavo R.; Romero, Pedro A.; Lezica, Rafael Pont

    1978-01-01

    This is the first report not only on the presence of polyprenyl phosphates and their site of synthesis in algae, but also on the formation of their sugar derivatives in this system. A glucose acceptor lipid was isolated from the nonphotosynthetic alga Prototheca zopfii. The lipid was acidic and resistant to mild acid and alkaline treatments. The glucosylated lipid was labile to mild acid hydrolysis and resistant to phenol treatment and catalytic hydrogenation, as dolichyl phosphate glucose is. These results are consistent with the properties of an α-saturated polyprenyl phosphate. The polyprenylic nature of the lipid was confirmed by biosynthesis from radioactive mevalonate. The [14C]lipid had the same chromatographic properties as dolichyl phosphate in DEAE-cellulose and Sephadex LH-20. Strong alkaline treatment and enzymic hydrolysis liberated free alcohols with chain lengths ranging from C90 to C105, C95 and C100 being the most abundant molecular forms. The glucose acceptor activity of the biosynthesized polyprenyl phosphate was confirmed. The ability of different subcellular fractions to synthesize dolichyl phosphate was studied. Mitochondria and the Golgi apparatus were the sites of dolichyl phosphate synthesis from mevalonate. PMID:16660269

  4. The Two-Component System PhoPR of Clostridium acetobutylicum Is Involved in Phosphate-Dependent Gene Regulation ▿

    PubMed Central

    Fiedler, Tomas; Mix, Maren; Meyer, Uta; Mikkat, Stefan; Glocker, Michael O.; Bahl, Hubert; Fischer, Ralf-Jörg

    2008-01-01

    The phoPR gene locus of Clostridium acetobutylicum ATCC 824 comprises two genes, phoP and phoR. Deduced proteins are predicted to represent a response regulator and sensor kinase of a phosphate-dependent two-component regulatory system. We analyzed the expression patterns of phoPR in Pi-limited chemostat cultures and in response to Pi pulses. A basic transcription level under high-phosphate conditions was shown, and a significant increase in mRNA transcript levels was found when external Pi concentrations dropped below 0.3 mM. In two-dimensional gel electrophoresis experiments, a 2.5-fold increase in PhoP was observed under Pi-limiting growth conditions compared to growth with an excess of Pi. At least three different transcription start points for phoP were determined by primer extension analyses. Proteins PhoP and an N-terminally truncated *PhoR were individually expressed heterologously in Escherichia coli and purified. Autophosphorylation of *PhoR and phosphorylation of PhoP were shown in vitro. Electromobility shift assays proved that there was a specific binding of PhoP to the promoter region of the phosphate-regulated pst operon of C. acetobutylicum. PMID:18689481

  5. Road transportable analytical laboratory (RTAL) system

    SciTech Connect

    Finger, S.M.

    1996-12-31

    Remediation of DOE contaminated areas requires extensive sampling and analysis. Reliable, road transportable, fully independent laboratory systems that could perform on-site a full range of analyses meeting high levels of quality assurance and control, would accelerate and thereby reduce the cost of cleanup and remediation efforts by (1) providing critical analytical data more rapidly, and (2) eliminating the handling, shipping, and manpower associated with sample shipments. Goals of RTAL are to meet the needs of DOE for rapid, accurate analysis of a wide variety of hazardous and radioactive contaminants in soil, groundwater, and surface waters. The system consists of a set of individual laboratory modules deployable independently or together, to meet specific site needs: radioanalytical lab, organic chemical analysis lab, inorganic chemical analysis lab, aquatic biomonitoring lab, field analytical lab, robotics base station, decontamination/sample screening module, and operations control center. Goal of this integrated system is a sample throughput of 20 samples/day, providing a full range of accurate analyses on each sample within 16 h (after sample preparation), compared with the 45- day turnaround time in commercial laboratories. A prototype RTAL consisting of 5 modules was built and demonstrated at Fernald(FEMP)`s OU-1 Waste Pits, during the 1st-3rd quarters of FY96 (including the `96 Blizzard). All performance and operational goals were met or exceeded: as many as 50 sample analyses/day were achieved, depending on the procedure, sample turnaround times were 50-67% less than FEMP`s best times, and RTAL costs were projected to be 30% less than FEMP costs for large volume analyses in fixed laboratories.

  6. The SIMPSONS project: An integrated Mars transportation system

    NASA Technical Reports Server (NTRS)

    Kaplan, Matthew; Carlson, Eric; Bradfute, Sherie; Allen, Kent; Duvergne, Francois; Hernandez, Bert; Le, David; Nguyen, Quan; Thornhill, Brett

    1992-01-01

    In response to the Request for Proposal (RFP) for an integrated transportation system network for an advanced Martian base, Frontier Transportation Systems (FTS) presents the results of the SIMPSONS project (Systems Integration for Mars Planetary Surface Operations Networks). The following topics are included: the project background, vehicle design, future work, conclusions, management status, and cost breakdown. The project focuses solely on the surface-to-surface transportation at an advanced Martian base.

  7. The SIMPSONS project: An integrated Mars transportation system

    NASA Astrophysics Data System (ADS)

    Kaplan, Matthew; Carlson, Eric; Bradfute, Sherie; Allen, Kent; Duvergne, Francois; Hernandez, Bert; Le, David; Nguyen, Quan; Thornhill, Brett

    In response to the Request for Proposal (RFP) for an integrated transportation system network for an advanced Martian base, Frontier Transportation Systems (FTS) presents the results of the SIMPSONS project (Systems Integration for Mars Planetary Surface Operations Networks). The following topics are included: the project background, vehicle design, future work, conclusions, management status, and cost breakdown. The project focuses solely on the surface-to-surface transportation at an advanced Martian base.

  8. Integrated mass transportation system study/definition/implementation program definition

    NASA Technical Reports Server (NTRS)

    Ransone, R. K.; Deptula, D. A.; Yorke, G. G.

    1975-01-01

    Specific actions needed to plan and effect transportation system improvements are identified within the constraints of limited financial, energy and land use resources, and diverse community requirements. A specific program is described which would develop the necessary generalized methodology for devising improved transportation systems and evaluate them against specific criteria for intermodal and intramodal optimization. A consistent, generalized method is provided for study and evaluation of transportation system improvements.

  9. Modelling of calcium phosphates

    NASA Astrophysics Data System (ADS)

    Calderin Hidalgo, Lazaro Juan

    This work is a contribution to a large scale joint experimental and theoretical effort to understand the biological properties of silicon doped calcium phosphates undertaken by Queen's University and Millenium Biologix Corp. We have modeled calcium phosphates and silicon doped calcium phosphates in close relation to experiment in order to study possible location of silicon in the lattice. Density functional theory has been used to study the structural and dynamical properties of small systems of calcium phosphates to gain preliminary information on phosphates and the performance of the theoretical methods. The same methods were used to investigate structural and electronic properties of larger scale calcium phosphate systems, while a classical shell model was developed to investigate the dynamical properties of such large and complex systems. In the context of the shell model a method was devised to calculate the dynamical matrix corrected for the long range Coulomb interaction in the long wave length limit. It was necessary also to develop a theoretical expression for the dielectric function in the context of the shell model. Infrared spectra and thermal parameters were calculated based on these methods. We also propose some directions for future research.

  10. Concept of Integrated Information Systems of Rail Transport

    NASA Astrophysics Data System (ADS)

    Siergiejczyk, Mirosław; Gago, Stanisław

    This paper will present a need to create integrated information systems of the rail transport and their links with other means of public transportation. IT standards will be discussed that are expected to create the integrated information systems of the rail transport. Also the main tasks will be presented of centralized information systems, the concept of their architecture, business processes and their implementation as well as the proposed measures to secure data. A method shall be proposed to implement a system to inform participants of rail transport in Polish conditions.

  11. A Functional-Phylogenetic Classification System for Transmembrane Solute Transporters

    PubMed Central

    Saier, Milton H.

    2000-01-01

    A comprehensive classification system for transmembrane molecular transporters has been developed and recently approved by the transport panel of the nomenclature committee of the International Union of Biochemistry and Molecular Biology. This system is based on (i) transporter class and subclass (mode of transport and energy coupling mechanism), (ii) protein phylogenetic family and subfamily, and (iii) substrate specificity. Almost all of the more than 250 identified families of transporters include members that function exclusively in transport. Channels (115 families), secondary active transporters (uniporters, symporters, and antiporters) (78 families), primary active transporters (23 families), group translocators (6 families), and transport proteins of ill-defined function or of unknown mechanism (51 families) constitute distinct categories. Transport mode and energy coupling prove to be relatively immutable characteristics and therefore provide primary bases for classification. Phylogenetic grouping reflects structure, function, mechanism, and often substrate specificity and therefore provides a reliable secondary basis for classification. Substrate specificity and polarity of transport prove to be more readily altered during evolutionary history and therefore provide a tertiary basis for classification. With very few exceptions, a phylogenetic family of transporters includes members that function by a single transport mode and energy coupling mechanism, although a variety of substrates may be transported, sometimes with either inwardly or outwardly directed polarity. In this review, I provide cross-referencing of well-characterized constituent transporters according to (i) transport mode, (ii) energy coupling mechanism, (iii) phylogenetic grouping, and (iv) substrates transported. The structural features and distribution of recognized family members throughout the living world are also evaluated. The tabulations should facilitate familial and functional

  12. ArfGAP3 regulates the Transport of Cation-Independent Mannose 6-phosphate Receptor in the post-Golgi compartment

    PubMed Central

    Shiba, Yoko; Kametaka, Satoshi; Waguri, Satoshi; Presley, John F.; Randazzo, Paul Agostino

    2013-01-01

    Summary ArfGAPs are known to be involved in cargo sorting in COPI transport. However, the role of ArfGAPs in post-Golgi membrane traffic has not been defined. To determine the function of ArfGAPs in post-Golgi traffic, we used siRNA to examine each of 25 ArfGAPs for effects on cation-independent mannose 6-phosphate receptor (CIMPR) localization. We found that down-regulation of ArfGAP3 resulted in the peripheral localization of CIMPR. The effect was specific for ArfGAP3 and dependent on its GAP activity, because the phenotype was rescued by ArfGAP3 but not by ArfGAP1, ArfGAP2 or the GAP domain mutants of ArfGAP3. ArfGAP3 localized to the trans-Golgi network and early endosomes. In cells with reduced expression of ArfGAP3, Cathepsin D maturation was slowed and its secretion was accelerated. Also retrograde transport from the endosomes to the trans-Golgi network of endogenous CIMPR, but not truncated CIMPR lacking the luminal domain, was perturbed in cells with reduced expression of ArfGAP3. Furthermore the exit of epidermal growth factor receptor (EGFR) from the early endosomes and degradation of EGFR after EGF stimulation was slowed in cells with reduced expression of ArfGAP3. ArfGAP3 associates with Golgi-localized, γ-ear-containing, ADP-ribosylation factor binding proteins (GGAs), and ArfGAP3 knockdown reduces membrane association of GGAs. A possible mechanism explaining our results is that ArfGAP3 regulates transport from early endosomes to late endosomes. We suggest a model in which ArfGAP3 regulates Golgi association of GGA clathrin adaptors. PMID:24076238

  13. The 5-phosphatase OCRL mediates retrograde transport of the mannose 6-phosphate receptor by regulating a Rac1-cofilin signalling module

    PubMed Central

    van Rahden, Vanessa A.; Brand, Kristina; Najm, Juliane; Heeren, Joerg; Pfeffer, Suzanne R.; Braulke, Thomas; Kutsche, Kerstin

    2012-01-01

    Mutations in the OCRL gene encoding the phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) 5-phosphatase OCRL cause Lowe syndrome (LS), which is characterized by intellectual disability, cataracts and selective proximal tubulopathy. OCRL localizes membrane-bound compartments and is implicated in intracellular transport. Comprehensive analysis of clathrin-mediated endocytosis in fibroblasts of patients with LS did not reveal any difference in trafficking of epidermal growth factor, low density lipoprotein or transferrin, compared with normal fibroblasts. However, LS fibroblasts displayed reduced mannose 6-phosphate receptor (MPR)-mediated re-uptake of the lysosomal enzyme arylsulfatase B. In addition, endosome-to-trans Golgi network (TGN) transport of MPRs was decreased significantly, leading to higher levels of cell surface MPRs and their enrichment in enlarged, retromer-positive endosomes in OCRL-depleted HeLa cells. In line with the higher steady-state concentration of MPRs in the endosomal compartment in equilibrium with the cell surface, anterograde transport of the lysosomal enzyme, cathepsin D was impaired. Wild-type OCRL counteracted accumulation of MPR in endosomes in an activity-dependent manner, suggesting that PI(4,5)P2 modulates the activity state of proteins regulated by this phosphoinositide. Indeed, we detected an increased amount of the inactive, phosphorylated form of cofilin and lower levels of the active form of PAK3 upon OCRL depletion. Levels of active Rac1 and RhoA were reduced or enhanced, respectively. Overexpression of Rac1 rescued both enhanced levels of phosphorylated cofilin and MPR accumulation in enlarged endosomes. Our data suggest that PI(4,5)P2 dephosphorylation through OCRL regulates a Rac1-cofilin signalling cascade implicated in MPR trafficking from endosomes to the TGN. PMID:22907655

  14. Transportation system requirements document. Revision 1 DCN01. Supplement

    SciTech Connect

    1995-05-01

    The original Transportation System Requirements Document described the functions to be performed by and the technical requirements for the Transportation System to transport spent nuclear fuel (SNF) and high-level radioactive waste (HLW) from Purchaser and Producer sites to a Civilian Radioactive Waste Management System (CRWMS) site, and between CRWMS sites. The purpose of that document was to define the system-level requirements. These requirements include design and operations requirements to the extent they impact on the development of the physical segments of Transportation. The document also presented an overall description of Transportation, its functions, its segments, and the requirements allocated to the segments and the system-level interfaces with Transportation. This revision of the document contains only the pages that have been modified.

  15. Pore-Scale Evaluation of Uranyl Phosphate Precipitation in a Model Groundwater System

    SciTech Connect

    Fanizza, Michael F.; Yoon, Hongkyu; Zhang, Changyong; Oostrom, Martinus; Wietsma, Thomas W.; Hess, Nancy J.; Bowden, Mark E.; Strathmann, Timothy J.; Finneran, Kevin T.; Werth, Charles J.

    2013-02-01

    The abiotic precipitation of uranium (U(VI)) was evaluated in a microfluidic pore network (i.e. micromodel) to assess the efficacy of using a phosphate amendment to immobilize uranium in groundwater. U(VI) was mixed transverse to the direction of flow with hydrogen phosphate (HPO42-), in the presence or absence of calcium (Ca2+) or sulfate (SO42-), in order to identify precipitation rates, morphology and types of minerals formed, and effects of mineral precipitates on pore blockage. Precipitation occurred over the time scale of hours to days. Relative to when only U(VI) and HPO42- were present, precipitation rates were 2.3X slower when SO42- was present, and 1.4X faster when Ca2+ was present; larger crystals formed in the presence of SO42-. Raman backscattering spectroscopy and micro X-ray diffraction (μ-XRD) results both showed that the only mineral precipitated was chernikovite, UO2HPO4•4H2O; energy dispersive x-ray spectroscopy results indicate that Ca and S are not incorporated into the chernikovite lattice. A pore scale model was developed, and simulation results of saturation ratio (SR=Q/Ksp) suggest that chernikovite is the least thermodynamically favored mineral to precipitate (0phosphate and Na-Autunite (13105). Fluorescent tracer studies and laser confocal microscopy images showed that densely aggregated precipitates blocked pores and reduced permeability. The results suggest that uranium precipitation with phosphate as chernikovite is rapid on the time scale of remediation for the conditions considered, and can block pores, alter fluid flow paths, and potentially limit mixing and precipitation.

  16. Highly reusable space transportation system study

    SciTech Connect

    Haney, J.W.

    1997-01-01

    To significantly increase demand for launch services by stimulating existing and planned markets as well as enabling new markets, the cost to orbit needs to be reduced a factor of ten below projected Reusable Launch Vehicle (RLV) goals. This will place the recurring operations cost around {dollar_sign}200 per payload pound to low earth orbit (LEO). Methods for reducing the cost include: increasing relative vehicle performance, increasing vehicle reusability, and decreasing recurring operations. A study was conducted for NASA in support of its Highly Reusable Space Transportation (HRST) initiative to identify for further assessment and development, those launch strategies that hold the greatest potential with respect to meeting this goal. During this study a number of candidate strategies were evaluated associated with access to space. Both technical and cost trades were performed, and concluded that there are two airbreathing propulsion concepts utilizing launch assist that appear promising in achieving the HRST-cost goals. These concepts employ both turbine based combine cycle (TBCC) and rocket based combine cycle (RBCC) propulsion systems. The launch assist selected uses electromagnetic propulsion and a guideway to provide both delta velocity and altitude. A first order investigation of system level requirements associated with HRST launch assist for a magnetically launched vehicle including guideway concept and requirements as well as magnetic levitation and propulsion concepts and requirements were also conducted. This study concluded that the HRST goals of total recurring operations cost of {dollar_sign}200 per payload pound to Low Earth Orbit based on a ten year operational period were feasible if the required technology was matured. The most promising concept to achieve these goals is based on a RBCC powered vehicle with electromagnetic launch assist. {copyright} {ital 1997 American Institute of Physics.}

  17. A Segway RMP-based robotic transport system

    NASA Astrophysics Data System (ADS)

    Nguyen, Hoa G.; Kogut, Greg; Barua, Ripan; Burmeister, Aaron; Pezeshkian, Narek; Powell, Darren; Farrington, Nathan; Wimmer, Matt; Cicchetto, Brett; Heng, Chana; Ramirez, Velia

    2004-12-01

    In the area of logistics, there currently is a capability gap between the one-ton Army robotic Multifunction Utility/Logistics and Equipment (MULE) vehicle and a soldier"s backpack. The Unmanned Systems Branch at Space and Naval Warfare Systems Center (SPAWAR Systems Center, or SSC), San Diego, with the assistance of a group of interns from nearby High Tech High School, has demonstrated enabling technologies for a solution that fills this gap. A small robotic transport system has been developed based on the Segway Robotic Mobility Platform (RMP). We have demonstrated teleoperated control of this robotic transport system, and conducted two demonstrations of autonomous behaviors. Both demonstrations involved a robotic transporter following a human leader. In the first demonstration, the transporter used a vision system running a continuously adaptive mean-shift filter to track and follow a human. In the second demonstration, the separation between leader and follower was significantly increased using Global Positioning System (GPS) information. The track of the human leader, with a GPS unit in his backpack, was sent wirelessly to the transporter, also equipped with a GPS unit. The robotic transporter traced the path of the human leader by following these GPS breadcrumbs. We have additionally demonstrated a robotic medical patient transport capability by using the Segway RMP to power a mock-up of the Life Support for Trauma and Transport (LSTAT) patient care platform, on a standard NATO litter carrier. This paper describes the development of our demonstration robotic transport system and the various experiments conducted.

  18. The Na+-phosphate cotransport system (NaPi-II) with a cleaved protein backbone: implications on function and membrane insertion

    PubMed Central

    Kohl, Beate; Wagner, Carsten A; Huelseweh, Birgit; Busch, Andreas E; Werner, Andreas

    1998-01-01

    Renal handling of inorganic phosphate (Pi) involves a Na+-Pi cotransport system which is well conserved between vertebrates. The members of this protein family, denoted NaPi-II, share a topology with, it is thought, eight transmembrane domains. The transporter is proposed to be proteolytically cleaved within a large hydrophilic loop in vivo. The consequences of an interrupted backbone were tested by constructing cDNA clones encoding different N- (1-3 and 1-5) and C-terminal (4-8 and 6-8) complementary fragments of NaPi-II from winter flounder. When the cognate fragments were used in combination (1-3 plus 4-8; 1-5 plus 6-8) they comprised the full complement of the putative transporter domains. None of the four individual fragments or the 1-5 plus 6-8 combination when expressed in Xenopus oocytes increased Pi flux. Coexpression of fragments 1-3 plus 4-8 stimulated transport activity identical to that for expressed wild-type NaPi-II with regard to pH dependency and Km for Na+ and Pi binding; however, the maximal transport rate (vmax) was lower. Immunohistochemistry on cryosections confined the functionally active 1-3 plus 4-8 combination to the oocyte membrane. This was not the case for the 1-5 plus 6-8 combination or any of the individual fragments, all of which failed to induce fluorescence. A second immunohistochemical approach using intact oocytes allowed determination of the extracellular regions of the protein. Epitopes within the loop between transmembrane domains 3 and 4 enhanced fluorescence. Neither N- nor C-terminal tags induced fluorescence. PMID:9508800

  19. High levels of the type III inorganic phosphate transporter PiT1 (SLC20A1) can confer faster cell adhesion

    SciTech Connect

    Kongsfelt, Iben Boutrup; Byskov, Kristina; Pedersen, Lasse Ebdrup; Pedersen, Lene

    2014-08-01

    The inorganic phosphate transporter PiT1 (SLC20A1) is ubiquitously expressed in mammalian cells. We recently showed that overexpression of human PiT1 was sufficient to increase proliferation of two strict density-inhibited cell lines, murine fibroblastic NIH3T3 and pre-osteoblastic MC3T3-E1 cells, and allowed the cultures to grow to higher cell densities. In addition, upon transformation NIH3T3 cells showed increased ability to form colonies in soft agar. The cellular regulation of PiT1 expression supports that cells utilize the PiT1 levels to control proliferation, with non-proliferating cells showing the lowest PiT1 mRNA levels. The mechanism behind the role of PiT1 in increased cell proliferation is not known. We, however, found that compared to control cells, cultures of NIH3T3 cells overexpressing PiT1 upon seeding showed increased cell number after 24 h and had shifted more cells from G0/G1 to S+G2/M within 12 h, suggesting that an early event may play a role. We here show that expression of human PiT1 in NIH3T3 cells led to faster cell adhesion; this effect was not cell type specific in that it was also observed when expressing human PiT1 in MC3T3-E1 cells. We also show for NIH3T3 that PiT1 overexpression led to faster cell spreading. The final total numbers of attached cells did, however, not differ between cultures of PiT1 overexpressing cells and control cells of neither cell type. We suggest that the PiT1-mediated fast adhesion potentials allow the cells to go faster out of G0/G1 and thereby contribute to their proliferative advantage within the first 24 h after seeding. - Highlights: • Effects of elevated levels of the inorganic phosphate transporter PiT1 were studied. • The density-inhibited murine cell lines NIH3T3 and MC3T3-E1 showed faster adhesion. • NIH3T3 cells showed faster spreading. • We suggest that the faster adhesion/spreading contributes to faster proliferation.

  20. Alkali-phosphate common-ion system for synthesis of rare-earth orthophosphates

    NASA Astrophysics Data System (ADS)

    Uhrin, Robert

    Rare-earth orthophosphate crystals are interesting materials for many optical applications, because their physical properties often exceed those of currently used materials. In particular, Ce:LuPO4 is useful for positron emission tomography (PET). The most important reason why this and other rare-earth orthophosphate crystals haven't been commercialized is the absence of large crystals suitable for devices. The greatest impediment is the lack of a suitable crystal growth process. A Pb2P2 O7 solution has been used for many years to produce a complete series of lanthanide orthophosphate crystals, but this solution raises some serious environmental concerns. In addition, large crystals of a reproducible size and quality that are required for device fabrication do not result, and the crystals tend to be platy. It is generally known that a change in solution acidity or basicity affects the habit of grown crystals. Consequently, it was theorized that a potassium-based system (i. e. more basic) would result in equiaxed crystals, and such a system has been investigated in an effort to obtain a partial phase diagram for the KPO3- Lu2O 3 pseudo-binary system. Various techniques were employed to confirm a molten solution composition from which crystals can be grown. LuPO4 crystals were produced from solutions with different K2O/P2O5 ratios and varied Lu2O3 concentrations. This provided information on the preferred composition range for single phase LuPO4, as well as the solid phases expected within the range of compositions that was studied. X-ray diffraction (XRD) analysis provided a useful tool to identify the solid phases. Powder synthesis with subsequent XRD analysis was also utilized in some cases, since numerous single and mixed phosphate compounds are possible and a complete set of diffraction files is not available. Knowledge of the cerium concentration is also required in the case of Ce:LuPO4, so a K2O-CeO2-Lu2O3-P2O 5 glass was developed. Samples containing varied

  1. Solvent extraction study of the thorium nitrate, nitric acid, and tributyl phosphate-dodecane system: density and acidity relationships

    SciTech Connect

    Weinberger, A.J.; Marley, J.L.; Costanzo, D.A.

    1980-05-01

    A solvent extraction study to determine equilibrium conditions of thorium nitrate-nitric acid with 30% tributyl phosphate in normal dodecane has been completed. Experimental conditions studied were 30 to 60{sup 0}C, 0.05 to 1.5 M Th(NO{sub 3}){sub 4}, and 0.0 to 3.0 M HNO{sub 3}. The extractant concentration was constant at 30% tributyl phosphate. The equilibrium experiments have produced data which demonstrate that thorium nitrate concentration, free acid, and density are related in equilibrium behavior between the aqueous and organic phases from 30 to 60{sup 0}C in the 30% tributyl phosphate-dodecane solvent extraction system. The concentration interactions apply to both the two- and three-phase regions. A linear correlation was observed for the density (D) of the aqueous or organic phase and the concentration of thorium and free acid. The general form of the equation is D = a(C/sub Th/ + bC/sub H/) + c, where a is the slope, b is the constant, c is the intercept, and C/sub Th/ and C/sub H/ are the molar concentrations of thorium and free acid respectively. The relationship of temperature, thorium nitrate, and free acid makes possible the definitions of the boundaries between the two- and three-phase regions. This dependence, in turn, permits operational control or simulation studies of the system within the two-phase region. The data demonstrate the interactions of the components of the Thorex system and can be used to improve the mathematical description of equilibrium in the SEPHIS-Thorex computer program.

  2. Advanced transportation system study: Manned launch vehicle concepts for two way transportation system payloads to LEO

    NASA Technical Reports Server (NTRS)

    Duffy, James B.

    1993-01-01

    The purpose of the Advanced Transportation System Study (ATSS) task area 1 study effort is to examine manned launch vehicle booster concepts and two-way cargo transfer and return vehicle concepts to determine which of the many proposed concepts best meets NASA's needs for two-way transportation to low earth orbit. The study identified specific configurations of the normally unmanned, expendable launch vehicles (such as the National Launch System family) necessary to fly manned payloads. These launch vehicle configurations were then analyzed to determine the integrated booster/spacecraft performance, operations, reliability, and cost characteristics for the payload delivery and return mission. Design impacts to the expendable launch vehicles which would be required to perform the manned payload delivery mission were also identified. These impacts included the implications of applying NASA's man-rating requirements, as well as any mission or payload unique impacts. The booster concepts evaluated included the National Launch System (NLS) family of expendable vehicles and several variations of the NLS reference configurations to deliver larger manned payload concepts (such as the crew logistics vehicle (CLV) proposed by NASA JSC). Advanced, clean sheet concepts such as an F-1A engine derived liquid rocket booster (LRB), the single stage to orbit rocket, and a NASP-derived aerospace plane were also included in the study effort. Existing expendable launch vehicles such as the Titan 4, Ariane 5, Energia, and Proton were also examined. Although several manned payload concepts were considered in the analyses, the reference manned payload was the NASA Langley Research Center's HL-20 version of the personnel launch system (PLS). A scaled up version of the PLS for combined crew/cargo delivery capability, the HL-42 configuration, was also included in the analyses of cargo transfer and return vehicle (CTRV) booster concepts. In addition to strictly manned payloads, two-way cargo

  3. Transport in small and/or random systems

    SciTech Connect

    Lax, M.

    1987-05-14

    This report discusses: transport in small systems; electron-phonon interactions in quantum wells; noise in small systems; laser propagation in the atmosphere; laser-aerosol interactions; transport properties of carriers in semiconductor quantum wells; light transmission in a particulate medium; and laser generation of shock waves in droplets. (LSP)

  4. Deep space mission integration with the space transportation system. [Galileo mission using Space Transportation System

    NASA Technical Reports Server (NTRS)

    Gray, W. B.

    1979-01-01

    The Galileo mission is the first interplanetary mission scheduled to use the Space Transportation System (STS). Therefore, Galileo is the trailblazer for mission integration of a deep space mission with the STS. A short overview of the Galileo mission is presented as background for the discussion of the mission integration effort. The components of the STS and the mission integration system are defined, documentation requirements explained, the work of the Flight Design Working Group described, and several examples of the types of problems dealt with are given. The steps of mission integration are shown from introducing requirements into the system to resolving conflicts that arise between the payload project and the STS operator. Conclusions are drawn from the Galileo mission integration effort to aid future payload projects in working with the STS.

  5. The Sodium-Dependent Inorganic Phosphate Transporter SLC34A1 (NaPi-IIa) Is Not Localized in the Mouse Brain

    PubMed Central

    Larsson, Max; Morland, Cecilie; Poblete-Naredo, Irais; Biber, Jürg; Danbolt, Niels Christian; Gundersen, Vidar

    2011-01-01

    The sodium-dependent inorganic phosphate transporter NaPi-IIa is expressed in the kidney. Here, the authors used a polyclonal antiserum raised against NaPi-IIa- and NaPi-IIa-deficient mice to characterize its expression in nervous tissue. Western blots showed that a NaPi-IIa immunoreactive band (~90 kDa) was only present in wild-type kidney membranes and not in kidney knockout or wild-type brain membranes. In the water-soluble fraction of wild-type and knockout brains, another band (~50 kDa) was observed; this band was not detected in the kidney. Light and electron microscopic immunohistochemistry using the NaPi-IIa antibodies showed immunolabeling of kidney tubules in wild-type but not knockout mice. In the brain, labeling of presynaptic nerve terminals was present also in NaPi-IIa-deficient mice. This labeling pattern was also produced by the NaPi-IIa preimmune serum. The authors conclude that the polyclonal antiserum is specific toward NaPi-IIa in the kidney, but in the brain, immunolabeling is caused by a cross-reaction of the antiserum with an unknown cytosolic protein that is not present in the kidney. This tissue-specific cross-reactivity highlights a potential pitfall when validating antibody specificity using knockout mouse-derived tissue other than the specific tissue of interest and underlines the utility of specificity testing using preimmune sera. PMID:21606201

  6. Coregulated expression of the Na+/phosphate Pho89 transporter and Ena1 Na+-ATPase allows their functional coupling under high-pH stress.

    PubMed

    Serra-Cardona, Albert; Petrezsélyová, Silvia; Canadell, David; Ramos, José; Ariño, Joaquín

    2014-12-01

    The yeast Saccharomyces cerevisiae has two main high-affinity inorganic phosphate (Pi) transporters, Pho84 and Pho89, that are functionally relevant at acidic/neutral pH and alkaline pH, respectively. Upon Pi starvation, PHO84 and PHO89 are induced by the activation of the PHO regulon by the binding of the Pho4 transcription factor to specific promoter sequences. We show that PHO89 and PHO84 are induced by alkalinization of the medium with different kinetics and that the network controlling Pho89 expression in response to alkaline pH differs from that of other members of the PHO regulon. In addition to Pho4, the PHO89 promoter is regulated by the transcriptional activator Crz1 through the calcium-activated phosphatase calcineurin, and it is under the control of several repressors (Mig2, Nrg1, and Nrg2) coordinately regulated by the Snf1 protein kinase and the Rim101 transcription factor. This network mimics the one regulating expression of the Na(+)-ATPase gene ENA1, encoding a major determinant for Na(+) detoxification. Our data highlight a scenario in which the activities of Pho89 and Ena1 are functionally coordinated to sustain growth in an alkaline environment. PMID:25266663

  7. Sphingosine-1-Phosphate Rapidly Increases Cortisol Biosynthesis and the Expression of Genes Involved in Cholesterol Uptake and Transport in H295R Adrenocortical Cells

    PubMed Central

    Lucki, Natasha C.; Li, Donghui; Sewer, Marion B.

    2011-01-01

    In the acute phase of adrenocortical steroidogenesis, adrenocorticotrophin (ACTH) activates a cAMP/PKA-signaling pathway that promotes the transport of free cholesterol to the inner mitochondrial membrane. We have previously shown that ACTH rapidly stimulates the metabolism of sphingolipids and the secretion of sphingosine-1-phosphate (S1P) in H295R cells. In this study, we examined the effect of S1P on genes involved in the acute phase of steroidogenesis. We show that S1P increases the expression of steroidogenic acute regulatory protein (StAR), 18-kDa translocator protein (TSPO), low-density lipoprotein receptor (LDLR), and scavenger receptor class B type I (SR-BI). S1P-induced StAR mRNA expression requires Gαi signaling, phospholipase C (PLC), Ca2+/calmodulin-dependent kinase II (CamKII), and ERK1/2 activation. S1P also increases intracellular Ca2+, the phosphorylation of hormone sensitive lipase (HSL) at Ser563, and cortisol secretion. Collectively, these findings identify multiple roles for S1P in the regulation of glucocorticoid biosynthesis. PMID:21864647

  8. The H+-ATPase HA1 of Medicago truncatula Is Essential for Phosphate Transport and Plant Growth during Arbuscular Mycorrhizal Symbiosis.

    PubMed

    Krajinski, Franziska; Courty, Pierre-Emmanuel; Sieh, Daniela; Franken, Philipp; Zhang, Haoqiang; Bucher, Marcel; Gerlach, Nina; Kryvoruchko, Igor; Zoeller, Daniela; Udvardi, Michael; Hause, Bettina

    2014-04-29

    A key feature of arbuscular mycorrhizal symbiosis is improved phosphorus nutrition of the host plant via the mycorrhizal pathway, i.e., the fungal uptake of Pi from the soil and its release from arbuscules within root cells. Efficient transport of Pi from the fungus to plant cells is thought to require a proton gradient across the periarbuscular membrane (PAM) that separates fungal arbuscules from the host cell cytoplasm. Previous studies showed that the H(+)-ATPase gene HA1 is expressed specifically in arbuscule-containing root cells of Medicago truncatula. We isolated a ha1-2 mutant of M. truncatula and found it to be impaired in the development of arbuscules but not in root colonization by Rhizophagus irregularis hyphae. Artificial microRNA silencing of HA1 recapitulated this phenotype, resulting in small and truncated arbuscules. Unlike the wild type, the ha1-2 mutant failed to show a positive growth response to mycorrhizal colonization under Pi-limiting conditions. Uptake experiments confirmed that ha1-2 mutants are unable to take up phosphate via the mycorrhizal pathway. Increased pH in the apoplast of abnormal arbuscule-containing cells of the ha1-2 mutant compared with the wild type suggests that HA1 is crucial for building a proton gradient across the PAM and therefore is indispensible for the transfer of Pi from the fungus to the plant. PMID:24781114

  9. Disruption of the Phosphate Transporter Pit1 in Hepatocytes Improves Glucose Metabolism and Insulin Signaling by Modulating the USP7/IRS1 Interaction.

    PubMed

    Forand, Anne; Koumakis, Eugénie; Rousseau, Alice; Sassier, Yohann; Journe, Clément; Merlin, Jean-François; Leroy, Christine; Boitez, Valérie; Codogno, Patrice; Friedlander, Gérard; Cohen, Isabelle

    2016-09-01

    The liver plays a central role in whole-body lipid and glucose homeostasis. Increasing dietary fat intake results in increased hepatic fat deposition, which is associated with a risk for development of insulin resistance and type 2 diabetes. In this study, we demonstrate a role for the phosphate inorganic transporter 1 (PiT1/SLC20A1) in regulating metabolism. Specific knockout of Pit1 in hepatocytes significantly improved glucose tolerance and insulin sensitivity, enhanced insulin signaling, and decreased hepatic lipogenesis. We identified USP7 as a PiT1 binding partner and demonstrated that Pit1 deletion inhibited USP7/IRS1 dissociation upon insulin stimulation. This prevented IRS1 ubiquitination and its subsequent proteasomal degradation. As a consequence, delayed insulin negative feedback loop and sustained insulin signaling were observed. Moreover, PiT1-deficient mice were protected against high-fat-diet-induced obesity and diabetes. Our findings indicate that PiT1 has potential as a therapeutic target in the context of metabolic syndrome, obesity, and diabetes. PMID:27568561

  10. Transporters, channels, or simple diffusion? Dogmas, atypical roles and complexity in transport systems.

    PubMed

    Conde, Artur; Diallinas, George; Chaumont, François; Chaves, Manuela; Gerós, Hernâni

    2010-06-01

    The recent breakthrough discoveries of transport systems assigned with atypical functions provide evidence for complexity in membrane transport biochemistry. Some channels are far from being simple pores creating hydrophilic passages for solutes and can, unexpectedly, act as enzymes, or mediate high-affinity uptake, and some transporters are surprisingly able to function as sensors, channels or even enzymes. Furthermore, numerous transport studies have demonstrated complex multiphasic uptake kinetics for organic and mineral nutrients. The biphasic kinetics of glucose uptake in Saccharomyces cerevisiae, a result of several genetically distinct uptake systems operating simultaneously, is a classical example that is a subject of continuous debate. In contrast, some transporters display biphasic kinetics, being bona fidae dual-affinity transporters, their kinetic properties often modulated by post-translational regulation. Also, aquaporins have recently been reported to exhibit diverse transport properties and can behave as highly adapted, multifunctional channels, transporting solutes such as CO(2), hydrogen peroxide, urea, ammonia, glycerol, polyols, carbamides, purines and pyrimidines, metalloids, glycine, and lactic acid, rather than being simple water pores. The present review provides an overview on some atypical functions displayed by transporter proteins and discusses how this novel knowledge on cellular uptake systems may be related to complex multiphasic uptake kinetics often seen in a wide variety of living organisms and the intriguing diffusive uptake of sugars and other solutes. PMID:20026419

  11. Nanostructured silicate substituted calcium phosphate (NanoSiCaPs) nanoparticles - Efficient calcium phosphate based non-viral gene delivery systems.

    PubMed

    Shekhar, Sudhanshu; Roy, Abhijit; Hong, Daeho; Kumta, Prashant N

    2016-12-01

    Nanostructured ceramic particles, particularly, nanoparticles of calcium phosphate (CaP) remain an attractive option among the various types of non-viral gene delivery vectors studied because of their safety, biocompatibility, biodegradability, and ease of handling as well as their adsorptive capacity for DNA. We have accordingly developed an enhanced version of nanostructured calcium phosphates (NanoCaPs), by substituting known amounts of silicate for phosphate in the hydroxyapatite (HA) lattice (NanoSiCaPs). Results indicate that in addition to the excellent transfection levels exhibited by un-substituted NanoCaPs alone in vitro, an additional 20-50% increase in transfection is observed for NanoCaPs containing 8.3-50mol% silicate aptly called NanoSiCaPs, owing to its rapid dissolution properties enabling nanoparticles escaping the lysosomal degradation. However, high silicate substitution (>50mol%) resulted in a drastic decline in transfection as the synthesized NanoCaPs deviated far from the characteristic hydroxyapatite phase formed as evidenced by the materials characterization results. PMID:27612739

  12. 25. VIEW FOURTH FLOOR, ELEVATOR PULLEY TRANSPORT SYSTEM, LOOKING AT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    25. VIEW FOURTH FLOOR, ELEVATOR PULLEY TRANSPORT SYSTEM, LOOKING AT TOP MAIN WOOD AND STEEL BEAM SUPPORT SYSTEM, NORTHWEST - Bates Manufacturing Company, Storehouse, Northeast corner of Chestnut Street & Hines Alley, Lewiston, Androscoggin County, ME

  13. Information Transport Systems at IBM's Corporate Technical Institutes.

    ERIC Educational Resources Information Center

    Grubb, Ralph E.; Pryzdial, Edward F.

    1986-01-01

    Describes the facilities and major networks of IBM's Corporate Technical Institute state-of-the-art residential campus at Thornwood, New York. Explains the operations and components of its information transport system and the capabilities of its cabling system. (ML)

  14. Activation of a new proline transport system in Salmonella typhimurium.

    PubMed

    Ekena, K; Liao, M K; Maloy, S

    1990-06-01

    Proline uptake can be mediated by three different transport systems in wild-type Salmonella typhimurium: a high-affinity proline transport system encoded by the putP gene and two glycine-betaine transport systems with a low affinity for proline encoded by the proP and proU genes. However, only the PutP permease transports proline well enough t allow growth on proline as a sole carbon or nitrogen source. By selecting for mutations that allow a putP mutant to grow on proline as a sole nitrogen source, we isolated mutants (designated proZ) that appeared to activate a cryptic proline transport system. These mutants enhanced the transport of proline and proline analogs but did not require the function of any of the known proline transport genes. The mutations mapped between 75 and 77.5 min on the S. typhimurium linkage map. Proline transport by the proZ mutants was competitively inhibited by isoleucine and leucine, which suggests that the ProZ phenotype may be due to unusual mutations that alter the substrate specificity of the branched-chain amino acid transport system encoded by the liv genes. PMID:2160931

  15. Ferric oxide quantum dots in stable phosphate glass system and their magneto-optical study

    SciTech Connect

    Garaje, Sunil N.; Apte, Sanjay K.; Kumar, Ganpathy; Panmand, Rajendra P.; Naik, Sonali D.; Mahajan, Satish M.; Chand, Ramesh; Kale, Bharat B.

    2013-02-15

    Graphical abstract: We report synthesis of ferric oxide embedded low melting phosphate glass nanocomposite and also the effect of ferric oxide nanoparticles (NCs) content on the optical and magneto-optical properties of the glasses. Faraday rotation of the glass nanocomposites was measured and showed variation in Verdet constant with concentration of ferric oxide. Interestingly, the host glass itself showed fairly good Verdet constant (11.5°/T cm) and there is a threefold enhancement in the Verdet constant of ferric oxide quantum dot-glass nanocomposite. Highlights: ► We synthesize ferric oxide embedded low melting stable phosphate glass nanocomposite. ► Glasses doped with 0.25 and 2% ferric oxide show particle size in the range of 4–12 nm. ► The host phosphate glass itself shows fairly good Verdet constant (11.5°/T cm). ► Glasses doped with 0.25% ferric oxide show high Verdet constant (30.525°/T cm). ► The as synthesis glasses may have potential application in magneto optical devices. -- Abstract: Herein, we report the synthesis of ferric oxide embedded low melting phosphate glass nanocomposite and also the effect of ferric oxide nanoparticles content on the optical and magneto-optical properties of the glasses. The optical study clearly showed red shift in optical cut off with increasing ferric oxide concentration. The band gap of the host glass was observed to be 3.48 eV and it shifted to 3.14 eV after doping with ferric oxide. The glasses doped with 0.25 and 2% ferric oxide showed particle size of 4–6 nm and 8–12 nm, respectively. Faraday rotation of the glass nanocomposites was measured and showed variation in the Verdet constant as per increasing concentration of ferric oxide. Interestingly, the host glass itself showed fairly good Verdet constant (11.5°/T cm) and threefold enhancement was observed in the Verdet constant of ferric oxide quantum dot-glass nanocomposite.

  16. Cryogenic Transport of High-Pressure-System Recharge Gas

    NASA Technical Reports Server (NTRS)

    Ungar, Eugene K,; Ruemmele, Warren P.; Bohannon, Carl

    2010-01-01

    A method of relatively safe, compact, efficient recharging of a high-pressure room-temperature gas supply has been proposed. In this method, the gas would be liquefied at the source for transport as a cryogenic fluid at or slightly above atmospheric pressure. Upon reaching the destination, a simple heating/expansion process would be used to (1) convert the transported cryogenic fluid to the room-temperature, high-pressure gaseous form in which it is intended to be utilized and (2) transfer the resulting gas to the storage tank of the system to be recharged. In conventional practice for recharging high-pressure-gas systems, gases are transported at room temperature in high-pressure tanks. For recharging a given system to a specified pressure, a transport tank must contain the recharge gas at a much higher pressure. At the destination, the transport tank is connected to the system storage tank to be recharged, and the pressures in the transport tank and the system storage tank are allowed to equalize. One major disadvantage of the conventional approach is that the high transport pressure poses a hazard. Another disadvantage is the waste of a significant amount of recharge gas. Because the transport tank is disconnected from the system storage tank when it is at the specified system recharge pressure, the transport tank still contains a significant amount of recharge gas (typically on the order of half of the amount transported) that cannot be used. In the proposed method, the cryogenic fluid would be transported in a suitably thermally insulated tank that would be capable of withstanding the recharge pressure of the destination tank. The tank would be equipped with quick-disconnect fluid-transfer fittings and with a low-power electric heater (which would not be used during transport). In preparation for transport, a relief valve would be attached via one of the quick-disconnect fittings (see figure). During transport, the interior of the tank would be kept at a near

  17. Transport processes in biological systems: Tumoral cells and human brain

    NASA Astrophysics Data System (ADS)

    Lucia, Umberto

    2014-01-01

    The entropy generation approach has been developed for the analysis of complex systems, with particular regards to biological systems, in order to evaluate their stationary states. The entropy generation is related to the transport processes related to exergy flows. Moreover, cancer can be described as an open complex dynamic and self-organizing system. Consequently, it is used as an example useful to evaluate the different thermo-chemical quantities of the transport processes in normal and in tumoral cells systems.

  18. Healthy F-16 pilots show no evidence of exposure to tri-ortho-cresyl phosphate through the on-board oxygen generating system.

    PubMed

    Tacal, Ozden; Schopfer, Lawrence M

    2014-05-25

    About 18% of fighter pilots complain of ill symptoms that begin during flight and persist for days. A possible source of toxicity is the air supplied through the on board oxygen generating system. The air passes through the jet engine before it is enriched for oxygen and breathed through an oxygen mask. While in the jet engine, the air can become contaminated with jet engine lubricating oil. A potentially toxic component in jet engine oil is tri-ortho-cresyl phosphate (TOCP), which is metabolically activated to the highly reactive cresyl saligenin phosphate. The cresyl saligenin phosphate reacts with butyrylcholinesterase (BChE) to make a covalent adduct on serine 198. The purpose of this work was to determine whether the blood of healthy, active-duty F-16 pilots has measurable levels of the cresyl phosphate adduct. BChE was immunopurified from 0.5ml plasma by binding to immobilized monoclonal mAb2. BChE protein was released with acetic acid, digested with pepsin and analyzed by LC-MS/MS on the 5600 Triple TOF mass spectrometer. Positive controls for quantifying the limit of detection were plasma samples containing known amounts of cresyl saligenin phosphate treated plasma. The cresyl phosphate adduct eluted at 31.3min with an observed parent ion mass of 966.4m/z and characteristic daughter ions 778.3, 673.3, and 602.3m/z. Control experiments demonstrated that as little as 0.1% of the 1-2μg BChE recovered from 0.5ml plasma could be detected as the cresyl phosphate adduct on peptide FGES198AGAAS. Mass spectrometry analysis of plasma from fifteen healthy F-16 pilots showed that none had evidence of exposure to TOCP. It was concluded that the on-board oxygen generating system, when operating properly, did not deliver tri-ortho-cresyl phosphate in the oxygen supply. PMID:24661946

  19. Chapter 9: Model Systems for Formation and Dissolution of Calcium Phosphate Minerals

    SciTech Connect

    Orme, C A; Giocondi, J L

    2006-07-29

    Calcium phosphates are the mineral component of bones and teeth. As such there is great interest in understanding the physical mechanisms that underlie their growth, dissolution, and phase stability. Control is often achieved at the cellular level by the manipulation of solution states and the use of crystal growth modulators such as peptides or other organic molecules. This chapter begins with a discussion of solution speciation in body fluids and relates this to important crystal growth parameters such as the supersaturation, pH, ionic strength and the ratio of calcium to phosphate activities. We then discuss the use of scanning probe microscopy as a tool to measure surface kinetics of mineral surfaces evolving in simplified solutions. The two primary themes that we will touch on are the use of microenvironments that temporally evolve the solution state to control growth and dissolution; and the use of various growth modifiers that interact with the solution species or with mineral surfaces to shift growth away from the lowest energy facetted forms. The study of synthetic minerals in simplified solution lays the foundation for understand mineralization process in more complex environments found in the body.

  20. Procurement of a fully licensed radioisotope thermoelectric generator transportation system

    SciTech Connect

    Adkins, H.E.; Bearden, T.E.

    1990-10-01

    A fully licensed transportation system for Radioisotope Thermoelectric Generators and Light-Weight Radioisotope Heater Units is currently being designed and built. The system will comply with all applicable US Department of Transportation regulations without the use of a DOE Alternative.'' The US Department of Transportation has special double containment'' requirements for plutonium. The system packaging uses a doubly contained bell jar'' concept. A refrigerated trailer is used for cooling the high-heat payloads. The same packaging is used for both high- and low-heat payloads. The system is scheduled to be available for use by mid-1992. 4 refs., 4 figs., 2 tabs.

  1. Human behavior research and the design of sustainable transport systems

    NASA Astrophysics Data System (ADS)

    Schauer, James J.

    2011-09-01

    Transport currently represents approximately 19% of the global energy demand and accounts for about 23% of the global carbon dioxide emissions (IEA 2009). As the demand for mobility is expected to continue to increase in the coming decades, the stabilization of atmospheric carbon dioxide levels will require the evolution of transport, along with power generation, building design and manufacturing. The continued development of these sectors will need to include changes in energy sources, energy delivery, materials, infrastructure and human behavior. Pathways to reducing carbon from the transport sector have unique challenges and opportunities that are inherent to the human choices and behavioral patterns that mold the transportation systems and the associated energy needs. Technology, government investment, and regulatory policies have a significant impact on the formulation of transportation infrastructure; however, the role of human behavior and public acceptance on the efficiency and effectiveness of transport systems should not be underestimated. Although developed, rapidly developing, and underdeveloped nations face different challenges in the establishment of transport infrastructure that can meet transport needs while achieving sustainable carbon dioxide emissions, the constraints that establish the domain of possibilities are closely related for all nations. These constraints include capital investment, fuel supplies, power systems, and human behavior. Throughout the world, there are considerable efforts directed at advancing and optimizing the financing of sustainable infrastructures, the production of low carbon fuels, and the production of advanced power systems, but the foundational work on methods to understand human preferences and behavior within the context of transport and the valuation of reductions in carbon dioxide emissions is greatly lagging behind. These methods and the associated understanding of human behavior and the willingness to pay for

  2. Control of machine functions or transport systems

    SciTech Connect

    Woodley, M.D.; Lee, M.J.; Jaeger, J.; King, A.S.

    1983-01-01

    A computer code, COMFORT, has been developed at SLAC for on-line calculation of the strengths of magnetic elements in an electron storage ring or transport beam line, subject to first order fitting constraints on the ring or beam line parameters. This code can also be used off-line as an interactive lattice or beam line design tool.

  3. Membrane Transporters and Folate Homeostasis; Intestinal Absorption, Transport into Systemic Compartments and Tissues

    PubMed Central

    Zhao, Rongbao; Matherly, Larry H.; Goldman, I. David

    2013-01-01

    Folates, the generic term for the family of B vitamins, are derived entirely from dietary sources, and are key one-carbon donors required for de novo nucleotide and methionine synthesis. These highly hydrophilic molecules utilize genetically distinct and functionally diverse transport systems to enter cells: the reduced folate carrier (RFC), the proton-coupled folate transporter (PCFT), and the folate receptors. Each plays a unique role in mediating folate transport across epithelia and into systemic tissues. With the recent discovery of the mechanism of intestinal folate absorption, and the clarification of the genetic basis for the autosomal recessive disorder, hereditary folate malabsorption, involving loss-of-function mutations in PCFT protein, it is now possible to piece together how these folate transporters contribute, both individually and collectively, to folate homeostasis in humans. This review focuses on the physiological roles of these major folate transporters with a brief consideration of their impact on the pharmacological activities of antifolates. PMID:19173758

  4. A 10-Gbps optical WiMAX transport system.

    PubMed

    Lin, Ying-Pyng; Lu, Hai-Han; Wu, Po-Yi; Chen, Chia-Yi; Jhang, Tai-Wei; Ruan, Sheng-Siang; Wu, Kuan-Hung

    2014-02-10

    A 10-Gbps optical worldwide interoperability for microwave access (WiMAX) transport system employing vertical cavity surface emitting laser (VCSEL) and spatial light modulator (SLM) with 16-quadrature amplitude modulation (QAM)-orthogonal frequency-division multiplexing (OFDM) modulating signal is proposed. With the assistance of equalizer and low noise amplifier (LNA) at the receiving site, good bit error rate (BER) performance, clear constellation map, and clear eye diagram are achieved in the proposed systems. An optical WiMAX transport system, transmitting 16-QAM-OFDM signal over a 6-m free-space link, with a data rate of 10 Gbps is successfully demonstrated. Such a 10-Gbps optical WiMAX transport system would be attractive for providing services including Internet and telecommunication services. Our proposed system is suitable for the free-space lightwave transport system in visible light communication (VLC) application. PMID:24663567

  5. Nuclear reactor heat transport system component low friction support system

    DOEpatents

    Wade, Elman E.

    1980-01-01

    A support column for a heavy component of a liquid metal fast breeder reactor heat transport system which will deflect when the pipes leading coolant to and from the heavy component expand or contract due to temperature changes includes a vertically disposed pipe, the pipe being connected to the heavy component by two longitudinally spaced cycloidal dovetail joints wherein the distal end of each of the dovetails constitutes a part of the surface of a large diameter cylinder and the centerlines of these large diameter cylinders intersect at right angles and the pipe being supported through two longitudinally spaced cycloidal dovetail joints wherein the distal end of each of the dovetails constitutes a part of the surface of a large diameter cylinder and the centerlines of these large diameter cylinders intersect at right angles, each of the cylindrical surfaces bearing on a flat and horizontal surface.

  6. Conceptual Design of a Mars Surface Transportation System (MSTS)

    NASA Astrophysics Data System (ADS)

    Collins, Chad; Gomez, Alex; Muniz, Rick; Musson, Dave

    1999-01-01

    We have proposed a design for a Mars Surface Transportation System. The design will support multi-range and multi-purpose scientific/exploratory activities for extended periods. Several assumptions were made before developing a desiun: 1. This system is to be deployed early in a series of piloted landings on the planet surface. 2. A Mars surface base has already been established. 3. A transport system to and from Mars already exists. 4. The capacity to transport this proposed system exists within the current transport design. 5. Facilities exist at this base for the supply of fuel and other consumables. 6. Medical facilities are a component of the main base. 7. The surface conditions of Mars are known and are.accurate. It was decided that the transportation system design should support a crew of two for up to four weeks away from the primary base. In order to support multiple mission requirements, the system is modular and m multi-configurable, The main structural aspects of the design are: 1. An inflatable habitat module. 2. Independently powered and remotely controllable wheel trucks to allow multiple configurations and ease of system assembly. 3. Parabolic space trusses for hi-h structural stability with low overall system mass. In addition to these design aspects, new and existing concepts for control systems, power, radiation protection, and crew safety have been incorporated into the transportation system design.

  7. Peptidoglycan metabolism is controlled by the WalRK (YycFG) and PhoPR two-component systems in phosphate-limited Bacillus subtilis cells.

    PubMed

    Bisicchia, Paola; Lioliou, Efthimia; Noone, David; Salzberg, Letal I; Botella, Eric; Hübner, Sebastian; Devine, Kevin M

    2010-02-01

    In Bacillus subtilis, the WalRK (YycFG) two-component system controls peptidoglycan metabolism in exponentially growing cells while PhoPR controls the response to phosphate limitation. Here we examine the roles of WalRK and PhoPR in peptidoglycan metabolism in phosphate-limited cells. We show that B. subtilis cells remain viable in a phosphate-limited state for an extended period and resume growth rapidly upon phosphate addition, even in the absence of a PhoPR-mediated response. Peptidoglycan synthesis occurs in phosphate-limited wild-type cells at approximately 27% the rate of exponentially growing cells, and at approximately 18% the rate of exponentially growing cells in the absence of PhoPR. In phosphate-limited cells, the WalRK regulon genes yocH, cwlO(yvcE), lytE and ydjM are expressed in a manner that is dependent on the WalR recognition sequence and deleting these genes individually reduces the rate of peptidoglycan synthesis. We show that ydjM expression can be activated by PhoP approximately P in vitro and that PhoP occupies its promoter in phosphate-limited cells. However, iseA(yoeB) expression cannot be repressed by PhoP approximately P in vitro, but can be repressed by non-phosphorylated WalR in vitro. Therefore, we conclude that peptidoglycan metabolism is controlled by both WalRK and PhoPR in phosphate-limited B. subtilis cells. PMID:20487291

  8. Electrical Power Systems for NASA's Space Transportation Program

    NASA Technical Reports Server (NTRS)

    Lollar, Louis F.; Maus, Louis C.

    1998-01-01

    Marshall Space Flight Center (MSFC) is the National Aeronautics and Space Administration's (NASA) lead center for space transportation systems development. These systems include earth to orbit launch vehicles, as well as vehicles for orbital transfer and deep space missions. The tasks for these systems include research, technology maturation, design, development, and integration of space transportation and propulsion systems. One of the key elements in any transportation system is the electrical power system (EPS). Every transportation system has to have some form of electrical power and the EPS for each of these systems tends to be as varied and unique as the missions they are supporting. The Preliminary Design Office (PD) at MSFC is tasked to perform feasibility analyses and preliminary design studies for new projects, particularly in the space transportation systems area. All major subsystems, including electrical power, are included in each of these studies. Three example systems being evaluated in PD at this time are the Liquid Fly Back Booster (LFBB) system, the Human Mission to Mars (HMM) study, and a tether based flight experiment called the Propulsive Small Expendable Deployer System (ProSEDS). These three systems are in various stages of definition in the study phase.

  9. Natural hazard impacts on transport systems: analyzing the data base of transport accidents in Russia

    NASA Astrophysics Data System (ADS)

    Petrova, Elena

    2015-04-01

    We consider a transport accident as any accident that occurs during transportation of people and goods. It comprises of accidents involving air, road, rail, water, and pipeline transport. With over 1.2 million people killed each year, road accidents are one of the world's leading causes of death; another 20-50 million people are injured each year on the world's roads while walking, cycling, or driving. Transport accidents of other types including air, rail, and water transport accidents are not as numerous as road crashes, but the relative risk of each accident is much higher because of the higher number of people killed and injured per accident. Pipeline ruptures cause large damages to the environment. That is why safety and security are of primary concern for any transport system. The transport system of the Russian Federation (RF) is one of the most extensive in the world. It includes 1,283,000 km of public roads, more than 600,000 km of airlines, more than 200,000 km of gas, oil, and product pipelines, 115,000 km of inland waterways, and 87,000 km of railways. The transport system, especially the transport infrastructure of the country is exposed to impacts of various natural hazards and weather extremes such as heavy rains, snowfalls, snowdrifts, floods, earthquakes, volcanic eruptions, landslides, snow avalanches, debris flows, rock falls, fog or icing roads, and other natural factors that additionally trigger many accidents. In June 2014, the Ministry of Transport of the RF has compiled a new version of the Transport Strategy of the RF up to 2030. Among of the key pillars of the Strategy are to increase the safety of the transport system and to reduce negative environmental impacts. Using the data base of technological accidents that was created by the author, the study investigates temporal variations and regional differences of the transport accidents' risk within the Russian federal regions and a contribution of natural factors to occurrences of different

  10. A low earth orbit skyhook tether transportation system

    NASA Technical Reports Server (NTRS)

    Penzo, Paul A.

    1988-01-01

    This paper discusses the design concept of a structure, called the Skyhook Tether Transportation System (STTS) which may be used to transport mass to higher or lower orbits or to capture objects from higher or lower orbits. An analysis is presented for the possibility of the STTS to perform the function of transporting masses suborbitally, capturing the objects, and then releasing them to a higher orbit, the GEO, the moon, or for an escape. It is shown that, although the possibility of such a system is limited by the tether strength, even a modest system can yield considerable benefits in propellant savings if it is used in combination with chemical propulsion.

  11. Heating and Cooling System Design for a Modern Transportable Container

    SciTech Connect

    Berger, Jason E.

    2015-06-01

    Sandia National Laboratories (SNL) has been tasked with the design of a modern transportable container (MTC) for use in high reliability transportation environments. The container is required to transport cargo capable of generating its own heat and operate under the United States’ climatic extremes. In response to these requirements, active heating and cooling is necessary to maintain a controlled environment inside the container. The following thesis project documents the design of an active heating, active cooling, and combined active heating and cooling system (now referred to as active heating and cooling systems) through computational thermal analyses, scoping of commercial system options, and mechanical integration with the container’s structure.

  12. Nucleocytoplasmic transport of ribosomes in a eukaryotic system: Is there a facilitated transport process

    SciTech Connect

    Khanna-Gupta, A.; Ware, V.C. )

    1989-03-01

    The authors have examined the kinetics of the process by which ribosomes are exported from the nucleus to the cytoplasm using Xenopus laevis oocytes microinjected into the germinal vesicle with radiolabeled ribosomes or ribosomal subunits from X. laevis, Tetrahymena thermophila, or Escherichia coli. Microinjected eukaryotic mature ribosomes are redistributed into the oocyte cytoplasm by an apparent carrier-mediated transport process that exhibits saturation kinetics as increasing amounts of ribosomes are injected. T. thermophila ribosomes are competent to traverse the Xenopus nuclear envelope, suggesting that the basic mechanism underlying ribosome transport is evolutionarily conserved. Microinjected E. coli ribosomes are not transported in this system, indicating that prokaryotic ribosomes lack the signals required for transport. Surprisingly, coinjected small (40S) and large (60S) subunits from T. thermophila are transported significantly faster than individual subunits. These observations support a facilitated transport model for the translocation of ribosomal subunits as separate units across the nuclear envelope whereby the transport rate of 60S or 40S subunits is enhanced by the presence of the partner subunit. Although the basic features of the transport mechanism have been preserved through evolution, other aspects of the process may be mediated through species-specific interactions. They hypothesize that a species-specific nuclear 40S-60S subunit association may expedite the transport of individual subunits across the nuclear envelope.

  13. A Numbering System for MFS Transporter Proteins

    PubMed Central

    Lee, Joanna; Sands, Zara A.; Biggin, Philip C.

    2016-01-01

    The Major Facilitator Superfamily (MFS) is one of the largest classes of secondary active transporters and is widely expressed in many domains of life. It is characterized by a common 12-transmembrane helix motif that allows the selective transport of a vast range of diverse substrates across the membrane. MFS transporters play a central role in many physiological processes and are increasingly recognized as potential drug targets. Despite intensive efforts, there are still only a handful of crystal structures and therefore homology modeling is likely to be a necessary process for providing models to interpret experiments for many years to come. However, the diversity of sequences and the multiple conformational states these proteins can exist in makes the process significantly more complicated, especially for sequences for which there is very little sequence identity to known templates. Inspired by the approach adopted many years ago for GPCRs, we have analyzed the large number of MFS sequences now available alongside the current structural information to propose a series of conserved contact points that can provide additional guidance for the homology modeling process. To enable cross-comparison across MFS models we also present a numbering scheme that can be used to provide a point of reference within each of the 12 transmembrane regions. PMID:27314000

  14. Conceptual design of an RTG Facility Transportation System

    NASA Astrophysics Data System (ADS)

    Black, Stephen J.; Gentzlinger, Robert C.; Lujan, Richard E.

    1994-06-01

    The conceptual design of an Radioisotope Thermoelectric Generator (RTG) Facility Transportation System which is part of the overall RTG Transportation System has been completed and is described in detail. The Facility Transportation System serves to provide locomotion, cooling, shock protection and data acquisition for the RTG package during loading and unloading sequences. The RTG Facility Transportation System consists of a Transporter Subsystem, a Package Cooling Subsystem, and a Shock Limiting Transit Device Subsystem. The Transporter Subsystem is a uniquely designed welded steel cart combined with a pneumatically-driven hand tug for locomotion. The Package Cooling Subsystem provides five kilowatts of active liquid cooling via an on-board refrigeration system. The Shock limiting Transit Device Subsystem consists of a consumable honeycomb transit frame which provides shock protection for the 3855 kg (8500 LB) RTG package. These subsystems have been combined into an integrated system which will facilitate the unloading and loading of the RTG, of the Transport Trailer as well as meet ALARA radiation Package into and out exposure guidelines.

  15. Conceptual design of an RTG Facility Transportation System

    SciTech Connect

    Black, S.J.; Gentzlinger, R.C.; Lujan, R.E.

    1994-06-03

    The conceptual design of an Radioisotope Thermoelectric Generator (RTG) Facility Transportation System which is part of the overall RTG Transportation System has been completed and is described in detail. The Facility Transportation System serves to provide locomotion, cooling, shock protection and data acquisition for the RTG package during loading and unloading sequences. The RTG Facility Transportation System consists of a Transporter Subsystem, a Package Cooling Subsystem, and a Shock Limiting Transit Device Subsystem. The Transporter Subsystem is a uniquely designed welded steel cart combined with a pneumatically-driven hand tug for locomotion. The Package Cooling Subsystem provides five kilowatts of active liquid cooling via an on-board refrigeration system. The Shock limiting Transit Device Subsystem consists of a consumable honeycomb transit frame which provides shock protection for the 3855 kg (8500 LB) RTG package. These subsystems have been combined into an integrated system which will facilitate the unloading and loading of the RTG , of the Transport Trailer as well as meet ALARA radiation Package into and out exposure guidelines.

  16. GROUNDWATER MASS TRANSPORT AND EQUILIBRIUM CHEMISTRY MODEL FOR MULTICOMPONENT SYSTEMS

    EPA Science Inventory

    A mass transport model, TRANQL, for a multicomponent solution system has been developed. The equilibrium interaction chemistry is posed independently of the mass transport equations which leads to a set of algebraic equations for the chemistry coupled to a set of differential equ...

  17. Systems evaluation of low density air transportation concepts

    NASA Technical Reports Server (NTRS)

    Bruce, R. W.; Webb, H. M.

    1972-01-01

    Methods were studied for improving air transportation to low-density population regions in the U.S. through the application of new aeronautical technology. The low-density air service concepts are developed for selected regions, and critical technologies that presently limit the effective application of low-density air transportation systems are identified.

  18. Phase formation and evolution in the silicon substituted tricalcium phosphate/apatite system.

    PubMed

    Reid, J W; Pietak, A; Sayer, M; Dunfield, D; Smith, T J N

    2005-06-01

    The sintering of silicon doped calcium phosphate ceramics prepared from a basic colloidal hydroxyapatite (Ca5(PO4)3OH or HA) precipitate mixed with silica over 800 degrees C yields a phase mixture of tricalcium phosphate phases (TCP) designated Si-TCP, beta-TCP and a silicon substituted dehydrated apatite (Si-Ap). The Si-TCP phase is defined as a combination of a silicon stabilized TCP in which the silicon content attains a saturated value (Ca3(P0.9Si0.1O3.95)2 or Si-TCP(sat)) and alpha-TCP (Ca3(PO4)2). Si-TCP(sat) has the same crystalline space group (P2(1)/a) as alpha-TCP, but with characteristically different lattice parameters due to the substitution of silicon in tetrahedral phosphorus sites. The nucleation and growth kinetics of Si-TCP in samples of composition 0.2 mol SiO2:mol HA (0.2:1) and 1 mol SiO2:mol HA (1:1) can be understood in terms of the initial growth of alpha-TCP at a silica-HA interface followed by a transformation to Si-TCP(sat) or beta-TCP. A thermodynamic model for the formation of Si-TCP(sat) predicts a nucleation temperature of 795 degrees C, in close agreement with experiment. If sufficient silicon is available, the alpha-TCP transforms to Si-TCP(sat) during extended sintering. In the absence of sufficient silicon, the alpha-TCP transforms to beta-TCP. PMID:15603784

  19. pH-responsive drug delivery system based on AIE luminogen functionalized layered zirconium phosphate nano-platelets

    SciTech Connect

    Li, Dongdong Zhang, Yuping; Zhou, Bingbing

    2015-05-15

    Aggregation-induced emission (AIE) luminogen, quaternary tetraphenylethene cation (TPEN), was successfully incorporated into layered α-zirconium phosphate (α-ZrP) by using co-precipitation method to form inorganic–organic hybrid materials. The obtained materials show the characteristic hexagonal platelet shape with the interlayer distance did not reveal significant difference compared with pure α-ZrP. In addition, the obtained hybrid materials emit strong blue emission centered at 476 nm in aqueous media due to the electrostatic interactions of TPEN with the anionic framework of α-ZrP, which largely restrict their intramolecular rotation. More importantly, the materials provide a pH dependent release of doxorubicin (DOX), suggesting that AIE luminogen functionalized α-ZrP may be used as an imaging guided and pH-responsive delivery system for targeting therapy. - Graphical abstract: AIE luminogen was successfully incorporated into layered α-zirconium phosphate by a co-precipitation method to form inorganic–organic hybrid materials, showing a pH dependent release of DOX. - Highlights: • AIE luminogen cation was incorporated into layered α-ZrP by co-precipitation method. • The obtained material emits strong blue emission upon UV irradiation. • The material exhibits pH dependent release of DOX. • The AIE functionalized α-ZrP has potential applications in imaging guided therapy.

  20. Biopolymer-induced calcium phosphate scaling in membrane-based water treatment systems: Langmuir model films studies.

    PubMed

    Dahdal, Yara N; Oren, Yoram; Schwahn, Dietmar; Pipich, Vitaliy; Herzberg, Moshe; Ying, Wang; Kasher, Roni; Rapaport, Hanna

    2016-07-01

    Biofouling and scaling on reverse osmosis (RO) or nanofiltration (NF) membranes during desalination of secondary and tertiary effluents pose an obstacle that limits the reuse of wastewater. In this study we explored the mineral scaling induced by biopolymers originated from bacterial biofilms: bovine serum albumin (BSA), fibrinogen, lysozyme and alginic acid, as well as an extracts of extracellular polymeric substances (EPS) from bio-fouled RO membranes from wastewater treatment facility. Mineralization studies were performed on Langmuir films of the biopolymers deposited at the interface of a solution simulating RO desalination of secondary-treated wastewater effluents. All studied biopolymers and EPS induced heterogeneous mineralization of mainly calcium phosphate. Using IR spectroscopy coupled with systematic quantitative analysis of the surface pressure versus molecular-area isotherms, we determined the mineralization tendencies of the biopolymers to be in the order of: fibrinogen>lysozyme>BSA>alginic acid. The biopolymers and EPS studied here were found to be accelerators of calcium-phosphate mineralization. This study demonstrates the utilization of Langmuir surface-pressure area isotherms and a model solution in quantitatively assessing the mineralization tendencies of various molecular components of EPS in context of membrane-based water treatment systems. PMID:27015648

  1. Economic analysis of new space transportation systems: Executive summary

    NASA Technical Reports Server (NTRS)

    1971-01-01

    An economic analysis of alternative space transportation systems is presented. Results indicate that the expendable systems represent modest investments, but the recurring costs of operation would remain high. The space shuttle and tug system requires a substantial investment, but would substantially reduce the recurring costs of operation. Economic benefits and costs of the different systems are also analyzed. Findings are summarized.

  2. Features of the acid protease partition in aqueous two-phase systems of polyethylene glycol-phosphate: chymosin and pepsin.

    PubMed

    Spelzini, Darío; Farruggia, Beatriz; Picó, Guillermo

    2005-07-01

    The partitioning of chymosin (from Aspergilus niger) and pepsin (from bovine stomach) was carried out in aqueous-two phase systems formed by polyethyleneglycol-potassium phosphate. The effects of polymer concentration, molecular mass and temperature were analysed. The partition was assayed at pH 7.0 in systems of polyethyleneglycol of molecular mass: 1450, 3350, 6000 and 8000. Both proteins showed high affinity for the polyethyleneglycol rich phase. The increase of polyethyleneglycol concentration favoured the protein transfer to the top phase, suggesting an important protein-polymer interaction. Polyethyleneglycol proved to have a stabilizing effect on the chymosin and pepsin, increasing its protein secondary structure. This finding agreed with the enhancement of the milk clotting activity by the polyethyleneglycol. The method appears to be suitable as a first step for the purification of these proteins from their natural sources. PMID:15894519

  3. The Involvement of OsPHO1;1 in the Regulation of Iron Transport Through Integration of Phosphate and Zinc Deficiency Signaling.

    PubMed

    Saenchai, Chorpet; Bouain, Nadia; Kisko, Mushtak; Prom-U-Thai, Chanakan; Doumas, Patrick; Rouached, Hatem

    2016-01-01

    Plants survival depends on their ability to cope with multiple nutrient stresses that often occur simultaneously, such as the limited availability of essential elements inorganic phosphate (Pi), zinc (Zn), and iron (Fe). Previous research has provided information on the genes involved in efforts by plants to maintain homeostasis when a single nutrient (Pi, Zn, or Fe) is depleted. Recent findings on nutritional stress suggest that plant growth capacity is influenced by a complex tripartite interaction between Pi, Zn, and Fe homeostasis. However, despite its importance, how plants integrate multiple nutritional stimuli into complex developmental programs, and which genes are involved in this tripartite (Pi ZnFe) interaction is still not clear. The aim of this study was to examine the physiological and molecular responses of rice (Oriza sativa L.) to a combination of Pi, Zn, and/or Fe deficiency stress conditions. Results showed that Fe deficiency had the most drastic single-nutrient effect on biomass, while the Zn deficiency-effect depended on the presence of Pi in the medium. Interestingly, the observed negative effect of Fe starvation was alleviated by concomitant Pi or PiZn depletion. Members of the OsPHO1 family showed a differential transcriptional regulation in response PiZnFe combinatory stress conditions. Particularly, the transcripts of the OsPHO1;1 sense and its natural antisense cis-NatPHO1;1 showed the highest accumulation under PiZn deficiency. In this condition, the Ospho1;1 mutants showed over-accumulation of Fe in roots compared to wild type plants. These data reveal coordination between pathways involved in Fe transport and PiZn signaling in rice which involves the OsPHO1; 1, and support the hypothesis of a genetic basis for Pi, Zn, and Fe signaling interactions in plants. PMID:27092147

  4. The Involvement of OsPHO1;1 in the Regulation of Iron Transport Through Integration of Phosphate and Zinc Deficiency Signaling

    PubMed Central

    Saenchai, Chorpet; Bouain, Nadia; Kisko, Mushtak; Prom-u-thai, Chanakan; Doumas, Patrick; Rouached, Hatem

    2016-01-01

    Plants survival depends on their ability to cope with multiple nutrient stresses that often occur simultaneously, such as the limited availability of essential elements inorganic phosphate (Pi), zinc (Zn), and iron (Fe). Previous research has provided information on the genes involved in efforts by plants to maintain homeostasis when a single nutrient (Pi, Zn, or Fe) is depleted. Recent findings on nutritional stress suggest that plant growth capacity is influenced by a complex tripartite interaction between Pi, Zn, and Fe homeostasis. However, despite its importance, how plants integrate multiple nutritional stimuli into complex developmental programs, and which genes are involved in this tripartite (Pi ZnFe) interaction is still not clear. The aim of this study was to examine the physiological and molecular responses of rice (Oriza sativa L.) to a combination of Pi, Zn, and/or Fe deficiency stress conditions. Results showed that Fe deficiency had the most drastic single-nutrient effect on biomass, while the Zn deficiency-effect depended on the presence of Pi in the medium. Interestingly, the observed negative effect of Fe starvation was alleviated by concomitant Pi or PiZn depletion. Members of the OsPHO1 family showed a differential transcriptional regulation in response PiZnFe combinatory stress conditions. Particularly, the transcripts of the OsPHO1;1 sense and its natural antisense cis-NatPHO1;1 showed the highest accumulation under PiZn deficiency. In this condition, the Ospho1;1 mutants showed over-accumulation of Fe in roots compared to wild type plants. These data reveal coordination between pathways involved in Fe transport and PiZn signaling in rice which involves the OsPHO1; 1, and support the hypothesis of a genetic basis for Pi, Zn, and Fe signaling interactions in plants. PMID:27092147

  5. Study of aircraft in intraurban transportation systems. Volume 4: Appendix

    NASA Technical Reports Server (NTRS)

    Stout, E. G.; Kesling, P. H.; Matteson, H. C.; Sherwood, D. E.; Tuck, W. R., Jr.; Vaughn, L. A.

    1971-01-01

    An appendix of the supporting data leading to conclusions and recommendations for an effective intraurban transportation system from volumes 1, 2, and 3 is presented. The data are given in tables and graphs.

  6. Space transportation system payload status and reimbursement policy

    NASA Technical Reports Server (NTRS)

    Yardley, J. F.

    1977-01-01

    The status of the Space Transportation System (STS) is reviewed. The management structure and project planning status are discussed, including considerations of STS utilization, payloads, cost assessments, and pricing policy.

  7. Transportation System After Next & Comments on AvSTAR Planning

    NASA Technical Reports Server (NTRS)

    Pearce, Robert

    2001-01-01

    The purpose of this presentation is to define and identify: the role of transportation in supporting future US needs, trends, system after next, supporting research and education, priority investments, and barriers.

  8. 20-Gbps optical LiFi transport system.

    PubMed

    Ying, Cheng-Ling; Lu, Hai-Han; Li, Chung-Yi; Cheng, Chun-Jen; Peng, Peng-Chun; Ho, Wen-Jeng

    2015-07-15

    A 20-Gbps optical light-based WiFi (LiFi) transport system employing vertical-cavity surface-emitting laser (VCSEL) and external light injection technique with 16-quadrature amplitude modulation (QAM)-orthogonal frequency-division multiplexing (OFDM) modulating signal is proposed. Good bit error rate (BER) performance and clear constellation map are achieved in our proposed optical LiFi transport systems. An optical LiFi transport system, delivering 16-QAM-OFDM signal over a 6-m free-space link, with a data rate of 20 Gbps, is successfully demonstrated. Such a 20-Gbps optical LiFi transport system provides the advantage of a free-space communication link for high data rates, which can accelerate the visible laser light communication (VLLC) deployment. PMID:26176448

  9. World Energy Projection System Plus Model Documentation: Transportation Model

    EIA Publications

    2011-01-01

    This report documents the objectives, analytical approach and development of the World Energy Projection System Plus (WEPS ) International Transportation model. It also catalogues and describes critical assumptions, computational methodology, parameter estimation techniques, and model source code.

  10. Los Alamos radiation transport code system on desktop computing platforms

    SciTech Connect

    Briesmeister, J.F.; Brinkley, F.W.; Clark, B.A.; West, J.T. )

    1990-01-01

    The Los Alamos Radiation Transport Code System (LARTCS) consists of state-of-the-art Monte Carlo and discrete ordinates transport codes and data libraries. These codes were originally developed many years ago and have undergone continual improvement. With a large initial effort and continued vigilance, the codes are easily portable from one type of hardware to another. The performance of scientific work-stations (SWS) has evolved to the point that such platforms can be used routinely to perform sophisticated radiation transport calculations. As the personal computer (PC) performance approaches that of the SWS, the hardware options for desk-top radiation transport calculations expands considerably. The current status of the radiation transport codes within the LARTCS is described: MCNP, SABRINA, LAHET, ONEDANT, TWODANT, TWOHEX, and ONELD. Specifically, the authors discuss hardware systems on which the codes run and present code performance comparisons for various machines.

  11. MRS (monitored retrievable storage) to transportation system interfaces

    SciTech Connect

    Row, T.H.; Croff, A.G.

    1987-01-01

    In March 1987, the US Department of Energy presented to Congress the proposal to construct and operate a facility for the monitored retrievable storage (MRS) of spent fuel at a site on the Clinch River in the Roane County portions of Oak Ridge. In discussing the MRS to Transportation System Interfaces, the authors provide a blending of the technical and institutional issues, for they do not believe the solutions to success of this enterprise lie wholly in one area. The authors cover: early chronology of the MRS; comparison of total-system life cycle cost estimates of the authorized system and improved-performance system (i.e., the system that includes a facility for MRS); transportation costs resulting from shipping, security and cask; assumptions for dedicated rail transport from MRS to repository; and significant results from the Total System Life Cycle Cost (TSLCC) analysis of the improved performance system. (AT)

  12. Further evidence for a two-step model of glucose-transport regulation. Inositol phosphate-oligosaccharides regulate glucose-carrier activity.

    PubMed Central

    Obermaier-Kusser, B; Mühlbacher, C; Mushack, J; Seffer, E; Ermel, B; Machicao, F; Schmidt, F; Häring, H U

    1989-01-01

    The insulin effect on glucose uptake is not sufficiently explained by a simple glucose-carrier translocation model. Recent studies rather suggest a two-step model of carrier translocation and carrier activation. We used several pharmacological tools to characterize the proposed model further. We found that inositol phosphate (IP)-oligosaccharides isolated from the drug Actovegin, as well as the alkaloid vinblastine, show a partial insulin-like effect on glucose-transport activity of fat-cells (3-O-methylglucose uptake, expressed as % of equilibrium value per 4 s: basal 5.8%, insulin 59%, IP-oligosaccharides 30%, vinblastine 29%) without inducing carrier translocation. On the other hand, two newly developed anti-diabetic compounds (alpha-activated carbonic acids, BM 130795 and BM 13907) induced carrier translocation to the same extent as insulin and phorbol esters [cytochalasin-B-binding sites in plasma membranes: basal 5 pmol/mg of protein, insulin 13 pmol/mg of protein, TPA (12-O-tetradecanoylphorbol 13-acetate) 11.8 pmol/mg of protein, BM 130795 10.8 pmol/mg of protein], but produce also only 40-50% of the insulin effect on glucose-transport activity (basal 5.8%, insulin 59%, TPA 23%, BM 130795 35%). Almost the full insulin effect was mimicked by a combination of phorbol esters and IP-oligosaccharides (basal 7%, insulin 50%, IP-oligosaccharides 30%, TPA 23%, IP-oligosaccharides + TPA 45%). None of these substances stimulated insulin-receptor kinase in vitro or in vivo, suggesting a post-kinase site of action. The data confirm the following aspects of the proposed model: (1) carrier translocation and carrier activation are two independently regulated processes; (2) the full insulin effect is mimicked only by a simultaneous stimulation of carrier translocation and intrinsic carrier activity, suggesting that insulin acts through a synergism of both mechanisms; (3) IP-oligosaccharides might be involved in the transmission of a stimulatory signal on carrier activity

  13. Future Air Transportation System Breakout Series Report

    NASA Technical Reports Server (NTRS)

    2001-01-01

    This presentation discusses: AvSTAR Future System Effort Critically important; Investment in the future; Need to follow a systems engineering process; and Efforts need to be worked in worldwide context

  14. Fold assisted transport in graphene systems

    NASA Astrophysics Data System (ADS)

    Carrillo-Bastos, Ramon; Faria, Daiara; Jiang, Yuhang; Mao, Jinhai; Li, Guohong; Andrei, Eva Y.; Latge, Andrea; Sandler, Nancy

    Sasaki pointed out that a constant uniaxial strain applied along the zigzag direction in graphene causes localized states, akin to edge states in nanoribbons. These states are dispersionless and can carry ballistic transport. Recent experiments reported the presence of ballistic channels in graphene grown on SiC characterized with STM spectroscopy. In this work, we show that out-of plane deformations in the form of folds produce states as those predicted by Sasaki. Using tight-binding calculations and recursive Green's function methods, we obtain conductance, density of states (DOS), local density of states, and band structure (BS) for graphene nanoribbons with zigzag termination. Regions with enhanced DOS are identified in the deformed area corresponding to states in new flattened bands in the BS and new ballistic channels in the conductance. Adjusting the fold parameters, desired properties of these states can be tailored. Our results show that folds could serve as pathways for electronic transport and open the possibility of circuitry design within a simple graphene membrane. Support: DOE-FG02-99ER45742, NSF-DMR 1207108 and 1508325.

  15. Cost competitive space transportation system for geostationary payloads

    NASA Technical Reports Server (NTRS)

    Jones, C. R.

    1976-01-01

    A geostationary satellite system designer will have a number of launch vehicles to consider in the system designs for the 1980s. The Space transportation System (the shuttle orbiter plus upper stage) offers the opportunity for lower system cost in comparison with the expendable launch vehicles. An analysis of a spin stabilized solid rocket motor stage has demonstrated the feasibility of this upper stage concept. A cost competitive Space Transportation System (STS) for geostationary payloads is made possible by achievement of the STS cost goals, multiple launch from the STS orbiter, and a user-provided spin stabilized upper stage.

  16. Flow and transport in hierarchically fractured systems

    SciTech Connect

    Karasaki, K.

    1993-01-01

    Preliminary results indicate that flow in the saturated zone at Yucca Mountain is controlled by fractures. A current conceptual model assumes that the flow in the fracture system can be approximately by a three-dimensionally interconnected network of linear conduits. The overall flow system of rocks at Yucca Mountain is considered to consist of hierarchically structured heterogeneous fracture systems of multiple scales. A case study suggests that it is more appropriate to use the flow parameters of the large fracture system for predicting the first arrival time, rather than using the bulk average parameters of the total system.

  17. Flow and transport in hierarchically fractured systems

    SciTech Connect

    Karasaki, K.

    1993-12-31

    Preliminary results indicate that flow in the saturated zone at Yucca Mountain is controlled by fractures. A current conceptual model assumes that the flow in the fracture system can be approximated by a three-dimensionally interconnected network of linear conduits. The overall flow system of rocks at Yucca Mountain is considered to consist of hierarchically structured heterogeneous fracture systems of multiple scales. A case study suggests that it is more appropriate to use the flow parameters of the large fracture system for predicting the first arrival time, rather than using the bulk average parameters of the total system.

  18. A Pollen Protein, NaPCCP, That Binds Pistil Arabinogalactan Proteins Also Binds Phosphatidylinositol 3-Phosphate and Associates with the Pollen Tube Endomembrane System1[C][W][OA

    PubMed Central

    Lee, Christopher B.; Kim, Sunran; McClure, Bruce

    2009-01-01

    As pollen tubes grow toward the ovary, they are in constant contact with the pistil extracellular matrix (ECM). ECM components are taken up during growth, and some pistil molecules exert their effect inside the pollen tube. For instance, the Nicotiana alata 120-kD glycoprotein (120K) is an abundant arabinogalactan protein that is taken up from the ECM; it has been detected in association with pollen tube vacuoles, but the transport pathway between these compartments is unknown. We recently identified a pollen C2 domain-containing protein (NaPCCP) that binds to the carboxyl-terminal domain of 120K. As C2 domain proteins mediate protein-lipid interactions, NaPCCP could function in intracellular transport of 120K in pollen tubes. Here, we describe binding studies showing that the NaPCCP C2 domain is functional and that binding is specific for phosphatidylinositol 3-phosphate. Subcellular fractionation, immunolocalization, and live imaging results show that NaPCCP is associated with the plasma membrane and internal pollen tube vesicles. Colocalization between an NaPCCP∷green fluorescent protein fusion and internalized FM4-64 suggest an association with the endosomal system. NaPCCP localization is altered in pollen tubes rejected by the self-incompatibility mechanism, but our hypothesis is that it has a general function in the transport of endocytic cargo rather than a specific function in self-incompatibility. NaPCCP represents a bifunctional protein with both phosphatidylinositol 3-phosphate- and arabinogalactan protein-binding domains. Therefore, it could function in the transport of pistil ECM proteins in the pollen tube endomembrane system. PMID:19098095

  19. Workshop on technology issues of superconducting Maglev transportation systems

    SciTech Connect

    Wegrzyn, J.E. ); Shaw, D.T. )

    1991-09-27

    There exists a critical need in the United States to improve its ground transportation system. One suggested system that offers many advantages over the current transportation infrastructure is Maglev. Maglev represents the latest evolution in very high and speed ground transportation, where vehicles are magnetically levitated, guided, and propelled over elevated guideways at speeds of 300 miles per hour. Maglev is not a new concept but is, however, receiving renewed interest. The objective of this workshop was to further promote these interest by bringing together a small group of specialists in Maglev technology to discuss Maglev research needs and to identify key research issues to the development of a successful Maglev system. The workshop was organized into four sessions based on the following technical areas: Materials, Testing, and Shielding; Magnet Design and Cryogenic Systems; Propulsion and Levitation Systems; and, System Control and Integration.

  20. Security plan for the Automated Transportation Management System

    SciTech Connect

    Not Available

    1994-04-01

    The Automated Transportation Management System (ATMS) is an unclassified non-sensitive system consisting of hardware and software designed to facilitate the shipment of goods for the US Department of Energy (DOE). The system is secured against waste, fraud, abuse, misuse, and programming errors through a series of security measures that are discussed in detail in this document.

  1. Fabrication of catalyzed ion transport membrane systems

    DOEpatents

    Carolan, Michael Francis; Kibby, Charles Leonard

    2013-06-04

    Process for fabricating a catalyzed ion transport membrane (ITM). In one embodiment, an uncatalyzed ITM is (a) contacted with a non-reducing gaseous stream while heating to a temperature and for a time period sufficient to provide an ITM possessing anion mobility; (b) contacted with a reducing gaseous stream for a time period sufficient to provide an ITM having anion mobility and essentially constant oxygen stoichiometry; (c) cooled while contacting the ITM with the reducing gaseous stream to provide an ITM having essentially constant oxygen stoichiometry and no anion mobility; and (d) treated by applying catalyst to at least one of (1) a porous mixed conducting multicomponent metallic oxide (MCMO) layer contiguous with a first side of a dense layer of MCMO and (2) a second side of the dense MCMO layer. In another embodiment, these steps are carried out in the alternative order of (a), (d), (b), and (c).

  2. Arrow 227: Air transport system design simulation

    NASA Technical Reports Server (NTRS)

    Bontempi, Michael; Bose, Dave; Brophy, Georgeann; Cashin, Timothy; Kanarios, Michael; Ryan, Steve; Peterson, Timothy

    1992-01-01

    The Arrow 227 is a student-designed commercial transport for use in a overnight package delivery network. The major goal of the concept was to provide the delivery service with the greatest potential return on investment. The design objectives of the Arrow 227 were based on three parameters; production cost, payload weight, and aerodynamic efficiency. Low production cost helps to reduce initial investment. Increased payload weight allows for a decrease in flight cycles and, therefore, less fuel consumption than an aircraft carrying less payload weight and requiring more flight cycles. In addition, fewer flight cycles will allow a fleet to last longer. Finally, increased aerodynamic efficiency in the form of high L/D will decrease fuel consumption.

  3. pH-responsive drug delivery system based on AIE luminogen functionalized layered zirconium phosphate nano-platelets

    NASA Astrophysics Data System (ADS)

    Li, Dongdong; Zhang, Yuping; Zhou, Bingbing

    2015-05-01

    Aggregation-induced emission (AIE) luminogen, quaternary tetraphenylethene cation (TPEN), was successfully incorporated into layered α-zirconium phosphate (α-ZrP) by using co-precipitation method to form inorganic-organic hybrid materials. The obtained materials show the characteristic hexagonal platelet shape with the interlayer distance did not reveal significant difference compared with pure α-ZrP. In addition, the obtained hybrid materials emit strong blue emission centered at 476 nm in aqueous media due to the electrostatic interactions of TPEN with the anionic framework of α-ZrP, which largely restrict their intramolecular rotation. More importantly, the materials provide a pH dependent release of doxorubicin (DOX), suggesting that AIE luminogen functionalized α-ZrP may be used as an imaging guided and pH-responsive delivery system for targeting therapy.

  4. Systemic delivery of siRNA by hyaluronan-functionalized calcium phosphate nanoparticles for tumor-targeted therapy

    NASA Astrophysics Data System (ADS)

    Qiu, Chong; Wei, Wei; Sun, Jing; Zhang, Hai-Tao; Ding, Jing-Song; Wang, Jian-Cheng; Zhang, Qiang

    2016-06-01

    In this study, hyaluronan (HA)-functionalized calcium phosphate nanoparticles (CaP-AHA/siRNA NPs) were developed for an injectable and targetable delivery of siRNA, which were prepared by coating the alendronate-hyaluronan graft polymer (AHA) around the surface of calcium phosphate-siRNA co-precipitates. The prepared CaP-AHA/siRNA NPs had a uniform spherical core-shell morphology with an approximate size of 170 nm and zeta potential of -12 mV. The coating of hydrophilic HA improved the physical stability of nanoparticles over one month due to the strong interactions between phosphonate and calcium. In vitro experiments demonstrated that the negatively charged CaP-AHA/siRNA NPs could effectively deliver EGFR-targeted siRNA into A549 cells through CD44-mediated endocytosis and significantly down-regulate the level of EGFR expression. Also, the internalized CaP-AHA/siRNA NPs exhibited a pH-responsive release of siRNA, indicating that the acidification of lysosomes probably facilitated the disassembling of nanoparticles and the resultant ions sharply increased the inner osmotic pressure and thus expedited the release of siRNA from late lysosomes into the cytoplasm. Furthermore, in vivo tumor therapy demonstrated that high accumulation of CaP-AHA/siEGFR NPs in tumor led to a significant tumor growth inhibition with a specific EGFR gene silencing effect after intravenous administration in nude mice xenografted with A549 tumor, along with a negligible body weight loss. These results suggested that the CaP-AHA/siRNA NPs could be an effective and safe systemic siRNA delivery system for a RNAi-based tumor targeted therapy strategy.In this study, hyaluronan (HA)-functionalized calcium phosphate nanoparticles (CaP-AHA/siRNA NPs) were developed for an injectable and targetable delivery of siRNA, which were prepared by coating the alendronate-hyaluronan graft polymer (AHA) around the surface of calcium phosphate-siRNA co-precipitates. The prepared CaP-AHA/siRNA NPs had a uniform

  5. Silver phosphate/graphitic carbon nitride as an efficient photocatalytic tandem system for oxygen evolution.

    PubMed

    Yang, Xiaofei; Tang, Hua; Xu, Jingsan; Antonietti, Markus; Shalom, Menny

    2015-04-24

    Herein, we show the facile synthesis of an efficient silver phosphate/graphitic carbon nitride (Ag3 PO4 /g-C3 N4 ) photocatalyst for oxygen production and pollutant degradation by using electrostatically driven assembly and ion-exchange processes. The composite materials demonstrate a sheet-like C3 N4 structure, decorated with different Ag3 PO4 particles sizes. Detailed analysis of the reactions mechanism by electron-spin resonance and radical-capture agents strongly imply the formation of an in situ Z-scheme by the evolution of small silver nanoparticles in the interface of the materials under illumination. The Ag nanoparticles improve charge separation within the composite material by acting as a storage and recombination center for electrons and holes from Ag3 PO4 and C3 N4 , respectively. In addition, the photostability of Ag3 PO4 is enhanced relative to that of the bulk materials, which results in a stabilized heterojunction. We believe that this work provides new insight into the operation mechanism of composite photocatalysts for water splitting and opens the possibility for advanced photocatalysis based on the higher oxidation power of Ag3 PO4 . PMID:25693743

  6. Biomembranes from slaughterhouse blood erythrocytes as prolonged release systems for dexamethasone sodium phosphate.

    PubMed

    Drvenica, Ivana T; Bukara, Katarina M; Ilić, Vesna Lj; Mišić, Danijela M; Vasić, Borislav Z; Gajić, Radoš B; Đorđević, Verica B; Veljović, Đorđe N; Belić, Aleksandar; Bugarski, Branko M

    2016-07-01

    The present study investigated preparation of bovine and porcine erythrocyte membranes from slaughterhouse blood as bio-derived materials for delivery of dexamethasone-sodium phosphate (DexP). The obtained biomembranes, i.e., ghosts were characterized in vitro in terms of morphological properties, loading parameters, and release behavior. For the last two, an UHPLC/-HESI-MS/MS based analytical procedure for absolute drug identification and quantification was developed. The results revealed that loading of DexP into both type of ghosts was directly proportional to the increase of drug concentration in the incubation medium, while incubation at 37°C had statistically significant effect on loaded amount of DexP (P < 0.05). The encapsulation efficiency was about fivefold higher in porcine compared to bovine ghosts. Insight into ghosts' surface morphology by field emission-scanning electron microscopy and atomic force microscopy confirmed that besides inevitable effects of osmosis, DexP inclusion itself had no observable additional effect on the morphology of the ghosts carriers. DexP release profiles were dependent on erythrocyte ghost type and amount of residual hemoglobin. However, sustained DexP release was achieved and shown over 3 days from porcine ghosts and 5 days from bovine erythrocyte ghosts. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:1046-1055, 2016. PMID:27254304

  7. Injectable nanoamorphous calcium phosphate based in situ gel systems for the treatment of periapical lesions.

    PubMed

    Mostafa, Amany A; Zaazou, Mohamed H; Chow, Laurence C; Mahmoud, Azza A; Zaki, Dalia Y; Basha, Mona; Abdel Hamid, Mohamed A; Khallaf, Maram E; Sharaf, Nehal F; Hamdy, Tamer M

    2015-12-01

    Nonsurgical local treatment of a periapical lesion arising from trauma or bacterial infection is a promising innovative approach. The present study investigated the feasibility of developing injectable amorphous calcium phosphate nanoparticles (ACP NPs) and ACP NPs loaded with an anti-inflammatory drug; ibuprofen (IBU-ACP NPs) in the form of thermoreversible in situ gels to treat periapical lesions with the stimulation of bone formation. NPs were produced by a spray-drying technique. Different formulations of Poloxamer 407 were incorporated with/without the produced NPs to form injectable gels. A drug release study was carried out. A 3 month in vivo test on a dog model also was assessed. Results showed successful incorporation of the drug into the NPs of CP during spray drying. The particles had mean diameters varying from 100 to 200 nm with a narrow distribution. A drug release study demonstrated controlled IBU release from IBU-ACP NPs at a pH of 7.4 over 24 h. The gelation temperature of the injectable in situ gels based on Poloxamer 407 was measured to be 30 °C. After 3 months of implantation in dogs, the results clearly demonstrated that the inclusion of ACP NPs loaded with IBU showed high degrees of periapical bone healing and cementum layer deposition around the apical root tip. PMID:26541174

  8. Advanced Vehicle system concepts. [nonpetroleum passenger transportation

    NASA Technical Reports Server (NTRS)

    Hardy, K. S.; Langendoen, J. M.

    1983-01-01

    Various nonpetroleum vehicle system concepts for passenger vehicles in the 1990's are being considered as part of the Advanced Vehicle (AV) Assessment at the Jet Propulsion Laboratory. The vehicle system and subsystem performance requirements, the projected characteristics of mature subsystem candidates, and promising systems are presented. The system candidates include electric and hybrid vehicles powered by electricity with or without a nonpetroleum power source. The subsystem candidates include batteries (aqueous-mobile, flow, high-temperature, and metal-air), fuel cells (phosphoric acid, advanced acids, and solid polymer electrolyte), nonpetroleum heat engines, advanced dc and ac propulsion components, power-peaking devices, and transmissions.

  9. Transport Information System using Query Centric Cyber Physical Systems (QCPS)

    NASA Astrophysics Data System (ADS)

    Mundra, Ankit; Rathee, Geetanjali; Chawla, Meenu; Soni, Ashutosh

    2014-01-01

    To incorporate the computation and communication with the physical world, next generation architecture i.e. CPS is viewed as a new technology. To improve the better interaction with the physical world or to perk up the electricity delivery usage, various CPS based approaches have been introduced. Recently several GPS equipped smart phones and sensor based frameworks have been proposed which provide various services i.e. environment estimation, road safety improvement but encounter certain limitations like elevated energy consumption and high computation cost. To meet the high reliability and safety requirements, this paper introduces a novel approach based on QCPS model which provides several users services (discussed in this paper). Further, this paper proposed a Transport Information System (TIS), which provide the communication with lower cost overhead by arranging the similar sensors in the form of grids. Each grid has a coordinator which interacts with cloud to process the user query. In order to evaluate the performance of proposed approach we have implemented a test bed of 16 wireless sensor nodes and have shown the performance in terms of computation and communication cost.

  10. Systemic delivery of siRNA by hyaluronan-functionalized calcium phosphate nanoparticles for tumor-targeted therapy.

    PubMed

    Qiu, Chong; Wei, Wei; Sun, Jing; Zhang, Hai-Tao; Ding, Jing-Song; Wang, Jian-Cheng; Zhang, Qiang

    2016-07-14

    In this study, hyaluronan (HA)-functionalized calcium phosphate nanoparticles (CaP-AHA/siRNA NPs) were developed for an injectable and targetable delivery of siRNA, which were prepared by coating the alendronate-hyaluronan graft polymer (AHA) around the surface of calcium phosphate-siRNA co-precipitates. The prepared CaP-AHA/siRNA NPs had a uniform spherical core-shell morphology with an approximate size of 170 nm and zeta potential of -12 mV. The coating of hydrophilic HA improved the physical stability of nanoparticles over one month due to the strong interactions between phosphonate and calcium. In vitro experiments demonstrated that the negatively charged CaP-AHA/siRNA NPs could effectively deliver EGFR-targeted siRNA into A549 cells through CD44-mediated endocytosis and significantly down-regulate the level of EGFR expression. Also, the internalized CaP-AHA/siRNA NPs exhibited a pH-responsive release of siRNA, indicating that the acidification of lysosomes probably facilitated the disassembling of nanoparticles and the resultant ions sharply increased the inner osmotic pressure and thus expedited the release of siRNA from late lysosomes into the cytoplasm. Furthermore, in vivo tumor therapy demonstrated that high accumulation of CaP-AHA/siEGFR NPs in tumor led to a significant tumor growth inhibition with a specific EGFR gene silencing effect after intravenous administration in nude mice xenografted with A549 tumor, along with a negligible body weight loss. These results suggested that the CaP-AHA/siRNA NPs could be an effective and safe systemic siRNA delivery system for a RNAi-based tumor targeted therapy strategy. PMID:27314204

  11. Bis(monoacylglycero)phosphate accumulation in macrophages induces intracellular cholesterol redistribution, attenuates liver-X receptor/ATP-Binding cassette transporter A1/ATP-binding cassette transporter G1 pathway, and impairs cholesterol efflux

    PubMed Central

    Luquain-Costaz, Céline; Lefai, Etienne; Arnal-Levron, Maud; Markina, Daria; Sakaï, Shota; Euthine, Vanessa; Makino, Asami; Guichardant, Michel; Yamashita, Shizuya; Kobayashi, Toshihide; Lagarde, Michel; Moulin, Philippe; Delton-Vandenbroucke, Isabelle

    2013-01-01

    Objective Endosomal signature phospholipid bis(monoacylglycero)phosphate (BMP) has been involved in the regulation of cellular cholesterol homeostasis. Accumulation of BMP is a hallmark of lipid storage disorders and was recently reported as a noticeable feature of oxidized LDL-laden macrophages. This study was designed to delineate the consequences of macrophage BMP accumulation on intracellular cholesterol distribution, metabolism and efflux and to unravel the underlying molecular mechanisms. Methods and results We have developed an experimental design to specifically increase BMP content in RAW macrophages. Following BMP accumulation, cell cholesterol distribution was markedly altered despite no change in LDL uptake and hydrolysis, cholesterol esterification, or total cell cholesterol content. The expression of cholesterol regulated genes SREBP2 and HMGCoAR was decreased by 40%, indicative of an increase of endoplasmic reticulum associated-cholesterol. Cholesterol delivery to plasma membrane was reduced as evidenced by the 20% decrease of efflux by cyclodextrin. Functionally, BMP accumulation reduced cholesterol efflux to both apoA1 and HDL by 40%, correlated with a 40% decrease in mRNA contents of ABCA1 and ABCG1 transporters and LXR α and β. Foam cell formation induced by oxidized LDL exposure was exacerbated in BMP enriched cells. Conclusion The present work shows for the first time a strong functional link between BMP and cholesterol regulating genes involved in both intracellular metabolism and efflux. We propose that accumulation of cellular BMP might contribute to the deregulation of cholesterol homeostasis in atheromatous macrophages. PMID:23788762

  12. Manifold Coal-Slurry Transport System

    NASA Technical Reports Server (NTRS)

    Liddle, S. G.; Estus, J. M.; Lavin, M. L.

    1986-01-01

    Feeding several slurry pipes into main pipeline reduces congestion in coal mines. System based on manifold concept: feeder pipelines from each working entry joined to main pipeline that carries coal slurry out of panel and onto surface. Manifold concept makes coal-slurry haulage much simpler than existing slurry systems.

  13. Pulse thermal energy transport/storage system

    DOEpatents

    Weislogel, Mark M.

    1992-07-07

    A pulse-thermal pump having a novel fluid flow wherein heat admitted to a closed system raises the pressure in a closed evaporator chamber while another interconnected evaporator chamber remains open. This creates a large pressure differential, and at a predetermined pressure the closed evaporator is opened and the opened evaporator is closed. This difference in pressure initiates fluid flow in the system.

  14. Advanced transportation system study: Manned launch vehicle concepts for two way transportation system payloads to LEO. Program cost estimates document

    NASA Technical Reports Server (NTRS)

    Duffy, James B.

    1993-01-01

    This report describes Rockwell International's cost analysis results of manned launch vehicle concepts for two way transportation system payloads to low earth orbit during the basic and option 1 period of performance for contract NAS8-39207, advanced transportation system studies. Vehicles analyzed include the space shuttle, personnel launch system (PLS) with advanced launch system (ALS) and national launch system (NLS) boosters, foreign launch vehicles, NLS-2 derived launch vehicles, liquid rocket booster (LRB) derived launch vehicle, and cargo transfer and return vehicle (CTRV).

  15. A Configurable, Object-Oriented, Transportation System Software Framework

    SciTech Connect

    KELLY,SUZANNE M.; MYRE,JOHN W.; PRICE,MARK H.; RUSSELL,ERIC D.; SCOTT,DAN W.

    2000-08-01

    The Transportation Surety Center, 6300, has been conducting continuing research into and development of information systems for the Configurable Transportation Security and Information Management System (CTSS) project, an Object-Oriented Framework approach that uses Component-Based Software Development to facilitate rapid deployment of new systems while improving software cost containment, development reliability, compatibility, and extensibility. The direction has been to develop a Fleet Management System (FMS) framework using object-oriented technology. The goal for the current development is to provide a software and hardware environment that will demonstrate and support object-oriented development commonly in the FMS Central Command Center and Vehicle domains.

  16. Safety of high speed ground transportation systems: Safety of advanced braking concepts for high speed ground transportation systems. Final report

    SciTech Connect

    Wagner, D.P.; Ahlbeck, D.R.; Luedeke, J.F.; Cook, S.D.; Dielman, M.A.

    1995-09-01

    The objective of this study is to develop qualitative and quantitative information on the various braking strategies used in high-speed ground transportation systems in support of the Federal Railroad Administration (FRA). The approach employed in this study is composed of two steps: first, build a technical understanding of the various braking strategies, and second, perform a safety analysis for each system. The systems considered in this study include seven operating high-speed rail transportation systems and three existing magnetic levitation systems. The principal technique used in the system safety analysis is Failure Modes and Effects Analysis (FMEA), an inductive approach to identifying system failure modes that depends on a thorough understanding of the system design and operation. Key elements derived from the system safety analysis are the fault-tolerant and fail-safe characteristics of the braking systems. The report concludes with recommended guidance on the structure of potential future regulations governing high-speed rail braking systems.

  17. 78 FR 16030 - Intelligent Transportation Systems Program Advisory Committee; Notice of Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-13

    ... Intelligent Transportation Systems Program Advisory Committee; Notice of Meeting AGENCY: ITS Joint Program...: Notice. The Intelligent Transportation Systems (ITS) Program Advisory Committee (ITS PAC) will hold a... relating to the study, development, and implementation of intelligent transportation systems. Through...

  18. Fundamentals of phosphate transfer.

    PubMed

    Kirby, Anthony J; Nome, Faruk

    2015-07-21

    Historically, the chemistry of phosphate transfer-a class of reactions fundamental to the chemistry of Life-has been discussed almost exclusively in terms of the nucleophile and the leaving group. Reactivity always depends significantly on both factors; but recent results for reactions of phosphate triesters have shown that it can also depend strongly on the nature of the nonleaving or "spectator" groups. The extreme stabilities of fully ionised mono- and dialkyl phosphate esters can be seen as extensions of the same effect, with one or two triester OR groups replaced by O(-). Our chosen lead reaction is hydrolysis-phosphate transfer to water: because water is the medium in which biological chemistry takes place; because the half-life of a system in water is an accepted basic index of stability; and because the typical mechanisms of hydrolysis, with solvent H2O providing specific molecules to act as nucleophiles and as general acids or bases, are models for reactions involving better nucleophiles and stronger general species catalysts. Not least those available in enzyme active sites. Alkyl monoester dianions compete with alkyl diester monoanions for the slowest estimated rates of spontaneous hydrolysis. High stability at physiological pH is a vital factor in the biological roles of organic phosphates, but a significant limitation for experimental investigations. Almost all kinetic measurements of phosphate transfer reactions involving mono- and diesters have been followed by UV-visible spectroscopy using activated systems, conveniently compounds with good leaving groups. (A "good leaving group" OR* is electron-withdrawing, and can be displaced to generate an anion R*O(-) in water near pH 7.) Reactivities at normal temperatures of P-O-alkyl derivatives-better models for typical biological substrates-have typically had to be estimated: by extended extrapolation from linear free energy relationships, or from rate measurements at high temperatures. Calculation is free

  19. [Role of drug transporters in the central nervous system].

    PubMed

    Erdő, Franciska; Temesszentandrási-Ambrus, Csilla; Beéry, Erzsébet

    2016-03-01

    Although the presence of blood-brain barrier in the mammalian organisms was discovered in the early 1900s, its precise structure and the drug transporter proteins localized in the blood-brain barrier were identified only in the last decades. Beside the ATP-binding cassette transporter proteins responsible for the protection of the brain, the Solute Carrier transporters play also an important role in the function of the central nervous system by its feeding, energy supply and cleaning function during the metabolism. This review provides an overview on the main types of transporters located in the brain, on their localization in different cell types and the main techniques for their investigation. In the second part of this article various neurodegenerative disorders and the pathology-related transporter proteins are presented. In the light of recent experimental results new therapeutic strategies may come into the focus of research for the treatment of disorders currently without effective therapy. PMID:26920327

  20. Secondary ion collection and transport system for ion microprobe

    DOEpatents

    Ward, James W.; Schlanger, Herbert; McNulty, Jr., Hugh; Parker, Norman W.

    1985-01-01

    A secondary ion collection and transport system, for use with an ion microprobe, which is very compact and occupies only a small working distance, thereby enabling the primary ion beam to have a short focal length and high resolution. Ions sputtered from the target surface by the primary beam's impact are collected between two arcuate members having radii of curvature and applied voltages that cause only ions within a specified energy band to be collected. The collected ions are accelerated and focused in a transport section consisting of a plurality of spaced conductive members which are coaxial with and distributed along the desired ion path. Relatively high voltages are applied to alternate transport sections to produce accelerating electric fields sufficient to transport the ions through the section to an ion mass analyzer, while lower voltages are applied to the other transport sections to focus the ions and bring their velocity to a level compatible with the analyzing apparatus.

  1. A flexible micro fluid transport system featuring magnetorheological elastomer

    NASA Astrophysics Data System (ADS)

    Behrooz, Majid; Gordaninejad, Faramarz

    2016-02-01

    This study presents a flexible magnetically-actuated micro fluid transport system utilizing an isotropic magnetorheological elastomer (MRE). Theoretical modeling and analysis of this system is presented for a two-dimensional model. This fluid transport system can propel the fluid by applying a fluctuating magnetic field on the MRE. The magneto-fluid-structure interaction analysis is employed to determine movement of the solid domain and the velocity of the fluid under a controllable magnetic field. The effects of key material, geometric, and magnetic parameters on the behavior of this system are examined. It is demonstrated that the proposed system can propel the fluid unidirectionally, and the volume of the transported fluid is significantly affected by some of the design parameters.

  2. An insect gut environment reveals the induction of a new sugar-phosphate sensor system in Bacillus cereus

    PubMed Central

    Song, Fuping; Peng, Qi; Brillard, Julien; Lereclus, Didier; Nielsen-LeRoux, Christina

    2014-01-01

    Bacteria survive under various conditions by sensing stimuli triggering specific adaptive physiological responses, which are often based on membrane-integrated sensors connected to a cytoplasmic regulator. Recent studies reveal that mucus glycans may act as signal molecules for two-component systems involved in intestinal colonization. Bacillus cereus, a human and insect opportunistic pathogen was used to identify bacterial factors expressed in an insect gut infection model. The screen revealed a promoter involved in the expression of a gene with so far unknown functions. A search for gut-related compounds, inducing its transcription, identified glucose-6-phosphate as an activation signal. The gene is part of a five-gene cluster, including a two-component system. Interestingly such five gene loci are conserved in the pathogenic Bacillus group as well as in various Clostridia bacteria and are with analogy to other multi-component sensor systems in enteropathogenic bacteria, such as E. coli. Thus our results provide insights into the function of two-component and auxiliary sensor systems in host-microbe interactions and opens up possible investigations of such systems in other gut associated bacteria. PMID:24256737

  3. A silica-calcium-phosphate nanocomposite drug delivery system for the treatment of hepatocellular carcinoma: in vivo study.

    PubMed

    Swet, Jacob H; Pacheco, Hernando J; Iannitti, David A; El-Ghanam, Ahmed; McKillop, Iain H

    2014-01-01

    Hepatocellular carcinoma (HCC) is notoriously difficult to treat with systemic chemotherapy. The aim of this study was to evaluate a silica-calcium-phosphate nanocomposite (SCPC75) drug delivery system (DDS) as a means to localize cisplatin treatment within the tumor, while reducing systemic toxicity, in a rat model of HCC. The SCPC75 was prepared and loaded with cisplatin and Fourier transform infrared analyses demonstrated even drug distribution within the SCPC75. A rat model of subcutaneous HCC formation was established and animals treated by either systemic cisplatin injection (sCis) or with SCPC75-Cis hybrid placed adjacent (ADJ) to or within (IT) the tumor. Five days after implantation, 50-55% of the total cisplatin loaded had been released from the SCPC75-Cis hybrids resulting in an approximately 50% decrease in tumor volume compared with sCis treatment. sCis-treated animals exhibited severe side effects, including rapid weight loss and decreased liver and kidney function, effects not observed in SCPC75-Cis-treated animals. Analysis of cisplatin distribution demonstrated drug concentrations in the tumor were 21 and 1.5 times higher in IT and ADJ groups, respectively, compared with sCis-treated animals. These data demonstrate the SCPC75 DDS can provide an effective, localized treatment for HCC with significantly reduced toxicity when compared with systemic drug administration. PMID:23913418

  4. Modular transportable superconducting magnetic energy systems

    NASA Technical Reports Server (NTRS)

    Lieurance, Dennis; Kimball, Foster; Rix, Craig

    1995-01-01

    Design and cost studies were performed for the magnet components of mid-size (1-5 MWh), cold supported SMES systems using alternative configurations. The configurations studied included solenoid magnets, which required onsite assembly of the magnet system, and toroid and racetrack configurations which consisted of factory assembled modules. For each configuration, design concepts and cost information were developed for the major features of the magnet system including the conductor, electrical insulation, and structure. These studies showed that for mid-size systems, the costs of solenoid and toroid magnet configurations are comparable and that the specific configuration to be used for a given application should be based upon customer requirements such as limiting stray fields or minimizing risks in development or construction.

  5. Modular transportable superconducting magnetic Energy Systems

    SciTech Connect

    Lieurance, D.; Kimball, F.; Rix, C.

    1994-12-31

    Design and cost studies were performed for the magnet components of mid-size (1-5 MWh), cold supported SMES systems using alternative configurations. The configurations studied included solenoid magnets, which required onsite assembly of the magnet system, and toroid and racetrack configurations which consisted of factory assembled modules. For each configuration, design concepts and cost information were developed for the major features of the magnet system including the conductor, electrical insulation, and structure. These studies showed that for mid-size systems, the costs of solenoid and toroid magnet configurations are comparable and that the specific configuration to be used for a given application should be based upon customer requirements such as limiting stray fields or minimizing risks in development or construction.

  6. Superconducting magnet for the Maglev transport system

    NASA Astrophysics Data System (ADS)

    Nakashima, Hiroshi

    1994-07-01

    Magnetically levitated vehicles (Maglev) using superconducting magnets have been under development in Japan for the past 23 years. The superconducting magnets for the Maglev system are used in a special environment compared to other applications. They have to work stably subject to both mechanical and electromagnetic disturbances. The brief history of the Maglev development in Japan, the planning of new test line, the superconducting magnet's stability and the on-board refrigeration system will be presented.

  7. Design of a lunar transportation system

    NASA Technical Reports Server (NTRS)

    1988-01-01

    The establishment of lunar bases is the next logical step in the exploration of space. Permanent lunar bases will support scientific investigation, the industrialization of space, and the development of self-sufficiency on the Moon. Scientific investigation and research and development would lead to applications utilizing lunar material resources. By utilizing these resources, the industrialization of space can become a reality. The above two factors coupled with the development of key and enabling technologies would lead to achievement of self-sufficiency of the lunar base. Attention was focused on specific design(s) to be pursued during subsequent stages in advanced courses. Some of the objectives in the project included: (1) minimizing the transportation of construction material and fuel from earth, or maximizing the use of the lunar material; (2) use of novel materials and light weight structures; (3) use of new manufacturing methods and technology such as magnetically levitated, or superconducting materials; and (4) innovative concepts of effectively utilizing the exotic lunar conditions, i.e. high thermal gradients, lack of atmosphere, zero wind forces, and lower gravity, etc.

  8. Preliminary Transportation, Aging and Disposal Canister System Performance Specification

    SciTech Connect

    C.A Kouts

    2006-11-22

    This document provides specifications for selected system components of the Transportation, Aging and Disposal (TAD) canister-based system. A list of system specified components and ancillary components are included in Section 1.2. The TAD canister, in conjunction with specialized overpacks will accomplish a number of functions in the management and disposal of spent nuclear fuel. Some of these functions will be accomplished at purchaser sites where commercial spent nuclear fuel (CSNF) is stored, and some will be performed within the Office of Civilian Radioactive Waste Management (OCRWM) transportation and disposal system. This document contains only those requirements unique to applications within Department of Energy's (DOE's) system. DOE recognizes that TAD canisters may have to perform similar functions at purchaser sites. Requirements to meet reactor functions, such as on-site dry storage, handling, and loading for transportation, are expected to be similar to commercially available canister-based systems. This document is intended to be referenced in the license application for the Monitored Geologic Repository (MGR). As such, the requirements cited herein are needed for TAD system use in OCRWM's disposal system. This document contains specifications for the TAD canister, transportation overpack and aging overpack. The remaining components and equipment that are unique to the OCRWM system or for similar purchaser applications will be supplied by others.

  9. Transportation functions of the Civilian Radioactive Waste Management System

    SciTech Connect

    Shappert, L.B.; Attaway, C.R.; Pope, R.B. ); Best, R.E.; Danese, F.L. ); Dixon, L.D. , Martinez, GA ); Jones, R.H. , Los Gatos, CA ); Klimas, M.J. ); Peterson, R.W

    1992-03-01

    Within the framework of Public Law 97.425 and provisions specified in the Code of Federal Regulations, Title 10 Part 961, the US Department of Energy has the responsibility to accept and transport spent fuel and high-level waste from various organizations which have entered into a contract with the federal government in a manner that protects the health and safety of the public and workers. In implementing these requirements, the Office of Civilian Radioactive Waste Management (OCRWM) has, among other things, supported the identification of functions that must be performed by a transportation system (TS) that will accept the waste for transport to a federal facility for storage and/or disposal. This document, through the application of system engineering principles, identifies the functions that must be performed to transport waste under this law.

  10. Multirate Transport of Natural Tracers in a Fractured System

    NASA Astrophysics Data System (ADS)

    Kuhlman, K. L.; Malama, B.; Heath, J. E.; Gardner, P.; Robinson, D. G.

    2013-12-01

    Flow and transport in fractured systems is important in both groundwater applications and low-permeability hydrocarbon systems. We apply the multirate solute transport model to the flow of single-phase natural tracers in low-permeability hydrocarbon source rocks. We explore the effects of fracture and domain geometry, reservoir boundary conditions, and initial conditions of both the flow and transport problems using analytical and semi-analytical solutions. The flow and transport solutions will be combined to optimize reservoir characterization using a Bayesian framework. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  11. The Small Aircraft Transportation System Project: An Update

    NASA Technical Reports Server (NTRS)

    Kemmerly, Guy T.

    2006-01-01

    To all peoples in all parts of the world throughout history, the ability to move about easily is a fundamental element of freedom. The American people have charged NASA to increase their freedom and that of their children knowing that their quality of life will improve as our nation s transportation systems improve. In pursuit of this safe, reliable, and affordable personalized air transportation option, in 2000 NASA established the Small Aircraft Transportation System (SATS) Project. As the name suggests personalized air transportation would be built on smaller aircraft than those used by the airlines. Of course, smaller aircraft can operate from smaller airports and 96% of the American population is within thirty miles of a high-quality, underutilized community airport as are the vast majority of their customers, family members, and favorite vacation destinations.

  12. Rapid kinetics of liver microsomal glucose-6-phosphatase. Evidence for tight-coupling between glucose-6-phosphate transport and phosphohydrolase activity

    SciTech Connect

    Berteloot, A.; Vidal, H.; van de Werve, G. )

    1991-03-25

    Rapid kinetics of both glucose-6-P uptake and hydrolysis in fasted rat liver microsomes were investigated with a recently developed fast-sampling, rapid-filtration apparatus. Experiments were confronted with both the substrate transport and conformational models currently proposed for the glucose-6-phosphatase system. Accumulation in microsomes of 14C products from (U-14C)glucose-6-P followed biexponential kinetics. From the inside to outside product concentrations, it could be inferred that mostly glucose should accumulate inside the vesicles. While biexponential kinetics are compatible with the mathematical predictions of a simplified substrate transport model, the latter fails in explaining the burst in total glucose production over a similar time scale to that used for the uptake measurements. Since the initial rate of the burst phase in untreated microsomes exactly matched the steady-state rate of glucose production in detergent-treated vesicles, it can be definitely concluded that the substrate transport model does not describe adequately our results. While the conformational model accounts for both the burst of glucose production and the kinetics of glucose accumulation into the vesicles, it cannot explain the burst in 32Pi production from (32P)glucose-6-P measured under the same conditions. Since the amplitude of the observed bursts is not compatible with a presteady state in enzyme activity, we propose that a hysteretic transition best explains our results in both untreated and permeabilized microsomes, thus providing a new rationale to understand the molecular mechanism of the glucose-6-phosphatase system.

  13. A method for a comparison of bulk energy transport systems.

    PubMed

    Oudalov, Alexandre; Lave, Lester B; Reza, Muhamad; Bahrman, Michael P

    2009-10-15

    We model alternatives for moving bulk energy, including both private costs and accounting for environmental externalities by requiring the transport system to satisfy environment health, and safety standards. In particular, we focus on the cost and environmental trade-offs between "coal by wire," mine-mouth generation with electricity transmission, and transporting the primary energy resources with generation near the customer. Having the bulk energy transport model satisfy standards avoids the controversy associated with estimating dollar costs for constrained visibility, noise, and 50/60 Hz electromagnetic fields. A sensitivity analysis examines the implications of a range of carbon-dioxide discharge charges. PMID:19921870

  14. Study of aircraft in intraurban transportation systems, volume 3

    NASA Technical Reports Server (NTRS)

    Stout, E. G.; Kesling, P. H.; Matteson, D. E.; Sherwood, D. E.; Tuck, W. R., Jr.; Vaughn, L. A.

    1971-01-01

    An investigation of three aircraft concepts, deflected slipstream STOL, helicopter VTOL, and fixed wing STOL, is presented. An attempt was made to determine the best concept for the intraurban transportation system. Desirability of the concept was based on ease of maintenance, development timing, reliability, operating costs, and the noise produced. Indications are that the deflected slipstream STOL is best suited for intraurban transportation. Tables and graphs are included.

  15. Safety analysis report for packaging (onsite) sample pig transport system

    SciTech Connect

    MCCOY, J.C.

    1999-03-16

    This Safety Analysis Report for Packaging (SARP) provides a technical evaluation of the Sample Pig Transport System as compared to the requirements of the U.S. Department of Energy, Richland Operations Office (RL) Order 5480.1, Change 1, Chapter III. The evaluation concludes that the package is acceptable for the onsite transport of Type B, fissile excepted radioactive materials when used in accordance with this document.

  16. Conestoga 2: A low cost commercial space transport system

    NASA Technical Reports Server (NTRS)

    Rasmussen, R. O.

    1984-01-01

    Conestoga 2 is currently under development. It is capable of inserting 500 Kg satellites into 800 Km circular polar orbits. Conestoga 2 makes maximum use of existing (developed) technology and hardware. Its commercial objective is to fill a need for low cost low Earth orbital transport not efficiently served by Shuttle or larger space transport systems. Low Earth orbit markets, foreign participation, and launch site considerations are discussed along with technical and economic trade-offs.

  17. Designing a beam transport system for RHIC's electron lens

    SciTech Connect

    Gu, X.; Pikin, A.; Okamura, M.; Fischer, W.; Luo, Y.; Gupta, R.; Hock, J.; Raparia, D.

    2011-03-28

    We designed two electron lenses to apply head-on beam-beam compensation for RHIC; they will be installed near IP10. The electron-beam transport system is an important subsystem of the entire electron-lens system. Electrons are transported from the electron gun to the main solenoid and further to the collector. The system must allow for changes of the electron beam size inside the superconducting magnet, and for changes of the electron position by 5 mm in the horizontal- and vertical-planes.

  18. Transformations in Air Transportation Systems For the 21st Century

    NASA Technical Reports Server (NTRS)

    Holmes, Bruce J.

    2004-01-01

    Globally, our transportation systems face increasingly discomforting realities: certain of the legacy air and ground infrastructures of the 20th century will not satisfy our 21st century mobility needs. The consequence of inaction is diminished quality of life and economic opportunity for those nations unable to transform from the 20th to 21st century systems. Clearly, new thinking is required regarding business models that cater to consumers value of time, airspace architectures that enable those new business models, and technology strategies for innovating at the system-of-networks level. This lecture proposes a structured way of thinking about transformation from the legacy systems of the 20th century toward new systems for the 21st century. The comparison and contrast between the legacy systems of the 20th century and the transformed systems of the 21st century provides insights into the structure of transformation of air transportation. Where the legacy systems tend to be analog (versus digital), centralized (versus distributed), and scheduled (versus on-demand) for example, transformed 21st century systems become capable of scalability through technological, business, and policy innovations. Where air mobility in our legacy systems of the 20th century brought economic opportunity and quality of life to large service markets, transformed air mobility of the 21st century becomes more equitable available to ever-thinner and widely distributed populations. Several technological developments in the traditional aircraft disciplines as well as in communication, navigation, surveillance and information systems create new foundations for 21st thinking about air transportation. One of the technological developments of importance arises from complexity science and modern network theory. Scale-free (i.e., scalable) networks represent a promising concept space for modeling airspace system architectures, and for assessing network performance in terms of robustness

  19. Space Transportation Systems Life Cycle Cost Assessment and Control

    NASA Technical Reports Server (NTRS)

    Robinson, John W.; Rhodes, Russell E.; Zapata, Edgar; Levack, Daniel J. H.; Donahue, Benjaamin B.; Knuth, William

    2008-01-01

    Civil and military applications of space transportation have been pursued for just over 50 years and there has been, and still is, a need for safe, dependable, affordable, and sustainable space transportation systems. Fully expendable and partially reusable space transportation systems have been developed and put in operation that have not adequately achieved this need. Access to space is technically achievable, but presently very expensive and will remain so until there is a breakthrough in the way we do business. Since 1991 the national Space Propulsion Synergy Team (SPST) has reviewed and assessed the lessons learned from the major U.S. space programs of the past decades focusing on what has been learned from the assessment and control of Life Cycle Cost (LCC) from these systems. This paper presents the results of a selected number of studies and analyses that have been conducted by the SPST addressing the need, as well as the solutions, for improvement in LCC. The major emphasis of the SPST processes is on developing the space transportation system requirements first (up front). These requirements must include both the usual system flight performance requirements and also the system functional requirements, including the infrastructure on Earth's surface, in-space and on the Moon and Mars surfaces to determine LCC. This paper describes the development of specific innovative engineering and management approaches and processes. This includes a focus on flight hardware maturity for reliability, ground operations approaches, and business processes between contractor and government organizations. A major change in program/project cost control is being proposed by the SPST to achieve a sustainable space transportation system LCC - controlling cost as a program metric in addition to the existing practice of controlling performance and weight. Without a firm requirement and methodically structured cost control, it is unlikely that an affordable and sustainable space

  20. Characterization of nucleoside transport systems in cultured rat epididymal epithelium.

    PubMed

    Leung, G P; Ward, J L; Wong, P Y; Tse, C M

    2001-05-01

    The nucleoside transport systems in cultured epididymal epithelium were characterized and found to be similar between the proximal (caput and corpus) and distal (cauda) regions of the epididymis. Functional studies revealed that 70% of the total nucleoside uptake was Na(+) dependent, while 30% was Na(+) independent. The Na(+)-independent nucleoside transport was mediated by both the equilibrative nitrobenzylthioinosine (NBMPR)-sensitive system (40%) and the NBMPR-insensitive system (60%), which was supported by a biphasic dose response to NBMPR inhibition. The Na(+)-dependent [(3)H]uridine uptake was selectively inhibited 80% by purine nucleosides, indicating that the purine nucleoside-selective N1 system is predominant. Since Na(+)-dependent [(3)H]guanosine uptake was inhibited by thymidine by 20% and Na(+)-dependent [(3)H]thymidine uptake was broadly inhibited by purine and pyrimidine nucleosides, this suggested the presence of the broadly selective N3 system accounting for 20% of Na(+)-dependent nucleoside uptake. Results of RT-PCR confirmed the presence of mRNA for equilibrative nucleoside transporter (ENT) 1, ENT2, and concentrative nucleoside transporter (CNT) 2 and the absence of CNT1. It is suggested that the nucleoside transporters in epididymis may be important for sperm maturation by regulating the extracellular concentration of adenosine in epididymal plasma. PMID:11287319

  1. Engineering intracellular active transport systems as in vivo biomolecular tools.

    SciTech Connect

    Bachand, George David; Carroll-Portillo, Amanda

    2006-11-01

    Active transport systems provide essential functions in terms of cell physiology and metastasis. These systems, however, are also co-opted by invading viruses, enabling directed transport of the virus to and from the cell's nucleus (i.e., the site of virus replication). Based on this concept, fundamentally new approaches for interrogating and manipulating the inner workings of living cells may be achievable by co-opting Nature's active transport systems as an in vivo biomolecular tool. The overall goal of this project was to investigate the ability to engineer kinesin-based transport systems for in vivo applications, specifically the collection of effector proteins (e.g., transcriptional regulators) within single cells. In the first part of this project, a chimeric fusion protein consisting of kinesin and a single chain variable fragment (scFv) of an antibody was successfully produced through a recombinant expression system. The kinesin-scFv retained both catalytic and antigenic functionality, enabling selective capture and transport of target antigens. The incorporation of a rabbit IgG-specific scFv into the kinesin established a generalized system for functionalizing kinesin with a wide range of target-selective antibodies raised in rabbits. The second objective was to develop methods of isolating the intact microtubule network from live cells as a platform for evaluating kinesin-based transport within the cytoskeletal architecture of a cell. Successful isolation of intact microtubule networks from two distinct cell types was demonstrated using glutaraldehyde and methanol fixation methods. This work provides a platform for inferring the ability of kinesin-scFv to function in vivo, and may also serve as a three-dimensional scaffold for evaluating and exploiting kinesin-based transport for nanotechnological applications. Overall, the technology developed in this project represents a first-step in engineering active transport system for in vivo applications. Further

  2. Differential effects of sucrose and auxin on localized phosphate deficiency-induced modulation of different traits of root system architecture in Arabidopsis.

    PubMed

    Jain, Ajay; Poling, Michael D; Karthikeyan, Athikkattuvalasu S; Blakeslee, Joshua J; Peer, Wendy A; Titapiwatanakun, Boosaree; Murphy, Angus S; Raghothama, Kashchandra G

    2007-05-01

    Phosphorus, one of the essential elements for plants, is often a limiting nutrient in soils. Low phosphate (Pi) availability induces sugar-dependent systemic expression of genes and modulates the root system architecture (RSA). Here, we present the differential effects of sucrose (Suc) and auxin on the Pi deficiency responses of the primary and lateral roots of Arabidopsis (Arabidopsis thaliana). Inhibition of primary root growth and loss of meristematic activity were evident in seedlings grown under Pi deficiency with or without Suc. Although auxin supplementation also inhibited primary root growth, loss of meristematic activity was observed specifically under Pi deficiency with or without Suc. The results suggested that Suc and auxin do not influence the mechanism involved in localized Pi sensing that regulates growth of the primary root and therefore delineates it from sugar-dependent systemic Pi starvation responses. However, the interaction between Pi and Suc was evident on the development of the lateral roots and root hairs in the seedlings grown under varying levels of Pi and Suc. Although the Pi+ Suc- condition suppressed lateral root development, induction of few laterals under the Pi- Suc- condition point to increased sensitivity of the roots to auxin during Pi deprivation. This was supported by expression analyses of DR5uidA, root basipetal transport assay of auxin, and RSA of the pgp19 mutant exhibiting reduced auxin transport. A significant increase in the number of lateral roots under the Pi- Suc- condition in the chalcone synthase mutant (tt4-2) indicated a potential role for flavonoids in auxin-mediated Pi deficiency-induced modulation of RSA. The study thus demonstrated differential roles of Suc and auxin in the developmental responses of ontogenetically distinct root traits during Pi deprivation. In addition, lack of cross talk between local and systemic Pi sensing as revealed by the seedlings grown under either the Pi- Suc- condition or in the

  3. Transportation routing analysis geographic information system -- TRAGIS, a multimodal transportation routing tool

    SciTech Connect

    Johnson, P.E.

    1995-12-31

    Over 15 years ago, Oak Ridge National Laboratory (ORNL) developed two transportation routing models: HIGHWAY, which predicts truck transportation routes, and INTERLINE, which predicts rail transportation routes. Subsequent modifications have been made to enhance each of these models. Some of these changes include population density information for routes, HM-164 routing regulations for highway route controlled quantities of radioactive materials (RAM) truck shipments, and inclusion of waterway routing into INTERLINE. The AIRPORT model, developed 2 years after the HIGHWAY and INTERLINE models, serves as an emergency response tool. This model identifies the nearest airports from a designated location. Currently, the AIRPORT model is inactive. The Transportation Management Division of the US Department of Energy held a Baseline Requirements Assessment Session on the HIGHWAY, INTERLINE, and AIRPORT models in April 1994 to bring together many users of these models and other experts in the transportation routing field to discuss these models and to decide on the capabilities that needed to be added. Of the many needs discussed, the primary one was to have the network databases within a geographic information system (GIS). As a result of the Baseline Requirements Session, the development of a new GIS model has been initiated. This paper will discuss the development of the new Transportation Routing Analysis GIS (TRAGIS) model at ORNL.

  4. Modeling Reactive Transport in Coupled Groundwater-Conduit Systems

    NASA Astrophysics Data System (ADS)

    Spiessl, S. M.; Sauter, M.; Zheng, C.; Viswanathan, H. S.

    2002-05-01

    Modeling reactive transport in coupled groundwater-conduit systems requires consideration of two transport time scales in the flow and transport models. Consider for example a subsurface mine consisting of a network of highly conductive shafts, drifts or ventilation raises (i.e., conduits) within the considerably less permeable ore material (i.e., matrix). In the conduits, potential contaminants can travel much more rapidly than in the background aquifer (matrix). Since conduits cannot necessarily be regarded as a continuum, double continuum models are only of limited use for simulation of contaminant transport in such coupled groundwater-conduit systems. This study utilizes a "hybrid" flow and transport model in which contaminants can in essence be transported at a slower time scale in the matrix and at a faster time scale in the conduits. The hybrid flow model uses an approach developed by Clemens et al. (1996), which is based on the modelling of flow in a discrete pipe network, coupled to a continuum representing the low-permeability inter-conduit matrix blocks. Laminar or turbulent flow can be simulated in the different pipes depending on the flow conditions in the model domain. The three-dimensional finite-difference groundwater flow model MODFLOW (Harbaugh and McDonald, 1996) is used to simulate flow in the continuum. Contaminant transport within the matrix is simulated with a continuum approach using the three-dimensional multi-species solute transport model MT3DMS (Zheng and Wang, 1999), while that in the conduit system is simulated with a one-dimensional advective transport model. As a first step for reactive transport modeling in such systems, only equilibrium reactions among multiple species are considered by coupling the hybrid transport model to a geochemical speciation package. An idealized mine network developed by Viswanathan and Sauter (2001) is used as a test problem in this study. The numerical experiment is based on reference date collected from

  5. Diversity of Specificity and Function of Phosphate Translocators in Various Plastids

    PubMed Central

    Heldt, Hans W.; Flügge, Ulf-Ingo; Borchert, Sieglinde

    1991-01-01

    This report gives a comparison of the specificity of phosphate translocators in various plastids. Whereas the phosphate translocator of the C3 plant spinach mediates a counter exchange between inorganic phosphate, dihydroxyacetone phosphate, and 3-phosphoglycerate, the phosphate translocators in chloroplasts from C4 and CAM plants transport phosphoenolpyruvate in addition to the above mentioned metabolites. In plastids from pea roots the phosphate translocator also transports glucose 6-phosphate. This diversity of phosphate translocators is discussed in view of the special functions of the various plastids. PMID:16667988

  6. Recent Advances in Understanding the Molecular Mechanisms Regulating the Root System Response to Phosphate Deficiency in Arabidopsis.

    PubMed

    Bouain, Nadia; Doumas, Patrick; Rouached, Hatem

    2016-08-01

    Phosphorus (P) is an essential macronutrient for plant growth and development. Inorganic phosphate (Pi) is the major form of P taken up from the soil by plant roots. It is well established that under Pi deficiency condition, plant roots undergo striking morphological changes; mainly a reduction in primary root length while increase in lateral root length as well as root hair length and density. This typical phenotypic change reflects complex interactions with other nutrients such as iron, and involves the activity of a large spectrum of plant hormones. Although, several key proteins involved in the regulation of root growth under Pi-deficiency have been identified in Arabidopsis, how plants adapt roots system architecture in response to Pi availability remains an open question. In the current post-genomic era, state of the art technologies like high-throughput phenotyping and sequencing platforms,"omics" methods, together with the widespread use of system biology and genome-wide association studies will help to elucidate the genetic architectures of root growth on different Pi regimes. It is clear that the large-scale characterization of molecular systems will improve our understanding of nutrient stress phenotype and biology. Herein, we summarize the recent advances and future directions towards a better understanding of Arabidopsis root developmental programs functional under Pi deficiency. Such a progress is necessary to devise strategies to improve the Pi use efficiency in plants that is an important issue for agriculture. PMID:27499680

  7. Macrophages require different nucleoside transport systems for proliferation and activation.

    PubMed

    Soler, C; García-Manteiga, J; Valdés, R; Xaus, J; Comalada, M; Casado, F J; Pastor-Anglada, M; Celada, A; Felipe, A

    2001-09-01

    To evaluate the mechanisms involved in macrophage proliferation and activation, we studied the regulation of the nucleoside transport systems. In murine bone marrow-derived macrophages, the nucleosides required for DNA and RNA synthesis are recruited from the extracellular medium. M-CSF induced macrophage proliferation and DNA and RNA synthesis, whereas interferon gamma (IFN-gamma) led to activation, blocked proliferation, and induced only RNA synthesis. Macrophages express at least the concentrative systems N1 and N2 (CNT2 and CNT1 genes, respectively) and the equilibrative systems es and ei (ENT1 and ENT2 genes, respectively). Incubation with M-CSF only up-regulated the equilibrative system es. Inhibition of this transport system blocked M-CSF-dependent proliferation. Treatment with IFN-gamma only induced the concentrative N1 and N2 systems. IFN-gamma also down-regulated the increased expression of the es equilibrative system induced by M-CSF. Thus, macrophage proliferation and activation require selective regulation of nucleoside transporters and may respond to specific requirements for DNA and RNA synthesis. This report also shows that the nucleoside transporters are critical for macrophage proliferation and activation. PMID:11532978

  8. GPS and GPRS Based Telemonitoring System for Emergency Patient Transportation.

    PubMed

    Satyanarayana, K; Sarma, A D; Sravan, J; Malini, M; Venkateswarlu, G

    2013-01-01

    Telemonitoring during the golden hour of patient transportation helps to improve medical care. Presently there are different physiological data acquisition and transmission systems using cellular network and radio communication links. Location monitoring systems and video transmission systems are also commercially available. The emergency patient transportation systems uniquely require transmission of data pertaining to the patient, vehicle, time of the call, physiological signals (like ECG, blood pressure, a body temperature, and blood oxygen saturation), location information, a snap shot of the patient, and voice. These requirements are presently met by using separate communication systems for voice, physiological data, and location that result in a lot of inconvenience to the technicians, maintenance related issues, in addition to being expensive. This paper presents design, development, and implementation of such a telemonitoring system for emergency patient transportation employing ARM 9 processor module. This system is found to be very useful for the emergency patient transportation being undertaken by organizations like the Emergency Management Research Institute (EMRI). PMID:27019844

  9. GPS and GPRS Based Telemonitoring System for Emergency Patient Transportation

    PubMed Central

    Satyanarayana, K.; Sarma, A. D.; Sravan, J.; Malini, M.; Venkateswarlu, G.

    2013-01-01

    Telemonitoring during the golden hour of patient transportation helps to improve medical care. Presently there are different physiological data acquisition and transmission systems using cellular network and radio communication links. Location monitoring systems and video transmission systems are also commercially available. The emergency patient transportation systems uniquely require transmission of data pertaining to the patient, vehicle, time of the call, physiological signals (like ECG, blood pressure, a body temperature, and blood oxygen saturation), location information, a snap shot of the patient, and voice. These requirements are presently met by using separate communication systems for voice, physiological data, and location that result in a lot of inconvenience to the technicians, maintenance related issues, in addition to being expensive. This paper presents design, development, and implementation of such a telemonitoring system for emergency patient transportation employing ARM 9 processor module. This system is found to be very useful for the emergency patient transportation being undertaken by organizations like the Emergency Management Research Institute (EMRI). PMID:27019844

  10. Geographic information system applications in coal transportation analysis

    SciTech Connect

    Elmes, G.

    1996-12-31

    Geographic information systems (GIS) offer great potential to the coal transportation industry for capitalizing on the growing availability of spatially-referenced data. As computer-based systems for the collection, storage, retrieval and analysis of spatial data, generating information products in a variety of formats, GIS have a great capability to improve the efficiency and effectiveness of coal transportation operations, planning, engineering, and facilities management. Currently GIS are used in the transportation industry at large to analyze, and display information about network infrastructure, fleet operations, property ownership, routing and scheduling, and utilities. Current coal transportation applications include consumer service inquiries, train and locomotive scheduling, and evaluation of network usage. The paper describes the significant potential uses of GIS in the coal transportation sector when integrated with optimization and decision support systems, scientific visualization, data forecasting, and strategic system planning approaches. Ultimately consumer demand and the drive for economic efficiency are likely to stimulate the integration and management of spatial information across the entire coal chain.

  11. Active and passive calcium transport systems in plant cells

    SciTech Connect

    Sze, H.

    1990-01-01

    The ability to change cytoplasmic Ca{sup 2+} levels ((Ca{sup 2+})) by cells has made this cation a key regulator of many biological processes. Cytoplasmic (Ca{sup 2+}) is determined by the coordination of passive Ca{sup 2+} fluxes which increase cytosolic (Ca{sup 2+}) and active Ca{sup 2+} transport systems that lower cytosolic (Ca{sup 2+}). The mechanisms by which plant cells achieve this is poorly understood. We have initially used isolated vesicles from the plasma membrane or organellar membranes to study Ca{sup 2+} transport systems in oat roots (a monocot) and carrot suspension cells (a dicot). The objectives of the proposal were to identify and characterize active (energy-dependent) and passive calcium transport systems that work together to regulate calcium levels in the cytoplasm of plant cells. 10 figs., 2 tabs.

  12. Active and passive calcium transport systems in plant cells

    SciTech Connect

    Sze, H.

    1991-01-01

    The ability to change cytoplasmic Ca{sup 2+} levels ((Ca{sup 2+})) by cells has made this cation a key regulator of many biological processes. Cytoplasmic (Ca{sup 2+}) is determined by the coordination of passive Ca{sup 2+} fluxes which increase cytosolic (Ca{sup 2+}) and active Ca{sup 2+} transport systems that lower cytosolic (Ca{sup 2+}). The mechanisms by which plant cells achieve this is poorly understood. We have initially used isolated vesicles from the plasma membrane or organellar membranes to study Ca{sup 2+} transport systems in oat roots (a monocot) and carrot suspension cells (a dicot). The objectives of the proposal were to identify and characterize active (energy-dependent) and passive calcium transport systems that work together to regulate calcium levels in the cytoplasm of plant cells.

  13. Feasibility study for a transportation operations system cask maintenance facility

    SciTech Connect

    Rennich, M.J.; Medley, L.G.; Attaway, C.R.

    1991-01-01

    The US Department of Energy (DOE), Office of Civilian Radioactive Waste Management (OCRWM) is responsible for the development of a waste management program for the disposition of spent nuclear fuel (SNF) and high-level waste (HLW). The program will include a transportation system for moving the nuclear waste from the sources to a geologic repository for permanent disposal. Specially designed casks will be used to safely transport the waste. The cask systems must be operated within limits imposed by DOE, the Nuclear Regulatory Commission (NRC), and the Department of Transportation (DOT). A dedicated facility for inspecting, testing, and maintaining the cask systems was recommended by the General Accounting Office (in 1979) as the best means of assuring their operational effectiveness and safety, as well as regulatory compliance. In November of 1987, OCRWM requested a feasibility study be made of a Cask Maintenance Facility (CMF) that would perform the required functions. 46 refs., 16 figs., 13 tabs.

  14. Regulatory mechanism of the three-component system HptRSA in glucose-6-phosphate uptake in Staphylococcus aureus.

    PubMed

    Yang, Yifan; Sun, Haipeng; Liu, Xiaoyu; Wang, Mingxing; Xue, Ting; Sun, Baolin

    2016-06-01

    Glucose-6-phosphate (G6P) is a common alternative carbon source for various bacteria, and its uptake usually relies on the hexose phosphate antiporter UhpT. In the human pathogenic bacterium Staphylococcus aureus, the ability to utilize different nutrients, particularly alternative carbon source uptake in glucose-limiting conditions, is essential for its fitness in the host environment during the infectious process. It has been reported that G6P uptake in S. aureus is regulated by the three-component system HptRSA. When G6P is provided as the only carbon source, HptRSA could sense extracellular G6P and activate uhpT expression to facilitate G6P utilization. However, the regulatory mechanism of HptRSA is still unclear. In this study, we further investigated the HptRSA system in S. aureus. First, we confirmed that HptRSA is necessary for the normal growth of this pathogen in chemically defined medium with G6P supplementation, and we discovered that HptRSA could exclusively sense extracellular G6P compared to the other organophosphates we tested. Next, using isothermal titration calorimetry, we found that HptA could bind to G6P, suggesting that it may be the G6P sensor. After that experiment, using an electrophoresis mobility shift assay, we verified that the response regulator HptR could directly bind to the uhpT promoter and identified a putative binding site from -67 to -96-bp. Subsequently, we created different point mutations in the putative binding site and revealed that the entire 30-bp sequence is essential for HptR regulation. In summary, we unveiled the regulatory mechanism of the HptRSA system in S. aureus, HptA most likely functions as the G6P sensor, and HptR could implement its regulatory function by directly binding to a conserved, approximately 30-bp sequence in the uhpT promoter. PMID:26711125

  15. Study of space transportation for space solar power systems

    NASA Astrophysics Data System (ADS)

    Kitamura, Shoji; Aoki, Hiroshi; Okawa, Yasushi; Taniguchi, Hirofumi

    2007-01-01

    Space solar power systems (SSPSs) have the potential to provide abundant quantities of electric power for use on the Earth. One of the hurdles to them is the transportation of SSPSs to the operational geostationary Earth orbit (GEO). The objectives of this study are to examine the transportation of SSPSs, and to give a reference transportation scenario. This study presumes that the SSPSs have a mass of 10,000 tons each and are constructed at a rate of one per year. Reusable launch vehicles (RLVs) are assumed for the transportation to low Earth orbit (LEO), and reusable orbit transfer vehicles (OTVs) propelled by a solar electric propulsion system for the transportation from LEO to GEO. The payload element delivered to LEO by each launch is individually transferred by each OTV transportation service to GEO, where the elements are assembled into a whole SSPS. The OTV round-trip time is assumed to be a year. With these operations and reasonable estimations for the OTV subsystems, the OTV payload ratio was obtained. This, with an SSPS element mass, gave the total mass that has to be launched by RLVs. The result indicated that about 300 times of launch are required per year.

  16. Code System to Calculate Tornado-Induced Flow Material Transport.

    SciTech Connect

    ANDRAE, R. W.

    1999-11-18

    Version: 00 TORAC models tornado-induced flows, pressures, and material transport within structures. Its use is directed toward nuclear fuel cycle facilities and their primary release pathway, the ventilation system. However, it is applicable to other structures and can model other airflow pathways within a facility. In a nuclear facility, this network system could include process cells, canyons, laboratory offices, corridors, and offgas systems. TORAC predicts flow through a network system that also includes ventilation system components such as filters, dampers, ducts, and blowers. These ventilation system components are connected to the rooms and corridors of the facility to form a complete network for moving air through the structure and, perhaps, maintaining pressure levels in certain areas. The material transport capability in TORAC is very basic and includes convection, depletion, entrainment, and filtration of material.

  17. Development of an analysis capability for the National Transportation System

    SciTech Connect

    Anson, D.; Nelson, R.

    1997-10-24

    The purpose of this report is to examine the Department of Transportation`s (DOT) National Transportation System (NTS) initiative, to document what has been learned, and to outline a National Transportation Network Analysis Capability (NTNAC) based on a ``TRANSIMS-like`` approach. This study was conducted over a two month period at the end of FY1997. The scope of the effort was carefully defined to accommodate the short time horizon and to provide focus to a very large analytical problem. The objectives were to: (1) define the NTS and the NTS problem; (2) identify problem characteristics; (3) describe an analytical solution based on the TRANSIMS approach; (4) identify data requirements and availability; (5) develop criteria for a scenario to be used in a prototype demonstration; and (6) select a scenario for the prototype demonstration.

  18. Perception and Expectation of Iran Neonatal Transport Expert Regard to Developing Neonatal Transport System in Iran: A Qualitative Research

    PubMed Central

    Hosseini, Mohammad-Bager; Jannati, Ali; Gholipour, Kamal; Heidarzadeh, Mohammad; Iezadi, Shabnam; Mojahed, Farokh; Vahidi, Reza Gholi

    2014-01-01

    Introduction: This study was aimed to reach expert's expectations of neonatal transport system for developing neonatal transport system in Iran. Materials and Methods: This is a qualitative study conducted by using focus group discussion (FGD) to present expert's perspectives and expectancy about neonatal transport system. Participants was selected from all experts and specialist about neonatal transport in Iran countryside. Finally 48 experts, participate in this study. To data collection 4 FGD were conducted, data were analyzed by content analyses. All subthemes were categorized in main themes according to conceptual relationship as an expert panels opinions. In order to comply with the ethical issues involved in the study was voluntary, also permission for the recording session were taken and confidentiality was also ensured. Result: According to FGD results, 11 themes and 90 subthemes were founded related to neonatal transport system, the main identified themes included: Aims, necessity and models of neonatal transport system, organizing the transport system, management and quality of instruments in the transport system, Neonatal transport system staff, Human resource management and issue related to human resources, conditions and requirements of neonatal transport system, facilitating factors in neonatal transport system, information management and communication system and weakness of neonatal transport system. Conclusion: Neonatal transport systems in different countries must adapted according to situation and component of each country have different strength and weakness and in implementing a system must attend to geographical conditions, financial ability and access to professionals, health system structure, facilities related to neonatal health care, antenatal services in regain, health care related, health care program about neonates and pregnant women and epidemiological status and mortality and morbidity in deferent locals and regains in countryside

  19. 76 FR 22940 - Intelligent Transportation Systems Program Advisory Committee; Notice of Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-25

    ... Intelligent Transportation Systems Program Advisory Committee; Notice of Meeting AGENCY: Research and... the Intelligent Transportation Systems (ITS) Program Advisory Committee (ITS PAC). The Web conference... Transportation on all matters relating to the study, development, and implementation of...

  20. 78 FR 64048 - Intelligent Transportation Systems Program Advisory Committee; Notice of Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-25

    ... Intelligent Transportation Systems Program Advisory Committee; Notice of Meeting AGENCY: ITS Joint Program...: Notice. The Intelligent Transportation Systems (ITS) Program Advisory Committee (ITSPAC) will hold a... Transportation on all matters relating to the study, development, and implementation of...