Association between serum alkaline phosphatase and coronary artery calcification in a sample of primary cardiovascular prevention patients.

PubMed

Panh, Loïc; Ruidavets, Jean Bernard; Rousseau, Hervé; Petermann, Antoine; Bongard, Vanina; Bérard, Emilie; Taraszkiewicz, Dorota; Lairez, Olivier; Galinier, Michel; Carrié, Didier; Ferrières, Jean

2017-05-01

A high level of serum alkaline phosphatase (ALP) is associated with an increased risk of mortality and myocardial infarction. ALP hydrolyses inorganic pyrophosphate, which is a strong inhibitor of calcium phosphate deposition. The aim of this study was to determine whether ALP is associated with the coronary artery calcium score (CACS). We examined the association of CACS, assessed by computed tomography scanning, and ALP, in 500 patients consecutively recruited, free of cardiovascular disease. The CACS were categorized into two groups: no calcification (CACS = 0) (n = 187) and with calcification (CACS>0) (n = 313). ALP activity was divided into three tertile groups: low ALP level (<55 IU/L), intermediate (55-66 IU/L) and high ALP level (>66 IU/L). The mean age was 60.9 ± 10.8 years, 49.6% of the patients were women. ALP ranged from 22 to 164 IU/L (mean 62.6 IU/L, SD 19.3). In univariate analysis, traditional cardiovascular risk factors, statin use (p = 0.001), and ALP (p = 0.001) were significantly associated with CACS. After adjusting for cardiovascular risk factors, only age (p = 0.001) and sex (p = 0.001) were independently associated with CACS. Compared to the tertile group with low levels of ALP, the intermediate tertile group [OR 2.11, 95% CI (1.12; 3.96), p = 0.02], as well as the high tertile group [OR 3.89, 95% CI (2.01; 7.54), p = 0.001)], was independently associated with CACS. In patients free of cardiovascular disease, high ALP levels are positively and independently associated with coronary artery calcification. The metabolic pathway of ALP and inorganic pyrophosphate could be a target for new therapies against vascular calcification. Copyright © 2017 Elsevier B.V. All rights reserved.

Degradation of cellulose under alkaline conditions: new insights from a 12 years degradation study.

PubMed

Glaus, Martin A; Van Loon, Luc R

2008-04-15

Cellulose degradation under alkaline conditions is of relevance to the mobility of many cations of the transition metal, lanthanide, and actinide series in the geosphere because strong complexants such as isosaccharinic acids, 3-deoxy-2-C-hydroxymethyl-D-erythro-pentonic acid (alpha-ISA) and 3-deoxy-2-C-hydroxymethyl-D-threo-pentonic acid (beta-ISA) may be formed. In the context of the long-term safety of cementitious repositories for low- and intermediate-level radioactive waste, where large amounts of cellulose may be present, the question of the time scales needed for the complete degradation of cellulose is important. The present paper reports the results of a 12 year study of the degradation of four different cellulosic materials (pure cellulose, tissue, cotton, paper) in an artificial cement pore water under anaerobic conditions at approximately 25 degrees C. The observed reaction characteristics can be divided into a fast reaction phase (2-3 years), dominated by the stepwise conversion of terminal glucose monomeric units to alpha-ISA and beta-ISA, and a very slow reaction phase during which the same products were found. The slow rate of the alkaline degradation of cellulose during this second reaction phase shows that previous kinetic models of cellulose degradation did not adequately describe the long-term behavior under alkaline conditions and need to be reassessed. It is postulated that a previously unknown mechanism by which crystalline or inaccessible reducing end groups of the polysaccharide chain become temporarily susceptible to alkaline attack is responsible for the slow rate of cellulose degradation.

Sources and reactivities of marine-derived organic matter in coastal sediments as determined by alkaline CuO oxidation

NASA Astrophysics Data System (ADS)

Goñi, Miguel A.; Hedges, John I.

1995-07-01

Alkaline CuO oxidation of ubiquitous biochemicals such as proteins, polysaccharides, and lipids, yields specific products, including fatty acids, diacids, and carboxylated phenols. Oxidation of a variety of marine organisms, including macrophytes, phytoplankton, zooplankton, and bacteria, yields these CuO products in characteristic patterns that can often differentiate these biological sources. Sediments from Skan Bay (Unalaska Island, Alaska) display organic carbon and total nitrogen profiles which are consistent with three kinetically distinct pools of organic matter. The CuO fingerprints of these sediments distinguish these three pools at the molecular level, indicating a highly labile, fatty acid-rich surface organic layer of likely bacterial origin, intermediately reactive kelp debris and a background of phytoplankton remains that predominates at depth. The CuO method, which has been previously applied only to characterize cutin and lignin constituents of vascular land plants, also provides information on other types of abundant biochemicals, including those indicative of marine sources.

In Silico Alkaline Hydrolysis of Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine: Density Functional Theory Investigation.

PubMed

Sviatenko, Liudmyla K; Gorb, Leonid; Hill, Frances C; Leszczynska, Danuta; Shukla, Manoj K; Okovytyy, Sergiy I; Hovorun, Dmytro; Leszczynski, Jerzy

2016-09-20

HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine), an energetic material used in military applications, may be released to the environment during manufacturing, transportation, storage, training, and disposal. A detailed investigation of a possible mechanism of alkaline hydrolysis, as one of the most promising methods for HMX remediation, was performed by computational study at PCM(Pauling)/M06-2X/6-311++G(d,p) level. Obtained results suggest that HMX hydrolysis at pH 10 represents a highly exothermic multistep process involving initial deprotonation and nitrite elimination, hydroxide attachment accompanied by cycle cleavage, and further decomposition of cycle-opened intermediate to the products caused by a series of C-N bond ruptures, hydroxide attachments, and proton transfers. Computationally predicted products of HMX hydrolysis such as nitrite, 4-nitro-2,4-diazabutanal, formaldehyde, nitrous oxide, formate, and ammonia correspond to experimentally observed species. Based on computed reaction pathways for HMX decomposition by alkaline hydrolysis, the kinetics of the entire process was modeled. Very low efficiency of this reaction at pH 10 was observed. Computations predict significant increases (orders of magnitude) of the hydrolysis rate for hydrolysis reactions undertaken at pH 11, 12, and 13.

Chemical Frustration in the Protein Folding Landscape: Grand Canonical Ensemble Simulations of Cytochrome c

PubMed Central

Weinkam, Patrick; Romesberg, Floyd E.; Wolynes, Peter G.

2010-01-01

A grand canonical formalism is developed to combine discrete simulations for chemically distinct species in equilibrium. Each simulation is based on a perturbed funneled landscape. The formalism is illustrated using the alkaline-induced transitions of cytochrome c as observed by FTIR spectroscopy and with various other experimental approaches. The grand canonical simulation method accounts for the acid/base chemistry of deprotonation, the inorganic chemistry of heme ligation and misligation, and the minimally frustrated folding energy landscape, thus elucidating the physics of protein folding involved with an acid/base titration of a protein. The formalism combines simulations for each of the relevant chemical species, varying by protonation and ligation states. In contrast to models based on perfectly funneled energy landscapes that contain only contacts found in the native structure, the current study introduces “chemical frustration” from deprotonation and misligation that gives rise to many intermediates at alkaline pH. While the nature of these intermediates cannot be easily inferred from available experimental data, the current study provides specific structural details of these intermediates thus extending our understanding of how cytochrome c changes with increasing pH. The results demonstrate the importance of chemical frustration for understanding biomolecular energy landscapes. PMID:19199810

Genetics of alkaline phosphatase of the small intestine of the house mouser (Mus musculus).

PubMed

Wilcox, F H

1983-08-01

Four inbred strains of mice exhibited either slow (PL/J), intermediate (DBA/2J, LP/J), or fast (SWR/J) rates of migration of duodenal alkaline phosphatase on cellulose acetate electrophoresis. Hybrids of these strains also had intermediate rates of migration regardless of the combination of strains used as parents. Strain differences were present in all regions of the small but not the large intestine. Crosses of the PL/J strain to hybrids between this strain and the other three strains gave a 1:1 segregation of the slow and intermediate patterns. The symbol Akp-3 is proposed for the locus responsible for the slower migration of the enzyme in this strain. Data from the LP/J X PL/J hybrid crossed with the PL/J strain showed linkage with two loci on chromosome 1 as follows: centromere--Idh-1--13.8 cM--Akp-3--8.9 +/- 2.6 cM--Pep-3. The available data do not reveal the genetic basis for the faster migration rate of the enzyme from the SWR/J strain, but a different response to neuraminidase and apparent nonlinkage to the Pep-3 locus suggest that a locus other than Akp-3 is responsible.

Ab initio study of the alkaline hydrolysis of a thio-β-lactam structure

NASA Astrophysics Data System (ADS)

Coll, Miguel; Frau, Juan; Vilanova, Bartolomé; Donoso, Josefa; Muñoz, Francisco

2000-08-01

The alkaline hydrolysis of a thio-β-lactam in the gas phase was examined in the light of RHF and DFT ab initio calculations. The solvent effect was considered via IPCM computations. The tetrahedral intermediate for the thio-β-lactam studied is unstable, so the compound evolves directly to the corresponding thio-azethidin-2-one open ring with cleavage of the C-S bond. The end-products obtained bear a carbamate group, which suggests that the thio-β-lactam might be an effective inhibitor for β-lactamases.

Impact of alkaline alterations to a Brazilian soil on cesium retention under low temperature conditions.

PubMed

Calábria, Jaqueline Alves de Almeida; Cota, Stela Dalva Santos; de Morais, Gustavo Ferrari; Ladeira, Ana Cláudia Queiroz

2017-11-01

To be used as backfilling materials in radioactive waste disposal facilities, a natural material must have a suitable permeability, mechanical properties and a high sorption capacity for radionuclides. Also important when considering a material as a backfill is the effect of its interaction with the alkaline solution generated from concrete degradation. This solution promotes mineralogical alterations that result in significant changes in the material key properties influencing its performance as a safety component of the repository. This paper presents results of an investigation on the effect of alkaline interaction under a low temperature on cesium retention properties of a local soil being considered suitable as a backfill for the Brazilian near surface disposal facility. A sample of the Brazilian soil was mixed with an alkaline solution, simulating the pore water leached in the first stage of cement degradation, during 1, 7, 14 and 28 days. The experiments were conducted under low temperature (25 °C) aiming to evaluate similar conditions found on a low and intermediate level radioactive waste disposal installation. A non-classical isotherm sorption model was fitted to sorption data obtained from batch experiments, for unaltered and altered samples, providing parameters that allowed us to assess the effect of the interaction on material quality as Cs sorbent. The sorption parameters obtained from the data-fitted isotherm were used then to estimate the corresponding retardation factor (R). Alkaline interaction significantly modified the soil sorption properties for Cs. The parameter Q, related to the maximum sorption capacity, as well as the affinity parameter (K) and the retardation coefficients became significantly smaller (about 1000 times for the R coefficient) after pretreatment with the simulated alkaline solutions. Moreover, the increase in n-values, which is related with the energy distribution width and heterogeneity of surface site energies, demonstrated that the adsorbent surface became more homogenous as a consequence of the alkaline alteration. Together these results suggest that cementitious leachate has a profound effect on Cs retention and should be accounted for estimating radionuclide retention in radioactive waste disposal systems containing cementitious materials. Copyright © 2017 Elsevier Ltd. All rights reserved.

Serum creatinine and alkaline phosphatase levels are associated with severe chronic periodontitis.

PubMed

Caúla, A L; Lira-Junior, R; Tinoco, E M B; Fischer, R G

2015-12-01

Periodontitis may alter systemic homeostasis and influence creatinine and alkaline phosphatase levels. Therefore, the aim of this study was to evaluate the relationship between severe chronic periodontitis and serum creatinine and alkaline phosphatase levels. One hundred patients were evaluated, 66 with severe chronic periodontitis (test group) and 34 periodontally healthy controls (control group). Medical, demographic and periodontal parameters were registered. Blood sample was collected after an overnight fast and serum creatinine and alkaline phosphatase levels were determined. There were significant differences between test and control groups in ethnicity, gender and educational level (p < 0.05). Patients with periodontitis showed a lower mean creatinine level (p < 0.05) and higher mean alkaline phosphatase level (p < 0.001) than the control group. There were significant correlations between periodontal parameters and serum creatinine and alkaline phosphatase levels. Severe chronic periodontitis was associated to lower creatinine and higher alkaline phosphatase levels. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Catalytic actions of alkaline salts in reactions between 1,2,3,4-butanetetracarboxylic acid and cellulose: II. Esterification.

PubMed

Ji, Bolin; Tang, Peixin; Yan, Kelu; Sun, Gang

2015-11-05

1,2,3,4-Butanetetracarboxylic acid (BTCA) reacts with cellulose in two steps with catalysis of alkaline salts such as sodium hypophosphite: anhydride formation and esterification of anhydride with cellulose. The alkali metal ions were found effective in catalyzing formation of BTCA anhydride in a previous report. In this work, catalytic functions of the alkaline salts in the esterification reaction between BTCA anhydride and cellulose were investigated. Results revealed that acid anions play an important role in the esterification reaction by assisting removal of protons on intermediates and completion of the esterification between cellulose and BTCA. Besides, alkaline salts with lower pKa1 values of the corresponding acids are more effective ones for the reaction since addition of these salts could lead to lower pH values and higher acid anion concentrations in finishing baths. The mechanism explains the results of FTIR and wrinkle recovery angles of the fabrics cured under different temperatures and times. Copyright © 2015 Elsevier Ltd. All rights reserved.

In Situ Infrared Spectroscopy of Oligoaniline Intermediates Created under Alkaline Conditions.

PubMed

Šeděnková, Ivana; Stejskal, Jaroslav; Trchová, Miroslava

2014-12-26

The progress of the oxidation of aniline with ammonium peroxydisulfate in an alkaline aqueous medium has been monitored in situ by attenuated total reflection (ATR) Fourier transform infrared spectroscopy. The growth of the microspheres and of the film at the ATR crystal surface, as well as the changes proceeding in the surrounding aqueous medium, are reflected in the spectra. The evolution of the spectra and the changes in the molecular structure occurring during aniline oxidation in alkaline medium are discussed with the help of differential spectra. Several processes connected with the various stages of aniline oxidation were distinguished. The progress of hydrolysis of the aniline in water and further an oxidation of aminophenol to benzoquinone imines in the presence of peroxydisulfate in alkaline medium have been detected in the spectra in real time. The precipitated solid oxidation product was analyzed by mass spectrometry. It is composed of oligomers, mainly trimers to octamers, of various molecular structures incorporating in addition to aniline constitutional units also p-benzoquinone or p-benzoquinoneimine moieties.

Size and performance of anoxic limestone drains to neutralize acdic mine drainagei

USGS Publications Warehouse

Cravotta, C.A.

2003-01-01

Acidic mine drainage (AMD) can be neutralized effectively in underground, anoxic limestone drains (ALDs). Owing to reaction between the AMD and limestone (CaCO3), the pH and concentrations of alkalinity and calcium increase asymptotically with detention time in the ALD, while concentrations of sulfate, ferrous iron, and manganese typically are unaffected. This paper introduces a method to predict the alkalinity produced within an ALD and to estimate the mass of limestone required for its construction on the basis of data from short-term, closed-container (cubitainer) tests. The cubitainer tests, which used an initial mass of 4 kg crushed limestone completely inundated with 2.8 L AMD, were conducted for 11 to 16 d and provided estimates for the initial and maximum alkalinities and corresponding rates of alkalinity production and limestone dissolution. Long-term (5-11 yr) data for alkalinity and CaCO3 flux at the Howe Bridge, Morrison, and Buck Mountain ALDs in Pennsylvania, USA, indicate that rates of alkalinity production and limestone dissolution under field conditions were comparable with those in cubitainers filled with limestone and AMD from each site. The alkalinity of effluent and intermediate samples along the flow path through the ALDs and long-term trends in the residual mass of limestone and the effluent alkalinity were estimated as a function of the computed detention time within the ALD and second-order dissolution rate models for cubitainer tests. Thus, cubitainer tests can be a useful tool for designing ALDs and predicting their performance.

Elucidation of the Oxygen Reduction Volcano in Alkaline Media using a Copper-Platinum(111) Alloy.

PubMed

Jensen, Kim D; Tymoczko, Jakub; Rossmeisl, Jan; Bandarenka, Aliaksandr S; Chorkendorff, Ib; Escudero-Escribano, María; Stephens, Ifan E L

2018-03-05

The relationship between the binding of the reaction intermediates and oxygen reduction activity in alkaline media was experimentally explored. By introducing Cu into the 2nd surface layer of a Pt(111) single crystal, the surface reactivity was tuned. In both 0.1 m NaOH and 0.1 m KOH, the optimal catalyst should exhibit OH binding circa 0.1 eV weaker than Pt(111), via a Sabatier volcano; this observation suggests that the reaction is mediated via the same surface bound intermediates as in acid, in contrast to previous reports. In 0.1 m KOH, the alloy catalyst at the peak of the volcano exhibits a maximum activity of 101±8 mA cm -2 at 0.9 V vs. a reversible hydrogen electrode (RHE). This activity constitutes a circa 60-fold increase over Pt(111) in 0.1 m HClO 4 . © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Alkaline biodegradable implants for osteoporotic bone defects--importance of microenvironment pH.

PubMed

Liu, W; Wang, T; Yang, C; Darvell, B W; Wu, J; Lin, K; Chang, J; Pan, H; Lu, W W

2016-01-01

Change of microenvironment pH by biodegradable implants may ameliorate unbalanced osteoporotic bone remodeling. The present work demonstrated that a weak alkaline condition stimulated osteoblasts differentiation while suppressed osteoclast generation. In vivo, implants with an alkaline microenvironment pH (monitored by a pH microelectrode) exhibited a promising healing effect for the repair of osteoporotic bone defects. Under osteoporotic conditions, the response of the bone microenvironment to an endosseous implant is significantly impaired, and this substantially increases the risk of fracture, non-union and aseptic implant loosening. Acid-base equilibrium is an important factor influencing bone cell behaviour. The present purpose was to study the effect of a series of alkaline biodegradable implant materials on regeneration of osteoporotic bone defect, monitoring the microenvironment pH (μe-pH) over time. The proliferation and differentiation potential of osteoporotic rat bone marrow stromal cells and RAW 264.7 cells were examined under various pH conditions. Ovariectomized rat bone defects were filled with specific biodegradable materials, and μe-pH was measured by pH microelectrode. New osteoid and tartrate-resistant acid phosphatase-positive osteoclast-like cells were examined by Goldner's trichrome and TRAP staining, respectively. The intermediate layer between implants and new bone were studied using energy-dispersive X-ray spectroscopy (EDX) linear scanning. In vitro, weak alkaline conditions stimulated osteoporotic rat bone marrow stromal cells (oBMSC) differentiation, while inhibiting the formation of osteoclasts. In vivo, μe-pH differs from that of the homogeneous peripheral blood and exhibits variations over time particular to each material. Higher initial μe-pH was associated with more new bone formation, late response of TRAP-positive osteoclast-like cells and the development of an intermediate 'apatitic' layer in vivo. EDX suggested that residual material may influence μe-pH even 9 weeks post-surgery. The pH microelectrode is suitable for in vivo μe-pH detection. Alkaline biodegradable materials generate an in vivo microenvironmental pH which is higher than the normal physiological value and show promising healing effects in the context of osteoporotic bone defects.

Microbial reduction of U(VI) under alkaline conditions: implications for radioactive waste geodisposal.

PubMed

Williamson, Adam J; Morris, Katherine; Law, Gareth T W; Rizoulis, Athanasios; Charnock, John M; Lloyd, Jonathan R

2014-11-18

Although there is consensus that microorganisms significantly influence uranium speciation and mobility in the subsurface under circumneutral conditions, microbiologically mediated U(VI) redox cycling under alkaline conditions relevant to the geological disposal of cementitious intermediate level radioactive waste, remains unexplored. Here, we describe microcosm experiments that investigate the biogeochemical fate of U(VI) at pH 10-10.5, using sediments from a legacy lime working site, stimulated with an added electron donor, and incubated in the presence and absence of added Fe(III) as ferrihydrite. In systems without added Fe(III), partial U(VI) reduction occurred, forming a U(IV)-bearing non-uraninite phase which underwent reoxidation in the presence of air (O2) and to some extent nitrate. By contrast, in the presence of added Fe(III), U(VI) was first removed from solution by sorption to the Fe(III) mineral, followed by bioreduction and (bio)magnetite formation coupled to formation of a complex U(IV)-bearing phase with uraninite present, which also underwent air (O2) and partial nitrate reoxidation. 16S rRNA gene pyrosequencing showed that Gram-positive bacteria affiliated with the Firmicutes and Bacteroidetes dominated in the post-reduction sediments. These data provide the first insights into uranium biogeochemistry at high pH and have significant implications for the long-term fate of uranium in geological disposal in both engineered barrier systems and the alkaline, chemically disturbed geosphere.

Biodegradation of the alkaline cellulose degradation products generated during radioactive waste disposal.

PubMed

Rout, Simon P; Radford, Jessica; Laws, Andrew P; Sweeney, Francis; Elmekawy, Ahmed; Gillie, Lisa J; Humphreys, Paul N

2014-01-01

The anoxic, alkaline hydrolysis of cellulosic materials generates a range of cellulose degradation products (CDP) including α and β forms of isosaccharinic acid (ISA) and is expected to occur in radioactive waste disposal sites receiving intermediate level radioactive wastes. The generation of ISA's is of particular relevance to the disposal of these wastes since they are able to form complexes with radioelements such as Pu enhancing their migration. This study demonstrates that microbial communities present in near-surface anoxic sediments are able to degrade CDP including both forms of ISA via iron reduction, sulphate reduction and methanogenesis, without any prior exposure to these substrates. No significant difference (n = 6, p = 0.118) in α and β ISA degradation rates were seen under either iron reducing, sulphate reducing or methanogenic conditions, giving an overall mean degradation rate of 4.7 × 10(-2) hr(-1) (SE ± 2.9 × 10(-3)). These results suggest that a radioactive waste disposal site is likely to be colonised by organisms able to degrade CDP and associated ISA's during the construction and operational phase of the facility.

Unified mechanism of alkali and alkaline earth catalyzed gasification reactions of carbon by CO2 and H2O

USGS Publications Warehouse

Chen, S.G.; Yang, R.T.

1997-01-01

From molecular orbital calculations, a unified mechanism is proposed for the gasification reactions of graphite by CO2 and H2O, both uncatalyzed and catalyzed by alkali and alkaline earth catalysts. In this mechanism, there are two types of oxygen intermediates that are bonded to the active edge carbon atoms: an in-plane semiquinone type, Cf(O), and an off-plane oxygen bonded to two saturated carbon atoms that are adjacent to the semiquinone species, C(O)Cf(O). The rate-limiting step is the decomposition of these intermediates by breaking the C-C bonds that are connected to Cf(O). A new rate equation is derived for the uncatalyzed reactions, and that for the catalyzed reactions is readily available from the proposed mechanism. The proposed mechanism can account for several unresolved experimental observations: TPD and TK (transient kinetics) desorption results of the catalyzed systems, the similar activation energies for the uncatalyzed and catalyzed reactions, and the relative activities of the alkali and alkaline earth elements. The net charge of the edge carbon active site is substantially changed by gaining electron density from the alkali or alkaline earth element (by forming C-O-M, where M stands for metal). The relative catalytic activities of these elements can be correlated with their abilities of donating electrons and changing the net charge of the edge carbon atom. As shown previously (Chen, S. G.; Yang, R. T. J. Catal. 1993, 141, 102), only clusters of the alkali compounds are active. This derives from the ability of the clusters to dissociate CO2 and H2O to form O atoms and the mobility of the dissociated O atoms facilitated by the clusters.

Site Occupation of Eu2+ in Ba2- xSr xSiO4 ( x = 0-1.9) and Origin of Improved Luminescence Thermal Stability in the Intermediate Composition.

PubMed

Lin, Litian; Ning, Lixin; Zhou, Rongfu; Jiang, Chunyan; Peng, Mingying; Huang, Yucheng; Chen, Jun; Huang, Yan; Tao, Ye; Liang, Hongbin

2018-06-18

Knowledge of site occupation of activators in phosphors is of essential importance for understanding and tailoring their luminescence properties by modifying the host composition. Relative site preference of Eu 2+ for the two distinct types of alkaline earth (AE) sites in Ba 1.9995- x Sr x Eu 0.0005 SiO 4 ( x = 0-1.9) is investigated based on photoluminescence measurements at low temperature. We found that Eu 2+ prefers to be at the 9-coordinated AE2 site at x = 0, 0.5, and 1.0, while at x = 1.5 and 1.9, it also occupies the 10-coordinated AE1 site with comparable preference, which is verified by density functional theory (DFT) calculations. Moreover, by combining low-temperature measurements of the heat capacity, the host band gap, and the Eu 2+ 4f 7 ground level position, the improved thermal stability of Eu 2+ luminescence in the intermediate composition ( x = 1.0) is interpreted as due to an enlarged energy gap between the emitting 5d level and the bottom of the host conduction band (CB), which results in a decreased nonradiative probability of thermal ionization of the 5d electron into the host CB. Radioluminescence properties of the samples under X-ray excitation are finally evaluated, suggesting a great potential scintillator application of the compound in the intermediate composition.

Alkaline phosphatase levels in patients with coronary heart disease saliva and its relation with periodontal status

NASA Astrophysics Data System (ADS)

Yunita, Dina Suci; Masulili, Sri Lelyati C.; Tadjoedin, Fatimah M.; Radi, Basuni

2017-02-01

Coronary heart disease (CHD) is a disease that causes narrowing of the coronary arteries. Currently, there is a hypothesis regarding periodontal infection that increases risk for heart disease. Alkaline phosphatase (ALP) as a marker of inflammation will increase in atherosclerosis and periodontal disease. The objective of this research is analyzing the relationship between the levels of alkaline phosphatase in saliva with periodontal status in patients with CHD and non CHD. Here, saliva of 104 subjects were taken, each 1 ml, and levels of Alkaline Phosphatase was analyzed using Abbott ci4100 architect. We found that no significant difference of Alkaline Phosphatase levels in saliva between CHD patients and non CHD. Therefore, it can be concluded that Alkaline Phosphatase levels in patients with CHD saliva was higher than non CHD and no association between ALP levels with periodontal status.

Prebiotic Peptide (Amide) Bond Synthesis Accelerated by Glycerol and Bicarbonate Under Neutral to Alkaline Dry-Down Conditions

NASA Technical Reports Server (NTRS)

Forsythe, J. G.; Weber, A. L.

2017-01-01

Past studies of prebiotic peptide bond synthesis have generally been carried out in the acidic to neutral pH range [1, 2]. Here we report a new process for peptide bond (amide) synthesis in the neutral to alkaline pH range that involves simple dry-down heating of amino acids in the presence of glycerol and bicarbonate. Glycerol was included in the reaction mixture as a solvent and to provide hydroxyl groups for possible formation of ester intermediates previously implicated in peptide bond synthesis under acidic to neutral conditions [1]. Bicarbonate was added to raise the reaction pH to 8-9.

Neogene-Quaternary Volcanic forms in the Carpathian-Pannonian Region: a review

NASA Astrophysics Data System (ADS)

Lexa, Jaroslav; Seghedi, Ioan; Németh, Karoly; Szakács, Alexandru; Koneĉny, Vlastimil; Pécskay, Zoltan; Fülöp, Alexandrina; Kovacs, Marinel

2010-09-01

Neogene to Quaternary volcanic/magmatic activity in the Carpathian-Pannonian Region (CPR) occurred between 21 and 0.1 Ma with a distinct migration in time from west to east. It shows a diverse compositional variation in response to a complex interplay of subduction with rollback, back-arc extension, collision, slab break-off, delamination, strike-slip tectonics and microplate rotations, as well as in response to further evolution of magmas in the crustal environment by processes of differentiation, crustal contamination, anatexis and magma mixing. Since most of the primary volcanic forms have been affected by erosion, especially in areas of post-volcanic uplift, based on the level of erosion we distinguish: (1) areas eroded to the basement level, where paleovolcanic reconstruction is not possible; (2) deeply eroded volcanic forms with secondary morphology and possible paleovolcanic reconstruction; (3) eroded volcanic forms with remnants of original morphology preserved; and (4) the least eroded volcanic forms with original morphology quite well preserved. The large variety of volcanic forms present in the area can be grouped in a) monogenetic volcanoes and b) polygenetic volcanoes and their subsurface/intrusive counterparts that belong to various rock series found in the CPR such as calc-alkaline magmatic rock-types (felsic, intermediate and mafic varieties) and alkalic types including K-alkalic, shoshonitic, ultrapotassic and Na-alkalic. The following volcanic/subvolcanic forms have been identified: (i) domes, shield volcanoes, effusive cones, pyroclastic cones, stratovolcanoes and calderas with associated intrusive bodies for intermediate and basic calclkaline volcanism; (ii) domes, calderas and ignimbrite/ash-flow fields for felsic calc-alkaline volcanism and (iii) dome flows, shield volcanoes, maars, tuffcone/tuff-rings, scoria-cones with or without related lava flow/field and their erosional or subsurface forms (necks/ plugs, dykes, shallow intrusions, diatreme, lava lake) for various types of K- and Na-alkalic and ultra-potassic magmatism. Finally, we provide a summary of the eruptive history and distribution of volcanic forms in the CPR using several sub-region schemes.

Reduction of nitrobenzene with alkaline ascorbic acid: Kinetics and pathways.

PubMed

Liang, Chenju; Lin, Ya-Ting; Shiu, Jia-Wei

2016-01-25

Alkaline ascorbic acid (AA) exhibits the potential to reductively degrade nitrobenzene (NB), which is the simplest of the nitroaromatic compounds. The nitro group (NO2(-)) of NB has a +III oxidation state of the N atom and tends to gain electrons. The effect of alkaline pH ranging from 9 to 13 was initially assessed and the results demonstrated that the solution pH, when approaching or above the pKa2 of AA (11.79), would increase reductive electron transfer to NB. The rate equation for the reactions between NB and AA at pH 12 can be described as r=((0.89±0.11)×10(-4) mM(1-(a+b))h(-1))×[NB](a=1.35±0.10)[AA](b=0.89±0.01). The GC/MS analytical method identified nitrosobenzene, azoxybenzene, and azobenzene as NB reduction intermediates, and aniline (AN) as a final product. These experimental results indicate that the alkaline AA reduction of NB to AN mainly proceeds via the direct route, consisting of a series of two-electron or four-electron transfers, and the condensation reaction plays a minor route. Preliminary evaluation of the remediation of spiked NB contaminated soils revealed that maintenance of alkaline pH and a higher water to soil ratio are essential for a successful alkaline AA application. Copyright © 2015 Elsevier B.V. All rights reserved.

Peroxidase-type reactions suggest a heterolytic/nucleophilic O–O joining mechanism in the heme-dependent chlorite dismutase†

PubMed Central

Mayfield, Jeffrey A.; Blanc, Béatrice; Rodgers, Kenton R.; Lukat-Rodgers, Gudrun S.; DuBois, Jennifer L.

2015-01-01

Heme-containing chlorite dismutases (Clds) catalyze a highly unusual O–O bond forming reaction. The O–O cleaving reactions of hydrogen peroxide and peracetic acid (PAA) with the Cld from Dechloromonas aromatica (DaCld) were studied to better understand the Cl–O cleavage of the natural substrate and subsequent O–O bond formation. While reactions with H2O2 resulted in slow destruction of the heme, at acidic pH, heterolytic cleavage of the O–O bond of PAA cleanly yielded the ferryl porphyrin cation radical (Compound I). At alkaline pH, the reaction proceeds more rapidly and the first observed intermediate is a ferryl heme. Freezequench EPR confirmed that the latter has an uncoupled protein-based radical, indicating that Compound I is the first intermediate formed at all pH values and that radical migration is faster at alkaline pH. These results suggest by analogy that two-electron Cl–O bond cleavage to yield a ferryl-porphyrin cation radical is the most likely initial step in O–O bond formation from chlorite. PMID:24001266

Origin of metaluminous and alkaline volcanic rocks of the Latir volcanic field, northern Rio Grande rift, New Mexico

USGS Publications Warehouse

Johnson, C.M.; Lipman, P.W.

1988-01-01

Volcanic rocks of the Latir volcanic field evolved in an open system by crystal fractionation, magma mixing, and crustal assimilation. Early high-SiO2 rhyolites (28.5 Ma) fractionated from intermediate compositionmagmas that did not reach the surface. Most precaldera lavas have intermediate-compositions, from olivine basaltic-andesite (53% SiO2) to quartz latite (67% SiO2). The precaldera intermediate-composition lavas have anomalously high Ni and MgO contents and reversely zoned hornblende and augite phenocrysts, indicating mixing between primitive basalts and fractionated magmas. Isotopic data indicate that all of the intermediate-composition rocks studied contain large crustal components, although xenocrysts are found only in one unit. Inception of alkaline magmatism (alkalic dacite to high-SiO2 peralkaline rhyolite) correlates with, initiation of regional extension approximately 26 Ma ago. The Questa caldera formed 26.5 Ma ago upon eruption of the >500 km3 high-SiO2 peralkaline Amalia Tuff. Phenocryst compositions preserved in the cogenetic peralkaline granite suggest that the Amalia Tuff magma initially formed from a trace element-enriched, high-alkali metaluminous magma; isotopic data suggest that the parental magmas contain a large crustal component. Degassing of water- and halogen-rich alkali basalts may have provided sufficient volatile transport of alkalis and other elements into the overlying silicic magma chamber to drive the Amalia Tuff magma to peralkaline compositions. Trace element variations within the Amalia Tuff itself may be explained solely by 75% crystal fractionation of the observed phenocrysts. Crystal settling, however, is inconsistent with mineralogical variations in the tuff, and crystallization is thought to have occurred at a level below that tapped by the eruption. Spatially associated Miocene (15-11 Ma) lavas did not assimilate large amounts of crust or mix with primitive basaltic magmas. Both mixing and crustal assimilation processes appear to require development of relatively large magma chambers in the crust that are sustained by large basalt fluxes from the mantle. The lack of extensive crustal contamination and mixing in the Miocene lavas may be related to a decreased basalt flux or initiation of blockfaulting that prevented pooling of basaltic magma in the crust. ?? 1988 Springer-Verlag.

Alkalinity-salinity relationship in the Chesapeake Bay

NASA Astrophysics Data System (ADS)

Cintrón Del Valle, S. M.; Najjar, R.; Herrmann, M.; Goldberger, S.; Stets, E.

2016-12-01

Estuaries are a significant source of atmospheric CO2, a major greenhouse gas. However, it is not known whether the Chesapeake Bay, the largest estuary in the United States, is a source or sink of CO2. Extensive pH measurements in the Bay offer the possibility of estimating the air-water CO2 flux if robust relationships between alkalinity, the acid neutralizing capacity of a water body, and salinity can be established. Here we conduct a comprehensive analysis of the alkalinity-salinity relationship in the Chesapeake Bay based on more than 18,000 alkalinity measurements made between 1985 and 2015. It was found that seven segments of the Bay could be grouped into three different linear functions, suggesting that alkalinity is conserved in the Bay and has properties that change depending on the freshwater endmember (the riverine source). The highest freshwater endmember was 1.21 mol m-3 for the Potomac River, the lowest one was 0.41 mol m-3 for the York and Rappahannock Rivers, and an intermediate freshwater endmember was 0.79 mol m-3 for the remaining four segments. For some segments, most notably the Potomac River, the scatter of the data increases with decreasing salinity, which is due, in part, to seasonal and interannual variations in the freshwater endmember.

Prophylactic treatment with alkaline phosphatase in cardiac surgery induces endogenous alkaline phosphatase release.

PubMed

Kats, Suzanne; Brands, Ruud; Hamad, Mohamed A Soliman; Seinen, Willem; Scharnhorst, Volkher; Wulkan, Raymond W; Schönberger, Jacques P; Oeveren, Wim van

2012-02-01

Laboratory and clinical data have implicated endotoxin as an important factor in the inflammatory response to cardiopulmonary bypass. We assessed the effects of the administration of bovine intestinal alkaline phosphatase (bIAP), an endotoxin detoxifier, on alkaline phosphatase levels in patients undergoing coronary artery bypass grafting. A total of 63 patients undergoing coronary artery bypass grafting were enrolled and prospectively randomized. Bovine intestinal alkaline phosphatase (n=32) or placebo (n=31) was administered as an intravenous bolus followed by continuous infusion for 36 hours. The primary endpoint was to evaluate alkaline phosphatase levels in both groups and to find out if administration of bIAP to patients undergoing CABG would lead to endogenous alkaline phosphatase release. No significant adverse effects were identified in either group. In all the 32 patients of the bIAP-treated group, we found an initial rise of plasma alkaline phosphatase levels due to bolus administration (464.27±176.17 IU/L). A significant increase of plasma alkaline phosphatase at 4-6 hours postoperatively was observed (354.97±95.00 IU/L) as well. Using LHA inhibition, it was shown that this second peak was caused by the generation of tissue non specific alkaline phosphatase (TNSALP-type alkaline phosphatase). Intravenous bolus administration plus 8 hours continuous infusion of alkaline phosphatase in patients undergoing coronary artery bypass grafting with cardiopulmonary bypass results in endogenous alkaline phosphatase release. This endogenous alkaline phosphatase may play a role in the immune defense system.

Carbonate system parameters and anthropogenic CO2 in the North Aegean Sea during October 2013

NASA Astrophysics Data System (ADS)

Krasakopoulou, E.; Souvermezoglou, E.; Giannoudi, L.; Goyet, C.

2017-10-01

Data of AT (total alkalinity) and CT (total inorganic carbon) collected during October 2013, on a N-S transect crossing the North of Lemnos basin allowed to identify the peculiarities of the CO2 system in the North Aegean Sea and estimate the anthropogenic CO2 (CANT) concentrations. Extremely high concentrations of AT and CT were recorded in the upper layer of the North Aegean reflecting the high loads of AT and CT by the brackish BSW (Black Sea Water) outflowing through the Dardanelles strait and by the rivers runoff. Both AT and CT exhibit strong negative linear correlation with salinity in the upper layer (0-20 m). Investigation of the AT-S relationship along with the salinity adjustment of AT revealed excess alkalinity throughout the water column in relation to the surface waters implying a possible occurrence of non-carbonate alkalinity inputs as well as of other processes that take place probably over the extended shelves and contribute to the alkalinity surplus. The intermediate layer occupied by the Modified Levantine Intermediate Water (MLIW) mass exhibits the lowest CT and AT concentrations, while rather elevated AT and CT concentrations characterize the North Aegean Deep Water (NAgDW) mass filling the deep layer of the North of Lemnos basin linked to previous dense water formation episodes. High anthropogenic CO2 content was detected at intermediate and deep layers of the North Aegean reflecting the effective transportation of the absorbed atmospheric CO2 from the surface to the deeper waters via the dense water formation episodes. The MLIW layer is more affected by the penetration of CANT than the NAgDW that fills the deep part of the basin. The observed variability of CANT distribution reflects the influence of the intensity of dense water formation events, of the different θ/S properties of the newly formed dense waters as well as of the diverse submarine pathways followed by the cascading dense waters. The invasion of CANT has lead to more acidic conditions and to lower saturation degree of calcium carbonate in relation to the preindustrial era. The findings of this study provide baseline information about the carbonate system properties of the North Aegean and highlight its active role in sequestering and storing anthropogenic CO2.

Immobilisation of hydroxyapatite-collagen on polydopamine grafted stainless steel 316L: Coating adhesion and in vitro cells evaluation.

PubMed

Tapsir, Zafirah; Jamaludin, Farah H; Pingguan-Murphy, Belinda; Saidin, Syafiqah

2018-02-01

The utilisation of hydroxyapatite and collagen as bioactive coating materials could enhance cells attachment, proliferation and osseointegration. However, most methods to form crystal hydroxyapatite coating do not allow the incorporation of polymer/organic compound due to production phase of high sintering temperature. In this study, a polydopamine film was used as an intermediate layer to immobilise hydroxyapatite-collagen without the introduction of high sintering temperature. The surface roughness, coating adhesion, bioactivity and osteoblast attachment on the hydroxyapatite-collagen coating were assessed as these properties remains unknown on the polydopamine grafted film. The coating was developed by grafting stainless steel 316L disks with a polydopamine film. Collagen type I fibres were then immobilised on the grafted film, followed by the biomineralisation of hydroxyapatite. The surface roughness and coating adhesion analyses were later performed by using AFM instrument. An Alamar Blue assay was used to determine the cytotoxicity of the coating, while an alkaline phosphatase activity test was conducted to evaluate the osteogenic differentiation of human fetal osteoblasts on the coating. Finally, the morphology of cells attachment on the coating was visualised under FESEM. The highest RMS roughness and coating adhesion were observed on the hydroxyapatite-collagen coating (hydroxyapatite-coll-dopa). The hydroxyapatite-coll-dopa coating was non-toxic to the osteoblast cells with greater cells proliferation, greater level of alkaline phosphate production and more cells attachment. These results indicate that the immobilisation of hydroxyapatite and collagen using an intermediate polydopamine is identical to enhance coating adhesion, osteoblast cells attachment, proliferation and differentiation, and thus could be implemented as a coating material on orthopaedic and dental implants.

Diagenetic Iron Cycling in Ancient Alkaline Saline Lacustrine Sedimentary Rocks: A Case Study on the Jurassic Brushy Basin Member of the Morrison Formation, Colorado Plateau, USA

NASA Astrophysics Data System (ADS)

Potter-McIntyre, S. L.; Chan, M. A.; McPherson, B. J. O. L.

2014-12-01

The upper part of the Brushy Basin Member in the Four Corners region of the U.S. was deposited in an ephemeral alkaline saline lake system with copious input of volcanic ash. The variegated shale formation provides a setting for the study of early diagenetic iron cycling that records the action of alkaline saline fluid chemistries reacting with volcaniclastic sediments in the presence of microbes. A bull's-eye pattern of authigenic minerals with increasing alteration towards the basinal center similar to modern alkaline saline lakes provides evidence for an extreme paleoenvironmental interpretation. The purpose of this research is to document specific factors, such as reactive sediments, microbial influences, and grain size that affect concretion formation and iron cycling in an ancient extreme environment. Three broad diagenetic facies are interpreted by color and associated bioturbation features: red, green and intermediate. Diagenetic facies reflect meter-scale paleotopography: red facies represent shallow water to subaerial, oxidizing conditions; green facies reflect saturated conditions and reducing pore water chemistry shortly after deposition, and intermediate facies represent a combination of the previous two conditions. Evidence of biotic influence is abundant and trace fossils exhibit patterns associated with the diagenetic facies. Red diagenetic facies typically contain burrows and root traces and green diagenetic facies exhibit restricted biotic diversity typically limited to algal molds (vugs). Microbial fossils are well-preserved and are in close proximity to specific iron mineral textures suggesting biotic influence on the crystal morphology. Three categories of concretions are characterized based on mineralogy: carbonate, iron (oxyhydr)oxide and phosphate concretions. Concretion mineralogy and size vary within an outcrop and even within a stratigraphic horizon such that more than one main category is typically present in an outcrop. Variation in concretion mineralogy and morphology within the Brushy Basin Member suggests that alkaline saline fluid chemistries in concert with microbial interaction created diagenetic microenvironments within a larger lake system to influence iron cycling and these reactions can be spatially variable even on 10s of cm scales.

An Aurivillius Oxide Based Cathode with Excellent CO2 Tolerance for Intermediate-Temperature Solid Oxide Fuel Cells.

PubMed

Zhu, Yinlong; Zhou, Wei; Chen, Yubo; Shao, Zongping

2016-07-25

The Aurivillius oxide Bi2 Sr2 Nb2 MnO12-δ (BSNM) was used as a cobalt-free cathode for intermediate-temperature solid oxide fuel cells (IT-SOFCs). To the best of our knowledge, the BSNM oxide is the only alkaline-earth-containing cathode material with complete CO2 tolerance that has been reported thus far. BSNM not only shows favorable activity in the oxygen reduction reaction (ORR) at intermediate temperatures but also exhibits a low thermal expansion coefficient, excellent structural stability, and good chemical compatibility with the electrolyte. These features highlight the potential of the new BSNM material as a highly promising cathode material for IT-SOFCs. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Theoretical study of the alkaline hydrolysis of an aza-β-lactam derivative of clavulanic acid

NASA Astrophysics Data System (ADS)

Garcías, Rafael C.; Coll, Miguel; Donoso, Josefa; Muñoz, Francisco

2003-04-01

DFT calculations based on the hybrid functional B3LYP/6-31+G * were used to study the alkaline hydrolysis of an aza-clavulanic acid, which results from the substitution of the carbon atom at position 6 in clavulanic acid by a nitrogen atom. The presence of the nitrogen atom endows the compound with special properties; in fact, once formed, the tetrahedral intermediate can evolve with cleavage of the N 4-C 7 or N 6-C 7 bond, which obviously leads to different reaction products. These differential bond cleavages may play a central role in the inactivation of β-lactamases, so the compound may be a powerful inactivator of these enzymes.

The Epoxidation of 2,5-Di-tert-butyl-1,4-benzoquinone: A Consecutive Reaction for the Physical Chemistry Laboratory.

ERIC Educational Resources Information Center

Hairfield, E. M.; And Others

1985-01-01

Reports a consecutive first-order reaction for which the concentrations of reactant, intermediate, and products can be determined simulataneously. This reaction is the epoxidation of 2,5-di-tert-butyl-1,4-benzoquinone (I) by alkaline hydroperoxidation using tert-butyl hydroperoxide and benzyltrimethylammonium hydroxide (Triton B) catalyst.…

A Molecular Cobalt Catalyst Architected and TiO2 Modified p-GaInP2 Photoelectrode for Hydrogen Production

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gu, Jing; Yan, Yong; Young, James

2017-05-01

We demonstrate that by employing a hybrid molecular/semiconductor interface with atomic layer deposited (ALD) TiO2 as an intermediate layer, a robust and corrosion resistant GaInP2-TiO2-cobaltoxime-TiO2 photocathode can be operated in alkaline media (pH =13).

Ascorbic acid induces alkaline phosphatase, type X collagen, and calcium deposition in cultured chick chondrocytes.

PubMed

Leboy, P S; Vaias, L; Uschmann, B; Golub, E; Adams, S L; Pacifici, M

1989-10-15

During the process of endochondral bone formation, proliferating chondrocytes give rise to hypertrophic chondrocytes, which then deposit a mineralized matrix to form calcified cartilage. Chondrocyte hypertrophy and matrix mineralization are associated with expression of type X collagen and the induction of high levels of the bone/liver/kidney isozyme of alkaline phosphatase. To determine what role vitamin C plays in these processes, chondrocytes derived from the cephalic portion of 14-day chick embryo sternae were grown in the absence or presence of exogenous ascorbic acid. Control untreated cells displayed low levels of type X collagen and alkaline phosphatase activity throughout the culture period. However, cells grown in the presence of ascorbic acid produced increasing levels of alkaline phosphatase activity and type X collagen mRNA and protein. Both alkaline phosphatase activity and type X collagen mRNA levels began to increase within 24 h of ascorbate treatment; by 9 days, the levels of both alkaline phosphatase activity and type X collagen mRNA were 15-20-fold higher than in non-ascorbate-treated cells. Ascorbate treatment also increased calcium deposition in the cell layer and decreased the levels of types II and IX collagen mRNAs; these effects lagged significantly behind the elevation of alkaline phosphatase and type X collagen. Addition of beta-glycerophosphate to the medium increased calcium deposition in the presence of ascorbate but had no effect on levels of collagen mRNAs or alkaline phosphatase. The results suggest that vitamin C may play an important role in endochondral bone formation by modulating gene expression in hypertrophic chondrocytes.

Alkaline Earth Core Level Photoemission Spectroscopy of High-Temperature Superconductors

NASA Technical Reports Server (NTRS)

Vasquez, R.

1993-01-01

This paper examines photoemission measurements of the alkaline Earth core levels of high-temperature superconductors and related materials, models that seek to explain the large negative shifts observed relative to the corresponding alkaline Earth metals, and the effect of lattice site disorder on the core level spectra and the presence or absence of intrinsic surface peaks.

Comprehensive investigations of kinetics of alkaline hydrolysis of TNT (2,4,6-trinitrotoluene), DNT (2,4-dinitrotoluene), and DNAN (2,4-dinitroanisole).

PubMed

Sviatenko, Liudmyla; Kinney, Chad; Gorb, Leonid; Hill, Frances C; Bednar, Anthony J; Okovytyy, Sergiy; Leszczynski, Jerzy

2014-09-02

Combined experimental and computational techniques were used to analyze multistep chemical reactions in the alkaline hydrolysis of three nitroaromatic compounds: 2,4,6-trinitrotoluene (TNT), 2,4-dinitrotoluene (DNT), and 2,4-dinitroanisole (DNAN). The study reveals common features and differences in the kinetic behavior of these compounds. The analysis of the predicted pathways includes modeling of the reactions, along with simulation of UV-vis spectra, experimental monitoring of reactions using LC/MS techniques, development of the kinetic model by designing and solving the system of differential equations, and obtaining computationally predicted kinetics for decay and accumulation of reactants and products. Obtained results suggest that DNT and DNAN are more resistant to alkaline hydrolysis than TNT. The direct substitution of a nitro group by a hydroxide represents the most favorable pathway for all considered compounds. The formation of Meisenheimer complexes leads to the kinetic first-step intermediates in the hydrolysis of TNT. Janovsky complexes can also be formed during hydrolysis of TNT and DNT but in small quantities. Methyl group abstraction is one of the suggested pathways of DNAN transformation during alkaline hydrolysis.

Reductive atmospheric acid leaching of spent alkaline batteries in H2SO4/Na2SO3 solutions

NASA Astrophysics Data System (ADS)

Morcali, Mehmet Hakan

2015-07-01

This work studies the optimum reductive leaching process for manganese and zinc recovery from spent alkaline battery paste. The effects of reducing agents, acid concentration, pulp density, reaction temperature, and leaching time on the dissolution of manganese and zinc were investigated in detail. Manganese dissolution by reductive acidic media is an intermediate-controlled process with an activation energy of 12.28 kJ·mol-1. After being leached, manganese and zinc were selectively precipitated with sodium hydroxide. The zinc was entirely converted into zincate (Zn(OH){4/2-}) ions and thus did not co-precipitate with manganese hydroxide during this treatment (2.0 M NaOH, 90 min, 200 r/min, pH > 13). After the manganese was removed from the solution, the Zn(OH){4/2-} was precipitated as zinc sulfate in the presence of sulfuric acid. The results indicated that this process could be effective in recovering manganese and zinc from alkaline batteries.

Electrocatalysis of the HER in acid and alkaline media

DOE PAGES

Danilovic, Nemanja; Subbaraman, Ram; Strmcnik, Dusan; ...

2013-01-01

Trends in the HER are studied on selected metals (M= Cu, Ag, Au, Pt, Ru, Ir, Ti) in acid and alkaline environments. Here, we found that with the exception of Pt, Ir and Au, due to high coverage by spectator species on non-noble metal catalysts, experimentally established positions of Cu , Ag, Ru and Ti in the observed volcano relations are still uncertain. We also found that while in acidic solutions the M-Hupd binding energy most likely is controlling the activity trends, the trends in activity in alkaline solutions are controlled by a delicate balance between two descriptors: the M-Hadmore » interaction as well as the energetics required to dissociate water molecules. We confirm the importance of the second descriptor by introducing bifunctional catalysts such as M modified by Ni(OH); e.g. while the latter serves to enhance catalytic decomposition of water, the metal sites are required for collecting and recombining the produced hydrogen intermediates.« less

Enhancement of the reduction efficiency of soluble starch for platinum nanoparticles synthesis.

PubMed

Tongsakul, Duangta; Wongravee, Kanet; Thammacharoen, Chuchaat; Ekgasit, Sanong

2012-08-01

In this work, the efficiency of soluble starch as a reducing and a stabilizing agent in the synthesis of platinum nanoparticles under acidic-alkaline treatment is systematically studied. The degraded intermediates with reducing potential (i.e., small molecules containing aldehyde and α-hydroxy ketone moieties) are concomitantly generated when the alkaline concentration is greater than 0.025 M. The in situ generated species could completely reduce platinum ions (20 mM) and sufficiently stabilize the obtained platinum nanoparticles (5 mM) of uniform particle size (2-4 nm). The reduction is efficient and rapid as a complete conversion is achieved within 5 min. In a stronger alkaline condition, the platinum nanoparticles tend to aggregate and form a bigger domain because extensive degradation generates small starch fragments with less stabilization efficiency. This observation suggests that starch is a promising green material which could be chemically treated and transformed to a powerful reducing agent and stabilizer for the synthesis of metal nanoparticles. Copyright © 2012 Elsevier Ltd. All rights reserved.

Oxidation of L-phenylalanine by diperiodatoargentate(III) in aqueous alkaline medium. A Mechanistic approach

NASA Astrophysics Data System (ADS)

Lamani, S. D.; Veeresh, T. M.; Nandibewoor, S. T.

2009-12-01

The kinetics of oxidation of L-phenylalanine (L-Phe) by diperiodatoargentate(III) (DPA) in alkaline medium at a constant ionic strength of 0.25 mol/dm-3 has been studied spectrophotometrically. The reaction between DPA and L-phenylalanine in alkaline medium exhibits 1: 1 stoichiometry (L-phenylalanine: DPA). The reaction shows first order in [DPA] and has less than unit order dependence each in both [L-Phe] and [Alkali] and retarding effect of [IO{4/-}] under the reaction conditions. The active species of DPA is understood to be as monoperiodatoargentate(III) (MPA). The reaction is shown to proceed via a MPA-L-Phe complex, which decomposes in a rate-determining step to give intermediates followed by a fast step to give the products. The products were identified by spot and spectroscopic studies. The reaction constants involved in the different steps of the mechanisms were calculated. The activation parameters with respect to slow step of the mechanism were computed and discussed. The thermodynamic quantities were also determined for the reaction.

Instability mechanisms and early warning indicators for mesophilic anaerobic digestion of vegetable waste.

PubMed

Li, Dong; Chen, Lin; Liu, Xiaofeng; Mei, Zili; Ren, Haiwei; Cao, Qin; Yan, Zhiying

2017-12-01

In order to elucidate the instability mechanism, screen early warning indicators, and propose control measures, the mesophilic digestion of vegetable waste (VW) was carried out at organic loading rates (OLR) of 0.5, 1.0, and 1.5g volatile solid (VS)/(Ld). The process parameters, including biogas components, volatile fatty acids (VFA), ammonia, pH, total alkalinity (TA), bicarbonate alkalinity (BA), and intermediate alkalinity (IA), were monitored every day. Digestion was inhibited at OLR of 1.5gVS/(Ld). The primary causes of instability are a high sugar and negligible ammonia content, in addition to the feed without effluent recirculation, which led to BA loss. The ratios of CH 4 /CO 2 , VFA/BA, propionate, n-butyrate and iso-valerate were selected as early warning indicators. In order to maintain the digestion of VW at a high OLR, control measures including effluent recirculation and trace element addition are recommended. Copyright © 2017 Elsevier Ltd. All rights reserved.

Characterization of wheat straw-degrading anaerobic alkali-tolerant mixed cultures from soda lake sediments by molecular and cultivation techniques

PubMed Central

Porsch, Katharina; Wirth, Balázs; Tóth, Erika M; Schattenberg, Florian; Nikolausz, Marcell

2015-01-01

Alkaline pretreatment has the potential to enhance the anaerobic digestion of lignocellulosic biomass to biogas. However, the elevated pH of the substrate may require alkalitolerant microbial communities for an effective digestion. Three mixed anaerobic lignocellulolytic cultures were enriched from sediments from two soda lakes with wheat straw as substrate under alkaline (pH 9) mesophilic (37°C) and thermophilic (55°C) conditions. The gas production of the three cultures ceased after 4 to 5 weeks, and the produced gas was composed of carbon dioxide and methane. The main liquid intermediates were acetate and propionate. The physiological behavior of the cultures was stable even after several transfers. The enrichment process was also followed by molecular fingerprinting (terminal restriction fragment length polymorphism) of the bacterial 16S rRNA gene and of the mcrA/mrtA functional gene for methanogens. The main shift in the microbial community composition occurred between the sediment samples and the first enrichment, whereas the structure was stable in the following transfers. The bacterial communities mainly consisted of Sphingobacteriales, Clostridiales and Spirochaeta, but differed at genus level. Methanothermobacter and Methanosarcina genera and the order Methanomicrobiales were predominant methanogenes in the obtained cultures. Additionally, single cellulolytic microorganisms were isolated from enrichment cultures and identified as members of the alkaliphilic or alkalitolerant genera. The results show that anaerobic alkaline habitats harbor diverse microbial communities, which can degrade lignocellulose effectively and are therefore a potential resource for improving anaerobic digestion. PMID:25737100

Insights into the evolution of an alkaline magmatic system: An in situ trace element study of clinopyroxenes from the Ditrău Alkaline Massif, Romania

NASA Astrophysics Data System (ADS)

Batki, Anikó; Pál-Molnár, Elemér; Jankovics, M. Éva; Kerr, Andrew C.; Kiss, Balázs; Markl, Gregor; Heincz, Adrián; Harangi, Szabolcs

2018-02-01

Clinopyroxene is a major constituent in most igneous rock types (hornblendite, diorite, syenite, nepheline syenite, camptonite, tinguaite and ijolite) of the Ditrău Alkaline Massif, Eastern Carpathians, Romania. Phenocryst and antecryst populations have been distinguished based on mineral zoning patterns and geochemical characteristics. Major and trace element compositions of clinopyroxenes reflect three dominant pyroxene types including primitive high-Cr Fe-diopside, intermediate Na-diopside-hedenbergite and evolved high-Zr aegirine-augite. Clinopyroxenes record two major magma sources as well as distinct magma evolution trends. The primitive diopside population is derived from an early camptonitic magma related to basanitic parental melts, whilst the intermediate diopside-hedenbergite crystals represent a Na-, Nb- and Zr-rich magma source recognised for the first time in the Ditrău magmatic system. This magma fractionated towards ijolitic and later phonolitic compositions. Field observations, petrography and clinopyroxene-melt equilibrium calculations reveal magma recharge and mingling, pyroxene recycling, fractional crystallisation and accumulation. Repeated recharge events of the two principal magmas resulted in multiple interactions between more primitive and more fractionated co-existing magma batches. Magma mingling occurred between mafic and felsic magmas by injection of ijolitic magma into fissures (dykes) containing phonolitic (tinguaite) magma. This study shows that antecryst recycling, also described for the first time in Ditrău, is a significant process during magma recharge and demonstrates that incorporated crystals can crucially affect the host magma composition and so whole-rock chemical data should be interpreted with great care.

Electro-oxidation of methanol on gold in alkaline media: Adsorption characteristics of reaction intermediates studied using time resolved electro-chemical impedance and surface plasmon resonance techniques

NASA Astrophysics Data System (ADS)

Assiongbon, K. A.; Roy, D.

2005-12-01

Electro-catalytic oxidation of methanol is the anode reaction in direct methanol fuel cells. We have studied the adsorption characteristics of the intermediate reactants of this multistep reaction on a gold film electrode in alkaline solutions by combining surface plasmon resonance (SPR) measurements with Fourier transform electro-chemical impedance spectroscopy (FT-EIS). Methanol oxidation in this system shows no significant effects of "site poisoning" by chemisorbed CO. Our results suggest that OH - chemisorbed onto Au acts as a stabilizing agent for the surface species of electro-active methanol. Double layer charging/discharging and adsorption/desorption of OH - show more pronounced effects than adsorption/oxidation of methanol in controlling the surface charge density of the Au substrate. These effects are manifested in both the EIS and the SPR data, and serve as key indicators of the surface reaction kinetics. The data presented here describe the important role of adsorbed OH - in electro-catalysis of methanol on Au, and demonstrate how SPR and FT-EIS can be combined for quantitative probing of catalytically active metal-solution interfaces.

Incidence of vitamin D deficiency rickets among Australian children: an Australian Paediatric Surveillance Unit study.

PubMed

Munns, Craig F; Simm, Peter J; Rodda, Christine P; Garnett, Sarah P; Zacharin, Margaret R; Ward, Leanne M; Geddes, Janet; Cherian, Sarah; Zurynski, Yvonne; Cowell, Christopher T

2012-04-16

To determine the incidence of and factors associated with vitamin D deficiency rickets in Australian children. 18-month questionnaire-based prospective observational study, using Australian Paediatric Surveillance Unit (APSU) data. Australian paediatricians and child health workers, January 2006 - July 2007. Children aged ≤ 15 years with vitamin D deficiency rickets (25-hydroxyvitamin D [25OHD] ≤ 50 nmol/L, and elevated alkaline phosphatase levels [> 229 IU/L] and/or radiological rickets). Incidence of vitamin D deficiency rickets. Description of demographics, clinical presentation, identification and further analysis of overrepresented groups, and treatment regimens compared with best-practice guidelines. We identified 398 children with vitamin D deficiency (55% male; median age, 6.3 years [range, 0.2-15 years]). The overall incidence in children ≤ 15 years of age in Australia was 4.9/100 000/year. All had a low 25OHD level (median, 28 nmol/L [range, 5-50 nmol]) and an elevated alkaline phosphatase level (median, 407 IU/L [range, 229-5443 IU/L]), and 48 (12%) were hypocalcaemic. Ninety-five children had wrist x-rays, of whom 67 (71%) had rachitic changes. Most (98%) had dark or intermediate skin colour and 18% of girls were partially or completely veiled. Most children were born in Africa (252; 63%) and 75% of children were refugees. Duration of exclusive breastfeeding was inversely related to serum vitamin D levels in children < 3 years of age. Empirical vitamin D treatment was given to 4% of children before diagnosis. Vitamin D deficiency rickets is a significant problem in Australia among known high-risk groups. Public health campaigns to prevent, identify and tre@vitamin D deficiency, especially in high-risk groups, are essential.

Identification of succinimide sites in proteins by N-terminal sequence analysis after alkaline hydroxylamine cleavage.

PubMed Central

Kwong, M. Y.; Harris, R. J.

1994-01-01

Under favorable conditions, Asp or Asn residues can undergo rearrangement to a succinimide (cyclic imide), which may also serve as an intermediate for deamidation and/or isoaspartate formation. Direct identification of such succinimides by peptide mapping is hampered by their lability at neutral and alkaline pH. We determined that incubation in 2 M hydroxylamine, 0.2 M Tris buffer, pH 9, for 2 h at 45 degrees C will specifically cleave on the C-terminal side of succinimides without cleavage at Asn-Gly bonds; yields are typically approximately 50%. N-terminal sequence analysis can then be used to identify an internal sequence generated by cleavage of the succinimide, hence identifying the succinimide site. PMID:8142891

Sodic alkaline stress mitigation by exogenous melatonin in tomato needs nitric oxide as a downstream signal.

PubMed

Liu, Na; Gong, Biao; Jin, Zhiyong; Wang, Xiufeng; Wei, Min; Yang, Fengjuan; Li, Yan; Shi, Qinghua

2015-08-15

The present study was designed to determine the interactive effect of exogenous melatonin and nitric oxide (NO) on sodic alkaline stress mitigation in tomato seedlings. It was observed that exogenous melatonin treatment elevated NO levels in alkaline-stressed tomato roots. However, exogenous NO had little effects on melatonin levels. Importantly, melatonin-induced NO generation was accompanied by increased tolerance to alkaline stress. Chemical scavenging of NO reduced melatonin-induced alkaline stress tolerance and defense genes' expression. However, inhibition of melatonin biosynthesis had a little effect on NO-induced alkaline stress tolerance. These results strongly suggest that NO, acting as a downstream signal, is involved in the melatonin-induced tomato tolerance to alkaline stress. This process creates a new signaling pathway for improving stress tolerance in plant. Copyright © 2015 Elsevier GmbH. All rights reserved.

Aleutian tholeiitic and calc-alkaline magma series I: The mafic phenocrysts

NASA Astrophysics Data System (ADS)

Kay, S. Mahlburg; Kay, Robert W.

1985-07-01

Diagnostic mafic silicate assemblages in a continuous spectrum of Aleutian volcanic rocks provide evidence for contrasts in magmatic processes in the Aleutian arc crust. Tectonic segmentation of the arc exerts a primary control on the variable mixing, fractional crystallization and possible assimilation undergone by the magmas. End members of the continuum are termed calc-alkaline (CA) and tholeiitic (TH). CA volcanic rocks (e.g., Buldir and Moffett volcanoes) have low FeO/MgO ratios and contain compositionally diverse phenocryst populations, indicating magma mixing. Their Ni and Cr-rich magnesian olivine and clinopyroxene come from mantle-derived mafic olivine basalts that have mixed with more fractionated magmas at mid-to lower-crustal levels immediately preceding eruption. High-Al amphibole is associated with the mafic end member. In contrast, TH lavas (e.g., Okmok and Westdahl volcanoes) have high FeO/MgO ratios and contain little evidence for mixing. Evolved lavas represent advanced stages of low pressure crystallization from a basaltic magma. These lavas contain groundmass olivine (FO 40 50) and lack Ca-poor pyroxene. Aleutian volcanic rocks with intermediate FeO/MgO ratios are termed transitional tholeiitic (TTH) and calc-alkaline (TCA). TCA magmas are common (e.g., Moffett, Adagdak, Great Sitkin, and Kasatochi volcanoes) and have resulted from mixing of high-Al basalt with more evolved magmas. They contain amphibole (high and low-Al) or orthopyroxene or both and are similar to the Japanese hypersthene-series. TTH magmas (e.g., Okmok and Westdahl) contain orthopyroxene or pigeonite or both, and show some indication of upper crustal mixing. They are mineralogically similar to the Japanese pigeonite-series. High-Al basalt lacks Mg-rich mafic phases and is a derivative magma produced by high pressure fractionation of an olivine tholeiite. The low pressure mineral assemblage of high-Al basalt results from crystallization at higher crustal levels.

Pre-operative serum alkaline phosphatase as a predictive indicator of post-operative hypocalcaemia in patients undergoing total thyroidectomy.

PubMed

Miah, M S; Mahendran, S; Mak, C; Leese, G; Smith, D

2015-11-01

This study aimed to evaluate whether a pre-operative elevated serum alkaline phosphatase level is a potential predictor of post-operative hypocalcaemia after total thyroidectomy. Data was retrospectively collected from the case notes of patients who had undergone total thyroidectomy. Patients were divided into Graves' disease and non-Graves' groups. Pre-operative and post-operative biochemical markers, including serum calcium, alkaline phosphatase and parathyroid hormone levels, were reviewed. A total of 225 patients met the inclusion criteria. Graves' disease was the most common indication (n = 134; 59.5 per cent) for thyroidectomy. Post-operative hypocalcaemia developed in 48 patients (21.3 per cent) and raised pre-operative serum alkaline phosphatase was noted in 94 patients (41.8 per cent). Raised pre-operative serum alkaline phosphatase was significantly associated with post-operative hypocalcaemia, particularly in Graves' disease patients (p < 0.05). Pre-operative serum alkaline phosphatase measurements help to predict post-thyroidectomy hypocalcaemia, especially in patients who do not develop hypoparathyroidism. Ascertaining the pre-operative serum alkaline phosphatase level in patients undergoing total thyroidectomy may help surgeons to identify at-risk patients.

Elevated serum level of human alkaline phosphatase in obesity.

PubMed

Khan, Abdul Rehman; Awan, Fazli Rabbi; Najam, Syeda Sadia; Islam, Mehboob; Siddique, Tehmina; Zain, Maryam

2015-11-01

To investigate a correlation between serum alkaline phosphatase level and body mass index in human subjects. The comparative cross-sectional study was carried out at the National Institute for Biotechnology and Genetic Engineering, Faisalabad, Pakistan, from April 2012 to June 2013. Blood serum alkaline phosphatase levels were estimated and the subjects were divided into three sub-groups on the basis of their body mass. normal weight (<25kg/m2), overweight (25-27kg/m2) and obese (>27kg/m2) subjects. The serum samples were used for the estimation of clinically important biochemical parameters, using commercial kits on clinical chemistry analyser. Of the 197 subjects, 97(49%) were obese and 100(51%) were non-obese. The serum alkaline phosphatase level increased in obese (214±6.4 IU/L) compared to the non-obese subjects (184.5±5 IU/L). Furthermore, a significant linear relationship (r=0.3;p-0.0001) was found between serum alkaline phosphatase and body mass index. Other biochemical variables were not correlated to the body mass index. Over activity and higher amounts of alkaline phosphatase were linked to the development of obesity.

Salivary Alkaline Phosphatase as a Noninvasive Marker for Periodontal Disease in Children with Uncontrolled Type 1 Diabetes Mellitus.

PubMed

Sridharan, Srirangarajan; Sravani, Paruchuri; Satyanarayan, Aparna; Kiran, K; Shetty, Varun

The aim of this pilot study was to determine whether salivary alkaline phosphatase levels can be a non invasive marker for early inflammatory periodontal disease in children with uncontrolled type 1 diabetes mellitus. 10 healthy children (group 1), 10 children with recently diagnosed type 1 diabetes mellitus (group 2) and 10 children with type 1 diabetes mellitus for more than 4 years (group 3) were recruited for the study. All three groups were matched for age, gender and socioeconomic status. Periodontal health was assessed by plaque index, gingival index and probing pocket depth. Metabolic status was assessed by glycosylated hemoglobin levels, salivary alkaline phosphatase levels were determined by spectrophotometer. Data was analyzed by Kruskal Wallis ANOVA, Mann-Whitney U test and Spearman's rank correlation method. Salivary alkaline phosphatase levels correlated significantly with the periodontal parameters in the diabetic group. An increase in salivary alkaline phosphatase levels increased with increased values of gingival index and probing pocket depth. Group 3 showed greater correlation than group 2 and group 1. At p value p<0.05. The glycemic status of the children affects the periodontal disease parameters. Salivary alkaline phosphatase levels could be a useful tool in analyzing periodontal status of children with uncontrolled type I diabetes mellitus.

De Novo Transcriptional Analysis of Alfalfa in Response to Saline-Alkaline Stress.

PubMed

An, Yi-Min; Song, Li-Li; Liu, Ying-Rui; Shu, Yong-Jun; Guo, Chang-Hong

2016-01-01

Saline-alkaline stress, caused by high levels of harmful carbonate salts and high soil pH, is a major abiotic stress that affects crop productivity. Alfalfa is a widely cultivated perennial forage legume with some tolerance to biotic and abiotic stresses, especially to saline-alkaline stress. To elucidate the mechanism underlying plant saline-alkaline tolerance, we conducted transcriptome analysis of whole alfalfa seedlings treated with saline-alkaline solutions for 0 day (control), 1 day (short-term treatment), and 7 days (long-term treatment) using ion torrent sequencing technology. A transcriptome database dataset of 53,853 unigenes was generated, and 2,286 and 2,233 genes were differentially expressed in the short-term and long-term treatment, respectively. Gene ontology analysis revealed 14 highly enriched pathways and demonstrated the differential response of metabolic pathways between the short-term and long-term treatment. The expression levels of 109 and 96 transcription factors were significantly altered significantly after 1 day and 7 days of treatment, respectively. Specific responses of peroxidase, flavonoids, and the light pathway component indicated that the antioxidant capacity was one of the central mechanisms of saline-alkaline stress tolerance response in alfalfa. Among the 18 differentially expressed genes examined by real time PCR, the expression levels of eight genes, including inositol transporter, DNA binding protein, raffinose synthase, ferritin, aldo/keto reductase, glutathione S-transferase, xyloglucan endotrans glucosylase, and a NAC transcription factor, exhibited different patterns in response to saline and alkaline stress. The expression levels of the NAC transcription factor and glutathione S-transferase were altered significantly under saline stress and saline-alkaline stress; they were upregulated under saline-alkaline stress and downregulated under salt stress. Physiology assays showed an increased concentration of reactive oxygen species and malondialdehyde and a decreased content of chlorophyll, indicating that anti-oxidation and detoxification play an important role in response to saline-alkaline stress. Overall, the transcriptome analysis provided novel insights into the saline-alkaline stress tolerance response mechanisms in alfalfa.

De Novo Transcriptional Analysis of Alfalfa in Response to Saline-Alkaline Stress

PubMed Central

An, Yi-Min; Song, Li-Li; Liu, Ying-Rui; Shu, Yong-Jun; Guo, Chang-Hong

2016-01-01

Saline-alkaline stress, caused by high levels of harmful carbonate salts and high soil pH, is a major abiotic stress that affects crop productivity. Alfalfa is a widely cultivated perennial forage legume with some tolerance to biotic and abiotic stresses, especially to saline-alkaline stress. To elucidate the mechanism underlying plant saline-alkaline tolerance, we conducted transcriptome analysis of whole alfalfa seedlings treated with saline-alkaline solutions for 0 day (control), 1 day (short-term treatment), and 7 days (long-term treatment) using ion torrent sequencing technology. A transcriptome database dataset of 53,853 unigenes was generated, and 2,286 and 2,233 genes were differentially expressed in the short-term and long-term treatment, respectively. Gene ontology analysis revealed 14 highly enriched pathways and demonstrated the differential response of metabolic pathways between the short-term and long-term treatment. The expression levels of 109 and 96 transcription factors were significantly altered significantly after 1 day and 7 days of treatment, respectively. Specific responses of peroxidase, flavonoids, and the light pathway component indicated that the antioxidant capacity was one of the central mechanisms of saline-alkaline stress tolerance response in alfalfa. Among the 18 differentially expressed genes examined by real time PCR, the expression levels of eight genes, including inositol transporter, DNA binding protein, raffinose synthase, ferritin, aldo/keto reductase, glutathione S-transferase, xyloglucan endotrans glucosylase, and a NAC transcription factor, exhibited different patterns in response to saline and alkaline stress. The expression levels of the NAC transcription factor and glutathione S-transferase were altered significantly under saline stress and saline-alkaline stress; they were upregulated under saline-alkaline stress and downregulated under salt stress. Physiology assays showed an increased concentration of reactive oxygen species and malondialdehyde and a decreased content of chlorophyll, indicating that anti-oxidation and detoxification play an important role in response to saline-alkaline stress. Overall, the transcriptome analysis provided novel insights into the saline-alkaline stress tolerance response mechanisms in alfalfa. PMID:27458463

High Electrocatalytic Hydrogen Evolution Activity of an Anomalous Ruthenium Catalyst.

PubMed

Zheng, Yao; Jiao, Yan; Zhu, Yihan; Li, Lu Hua; Han, Yu; Chen, Ying; Jaroniec, Mietek; Qiao, Shi-Zhang

2016-12-14

Hydrogen evolution reaction (HER) is a critical process due to its fundamental role in electrocatalysis. Practically, the development of high-performance electrocatalysts for HER in alkaline media is of great importance for the conversion of renewable energy to hydrogen fuel via photoelectrochemical water splitting. However, both mechanistic exploration and materials development for HER under alkaline conditions are very limited. Precious Pt metal, which still serves as the state-of-the-art catalyst for HER, is unable to guarantee a sustainable hydrogen supply. Here we report an anomalously structured Ru catalyst that shows 2.5 times higher hydrogen generation rate than Pt and is among the most active HER electrocatalysts yet reported in alkaline solutions. The identification of new face-centered cubic crystallographic structure of Ru nanoparticles was investigated by high-resolution transmission electron microscopy imaging, and its formation mechanism was revealed by spectroscopic characterization and theoretical analysis. For the first time, it is found that the Ru nanocatalyst showed a pronounced effect of the crystal structure on the electrocatalytic activity tested under different conditions. The combination of electrochemical reaction rate measurements and density functional theory computation shows that the high activity of anomalous Ru catalyst in alkaline solution originates from its suitable adsorption energies to some key reaction intermediates and reaction kinetics in the HER process.

VSL#3 probiotic upregulates intestinal mucosal alkaline sphingomyelinase and reduces inflammation.

PubMed

Soo, I; Madsen, K L; Tejpar, Q; Sydora, B C; Sherbaniuk, R; Cinque, B; Di Marzio, L; Cifone, M Grazia; Desimone, C; Fedorak, R N

2008-03-01

Alkaline sphingomyelinase, an enzyme found exclusively in bile and the intestinal brush border, hydrolyzes sphingomyelin into ceramide, sphingosine and sphingosine-1-phosphate, thereby inducing epithelial apoptosis. Reduced levels of alkaline sphingomyelinase have been found in premalignant and malignant intestinal epithelia and in ulcerative colitis tissue. Probiotic bacteria can be a source of sphingomyelinase. To determine the effect of VSL#3 probiotic therapy on mucosal levels of alkaline sphingomyelinase, both in a mouse model of colitis and in patients with ulcerative colitis. Interleukin-10 gene-deficient (IL10KO) and wild type control mice were treated with VSL#3 (10(9) colony-forming units per day) for three weeks, after which alkaline sphingomyelinase activity was measured in ileal and colonic tissue. As well, 15 patients with ulcerative colitis were treated with VSL#3 (900 billion bacteria two times per day for five weeks). Alkaline sphingomyelinase activity was measured through biopsies and comparison of ulcerative colitis disease activity index scores obtained before and after treatment. Lowered alkaline sphingomyelinase levels were seen in the colon (P=0.02) and ileum (P=0.04) of IL10KO mice, as compared with controls. Treatment of these mice with VSL#3 resulted in upregulation of mucosal alkaline sphingomyelinase activity in both the colon (P=0.04) and the ileum (P=0.01). VSL#3 treatment of human patients who had ulcerative colitis decreased mean (+/- SEM) ulcerative colitis disease activity index scores from 5.3+/-1.8946 to 0.70+/-0.34 (P=0.02) and increased mucosal alkaline sphingomyelinase activity. Mucosal alkaline sphingomyelinase activity is reduced in the intestine of IL10KO mice with colitis and in humans with ulcerative colitis. VSL#3 probiotic therapy upregulates mucosal alkaline sphingomyelinase activity.

HPLC and HPLC/MS/MS Studies on Stress, Accelerated and Intermediate Degradation Tests of Antivirally Active Tricyclic Analog of Acyclovir.

PubMed

Lesniewska, Monika A; Dereziński, Paweł; Klupczyńska, Agnieszka; Kokot, Zenon J; Ostrowski, Tomasz; Zeidler, Joanna; Muszalska, Izabela

2015-01-01

The degradation behavior of a tricyclic analog of acyclovir [6-(4-MeOPh)-TACV] was determined in accordance with International Conference on Harmonization guidelines for good clinical practice under different stress conditions (neutral hydrolysis, strong acid/base degradation, oxidative decomposition, photodegradation, and thermal degradation). Accelerated [40±2°C/75%±5% relative humidity (RH)] and intermediate (30±2°C/65%±5% RH) stability tests were also performed. For observation of the degradation of the tested compound the RP-HPLC was used, whereas for the analysis of its degradation products HPLC/MS/MS was used. Degradation of the tested substance allowed its classification as unstable in neutral environment, acidic/alkaline medium, and in the presence of oxidizing agent. The tested compound was also light sensitive and was classified as photolabile both in solution and in the solid phase. However, the observed photodegradation in the solid phase was at a much lower level than in the case of photodegradation in solution. The study showed that both air temperature and RH had no significant effect on the stability of the tested substance during storage for 1 month at 100°C (dry heat) as well as during accelerated and intermediate tests. Based on the HPLC/MS/MS analysis, it can be concluded that acyclovir was formed as a degradation product of 6-(4-MeOPh)-TACV.

Could artificial ocean alkalinization protect tropical coral ecosystems from ocean acidification?

NASA Astrophysics Data System (ADS)

Feng, Ellias Y.; Keller, David P.; Koeve, Wolfgang; Oschlies, Andreas

2016-07-01

Artificial ocean alkalinization (AOA) is investigated as a method to mitigate local ocean acidification and protect tropical coral ecosystems during a 21st century high CO2 emission scenario. Employing an Earth system model of intermediate complexity, our implementation of AOA in the Great Barrier Reef, Caribbean Sea and South China Sea regions, shows that alkalinization has the potential to counteract expected 21st century local acidification in regard to both oceanic surface aragonite saturation Ω and surface pCO2. Beyond preventing local acidification, regional AOA, however, results in locally elevated aragonite oversaturation and pCO2 decline. A notable consequence of stopping regional AOA is a rapid shift back to the acidified conditions of the target regions. We conclude that AOA may be a method that could help to keep regional coral ecosystems within saturation states and pCO2 values close to present-day values even in a high-emission scenario and thereby might ‘buy some time’ against the ocean acidification threat, even though regional AOA does not significantly mitigate the warming threat.

Atomic hydrogen in. gamma. -irradiated hydroxides of alkaline-earth elements

DOE Office of Scientific and Technical Information (OSTI.GOV)

Spitsyn, V.I.; Yurik, T.K.; Barsova, L.I.

1982-04-01

Atomic hydrogen is an important intermediate product formed in the radiolysis of compounds containing X-H bonds. H atoms have been detected in irradiated matrices of H/sub 2/ and inert gases at 4/sup 0/K, in irradiated ice and frozen solutions of acids in irradiated salts and in other systems. Here results are presented from a study of the ESR spectra of H atoms generated in polycrystalline hydroxides of alkaline-earth elements that have been ..gamma..-irradiated at 77/sup 0/K, after preliminary treatment at various temperatures. For the first time stabilization of atomic hydrogen in ..gamma..-irradiated polycrystalline alkaline-earth element hydroxides has been detected. Dependingmore » on the degree of dehydroxylation, several types of hydrogen atoms may be stabilized in the hydroxides, these hydrogen atoms having different radiospectroscopic parameters. In the magnesium-calcium-strontium-barium hydroxide series, a regular decrease has been found in the hfi constants for H atoms with the cations in the immediate surroundings. A direct proportionality has been found between the parameters ..delta..A/A/sub 0/ and the polarizability of the cation.« less

The Alkaline Hydrolysis of Sulfonate Esters: Challenges in Interpreting Experimental and Theoretical Data

PubMed Central

2013-01-01

Sulfonate ester hydrolysis has been the subject of recent debate, with experimental evidence interpreted in terms of both stepwise and concerted mechanisms. In particular, a recent study of the alkaline hydrolysis of a series of benzene arylsulfonates (Babtie et al., Org. Biomol. Chem.10, 2012, 8095) presented a nonlinear Brønsted plot, which was explained in terms of a change from a stepwise mechanism involving a pentavalent intermediate for poorer leaving groups to a fully concerted mechanism for good leaving groups and supported by a theoretical study. In the present work, we have performed a detailed computational study of the hydrolysis of these compounds and find no computational evidence for a thermodynamically stable intermediate for any of these compounds. Additionally, we have extended the experimental data to include pyridine-3-yl benzene sulfonate and its N-oxide and N-methylpyridinium derivatives. Inclusion of these compounds converts the Brønsted plot to a moderately scattered but linear correlation and gives a very good Hammett correlation. These data suggest a concerted pathway for this reaction that proceeds via an early transition state with little bond cleavage to the leaving group, highlighting the care that needs to be taken with the interpretation of experimental and especially theoretical data. PMID:24279349

Ethylene Inhibits Root Elongation during Alkaline Stress through AUXIN1 and Associated Changes in Auxin Accumulation1

PubMed Central

Li, Juan; Xu, Heng-Hao; Liu, Wen-Cheng; Zhang, Xiao-Wei

2015-01-01

Soil alkalinity causes major reductions in yield and quality of crops worldwide. The plant root is the first organ sensing soil alkalinity, which results in shorter primary roots. However, the mechanism underlying alkaline stress-mediated inhibition of root elongation remains to be further elucidated. Here, we report that alkaline conditions inhibit primary root elongation of Arabidopsis (Arabidopsis thaliana) seedlings by reducing cell division potential in the meristem zones and that ethylene signaling affects this process. The ethylene perception antagonist silver (Ag+) alleviated the inhibition of root elongation by alkaline stress. Moreover, the ethylene signaling mutants ethylene response1-3 (etr1-3), ethylene insensitive2 (ein2), and ein3-1 showed less reduction in root length under alkaline conditions, indicating a reduced sensitivity to alkalinity. Ethylene biosynthesis also was found to play a role in alkaline stress-mediated root inhibition; the ethylene overproducer1-1 mutant, which overproduces ethylene because of increased stability of 1-AMINOCYCLOPROPANE-1-CARBOXYLIC ACID SYNTHASE5, was hypersensitive to alkaline stress. In addition, the ethylene biosynthesis inhibitor cobalt (Co2+) suppressed alkaline stress-mediated inhibition of root elongation. We further found that alkaline stress caused an increase in auxin levels by promoting expression of auxin biosynthesis-related genes, but the increase in auxin levels was reduced in the roots of the etr1-3 and ein3-1 mutants and in Ag+/Co2+-treated wild-type plants. Additional genetic and physiological data showed that AUXIN1 (AUX1) was involved in alkaline stress-mediated inhibition of root elongation. Taken together, our results reveal that ethylene modulates alkaline stress-mediated inhibition of root growth by increasing auxin accumulation by stimulating the expression of AUX1 and auxin biosynthesis-related genes. PMID:26109425

Increase in serum alkaline phosphatase due to fatty meal in undergraduate students of Khyber Medical University, Khyber Pakhtunkhwa.

PubMed

Khan, Muhammad Jaseem; Ahmed, Basir; Ahmed, Saeed; Khan, Momin

2016-04-01

To evaluate the effect of fatty meal on intestinal alkaline phosphatase. The cross-sectional study was conducted at Khyber Medical University, Peshawar, Pakistan from March to April 2014 and comprised young healthy individuals 18-25 years of age. Whole blood samples were collected from the subjects in ethylenediaminetetraacetic acid anti-coagulated and plane serum tubes. For blood group analysis, blood group anti sera were used, while for serum alkaline phosphatase, a chemistry analyser was used. Alkaline phosphatase levels in the blood before and after breakfast were compared. Of the 177 subjects, there were 139(78.5%) men and 38(21.4%) women. Mean fasting alkaline phosphatise level was 144.22+/-75.57, while mean random value was 174.15+/-96.70 (p=0.001). Serum alkaline phosphatise must be analysed in fasting state early in the morning.

Replicative Intermediates of Human Papillomavirus Type 11 in Laryngeal Papillomas: Site of Replication Initiation and Direction of Replication

NASA Astrophysics Data System (ADS)

Auborn, K. J.; Little, R. D.; Platt, T. H. K.; Vaccariello, M. A.; Schildkraut, C. L.

1994-07-01

We have examined the structures of replication intermediates from the human papillomavirus type 11 genome in DNA extracted from papilloma lesions (laryngeal papillomas). The sites of replication initiation and termination utilized in vivo were mapped by using neutral/neutral and neutral/alkaline two-dimensional agarose gel electrophoresis methods. Initiation of replication was detected in or very close to the upstream regulatory region (URR; the noncoding, regulatory sequences upstream of the open reading frames in the papillomavirus genome). We also show that replication forks proceed bidirectionally from the origin and converge 180circ opposite the URR. These results demonstrate the feasibility of analysis of replication of viral genomes directly from infected tissue.

Cementitious porous pavement in stormwater quality control: pH and alkalinity elevation.

PubMed

Kuang, Xuheng; Sansalone, John

2011-01-01

A certain level of alkalinity acts as a buffer and maintains the pH value in a stable range in water bodies. With rapid urban development, more and more acidic pollutants flow to watersheds with runoff and drop alkalinity to a very low level and ultimately degrade the water environment. Cementitious porous pavement is an effective tool for stormwater acidic neutralization. When stormwater infiltrates cement porous pavement (CPP) materials, alkalinity and pH will be elevated due to the basic characteristics of cement concrete. The elevated alkalinity will neutralize acids in water bodies and maintain the pH in a stable level as a buffer. It is expected that CPP materials still have a certain capability of alkalinity elevation after years of service, which is important for CPP as an effective tool for stormwater management. However, few previous studies have reported on how CPP structures would elevate runoff alkalinity and pH after being exposed to rainfall-runoff for years. In this study, three groups of CPP specimens, all exposed to rainfall-runoff for 3 years, were used to test the pH and alkalinity elevation properties. It was found that runoff pH values were elevated from 7.4 to the range of 7.8-8.6 after infiltrating through the uncoated specimens, and from 7.4 to 8.5-10.7 after infiltrating through aluminum-coated specimens. Runoff alkalinity elevation efficiencies are 11.5-14.5% for uncoated specimens and 42.2% for coated specimens. The study shows that CPP is an effective passive unit operation for stormwater acid neutralization in our built environment.

Clonal Integration Enhances the Performance of a Clonal Plant Species under Soil Alkalinity Stress

PubMed Central

Sun, Juanjuan; Chen, Jishan; Zhang, Yingjun

2015-01-01

Clonal plants have been shown to successfully survive in stressful environments, including salinity stress, drought and depleted nutrients through clonal integration between original and subsequent ramets. However, relatively little is known about whether clonal integration can enhance the performance of clonal plants under alkalinity stress. We investigated the effect of clonal integration on the performance of a typical rhizomatous clonal plant, Leymus chinensis, using a factorial experimental design with four levels of alkalinity and two levels of rhizome connection treatments, connected (allowing integration) and severed (preventing integration). Clonal integration was estimated by comparing physiological and biomass features between the rhizome-connected and rhizome-severed treatments. We found that rhizome-connected treatment increased the biomass, height and leaf water potential of subsequent ramets at highly alkalinity treatments but did not affect them at low alkalinity treatments. However, rhizome-connected treatment decreased the root biomass of subsequent ramets and did not influence the photosynthetic rates of subsequent ramets. The biomass of original ramets was reduced by rhizome-connected treatment at the highest alkalinity level. These results suggest that clonal integration can increase the performance of clonal plants under alkalinity stress. Rhizome-connected plants showed dramatically increased survival of buds with negative effects on root weight, indicating that clonal integration influenced the resource allocation pattern of clonal plants. A cost-benefit analysis based on biomass measures showed that original and subsequent ramets significantly benefited from clonal integration in highly alkalinity stress, indicating that clonal integration is an important adaptive strategy by which clonal plants could survive in local alkalinity soil. PMID:25790352

Hydrogeology, Water Chemistry, and Factors Affecting the Transport of Contaminants in the Zone of Contribution of a Public-Supply Well in Modesto, Eastern San Joaquin Valley, California

USGS Publications Warehouse

Jurgens, Bryant C.; Burow, Karen R.; Dalgish, Barbara A.; Shelton, Jennifer L.

2008-01-01

Ground-water chemistry in the zone of contribution of a public-supply well in Modesto, California, was studied by the U.S. Geological Survey National Water Quality Assessment (NAWQA) Program's topical team for Transport of Anthropogenic and Natural Contaminants (TANC) to supply wells. Twenty-three monitoring wells were installed in Modesto to record baseline hydraulic information and to collect water-quality samples. The monitoring wells were divided into four categories that represent the chemistry of different depths and volumes of the aquifer: (1) water-table wells were screened between 8.5 and 11.7 m (meter) (28 and 38.5 ft [foot]) below land surface (bls) and were within 5 m (16 ft) of the water table; (2) shallow wells were screened between 29 and 35 m (95 and 115 ft) bls; (3) intermediate wells were screened between 50.6 and 65.5 m (166 and 215 ft) bls; and (4) deep wells are screened between 100 to 106 m (328 and 348 ft) bls. Inorganic, organic, isotope, and age-dating tracers were used to characterize the geochemical conditions in the aquifer and understand the mechanisms of mobilization and movement of selected constituents from source areas to a public-supply well. The ground-water system within the study area has been significantly altered by human activities. Water levels in monitoring wells indicated that horizontal movement of ground water was generally from the agricultural areas in the northeast towards a regional water-level depression within the city in the southwest. However, intensive pumping and irrigation recharge in the study area has caused large quantities of ground water to move vertically downward within the regional and local flow systems. Analysis of age tracers indicated that ground-water age varied from recent recharge at the water table to more than 1,000 years in the deep part of the aquifer. The mean age of shallow ground water was determined to be between 30 and 40 years. Intermediate ground water was determined to be a mixture of modern (Post-1950) and old (Pre-1950) ground water. As a result, concentrations of age tracers were detectable but diluted by older ground water. Deep ground water generally represented water that was recharged under natural conditions and therefore had much older ages. Ground water reaching the public-supply well was a mixture of older intermediate and deep ground water and young shallow ground water that has been anthropogenically-influenced to a greater extent than intermediate ground water. Uranium and nitrate pose the most significant threat to the quality of water discharged from the public-supply well. Although pesticides and VOCs were present in ground water from the public-supply well and monitoring wells, currently concentrations of these contaminants are generally less than one-hundredth the concentration of drinking water standards. In contrast, both uranium and nitrate were above half the concentration of drinking water standards for public-supply well samples, and were above drinking water standards for several water-table and shallow monitoring wells. Shallow ground water contributes roughly 20 percent of the total flow to the public-supply well and was the entry point of most contaminants reaching the public-supply well. Naturally-occurring uranium, which is commonly adsorbed to aquifer sediments, was mobilized by oxygen-rich, high-alkalinity water, causing concentrations in some monitoring wells to be above the drinking-water standard of 30 ug/L (microgram per liter). Adsorption experiments, sediment extractions, and uranium isotopes indicated uranium in water-table and shallow ground water was leached from aquifer sediments. Uranium is strongly correlated to bicarbonate concentrations (as measured by alkalinity) in ground water. Bicarbonate can effectively limit uranium adsorption to sediments. As a result, continued downward movement of high-alkalinity, oxygen-rich ground water will likely lead to larger portions of the aquifer having

Adverse effects of mineral-alkali reactions in alkaline flooding: Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thornton, S.D.

1988-01-01

Two slim-tube experiments and supporting bottle tests were performed for a study of sandstone-alkali reactions. The two samples of reservoir sandstone used are from oilfields in the People's Republic of China. The first sandstone contains 16 percent clay and is from the Gu-Dao oilfield. The second sandstone contains 12 percent clay and is from the Liao-He oilfield. These two sandstones were allowed to react with alkaline solutions in 6-month bottle tests. Each sandstone consumed the most alkali from 0.5 N NaOH solution, an intermediate amount of alkali from 0.5 N Na/sub 2/SiO/sub 3/ solution, and the least amount of alkalimore » from 0.5 N Na/sub 2/CO/sub 3/ solution. 59 refs., 14 figs., 20 tabs.« less

Anaerobic treatment of Tequila vinasses in a CSTR-type digester.

PubMed

Méndez-Acosta, Hugo Oscar; Snell-Castro, Raúl; Alcaraz-González, Víctor; González-Alvarez, Víctor; Pelayo-Ortiz, Carlos

2010-06-01

Tequila industries in general produce great volumes of effluents with high pollutant loads, which are discharged (untreated or partially treated) into natural receivers, thus causing severe environmental problems. In this contribution, we propose an integrated system as a first step to comply with the Mexican ecological norms and stabilize the anaerobic treatment of Tequila vinasses with main design criteria: simple and easy operation, reduce operating time and associated costs (maintenance), integrated and compact design, minimal cost of set-up, start-up, monitoring and control. This system is composed of a fully instrumented and automated lab-scale CSTR-type digester, on-line measuring devices of key variables (pH, temperature, flow rates, etc.), which are used along with off-line readings of chemical oxygen demand (COD), biogas composition, alkalinity and volatile fatty acids to guarantee the operational stability of the anaerobic digestion process. The system performance was evaluated for 200 days and the experimental results show that even under the influence of load disturbances, it is possible to reduce the COD concentration to 85% in the start-up phase and up to 95% during the normal operation phase while producing a biogas with a methane composition greater than 65%. It is also shown that in order to maintain an efficient treatment, the buffering capacity (given by the alkalinity ratio, alpha = intermediate alkalinity/total alkalinity) must be closely monitored.

Enhanced decomposition of 1,4-dioxane in water by ozonation under alkaline condition.

PubMed

Tian, Gui-Peng; Wu, Qian-Yuan; Li, Ang; Wang, Wen-Long; Hu, Hong-Ying

2014-01-01

1,4-Dioxane is a probable human carcinogenic and refractory substance that is widely detected in aquatic environments. Traditional wastewater treatment processes, including activated sludge, cannot remove 1,4-dioxane. Removing 1,4-dioxane with a reaction kinetic constant of 0.32 L/(mol·s) by using ozone, a strong oxidant, is difficult. However, under alkaline environment, ozone generates a hydroxyl radical (•OH) that exhibits strong oxidative potential. Thus, the ozonation of 1,4-dioxane in water under different pH conditions was investigated in this study. In neutral solution, with an inlet ozone feed rate of 0.19 mmol/(L·min), the removal efficiency of 1,4-dioxane was 7.6% at 0.5 h, whereas that in alkaline solution was higher (16.3-94.5%) within a pH range of 9-12. However, the removal efficiency of dissolved organic carbon was considerably lower than that of 1,4-dioxane. This result indicates that several persistent intermediates were generated during 1,4-dioxane ozonation. The pseudo first-order reaction further depicted the reaction of 1,4-dioxane. The obvious kinetic constants (kobs) at pH 9, 10, 11 and 12 were 0.94, 2.41, 24.88 and 2610 L/(mol·s), respectively. Scavenger experiments on radical species indicated that •OH played a key role in removing 1,4-dioxane during ozonation under alkaline condition.

Development of the Use of Alternative Cements for the Treatment of Intermediate Level Waste

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hayes, M.; Godfrey, I.H.

2007-07-01

This paper describes initial development studies undertaken to investigate the potential use of alternative, non ordinary Portland cement (OPC) based encapsulation matrices to treat historic legacy wastes within the UK's Intermediate Level Waste (ILW) inventory. Currently these wastes are encapsulated in composite OPC cement systems based on high replacement with blast furnace slag of pulverised fuel ash. However, the high alkalinity of these cements can lead to high corrosion rates with reactive metals found in some wastes releasing hydrogen and forming expansive corrosion products. This paper therefore details preliminary results from studies on two commercial products, calcium sulfo-aluminate (CSA) andmore » magnesium phosphate (MP) cement which react with a different hydration chemistry, and which may allow wastes containing these metals to be encapsulated with lower reactivity. The results indicate that grouts can be formulated from both cements over a range of water contents and reactant ratios that have significantly improved fluidity in comparison to typical OPC cements. All designed mixes set in 24 hours with zero bleed and the pH values in the plastic state were in the range 10-11 for CSA and 5-7 for MP cements. In addition, a marked reduction in aluminium corrosion rate has been observed in both types of cements compared to a composite OPC system. These results therefore provide encouragement that both cement types can provide a possible alternative to OPC in the immobilisation of reactive wastes, however further investigation is needed. (authors)« less

Importance of water quality in container plant production

Treesearch

John M. Ruter

2013-01-01

High substrate pH is a major problem for producers of container-grown plants and seedlings. The primary cause of high substrate pH is irrigation water with high alkalinity. Alkalinity is defined as the capacity of water to neutralize acids. Some alkalinity in irrigation water is beneficial as it serves as a buffer to large swings in pH levels, but high alkalinity in...

Mechanisms and modelling of waste-cement and cement-host rock interactions

NASA Astrophysics Data System (ADS)

2017-06-01

Safe and sustainable disposal of hazardous and radioactive waste is a major concern in today's industrial societies. The hazardous waste forms originate from residues of thermal treatment of waste, fossil fuel combustion and ferrous/non-ferrous metal smelting being the most important ones in terms of waste production. Low- and intermediate-level radioactive waste is produced in the course of nuclear applications in research and energy production. For both waste forms encapsulation in alkaline, cement-based matrices is considered to ensure long-term safe disposal. Cementitious materials are in routine use as industrial materials and have mainly been studied with respect to their evolution over a typical service life of several decades. Use of these materials in waste management applications, however, requires assessments of their performance over much longer time periods on the order of thousands to several ten thousands of years.

Microbial fouling and corrosion of carbon steel in deep anoxic alkaline groundwater.

PubMed

Rajala, Pauliina; Bomberg, Malin; Vepsäläinen, Mikko; Carpén, Leena

2017-02-01

Understanding the corrosion of carbon steel materials of low and intermediate level radioactive waste under repository conditions is crucial to ensure the safe storage of radioactive contaminated materials. The waste will be in contact with the concrete of repository silos and storage containers, and eventually with groundwater. In this study, the corrosion of carbon steel under repository conditions as well as the microbial community forming biofilm on the carbon steel samples, consisting of bacteria, archaea, and fungi, was studied over a period of three years in a groundwater environment with and without inserted concrete. The number of biofilm forming bacteria and archaea was 1,000-fold lower, with corrosion rates 620-times lower in the presence of concrete compared to the natural groundwater environment. However, localized corrosion was detected in the concrete-groundwater environment indicating the presence of local microenvironments where the conditions for pitting corrosion were favorable.

Intermediate frequency magnetic field generated by a wireless power transmission device does not cause genotoxicity in vitro.

PubMed

Shi, Dejing; Zhu, Chunbo; Lu, Rengui; Mao, Shitong; Qi, Yanhua

2014-10-01

The aim of this study was to evaluate effects of intermediate frequency magnetic fields (IFMF) generated by a wireless power transmission (WPT) based on magnetic resonance from the perspective of cellular genotoxicity on cultured human lens epithelial cells (HLECs). We evaluated the effects of exposure to 90 kHz magnetic fields at 93.36 µT on cellular genotoxicity in vitro for 2 and 4 h. The magnetic flux density is approximately 3.5 times higher than the reference level recommended by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines. For assessment of genotoxicity, we studied cellular proliferation, apoptosis and DNA damage by Cell Counting Kit-8 (CCK-8) assay, flow cytometry analysis, alkaline comet assay and phosphorylated histone H2AX (γH2AX) foci formation test. We did not detect any effect of a 90 kHz IFMF generated by WPT based on magnetic resonance on cell proliferation, apoptosis, comet assay, and γH2AX foci formation test. Our results indicated that exposure to 90 kHz IFMF generated by WPT based on magnetic resonance at 93.36 µT for 2 and 4 h does not cause detectable cellular genotoxicity. © 2014 Wiley Periodicals, Inc.

Efficient photoreductive decomposition of N-nitrosodimethylamine by UV/iodide process.

PubMed

Sun, Zhuyu; Zhang, Chaojie; Zhao, Xiaoyun; Chen, Jing; Zhou, Qi

2017-05-05

N-nitrosodimethylamine (NDMA) has aroused extensive concern as a disinfection byproduct due to its high toxicity and elevated concentration levels in water sources. This study investigates the photoreductive decomposition of NDMA by UV/iodide process. The results showed that this process is an effective strategy for the treatment of NDMA with 99.2% NDMA removed within 10min. The depletion of NDMA by UV/iodide process obeyed pseudo-first-order kinetics with a rate constant (k 1 ) of 0.60±0.03min -1 . Hydrated electrons (e aq - ) generated by the UV irradiation of iodide were proven to play a critical role. Dimethylamine (DMA) and nitrite (NO 2 - ) were formed as the main intermediate products, which completely converted to formate (HCOO - ), ammonium (NH 4 + ) and nitrogen (N 2 ). Therefore, not only the high efficiencies in NDMA destruction, but the elimination of toxic intermediates make UV/iodide process advantageous. A photoreduction mechanism was proposed: NDMA initially absorbed photons to a photoexcited state, and underwent a cleavage of NNO bond under the attack of e aq - . The solution pH had little impact on NDMA removal. However, alkaline conditions were more favorable for the elimination of DMA and NO 2 - , thus effectively reducing the secondary pollution. Copyright © 2016 Elsevier B.V. All rights reserved.

Fecal water genotoxicity in healthy free-living young Italian people.

PubMed

Daniela, Erba; Sara, Soldi; Marcella, Malavolti; Giovanni, Aragone; Meynier, Alexandra; Sophie, Vinoy; Cristina, Casiraghi M

2014-02-01

Dietary habit affects the composition of human feces thus determining intestinal environment and exposure of colon mucosa to risk factors. Fecal water (FW) citotoxicity and genotoxicity were investigated in 33 healthy young Italian people, as well as the relationship between genotoxicity and nutrient intake or microflora composition. Two fecal samples were collected at 2 weeks apart and 3-d dietary diary was recorded for each volunteer. Cytotoxicity was measured using the Trypan Blue Dye Exclusion assay and genotoxicity using the Comet Assay (alkaline single-cell electrophoresis). Fecal bifidobacteria, total microbial count and nutrient intakes were also assessed. High intra- and inter-variability in genotoxicity data and in bacteria counts were found. None of the FW samples were citotoxic, but 90% of FW samples were genotoxic. Seventy five percent indicated intermediate and 15% were highly genotoxic. There was a different sex-related distribution. Genotoxicity was positively correlated to the total lipid intake in females and to the bifidobacteria/total bacteria count ratio in male volunteers. These results demonstrate that the majority of FW samples isolated from free-living Italian people show intermediate level of genotoxicity and sustain a relation between this possible non-invasive marker of colorectal cancer risk with both dietary habits and colonic ecosystem. Copyright © 2013 Elsevier Ltd. All rights reserved.

Visible-Light-Driven Valorization of Biomass Intermediates Integrated with H2 Production Catalyzed by Ultrathin Ni/CdS Nanosheets.

PubMed

Han, Guanqun; Jin, Yan-Huan; Burgess, R Alan; Dickenson, Nicholas E; Cao, Xiao-Ming; Sun, Yujie

2017-11-08

Photocatalytic upgrading of crucial biomass-derived intermediate chemicals (i.e., furfural alcohol, 5-hydroxymethylfurfural (HMF)) to value-added products (aldehydes and acids) was carried out on ultrathin CdS nanosheets (thickness ∼1 nm) decorated with nickel (Ni/CdS). More importantly, simultaneous H 2 production was realized upon visible light irradiation under ambient conditions utilizing these biomass intermediates as proton sources. The remarkable difference in the rates of transformation of furfural alcohol and HMF to their corresponding aldehydes in neutral water was observed and investigated. Aided by theoretical computation, it was rationalized that the slightly stronger binding affinity of the aldehyde group in HMF to Ni/CdS resulted in the lower transformation of HMF to 2,5-diformylfuran compared to that of furfural alcohol to furfural. Nevertheless, photocatalytic oxidation of furfural alcohol and HMF under alkaline conditions led to complete transformation to the respective carboxylates with concomitant production of H 2 .

Ethylene Inhibits Root Elongation during Alkaline Stress through AUXIN1 and Associated Changes in Auxin Accumulation.

PubMed

Li, Juan; Xu, Heng-Hao; Liu, Wen-Cheng; Zhang, Xiao-Wei; Lu, Ying-Tang

2015-08-01

Soil alkalinity causes major reductions in yield and quality of crops worldwide. The plant root is the first organ sensing soil alkalinity, which results in shorter primary roots. However, the mechanism underlying alkaline stress-mediated inhibition of root elongation remains to be further elucidated. Here, we report that alkaline conditions inhibit primary root elongation of Arabidopsis (Arabidopsis thaliana) seedlings by reducing cell division potential in the meristem zones and that ethylene signaling affects this process. The ethylene perception antagonist silver (Ag(+)) alleviated the inhibition of root elongation by alkaline stress. Moreover, the ethylene signaling mutants ethylene response1-3 (etr1-3), ethylene insensitive2 (ein2), and ein3-1 showed less reduction in root length under alkaline conditions, indicating a reduced sensitivity to alkalinity. Ethylene biosynthesis also was found to play a role in alkaline stress-mediated root inhibition; the ethylene overproducer1-1 mutant, which overproduces ethylene because of increased stability of 1-AMINOCYCLOPROPANE-1-CARBOXYLIC ACID SYNTHASE5, was hypersensitive to alkaline stress. In addition, the ethylene biosynthesis inhibitor cobalt (Co(2+)) suppressed alkaline stress-mediated inhibition of root elongation. We further found that alkaline stress caused an increase in auxin levels by promoting expression of auxin biosynthesis-related genes, but the increase in auxin levels was reduced in the roots of the etr1-3 and ein3-1 mutants and in Ag(+)/Co(2+)-treated wild-type plants. Additional genetic and physiological data showed that AUXIN1 (AUX1) was involved in alkaline stress-mediated inhibition of root elongation. Taken together, our results reveal that ethylene modulates alkaline stress-mediated inhibition of root growth by increasing auxin accumulation by stimulating the expression of AUX1 and auxin biosynthesis-related genes. © 2015 American Society of Plant Biologists. All Rights Reserved.

Remediation of aged diesel contaminated soil by alkaline activated persulfate.

PubMed

Lominchar, M A; Santos, A; de Miguel, E; Romero, A

2018-05-01

The present work studies the efficiency of alkaline activated persulfate (PS) to remediate an aged diesel fuel contaminated soil from a train maintenance facility. The Total Petroleum Hydrocarbon (TPH) concentration in soil was approximately 5000mgkg -1 with a ratio of aliphatic:aromatic compounds of 70:30. Aromatic compounds were mainly naphtalenes and phenanthrenes. The experiments were performed in batch mode where different initial concentrations of persulfate (105mM, 210mM and 420mM) and activator:persulfate ratios (2 and 4) were evaluated, with NaOH used as activator. Runs were carried out during 56days. Complete TPH conversion was obtained with the highest concentration of PS and activator, whereas in the other runs the elimination of fuel ranged between 60 and 77%. Besides, the abatement of napthalenes and phenantrenes was faster than aliphatic reduction (i. e. after 4days of treatment, the conversions of the aromatic compounds were around 0.8 meanwhile the aliphatic abatements were 0.55) and no aromatic oxidation intermediates from naphtalenes or phenantrenes were detected. These results show that this technology is effective for the remediation of aged diesel in soil with alkaline pH. Copyright © 2017 Elsevier B.V. All rights reserved.

Revising the role of pH and thermal treatments in aflatoxin content reduction during the tortilla and deep frying processes.

PubMed

Torres, P; Guzmán-Ortiz, M; Ramírez-Wong, B

2001-06-01

Naturally aflatoxin-contaminated corn (Zea mays L.) was made into tortillas, tortilla chips, and corn chips by the traditional and commercial alkaline cooking processes. The traditional nixtamalization (alkaline-cooking) process involved cooking and steeping the corn, whereas the commercial nixtamalization process only steeps the corn in a hot alkaline solution (initially boiling). A pilot plant that includes the cooker, stone grinder, celorio cutter, and oven was used for the experiments. The traditional process eliminated 51.7, 84.5, and 78.8% of the aflatoxins content in tortilla, tortilla chips, and corn chips, respectively. The commercial process was less effective: it removed 29.5, 71.2, and 71.2 of the aflatoxin in the same products. Intermediate and final products did not reach a high enough pH to allow permanent aflatoxin reduction during thermal processing. The cooking or steeping liquor (nejayote) is the only component of the system with a sufficiently high pH (10.2-10.7) to allow modification and detoxification of aflatoxins present in the corn grain. The importance of removal of tip, pericarp, and germ during nixtamalization for aflatoxin reduction in tortilla is evident.

Plutonic rocks in the Mineoka-Setogawa ophiolitic mélange, central Japan: Fragments of middle to lower crust of the Izu-Bonin-Mariana Arc?

NASA Astrophysics Data System (ADS)

Ichiyama, Yuji; Ito, Hisatoshi; Hokanishi, Natsumi; Tamura, Akihiro; Arai, Shoji

2017-06-01

A Paleogene accretionary complex, the Mineoka-Setogawa Belt, is distributed around the Izu Collision Zone, central Japan. Plutonic rocks of gabbro, diorite and tonalite compositions are included as fragments and dykes in an ophiolitic mélange in this belt. Zircon U-Pb dating of the plutonic rocks indicates that they were formed at ca. 35 Ma simultaneously. These ages are consistent with Eocene-Oligocene tholeiite and calc-alkaline arc magmatism in the Izu-Bonin-Mariana (IBM) Arc and exclude several previous models for the origin of the Mineoka-Setogawa ophiolitic rocks. The geochemical characteristics of these plutonic rocks are similar to those of the Eocene-Oligocene IBM tholeiite and calc-alkaline volcanic rocks as well as to the accreted middle crust of the IBM Arc, the Tanzawa Plutonic Complex. Moreover, their lithology is consistent with those of the middle and lower crust of the IBM Arc estimated from the seismic velocity structure. These lines of evidence strongly indicate that the plutonic rocks in the Mineoka-Setogawa ophiolitic mélange are fragments of the middle to lower crust of the IBM Arc. Additionally, the presence of the Mineoka-Setogawa intermediate to felsic plutonic rocks supports the hypothesis that intermediate magma can form continental crust in intra-oceanic arcs.

Simulation of dual carbon-bromine stable isotope fractionation during 1,2-dibromoethane degradation.

PubMed

Jin, Biao; Nijenhuis, Ivonne; Rolle, Massimo

2018-06-01

We performed a model-based investigation to simultaneously predict the evolution of concentration, as well as stable carbon and bromine isotope fractionation during 1,2-dibromoethane (EDB, ethylene dibromide) transformation in a closed system. The modelling approach considers bond-cleavage mechanisms during different reactions and allows evaluating dual carbon-bromine isotopic signals for chemical and biotic reactions, including aerobic and anaerobic biological transformation, dibromoelimination by Zn(0) and alkaline hydrolysis. The proposed model allowed us to accurately simulate the evolution of concentrations and isotope data observed in a previous laboratory study and to successfully identify different reaction pathways. Furthermore, we illustrated the model capabilities in degradation scenarios involving complex reaction systems. Specifically, we examined (i) the case of sequential multistep transformation of EDB and the isotopic evolution of the parent compound, the intermediate and the reaction product and (ii) the case of parallel competing abiotic pathways of EDB transformation in alkaline solution.

Co-administration of α-lipoic acid and glutathione is associated with no significant changes in serum bilirubin, alkaline phosphatase or γ-glutamyltranspeptidase levels during the treatment of neuroborreliosis with intravenous ceftriaxone.

PubMed

Puri, Basant K; Hakkarainen-Smith, Jaana S; Derham, Anne; Monro, Jean A

2015-09-01

While pharmacotherapy with intravenous ceftriaxone, a third-generation cephalosporin, is a potential treatment of Lyme neuroborreliosis, there is concern that it can cause the formation of biliary sludge, leading to hepatobiliary complications such as biliary colic, jaundice and cholelithiasis, which are reflected in changes in serum levels of bilirubin and markers of cholestatic liver injury (alkaline phosphatase and γ-glutamyltranspeptidase). It has been suggested that the naturally occurring substances α-lipoic acid and glutathione may be helpful in preventing hepatic disease. α-Lipoic acid exhibits antioxidant, anti-inflammatory and anti-apoptotic activities in the liver, while glutathione serves as a sulfhydryl buffer. The aim of this study was to determine whether co-administration of α-lipoic acid and glutathione is associated with significant changes in serum levels of bilirubin, alkaline phosphatase and γ-glutamyltranspeptidase during the treatment of Lyme neuroborreliosis with long-term intravenous ceftriaxone. Serum levels of bilirubin, alkaline phosphatase and γ-glutamyltranspeptidase were measured in 42 serologically positive Lyme neuroborreliosis patients before and after long-term treatment with intravenous ceftriaxone (2-4 g daily) with co-administration of oral/intravenous α-lipoic acid (600 mg daily) and glutathione (100 mg orally or 0.6-2.4 g intravenously daily). None of the patients developed biliary colic and there were no significant changes in serum bilirubin, alkaline phosphatase or γ-glutamyltranspeptidase levels over the course of the intravenous ceftriaxone treatment (mean length 75.0 days). Co-administration of α-lipoic acid and glutathione is associated with no significant changes in serum bilirubin, alkaline phosphatase or γ-glutamyltranspeptidase levels during the treatment of neuroborreliosis with intravenous ceftriaxone.

Lateral carbon export in the Mississippi River Basin, integrating fluxes from the headwaters to the Gulf of Mexico

NASA Astrophysics Data System (ADS)

Stackpoole, S. M.; Crawford, J.; Santi, L. M.; Stets, E.; Sebestyen, S. D.; Wilson, S.; Striegl, R. G.

2017-12-01

Large-scale river studies have documented that lateral fluxes are an important component of the global carbon cycle. This study focuses on river lateral C fluxes for the Mississippi River Basin (MRB), the largest river in North America. Our lateral river C fluxes are based on data from 23 nested watersheds within the Upper MRB, for water years 2015 and 2016. The study area covers 170,000 km2 and is comprised of both catchment <10 km2 and intermediate-scale watersheds (20,000 to 40,000 km2) in Wisconsin and Minnesota, USA. Total alkalinity yields (flux derived by drainage area) ranged from 0 to 16 g C m2 yr-1 and dissolved organic C (DOC) yields ranged from 1 to 13 g C m2 yr-1. In comparison, published estimates for Mississippi River export to the Gulf of Mexico, estimated at St. Francisville, LA, were 16 g C m-2 yr-1 for alkalinity and 0.6 g m2 yr-1 for DOC. In the Upper MRB, alkalinity yields had a significant negative relationship with DOC yields (R2 = 0.53, p-value<0.0001), and alkalinity yields were significantly higher in basins where the lithology was dominated by carbonates and the land-use was >50% agriculture. There was significant inter-annual variability in the total C fluxes, and the increase in discharge in 2016 relative to 2015 increased the proportion of DOC:alkalinity for watersheds with higher forest and wetland coverage. The integration of these recent C flux estimates for the Upper MRB integrated with the fluxes estimated from the USGS long-term monitoring program dataset provide a comprehensive analysis of alkalinity and DOC fluxes for the entire basin. These results, which represent C fluxes across a gradient of lithology, soil type, and land use, will be used to address questions related to our understanding of carbon sources, transport, and loss that can be applied to other river systems.

Deciphering the protective role of spermidine against saline-alkaline stress at physiological and proteomic levels in tomato.

PubMed

Zhang, Yi; Zhang, Hao; Zou, Zhi-Rong; Liu, Yi; Hu, Xiao-Hui

2015-02-01

In this research, the protective effect of spermidine (Spd) in mitigating saline-alkaline stress in tomato (Solanum lycopersicum L.) at physiological and proteomic levels were examined. The results showed that saline-alkaline stress induced accumulation of H2O2 and O2(-*), and increased the activities of antioxidase (SOD, CAT, and POD). Spermidine efficiently alleviated the inhibitory role of saline-alkaline on plant growth and inhibited saline-alkaline stress-induced H2O2 and O2(-*) accumulation. Proteomics investigations of the leaves of tomato seedlings, responding to a 75 mM saline-alkaline solution and 0.25 mM Spd, were performed. Maps of the proteome of leaf extracts were obtained by two-dimensional gel electrophoresis. An average of 49, 47 and 34 spots, which appeared repeatedly and that significantly altered the relative amounts of polypeptides by more than twofold, were detected for seedlings treated with saline-alkaline solution (S) compared to normal solution (CK), saline-alkaline plus spermidine (MS) compared to CK, or S versus MS, respectively. Thirty-nine of these proteins were identified by matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry and were classified into five functional categories, including energy and metabolism, signal transduction, amino acid metabolism, protein metabolism, and stress-defense response. Proteomics analysis coupled with bioinformatics indicated that Spd treatment helps tomato seedlings combat saline-alkaline stress by modulating the defense mechanism of plants and activating cellular detoxification, which protect plants from oxidative damage induced by saline-alkaline stress. Copyright © 2014 Elsevier Ltd. All rights reserved.

A tale of two magmas: Petrological insights into mafic and intermediate Plinian volcanism at Volcán de Colima, Mexico

NASA Astrophysics Data System (ADS)

Crummy, J. M.; Savov, I. P.; Morgan, D. J.; Wilson, M.; Loughlin, S.; Navarro-Ochoa, C.

2012-12-01

Volcán de Colima in western Mexico explosively erupts basaltic to high-silica andesitic magmas. Detailed petrological and geochemical analyses of Holocene tephra fallout deposits reveal two distinct magma types: I. typical calc-alkaline series magmas; and II. mixed calc-alkaline - alkaline magmas. Group I magmas comprise basalt to high-silica andesite (50.7 to 60.4 wt.% SiO2) and typically contain phenocrysts of plagioclase + clinopyroxene + orthopyroxene + Fe-Ti oxides ± hornblende ± olivine. Crystallinity varies from 10-25 vol.% dominated by plagioclase in a groundmass comprising highly vesiculated glass with abundant microlites. Back-scatter electron (BSE) microscope images together with electron microprobe analyses (EPMA) reveal complex zoning patterns and compositional variations in plagioclase and pyroxene phenocrysts. Large scale resorption events with dissolution surfaces cross-cutting multiple growth zones, combined with large steps in An content of up to 20 mol.% in plagioclase, and Mg# varying from 0.74 to 0.86 in clinopyroxene and orthopyroxene, indicates destabilisation and recrystallisation in a more mafic melt: increases in Cr coincident with step increases in Mg# reveal mafic magma recharge. Many plagioclase and pyroxene phenocrysts record multiple magma recharge events; while small-scale oscillations reveal compositional fluctuations as a result of decompression and degassing. Group II magmas comprise basalt to basaltic-andesite (48.3 to 57.5 wt.% SiO2) and contain 10-15 vol.% crystals comprising clinopyroxene + olivine + phlogopite + plagioclase + Fe-Ti oxides ± hornblende ± orthopyroxene. The groundmass comprises highly vesiculated glass with abundant microlites of the same mineral phases. Clinopyroxene phenocrysts have magnesian cores (Mg# 0.88-0.89) that display strong dissolution with clear resorption and recrystallisation. EPMA analyses reveal large compositional differences with the surrounding growth zone (Mg# 0.80) indicating recrystallisation and re-equilibration within a compositionally different melt. This composition of the clinopyroxene is similar to that of the Group I magmas. Whole-rock geochemical and Sr and Nd isotopic analyses reveal strong trends in the Group II magmas towards the composition of monogenetic cinder cones composed of phlogopite-bearing alkaline lamprophyre situated to the north of Volcán de Colima. The alkaline magmas are thought to have formed from partial melting of metasomatically enriched veins within the lithospheric mantle. We suggest the high Mg clinopyroxene cores of the Group II magmas crystallised from such alkaline melts, which then mixed with the parental mantle-derived melts of the Group I magmas. Geothermometry and hygrometry based on mineral-mineral and mineral-melt equilibria reveal no correlation between variations in eruption temperature (930-1000°C) and magmatic H2O content (3-6 wt.%) with magma composition. This implies magma composition and volatile content are not controlling the highly explosive mafic and intermediate eruptions at Volcán de Colima, but rather, are driven by very fast ascent rates from source to surface.

ALT1, a Snf2 Family Chromatin Remodeling ATPase, Negatively Regulates Alkaline Tolerance through Enhanced Defense against Oxidative Stress in Rice

PubMed Central

Guo, Mingxin; Wang, Ruci; Wang, Juan; Hua, Kai; Wang, Yueming; Liu, Xiaoqiang; Yao, Shanguo

2014-01-01

Alkaline salt stress adversely affects rice growth, productivity and grain quality. However, the mechanism underlying this process remains elusive. We characterized here an alkaline tolerant mutant, alt1 in rice. Map-based cloning revealed that alt1 harbors a mutation in a chromatin remodeling ATPase gene. ALT1-RNAi transgenic plants under different genetic background mimicked the alt1 phenotype, exhibiting tolerance to alkaline stress in a transcript dosage-dependent manner. The predicted ALT1 protein belonged to the Ris1 subgroup of the Snf2 family and was localized in the nucleus, and transcription of ALT1 was transiently suppressed after alkaline treatment. Although the absorption of several metal ions maintained well in the mutant under alkaline stress, expression level of the genes involved in metal ions homeostasis was not altered in the alt1 mutant. Classification of differentially expressed abiotic stress related genes, as revealed by microarray analysis, found that the majority (50/78) were involved in ROS production, ROS scavenging, and DNA repair. This finding was further confirmed by that alt1 exhibited lower levels of H2O2 under alkaline stress and tolerance to methyl viologen treatment. Taken together, these results suggest that ALT1 negatively functions in alkaline tolerance mainly through the defense against oxidative damage, and provide a potential two-step strategy for improving the tolerance of rice plants to alkaline stress. PMID:25473841

Increased ethanol accumulation from glucose via reduction of ATP level in a recombinant strain of Saccharomyces cerevisiae overexpressing alkaline phosphatase.

PubMed

Semkiv, Marta V; Dmytruk, Kostyantyn V; Abbas, Charles A; Sibirny, Andriy A

2014-05-15

The production of ethyl alcohol by fermentation represents the largest scale application of Saccharomyces cerevisiae in industrial biotechnology. Increased worldwide demand for fuel bioethanol is anticipated over the next decade and will exceed 200 billion liters from further expansions. Our working hypothesis was that the drop in ATP level in S. cerevisiae cells during alcoholic fermentation should lead to an increase in ethanol production (yield and productivity) with a greater amount of the utilized glucose converted to ethanol. Our approach to achieve this goal is to decrease the intracellular ATP level via increasing the unspecific alkaline phosphatase activity. Intact and truncated versions of the S. cerevisiae PHO8 gene coding for vacuolar or cytosolic forms of alkaline phosphatase were fused with the alcohol dehydrogenase gene (ADH1) promoter. The constructed expression cassettes used for transformation vectors also contained the dominant selective marker kanMX4 and S. cerevisiae δ-sequence to facilitate multicopy integration to the genome. Laboratory and industrial ethanol producing strains BY4742 and AS400 overexpressing vacuolar form of alkaline phosphatase were characterized by a slightly lowered intracellular ATP level and biomass accumulation and by an increase in ethanol productivity (13% and 7%) when compared to the parental strains. The strains expressing truncated cytosolic form of alkaline phosphatase showed a prolonged lag-phase, reduced biomass accumulation and a strong defect in ethanol production. Overexpression of vacuolar alkaline phosphatase leads to an increased ethanol yield in S. cerevisiae.

Mechanism of oxygen reduction reaction on Pt(111) in alkaline solution: Importance of chemisorbed water on surface

DOE PAGES

Liu, Shizhong; White, Michael G.; Liu, Ping

2016-06-30

Here, we report a detailed mechanistic study of the oxygen reduction reaction (ORR) on Pt(111) in alkaline solution, combining density functional theory and kinetic Monte Carlo simulations. A complex reaction network including four possible pathways via either 2e – or 4e – transfer is established and is able to reproduce the experimental measured polarization curve at both low- and high-potential regions. Our results show that it is essential to account for solvation by water and the dynamic coverage of *OH to describe the reaction kinetics well. In addition, a chemisorbed water (*H 2O)-mediated mechanism including 4e – transfers is identified,more » where the reduction steps via *H 2O on the surface are potential-independent and only the final removal of *OH from the surface in the form of OH –(aq) contributes to the current. For the ORR in alkaline solutions, such a mechanism is more competitive than the associative and dissociative mechanisms typically used to describe the ORR in acid solution. Finally, *OH and **O 2 intermediates are found to be critically important for tuning the ORR activity of Pt in alkaline solution. To enhance the activity, the binding of Pt should be tuned in such a way that *OH binding is weak enough to release more surface sites under working conditions, while **O 2 binding is strong enough to enable the ORR via the 4e – transfer mechanism.« less

The calc-alkaline and adakitic volcanism of the Sabzevar structural zone (NE Iran): Implications for the Eocene magmatic flare-up in Central Iran

NASA Astrophysics Data System (ADS)

Moghadam, Hadi Shafaii; Rossetti, Federico; Lucci, Federico; Chiaradia, Massimo; Gerdes, Axel; Martinez, Margarita Lopez; Ghorbani, Ghasem; Nasrabady, Mohsen

2016-04-01

A major magmatic flare-up is documented along the Bitlis-Zagros suture zone in Eocene-Oligocene times. The Cenozoic magmatism of intraplate Central Iran is an integrant part of this tectono-magmatic scenario. The Cenozoic magmatism of the Sabzevar structural zone consists of mostly intermediate to felsic intrusions and volcanic products. These igneous rocks have calc-alkaline and adakitic geochemical signatures, with nearly coincident zircon U-Pb and mica Ar-Ar ages of ca. 45 Ma. Adakitic rocks have quite low HREE and high Sr/Y ratio, but share most of their geochemical features with the calc-alkaline rocks. The Sabzevar volcanic rocks have similar initial Sr, Nd and Pb isotope ratios, showing their cogenetic nature. Nd model ages cluster tightly around 0.2-0.3 Ga. The geochemistry of the Sabzevar volcanic rocks, along with their isotopic signatures, might strangle that an upper mantle source, metasomatized by slab-derived melts was involved in generating the Sabzevar calc-alkaline rocks. A bulk rock trace element modeling suggests that amphibole-plagioclase-titanite-dominated replenishment-fractional crystallization (RFC) is further responsible for the formation of the middle Eocene Sabzevar adakitic rocks. Extensional tectonics accompanied by lithospheric delamination, possibly assisted by slab break-off and melting at depth was responsible for the Eocene formation of the Sabzevar magmatic rocks and, more in general, for the magmatic "flare-up" in Iran.

Cystic fibrosis transmembrane conductance regulator contributes to reacidification of alkalinized lysosomes in RPE cells.

PubMed

Liu, Ji; Lu, Wennan; Guha, Sonia; Baltazar, Gabriel C; Coffey, Erin E; Laties, Alan M; Rubenstein, Ronald C; Reenstra, William W; Mitchell, Claire H

2012-07-15

The role of the cystic fibrosis transmembrane conductance regulator (CFTR) in lysosomal acidification has been difficult to determine. We demonstrate here that CFTR contributes more to the reacidification of lysosomes from an elevated pH than to baseline pH maintenance. Lysosomal alkalinization is increasingly recognized as a factor in diseases of accumulation, and we previously showed that cAMP reacidified alkalinized lysosomes in retinal pigmented epithelial (RPE) cells. As the influx of anions to electrically balance proton accumulation may enhance lysosomal acidification, the contribution of the cAMP-activated anion channel CFTR to lysosomal reacidification was probed. The antagonist CFTR(inh)-172 had little effect on baseline levels of lysosomal pH in cultured human RPE cells but substantially reduced the reacidification of compromised lysosomes by cAMP. Likewise, CFTR activators had a bigger impact on cells whose lysosomes had been alkalinized. Knockdown of CFTR with small interfering RNA had a larger effect on alkalinized lysosomes than on baseline levels. Inhibition of CFTR in isolated lysosomes altered pH. While CFTR and Lamp1 were colocalized, treatment with cAMP did not increase targeting of CFTR to the lysosome. The inhibition of CFTR slowed lysosomal degradation of photoreceptor outer segments while activation of CFTR enhanced their clearance from compromised lysosomes. Activation of CFTR acidified RPE lysosomes from the ABCA4(-/-) mouse model of recessive Stargardt's disease, whose lysosomes are considerably alkalinized. In summary, CFTR contributes more to reducing lysosomal pH from alkalinized levels than to maintaining baseline pH. Treatment to activate CFTR may thus be of benefit in disorders of accumulation associated with lysosomal alkalinization.

Cystic fibrosis transmembrane conductance regulator contributes to reacidification of alkalinized lysosomes in RPE cells

PubMed Central

Liu, Ji; Lu, Wennan; Guha, Sonia; Baltazar, Gabriel C.; Coffey, Erin E.; Laties, Alan M.; Rubenstein, Ronald C.; Reenstra, William W.

2012-01-01

The role of the cystic fibrosis transmembrane conductance regulator (CFTR) in lysosomal acidification has been difficult to determine. We demonstrate here that CFTR contributes more to the reacidification of lysosomes from an elevated pH than to baseline pH maintenance. Lysosomal alkalinization is increasingly recognized as a factor in diseases of accumulation, and we previously showed that cAMP reacidified alkalinized lysosomes in retinal pigmented epithelial (RPE) cells. As the influx of anions to electrically balance proton accumulation may enhance lysosomal acidification, the contribution of the cAMP-activated anion channel CFTR to lysosomal reacidification was probed. The antagonist CFTRinh-172 had little effect on baseline levels of lysosomal pH in cultured human RPE cells but substantially reduced the reacidification of compromised lysosomes by cAMP. Likewise, CFTR activators had a bigger impact on cells whose lysosomes had been alkalinized. Knockdown of CFTR with small interfering RNA had a larger effect on alkalinized lysosomes than on baseline levels. Inhibition of CFTR in isolated lysosomes altered pH. While CFTR and Lamp1 were colocalized, treatment with cAMP did not increase targeting of CFTR to the lysosome. The inhibition of CFTR slowed lysosomal degradation of photoreceptor outer segments while activation of CFTR enhanced their clearance from compromised lysosomes. Activation of CFTR acidified RPE lysosomes from the ABCA4−/− mouse model of recessive Stargardt's disease, whose lysosomes are considerably alkalinized. In summary, CFTR contributes more to reducing lysosomal pH from alkalinized levels than to maintaining baseline pH. Treatment to activate CFTR may thus be of benefit in disorders of accumulation associated with lysosomal alkalinization. PMID:22572847

Removal of plutonium and americium from alkaline waste solutions

DOEpatents

Schulz, Wallace W.

1979-01-01

High salt content, alkaline waste solutions containing plutonium and americium are contacted with a sodium titanate compound to effect removal of the plutonium and americium from the alkaline waste solution onto the sodium titanate and provide an effluent having a radiation level of less than 10 nCi per gram alpha emitters.

Recognition and characterisation of high-grade ignimbrites from the Neoproterozoic rhyolitic volcanism in southernmost Brazil

NASA Astrophysics Data System (ADS)

Sommer, Carlos Augusto; Lima, Evandro Fernandes; Machado, Adriane; Rossetti, Lucas de Magalhães May; Pierosan, Ronaldo

2013-11-01

Neoproterozoic magmatism in southern Brazil is associated with translithospheric shear belts and strike-slip basins in a post-collisional setting related to the last stages of the Brasilian-Pan African Orogenic Cycle. It evolved from an association of high-K calc-alkaline, leucocratic-peraluminous and continental tholeiitic magmas, to an association with shoshonitic magmas and, eventually, to an association with magmas of the sodic mildly alkaline series. This magmatism varies from metaluminous to peralkaline and exhibits alkaline sodic affinity. A large volcanism is related to this alkaline sodic magmatism and is named the Acampamento Velho Formation. This unit was coeval with subaerial siliciclastic sedimentation in post-collisional basins preserved in the region. The Acampamento Velho Formation consists of pyroclastic and effusive volcanic deposits, which are mainly silicic, emplaced under subaerial conditions. The best exposures of this volcanism occur on the Ramada and Taquarembó plateaus, located southwest of Rio Grande do Sul in southernmost Brazil. The pyroclastic flow deposits are composed mainly of juvenile fragments such as pumices, shards and crystal fragments. Welding is very effective in these units. High-grade ignimbrites occur at the base and intermediate portions of the deposits and rheoignimbrites are observed at the top. The pre-eruptive temperature calculations, which were obtained at the saturation of zircon, revealed values between 870 °C and 978 °C for Taquarembó Plateau and 850 °C-946 °C for Ramada Plateau. The calculated viscosity values vary from 6.946 to 8.453 log η (Pas) for the rheoignimbrites and 7.818 to 10.588 log η (Pas) for the ignimbrites. Zr contents increase toward the top of the pyroclastic sequence, which indicates an increase in peralkalinity and determines the reduction in viscosity for clasts at the upper portions of the flows. The patterns of the structures of the ignimbrites and rheoignimbrites in the Taquarembó and Ramada plateaus accords well with successive pyroclastic flows that halts en masse. In this model the entire pyroclastic flow halts en masse, so complex vertical changes in grain size and composition are interpreted as recording deposition from successive discrete pyroclastic flows. The stratification observed in intermediate units in Taquarembó Plateau might reflect in this case variation in eruptive dynamics and short pauses.

Alkaline-Earth-Catalyzed Dehydrocoupling of Amines and Boranes

PubMed Central

Liptrot, David J; Hill, Michael S; Mahon, Mary F; Wilson, Andrew S S

2015-01-01

Dehydrocoupling reactions between the boranes HBpin and 9-borabicyclo[3.3.1]nonane and a range of amines and anilines ensue under very mild reaction conditions in the presence of a simple β-diketiminato magnesium n-butyl precatalyst. The facility of the reactions is suggested to be a function of the Lewis acidity of the borane substrate, and is dictated by resultant pre-equilibria between, and the relative stability of, magnesium hydride and borohydride intermediates during the course of the catalysis. PMID:26360523

Effects of Different Saline-Alkaline Conditions on the Characteristics of Phytoplankton Communities in the Lakes of Songnen Plain, China

PubMed Central

Zang, Shuying; Fan, Yawen; Ye, Huaxiang

2016-01-01

Many lakes located in the Songnen Plain of China exhibit a high saline-alkaline level. 25 lakes in the Songnen Plain were selected as research objects in this study. Water samples in these lakes were collected from June to August in 2008. Total Dissolved Solids (TDS) and Total Alkalinity (TA) were measured to assess the saline-alkaline level, and partial canonical correspondence analysis (CCA) was conducted as well. The results show that the majority of these lakes in the study area could be categorized into HCO3−-Na+-I type. According to the TDS assessment, of the total 25 lakes, there are 14 for freshwater, 7 for brackish water and 4 for saltwater; and the respective range of TA was from 0.98 to 40.52. The relationship between TA and TDS indicated significant linear relationship (R2 = 0.9292) in the HCO3−-Na+-I type lakes in the Songnen Plain. There was a general trend that cell density, genera richness and taxonomic diversity decreased with the increase of saline-alkaline gradient, whereas a contrary trend was observed for the proportion of dominant species. When the TDS values were above 3×103mg/L and the TA values were above 15mg/L, there was a significant reduction in cell density, genera richness and biodiversity, and their corresponding values were respectively below 10×106 (ind/L), 15 and approximately 2.5. Through the partial canonical correspondence analysis (CCA), 10.7% of the genera variation was explained by pure saline-alkaline variables. Cyclotella meneghiniana, Melosira ambigua and Melosira granulate were found to become the dominant species in most of these lakes, which indicated that there may be rather wide saline-alkaline niches for common dominant species. About one-quarters of the genera which have certain tolerance to salinity and alkalinity preferred to live in the regions with relatively higher saline-alkaline levels in this study. PMID:27749936

DEVELOPMENT OF COUNTY-LEVEL WIND EROSION AND UNPAVED ROAD ALKALINE EMISSION ESTIMATES FOR THE 1985 NAPAP EMISSIONS INVENTORY

EPA Science Inventory

The report details the methods used and the result of the conversion of the National Acid Precipitation Assessment Program's (NAPAP's) alkaline material emissions information for wind erosion, unpaved roads, and dust devils from the' current spatial resolution to county-level res...

Comparison of enteral and parenteral methods of urine alkalinization in patients receiving high-dose methotrexate.

PubMed

Rouch, Jamie A; Burton, Bradley; Dabb, Alix; Brown, Vicky; Seung, Amy H; Kinsman, Katharine; Holdhoff, Matthias

2017-01-01

Purpose Hyperhydration and urinary alkalinization is implemented with all high-dose (HD)-methotrexate infusions to promote excretion and prevent precipitation of methotrexate in the renal tubules. Our institution utilized enteral alkalinizing agents (sodium bicarbonate tablets and sodium citrate/citric acid solution) to alkalinize the urine of patients receiving HD-methotrexate during a parenteral sodium bicarbonate and sodium acetate shortage. The purpose of this study is to establish the safety and efficacy of the enteral route for urine alkalinization. Methods A single-center, retrospective, cohort study was conducted comparing cycles of HD-methotrexate using enteral alkalinizing agents to parenteral sodium bicarbonate. The primary objective was to compare the time, in hours, from administration of first inpatient administered dose of alkalinizing agent to time of achieving goal urine pH. Secondary objectives evaluated total dose of sodium bicarbonate required to achieve goal urine pH, time from start of urine alkalinizing agent until time of achieving methotrexate level safe for discharge, and toxicities associated with methotrexate and the alkalinizing agents. Results A total of 118 patients were included in this study, equally divided into two cohorts based on parenteral versus enteral routes of administration. No statistical difference was determined between the two cohorts regarding time to goal urine pH (6.5 h versus 7.9 h, P = 0.051) or regarding time to methotrexate level deemed safe for discharge (63.5 h versus 62.5 h, p = 0.835). There were no significant differences in methotrexate-induced toxicities. Conclusion Our study found enteral routes of urine alkalinization to be a viable alternative to the traditional parenteral sodium bicarbonate, especially during parenteral sodium bicarbonate and acetate shortages.

Time evolution of a rifted continental arc: Integrated ID-TIMS and LA-ICPMS study of magmatic zircons from the Eastern Srednogorie, Bulgaria

NASA Astrophysics Data System (ADS)

Georgiev, S.; von Quadt, A.; Heinrich, C. A.; Peytcheva, I.; Marchev, P.

2012-12-01

Eastern Srednogorie in Bulgaria is the widest segment of an extensive magmatic arc that formed by convergence of Africa and Europe during Mesozoic to Tertiary times. Northward subduction of the Tethys Ocean beneath Europe in the Late Cretaceous gave rise to a broad range of basaltic to more evolved magmas with locally associated Cu-Au mineralization along this arc. We used U-Pb geochronology of single zircons to constrain the temporal evolution of the Upper Cretaceous magmatism and the age of basement rocks through which the magmas were emplaced in this arc segment. High precision isotope dilution-thermal ionization mass spectrometry (ID-TIMS) was combined with laser ablation-inductively coupled plasma mass spectrometry (LA-ICPMS) for spatial resolution within single zircon grains. Three tectono-magmatic regions are distinguished from north to south within Eastern Srednogorie: East Balkan, Yambol-Burgas and Strandzha. Late Cretaceous magmatic activity started at ~ 92 Ma in the northernmost East Balkan region, based on stratigraphic evidence and limited geochronology, with the emplacement of minor shallow intrusions and volcanic rocks onto pre-Cretaceous basement. In the southernmost Strandzha region, magmatism was initiated at ~ 86 Ma with emplacement of gabbroic to dioritic intrusions and related dikes into metamorphic basement rocks that have previously been overprinted by Jurassic-Lower Cretaceous metamorphism. The Yambol-Burgas region is an extensional basin between the East Balkan and the Strandzha regions, which broadens and deepens toward the Black Sea further east and is filled with a thick pile of marine sediments and submarine extrusive volcanic rocks accompanied by coeval intrusions. This dominantly mafic magmatism in the intermediate Yambol-Burgas region commenced at ~ 81 Ma and produced large volumes of potassium-rich magma until ~ 78 Ma. These shoshonitic to ultrapotassic basaltic to intermediate magmas formed by differentiation of ankaramitic (high Ca) parental melts, produced from partial remelting of amphibole clinopyroxenites upon interaction with subduction-modified mantle wedge melts, according to earlier petrological studies. This peak of dominantly extrusive activity in the Yambol-Burgas region extended into the Strandzha region further south, in the form of numerous tholeiitic, calc-alkaline and high-K intrusions emplaced in the same time period between 81 and 78 Ma. Granitic rocks from exposed basement of Eastern Srednogorie zone are dated as Permian/Carboniferous (~ 275-300 Ma). Zircons with similar ages occur in Upper Cretaceous rocks from the East Balkan and Strandzha regions, indicating local incorporation as xenocrysts. In contrast, magmatic rocks from the intermediate Yambol-Burgas region contain mostly Ordovician (~ 460 Ma) or older inherited zircons, suggesting a either a different basement history or, more likely, a different level of magma storage and crustal assimilation. Integrating these geochronological results with a synthesis of the regional geology, we propose a two-stage geodynamic evolution for the Eastern Srednogorie segment of the Tethyan arc. The earlier stage of normal arc magmatism was driven by a southward slab retreat, which formed the ~ 92 Ma calc-alkaline to high-K shallow intrusions and volcanics in the north (East Balkan), 87-86 Ma old tholeiitic and calc-alkaline intrusions in the south (Strandzha), and the voluminous 81-78 Ma old gabbroic to granitic intrusions with predominantly calc-alkaline to high-K composition throughout the Strandzha region. This stage continued westward into the Central Srednogorie zone, where the southward younging of calc-alkaline magmatism correlates well with an increased input of primitive mantle melts, indicating asthenospheric incursion into a widening mantle wedge as a result of slab roll-back. The second stage proceeded in the Eastern Srednogorie zone only, where more extreme extension associated with the opening of the Black Sea back-arc basin led to the formation of an intra-arc rift in the Yambol-Burgas region, which now separates the East Balkan region from the Strandzha region. In this extensional environment, crustal thinning lead to decompression and increased heat flow, facilitating large-scale melting of lower crustal rocks and the formation of 81-78 Ma magmas. The unusual calcic composition of the parent magmas, their isotopic character and distinct xenocrystic population are consistent with a component of re-melting of hydrous lower-crustal cumulates, which probably formed in part during the first stage of the evolving arc.

Acetaldehyde as an intermediate in the electroreduction of carbon monoxide to ethanol on oxide-derived copper

DOE PAGES

Bertheussen, Erlend; Verdaguer-Casadevall, Arnau; Ravasio, Davide; ...

2015-12-21

Oxide-derived copper (OD-Cu) electrodes exhibit unprecedented CO reduction performance towards liquid fuels, producing ethanol and acetate with >50 % Faradaic efficiency at -0.3 V (vs. RHE). By using static headspace-gas chromatography for liquid phase analysis, we identify acetaldehyde as a minor product and key intermediate in the electroreduction of CO to ethanol on OD-Cu electrodes. Acetaldehyde is produced with a Faradaic efficiency of ≈5 % at -0.33 V (vs. RHE). We show that acetaldehyde forms at low steady-state concentrations, and that free acetaldehyde is difficult to detect in alkaline solutions using NMR spectroscopy, requiring alternative methods for detection and quantification.more » Our results indicate an important step towards understanding the CO reduction mechanism on OD-Cu electrodes.« less

Serum alkaline phosphatase negatively affects endothelium-dependent vasodilation in naïve hypertensive patients.

PubMed

Perticone, Francesco; Perticone, Maria; Maio, Raffaele; Sciacqua, Angela; Andreucci, Michele; Tripepi, Giovanni; Corrao, Salvatore; Mallamaci, Francesca; Sesti, Giorgio; Zoccali, Carmine

2015-10-01

Tissue nonspecific alkaline phosphatase, promoting arterial calcification in experimental models, is a powerful predictor of total and cardiovascular mortality in general population and in patients with renal or cardiovascular diseases. For this study, to evaluate a possible correlation between serum alkaline phosphatase levels and endothelial function, assessed by strain gauge plethysmography, we enrolled 500 naïve hypertensives divided into increasing tertiles of alkaline phosphatase. The maximal response to acetylcholine was inversely related to alkaline phosphatase (r=−0.55; P<0.001), and this association was independent (r=−0.61; P<0.001) of demographic and classical risk factors, body mass index, estimated glomerular filtration rate, serum phosphorus and calcium, C-reactive protein, and albuminuria. At multiple logistic regression analysis, the risk of endothelial dysfunction was ≈3-fold higher in patients in the third tertile than that of patients in the first tertile. We also tested the combined role of alkaline phosphatase and serum phosphorus on endothelial function. The steepness of the alkaline phosphatase/vasodilating response to acetylcholine relationship was substantially attenuated (P<0.001) in patients with serum phosphorus above the median value when compared with patients with serum phosphorus below the median (−5.0% versus −10.2% per alkaline phosphatase unit, respectively), and this interaction remained highly significant (P<0.001) after adjustment of all the previously mentioned risk factors. Our data support a strong and significant inverse relationship between alkaline phosphatase and endothelium-dependent vasodilation, which was attenuated by relatively higher serum phosphorus levels.

Anoxic Biodegradation of Isosaccharinic Acids at Alkaline pH by Natural Microbial Communities.

PubMed

Rout, Simon P; Charles, Christopher J; Doulgeris, Charalampos; McCarthy, Alan J; Rooks, Dave J; Loughnane, J Paul; Laws, Andrew P; Humphreys, Paul N

2015-01-01

One design concept for the long-term management of the UK's intermediate level radioactive wastes (ILW) is disposal to a cementitious geological disposal facility (GDF). Under the alkaline (10.013.0) anoxic conditions expected within a GDF, cellulosic wastes will undergo chemical hydrolysis. The resulting cellulose degradation products (CDP) are dominated by α- and β-isosaccharinic acids (ISA), which present an organic carbon source that may enable subsequent microbial colonisation of a GDF. Microcosms established from neutral, near-surface sediments demonstrated complete ISA degradation under methanogenic conditions up to pH 10.0. Degradation decreased as pH increased, with β-ISA fermentation more heavily influenced than α-ISA. This reduction in degradation rate was accompanied by a shift in microbial population away from organisms related to Clostridium sporosphaeroides to a more diverse Clostridial community. The increase in pH to 10.0 saw an increase in detection of Alcaligenes aquatilis and a dominance of hydrogenotrophic methanogens within the Archaeal population. Methane was generated up to pH 10.0 with acetate accumulation at higher pH values reflecting a reduced detection of acetoclastic methanogens. An increase in pH to 11.0 resulted in the accumulation of ISA, the absence of methanogenesis and the loss of biomass from the system. This study is the first to demonstrate methanogenesis from ISA by near surface microbial communities not previously exposed to these compounds up to and including pH 10.0.

Orogenic potassic mafic magmatism, a product of alkaline-peraluminous mixing ? Variscan 'calc-alkaline' rocks from the Central Iberian and Ossa Morena Zones, Central Spain.

NASA Astrophysics Data System (ADS)

Scarrow, Jane H.; Cambeses, Aitor; Bea, Fernando; Montero, Pilar; Molina, José F.; Moreno, Juan Antonio

2013-04-01

Orogenic magmatic rocks provide information about mantle and crust melt-generation and -interaction processes. In this context, minor potassic mafic stocks which are formed of enriched mantle and crustal components and are common as late-orogenic intrusions in granitic plutons give insight into the timing of new crust formation and crustal recycling. Potassic mafic stocks are prevalent, albeit low volume, constituents of granite batholiths all through the European Variscan (350-280 Ma). In the Central Iberia Zone, Spanish Central System, crustal-melt, S-type, granitoid plutons are intruded by minor concomitant ultramafic-intermediate appinitic-vaugneritic stocks. Notwithstanding their whole-rock calc-alkaline composition, the stocks apparently did not have a subduction-related origin. Recent studies have attributed their genesis to mixing of alkaline mantle and peraluminous crustal melts. Their primary alkaline character, as indicated by amphibole and biotite mineral chemistry data, points, rather, towards an extension-related genesis. In the Ossa Morena Zone, south of the Central Iberian Zone, the igneous rocks also have a whole-rock calc-alkaline composition which has been considered to be the result of northward subduction of the South Portuguese Zone. Nevertheless, identification of a 'sill' of significant volume of mafic magma in the middle crust, the ´IBERSEIS reflective body', in a seismic profile across the Ossa Morena and South Portuguese Zones has cast doubt upon the calc-alkaline magmatism-subduction model; leading, instead, to the magmatism being attributed to intra-orogenic extension related to a mantle plume active from 340 Ma to 330 Ma. The aim here, then, is to reinvestigate the petrogenesis and age of the calc-alkaline rocks of the Ossa Morena Zone to determine their tectonomagmatic context be it subduction-, plume- or extension-related, and establish what they may reveal about mantle-crust interactions. Focussing, initially, on the Valencia del Ventoso pluton, preliminary mineral chemistry, whole-rock and isotope data indicate that rather than a single-stage cogenetic calc-alkaline intrusion, the pluton is a multi-stage composite of compositionally diverse stocks. Including the metaluminous calc-alkaline Medina de las Torres gabbro and Cortijo del Pozuelo granite to the concentrically zone alkaline core though to calk-alkaline border of the main pluton. In addition, an associated older peraluminous La Jineta granite body and younger cross-cutting tholeiitic dykes crop out in the same region. Here we present new U-Pb single zircon IBERSIMS SHRIMP data which indicate that the compositionally diverse main pluton and associated stocks are contemporaneous at 334 ± 2 Ma. So, rather than reflecting reactivation of a zone of lithospheric weakness by successive magmatic events it appears that at Valencia del Ventoso diverse mantle and crustal sources were being tapped simultaneously. We suggest that this is linked to the generation of and thermal anomaly associated with the coeval ´IBERSEIS reflective body'. The question is, then, if other 'calc-alkaline' plutons have similar compositional, and so, possible tectonomagmatic complexity. To test this hypothesis studies are currently underway of the Ossa Morena Zone Burguillos del Cerro and Brovales plutons.

Production of lignin based insoluble polymers (anionic hydrogels) by C. versicolor.

PubMed

Brzonova, Ivana; Kozliak, Evguenii I; Andrianova, Anastasia A; LaVallie, Audrey; Kubátová, Alena; Ji, Yun

2017-12-13

Unlike previous lignin biodegradation studies, white rot fungi were used to produce functional biopolymers from Kraft lignin. Lignin-based polymers (hydrogel precursors) partially soluble in both aqueous and organic solvents were produced employing a relatively fast (6 days) enzymation of Kraft lignin with basidiomycetes, primarily Coriolus versicolor, pre-grown on kenaf/lignin agar followed by either vacuum evaporation or acid precipitation. After drying followed by a treatment with alkaline water, this intermediate polymer became a pH-sensitive anionic hydrogel insoluble in either aqueous or organic solvents. The yield of this polymer increased from 20 to 72 wt% with the addition of 2% dimethylsulfoxide to distilled water used as a medium. The mechanical stability and buffering capacity of this hydrogel can be adjusted by washing the intermediate polymer/hydrogel precursor prior to drying with solvents of different polarity (water, methanol or ethanol). Any of these polymers featured a significant thermal resilience assessed as a high thermostable "coked" fraction in thermal carbon analysis, apparently resulting from significant covalent cross-linking that occurs during the treatment of their intermediate precursors.

Significantly enhancing recombinant alkaline amylase production in Bacillus subtilis by integration of a novel mutagenesis-screening strategy with systems-level fermentation optimization.

PubMed

Ma, Yingfang; Shen, Wei; Chen, Xianzhong; Liu, Long; Zhou, Zhemin; Xu, Fei; Yang, Haiquan

2016-01-01

Alkaline amylase has significant potential for applications in the textile, paper and detergent industries, however, low yield of which cannot meet the requirement of industrial application. In this work, a novel ARTP mutagenesis-screening method and fermentation optimization strategies were used to significantly improve the expression level of recombinant alkaline amylase in B. subtilis 168. The activity of alkaline amylase in mutant B. subtilis 168 mut-16# strain was 1.34-fold greater than that in the wild-type, and the highest specific production rate was improved from 1.31 U/(mg·h) in the wild-type strain to 1.57 U/(mg·h) in the mutant strain. Meanwhile, the growth of B. subtilis was significantly enhanced by ARTP mutagenesis. When the agitation speed was 550 rpm, the highest activity of recombinant alkaline amylase was 1.16- and 1.25-fold of the activities at 450 and 650 rpm, respectively. When the concentration of soluble starch and soy peptone in the initial fermentation medium was doubled, alkaline amylase activity was increased 1.29-fold. Feeding hydrolyzed starch and soy peptone mixture or glucose significantly improved cell growth, but inhibited the alkaline amylase production in B. subtilis 168 mut-16#. The highest alkaline amylase activity by feeding hydrolyzed starch reached 591.4 U/mL, which was 1.51-fold the activity by feeding hydrolyzed starch and soy peptone mixture. Single pulse feeding-based batch feeding at 10 h favored the production of alkaline amylase in B. subtilis 168 mut-16#. The results indicated that this novel ARTP mutagenesis-screening method could significantly improve the yield of recombinant proteins in B. subtilis . Meanwhile, fermentation optimization strategies efficiently promoted expression of recombinant alkaline amylase in B. subtilis 168 mut-16#. These findings have great potential for facilitating the industrial-scale production of alkaline amylase and other enzymes, using B. subtilis cultures as microbial cell factories.

Expression of a bacterial, phenylpropanoid-metabolizing enzyme in tobacco reveals essential roles of phenolic precursors in normal leaf development and growth.

PubMed

Merali, Zara; Mayer, Melinda J; Parker, Mary L; Michael, Anthony J; Smith, Andrew C; Waldron, Keith W

2012-06-01

Tobacco plants (Nicotiana tabacum cv XHFD 8) were genetically modified to express a bacterial 4-hydroxycinnamoyl-CoA hydratase/lyase (HCHL) enzyme which is active with intermediates of the phenylpropanoid pathway. We have previously shown that HCHL expression in tobacco stem resulted in various pleiotropic effects, indicative of a reduction in the carbon flux through the phenylpropanoid pathway, accompanied by an abnormal phenotype. Here, we report that in addition to the reduction in lignin and phenolic biosynthesis, HCHL expression also resulted in several gross morphological changes in poorly lignified tissue, such as abnormal mesophyll and palisade. The effect of HCHL expression was also noted in lignin-free single cells, with suspension cultures displaying an altered shape and different growth patterns. Poorly/non-lignified cell walls also exhibited a greater ease of alkaline extractability of simple phenolics and increased levels of incorporation of vanillin and vanillic acid. However, HCHL expression had no significant effect on the cell wall carbohydrate chemistry of these tissues. Evidence from this study suggests that changes in the transgenic lines result from a reduction in phenolic intermediates which have an essential role in maintaining structural integrity of low-lignin or lignin-deprived cell walls. These results emphasize the importance of the intermediates and products of phenylpropanoid pathway in modulating aspects of normal growth and development of tobacco. Analysis of these transgenic plants also shows the plasticity of the lignification process and reveals the potential to bioengineer plants with reduced phenolics (without deleterious effects) which could enhance the bioconversion of lignocellulose for industrial applications. Copyright © Physiologia Plantarum 2012.

Estimation and Comparison of Salivary Calcium, Phosphorous, Alkaline Phosphatase and pH Levels in Periodontal Health and Disease: A Cross-sectional Biochemical Study.

PubMed

Patel, Rufi Murad; Varma, Siddhartha; Suragimath, Girish; Zope, Sameer

2016-07-01

In oral diagnostics there is a great challenge to determine biomarkers for screening and evaluating the disease activity. Biomarkers can also serve as a useful tool to measure the efficacy of the therapy. To evaluate and compare the levels of salivary calcium, phosphorous, alkaline phosphatase and pH levels in periodontally healthy subjects and patients with gingivitis and periodontitis. The present study consisted of 150 subjects aged between 20-45 years who were divided into three groups; periodontally healthy, gingivitis and chronic periodontitis. Prior to the clinical examination the demographic details, relevant information of the subject, gingival index, plaque index, Oral Hygiene Index (OHI) and pH were recorded. Biochemical assay of saliva i.e., inorganic calcium, phosphorous and alkaline phosphatase were estimated by colorimetric method. ANOVA and Tukey's test were applied for statistical analysis. The mean levels of biomarkers studied were; inorganic calcium (12.55μg/dl), phosphorous (14.50μg/dl), alkaline phosphatase (49.62μg/dl) and pH (11.65). There was a gradual increase in these levels as the condition progressed from health to gingivitis or periodontitis which was statistically significant at p<0.001. Based on these results, it can be concluded that, the biomarkers like salivary calcium, phosphorous, alkaline phosphatase and pH can be considered for evaluating the diagnosis and prognosis of periodontal tissues in disease and health.

Mechanisms and Kinetics of Alkaline Hydrolysis of the Energetic Nitroaromatic Compounds 2,4,6-Trinitrotoluene (TNT) and 2,4-Dinitroanisole (DNAN)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Salter-Blanc, Alexandra J.; Bylaska, Eric J.; Ritchie, Julia J.

2013-07-02

The environmental impacts of energetic compounds can be minimized through the design and selection of new energetic materials with favorable fate properties. Building predictive models to inform this process, however, is difficult because of uncertainties and complexities in some major fate-determining transformation reactions such as the alkaline hydrolysis of energetic nitroaromatic compounds (NACs). Prior work on the mechanisms of the reaction between NACs and OH– has yielded inconsistent results. In this study, the alkaline hydrolysis of 2,4,6-trinitrotoluene (TNT) and 2,4-dinitroanisole (DNAN) was investigated with coordinated experimental kinetic measurements and molecular modeling calculations. For TNT, the results suggest reversible formation ofmore » an initial product, which is likely either a Meisenheimer complex or a TNT anion formed by abstraction of a methyl proton by OH–. For DNAN, the results suggest that a Meisenheimer complex is an intermediate in the formation of 2,4-dinitrophenolate. Despite these advances, the remaining uncertainties in the mechanisms of these reactions—and potential variability between the hydrolysis mechanisms for different NACs—mean that it is not yet possible to generalize the results into predictive models (e.g., quantitative structure–activity relationships, QSARs) for hydrolysis of other NACs.« less

Mechanisms and kinetics of alkaline hydrolysis of the energetic nitroaromatic compounds 2,4,6-trinitrotoluene (TNT) and 2,4-dinitroanisole (DNAN).

PubMed

Salter-Blanc, Alexandra J; Bylaska, Eric J; Ritchie, Julia J; Tratnyek, Paul G

2013-07-02

The environmental impacts of energetic compounds can be minimized through the design and selection of new energetic materials with favorable fate properties. Building predictive models to inform this process, however, is difficult because of uncertainties and complexities in some major fate-determining transformation reactions such as the alkaline hydrolysis of energetic nitroaromatic compounds (NACs). Prior work on the mechanisms of the reaction between NACs and OH(-) has yielded inconsistent results. In this study, the alkaline hydrolysis of 2,4,6-trinitrotoluene (TNT) and 2,4-dinitroanisole (DNAN) was investigated with coordinated experimental kinetic measurements and molecular modeling calculations. For TNT, the results suggest reversible formation of an initial product, which is likely either a Meisenheimer complex or a TNT anion formed by abstraction of a methyl proton by OH(-). For DNAN, the results suggest that a Meisenheimer complex is an intermediate in the formation of 2,4-dinitrophenolate. Despite these advances, the remaining uncertainties in the mechanisms of these reactions-and potential variability between the hydrolysis mechanisms for different NACs-mean that it is not yet possible to generalize the results into predictive models (e.g., quantitative structure-activity relationships, QSARs) for hydrolysis of other NACs.

Surface Proton Transfer Promotes Four-Electron Oxygen Reduction on Gold Nanocrystal Surfaces in Alkaline Solution

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lu, Fang; Zhang, Yu; Liu, Shizhong

Four-electron oxygen reduction reaction (4e-ORR), as a key pathway in energy conversion, is preferred over the two-electron reduction pathway that falls short in dissociating dioxygen molecules. Gold (Au) surfaces exhibit high sensitivity of the ORR pathway to its atomic structures. The long-standing puzzle remains unsolved why the Au surfaces with {100} sub-facets were exceptionally capable to catalyze the 4e-ORR in alkaline solution, though limited within a narrow potential window. Herein we report the discovery of a dominant 4e-ORR over the whole potential range on {310} surface of Au nanocrystal shaped as truncated ditetragonal prism (TDP). In contrast, ORR pathways onmore » single-crystalline facets of shaped nanoparticles, including {111} on nano-octahedra and {100} on nano-cubes, are similar to their single-crystal counterparts. Combining our experimental results with density functional theory calculations, we elucidate the key role of surface proton transfers from co-adsorbed H 2O molecules in activating the facet- and potential-dependent 4e ORR on Au in alkaline solutions. These results elucidate how surface atomic structures determine the reaction pathways via bond scission and formation among weakly adsorbed water and reaction intermediates. The new insight helps in developing facet-specific nanocatalysts for various reactions.« less

Electrochemically reduced graphene-oxide supported bimetallic nanoparticles highly efficient for oxygen reduction reaction with excellent methanol tolerance

NASA Astrophysics Data System (ADS)

Yasmin, Sabina; Cho, Sung; Jeon, Seungwon

2018-03-01

We report a simple and facile method for the fabrication of bimetallic nanoparticles on electrochemically reduced graphene oxide (ErGO) for electrocatalytic oxygen reduction reaction (ORR) in alkaline media. First, reduced graphene oxide supported palladium and manganese oxide nanoparticle (rGO/Pd-Mn2O3) catalyst was synthesized via a simple chemical method at room temperature; then, it was electrochemically reduced for oxidation reduction reaction (ORR) in alkaline media. The chemical composition and morphological properties of ErGO/Pd-Mn2O3 was characterized by X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and energy-dispersive X-ray spectroscopy (EDS). The TEM images reveals that, nano-sized Pd and Mn2O3 particles were disperse on the ErGO sheet without aggregation. The as-prepared ErGO/Pd-Mn2O3 was employed for ORR in alkaline media which shows higher ORR activity with more positive onset and half-wave potential, respectively. Remarkably, ErGO/Pd-Mn2O3 reduced oxygen via four-electron transfer pathway with negligible amount of intermediate peroxide species (HO2-). Furthermore, the higher stability and excellent methanol tolerance of the ErGO/Pd-Mn2O3 compared to commercial Pt/C (20 wt%) catalyst, indicating its suitability for fuel cells.

Surface Proton Transfer Promotes Four-Electron Oxygen Reduction on Gold Nanocrystal Surfaces in Alkaline Solution

DOE PAGES

Lu, Fang; Zhang, Yu; Liu, Shizhong; ...

2017-05-11

Four-electron oxygen reduction reaction (4e-ORR), as a key pathway in energy conversion, is preferred over the two-electron reduction pathway that falls short in dissociating dioxygen molecules. Gold (Au) surfaces exhibit high sensitivity of the ORR pathway to its atomic structures. The long-standing puzzle remains unsolved why the Au surfaces with {100} sub-facets were exceptionally capable to catalyze the 4e-ORR in alkaline solution, though limited within a narrow potential window. Herein we report the discovery of a dominant 4e-ORR over the whole potential range on {310} surface of Au nanocrystal shaped as truncated ditetragonal prism (TDP). In contrast, ORR pathways onmore » single-crystalline facets of shaped nanoparticles, including {111} on nano-octahedra and {100} on nano-cubes, are similar to their single-crystal counterparts. Combining our experimental results with density functional theory calculations, we elucidate the key role of surface proton transfers from co-adsorbed H 2O molecules in activating the facet- and potential-dependent 4e ORR on Au in alkaline solutions. These results elucidate how surface atomic structures determine the reaction pathways via bond scission and formation among weakly adsorbed water and reaction intermediates. The new insight helps in developing facet-specific nanocatalysts for various reactions.« less

In vitro nonenzymatic glycation of DNA nucleobases: an evaluation of advanced glycation end products under alkaline pH.

PubMed

Dutta, Udayan; Cohenford, Menashi A; Guha, Madhumita; Dain, Joel A

2006-11-01

The advanced glycation end products (AGEs) of DNA nucleobases have received little attention, perhaps due to the fact that adenine, guanine, cytosine and thymine do not dissolve under mild pH conditions. To maintain nucleobases in solution, alkaline pH conditions are typically required. The objectives of this investigation were twofold: to study the susceptibility of DNA nucleobases to nonenzymatic attack by different sugars, and to evaluate the factors that influence the formation of nucleobase AGEs at pH 12, i.e., in an alkaline environment that promotes the aldo-keto isomerization and epimerization of sugars. Varying concentrations of adenine, guanine, thymine and cytosine were incubated over time with constant concentrations of D-glucose, D-galactose or D/L-glyceraldehyde under different conditions of temperature and ionic strength. Incubation of the nucleobases with the sugars resulted in a heterogeneous assembly of AGEs whose formation was monitored by UV/fluorescence spectroscopy. Capillary electrophoresis and HPLC were used to resolve the AGEs of the DNA adducts and provided a powerful tool for following the extent of glycation in each of the DNA nucleobases. Mass spectrometry studies of DNA adducts of guanine established that glycation at pH 12 proceeded through an Amadori intermediate.

Let's think in alkaline phosphatase at heart function.

PubMed

Martins, Maria João; Azevedo, Isabel

2010-10-08

In their recent paper, Cheung et al [B.M. Cheung, K.L. Ong, L.Y. Wong, Elevated serum alkaline phosphatase and peripheral arterial disease in the United States National Health and Nutrition Examination Survey 1999-2004. Int J Cardiol 2008 (Electronic publication ahead of print)] described a significant association between serum alkaline phosphatase levels and low ankle-brachial blood pressure index, a risk factor for cardiovascular pathology. We had verified that alkaline phosphatase is present at the rat heart, showing a distribution compatible with cardiomyocyte sarcoplasmic reticulum. Moreover, several drugs with cardiac effect were shown to interfere with heart alkaline phosphatase activity. We therefore propose that alkaline phosphatase may be a local regulator at heart function and a putative target for therapeutic interventions. Copyright © 2009 Elsevier Ireland Ltd. All rights reserved.

The relationship between glucose metabolism, metabolic syndrome, and bone-specific alkaline phosphatase: a structural equation modeling approach.

PubMed

Cheung, Ching-Lung; Tan, Kathryn C B; Lam, Karen S L; Cheung, Bernard M Y

2013-09-01

Serum alkaline phosphatase plays a role in vascular calcification. It is found in various tissues, whereas bone-specific alkaline phosphatase (BAP) more specifically reflects mineral metabolism. The relationship of serum alkaline phosphatase (total and bone-specific) with diabetes and metabolic syndrome (MetS), 2 major risk factors of vascular calcification, is largely unknown. We aimed to investigate the relationships between glucose metabolism, components of the MetS, and alkaline phosphatase. This was a cross-sectional study of a nationally representative sample of the U.S. population in 1999 through 2004. Participants were 3773 nondiabetic participants of the National Health and Nutrition Examination Survey 1999-2004. We measured serum BAP and total alkaline phosphatase. In multivariable linear regression, updated homeostasis model assessment (HOMA2) for insulin resistance (β = 0.068), HOMA2 for β-cell function (β = 0.081), insulin (β = 0.065), mean arterial pressure (β = 0.15), and high-density lipoprotein (HDL)-cholesterol (β = 0.209) were positively associated with BAP, whereas HOMA2 for insulin sensitivity (β = -0.065) was negatively associated with BAP. On the other hand, only mean arterial pressure and HDL-cholesterol were significantly associated with total alkaline phosphatase. Moreover, a structural equation model revealed that hypertension, low HDL, and insulin resistance had significant direct effects on serum BAP levels, whereas obesity and inflammation might have indirect effects on serum BAP levels. The overall model showed very good fit to the data (comparative fit index = 0.995, root mean square error of approximation = 0.037, and standardized root mean square residual = 0.006). Glucose metabolism and MetS are significantly related to serum BAP levels. How BAP mediates vascular calcification in diabetes and MetS warrants further studies.

Combination Therapy of All-Trans Retinoic Acid With Ursodeoxycholic Acid in Patients With Primary Sclerosing Cholangitis: A Human Pilot Study.

PubMed

Assis, David N; Abdelghany, Osama; Cai, Shi-Ying; Gossard, Andrea A; Eaton, John E; Keach, Jill C; Deng, Yanhong; Setchell, Kenneth D R; Ciarleglio, Maria; Lindor, Keith D; Boyer, James L

2017-02-01

To perform an exploratory pilot study of all-trans retinoic acid (ATRA) combined with ursodeoxycholic acid (UDCA) in patients with primary sclerosing cholangitis (PSC). PSC is a progressive disorder for which there is no accepted therapy. Studies in human hepatocyte cultures and in animal models of cholestasis indicate that ATRA might have beneficial effects in cholestatic disorders. ATRA (45 mg/m/d, divided and given twice daily) was combined with moderate-dose UDCA in patients with PSC who had incomplete response to UDCA monotherapy. The combination was administered for 12 weeks, followed by a 12-week washout in which patients returned to UDCA monotherapy. We measured alkaline phosphatase (ALP), alanine aminotransferase (ALT), bilirubin, cholesterol, bile acids, and the bile acid intermediate 7α-hydroxy-4-cholesten-3-one (C4) at baseline, week 12, and after washout. Fifteen patients completed 12 weeks of therapy. The addition of ATRA to UDCA reduced the median serum ALP levels (277±211 to 243±225 U/L, P=0.09) although this, the primary endpoint, did not reach significance. In contrast, median serum ALT (76±55 to 46±32 U/L, P=0.001) and C4 (9.8±19 to 7.9±11 ng/mL, P=0.03) levels significantly decreased. After washout, ALP and C4 levels nonsignificantly increased, whereas ALT levels significantly increased (46±32 to 74±74, P=0.0006), returning to baseline. In this human pilot study, the combination of ATRA and UDCA did not achieve the primary endpoint (ALP); however, it significantly reduced ALT and the bile acid intermediate C4. ATRA appears to inhibit bile acid synthesis and reduce markers of inflammation, making it a potential candidate for further study in PSC (NCT 01456468).

Alkaline hydrolysis of the cyclic nitramine explosives RDX, HMX, and CL-20: new insights into degradation pathways obtained by the observation of novel intermediates.

PubMed

Balakrishnan, Vimal K; Halasz, Annamaria; Hawari, Jalal

2003-05-01

Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX, I) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) hydrolyze at pH > 10 to form end products including NO2-, HCHO, HCOOH, NH3, and N2O, but little information is available on intermediates, apart from the tentatively identified pentahydro-3,5-dinitro-1,3,5-triazacyclohex-1-ene (II). Despite suggestions that RDX and HMX contaminated groundwater could be economically treated via alkaline hydrolysis, the optimization of such a process requires more detailed knowledge of intermediates and degradation pathways. In this study, we hydrolyzed the monocyclic nitramines RDX, MNX (hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine), and HMX in aqueous solution (pH 10-12.3) and found that nitramine removal was accompanied by formation of 1 molar equiv of nitrite and the accumulation of the key ring cleavage product 4-nitro-2,4-diazabutanal (4-NDAB, O2NNHCH2NHCHO). Most of the remaining C and N content of RDX, MNX, and HMX was found in HCHO, N2O, HCOOH, and NH3. Consequently, we selected RDX as a model compound and hydrolyzed it in aqueous acetonitrile solutions (pH 12.3) in the presence and absence of hydroxypropyl-beta-cyclodextrin (HP-beta-CD) to explore other early intermediates in more detail. We observed a transient LC-MS peak with a [M-H] at 192 Da that was tentatively identified as 4,6-dinitro-2,4,6-triaza-hexanal (O2NNHCH2NNO2CH2NHCHO, III) considered as the hydrolyzed product of II. In addition, we detected another novel intermediate with a [M-H] at 148 Da that was tentatively identified as a hydrolyzed product of III, namely, 5-hydroxy-4-nitro-2,4-diaza-pentanal (HOCH2NNO2CH2NHCHO, IV). Both III and IV can act as precursors to 4-NDAB. In the case of the polycyclic nitramine 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20), denitration (two NO2-) also led to the formation of HCOOH, NH3, and N2O, but neither HCHO nor 4-NDAB were detected. The results provide strong evidence that initial denitration of cyclic nitramines in water is sufficient to cause ring cleavage followed by spontaneous decomposition to form the final products.

Synergistic and Antagonistic Effects of Salinity and pH on Germination in Switchgrass (Panicum virgatum L.)

PubMed Central

Liu, Yuan; Wang, Quanzhen; Zhang, Yunwei; Cui, Jian; Chen, Guo; Xie, Bao; Wu, Chunhui; Liu, Haitao

2014-01-01

The effects of salt-alkaline mixed stress on switchgrass were investigated by evaluating seed germination and the proline, malondialdehyde (MDA) and soluble sugar contents in three switchgrass (Panicum virgatum L.) cultivars in order to identify which can be successfully produced on marginal lands affected by salt-alkaline mixed stress. The experimental conditions consisted of four levels of salinity (10, 60, 110 and 160 mM) and four pH levels (7.1, 8.3, 9.5 and 10.7). The effects of salt-alkaline mixed stress with equivalent coupling of the salinity and pH level on the switchgrass were explored via model analyses. Switchgrass was capable of germinating and surviving well in all treatments under low-alkaline pH (pH≤8.3), regardless of the salinity. However, seed germination and seedling growth were sharply reduced at higher pH values in conjunction with salinity. The salinity and pH had synergetic effects on the germination percentage, germination index, plumular length and the soluble sugar and proline contents in switchgrass. However, these two factors exhibited antagonistic effects on the radicular length of switchgrass. The combined effects of salinity and pH and the interactions between them should be considered when evaluating the strength of salt-alkaline mixed stress. PMID:24454834

Efficacy of Alkali-treated Sugarcane Fiber for Improving Physicochemical and Textural Properties of Meat Emulsions with Different Fat Levels.

PubMed

Kim, Hyun-Wook; Setyabrata, Derico; Lee, Yong-Jae; Brad Kim, Yuan H

2018-04-01

The objective of this study was to evaluate the efficacy of alkaline-treated sugarcane bagasse fiber on physicochemical and textural properties of meat emulsion with different fat levels. Crude sugarcane bagasse fiber (CSF) was treated with calcium hydroxide (Ca(OH 2 )) to obtain alkaline-treated sugarcane bagasse fiber (ASF). The two types of sugarcane bagasse fiber (CSF and ASF) were incorporated at 2% levels in pork meat emulsions prepared with 5%, 10% and 20% fat levels. Alkaline-treatment markedly increased acid detergent fiber content ( p =0.002), but significantly decreased protein, fat, ash and other carbohydrate contents. ASF exhibited significantly higher water-binding capacity, but lower oil-binding and emulsifying capacities than CSF. Meat emulsions formulated with 10% fat and 2% sugarcane bagasse fiber had equivalent cooking loss and textural properties to control meat emulsion (20% fat without sugarcane bagasse fiber). The two types of sugarcane bagasse fiber had similar impacts on proximate composition, cooking yield and texture of meat emulsion at the same fat level, respectively ( p >0.05). Our results confirm that sugarcane bagasse fiber could be a functional food ingredient for improving physicochemical and textural properties of meat emulsion, at 2% addition level. Further, the altered functional properties of alkaline-treated sugarcane bagasse fiber had no impacts on physicochemical and textural properties of meat emulsions, regardless of fat level at 5%, 10% and 20%.

Late Cenozoic alkaline volcanism in the northwestern Caribbean - Tectonic setting and Sr isotopic characteristics

NASA Technical Reports Server (NTRS)

Wadge, G.; Wooden, J. L.

1982-01-01

The northwestern corner of the Caribbean plate has at least sixteen centers of alkalic volcanism, most of which is Quaternary in age. Sr-87/Sr-86 ratios of the rocks in these centers are used to distinguish three geographical groups: a low-ratio group (0.7026-0.7031) at the Nicaraguan Rise, an intermediate-ratio group (0.7036-0.7038) in northeastern Costa Rica, and a high-ratio group (0.7047-0.7063) in Hispaniola. It is suggested that the increased radiogenic strontium in both Costa Rica and Hispaniola may have come from volatile-rich fluids escaping from adjacent subducting slabs of oceanic crust. The isotopic differences between the two areas is explained by the relative longevity and high rate of subduction in Costa Rica compared to that in Hispaniola. The Costa Rican alkaline rocks cover a segment of the Cocos plate which is being subducted at a smaller angle (about 35 deg) than at the rest of the Central American arc.

Alkaline phosphatase, 5'-nucleotidase and magnesium-dependent adenosine triphosphatase activities in the transitional epithelium of the rat urinary bladder.

PubMed

Zhang, S X; Kobayashi, T; Okada, T; García del Saz, E; Seguchi, H

1991-07-01

The cerium-based method was used to demonstrate cytochemically the ultrastructural localization of alkaline phosphatase (ALPase), 5'-nucleotidase (5'-Nase) and magnesium-dependent adenosine triphosphatase (Mg-ATPase) on the transitional epithelium of the rat urinary bladder. The reaction product for ALPase was found on the plasma membrane of all epithelial cells, except the luminal surface of superficial cells. The activity of 5'-Nase appeared on the plasma membrane of all bladder transitional epithelial cells, including the free surface of superficial cells. The Mg-ATPase reaction product was seen on the plasma membrane of superficial, intermediate and basal cells, but never on the luminal surface of superficial cells and it was only occasionally seen on the basal surface. The possible functions of these phosphatases have been discussed, and it was emphasized that the 5'-Nase activity present on the luminal surface of superficial cells may play a special role in the membrane movement of these cells in the transitional epithelium.

The nature and classification of Australian soils affected by sodium

NASA Astrophysics Data System (ADS)

Murphy, Brian; Greene, Richard; Harms, Ben

2017-04-01

Large areas of Australia are affected by the processes of salinity and sodicity and they are important processes to understand as they can result in the degradation of agricultural lands used for both intensive cropping and extensive grazing practices. Sodic soils are defined as those having ESP of at least 6% in Australia. Northcote and Skene (1972) estimated that of Australia's total area of 770 M ha, 39 M ha was affected by salinity and 193-257 M ha by sodicity. However, in a more recent publication, Rengasamy (2006), quoted the areas of saline and sodic soils as 66 M ha and 340 M ha respectively. The soils affected by sodium in Australia include a large group of contrasting soils (Northcote and Skene 1972). Based on the Australian soil classification, included are: • Alkaline strongly sodic to sodic clay soils with uniform texture profiles - largely Vertosols 666 400 km2 • Alkaline strongly sodic to sodic coarse and medium textured soils with uniform and gradational texture profiles - largely Calcarosols 600 700 km2 • Alkaline strongly sodic to sodic texture contrast soils - largely Sodosols 454 400 km2 • Non-alkaline sodic and strongly sodic neutral texture contrast soils - largely Sodosols 134 700 km2 • Non-alkaline sodic acid texture contrast soils - Sodosols and Kurosols 140 700 km2 Many Australian sodic soils have not developed by the traditional solonetz process of leaching of a solonchak, but rather have developed by the accumulation of sodium on the cation exchange complex in preference to the other exchangeable cations without any recognisable intermediate saline phase occurring. This is especially the case for the sodic, non-alkaline texture contrast soils or Sodosols. The major sodic soil group in WRB is the Solonetz soils. These require the presence of a Natric horizon which has to contain illuviated clay and at least 15% ESP. However, there is provision for Sodic qualifiers with at least 6% ESP for many other reference Soil Groups including the Vertisols, Luvisols, Calcisols and Planosols which would have some relationship to Australia's sodic soils.

A Comparative Study: Taxonomic Grouping of Alkaline Protease Producing Bacilli.

PubMed

Tekin, Nilgun; Cihan, Arzu Coleri; Karaca, Basar; Cokmus, Cumhur

2017-03-30

Alkaline proteases have biotechnological importance due to their activity and stability at alkaline pH. 56 bacteria, capable of growing under alkaline conditions were isolated and their alkaline protease activities were carried out at different parameters to determine their optimum alkaline protease production conditions. Seven isolates were showed higher alkaline protease production capacity than the reference strains. The highest alkaline protease producing isolates (103125 U/g), E114 and C265, were identified as Bacillus licheniformis with 99.4% and Bacillus mojavensis 99.8% based on 16S rRNA gene sequence similarities, respectively. Interestingly, the isolates identified as Bacillus safensis were also found to be high alkaline protease producing strains. Genotypic characterizations of the isolates were also determined by using a wide range of molecular techniques (ARDRA, ITS-PCR, (GTG)5-PCR, BOX-PCR). These different techniques allowed us to differentiate the alkaliphilic isolates and the results were in concurrence with phylogenetic analyses of the 16S rRNA genes. While ITS-PCR provided the highest correlation with 16S rRNA groups, (GTG)5-PCR showed the highest differentiation at species and intra-species level. In this study, each of the biotechnologically valuable alkaline protease producing isolates was grouped into their taxonomic positions with multi-genotypic analyses.

Acidity and Alkalinity in mine drainage: Practical considerations

USGS Publications Warehouse

Cravotta, III, Charles A.; Kirby, Carl S.

2004-01-01

In this paper, we emphasize that the Standard Method hot peroxide treatment procedure for acidity determination (hot acidity) directly measures net acidity or net alkalinity, but that more than one water-quality measure can be useful as a measure of the severity of acid mine drainage. We demonstrate that the hot acidity is related to the pH, alkalinity, and dissolved concentrations of Fe, Mn, and Al in fresh mine drainage. We show that the hot acidity accurately indicates the potential for pH to decrease to acidic values after complete oxidation of Fe and Mn, and it indicates the excess alkalinity or that required for neutralization of the sample. We show that the hot acidity method gives consistent, interpretable results on fresh or aged samples. Regional data for mine-drainage quality in Pennsylvania indicated the pH of fresh samples was predominantly acidic (pH 2.5 to 4) or near neutral (pH 6 to 7); approximately 25 percent of the samples had intermediate pH values. This bimodal frequency distribution of pH was distinctive for fully oxidized samples; oxidized samples had acidic or near-neutral pH, only. Samples that had nearneutral pH after oxidation had negative hot acidity; samples that had acidic pH after oxidation had positive hot acidity. Samples with comparable pH values had variable hot acidities owing to variations in their alkalinities and dissolved Fe, Mn, and Al concentrations. The hot acidity was comparable to net acidity computed on the basis of initial pH and concentrations of Fe, Mn, and Al minus the initial alkalinity. Acidity computed from the pH and dissolved metals concentrations, assuming equivalents of 2 per mole of Fe and Mn and 3 per mole of Al, was comparable to that computed on the basis of aqueous species and FeII/FeIII. Despite changes in the pH, alkalinity, and metals concentrations, the hot acidities were comparable for fresh and aged samples. Thus, meaningful “net” acidity can be determined from a measured hot acidity or by calculation from the pH, alkalinity, and dissolved metals concentrations. Together, these water-quality data can be useful for evaluating the potential for toxicity, corrosion, or encrustation and can be helpful for determining the appropriate remediation. By demonstrating the measurements on fresh and aged samples, we hope to encourage (1) consistent use of the hot peroxide treatment procedure for acidity determination and (2) consistent reporting of negative acidity values.

Unravelling the sulphur isotope systematics of an alkaline magmatic province: implications for REE mineralization and exploration

NASA Astrophysics Data System (ADS)

Hutchison, W.; Finch, A.; Boyce, A.; Friis, H.; Borst, A. M.; Horsburgh, N. J.

2017-12-01

Some of the world's best alkaline rare earth element (REE) deposits are formed in magmatic systems that are sealed (i.e., those that are autometasomatised and maintain reducing conditions). Conversely, in open systems where oxidizing fluids infiltrate, it is commonly assumed that REE are redistributed over a wider (less concentrated) zone. Sulphur isotope fractionation is sensitive to variations in temperature and redox, and, although sulphide minerals are relatively abundant in alkaline systems, there have been few attempts to test these hypotheses and develop a sulphur isotope proxy for alkaline metasomatism and formation of associated REE deposits. The Gardar Rift Province in southern Greenland was volcanically active in two periods between 1300 and 1100 Ma and is an ideal natural laboratory to explore sulphur isotope systematics because a near-complete alkaline magmatic lineage is exposed. We present new δ34S from across the province with a particular focus on three alkaline systems (Ilímaussaq, Motzfeldt and Ivigtût) that also host major REE deposits. Primitive mafic rocks from regional Gardar dykes and lavas have a restricted range of δ34S between 0 and 3 ‰ and fractional crystallization imparts no observable change in δ34S. In a few cases high-δ34S rocks (>15 ‰) occur when intrusive units have assimilated local sedimentary crust (δ34S = 25 ‰). Most δ34S variation takes place in the roof zones of alkaline intrusions during late-magmatic and hydrothermal stages, and we identify clear differences between the complexes. At Ilímaussaq, where the magmatic series is exceptionally reduced (below QFM buffer), roof zone δ34S remains narrow (0-3 ‰). At Motzfeldt, a more open oxidizing roof zone (MH buffer), δ34S ranges from -12 ‰ in late-stage fluorite veins to +12 ‰ where local crust has been assimilated. Ivigtût is intermediate between these end-members varying between -5 to +5 ‰. The δ34S variations primarily relate to temperature and redox variations between the systems and highlight important contrasts in roof zone sealing. This work provides new constraints on the varying origins of magmatic fluids in alkaline roof zones, and demonstrates the potential of sulphur isotopes as a redox and temperature proxy. Future work will focus on whether δ34S can be used as an exploration tool to identify REE mineralization at depth.

Strong alkalinization in the anterior midgut of larval yellow fever mosquitoes (Aedes aegypti): involvement of luminal Na+/K+-ATPase.

PubMed

Onken, Horst; Patel, Malay; Javoroncov, Margarita; Izeirovski, Sejmir; Moffett, Stacia B; Moffett, David F

2009-03-01

Recently, Na(+)/K(+)-ATPase has been detected in the luminal membrane of the anterior midgut of larval yellow fever mosquitoes (Aedes aegypti) with immunohistochemical techniques. In this study, the possible involvement of this ATPase in strong alkalinization was investigated on the level of whole larvae, isolated and perfused midgut preparations and on the molecular level of the Na(+)/K(+)-ATPase protein. Ouabain (5 mM) did not inhibit the capability of intact larval mosquitoes to alkalinize their anterior midgut. Also in isolated and perfused midgut preparations the perfusion of the lumen with ouabain (5 mM) did not result in a significant change of the transepithelial voltage or the capacity of luminal alkalinization. Na(+)/K(+)-ATPase activity was completely abolished when KCl was substituted with choline chloride, suggesting that the enzyme cannot act as an ATP-driven Na(+)/H(+)-exchanger. Altogether the results of the present investigation indicate that apical Na(+)/K(+)-ATPase is not of direct importance for strong luminal alkalinization in the anterior midgut of larval yellow fever mosquitoes.

Calcification of in vitro developed hypertrophic cartilage

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tacchetti, C.; Quarto, R.; Campanile, G.

1989-04-01

We have recently reported that dedifferentiated cells derived from stage 28-30 chick embryo tibiae, when transferred in suspension culture in the presence of ascorbic acid, develop in a tissue closely resembling hypertrophic cartilage. Ultrastructural examination of this in vitro formed cartilage showed numerous matrix vesicles associated with the extracellular matrix. In the present article we report that the in vitro developed hypertrophic cartilage undergoes calcification. We indicate a correlation between the levels of alkaline phosphatase activity and calcium deposition at different times of development. Following the transfer of cells into suspension culture and an initial lag phase, the level ofmore » alkaline phosphatase activity rapidly increased. In most experiments the maximum of activity was reached after 5 days of culture. When alkaline phosphatase activity and /sup 45/Ca deposition were measured in the same experiment, we observed that the increase in alkaline phosphatase preceded the deposition of nonwashable calcium deposits in the cartilage.« less

Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory : evaluation of alkaline persulfate digestion as an alternative to Kjeldahl digestion for determination of total and dissolved nitrogen and phosphorus in water

USGS Publications Warehouse

Patton, Charles J.; Kryskalla, Jennifer R.

2003-01-01

Alkaline persulfate digestion was evaluated and validated as a more sensitive, accurate, and less toxic alternative to Kjeldahl digestion for routine determination of nitrogen and phosphorus in surface- and ground-water samples in a large-scale and geographically diverse study conducted by U.S. Geological Survey (USGS) between October 1, 2001, and September 30, 2002. Data for this study were obtained from about 2,100 surface- and ground-water samples that were analyzed for Kjeldahl nitrogen and Kjeldahl phosphorus in the course of routine operations at the USGS National Water Quality Laboratory (NWQL). These samples were analyzed independently for total nitrogen and total phosphorus using an alkaline persulfate digestion method developed by the NWQL Methods Research and Development Program. About half of these samples were collected during nominally high-flow (April-June) conditions and the other half were collected during nominally low-flow (August-September) conditions. The number of filtered and whole-water samples analyzed from each flow regime was about equal.By operational definition, Kjeldahl nitrogen (ammonium + organic nitrogen) and alkaline persulfate digestion total nitrogen (ammonium + nitrite + nitrate + organic nitrogen) are not equivalent. It was necessary, therefore, to reconcile this operational difference by subtracting nitrate + nitrite concentra-tions from alkaline persulfate dissolved and total nitrogen concentrations prior to graphical and statistical comparisons with dissolved and total Kjeldahl nitrogen concentrations. On the basis of two-population paired t-test statistics, the means of all nitrate-corrected alkaline persulfate nitrogen and Kjeldahl nitrogen concentrations (2,066 paired results) were significantly different from zero at the p = 0.05 level. Statistically, the means of Kjeldahl nitrogen concentrations were greater than those of nitrate-corrected alkaline persulfate nitrogen concentrations. Experimental evidence strongly suggests, however, that this apparent low bias resulted from nitrate interference in the Kjeldahl digestion method rather than low nitrogen recovery by the alkaline persulfate digestion method. Typically, differences between means of Kjeldahl nitrogen and nitrate-corrected alkaline persulfate nitrogen in low-nitrate concentration (< 0.1 milligram nitrate nitrogen per liter) subsets of filtered surface- and ground-water samples were statistically equivalent to zero at the p =level.Paired analytical results for dissolved and total phosphorus in Kjeldahl and alkaline persulfate digests were directly comparable because both digestion methods convert all forms of phosphorus in water samples to orthophosphate. On the basis of two-population paired t-test statistics, the means of all Kjeldahl phosphorus and alkaline persulfate phosphorus concentrations (2,093 paired results) were not significantly different from zero at the p = 0.05 level. For some subsets of these data, which were grouped according to water type and flow conditions at the time of sample collection, differences between means of Kjeldahl phosphorus and alkaline persulfate phosphorus concentrations were not equivalent to zero at the p = 0.05 level. Differences between means of these subsets, however, were less than the method detection limit for phosphorus (0.007 milligram phosphorus per liter) by the alkaline persulfate digestion method, and were therefore analytically insignificant.This report provides details of the alkaline persulfate digestion procedure, interference studies, recovery of various nitrogen- and phosphorus-containing compounds, and other analytical figures of merit. The automated air-segmented continuous flow methods developed to determine nitrate and orthophosphate in the alkaline persulfate digests also are described. About 125 microliters of digested sample are required to determine nitrogen and phosphorus in parallel at a rate of about 100 samples per hour with less than 1-percent sample in

Preparation of fatty acid methyl esters for gas-chromatographic analysis of marine lipids: insight studies.

PubMed

Carvalho, Ana P; Malcata, F Xavier

2005-06-29

Assays for fatty acid composition in biological materials are commonly carried out by gas chromatography, after conversion of the lipid material into the corresponding methyl esters (FAME) via suitable derivatization reactions. Quantitative derivatization depends on the type of catalyst and processing conditions employed, as well as the solubility of said sample in the reaction medium. Most literature pertinent to derivatization has focused on differential comparison between alternative methods; although useful to find out the best method for a particular sample, additional studies on factors that may affect each step of FAME preparation are urged. In this work, the influence of various parameters in each step of derivatization reactions was studied, using both cod liver oil and microalgal biomass as model systems. The accuracies of said methodologies were tested via comparison with the AOCS standard method, whereas their reproducibility was assessed by analysis of variance of (replicated) data. Alkaline catalysts generated lower levels of long-chain unsaturated FAME than acidic ones. Among these, acetyl chloride and BF(3) were statistically equivalent to each other. The standard method, which involves alkaline treatment of samples before acidic methylation with BF(3), provided equivalent results when compared with acidic methylation with BF(3) alone. Polarity of the reaction medium was found to be of the utmost importance in the process: intermediate values of polarity [e.g., obtained by a 1:1 (v/v) mixture of methanol with diethyl ether or toluene] provided amounts of extracted polyunsaturated fatty acids statistically higher than those obtained via the standard method.

Mineralogy and sedimentology of the Miocene Göcenoluk borate deposit, Kırka district, western Anatolia, Turkey

NASA Astrophysics Data System (ADS)

García-Veigas, Javier; Helvacı, Cahit

2013-05-01

The Miocene boratiferous district of Kırka, in western Anatolia (Turkey), is the most important Na-borate (borax) resource in the world. Two separate deposits in the Kırka district are located near the villages of Sarıkaya and Göcenoluk (Eskişehir Province). Borax is intensively exploited in open-pit mines in the Sarıkaya deposit while only small quarries of colemanite are known in the Göcenoluk deposit. Recent exploratory drilling in the Göcenoluk area intersected a thick succession of dolostones, tuffs and three borate-bearing units (Lower, Intermediate and Upper Borate Units). In them, the most abundant borate mineral is ulexite (Ca-Na-borate) passing at depth to probertite. Borax (Na-borate) is only present in the Intermediate Borate Unit. Minor amounts of colemanite (Ca-borate) and hydroboracite (Ca-Mg-borate) occur at the base, and/or top, of each mineralized unit. Pyroclastic layers within the borate units show intense alteration by alkaline, boron-bearing waters and formation of diagenetic clay minerals (smectites), zeolites (analcime) and borosilicates (searlesite). The Göcenoluk succession is interpreted as a shallow, ephemeral, alkaline lake deposit in which carbonates formed as stromatolites and travertines. Borate precipitation in the Göcenoluk area took place interstitially within muddy and carbonate sediments in a lateral progression from marginal Ca-borates towards Na-Ca-borates and rarely to Na-borates in the center of the lake. Authigenic silicate mineral distribution shows parallel changes toward the center of the lake that reflect increasing pH gradient.

Arginine Coordination in Enzymatic Phosphoryl Transfer: Evaluation of the Effect of Arg166 Mutations in Escherichia Coli Alkaline Phosphatase

DOE Office of Scientific and Technical Information (OSTI.GOV)

O'Brien, P.J.; Lassila, J.K.; Fenn, T.D.

2009-05-22

Arginine residues are commonly found in the active sites of enzymes catalyzing phosphoryl transfer reactions. Numerous site-directed mutagenesis experiments establish the importance of these residues for efficient catalysis, but their role in catalysis is not clear. To examine the role of arginine residues in the phosphoryl transfer reaction, we have measured the consequences of mutations to arginine 166 in Escherichia coli alkaline phosphatase on hydrolysis of ethyl phosphate, on individual reaction steps in the hydrolysis of the covalent enzyme-phosphoryl intermediate, and on thio substitution effects. The results show that the role of the arginine side chain extends beyond its positivemore » charge, as the Arg166Lys mutant is as compromised in activity as Arg166Ser. Through measurement of individual reaction steps, we construct a free energy profile for the hydrolysis of the enzyme-phosphate intermediate. This analysis indicates that the arginine side chain strengthens binding by {approx}3 kcal/mol and provides an additional 1-2 kcal/mol stabilization of the chemical transition state. A 2.1 {angstrom} X-ray diffraction structure of Arg166Ser AP is presented, which shows little difference in enzyme structure compared to the wild-type enzyme but shows a significant reorientation of the bound phosphate. Altogether, these results support a model in which the arginine contributes to catalysis through binding interactions and through additional transition state stabilization that may arise from complementarity of the guanidinum group to the geometry of the trigonal bipyramidal transition state.« less

Ba, B, and U element partitioning in magnesian calcite skeletons of Octocorallia corals

NASA Astrophysics Data System (ADS)

Yoshimura, T.; Suzuki, A.; Iwasaki, N.

2015-01-01

Barium, boron and uranium element partitioning and oxygen and carbon isotope fractionation of high-Mg calcite skeletons of Octocorallia corals were investigated. The dissolved Ba concentration in seawater and the coral Ba/Ca ratio showed a clear positive correlation. The empirically derived barium partition coefficient is comparable to previous data for not only calcitic corals but also intermediate- to deep-water-dwelling scleractinian corals whose skeletons are composed of aragonite. Octocorallia corals are geologically important producers of biominerals, and they provide long-term records (up to hundreds of years) of environmental conditions in the deep ocean. Our data suggest that Ba/Ca ratios in Octocorallia corals may be a useful proxy for nutrients in intermediate and deep waters. The Ba/Ca ratio, a possible proxy for pH or carbonate ion concentration in seawater, showed the largest correlation with δ13C among the examined parameters. This result implies that the pH of the extracytoplasmic calcifying fluid (ECF) simultaneously influences δ18O, δ13C, and Ba/Ca by influencing the relative contributions of dissolved carbon sources in the ECF. Positive correlations of Ba/Ca with δ18 and δ13C suggest that δ18 and δ13C are enriched in light isotopes when conditions are less alkaline, suggesting a potential role of biological alkalinity pumping becomes more favorable with decreasing calcifying fluid pH. Substantial inter- and intra-specimen variations in Ba/Ca suggest that physicochemical factors do not exert a dominant systematic control on U incorporation.

Efficacy of Alkali-treated Sugarcane Fiber for Improving Physicochemical and Textural Properties of Meat Emulsions with Different Fat Levels

PubMed Central

Kim, Hyun-Wook; Setyabrata, Derico; Lee, Yong-Jae; Brad Kim, Yuan H.

2018-01-01

Abstract The objective of this study was to evaluate the efficacy of alkaline-treated sugarcane bagasse fiber on physicochemical and textural properties of meat emulsion with different fat levels. Crude sugarcane bagasse fiber (CSF) was treated with calcium hydroxide (Ca(OH2)) to obtain alkaline-treated sugarcane bagasse fiber (ASF). The two types of sugarcane bagasse fiber (CSF and ASF) were incorporated at 2% levels in pork meat emulsions prepared with 5%, 10% and 20% fat levels. Alkaline-treatment markedly increased acid detergent fiber content (p=0.002), but significantly decreased protein, fat, ash and other carbohydrate contents. ASF exhibited significantly higher water-binding capacity, but lower oil-binding and emulsifying capacities than CSF. Meat emulsions formulated with 10% fat and 2% sugarcane bagasse fiber had equivalent cooking loss and textural properties to control meat emulsion (20% fat without sugarcane bagasse fiber). The two types of sugarcane bagasse fiber had similar impacts on proximate composition, cooking yield and texture of meat emulsion at the same fat level, respectively (p>0.05). Our results confirm that sugarcane bagasse fiber could be a functional food ingredient for improving physicochemical and textural properties of meat emulsion, at 2% addition level. Further, the altered functional properties of alkaline-treated sugarcane bagasse fiber had no impacts on physicochemical and textural properties of meat emulsions, regardless of fat level at 5%, 10% and 20%. PMID:29805281

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Shizhong; White, Michael G.; Liu, Ping

Here, we report a detailed mechanistic study of the oxygen reduction reaction (ORR) on Pt(111) in alkaline solution, combining density functional theory and kinetic Monte Carlo simulations. A complex reaction network including four possible pathways via either 2e – or 4e – transfer is established and is able to reproduce the experimental measured polarization curve at both low- and high-potential regions. Our results show that it is essential to account for solvation by water and the dynamic coverage of *OH to describe the reaction kinetics well. In addition, a chemisorbed water (*H 2O)-mediated mechanism including 4e – transfers is identified,more » where the reduction steps via *H 2O on the surface are potential-independent and only the final removal of *OH from the surface in the form of OH –(aq) contributes to the current. For the ORR in alkaline solutions, such a mechanism is more competitive than the associative and dissociative mechanisms typically used to describe the ORR in acid solution. Finally, *OH and **O 2 intermediates are found to be critically important for tuning the ORR activity of Pt in alkaline solution. To enhance the activity, the binding of Pt should be tuned in such a way that *OH binding is weak enough to release more surface sites under working conditions, while **O 2 binding is strong enough to enable the ORR via the 4e – transfer mechanism.« less

Derivation of intermediate to silicic magma from the basalt analyzed at the Vega 2 landing site, Venus.

PubMed

Shellnutt, J Gregory

2018-01-01

Geochemical modeling using the basalt composition analyzed at the Vega 2 landing site indicates that intermediate to silicic liquids can be generated by fractional crystallization and equilibrium partial melting. Fractional crystallization modeling using variable pressures (0.01 GPa to 0.5 GPa) and relative oxidation states (FMQ 0 and FMQ -1) of either a wet (H2O = 0.5 wt%) or dry (H2O = 0 wt%) parental magma can yield silicic (SiO2 > 60 wt%) compositions that are similar to terrestrial ferroan rhyolite. Hydrous (H2O = 0.5 wt%) partial melting can yield intermediate (trachyandesite to andesite) to silicic (trachydacite) compositions at all pressures but requires relatively high temperatures (≥ 950°C) to generate the initial melt at intermediate to low pressure whereas at high pressure (0.5 GPa) the first melts will be generated at much lower temperatures (< 800°C). Anhydrous partial melt modeling yielded mafic (basaltic andesite) and alkaline compositions (trachybasalt) but the temperature required to produce the first liquid is very high (≥ 1130°C). Consequently, anhydrous partial melting is an unlikely process to generate derivative liquids. The modeling results indicate that, under certain conditions, the Vega 2 composition can generate silicic liquids that produce granitic and rhyolitic rocks. The implication is that silicic igneous rocks may form a small but important component of the northeast Aphrodite Terra.

Derivation of intermediate to silicic magma from the basalt analyzed at the Vega 2 landing site, Venus

PubMed Central

2018-01-01

Geochemical modeling using the basalt composition analyzed at the Vega 2 landing site indicates that intermediate to silicic liquids can be generated by fractional crystallization and equilibrium partial melting. Fractional crystallization modeling using variable pressures (0.01 GPa to 0.5 GPa) and relative oxidation states (FMQ 0 and FMQ -1) of either a wet (H2O = 0.5 wt%) or dry (H2O = 0 wt%) parental magma can yield silicic (SiO2 > 60 wt%) compositions that are similar to terrestrial ferroan rhyolite. Hydrous (H2O = 0.5 wt%) partial melting can yield intermediate (trachyandesite to andesite) to silicic (trachydacite) compositions at all pressures but requires relatively high temperatures (≥ 950°C) to generate the initial melt at intermediate to low pressure whereas at high pressure (0.5 GPa) the first melts will be generated at much lower temperatures (< 800°C). Anhydrous partial melt modeling yielded mafic (basaltic andesite) and alkaline compositions (trachybasalt) but the temperature required to produce the first liquid is very high (≥ 1130°C). Consequently, anhydrous partial melting is an unlikely process to generate derivative liquids. The modeling results indicate that, under certain conditions, the Vega 2 composition can generate silicic liquids that produce granitic and rhyolitic rocks. The implication is that silicic igneous rocks may form a small but important component of the northeast Aphrodite Terra. PMID:29584745

Genesis of post-collisional calc-alkaline and alkaline granitoids in Qiman Tagh, East Kunlun, China

NASA Astrophysics Data System (ADS)

Yu, Miao; Feng, Chengyou; Zhao, Yiming; Li, Daxin

2015-12-01

The post-collisional magmatism of Qiman Tagh is characterized by the intrusion of voluminous intermediate to felsic granitoids, including syenogranite, monzogranite, granodiorite, tonalite and diorite. The granitoids can be divided into two magmatic suites: Calc-alkaline (CA) and alkaline (Alk), which were emplaced from ~ 236 Ma to ~ 204 Ma. The CA suite contains metaluminous granodiorites and monzogranites. Typical Qiman Tagh CA granodiorites show moderately fractionated REE patterns ((La/Yb)N = 4.35-25.11) with significant negative Eu anomalies (Eu/Eu* = 0.54-1.34), and the primitive mantle-normalized spidergrams show strong depletion of Nb and Sr. The Qiman Tagh CA monzogranites show similar fractionated REE patterns ((La/Yb)N = 2.70-13.5) with less prominent negative Eu anomalies, and the chondrite-normalized spidergrams show strongly depleted Ba, Nb and Sr. The Alk suite, including syenogranite, is highly potassic (K2O/Na2O = 1.09-3.56) and peraluminous (A/CNK = 0.91-1.06). Compared to typical Qiman Tagh CA granodiorites, the Qiman Tagh Alk granitoids can be distinguished by their higher Rb, Nb, Ga/Al, FeO*/MgO, Y/Sr and Rb/Sr, as well as their lower Mg#, MgO, CaO, Al2O3, Sr, Co, V, Eu/Eu*, Ba/Nb, La/Nb, Ba/La and Ce/Nb. The Qiman Tagh CA rocks were most likely to be derived from the partial melting of garnet-amphibolite-facies rocks in the lower crust, leaving behind anhydrous granulite-facies rocks with plagioclase and garnet in the residue. The Alk rocks may have formed by the continued partial melting of granulite-facies rocks at elevated temperatures (> 830 °C).

Geochemistry of primary-carbonate bearing K-rich igneous rocks in the Awulale Mountains, western Tianshan: Implications for carbon-recycling in subduction zone

NASA Astrophysics Data System (ADS)

Yang, Wu-Bin; Niu, He-Cai; Shan, Qiang; Chen, Hua-Yong; Hollings, Pete; Li, Ning-Bo; Yan, Shuang; Zartman, Robert E.

2014-10-01

Arc magmatism plays an important role in the recycling of subducted carbon and returning it to the surface. However, the transfer mechanisms of carbon are poorly understood. In this study, the contribution of subducted carbonate-rich sediments to the genesis of the carbonate-bearing K-rich igneous rocks from western Tianshan was investigated. Four key triggers are involved, including sediments subduction, slab decarbonation, partial melting and magma segregation. The globular carbonate ocelli show C-O isotope signatures intermediate between oceanic sediments and mantle, suggesting that the carbon of the primary carbonate ocelli was derived from recycled subducted sediments in the mantle. Decarbonation of the subducted slab is regarded as the primary agent to carbonize the mantle wedge. Geochemical features indicate that the carbonate ocelli are primary, and that the parental K- and carbon-rich mafic alkaline magma was derived from partial melting of carbonated mantle wedge veined with phlogopite. Major and trace element compositions indicate that globular carbonate ocelli hosted in the Bugula K-rich igneous rocks are calcio-carbonate and formed primarily by segregation of the differentiated CO2-rich alkaline magma after crystallization fractionation. The K-rich alkaline magma, which formed from partial melting of metasomatized (i.e., phlogopite bearing) mantle wedge in the sub-arc region, is a favorable agent to transport subducted carbon back to the Earth's surface during carbon recycling in subduction zones, because of the high CO2 solubility in alkaline mafic magma. We therefore propose a model for the petrogenesis of the carbonate-bearing K-rich igneous rocks in western Tianshan, which are significant for revealing the mechanism of carbon recycling in subduction zones.

Novel inorganic materials for polymer electrolyte and alkaline fuel cells

NASA Astrophysics Data System (ADS)

Tadanaga, Kiyoharu

2012-06-01

Inorganic materials with high ionic conductivity must have big advantages for the thermal and long term stability when the materials are used as the electrolyte of fuel cells. In the present paper, novel ionic conductive inorganic materials for polymer electrolyte fuel cells (PEFCs) and all solid state alkaline fuel cells (AFCs) that have been developed by our group have been reviewed. PEFCs which can operate in temperature range from 100 to 200 °C are intensively studied because of some advantages such as reduction of CO poisoning of Pt catalyst and acceleration of electrode reactions. We showed that the fuel cells using the composite membranes prepared from phosphosilicate gel powder and polyimide precursor can operate in the temperature range from 30 to 180 °C. We also found that the inorganic-organic hybrid membranes with acid-base pairs from 3-aminopropyl triethoxy silane and H2SO4 or H3PO4 show high proton conductivity under dry atmosphere, and the membranes are thermally stable at intermediate temperatures. On the other hand, because the use of noble platinum is the serious problem for the commercialization of PEFCs and because oxidation reactions are usually faster than those of acid-type fuel cells, alkaline type fuel cells, in which a nonplatinum catalyst can be used, are attractive. Recently, we have proposed an alkaline-type direct ethanol fuel cell (DEFC) using a natural clay electrolyte with non-platinum catalysts. So-called hydrotalcite clay, Mg-Al layered double hydroxide intercalated with CO32- (Mg-Al CO32- LDH), has been proved to be a hydroxide ion conductor. An alkalinetype DEFC using Mg-Al CO32- LDH as the electrolyte and aqueous solution of ethanol and potassium hydroxide as a source of fuel exhibited excellent electrochemical performance.

Contemporaneous alkaline and calc-alkaline series in Central Anatolia (Turkey): Spatio-temporal evolution of a post-collisional Quaternary basaltic volcanism

NASA Astrophysics Data System (ADS)

Dogan-Kulahci, Gullu Deniz; Temel, Abidin; Gourgaud, Alain; Varol, Elif; Guillou, Hervé; Deniel, Catherine

2018-05-01

This study focuses on spatio-temporal evolution of basaltic volcanism in the Central Anatolian post-collisional Quaternary magmatic province which developed along a NE-SW orientation in Turkey. This magmatic province consists of the stratovolcanoes Erciyes (ES) and Hasandag (HS), and the basaltic volcanic fields of Obruk-Zengen (OZ) and Karapınar (KA). The investigated samples range between basic to intermediate in composition (48-56 wt% SiO2), and exhibit calc-alkaline affinity at ES whereas HS, OZ and KA are alkaline in composition. Based on new Ksbnd Ar ages and major element data, the oldest basaltic rock of ES is 1700 ± 40 ka old and exhibits alkaline character, whereas the youngest basaltic trachyandesite is 12 ± 5 ka old and calc-alkaline in composition. Most ES basaltic rocks are younger than 350 ka. All samples dated from HS are alkaline basalts, ranging from 543 ± 12 ka to 2 ± 7 ka old. With the exception of one basalt, all HS basalts are 100 ka or younger in age. Ksbnd Ar ages range from 797 ± 20 ka to 66 ± 7 ka from OZ. All the basalt samples are alkaline in character and are older than the HS alkaline basalts, with the exception of the youngest samples. The oldest and youngest basaltic samples from KA are 280 ± 7 ka and 163 ± 10 ka, respectively, and are calc-alkaline in character. Based on thermobarometric estimates samples from OZ exhibit the highest cpx-liqidus temperature and pressure. For all centers the calculated crystallization depths are between 11 and 28 km and increase from NE to SW. Multistage crystallization in magma chamber(s) located at different depths can explain this range in pressure. Harker variation diagrams coupled with least-squares mass balance calculations support fractional crystallization for ES and, to lesser extend for HS, OZ and KA. All basaltic volcanic rocks of this study are enriched in large-ion lithophile elements (LILE) and light rare earth elements (LREE). The lack of negative anomalies for high field strength elements (HFSE; Y, Yb) and the La/Nb >1 favor a shallow lithospheric source for ES, HS, OZ and KA basaltic volcanic rocks, whereas some samples bear the trace element signature of an asthenospheric mantle source. The lithospheric mantle beneath Central Anatolia may have not been affected from asthenospheric mantle directly. Negative Nb-Ta-Ti anomalies and a positive Pb spike of ES, HS, OZ and KA may be ascribed to crustal contamination or as the imprints of the previous subduction processes. According to this study, and previous studies, the effect of subduction and/or crustal contamination in Central Anatolia decreased from the Miocene to the Quaternary, and the origin of the Quaternary basaltic rocks mainly derived from subduction-related magmas enriched with sediment input rather than to slab-derived fluids. Our calculated eruption ages for the four basaltic complexes show that spatial differences predominate, whereas temporal trends are difficult to discern due to limited age resolution. According to the available geochronological, petrological and geochemical data, alkaline and calc-alkaline volcanism occurred simultaneously from distinct parental magmas.

Dynamic response of C-type natriuretic peptide and its aminoterminal propeptide (NTproCNP) to growth hormone treatment in children with short stature.

PubMed

Olney, Robert C; Salehi, Parisa; Prickett, Timothy C R; Lima, John J; Espiner, Eric A; Sikes, Kaitlin M; Geffner, Mitchell E

2016-10-01

C-type natriuretic peptide (CNP) and its aminoterminal propeptide (NTproCNP) are potential biomarkers of recombinant human growth hormone (rhGH) efficacy. The objective of this study was to describe the pharmacodynamics of plasma CNP and NTproCNP levels in response to rhGH treatment and to identify the optimal time of sampling after starting rhGH. This was a prospective, observational study. Subjects were treated with rhGH for 1 year, with blood sampled at regular intervals. Eighteen prepubertal children, eight with low levels of GH on biochemical testing and ten with idiopathic short stature, completed the study. Blood levels of CNP, NTproCNP, GH, insulin-like growth factor-I, leptin and bone-specific alkaline phosphatase were measured. Anthropometrics were obtained. Plasma levels of both CNP and NTproCNP reached peak levels 7-28 days after starting rhGH treatment and then declined to intermediate levels through the first year. Plasma NTproCNP levels after 14 days trended towards a correlation with height velocity after 6 and 12 months of treatment. Unexpectedly, serum GH levels measured 2 and 28 days after starting rhGH correlated strongly with height velocity after 6 and 12 months of treatment. This study identified 14 days after starting rhGH treatment as the optimal time for assessing CNP and NTproCNP levels as biomarkers of rhGH efficacy. Additionally, we identified GH levels as a potential biomarker. Larger, prospective studies are now needed to test the clinical utility of these biomarkers. © 2016 John Wiley & Sons Ltd.

Primary battery design and safety guidelines handbook

NASA Technical Reports Server (NTRS)

Bragg, Bobby J.; Casey, John E.; Trout, J. Barry

1994-01-01

This handbook provides engineers and safety personnel with guidelines for the safe design or selection and use of primary batteries in spaceflight programs. Types of primary batteries described are silver oxide zinc alkaline, carbon-zinc, zinc-air alkaline, manganese dioxide-zionc alkaline, mercuric oxide-zinc alkaline, and lithium anode cells. Along with typical applications, the discussions of the individual battery types include electrochemistry, construction, capacities and configurations, and appropriate safety measures. A chapter on general battery safety covers hazard sources and controls applicable to all battery types. Guidelines are given for qualification and acceptance testing that should precede space applications. Permissible failure levels for NASA applications are discussed.

Alkaline phosphatase activity after cardiothoracic surgery in infants and correlation with post-operative support and inflammation: a prospective cohort study.

PubMed

Davidson, Jesse; Tong, Suhong; Hauck, Amanda; Lawson, D Scott; Jaggers, James; Kaufman, Jon; da Cruz, Eduardo

2012-08-20

Limited evidence suggests that serum alkaline phosphatase activity may decrease after cardiac surgery in adults and children. The importance of this finding is not known. Recent studies, however, have identified a potential role for alkaline phosphatase as modulator of inflammation in multiple settings, including during adult cardiopulmonary bypass. We sought to describe the change in alkaline phosphatase activity after cardiothoracic surgery in infants and to assess for a correlation with intensity and duration of post-operative support, markers of inflammation, and short-term clinical outcomes. Sub-analysis of a prospective observational study on the kinetics of procalcitonin in 70 infants (≤ 90 days old) undergoing cardiothoracic surgery. Subjects were grouped based on the use of cardiopulmonary bypass and delayed sternal closure. Alkaline phosphatase, procalcitonin, and C-reactive protein (CRP) levels were obtained pre-operation and on post-operative day 1. Mean change in alkaline phosphatase activity was determined in each surgical group. Generalized linear modeling and logistic regression were employed to assess for associations between post-operative alkaline phosphatase activity and post-operative support, inflammation, and short term outcomes. Primary endpoints were vasoactive-inotropic score at 24 hours and length of intubation. Secondary endpoints included procalcitonin/CRP levels on post-operative day 1, length of hospital stay, and cardiac arrest or death. Mean decrease in alkaline phosphatase was 30 U/L (p = 0.01) in the non-bypass group, 114 U/L (p < 0.0001) in the bypass group, and 94 U/L (p < 0.0001) in the delayed sternal closure group. On multivariate analysis, each 10 U/L decrease in alkaline phosphatase activity on post-operative day 1 was independently associated with an increase in vasoactive-inotropic score by 0.7 (p < 0.0001), intubation time by 6% (p < 0.05), hospital stay by 5% (p < 0.05), and procalcitonin by 14% (P < 0.01), with a trend towards increased odds of cardiac arrest or death (OR 1.3; p = 0.06). Post-operative alkaline phosphatase activity was not associated with CRP (p = 0.7). Alkaline phosphatase activity decreases after cardiothoracic surgery in infants. Low post-operative alkaline phosphatase activity is independently associated with increased procalcitonin, increased vasoactive/inotropic support, prolonged intubation time, and prolonged hospital stay. Alkaline phosphatase may serve as a biomarker and potential modulator of post-operative support and inflammation following cardiothoracic surgery in infants.

Alkaline phosphatase activity after cardiothoracic surgery in infants and correlation with post-operative support and inflammation: a prospective cohort study

PubMed Central

2012-01-01

Introduction Limited evidence suggests that serum alkaline phosphatase activity may decrease after cardiac surgery in adults and children. The importance of this finding is not known. Recent studies, however, have identified a potential role for alkaline phosphatase as modulator of inflammation in multiple settings, including during adult cardiopulmonary bypass. We sought to describe the change in alkaline phosphatase activity after cardiothoracic surgery in infants and to assess for a correlation with intensity and duration of post-operative support, markers of inflammation, and short-term clinical outcomes. Methods Sub-analysis of a prospective observational study on the kinetics of procalcitonin in 70 infants (≤90 days old) undergoing cardiothoracic surgery. Subjects were grouped based on the use of cardiopulmonary bypass and delayed sternal closure. Alkaline phosphatase, procalcitonin, and C-reactive protein (CRP) levels were obtained pre-operation and on post-operative day 1. Mean change in alkaline phosphatase activity was determined in each surgical group. Generalized linear modeling and logistic regression were employed to assess for associations between post-operative alkaline phosphatase activity and post-operative support, inflammation, and short term outcomes. Primary endpoints were vasoactive-inotropic score at 24 hours and length of intubation. Secondary endpoints included procalcitonin/CRP levels on post-operative day 1, length of hospital stay, and cardiac arrest or death. Results Mean decrease in alkaline phosphatase was 30 U/L (p = 0.01) in the non-bypass group, 114 U/L (p<0.0001) in the bypass group, and 94 U/L (p<0.0001) in the delayed sternal closure group. On multivariate analysis, each 10 U/L decrease in alkaline phosphatase activity on post-operative day 1 was independently associated with an increase in vasoactive-inotropic score by 0.7 (p<0.0001), intubation time by 6% (p<0.05), hospital stay by 5% (p<0.05), and procalcitonin by 14% (P<0.01), with a trend towards increased odds of cardiac arrest or death (OR 1.3; p = 0.06). Post-operative alkaline phosphatase activity was not associated with CRP (p = 0.7). Conclusions Alkaline phosphatase activity decreases after cardiothoracic surgery in infants. Low post-operative alkaline phosphatase activity is independently associated with increased procalcitonin, increased vasoactive/inotropic support, prolonged intubation time, and prolonged hospital stay. Alkaline phosphatase may serve as a biomarker and potential modulator of post-operative support and inflammation following cardiothoracic surgery in infants. PMID:22906145

Silicon Priming Created an Enhanced Tolerance in Alfalfa (Medicago sativa L.) Seedlings in Response to High Alkaline Stress.

PubMed

Liu, Duo; Liu, Miao; Liu, Xiao-Long; Cheng, Xian-Guo; Liang, Zheng-Wei

2018-01-01

Alkaline stress as a result of higher pH usually triggers more severe physiological damage to plants than that of saline stress with a neutral pH. In the present study, we demonstrated that silicon (Si) priming of alfalfa ( Medicago sativa L.) seedlings increased their tolerance to high alkaline stress situations. Gongnong No. 1 seedlings were subjected to alkaline stress simulated by 25 mM Na 2 CO 3 (pH 11.2). Alkaline stress greatly decreased the biomass and caused severe lodging or wilting of alfalfa seedlings. In contrast, the application of Si to alfalfa seedlings 36 h prior to the alkaline treatment significantly alleviated the damage symptoms and greatly increased the biomass and chlorophyll content. Because of being concomitant with increasing photosynthesis and water use efficiency, decreasing membrane injury and malondialdehyde content, and increasing peroxidase and catalase ascorbate activities in alfalfa leaves, thereby alleviating the triggered oxidative damage by alkaline stress to the plant. Furthermore, Si priming significantly decreased the accumulation of protein and proline content in alfalfa, thus reducing photosynthetic feedback repression. Si priming significantly accumulated more Na in the roots, but led to a decrease of Na accumulation and an increase of K accumulation in the leaves under alkaline stress. Meanwhile, Si priming decreased the accumulation of metal ions such as Mg, Fe, Mn, and Zn in the roots of alfalfa seedlings under alkaline stress. Collectively, these results suggested that Si is involved in the metabolic or physiological changes and has a potent priming effect on the alkaline tolerance of alfalfa seedlings. The present study indicated that Si priming is a new approach to improve the alkaline tolerance in alfalfa and provides increasing information for further exploration of the alkaline stress response at the molecular level in alfalfa.

Approach of describing dynamic production of volatile fatty acids from sludge alkaline fermentation.

PubMed

Wang, Dongbo; Liu, Yiwen; Ngo, Huu Hao; Zhang, Chang; Yang, Qi; Peng, Lai; He, Dandan; Zeng, Guangming; Li, Xiaoming; Ni, Bing-Jie

2017-08-01

In this work, a mathematical model was developed to describe the dynamics of fermentation products in sludge alkaline fermentation systems for the first time. In this model, the impacts of alkaline fermentation on sludge disintegration, hydrolysis, acidogenesis, acetogenesis, and methanogenesis processes are specifically considered for describing the high-level formation of fermentation products. The model proposed successfully reproduced the experimental data obtained from five independent sludge alkaline fermentation studies. The modeling results showed that alkaline fermentation largely facilitated the disintegration, acidogenesis, and acetogenesis processes and severely inhibited methanogenesis process. With the pH increase from 7.0 to 10.0, the disintegration, acidogenesis, and acetogenesis processes respectively increased by 53%, 1030%, and 30% while methane production decreased by 3800%. However, no substantial effect on hydrolysis process was found. The model also indicated that the pathway of acetoclastic methanogenesis was more severely inhibited by alkaline condition than that of hydrogentrophic methanogenesis. Copyright © 2017 Elsevier Ltd. All rights reserved.

Tetraethylene glycol promoted two-step, one-pot rapid synthesis of indole-3-[1- 11C]acetic acid

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Sojeong; Qu, Wenchao; Alexoff, David L.

2014-12-12

An operationally friendly, two-step, one-pot process has been developed for the rapid synthesis of carbon-11 labeled indole-3-acetic acid ([ 11]IAA or [ 11]auxin). By replacing an aprotic polar solvent with tetraethylene glycol, nucleophilic [ 11]cyanation and alkaline hydrolysis reactions were performed consecutively in a single pot without a time-consuming intermediate purification step. The entire production time for this updated procedure is 55 min, which dramatically simplifies the entire synthesis and reduces the starting radioactivity required for a whole plant imaging study.

Hydrodehalogenation of alkyl iodides with base-mediated hydrogenation and catalytic transfer hydrogenation: application to the asymmetric synthesis of N-protected α-methylamines.

PubMed

Mandal, Pijus K; Birtwistle, J Sanderson; McMurray, John S

2014-09-05

We report a very mild synthesis of N-protected α-methylamines from the corresponding amino acids. Carboxyl groups of amino acids are reduced to iodomethyl groups via hydroxymethyl intermediates. Reductive deiodination to methyl groups is achieved by hydrogenation or catalytic transfer hydrogenation under alkaline conditions. Basic hydrodehalogenation is selective for the iodomethyl group over hydrogenolysis-labile protecting groups, such as benzyloxycarbonyl, benzyl ester, benzyl ether, and 9-fluorenyloxymethyl, thus allowing the conversion of virtually any protected amino acid into the corresponding N-protected α-methylamine.

Hydrodehalogenation of Alkyl Iodides with Base-Mediated Hydrogenation and Catalytic Transfer Hydrogenation: Application to the Asymmetric Synthesis of N-Protected α-Methylamines

PubMed Central

2015-01-01

We report a very mild synthesis of N-protected α-methylamines from the corresponding amino acids. Carboxyl groups of amino acids are reduced to iodomethyl groups via hydroxymethyl intermediates. Reductive deiodination to methyl groups is achieved by hydrogenation or catalytic transfer hydrogenation under alkaline conditions. Basic hydrodehalogenation is selective for the iodomethyl group over hydrogenolysis-labile protecting groups, such as benzyloxycarbonyl, benzyl ester, benzyl ether, and 9-fluorenyloxymethyl, thus allowing the conversion of virtually any protected amino acid into the corresponding N-protected α-methylamine. PMID:25116734

Alkaline Plume in the Aptian Sand Aquifer in the Context of Low-Level Radioactive Waste Surface Disposal

NASA Astrophysics Data System (ADS)

Cochepin, B.; Munier, I.; MADE, B.

2017-12-01

The storage vaults for low and intermediate-level short-lived radioactive waste in the East of France are settled on the Aptian sand layer. In the context of the periodic examination by the nuclear regulators, it has been recommended to assess more precisely the chemical conditions for a potential release of radionuclides in the underlying water table. In particular, this study aims at assessing the eventuality of spreading an alkaline plume in the Aptian sand pore water by the chemical degradation of the vault cementitious materials. The numerical approach developed for this purpose is supported by both experimental characterizations of tracers in the water table and results from preliminary numerical studies on the hydrology of the site and the hydraulic evolution of the storage. The results from these specific simulations were simplified in the reactive transport model to focus on the mechanistic description of the chemical processes taking place in the waste and vaults and on their consequences on the underlying water table. During the operating period of the disposal, the reactive transport modelling shows that the low water saturation in the vaults material and in the vadose zone prevents the aquifer from a significant increase of the water pH under the cement-based vaults. These results are in reasonable agreement with the pH regularly measured in the underlying water table. After storage closure, during the few hundred years of the monitoring period and furthermore beyond, the reactive transport modelling shows a noticeable release of hydroxyls and alkali ions under the disposal vaults and their spread downstream the storage site leading to pH values above 10. It is noteworthy that the pH is not buffered in the Aptian sands because of their low amount in clayey minerals. This effect is now considered for pH-sensitive radionuclide solutes in safety assessment calculations by weighting correspondingly their retention parameters.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Renaut, R.W.; Owen, R.B.

An unusual group of cherts found at saline, alkaline Lake Bogoria in the Kenya Rift differs from the Magadi-type cherts commonly associated with saline, alkaline lakes. The cherts are opaline, rich in diatoms, and formed from a siliceous, probably gelatinous, precursor that precipitated around submerged alkaline hot springs during a Holocene phase of high lake level. Silica precipitation resulted from rapid drop in the temperature of the spring waters and, possibly, pH. Lithification began before subaerial exposure. Ancient analogous cherts are likely to be localized deposits along fault lines.

Alkaline phosphatase as a screening test for osteomalacia.

PubMed

Chinoy, Muhammad Amin; Javed, Muhammad Imran; Khan, Alamzeb; Sadruddin, Nooruddin

2011-01-01

Vitamin D deficiency remains common in children and adults in Pakistan despite adequate sunlight exposure. Diagnosis in adults is usually delayed and is made following pathological fractures that result in significant morbidity. The objective of this study was to see whether Serum Alkaline Phosphatase levels could be used as a screening test for osteomalacia. The Study was conducted at Fatima Hospital, Baqai Medical University, Gadap, Karachi, between July 2002 and June 2005. Serum calcium levels are commonly used to screen patients suspected of osteomalacia, and raised serum alkaline phosphatase (SALP) is considered a diagnostic finding. We used SALP to screen patients who presented with back or non-specific aches and pain of more than six months duration. Three hundred thirty-four (334) patients were screened of which 116 (35%) had raised SALP. Osteomalacia was diagnosed in 92 (79.3%) of these 116 either by plain radiographs, bone biopsy or isotope bone scan. Fifty-four (53.4%) of the 101 cases had a normal level of serum calcium. Osteomalacia is likely to be missed if only serum calcium is used to screen patients. Serum Alkaline Phosphate should be used as the preferred method for screening these patients.

β₂ adrenergic receptor activation suppresses bone morphogenetic protein (BMP)-induced alkaline phosphatase expression in osteoblast-like MC3T3E1 cells.

PubMed

Yamada, Takayuki; Ezura, Yoichi; Hayata, Tadayoshi; Moriya, Shuichi; Shirakawa, Jumpei; Notomi, Takuya; Arayal, Smriti; Kawasaki, Makiri; Izu, Yayoi; Harada, Kiyoshi; Noda, Masaki

2015-06-01

β adrenergic stimulation suppresses bone formation in vivo while its actions in osteoblastic differentiation are still incompletely understood. We therefore examined the effects of β2 adrenergic stimulation on osteoblast-like MC3T3-E1 cells focusing on BMP-induced alkaline phosphatase expression. Morphologically, isoproterenol treatment suppresses BMP-induced increase in the numbers of alkaline phosphatase-positive small foci in the cultures of MC3T3-E1 cells. Biochemically, isoproterenol treatment suppresses BMP-induced enzymatic activity of alkaline phosphatase in a dose-dependent manner. Isoproterenol suppression of alkaline phosphatase activity is observed even when the cells are treated with high concentrations of BMP. With respect to cell density, isoproterenol treatment tends to suppress BMP-induced increase in alkaline phosphatase expression more in osteoblasts cultured at higher cell density. In terms of treatment protocol, continuous isoproterenol treatment is compared to cyclic treatment. Continuous isoproterenol treatment is more suppressive against BMP-induced increase in alkaline phosphatase expression than cyclic regimen. At molecular level, isoproterenol treatment suppresses BMP-induced enhancement of alkaline phosphatase mRNA expression. Regarding the mode of isoproterenol action, isoproterenol suppresses BMP-induced BRE-luciferase activity. These data indicate that isoproterenol regulates BMP-induced alkaline phosphatase expression in osteoblast-like MC3T3E1 cells. © 2014 Wiley Periodicals, Inc.

Caractérisation pétrologique et géochimique du magmatisme ubendien du secteur de Pepa-Lubumba, sur le plateau des Marungu (Nord-Est du Shaba, Zaire). Signification géodynamique dans l'évolution de la chaîne ubendienne

NASA Astrophysics Data System (ADS)

Kabengele, M.; Lubala, R. T.; Cabanis, B.

Volcanic and plutonic rocks of Pepa-Lubumba area in the Marungu plateau (Zaire) are mainly represented by intermediate and acid members which contain low abundances in TiO 2 (0.3 - 1.3 wt%). All these rocks exhibit a high-K calc-alkaline affinity and belong to a calc-alkaline continental-margin series. The large proportion of frequently zoned (normal and reverse zoning) plagioclase, the presence of hydrous phases (tschermakitic and Mg-hornblende, Mg-biotite), the early crystallization of FeTi oxides indicate crystallization under high water pressure conditions, consistent with a calc-alkaline affinity. High abundances in K, Rb, Sr and Ba; lack of correlation between Rb and Ba, low values of Rb/Zr (0.5 - 0.9) in granitoids, high contents of LREE and HFSE (Th/Ta : 6 - 14), are characteristic of "Andinotype" magmas. A whole rock RbSr isochron gives an emplacement age for granitoids of 1861 ± 28 Ma (MSWD : 0.82), Sr initial ratio of 0.7026 and epsilon Sr i of + 4.7. PbPb isotopes systematics for the same rocks give the following ratio ranges : 206Pb/ 204Pb : 17.26 - 20.10; 207Pb/ 204Pb 15.52 - 15.85, 208Pb/ 204Pb : 37.2 - 41.80. The low Sr initial ratio indicates an upper mantle source; while the PBPb isotope ratios suggest that the mantellic liquids have been contaminated by crustal material en route to the upper levels. In the regional geologic context, this magmatism forms a part of an important plutovolcanic Ubendian (Early Proterozoic) complex which crops out in Western Tanzania, North-Eastern Zambia and Marungu plateau (Zaire) and contains two magmatic cycles which define a spatial and temporal zonation suggesting a geodynamic evolution model for the Ubendian belt comprising subduction-obduction-collision processes. This latter episode has been relayed by a relaxation phase marked by emplacement of a third tholeiitic basic plutonic cycle.

Hydrolytic degradation of alkaline lignin in hot-compressed water and ethanol.

PubMed

Yuan, Zhongshun; Cheng, Shuna; Leitch, Mathew; Xu, Chunbao Charles

2010-12-01

Alkaline lignin of a very high molecular weight was successfully degraded into oligomers in a hot-compressed water-ethanol medium with NaOH as the catalyst and phenol as the capping agent at 220-300 degrees C. Under the optimal reaction conditions, i.e., 260 degrees C, 1 h, with the lignin/phenol ratio of 1:1 (w/w), almost complete degradation was achieved, producing <1% solid residue and negligible gas products. The obtained degraded lignin had a number-average molecular weight M(n) and weight-average molecular weight M(w) of 450 and 1000 g/mol respectively, significantly lower than the M(n) and M(w) of 10,000 and 60,000 g/mol of the original lignin. A higher temperature and a longer reaction time favoured phenol combination, but increased the formation of solid residue due to the condensation reactions of the degradation intermediates/products. The degraded lignin products were soluble in organic solvents (such as THF), and were characterized by HPLC/GPC, IR and NMR. A possible mechanism for lignin hydrolytic degradation was also proposed in this study. 2010 Elsevier Ltd. All rights reserved.

Volatile fatty acids production from anaerobic treatment of cassava waste water: effect of temperature and alkalinity.

PubMed

Hasan, Salah Din Mahmud; Giongo, Citieli; Fiorese, Mônica Lady; Gomes, Simone Damasceno; Ferrari, Tatiane Caroline; Savoldi, Tarcio Enrico

2015-01-01

The production of volatile fatty acids (VFAs), intermediates in the anaerobic degradation process of organic matter from waste water, was evaluated in this work. A batch reactor was used to investigate the effect of temperature, and alkalinity in the production of VFAs, from the fermentation of industrial cassava waste water. Peak production of total volatile fatty acids (TVFAs) was observed in the first two days of acidogenesis. A central composite design was performed, and the highest yield (3400 mg L(-1) of TVFA) was obtained with 30°C and 3 g L(-1) of sodium bicarbonate. The peak of VFA was in 45 h (pH 5.9) with a predominance of acetic (63%) and butyric acid (22%), followed by propionic acid (12%). Decreases in amounts of cyanide (12.9%) and chemical oxygen demand (21.6%) were observed, in addition to the production of biogas (0.53 cm(3) h(-1)). The process was validated experimentally and 3400 g L(-1) of TVFA were obtained with a low relative standard deviation.

Corrosion control in water supply systems: effect of pH, alkalinity, and orthophosphate on lead and copper leaching from brass plumbing.

PubMed

Tam, Y S; Elefsiniotis, P

2009-10-01

This study explored the potential of lead and copper leaching from brass plumbing in the Auckland region of New Zealand. A five-month field investigation, at six representative locations, indicated that Auckland's water can be characterized as soft and potentially corrosive, having low alkalinity and hardness levels and a moderately alkaline pH. More than 90% of the unflushed samples contained lead above the maximum acceptable value (MAV) of 10 microg/L (New Zealand Standards). In contrast, the copper level of unflushed samples remained consistently below the corresponding MAV of 2 mg/L. Flushing however reduced sharply metal concentrations, with lead values well below the MAV limit. Generally, metal leaching patterns showed a limited degree of correlation with the variations in temperature, dissolved oxygen and free chlorine residual at all sampling locations. Furthermore, a series of bench-scale experiments was conducted to evaluate the effectiveness of pH and alkalinity adjustment, as well as orthophosphate addition as corrosion control tools regarding lead and copper dissolution. Results demonstrated that lead and copper leaching was predominant during the first 24 hr of stagnation, but reached an equilibrium state afterwards. Since the soluble fraction of both metals was small (12% for lead, 29% for copper), it is apparent that the non-soluble compounds play a predominant role in the dissolution process. The degree of leaching however was largely affected by the variations in pH and alkalinity. At pH around neutrality, an increase in alkalinity promoted metal dissolution, while at pH 9.0 the effect of alkalinity on leaching was marginal. Lastly, addition of orthophosphate as a corrosion inhibitor was more effective at pH 7.5 or higher, resulting in approximately 70% reduction in both lead and copper concentrations.

Defluoridation of drinking water by combined electrocoagulation: effects of the molar ratio of alkalinity and fluoride to Al(III).

PubMed

Zhao, Hua-Zhang; Yang, Wei; Zhu, Jun; Ni, Jin-Ren

2009-03-01

The defluoridation efficiency (epsilon(F)) of electrocoagulation (EC) is closely related to the pH level of the F(-)-containing solution. The pH level usually needs to be adjusted by adding acid in order to obtain the highest epsilon(F) for the F(-)-containing groundwater. The use of combined EC (CEC), which is the combination of chemical coagulation with EC, was proposed to remove fluoride from drinking water for the first time in this study. The optimal scheme for the design and operation of CEC were obtained through experiments on the treatment of F(-)-containing groundwater. It was found, with OH(-) being the only alkalinity of the raw water, that the highest efficiency would be obtained when the molar ratio of alkalinity and fluoride to Al(III) (gamma(Alkalinity+F)) was controlled at 3.0. However, when the raw water contained HCO(3)(-) alkalinity, a correction coefficient was needed to correct the concentration of HCO(3)(-) to obtain the optimal defluoridation condition of gamma(Alkalinity+F)=3.0 for CEC. The correction coefficient of HCO(3)(-) concentration was concluded as 0.60 from the experiment. For the practical F(-)-containing groundwater treatment, CEC can achieve similar epsilon(F) as an acid-adding EC process. The consumption of aluminum electrode was decreased in CEC. The energy consumption also declined greatly in CEC, which is less than one third of that in the acid-adding EC process.

Alkaline β-fructofuranosidases of tuberous roots: Possible physiological function.

PubMed

Ricardo, C P

1974-12-01

Alkaline invertase of roots of carrot (Daucus carota L.) did not hydrolyze raffinose while the acid invertase from the same tissue showed with this sugar ca. 60% of the activity found with sucrose. The activity of the two invertases was inhibited by fructose to a different extent, the K i value being ca. 4×10(-2) M and 3×10(-1)M, respectively, for the alkaline and the acid invertases from the roots of both carrot and turnip (Brassica rapa L.). It is proposed that fructose inhibition of acid invertase is of no physiological significance but that, in contrast, hexoses might regulate the activity of alkaline invertase.Comparing several species and cultivars, it was found that the content of reducing sugars and the activity of alkaline invertase of mature tuberous roots showed a positive correlation. This indicates that alkaline invertase may participate in the regulation of the hexose level of the cell, as was previously suggested for sugar-cane. A scheme is presented which proposes a way of participation of alkaline invertase in such a regulation, assuming that this enzyme is located in the cytoplasm and acid invertase is membrane-bound and mainly located at the cell surface.

Low-heat, mild alkaline pretreatment of switchgrass for anaerobic digestion.

PubMed

Jin, Guang; Bierma, Tom; Walker, Paul M

2014-01-01

This study examines the effectiveness of alkaline pretreatment under mild heat conditions (100°C or 212°F) on the anaerobic co-digestion of switchgrass. The effects of alkaline concentration, types of alkaline, heating time and rinsing were evaluated. In addition to batch studies, continuous-feed studies were performed in triplicate to identify potential digester operational problems caused by switchgrass co-digestion while accounting for uncertainty due to digester variability. Few studies have examined anaerobic digestion of switchgrass or the effects of mild heating to enhance alkaline pretreatment prior to biomass digestion. Results indicate that pretreatment can significantly enhance digestion of coarse-ground (≤ 0.78 cm particle size) switchgrass. Energy conversion efficiency as high as 63% was observed, and was comparable or superior to fine-grinding as a pretreatment method. The optimal NaOH concentration was found to be 5.5% (wt/wt alkaline/biomass) with a 91.7% moisture level. No evidence of operational problems such as solids build-up, poor mixing, or floating materials were observed. These results suggest the use of waste heat from a generator could reduce the concentration of alkaline required to adequately pretreat lignocellulosic feedstock prior to anaerobic digestion.

Calcium-pH crosstalks in rat mast cells: cytosolic alkalinization, but not intracellular calcium release, is a sufficient signal for degranulation

PubMed Central

Alfonso, A; Cabado, A G; Vieytes, M R; Botana, L M

2000-01-01

The aim of this work was to study the relationship between intracellular alkalinization, calcium fluxes and histamine release in rat mast cells. Intracellular alkalinization was induced by nigericin, a monovalent cation ionophore, and by NH4Cl (ammonium chloride). Calcium cytosolic and intracellular pH were measured by fluorescence digital imaging using Fura-2-AM and BCECF-AM.In rat mast cells, nigericin and NH4Cl induce a dose-dependent intracellular alkalinization, a dose-dependent increase in intracellular calcium levels by releasing calcium from intracellular pools, and an activation of capacitative calcium influx.The increase in both intracellular calcium and pH activates exocytosis (histamine release) in the absence of external calcium. Under the same conditions, thapsigargin does not activate exocytosis, the main difference being that thapsigargin does not alkalinize the cytosol.After alkalinization, histamine release is intracellular-calcium dependent. With 2.5 mM EGTA and thapsigargin the cell response decreases by 62%.The cytosolic alkalinization, in addition to the calcium increase it is enough signal to elicit the exocytotic process in rat mast cells. PMID:10952669

Efficient acquisition of iron confers greater tolerance to saline-alkaline stress in rice (Oryza sativa L.).

PubMed

Li, Qian; Yang, An; Zhang, Wen-Hao

2016-12-01

To elucidate the mechanisms underlying tolerance to saline-alkaline stress in two rice genotypes, Dongdao-4 and Jigeng-88, we exposed them to medium supplemented with 10 mM Na 2 CO 3 and 40 mM NaCl (pH 8.5). Dongdao-4 plants displayed higher biomass, chlorophyll content, and photosynthetic rates, and a larger root system than Jigeng-88 under saline-alkaline conditions. Dongdao-4 had a higher shoot Na + /K + ratio than Jigeng-88 under both control and saline-alkaline conditions. Dongdao-4 exhibited stronger rhizospheric acidification than Jigeng-88 under saline-alkaline conditions, resulting from greater up-regulation of H + -ATPases at the transcriptional level. Moreover, Fe concentrations in shoots and roots of Dongdao-4 were higher than those in Jigeng-88, and a higher rate of phytosiderophore exudation was detected in Dongdao-4 versus Jigeng-88 under saline-alkaline conditions. The Fe-deficiency-responsive genes OsIRO2, OsIRT1, OsNAS1, OsNAS2, OsYSL2, and OsYSL15 were more strongly up-regulated in Dongdao-4 than Jigeng-88 plants in saline-alkaline medium, implying greater tolerance of Dongdao-4 plants to Fe deficiency. To test this hypothesis, we compared the effects of Fe deficiency on the two genotypes, and found that Dongdao-4 was more tolerant to Fe deficiency. Exposure to Fe-deficient medium led to greater rhizospheric acidification and phytosiderophore exudation in Dongdao-4 than Jigeng-88 plants. Expression levels of OsIRO2, OsIRT1, OsNAS1, OsNAS2, OsYSL2, and OsYSL15 were higher in Dongdao-4 than Jigeng-88 plants under Fe-deficient conditions. These results demonstrate that a highly efficient Fe acquisition system together with a large root system may underpin the greater tolerance of Dongdao-4 plants to saline-alkaline stress. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Efficient acquisition of iron confers greater tolerance to saline-alkaline stress in rice (Oryza sativa L.)

PubMed Central

Li, Qian; Yang, An; Zhang, Wen-Hao

2016-01-01

To elucidate the mechanisms underlying tolerance to saline-alkaline stress in two rice genotypes, Dongdao-4 and Jigeng-88, we exposed them to medium supplemented with 10 mM Na2CO3 and 40 mM NaCl (pH 8.5). Dongdao-4 plants displayed higher biomass, chlorophyll content, and photosynthetic rates, and a larger root system than Jigeng-88 under saline-alkaline conditions. Dongdao-4 had a higher shoot Na+/K+ ratio than Jigeng-88 under both control and saline-alkaline conditions. Dongdao-4 exhibited stronger rhizospheric acidification than Jigeng-88 under saline-alkaline conditions, resulting from greater up-regulation of H+-ATPases at the transcriptional level. Moreover, Fe concentrations in shoots and roots of Dongdao-4 were higher than those in Jigeng-88, and a higher rate of phytosiderophore exudation was detected in Dongdao-4 versus Jigeng-88 under saline-alkaline conditions. The Fe-deficiency-responsive genes OsIRO2, OsIRT1, OsNAS1, OsNAS2, OsYSL2, and OsYSL15 were more strongly up-regulated in Dongdao-4 than Jigeng-88 plants in saline-alkaline medium, implying greater tolerance of Dongdao-4 plants to Fe deficiency. To test this hypothesis, we compared the effects of Fe deficiency on the two genotypes, and found that Dongdao-4 was more tolerant to Fe deficiency. Exposure to Fe-deficient medium led to greater rhizospheric acidification and phytosiderophore exudation in Dongdao-4 than Jigeng-88 plants. Expression levels of OsIRO2, OsIRT1, OsNAS1, OsNAS2, OsYSL2, and OsYSL15 were higher in Dongdao-4 than Jigeng-88 plants under Fe-deficient conditions. These results demonstrate that a highly efficient Fe acquisition system together with a large root system may underpin the greater tolerance of Dongdao-4 plants to saline-alkaline stress. PMID:27811002

Zirconia coating stabilized super-iron alkaline cathodes

NASA Astrophysics Data System (ADS)

Yu, Xingwen; Licht, Stuart

A low-level zirconia coating significantly stabilizes high energy alkaline super-iron cathodes, and improves the energy storage capacity of super-iron batteries. Zirconia coating is derived from ZrCl 4 in an organic medium through the conversion of ZrCl 4 to ZrO 2. In alkaline battery system, ZrO 2 provides an intact shield for the cathode materials and the hydroxide shuttle through the coating sustains alkaline cathode redox chemistry. Most super-iron cathodes are solid-state stable, such as K 2FeO 4 and Cs 2FeO 4, but tend to be passivated in alkaline electrolyte due to the formation of Fe(III) over layer. Zirconia coating effectively enhances the stability of these super-iron cathodes. However, for solid-state unstable super-iron cathode (e.g. BaFeO 4), only a little stabilization effect of zirconia coating is observed.

Control of New Copper Corrosion in High-Alkalinity Drinking Water using Orthophosphate - article

EPA Science Inventory

Research and field experience have shown that high-alkalinity waters can be associated with elevated copper levels in drinking water. The objective of this study was to document the application of orthophosphate to the distribution system of a building with a copper problem asso...

Highly CO2-Tolerant Cathode for Intermediate-Temperature Solid Oxide Fuel Cells: Samarium-Doped Ceria-Protected SrCo0.85Ta0.15O3-δ Hybrid.

PubMed

Li, Mengran; Zhou, Wei; Zhu, Zhonghua

2017-01-25

Susceptibility to CO 2 is one of the major challenges for the long-term stability of the alkaline-earth-containing cathodes for intermediate-temperature solid oxide fuel cells. To alleviate the adverse effects from CO 2 , we incorporated samarium-stabilized ceria (SDC) into a SrCo 0.85 Ta 0.15 O 3-δ (SCT15) cathode by either mechanical mixing or a wet impregnation method and evaluated their cathode performance stability in the presence of a gas mixture of 10% CO 2 , 21% O 2 , and 69% N 2 . We observed that the CO 2 tolerance of the hybrid cathode outperforms the pure SCT15 cathode by over 5 times at 550 °C. This significant enhancement is likely attributable to the low CO 2 adsorption and reactivity of the SDC protective layer, which are demonstrated through thermogravimetric analysis, energy-dispersive spectroscopy, and electrical conductivity study.

[Synthesis and spectral characteristic of Ga-Fe3O4 at room temperature].

PubMed

Wang, Jing; Deng, Tong; Yang, Cai-Qin; Lin, Yu-Long; Wang, Wei; Wu, Hai-Yan

2008-03-01

Gallium bearing ferrites with different gallium content were synthesized by oxidation of ferrous and gallium ions under alkaline condition and room temperature. The samples were subjected to IR, XRD, Mossbauer spectral analysis and magnetization characterization. The results indicated that the green-rust intermediate phase would be produced during the procedure of Ga-Fe3O4 formation, and the green-rust intermediate phase was converted to ferrites with spinel structure during the drying under hot-N2 atmosphere. With the introduction of gallium into the spinel structure, the interplanar crystal spacing of the spinel structure decreased, as indicated from XRD spectra, and the lattice vibration of M(T)-O-M(o) moved to the high-frequency resulting from IR spectra. A small amount gallium introduction entered the tetrahedral sites preferentially rather than the octahedral sites, and increasing gallium introduction would enhance the occupation of octahedral sites. Furthermore, a small content of gallium in the initial solution could prevent the formation of non-magnetic Fe2O3.

Particle Size, Composition, and Ocean Temperature Govern the Global Distribution of Particle Transfer Efficiency to the Mesopelagic

NASA Astrophysics Data System (ADS)

Cram, J. A.; Weber, T. S.; Leung, S.; Deutsch, C. A.

2016-02-01

New analyses of geochemical tracer data detect significant differences between ocean basins in the depth scale of particle remineralization, with deepest in high latitudes, shallowest in the subtropical gyres, and intermediate in the tropics. We evaluate the possible causes of this pattern using a mechanistic model of particle dynamics that includes microbial colonization, detachment, and degradation of sinking particles. The model represents the size structure of particles, the effects of mineral ballast (diagnosed from alkalinity and silicate distributions) and seawater temperature (which influences particle velocity and microbial metabolic rates). We find that diagnosed spatial patterns in particle flux profiles can be best reproduced through a combination of surface particle size distribution and temperature, which both favor low transfer efficiency in subtropical gyres, and high transfer efficiency in higher latitudes and intermediate tropical values. Particle mineral content is shown to significantly modulate these patterns, albeit with a high remaining uncertainty. Implications of these mechanisms for changes in biological carbon storage in a warmer ocean are examined.

Intermediate-consumer identity and resources alter a food web with omnivory.

PubMed

Kneitel, Jamie M

2007-07-01

1. Omnivory is an important interaction that has been the centre of numerous theoretical and empirical studies in recent years. Most of these studies examine the conditions necessary for coexistence between an omnivore and an intermediate consumer. Trait variation in ecological interactions (competition and predator tolerance) among intermediate consumers has not been considered in previous empirical studies despite the evidence that variation in species-specific traits can have important community-level effects. 2. I conducted a multifactorial microcosm experiment using species from the Sarracenia purpurea phytotelmata community, organisms that inhabit the water collected within its modified leaves. The basal trophic level consisted of bacterial decomposers, the second trophic level (intermediate consumers) consisted of protozoa and rotifers, and the third trophic level (omnivore) were larvae of the pitcher plant mosquito Wyeomyia smithii. Trophic level number (1, 2 and 3), resources (low and high), omnivore density (low and high) and intermediate consumer (monoculture of five protozoa and rotifers) identity were manipulated. Abundance of the basal trophic level, intermediate consumers, and growth of the omnivore were measured, as well as time to extinction (intermediate consumers) and time to pupation (mosquito larvae). 3. The presence of different intermediate consumers affected both bacteria abundance and omnivore growth. At high resource levels, Poteriochromonas, Colpidium and Habrotrocha rosa reduced bacteria densities greater than omnivore reduction of bacteria. Mosquito larvae did not pupate at low resource levels except when Poteriochromonas and Colopoda were present as intermediate consumers. Communities with H. rosa were the only ones consistent with the prediction that omnivores should exclude intermediate consumers at high resources. 4. These results had mixed support for predictions from omnivory food web theory. Intermediate consumers responded and affected this community differently under different community structures and resource levels. Consequently, variation in species-specific traits can have important population- and community-level effects and needs to be considered in food webs with omnivory.

New Stability Indicating RP-HPLC Method for the Estimation of Cefpirome Sulphate in Bulk and Pharmaceutical Dosage Forms.

PubMed

Rao, Kareti Srinivasa; Kumar, Keshar Nargesh; Joydeep, Datta

2011-01-01

A simple stability indicating reversed-phase HPLC method was developed and subsequently validated for estimation of Cefpirome sulphate (CPS) present in pharmaceutical dosage forms. The proposed RP-HPLC method utilizes a LiChroCART-Lichrosphere100, C18 RP column (250 mm × 4mm × 5 μm) in an isocratic separation mode with mobile phase consisting of methanol and water in the proportion of 50:50 % (v/v), at a flow rate 1ml/min, and the effluent was monitored at 270 nm. The retention time of CPS was 2.733 min and its formulation was exposed to acidic, alkaline, photolytic, thermal and oxidative stress conditions, and the stressed samples were analyzed by the proposed method. The described method was linear over a range of 0.5-200μg/ml. The percentage recovery was 99.46. F-test and t-test at 95% confidence level were used to check the intermediate precision data obtained under different experimental setups; the calculated value was found to be less than the critical value.

Effects of enzyme loading and β-glucosidase supplementation on enzymatic hydrolysis of switchgrass processed by leading pretreatment technologies.

PubMed

Pallapolu, Venkata Ramesh; Lee, Y Y; Garlock, Rebecca J; Balan, Venkatesh; Dale, Bruce E; Kim, Youngmi; Mosier, Nathan S; Ladisch, Michael R; Falls, Matthew; Holtzapple, Mark T; Sierra-Ramirez, Rocio; Shi, Jian; Ebrik, Mirvat A; Redmond, Tim; Yang, Bin; Wyman, Charles E; Donohoe, Bryon S; Vinzant, Todd B; Elander, Richard T; Hames, Bonnie; Thomas, Steve; Warner, Ryan E

2011-12-01

The objective of this work is to investigate the effects of cellulase loading and β-glucosidase supplementation on enzymatic hydrolysis of pretreated Dacotah switchgrass. To assess the difference among various pretreatment methods, the profiles of sugars and intermediates were determined for differently treated substrates. For all pretreatments, 72 h glucan/xylan digestibilities increased sharply with enzyme loading up to 25mg protein/g-glucan, after which the response varied depending on the pretreatment method. For a fixed level of enzyme loading, dilute sulfuric acid (DA), SO(2), and Lime pretreatments exhibited higher digestibility than the soaking in aqueous ammonia (SAA) and ammonia fiber expansion (AFEX). Supplementation of Novozyme-188 to Spezyme-CP improved the 72 h glucan digestibility only for the SAA treated samples. The effect of β-glucosidase supplementation was discernible only at the early phase of hydrolysis where accumulation of cellobiose and oligomers is significant. Addition of β-glucosidase increased the xylan digestibility of alkaline treated samples due to the β-xylosidase activity present in Novozyme-188. Copyright © 2011 Elsevier Ltd. All rights reserved.

Formation of M-Like Intermediates in Proteorhodopsin in Alkali Solutions (pH ≥ ∼8.5) Where the Proton Release Occurs First in Contrast to the Sequence at Lower pH.

PubMed

Tamogami, Jun; Sato, Keitaro; Kurokawa, Sukuna; Yamada, Takumi; Nara, Toshifumi; Demura, Makoto; Miyauchi, Seiji; Kikukawa, Takashi; Muneyuki, Eiro; Kamo, Naoki

2016-02-23

Proteorhodopsin (PR) is an outward light-driven proton pump observed in marine eubacteria. Despite many structural and functional similarities to bacteriorhodopsin (BR) in archaea, which also acts as an outward proton pump, the mechanism of the photoinduced proton release and uptake is different between two H(+)-pumps. In this study, we investigated the pH dependence of the photocycle and proton transfer in PR reconstituted with the phospholipid membrane under alkaline conditions. Under these conditions, as the medium pH increased, a blue-shifted photoproduct (defined as Ma), which is different from M, with a pKa of ca. 9.2 was produced. The sequence of the photoinduced proton uptake and release during the photocycle was inverted with the increase in pH. A pKa value of ca. 9.5 was estimated for this inversion and was in good agreement with the pKa value of the formation of Ma (∼ 9.2). In addition, we measured the photoelectric current generated by PRs attached to a thin polymer film at varying pH. Interestingly, increases in the medium pH evoked bidirectional photocurrents, which may imply a possible reversal of the direction of the proton movement at alkaline pH. On the basis of these findings, a putative photocycle and proton transfer scheme in PR under alkaline pH conditions was proposed.

Understanding Intermediate-Level Speakers' Strengths and Weaknesses: An Examination of OPIc Tests from Korean Learners of English

ERIC Educational Resources Information Center

Cox, Troy L.

2017-01-01

This study profiled Intermediate-level learners in terms of their linguistic characteristics and performance on different proficiency tasks. A stratified random sample of 300 Korean learners of English with holistic ratings of Intermediate Low (IL), Intermediate Mid (IM), and Intermediate High (IH) on Oral Proficiency Interviews-computerized…

Distinctly different parental magmas for plutons and lavas in the central Aleutian arc

NASA Astrophysics Data System (ADS)

Cai, Y.; Rioux, M. E.; Kelemen, P. B.; Goldstein, S. L.; Bolge, L.; Kylander-Clark, A. R.

2014-12-01

While it is generally agreed that continental crust is generated by arc magmatism, average arc lavas are basaltic while the bulk continental crust is andesitic, and this has led to many models for secondary reprocessing of the arc crust in order to form continental crust. We report new data on calc-alkaline plutons in the central Aleutians showing that they have distinctly different sources compared to Holocene tholeiitic lavas. Therefore the lavas are not representative of the net magmatic transfer from the mantle into the arc crust. Eocene to Miocene (9-39 Ma) intermediate to felsic plutonic rocks from the central Aleutian arc show higher SiO2 at a given Mg#, higher ɛNd- and ɛHf-values, and lower Pb isotope ratios than Holocene volcanic rocks from the same region. Instead, the plutonic rocks resemble volcanics from the western Aleutians isotopically, and have chemical compositions similar to bulk continental crust. These data could reflect temporal variation of Aleutian magma source compositions, from Eocene-Miocene "isotopically depleted" and predominantly calc-alkaline to Holocene "isotopically enriched" and predominantly tholeiitic. Alternatively, they may reflect different transport and emplacement processes for the magmas that form plutons and lavas: calc-alkaline magmas with higher Si content and high viscosity may preferentially form plutons, perhaps after extensive mid-crustal degassing of initially high water contents. The latter case implies that the upper and middle arc crust is more like the calc-alkaline bulk composition of the continental crust than the lavas alone. Crustal reprocessing mechanisms that preserve upper and middle arc crust, while removing lower arc crust, can account for the genesis and evolution of continental crust. Since gabbroic lower arc crust extends from ca 20-40 km depth, and is density stable over most of this depth range, "delamination" of dense lithologies [1] may not be sufficient to accomplish this. Alternatively, subduction erosion of arc crust followed by "relamination" [2] of buoyant calc-alkaline rocks may be more effective. [1] e.g. Ringwood & Green, Tectonophysics 1966; Herzberg et al. Contributions to mineralogy and petrology 1983; [2] e.g. Hacker et al. Earth and Planetary Science Letters 2011.

Localization of inclusion bodies in Escherichia coli overproducing beta-lactamase or alkaline phosphatase.

PubMed Central

Georgiou, G; Telford, J N; Shuler, M L; Wilson, D B

1986-01-01

High-level synthesis of the periplasmic protein beta-lactamase in Escherichia coli caused the formation of insoluble protein precipitates called inclusion bodies. beta-Lactamase inclusion bodies differed from those reported previously in that they appeared to be localized in the periplasmic space, not in the cytoplasm. The inclusion bodies contained mature beta-lactamase and were solubilized more easily than has been reported for cytoplasmic inclusion bodies. In contrast, overproduction of the periplasmic protein alkaline phosphatase caused the formation of cytoplasmic inclusion bodies containing alkaline phosphatase precursor. Images PMID:3539017

Characterization of Human Bone Alkaline Phosphatase in Pichia Pastoris

NASA Technical Reports Server (NTRS)

Malone, Christine C.; Ciszak, Eva; Karr, Laurel J.

1999-01-01

A soluble form of human bone alkaline phosphatase has been expressed in a recombinant strain of the methylotrophic yeast Pichia pastoris. We constructed a plasmid containing cDNA encoding for human bone alkaline phosphatase, with the hydrophobic carboxyl terminal portion deleted. Alkaline phosphatase was secreted into the medium to a level of 32mg/L when cultured in shake flasks, and enzyme activity was 12U/mg, as measured by a spectrophotometric assay. By conversion to a fermentation system, a yield of 880mg/L has been achieved with an enzyme activity of 968U/mg. By gel electrophoresis analysis, it appears that greater than 50% of the total protein in the fermentation media is alkaline phosphatase. Although purification procedures are not yet completely optimized, they are expected to include filtration, ion exchange and affinity chromatography. Our presentation will focus on the purification and crystallization results up to the time of the conference. Structural data should provide additional information on the role of alkaline phosphatase in normal bone mineralization and in certain bone mineralization anomalies.

A-type granites and related rocks: Evolution of a concept, problems and prospects

NASA Astrophysics Data System (ADS)

Bonin, Bernard

2007-08-01

Although A-type granites have long been recognized as a distinct group of granites, the term A-type was coined first less than thirty years ago. A-type suites occur in geodynamic contexts ranging from within-plate settings to plate boundaries, locations and times of emplacement are not random. Rare in the lower crust, as some charnockite suites, they are fairly common at shallower depths, especially at the subvolcanic level where they form ring complexes rooting caldera volcanoes. Characteristic features include hypersolvus to transsolvus to subsolvus alkali feldspar textures, iron-rich mafic mineralogy, bulk-rock compositions yielding ferroan, alkali-calcic to alkaline affinities, high LILE+HFSE abundances, and pronounced anomalies due to high degrees of mineral fractionation. Isotopic features evidence sources containing a large mantle input. Experimental data show that A-type magmas contain dissolved OH F-bearing fluids, crystallised under reduced and oxidized conditions, and yield high-temperature liquidus, favouring early crystallisation of anhydrous iron minerals, such as fayalite. Though many petrogenetic models imply solely crustal derivation, no convincing A-type liquids were produced experimentally from crustal materials, nor have any leucosomes of A-type composition been detected within migmatitic terranes. As it occurs in association with mafic igneous rocks in continents as well as on the ocean floor, A-type granite is likely to come from mantle-derived transitional to alkaline mafic to intermediate magmas. Rare felsic materials found in the meteoritic and lunar record yield dominantly A-type features. Contrary to the more common types of granite, A-type granite is, therefore, not typical of Earth and was produced in planetary environments differing from those prevailing on Earth.

Intestinal Alkaline Phosphatase Regulates Tight Junction Protein Levels

PubMed Central

Liu, Wei; Hu, Dong; Huo, Haizhong; Zhang, Weifeng; Adiliaghdam, Fatemeh; Morrison, Sarah; Ramirez, Juan M; Gul, Sarah S; Hamarneh, Sulaiman R; Hodin, Richard A

2017-01-01

BACKGROUND Intestinal alkaline phosphatase (IAP) plays a pivotal role in maintaining gut health and well-being. Oral supplementation with IAP in mice improves gut barrier function and prevents luminal proinflammatory factors from gaining access to the circulation. In this study, we sought to explore the relationship between IAP and tight junction protein (TJP) expression and function. STUDY DESIGN The effect of IAP deletion on TJP levels was studied in mouse embryonic fibroblasts (MEFs) generated from IAP-knockout and wild type mice. Regulation of TJPs by IAP was assayed in the human colon cancer Caco-2 and T84 cells by overexpressing the human IAP gene. Tight junction protein levels and localization were measured by using RT q-PCR and antibodies targeting the specific TJPs. Finally, the effect of IAP on inflammation-induced intestinal permeability was measured by in vitro trans-well epithelial electrical resistance (TEER). RESULTS Intestinal alkaline phosphatase gene deletion in MEFs resulted in significantly lower levels of ZO-1, ZO-2, and Occludin compared with levels in wild-type control cells; IAP over-expression in Caco-2 and T84 cells resulted in approximate 2-fold increases in the mRNA levels of ZO-1 and ZO-2. The IAP treatment ameliorated lipopolysaccharide-induced increased permeability in the Caco-2 trans-well system. Furthermore, IAP treatment preserved the localization of the ZO-1 and Occludin proteins during inflammation and was also associated with improved epithelial barrier function. CONCLUSIONS Intestinal alkaline phosphatase is a major regulator of gut mucosal permeability and appears to work at least partly through improving TJP levels and localization. These data provide a strong foundation to develop IAP as a novel therapy to maintain gut barrier function. PMID:27106638

Intestinal Alkaline Phosphatase Regulates Tight Junction Protein Levels.

PubMed

Liu, Wei; Hu, Dong; Huo, Haizhong; Zhang, Weifeng; Adiliaghdam, Fatemeh; Morrison, Sarah; Ramirez, Juan M; Gul, Sarah S; Hamarneh, Sulaiman R; Hodin, Richard A

2016-06-01

Intestinal alkaline phosphatase (IAP) plays a pivotal role in maintaining gut health and well-being. Oral supplementation with IAP in mice improves gut barrier function and prevents luminal proinflammatory factors from gaining access to the circulation. In this study, we sought to explore the relationship between IAP and tight junction protein (TJP) expression and function. The effect of IAP deletion on TJP levels was studied in mouse embryonic fibroblasts (MEFs) generated from IAP-knockout and wild type mice. Regulation of TJPs by IAP was assayed in the human colon cancer Caco-2 and T84 cells by overexpressing the human IAP gene. Tight junction protein levels and localization were measured by using RT q-PCR and antibodies targeting the specific TJPs. Finally, the effect of IAP on inflammation-induced intestinal permeability was measured by in vitro trans-well epithelial electrical resistance (TEER). Intestinal alkaline phosphatase gene deletion in MEFs resulted in significantly lower levels of ZO-1, ZO-2, and Occludin compared with levels in wild-type control cells; IAP overexpression in Caco-2 and T84 cells resulted in approximate 2-fold increases in the mRNA levels of ZO-1 and ZO-2. The IAP treatment ameliorated lipopolysaccharide-induced increased permeability in the Caco-2 trans-well system. Furthermore, IAP treatment preserved the localization of the ZO-1 and Occludin proteins during inflammation and was also associated with improved epithelial barrier function. Intestinal alkaline phosphatase is a major regulator of gut mucosal permeability and appears to work at least partly through improving TJP levels and localization. These data provide a strong foundation to develop IAP as a novel therapy to maintain gut barrier function. Copyright © 2016. Published by Elsevier Inc.

Ectopic Expression of a Glycine soja myo-Inositol Oxygenase Gene (GsMIOX1a) in Arabidopsis Enhances Tolerance to Alkaline Stress

PubMed Central

Chen, Chen; Sun, Xiaoli; Duanmu, Huizi; Yu, Yang; Liu, Ailin; Xiao, Jialei; Zhu, Yanming

2015-01-01

Myo-inositol participates in various aspects of plant physiology, and myo-inositol oxygenase is the key enzyme of the myo-inositol oxygenation pathway. Previous studies indicated that myo-inositol oxygenase may play a role in plant responses to abiotic stresses. In this study, we focused on the functional characterization of GsMIOX1a, a remarkable alkaline stress-responsive gene of Glycine soja 07256, based on RNA-seq data. Using quantitative real-time PCR, we demonstrated that GsMIOX1a is rapidly induced by alkaline stress and expressed predominantly in flowers. We also elucidated the positive function of GsMIOX1a in the alkaline response in the wild type, atmiox1 mutant as well as GsMIOX1a-overexpressing Arabidopsis. We determined that atmiox1 mutant decreased Arabidopsis tolerance to alkaline stress, whereas GsMIOX1a overexpression increased tolerance. Moreover, the expression levels of some alkaline stress-responsive and inducible marker genes, including H+-Ppase, NADP-ME, KIN1 and RD29B, were also up-regulated in GsMIOX1a overexpression lines compared with the wild type and atmiox1 mutant. Together, these results suggest that the GsMIOX1a gene positively regulates plant tolerance to alkaline stress. This is the first report to demonstrate that ectopic expression of myo-inositol oxygenase improves alkaline tolerance in plants. PMID:26091094

Silicon Priming Created an Enhanced Tolerance in Alfalfa (Medicago sativa L.) Seedlings in Response to High Alkaline Stress

PubMed Central

Liu, Duo; Liu, Miao; Liu, Xiao-Long; Cheng, Xian-Guo; Liang, Zheng-Wei

2018-01-01

Alkaline stress as a result of higher pH usually triggers more severe physiological damage to plants than that of saline stress with a neutral pH. In the present study, we demonstrated that silicon (Si) priming of alfalfa (Medicago sativa L.) seedlings increased their tolerance to high alkaline stress situations. Gongnong No. 1 seedlings were subjected to alkaline stress simulated by 25 mM Na2CO3 (pH 11.2). Alkaline stress greatly decreased the biomass and caused severe lodging or wilting of alfalfa seedlings. In contrast, the application of Si to alfalfa seedlings 36 h prior to the alkaline treatment significantly alleviated the damage symptoms and greatly increased the biomass and chlorophyll content. Because of being concomitant with increasing photosynthesis and water use efficiency, decreasing membrane injury and malondialdehyde content, and increasing peroxidase and catalase ascorbate activities in alfalfa leaves, thereby alleviating the triggered oxidative damage by alkaline stress to the plant. Furthermore, Si priming significantly decreased the accumulation of protein and proline content in alfalfa, thus reducing photosynthetic feedback repression. Si priming significantly accumulated more Na in the roots, but led to a decrease of Na accumulation and an increase of K accumulation in the leaves under alkaline stress. Meanwhile, Si priming decreased the accumulation of metal ions such as Mg, Fe, Mn, and Zn in the roots of alfalfa seedlings under alkaline stress. Collectively, these results suggested that Si is involved in the metabolic or physiological changes and has a potent priming effect on the alkaline tolerance of alfalfa seedlings. The present study indicated that Si priming is a new approach to improve the alkaline tolerance in alfalfa and provides increasing information for further exploration of the alkaline stress response at the molecular level in alfalfa. PMID:29896213

Alkaline phosphatase activity of water column fractions and seagrass in a tropical carbonate estuary, Florida Bay

NASA Astrophysics Data System (ADS)

Koch, Marguerite S.; Kletou, Demetris C.; Tursi, Rosanna

2009-08-01

Few phosphorus-depleted coastal ecosystems have been examined for their ability to hydrolyze phosphomonoesters. We examined seasonal (August 2006-April 2007) alkaline phosphatase activity in Florida Bay, a phosphorus-limited shallow estuary, using fluorescent substrate at low concentrations (≤2.0 μM). In situ dissolved inorganic and organic phosphorus levels and phosphomonoester concentrations were also determined. Water column alkaline phosphatase activity was partitioned into two particulate size fractions (>1.2 and 0.2-1.2 μm) and freely dissolved enzymes (<0.2 μm). Water column alkaline phosphatase activity was also compared to leaf and epiphyte activity of the dominant tropical seagrass Thalassia testudinum. Our results indicate: (1) potential alkaline phosphatase activity in Florida Bay is high compared to other marine ecosystems, resulting in rapid phosphomonoester turnover times (˜2 h). (2) Water column alkaline phosphatase activity dominates, and is split equally between particulate and dissolved fractions. (3) Alkaline phosphatase activity was highest during cyanobacterial blooms, but not when normalized to chl a. These results suggest that dissolved, heterotrophic and autotrophic alkaline phosphatase activity is stimulated by phytoplankton blooms. (4) The dissolved alkaline phosphatase activity is relatively constant, while the particulate activity is seasonally and spatially dynamic, typically associated with phytoplankton blooms. (5) Phosphomonoester concentrations throughout the bay are low, even though potential hydrolysis rates are high. We propose that bioavailable dissolved organic P is hydrolyzed by dissolved and microbial alkaline phosphatase enzymes in Florida Bay. High alkaline phosphatase activity in the bay is also promoted by long hydraulic residence times. This background activity is primarily driven by carbon and phosphorus limitation of microorganisms, and regeneration of enzymes associated with cell lysis. Pulses of inorganic phosphorus and labile organic phosphorus and nitrogen may stimulate autotrophs, particularly cyanobacteria, which in turn promote biological activity that increase alkaline phosphatase activity of both autotrophs and heterotrophs in the bay.

[The influence of melatonin and epithalon on blood leukocyte count and leukocyte alkaline phosphatase in rats under different lighting conditions during ontogenesis].

PubMed

Uzenbaeva, L B; Vinogradova, I A; Golubeva, A G; Niuppieva, M G; Iliukha, V A

2008-01-01

The effect of pineal body hormone melatonin and synthetic tetrapeptide epithalon (Ala-Glu-Asp-Gly) under different light conditions on leucocytes differential count in rats were investigated. It has been established that melatonin and epithalon decrease the level of blood leucocytes and relative content of band neutrophils in 12 months rats which was higher in the constant light more than in other photoperiod. The melatonin prevents age-specific decreasing blood lymphocytes level in standard photoperiod (12 h light/12 h darkness). Contrary to melatonin, epithalon significantly reduces the number of lymphocytes and increases the number of neutrophils in some age period. The leucocytes alkaline phosphatase activity was increased during aging. Constant light in compare with other light conditions promotes early increasing of alkaline phosphatase activity (at 12 months), associated with accelerated development of pathological process in organism. The melatonin and epithalon adjacency effect on increasing of alkaline phosphatase activity under the standard as well as natural light condition demonstrate homeostatic character of geroprotectors action furthermore depend on leucocytes functional status.

Hydrogeologic framework and geochemistry of the intermediate aquifer system in parts of Charlotte, De Soto, and Sarasota counties, Florida

USGS Publications Warehouse

Torres, A.E.; Sacks, L.A.; Yobbi, D.K.; Knochenmus, L.A.; Katz, B.G.

2001-01-01

The hydrogeologic framework underlying the 600-square-mile study area in Charlotte, De Soto, and Sarasota Counties, Florida, consists of the surficial aquifer system, the intermediate aquifer system, and the Upper Floridan aquifer. The hydrogeologic framework and the geochemical processes controlling ground-water composition were evaluated for the study area. Particular emphasis was given to the analysis of hydrogeologic and geochemical data for the intermediate aquifer system. Flow regimes are not well understood in the intermediate aquifer system; therefore, hydrogeologic and geochemical information were used to evaluate connections between permeable zones within the intermediate aquifer system and between overlying and underlying aquifer systems. Knowledge of these connections will ultimately help to protect ground-water quality in the intermediate aquifer system. The hydrogeology was interpreted from lithologic and geophysical logs, water levels, hydraulic properties, and water quality from six separate well sites. Water-quality samples were collected from wells located along six ground-water flow paths and finished at different depth intervals. The selection of flow paths was based on current potentiometric-surface maps. Ground-water samples were analyzed for major ions; field parameters (temperature, pH, specific conductance, and alkalinity); stable isotopes (deuterium, oxygen-18, and carbon-13); and radioactive isotopes (tritium and carbon-14). The surficial aquifer system is the uppermost aquifer, is unconfined, relatively thin, and consists of unconsolidated sand, shell, and limestone. The intermediate aquifer system underlies the surficial aquifer system and is composed of clastic sediments interbedded with carbonate rocks. The intermediate aquifer system is divided into three permeable zones, the Tamiami/Peace River zone (PZ1), the Upper Arcadia zone (PZ2), and the Lower Arcadia zone (PZ3). The Tamiami/Peace River zone (PZ1) is the uppermost zone and is the thinnest and generally, the least productive zone in the intermediate aquifer system. The Upper Arcadia zone (PZ2) is the middle zone and productivity is generally higher than the overlying permeable zone. The Lower Arcadia zone (PZ3) is the lowermost permeable zone and is the most productive zone in the intermediate aquifer system. The intermediate aquifer system is underlain by the Upper Floridan aquifer, which consists of a thick, stratified sequence of limestone and dolomite. The Upper Floridan aquifer is the most productive aquifer in the study area; however, its use is generally restricted because of poor water quality. Interbedded clays and fine-grained clastics separate the aquifer systems and permeable zones. The hydraulic properties of the three aquifer systems are spatially variable. Estimated trans-missivity and horizontal hydraulic conductivity varies from 752 to 32,900 feet squared per day and from 33 to 1,490 feet per day, respectively, for the surficial aquifer system; from 47 to 5,420 feet squared per day and from 2 to 102 feet per day, respectively, for the Tamiami/Peace River zone (PZ1); from 258 to 24,633 feet squared per day and from 2 to 14 feet per day, respectively, for the Upper Arcadia zone (PZ2); from 766 to 44,900 feet squared per day and from 10 to 201 feet per day, respectively, for the Lower Arcadia zone (PZ3); and from 2,350 to 7,640 feet squared per day and from 10 to 41 feet per day, respectively, for the Upper Floridan aquifer. Confining units separating the aquifer systems have leakance coefficients estimated to range from 2.3 x 10-5 to 5.6 x 10-3 feet per day per foot. Strata composing the confining unit separating the Upper Floridan aquifer from the intermediate aquifer system are substantially more permeable than confining units separating the permeable zones in the intermediate aquifer system or separating the surficial aquifer and intermediate aquifer systems. In Charlotte, Sarasota, and western De Soto Counties, hydraulic

Carbonic anhydrase 2-like and Na⁺-K⁺-ATPase α gene expression in medaka (Oryzias latipes) under carbonate alkalinity stress.

PubMed

Yao, Zongli; Lai, Qifang; Hao, Zhuoran; Chen, Ling; Lin, Tingting; Zhou, Kai; Wang, Hui

2015-12-01

High carbonate alkalinity is one of the major stress factors for living organisms in saline-alkaline water areas. Acute and chronic effects of carbonate alkalinity on expression of two genes, carbonic anhydrase 2-like (CA2-like) and Na(+)-K(+)-ATPase α subunit (NKA-α) mRNA in medaka (Oryzias latipes) were evaluated to better understand the responses important for coping with a carbonate alkalinity stress. In the acute exposure experiment, the expression of CA2-like and NKA-α mRNA in the gill and kidney of medaka were examined from 0 h to 7 days exposed to 30.4 mM carbonate alkalinity water. Exposure to high carbonate alkalinity resulted in a transitory alkalosis, followed by a transient increase in gill and kidney CA2-like and NKA-α mRNA expression. In the chronic exposure experiment, the expression of these two genes was examined in the gill and kidney at 50 days post-exposure to six different carbonate alkalinity concentrations ranging from 1.5 to 30.4 mM. Gill and kidney CA2-like mRNA levels in 30.4 mM were approximately 10 and 30 times higher than that of the control (1.5 mM), respectively. Less differences were found in NKA-α expression in the 50-days exposure. The results indicate that when transferred to high carbonate alkalinity water, a transitory alkalosis may occur in medaka, followed by compensatory acid-base and ion regulatory responses. Thus, CA2-like and NKA-α are at least two of the important factors that contribute to the regulation of alkalinity stress.

Role of the Group 2 Mrp sodium/proton antiporter in rapid response to high alkaline shock in the alkaline- and salt-tolerant Dietzia sp. DQ12-45-1b.

PubMed

Fang, Hui; Qin, Xiao-Yu; Zhang, Kai-Duan; Nie, Yong; Wu, Xiao-Lei

2018-04-01

The six- and seven-subunit Na + /H + antiporters (Mrp) are widely distributed in bacteria. They are reported to be integral for pH homeostasis in alkaliphilic bacteria when adapting to high pH environments. In this study, operons encoding for the six-subunit Na + /H + antiporters were found in the genomes of all studied Dietzia strains, which have different alkaline-resistant abilities. Disruption of the operon in the strain Dietzia sp. DQ12-45-1b which leads to declined growth in presence of hypersaline and alkaline conditions suggested that the six-subunit Na + /H + antiporter played an important role in hypersaline and alkaline resistance. Although the complexes DqMrp from DQ12-45-1b (strain with high alkaline resistance) and DaMrp from D. alimentaria 72 T (strain with low alkaline resistance) displayed Na + (Li + )/H + antiport activities, they functioned optimally at different pH levels (9.0 for DQ12-45-1b and 8.0 for 72 T ). While both antiporters functioned properly to protect Escherichia coli cells from salt shock, only the DqMrp-containing strain survived the high alkaline shock. Furthermore, real-time PCR results showed that the expression of mrpA and mrpD induced only immediately after DQ12-45-1b cells were subjected to the alkaline shock. These results suggested that the expression of DqMrp might be induced by a pH gradient across the cell membrane, and DqMrp mainly functioned at an early stage to respond to the alkaline shock.

Alkaline phosphatase in osteoblasts is down-regulated by pulsatile fluid flow

NASA Technical Reports Server (NTRS)

Hillsley, M. V.; Frangos, J. A.

1997-01-01

It is our hypothesis that interstitial fluid flow plays a role in the bone remodeling response to mechanical loading. The fluid flow-induced expression of three proteins (collagen, osteopontin, and alkaline phosphatase) involved in bone remodeling was investigated. Rat calvarial osteoblasts subjected to pulsatile fluid flow at an average shear stress of 5 dyne/cm2 showed decreased alkaline phosphatase (AP) mRNA expression after only 1 hour of flow. After 3 hours of flow, AP mRNA levels had decreased to 30% of stationary control levels and remained at this level for an additional 5 hours of flow. Steady flow (4 dyne/cm2 fluid shear stress), in contrast, resulted in a delayed and less dramatic decrease in AP mRNA expression to 63% of control levels after 8 hours of flow. The reduced AP mRNA expression under pulsatile flow conditions was followed by reduced AP enzyme activity after 24 hours. No changes in collagen or osteopontin mRNA expression were detected over 8 hours of pulsatile flow. This is the first time fluid flow has been shown to affect gene expression in osteoblasts.

Overexpression of Human Bone Alkaline Phosphatase in Pichia Pastoris

NASA Technical Reports Server (NTRS)

Karr, Laurel; Malone, Christine, C.; Rose, M. Franklin (Technical Monitor)

2000-01-01

The Pichiapastoris expression system was utilized to produce functionally active human bone alkaline phosphatase in gram quantities. Bone alkaline phosphatase is a key enzyme in bone formation and biomineralization, yet important questions about its structural chemistry and interactions with other cellular enzymes in mineralizing tissues remain unanswered. A soluble form of human bone alkaline phosphatase was constructed by deletion of the 25 amino acid hydrophobic C-terminal region of the encoding cDNA and inserted into the X-33 Pichiapastoris strain. An overexpression system was developed in shake flasks and converted to large-scale fermentation. Alkaline phosphatase was secreted into the medium to a level of 32mgAL when cultured in shake flasks. Enzyme activity was 12U/mg measured by a spectrophotometric assay. Fermentation yielded 880mgAL with enzymatic activity of 968U/mg. Gel electrophoresis analysis indicates that greater than 50% of the total protein in the fermentation is alkaline phosphatase. A purification scheme has been developed using ammonium sulfate precipitation followed by hydrophobic interaction chromatography. We are currently screening crystallization conditions of the purified recombinant protein for subsequent X-ray diffraction analyses. Structural data should provide additional information on the role of alkaline phosphatase in normal bone mineralization and in certain bone mineralization anomalies.

Chitosan biopolymer for fuel cell applications.

PubMed

Ma, Jia; Sahai, Yogeshwar

2013-02-15

Fuel cell is an electrochemical device which converts chemical energy stored in a fuel into electrical energy. Fuel cells have been receiving attention due to its potential applicability as a good alternative power source. Recently, cost-effective and eco-friendly biopolymer chitosan has been extensively studied as a material for membrane electrolytes and electrodes in low to intermediate temperature hydrogen polymer electrolyte fuel cell, direct methanol fuel cell, alkaline fuel cell, and biofuel cell. This paper reviews structure and property of chitosan with respect to its applications in fuel cells. Recent achievements and prospect of its applications have also been included. Copyright © 2012 Elsevier Ltd. All rights reserved.

Impacts of artificial ocean alkalinization on the carbon cycle and climate in Earth system simulations

NASA Astrophysics Data System (ADS)

González, Miriam Ferrer; Ilyina, Tatiana

2016-06-01

Using the state-of-the-art emissions-driven Max Planck Institute Earth system model, we explore the impacts of artificial ocean alkalinization (AOA) with a scenario based on the Representative Concentration Pathway (RCP) framework. Addition of 114 Pmol of alkalinity to the surface ocean stabilizes atmospheric CO2 concentration to RCP4.5 levels under RCP8.5 emissions. This scenario removes 940 GtC from the atmosphere and mitigates 1.5 K of global warming within this century. The climate adjusts to the lower CO2 concentration preventing the loss of sea ice and high sea level rise. Seawater pH and the carbonate saturation state (Ω) rise substantially above levels of the current decade. Pronounced differences in regional sensitivities to AOA are projected, with the Arctic Ocean and tropical oceans emerging as hot spots for biogeochemical changes induced by AOA. Thus, the CO2 mitigation potential of AOA comes at a price of an unprecedented ocean biogeochemistry perturbation with unknown ecological consequences.

Ionomic and metabolic responses to neutral salt or alkaline salt stresses in maize (Zea mays L.) seedlings.

PubMed

Guo, Rui; Shi, LianXuan; Yan, Changrong; Zhong, Xiuli; Gu, FengXue; Liu, Qi; Xia, Xu; Li, Haoru

2017-02-10

Soil salinity and alkalinity present a serious threat to global agriculture. However, most of the studies have focused on neutral salt stress, and the information on the metabolic responses of plants to alkaline salt stress is limited. This investigation aimed at determining the influence of neutral salt and alkaline salt stresses on the content of metal elements and metabolites in maize plant tissues, by using mixtures of various proportions of NaCl, NaHCO 3 , Na 2 SO 4 , and Na 2 CO 3 . We found that alkaline salt stress suppressed more pronouncedly the photosynthesis and growth of maize plants than salinity stress. Under alkaline salt stress conditions, metal ions formed massive precipitates, which ultimately reduced plant nutrient availability. On the other hand, high neutral salt stress induced metabolic changes in the direction of gluconeogenesis leading to the enhanced formation of sugars as a reaction contributing to the mitigation of osmotic stress. Thus, the active synthesis of sugars in shoots was essential to the development of salt tolerance. However, the alkaline salt stress conditions characterized by elevated pH values suppressed substantially the levels of photosynthesis, N metabolism, glycolysis, and the production of sugars and amino acids. These results indicate the presence of different defensive mechanisms responsible for the plant responses to neutral salt and alkaline salt stresses. In addition, the increased concentration of organic acids and enhanced metabolic energy might be potential major factors that can contribute to the maintenance intracellular ion balance in maize plants and counteract the negative effects of high pH under alkaline salt stress.

Bone mineral density and metabolic indices in hyperthyroidism.

PubMed

Al-Nuaim, A; El-Desouki, M; Sulimani, R; Mohammadiah, M

1991-09-01

Hyperthyroidism can alter bone metabolism by increasing both bone resorption and formation. The increase in bone resorption predominates, leading to a decrease in bone mass. To assess the effect of hyperthyroidism on bone and mineral metabolism, we measured bone density using single photon absorptiometry in 30 untreated hyperthyroid patients. Patients were categorized into three groups based on sex and alkaline phosphatase levels: 44 sex- and age-matched subjects were used as controls. Bone densities were significanlty lower in all patient groups compared with controls. Alkaline phosphatase was found to be a useful marker for assessing severity of bone disease in hyperthyroid patients as there is significant bone density among patients with higher alkaline phosphatase value. Hyperthyroidism should be considered in the differential diagnosis of unexplained alkaline phophatase activity.

Altered skeletal pattern of gene expression in response to spaceflight and hindlimb elevation

NASA Technical Reports Server (NTRS)

Bikle, D. D.; Harris, J.; Halloran, B. P.; Morey-Holton, E.

1994-01-01

Spaceflight leads to osteopenia, in part by inhibiting bone formation. Using an animal model (hindlimb elevation) that simulates the weightlessness of spaceflight, we and others showed a reversible inhibition of bone formation and bone mineralization. In this study, we have measured the mRNA levels of insulin-like growth factor I (IGF-I), IGF-I receptor (IGF-IR), alkaline phosphatase, and osteocalcin in the tibiae of rats flown aboard National Aeronautics and Space Administration Shuttle Flight STS-54 and compared the results with those obtained from their ground-based controls and from the bones of hindlimb-elevated animals. Spaceflight and hindlimb elevation transiently increase the mRNA levels for IGF-I, IGF-IR, and alkaline phosphatase but decrease the mRNA levels for osteocalcin. The changes in osteocalcin and alkaline phosphatase mRNA levels are consistent with a shift toward decreased maturation, whereas the rise in IGF-I and IGF-IR mRNA levels may indicate a compensatory response to the fall in bone formation. We conclude that skeletal unloading during spaceflight or hindlimb elevation resets the pattern of gene expression in the osteoblast, giving it a less mature profile.

Extracellular Alkalinization as a Defense Response in Potato Cells.

PubMed

Moroz, Natalia; Fritch, Karen R; Marcec, Matthew J; Tripathi, Diwaker; Smertenko, Andrei; Tanaka, Kiwamu

2017-01-01

A quantitative and robust bioassay to assess plant defense response is important for studies of disease resistance and also for the early identification of disease during pre- or non-symptomatic phases. An increase in extracellular pH is known to be an early defense response in plants. In this study, we demonstrate extracellular alkalinization as a defense response in potatoes. Using potato suspension cell cultures, we observed an alkalinization response against various pathogen- and plant-derived elicitors in a dose- and time-dependent manner. We also assessed the defense response against a variety of potato pathogens, such as protists ( Phytophthora infestans and Spongospora subterranea ) and fungi ( Verticillium dahliae and Colletotrichum coccodes ). Our results show that extracellular pH increases within 30 min in proportion to the number of pathogen spores added. Consistently with the alkalinization effect, the higher transcription level of several defense-related genes and production of reactive oxygen species was observed. Our results demonstrate that the alkalinization response is an effective marker to study early stages of defense response in potatoes.

Enhanced production of alkaline thermostable keratinolytic protease from calcium alginate immobilized cells of thermoalkalophilic Bacillus halodurans JB 99 exhibiting dehairing activity.

PubMed

Shrinivas, Dengeti; Kumar, Raghwendra; Naik, G R

2012-01-01

The thermoalkalophilic Bacillus halodurans JB 99 cells known for production of novel thermostable alkaline keratinolytic protease were immobilized in calcium alginate matrix. Batch and repeated batch cultivation using calcium alginate immobilized cells were studied for alkaline protease production in submerged fermentation. Immobilized cells with 2.5% alginate and 350 beads/flask of initial cell loading showed enhanced production of alkaline protease by 23.2% (5,275 ± 39.4 U/ml) as compared to free cells (4,280 ± 35.4 U/ml) after 24 h. In the semicontinuous mode of cultivation, immobilized cells under optimized conditions produced an appreciable level of alkaline protease in up to nine cycles and reached a maximal value of 5,975 U/ml after the seventh cycle. The enzyme produced from immobilized cells efficiently degraded chicken feathers in the presence of a reducing agent which can help the poultry industry in the management of keratin-rich waste and obtaining value-added products.

Metabolic profiling studies on the toxicological effects of realgar in rats by {sup 1}H NMR spectroscopy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wei Lai; Liao Peiqiu; Wu Huifeng

2009-02-01

The toxicological effects of realgar after intragastrical administration (1 g/kg body weight) were investigated over a 21 day period in male Wistar rats using metabonomic analysis of {sup 1}H NMR spectra of urine, serum and liver tissue aqueous extracts. Liver and kidney histopathology examination and serum clinical chemistry analyses were also performed. {sup 1}H NMR spectra and pattern recognition analyses from realgar treated animals showed increased excretion of urinary Kreb's cycle intermediates, increased levels of ketone bodies in urine and serum, and decreased levels of hepatic glucose and glycogen, as well as hypoglycemia and hyperlipoidemia, suggesting the perturbation of energymore » metabolism. Elevated levels of choline containing metabolites and betaine in serum and liver tissue aqueous extracts and increased serum creatine indicated altered transmethylation. Decreased urinary levels of trimethylamine-N-oxide, phenylacetylglycine and hippurate suggested the effects on the gut microflora environment by realgar. Signs of impairment of amino acid metabolism were supported by increased hepatic glutamate levels, increased methionine and decreased alanine levels in serum, and hypertaurinuria. The observed increase in glutathione in liver tissue aqueous extracts could be a biomarker of realgar induced oxidative injury. Serum clinical chemistry analyses showed increased levels of lactate dehydrogenase, aspartate aminotransferase, and alkaline phosphatase as well as increased levels of blood urea nitrogen and creatinine, indicating slight liver and kidney injury. The time-dependent biochemical variations induced by realgar were achieved using pattern recognition methods. This work illustrated the high reliability of NMR-based metabonomic approach on the study of the biochemical effects induced by traditional Chinese medicine.« less

Production optimization of a heat-tolerant alkaline pectinase from Bacillus subtilis ZGL14 and its purification and characterization.

PubMed

Yu, Ping; Zhang, Yishu; Gu, Donglu

2017-09-03

Alkaline pectinase has important applications in the pretreatment of waste water from food processing and in both the fabric and paper industries. In this study, a 2-level factorial design was used to screen significant factors that affect the activity of alkaline pectinase, and the response surface methodology (RSM) with a Box-Behnken design (BBD) was used to optimize their concentrations. Starch, peptone, KH 2 PO 4 and K 2 HPO 4 ·3H 2 O were found to significantly affect the activity of alkaline pectinase. Their optimal concentrations were as follows: 4.68% starch, 1.6% peptone, 0.26% KH 2 PO 4 and 0.68% K 2 HPO 4 ·3H 2 O. Under the above conditions, the activity of alkaline pectinase was significantly improved to 734.11 U/mL. Alkaline pectinase was purified to homogeneity with a recovery rate of 9.6% and a specific activity of 52372.52 U/mg. Its optimal temperature and pH were 50°C and 8.6, respectively. The purified enzyme showed strong thermo-stability and good alkali resistance. In addition, the activity of alkaline pectinase was improved in the presence of Mg 2+ . Cu 2+ , Mn 2+ , and Co 2+ significantly inhibited its activity. This study provides an important basis for the future development and use of a heat-tolerant alkaline pectinase from B. subtilis ZGL14.

Production optimization of a heat-tolerant alkaline pectinase from Bacillus subtilis ZGL14 and its purification and characterization

PubMed Central

Yu, Ping; Zhang, Yishu; Gu, Donglu

2017-01-01

ABSTRACT Alkaline pectinase has important applications in the pretreatment of waste water from food processing and in both the fabric and paper industries. In this study, a 2-level factorial design was used to screen significant factors that affect the activity of alkaline pectinase, and the response surface methodology (RSM) with a Box-Behnken design (BBD) was used to optimize their concentrations. Starch, peptone, KH2PO4 and K2HPO4·3H2O were found to significantly affect the activity of alkaline pectinase. Their optimal concentrations were as follows: 4.68% starch, 1.6% peptone, 0.26% KH2PO4 and 0.68% K2HPO4·3H2O. Under the above conditions, the activity of alkaline pectinase was significantly improved to 734.11 U/mL. Alkaline pectinase was purified to homogeneity with a recovery rate of 9.6% and a specific activity of 52372.52 U/mg. Its optimal temperature and pH were 50°C and 8.6, respectively. The purified enzyme showed strong thermo-stability and good alkali resistance. In addition, the activity of alkaline pectinase was improved in the presence of Mg2+. Cu2+, Mn2+, and Co2+ significantly inhibited its activity. This study provides an important basis for the future development and use of a heat-tolerant alkaline pectinase from B. subtilis ZGL14. PMID:28282260

Proteomic analysis of enterotoxigenic Escherichia coli (ETEC) in neutral and alkaline conditions.

PubMed

Gonzales-Siles, Lucia; Karlsson, Roger; Kenny, Diarmuid; Karlsson, Anders; Sjöling, Åsa

2017-01-07

Enterotoxigenic Escherichia coli (ETEC) is a major cause of diarrhea in children and travelers to endemic areas. Secretion of the heat labile AB 5 toxin (LT) is induced by alkaline conditions. In this study, we determined the surface proteome of ETEC exposed to alkaline conditions (pH 9) as compared to neutral conditions (pH 7) using a LPI Hexalane FlowCell combined with quantitative proteomics. Relative quantitation with isobaric labeling (TMT) was used to compare peptide abundance and their corresponding proteins in multiple samples at MS/MS level. For protein identification and quantification samples were analyzed using either a 1D-LCMS or a 2D-LCMS approach. Strong up-regulation of the ATP synthase operon encoding F1Fo ATP synthase and down-regulation of proton pumping proteins NuoF, NuoG, Ndh and WrbA were detected among proteins involved in regulating the proton and electron transport under alkaline conditions. Reduced expression of proteins involved in osmotic stress was found at alkaline conditions while the Sec-dependent transport over the inner membrane and outer membrane protein proteins such as OmpA and the β-Barrel Assembly Machinery (BAM) complex were up-regulated. ETEC exposed to alkaline environments express a specific proteome profile characterized by up-regulation of membrane proteins and secretion of LT toxin. Alkaline microenvironments have been reported close to the intestinal epithelium and the alkaline proteome may hence represent a better view of ETEC during infection.

Online monitoring of electrocatalytic reactions of alcohols at platinum and gold electrodes in acidic, neutral and alkaline media by capillary electrophoresis with contactless conductivity detection (EC-CE-C4 D).

PubMed

Ferreira Santos, Mauro Sérgio; Silva Lopes, Fernando; Gutz, Ivano Gebhardt Rolf

2017-11-01

An EC-CE-C 4 D flow system was applied to the investigation of electrocatalytic processes by monitoring carboxylic acids formed during the electro-oxidation at various potentials of primary alcohols (mixture of 1 mmol/L of ethanol, n-propanol, n-butanol and n-pentanol) in acidic, neutral and alkaline media. The electro-oxidation was carried out on gold and platinum disk electrodes (3 mm of diameter) in a thin-layer electrochemical flow cell. Products were sampled 50 μm apart from the electrode directly into the capillary. All the generated carboxylates were determined in near real time (less than 2 min) by CE-C 4 D in counter-flow mode, with Tris/HCl buffer solution (pH 8.6) as BGE. Long sequences of 5-min experiments were run automatically, exploring the applied potential, electrolysis time and solution composition. Electro-oxidation at 1.5 V (versus Ag/AgCl quasi-reference) during 50 s in acidic medium was found appropriate for both Pt and Au electrodes when the determination of alcohols after derivatization is intended. A noteworthy selectivity effect was observed on the Au electrode. The signal corresponding to pentanoate is similar on both electrodes while the signal of ethanoate (acetate) is four times larger on gold than on platinum. The carboxylate signals were lower in alkaline medium (below the determination limit on Pt) than in acidic and neutral media. On gold, the formation of carboxylates was anticipated (0.85 V in alkaline medium versus 1.40 V in neutral medium). The automatic online monitoring of electrochemical processes by EC-CE-C 4 D holds great potential to investigate ionic/ionizable intermediates/products of new electrocatalysts and/or alternative fuels. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Impacts of Priming with Silicon on the Growth and Tolerance of Maize Plants to Alkaline Stress.

PubMed

Abdel Latef, Arafat A; Tran, Lam-Son P

2016-01-01

Silicon (Si) has been known to augment plant defense against biotic and abiotic pressures. Maize (Zea maize L.) is classified as a Si accumulator and is relatively susceptible to alkaline stress. In this study, seeds of maize were grown in pots and exposed to various concentrations of Na2CO3 (0, 25, 50, and 75 mM) with or without 1.5 mM Si in the form of sodium metasilicate Na2O3Si.5H2O for 25 days. Alkaline-stressed plants showed a decrease in growth parameters, leaf relative water content (LRWC), and the contents of photosynthetic pigments, soluble sugars, total phenols and potassium ion (K(+)), as well as potassium/sodium ion (K(+)/Na(+)) ratio. By contrast, alkaline stress increased the contents of soluble proteins, total free amino acids, proline, Na(+) and malondialdehyde (MDA), as well as the activities of superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) in stressed plants. On the other hand, application of Si by seed-priming improved growth of stressed plants, which was accompanied by the enhancement in LRWC, and levels of photosynthetic pigments, soluble sugars, soluble proteins, total free amino acids and K(+), as well as activities of SOD, CAT, and POD enzymes. Furthermore, Si supplement resulted in a decrease in the contents of proline, MDA and Na(+), which together with enhanced K(+) level led to a favorable adjustment of K(+)/Na(+) ratio, in stressed plants relative to plants treated with alkaline stress alone. Taken together, these results indicate that Si plays a pivotal role in alleviating the negative effects of alkaline stress on maize growth by improving water status, enhancing photosynthetic pigments, accumulating osmoprotectants rather than proline, activating the antioxidant machinery, and maintaining the balance of K(+)/Na(+) ratio. Thus, our findings demonstrate that seed-priming with Si is an efficient strategy that can be used to boost tolerance of maize plants to alkaline stress.

Accuracy of the evaluation method for alkaline agents’ bactericidal efficacies in solid, and the required time of bacterial inactivation

PubMed Central

HAKIM, Hakimullah; TOYOFUKU, Chiharu; OTA, Mari; SUZUKI, Mayuko; KOMURA, Miyuki; YAMADA, Masashi; ALAM, Md. Shahin; SANGSRIRATANAKUL, Natthanan; SHOHAM, Dany; TAKEHARA, Kazuaki

2016-01-01

An alkaline agent, namely food additive grade calcium hydroxide (FdCa (OH)2) in the powder form, was evaluated for its bactericidal efficacies in chicken feces at pH 13. The point for this evaluation was neutralization of the alkaline agent’s pH at the time of bacterial recovery, since otherwise the results are substantially misleading. Without neutralization of the FdCa (OH)2 pH, the spiked bacteria were killed within min at the time of recovery in aqueous phase, but not in the solid form in feces, hence, it has been demonstrated that when bacteria were in solid, it took longer time than in liquid for the alkaline agent to inactivate them down to the acceptable level (≥3 log10 CFU/ml). PMID:27890906

Is alkaline phosphatase the smoking gun for highly refractory primitive leukemic cells?

PubMed Central

Rico, Laura G.; Juncà, Jordi; Ward, Mike D.; Bradford, Jolene; Petriz, Jordi

2016-01-01

With the aim to detect candidate malignant primitive progenitor populations, we modified an original alkaline phosphatase (ALP) stem cell detection method based on the identification of alkaline phosphatase fluorescent cells in combination with flow cytometry immunophenotyping. Over a period of one year, we have been using this technique to study its activity in patients with leukemia and lymphoma, showing that changes in the alkaline phosphatase levels can be used to detect rare populations of highly refractory malignant cells. By screening different blood cancers, we have observed that this activity is not always restricted to CD34+ leukemic cells, and can be overexpressed in CD34 negative leukemia. We have verified that this method gives accurate and reproducible measurements and our preliminary results suggest that CD34+/ALPhigh cells appear to sustain leukemogenesis over time. PMID:27732563

Performance and application of a fluidized bed limestone reactor designed for control of alkalinity, hardness and pH at the Warm Springs Regional Fisheries Center

USDA-ARS?s Scientific Manuscript database

Springs serving the Warm Springs Regional Fisheries Center, Warm Springs, Georgia, have pH, alkalinity, and hardness levels that lie under the range required for successful fish propagation while free CO2 is well above allowable targets. We evaluate a pretreatment process that exploits limestone's (...

Chemical composition and variability of the waters of the Edwards Plateau, central Texas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Groeger, A.W.; Gustafson, J.J.

1994-12-31

The surface waters of the karstic Edwards Plateau, southcentral Texas, are quite similar in many of their chemical characteristics. The ionic composition of the water was dominated by calcium and alkalinity (mostly bicarbonate) acquired through limestone weathering, and the ionic composition (in equivalents) was Ca>Mg>Na>K and alkalinity >Cl and SO{sub 4}. The median specific conductance and total dissolved solids ranged from 394 to 535 {mu}S cm{sup {minus}1} and 220 and 327 mg L{sup {minus}1}, respectively. The streams were always near or at supersaturation with respect to calcium carbonate, and the dynamics of calcium carbonate dissolution and precipitation tended to maintainmore » the dissolved substances at a fairly constant level. This may have been enhanced by the intimate contact of water and bedrock characteristic of karst drainages. Specific conductance, Ca, and alkalinity all decreased at higher summer temperatures. Many of the streams on the plateau maintained a constant level or actually increased concentrations of total dissolved substances at increased flow rates. These waters acquired significant quantities of solute as they flow through the confine Edwards Aquifer, including alkalinity, Ca, Mg, Na, Cl, and NO{sub 3}.« less

Use of CAS in Secondary School: A Factor Influencing the Transition to University-Level Mathematics?

ERIC Educational Resources Information Center

Varsavsky, Cristina

2012-01-01

Australian secondary school systems offer three levels of senior (year 12) mathematics studies, none of them compulsory: elementary, intermediate and advanced. The intermediate and advanced studies prepare students for further mathematics studies at university level. In the state of Victoria, there are two versions of intermediate mathematics: one…

49 CFR Figure 2b to Subpart B of... - Example of an Intermediate Level Seating Area of a Multi-Level Car Complying With Window Location...

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Example of an Intermediate Level Seating Area of a Multi-Level Car Complying With Window Location Requirements-§§ 238.113 and 238.114 2B Figure 2B to... Intermediate Level Seating Area of a Multi-Level Car Complying With Window Location Requirements—§§ 238.113 and...

49 CFR Figure 2a to Subpart B of... - Example of an Intermediate Level Seating Area of a Multi-Level Car Complying With Window Location...

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Example of an Intermediate Level Seating Area of a Multi-Level Car Complying With Window Location Requirements-§§ 238.113 and 238.114 2A Figure 2A to... Intermediate Level Seating Area of a Multi-Level Car Complying With Window Location Requirements—§§ 238.113 and...

The multistage crystallization of zircon in calc-alkaline granitoids: U-Pb age constraints on the timing of Variscan tectonic activity in SW Iberia

NASA Astrophysics Data System (ADS)

Pereira, M. F.; Chichorro, M.; Moita, P.; Santos, J. F.; Solá, A. M. R.; Williams, I. S.; Silva, J. B.; Armstrong, R. A.

2015-07-01

CL imaging and U-Th-Pb data for a population of zircons from two of the Évora Massif granitoids (Ossa-Morena Zone, SW Iberia) show that both calc-alkaline granitoids have zircon populations dominated by grains with cores and rims either showing or not showing differences in Th/U ratio, and having ages in the range ca. 350-335 Ma (Early Carboniferous). Multistage crystallization of zircon is revealed in two main growth stages (ca. 344-342 Ma and ca. 336-335 Ma), well represented by morphologically complex zircons with cores and rims with different ages and different Th/U ratios that can be explained by: (1) crystallization from melts with different compositions (felsic peraluminous to felsic-intermediate metaluminous; 0.001 < Th/U ratio < 0.5) and (2) transient temperature fluctuations in a system where anatectic felsic melts periodically underwent injection of more mafic magmas at higher temperatures. The two studied calc-alkaline granitoids do not include inherited zircons (pre-Carboniferous), probably because they were formed at the highest grade of metamorphism ( T > 837 °C; granulite facies) and/or because they were derived from inheritance-poor felsic and mafic rocks from a previous cycle, as suggested by the internal structures of zircon cores. These Variscan magmatic rocks with crystallization ages estimated at ca. 336-335 Ma are spatially and temporally related to high-temperature metamorphism, anatexis, processes of interaction between crustal- and mantle-derived magmas and intra-orogenic extension that acted in SW Iberia during the Early Carboniferous.

The effect of metal salts on the decomposition of sweet sorghum bagasse in flow-through liquid hot water.

PubMed

Yu, Qiang; Zhuang, Xinshu; Yuan, Zhenhong; Qi, Wei; Wang, Qiong; Tan, Xuesong

2011-02-01

The impact of the metal salts NaCl, KCl, CaCl(2), MgCl(2), FeCl(3), FeCl(2), and CuCl(2), particularly the latter, on the decomposition of hemicellulose and lignin from sweet sorghum bagasse in liquid hot water pretreatment processing was studied in an attempt to enhance the recovery of sugars. Transition metal chlorides significantly enhanced the hemicellulose removal compared to the alkaline earth metal chlorides and alkaline metal chlorides, contributing to the formation of a saccharide-metal cation intermediate complex. FeCl(2) greatly increased xylose degradation and about 60% xylan was converted into non-saccharide products. In contrast, an excellent total and monomeric xylose recovery was obtained after the CuCl(2) pretreatment. Most of the lignin was deposited on the surface of the residual solid with droplet morphologies after this pretreatment, and about 20% was degraded into monomeric products. The total recovery of sugars from sweet sorghum bagasse with 0.1% CuCl(2) solution pretreatment and 48 h enzymatic digestibility, reached 90.4%, which is superior to the recovery using hot water pretreatment only. Copyright © 2010 Elsevier Ltd. All rights reserved.

Alkali and alkaline earth metal salts of tetrazolone: structurally interesting and excellently thermostable.

PubMed

He, Piao; Wu, Le; Wu, Jin-Ting; Yin, Xin; Gozin, Michael; Zhang, Jian-Guo

2017-07-04

Tetrazolone (5-oxotetrazole) was synthesized by a moderate strategy through three steps (addition, cyclization and catalytic hydrogenation) avoiding the unstable intermediate diazonium, as reported during the previous preparation. Alkali and alkaline earth metal salts with lithium (1), sodium (2), potassium (3), rubidium (4) caesium (5), magnesium (6), calcium (7), strontium (8) and barium (9) were prepared and fully characterized using elemental analysis, IR and NMR spectroscopy, DSC and TG analysis. All metal salts were characterized via single-crystal X-ray diffraction. They crystallize in common space groups with high densities ranging from 1.479 (1) to 3.060 g cm -3 (5). Furthermore, the crystal structures of 7, 8 and 9 reveal interesting porous energetic coordination polymers with strong hydrogen bond interactions. All new salts have good thermal stabilities with decomposition temperature between 215.0 °C (4) and 328.2 °C (7), significantly higher than that of the reported nitrogen-rich salt neutral tetrazolone. The sensitivities towards impact and friction were tested using standard methods, and all the tetrazolone-based compounds investigated can be classified into insensitive. The flame test of these metal salts supports their potential use as perchlorate-free pyrotechnics or eco-friendly insensitive energetic materials.

Geothermal activity and hydrothermal mineral deposits at southern Lake Bogoria, Kenya Rift Valley: Impact of lake level changes

NASA Astrophysics Data System (ADS)

Renaut, Robin W.; Owen, R. Bernhart; Ego, John K.

2017-05-01

Lake Bogoria, a saline alkaline closed-lake in a drainage basin of Neogene volcanic rocks in the central Kenya Rift, is fed partly by ∼200 hot alkaline springs located in three groups along its margins. Hot springs along the midwest shoreline (Loburu, Chemurkeu) and their travertine deposits have been studied, but little is known about the geothermal activity at southern Lake Bogoria. Observations, field measurements and analyses (geochemical and mineralogical) of the spring waters and deposits, spanning three decades, show that the southern spring waters are more saline, the hydrothermal alteration there is more intense, and that most hot spring deposits are siliceous. Geothermal activity at southern Lake Bogoria (Ng'wasis, Koibobei, Losaramat) includes littoral boiling springs and geysers, with fumaroles at slightly higher elevations. Modern spring deposits are ephemeral sodium carbonates, opal-A crusts and silica gels. Local fossil spring deposits include diatomaceous silica-cemented conglomerates that formed subaqueously when the lake was then dilute and higher than today, and outlying calcite tufa deposits. In contrast, mineral deposits around neighbouring fumarole vents and sites of hydrothermal alteration include clays (kaolinite), sulfate minerals (jarosite, alunite), and Fe-oxyhydroxides linked to rising acidic fluids. When lake level falls, the zone of acidity moves downwards and may overprint older alkaline spring deposits. In contrast, rising lake level leads to lake water dilution and vents in the lower parts of the acidic zone may become dilute alkaline springs. The new evidence at Lake Bogoria shows the potential for using the mineralogy of geothermal sediments to indicate former changes in lake level.

Photocatalytic degradation kinetics and mechanism of phenobarbital in TiO(2) aqueous solution.

PubMed

Cao, Hua; Lin, Xiulian; Zhan, Haiying; Zhang, Hong; Lin, Jingxin

2013-01-01

5-Ethyl-5-phenylpyrimidine-2,4,6(1H, 3H, 5H)-trione is an anti-convulsant used to treat disorders of movement, e.g. tremors. This work deals with the transformation of phenobarbital by UV/TiO(2) heterogeneous photocatalysis, to assess the decomposition of the pharmaceutical compound, to identify intermediates, as well as to elucidate some mechanistic details of the degradation. The photocatalytic removal efficiency of 100 μm phenobarbital is about 80% within 60 min, while the degradation efficiency of phenobarbital was better in alkaline solution. The study on contribution of reactive oxidative species (ROSs) has shown that ()OH is responsible for the major degradation of phenobarbital, while the photohole, photoelectrons and the other ROSs have the minor contribution to the degradation. Finally, based on the identification of degradation intermediates, two main photocatalytic degradation pathways have been tentatively proposed, including the hydroxylation and cleavage of pyrimidine ring in the phenobarbital molecule respectively. Certainly, the phenobarbital can be mineralized when the photocatalytic reaction time prolongs. Copyright © 2012 Elsevier Ltd. All rights reserved.

Amyloidogenic behavior of different intermediate state of stem bromelain: A biophysical insight.

PubMed

Zaman, Masihuz; Ehtram, Aquib; Chaturvedi, Sumit Kumar; Nusrat, Saima; Khan, Rizwan Hasan

2016-10-01

Stem bromelain, a cysteine proteases from Ananas comosus is a widely accepted therapeutic drug with broad medicinal application. It exists as intermediate states at pH 2.0 and 10.0, where it encountered in gastrointestinal tract during adsorption (acidic pH) and in gut epithelium (alkaline pH), respectively. In this study, we monitored the thermal aggregation/amyloid formation of SB at different pH intermediate states. Thermal treatment of stem bromelain at pH 10.0 favors the fibrillation in which the extent of aggregation increases with increase in protein concentration. However, no fibril formation in stem bromelain at pH 2.0 was found at all the concentration used at pH 10.0. The fibril formation was confirmed by various techniques such as turbidity measurements, Rayleigh light scattering, dye binding assays and far UV circular dichroism. The Dynamic light scattering confirmed the formation of aggregates by measuring the hydrodynamic radii pattern. Moreover, microscopic techniques were performed to analyze the morphology of fibrils. The aggregation behavior may be due to variation in number of charged amino acid residues. The less negative charge developed at pH 10.0 may be responsible for aggregation. This work helps to overcome the aggregation related problems of stem bromelain during formulations in pharmaceutical industry. Copyright © 2016 Elsevier B.V. All rights reserved.

Cytoplasmic peptidoglycan intermediate levels in Staphylococcus aureus.

PubMed

Vemula, Harika; Ayon, Navid J; Gutheil, William G

2016-02-01

Intracellular cytoplasmic peptidoglycan (PG) intermediate levels were determined in Staphylococcus aureus during log-phase growth in enriched media. Levels of UDP-linked intermediates were quantitatively determined using ion pairing LC-MS/MS in negative mode, and amine intermediates were quantitatively determined stereospecifically as their Marfey's reagent derivatives in positive mode. Levels of UDP-linked intermediates in S. aureus varied from 1.4 μM for UDP-GlcNAc-Enolpyruvyate to 1200 μM for UDP-MurNAc. Levels of amine intermediates (L-Ala, D-Ala, D-Ala-D-Ala, L-Glu, D-Glu, and L-Lys) varied over a range of from 860 μM for D-Ala-D-Ala to 30-260 mM for the others. Total PG was determined from the D-Glu content of isolated PG, and used to estimate the rate of PG synthesis (in terms of cytoplasmic metabolite flux) as 690 μM/min. The total UDP-linked intermediates pool (2490 μM) is therefore sufficient to sustain growth for 3.6 min. Comparison of UDP-linked metabolite levels with published pathway enzyme characteristics demonstrates that enzymes on the UDP-branch range from >80% saturation for MurA, Z, and C, to <5% saturation for MurB. Metabolite levels were compared with literature values for Escherichia coli, with the major difference in UDP-intermediates being the level of UDP-MurNAc, which was high in S. aureus (1200 μM) and low in E. coli (45 μM). Copyright © 2015 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.

Ethanol production from bamboo using mild alkaline pre-extraction followed by alkaline hydrogen peroxide pretreatment.

PubMed

Yuan, Zhaoyang; Wen, Yangbing; Kapu, Nuwan Sella

2018-01-01

A sequential two-stage pretreatment process comprising alkaline pre-extraction and alkaline hydrogen peroxide pretreatment (AHP) was investigated to convert bamboo carbohydrates into bioethanol. The results showed that mild alkaline pre-extraction using 8% (w/w) sodium hydroxide (NaOH) at 100°C for 180min followed by AHP pretreatment with 4% (w/w) hydrogen peroxide (H 2 O 2 ) was sufficient to generate a substrate that could be efficiently digested with low enzyme loadings. Moreover, alkali pre-extraction enabled the use of lower H 2 O 2 charges in AHP treatment. Two-stage pretreatment followed by enzymatic hydrolysis with only 9FPU/g cellulose led to the recovery of 87% of the original sugars in the raw feedstock. The use of the pentose-hexose fermenting Saccharomyces cerevisiae SR8u strain enabled the utilization of 95.7% sugars in the hydrolysate to reach 4.6%w/v ethanol titer. The overall process also enabled the recovery of 62.9% lignin and 93.8% silica at high levels of purity. Copyright © 2017 Elsevier Ltd. All rights reserved.

The Path of Carbon in Photosynthesis XIII. pH Effects in C{sup 14}O{sub 2} Fixation by Scenedesmus

DOE R&D Accomplishments Database

Ouellet, C.; Benson, A. A.

1951-10-23

The rates of photosynthesis and dark fixation of C{sup 14}O{sub 2} in Scenedesmus have been compared in dilute phosphate buffers of 1.6 to 11.4 pH; determination of C{sup 14} incorporation into the various products shows enhancement of uptake in an acid medium into sucrose, polysaccharides, alanine and serine, in an alkaline medium into malic asparctic acids. kinetic experiments at extreme pH values suggest that several paths are available for CO{sub 2} assimilation. A tentative correlation of the results with the pH optima of some enzymes and resultant effects upon concentrations of intermediates is presented.

Water resources of the White Earth Indian Reservation, northwestern Minnesota

USGS Publications Warehouse

Ruhl, J.F.

1989-01-01

Surface water also is a calcium magnesium bicarbonate type. Lake waters are hard and alkaline and are mesotrophic to eutrophic in productivity. Quality of the lake and stream water is suitable for native forms of freshwater biota, although the concentration of total recoverable mercury exceeds the 0.012 micrograms per liter maximum contaminant level; that level, established by USEPA for the organic form of dissolved mercury, is intended to protect against chronic effects on freshwater life. Available information, however, indicates that the amount of mercury in edible tissue from fish in alkaline lakes of northwestern Minnesota is within safe limits. The concentrations of phosphorus and nitrate in the streams are below levels that indicate pollution problems.

Alkaline Comet Assay for Assessing DNA Damage in Individual Cells.

PubMed

Pu, Xinzhu; Wang, Zemin; Klaunig, James E

2015-08-06

Single-cell gel electrophoresis, commonly called a comet assay, is a simple and sensitive method for assessing DNA damage at the single-cell level. It is an important technique in genetic toxicological studies. The comet assay performed under alkaline conditions (pH >13) is considered the optimal version for identifying agents with genotoxic activity. The alkaline comet assay is capable of detecting DNA double-strand breaks, single-strand breaks, alkali-labile sites, DNA-DNA/DNA-protein cross-linking, and incomplete excision repair sites. The inclusion of digestion of lesion-specific DNA repair enzymes in the procedure allows the detection of various DNA base alterations, such as oxidative base damage. This unit describes alkaline comet assay procedures for assessing DNA strand breaks and oxidative base alterations. These methods can be applied in a variety of cells from in vitro and in vivo experiments, as well as human studies. Copyright © 2015 John Wiley & Sons, Inc.

Theoretical study of the alkaline-earth metal superoxides BeO2 through SrO2

NASA Technical Reports Server (NTRS)

Bauschlicher, Charles W., Jr.; Partridge, Harry; Sodupe, Mariona; Langhoff, Stephen R.

1992-01-01

Three competing bonding mechanisms have been identified for the alkaline-earth metal superoxides: these result in a change in the optimal structure and ground state as the alkaline-earth metal becomes heavier. For example, BeO2 has a linear 3Sigma(-)g ground-state structure, whereas both CaO2 and SrO2 have C(2v)1A1 structures. For MgO2, the theoretical calculations are less definitive, as the 3A2 C(2v) structure is computed to lie only about 3 kcal/mol above the 3Sigma(-)g linear structure. The bond dissociation energies for the alkaline-earth metal superoxides have been computed using extensive Gaussian basis sets and treating electron correlation at the modified coupled-pair functional or coupled-cluster singles and doubles level with a perturbational estimate of the triple excitations.

Juvenile crustal recycling in an accretionary orogen: Insights from contrasting Early Permian granites from central Inner Mongolia, North China

NASA Astrophysics Data System (ADS)

Yuan, Lingling; Zhang, Xiaohui; Xue, Fuhong; Liu, Fulin

2016-11-01

Coeval high-K calc-alkaline to alkaline granites constitute important components of post-collisional to post-orogenic igneous suites in most orogenic belts of various ages on Earth and their genesis harbors a key to ascertaining critical geodynamic controls on continental crustal formation and differentiation. This zircon U-Pb dating and geochemical study documents three contrasting Early Permian granites from Erenhot of central Inner Mongolia, eastern Central Asian Orogenic Belt (CAOB) and reveals concurrent high-K calc-alkaline to alkaline granite association derived from successive partial melting of distinct protoliths. The ca. 280 Ma Gancihuduge (GCG) pluton shows a calc-alkaline I-type character, with initial 87Sr/86Sr ratios of 0.7035 to 0.7039, εNd(t) of + 1.87 to + 4.70, zircon εHf(t) of + 8.0 to + 13.2 and δ18O from 7.4 to 8.7‰. The ca. 276 Ma Cailiwusu (CLS) pluton is magnesian and peraluminous, with initial 87Sr/86Sr ratios of 0.7036 to 0.7040, εNd(t) of + 1.9 to + 2.4, zircon εHf(t) of + 6.5 to + 12.1 and δ18O from 9.7 to 10.9‰. These features are consistent with partial melts of mixed sources composed of newly underplated meta-basaltic to -andesitic protoliths and variable supracrustal components, with distinctively higher proportion of the latter in the CLS pluton. By contrast, the ca. 279 Ma Kunduleng (KDL) suite exhibits an A-type magmatic affinity, with typical enrichment in alkalis, Ga, Zr, Nb and Y, εNd(t) of + 2.39 to + 3.55, zircon εHf(t) from + 8.3 to + 12.3 and δ18O values from 6.8 to 7.5‰. These features suggest that they stem from high-temperature fusion of dehydrated K-rich mafic to intermediate protoliths. Besides presenting a snapshot into a stratified crustal architecture in δ18O, these contrasting granites could not only serve as a temporal marker for monitoring post-collisional extension in the aftermath of a retreating subduction zone, but also present spatial magmatic proxy for tracing crustal formation and differentiation within back-arc basin environments in the CAOB.

Instability diagnosis and syntrophic acetate oxidation during thermophilic digestion of vegetable waste.

PubMed

Li, Dong; Ran, Yi; Chen, Lin; Cao, Qin; Li, Zhidong; Liu, Xiaofeng

2018-08-01

Effective process monitoring and instability diagnosis are important for stable anaerobic digestion (AD) of vegetable waste (VW). In order to evaluate the performance of thermophilic digestion of VW, to make early diagnosis for instability after organic overload, and to reveal the dynamics of microbial community under different running states, thermophilic AD of VW was carried out under improved organic loading rates (OLR) of 0.5-2.5 g volatile solid (VS)/(L ∙ d) in this study. Gaseous parameters including volumetric methane production rate (VMPR), CH 4 , CO 2 , and H 2 concentrations, and liquid parameters including pH, oxidation-reduction potential, volatile fatty acid (VFA), and total alkalinity (TA), bicarbonate alkalinity (BA), intermediate alkalinity (IA), and ammonia, were monitored. The coupling parameters, such as the CH 4 /CO 2 , VFA/BA, and BA/TA ratios were also used to evaluate stability. The dynamics of syntrophic acetate-oxidizing bacteria (SAOB), acetoclastic methanogens (AM), and hydrogenotrophic methanogens (HM) were analyzed by high-throughput sequencing. The main methanogenic bacteria were HM (Methanothermobacter) during the start-up period of OLR 0.5 gVS/(L ∙ d), while they were AM (Methanosarcina) during the stable period of OLR of 1.0 gVS/(L ∙ d). The VMPR of stable period was about 0.29 L/(L · d) with total VFA concentration below 100 mg/L, CH 4 /CO 2  > 1.3, and BA/TA>0.9. The first instability due to the accumulation of VFA and self-recovery due to syntrophic acetate oxidation occurred at an OLR of 1.5 gVS/(L ∙ d). The syntrophic acetate-oxidizing bacteria probably belong to genus S1 (family Thermotogaceae). The digestion failed at an OLR of 2.0 g VS/(L · d). H 2 was only detected during collapsed period instead of instable period. The total ammonia nitrogen loss and bicarbonate alkalinity (BA) reduction were the primary causes for the instability of AD of VW without effluent recirculation. Compared with single parameters, the CH 4 /CO 2 and BA/total alkalinity (TA) ratios are recommended as early warning indicators for engineering applications of thermophilic AD of VW. Copyright © 2018 Elsevier Ltd. All rights reserved.

The physiology of the Tambaqui (Colossoma macropomum) at pH 8.0.

PubMed

Wood, Chris M; Gonzalez, R J; Ferreira, Márcio Soares; Braz-Mota, Susana; Val, Adalberto Luis

2018-05-01

The Tambaqui is a model neotropical teleost which is of great economic and cultural importance in artisanal fisheries and commercial aquaculture. It thrives in ion-poor, often acidic Amazonian waters and exhibits excellent regulation of physiology down to water pH 4.0. Curiously, however, it is reported to perform poorly in aquaculture at pH 8.0, an only slightly alkaline pH which would be benign for most freshwater fish. In initial experiments with Tambaqui of intermediate size (30-50 g), we found that ammonia excretion rate was unchanged at pH 4, 5, 6, and 7, but elevated after 20-24 h at pH 8, exactly opposite the pattern seen in most teleosts. Subsequent experiments with large Tambaqui (150-300 g) demonstrated that only ammonia, and not urea excretion was increased at pH 8.0, and that the elevation was proportional to a general increase in MO 2 . There was an accompanying elevation in net acidic equivalent excretion and/or basic equivalent uptake which occurred mainly at the gills. Net Na + balance was little affected while Cl - balance became negative, implicating a disturbance of Cl - versus base exchange rather than Na + versus acid exchange. Arterial blood pH increased by 0.2 units at pH 8.0, reflecting combined metabolic and respiratory alkaloses. Most parameters recovered to control levels by 18-24 h after return to pH 6.0. With respect to large Tambaqui, we conclude that a physiology adapted to acidic pH performs inappropriately at moderately alkaline pH. In small Tambaqui (4-15 g), the responses were very different, with an initial inhibition of ammonia excretion rate at pH 8.0 followed by a subsequent restoration of control levels. Elevated ammonia excretion rate occurred only after return to pH 6.0. Furthermore, MO 2 , plasma cortisol, and branchial vH + ATPase activities all declined during pH 8.0 exposure in small Tambaqui, in contrast to the responses in larger fish. Overall, small Tambaqui appear to cope better at pH 8.0, a difference that may correlate with their natural history in the wild.

[Stakeholder representations of the role of the intermediate level of the DRC health system].

PubMed

Mbeva, Jean Bosco Kahindo; Karemere, Hermès; Schirvel, Carole; Porignon, Denis

2014-01-01

Intermediate health care structures in the DRC were designed during the setting-up of primary health care in a perspective of health district support. This study was designed to describe stakeholder representations of the intermediate level of the DRC health system during the first 30 years of the primary health care system. This case study was based on inductive analysis of data from 27 key informant interviews.. The intermediate level of the health system, lacking sufficient expertise and funding during the 1980s, was confined to inspection and control functions, answering to the central level of the Ministry of health and provincial authorities. Since the 1990s, faced with the pressing demand for support from health district teams, whose self-management had to deal with humanitarian emergencies, the need to integrate vertical programmes, and cope with the logistics of many different actors, the intermediate heath system developed methods and tools to support heath districts. This resulted in a subsidiary model of the intermediate level, the perceived efficacy of which varies according to the province over recent years. The "subsidiary" model of the intermediary health system level seems a good alternative to the "control" model in DRC.

Effect of an alkaline environment on the engineering behavior of cement-stabilized/solidified Zn-contaminated soils.

PubMed

Liu, Jingjing; Zha, Fusheng; Deng, Yongfeng; Cui, Kerui; Zhang, Xueqin

2017-12-01

Although the stabilization/solidification method has been widely used for remediation of heavy metal-contaminated soils in recent decades, the engineering behavior and mobility of heavy metal ions under alkaline groundwater conditions are still unclear. Therefore, the unconfined compressive strength test (UCS) combined with toxicity characteristic leaching procedure (TCLP) and general acid neutralization capacity (GANC) was used to investigate the effects of alkalinity (using NaOH to simulate alkalinity in the environment) on the mechanical and leaching characteristics of cement-solidified/stabilized (S/S) Zn-contaminated soils. Moreover, the microstructure was analyzed using the scanning electron microscope (SEM) technology. The results indicated that alkaline environment could accelerate the UCS development compared with specimens without soaking in NaOH solution,, regardless of whether the specimens contained Zn 2+ or not. And the UCS varied obviously attributed to the variations of both NaOH concentration and soaking time. Except for the specimens soaked for 90 days, the leached Zn 2+ concentrations were higher than that of without soaking. However, the leachability of Zn 2+ in all the stabilized specimens is in the regulatory level. ANC results indicated that the Zn 2+ leaching behavior can be divided into three stages related to the initial leachate pH. Moreover, SEM results proved that the alkaline environment could actually facilitate the cement hydration process. The results proved in the present paper could be useful in treating the heavy metal-contaminated soils involved in the solidification/stabilization technology under alkaline environment.

Electronic and magnetic properties of RMnO3/AMnO3 heterostructures

NASA Astrophysics Data System (ADS)

Yu, Rong; Yunoki, Seiji; Dong, Shuai; Dagotto, Elbio

2009-09-01

The ground-state properties of RMnO3/AMnO3 (RMO/AMO) heterostructures (with R=La,Pr,… , a trivalent rare-earth cation and A=Sr,Ca,… , a divalent alkaline cation) are studied using a two-orbital double-exchange model including the superexchange coupling and Jahn-Teller lattice distortions. To describe the charge transfer across the interface, the long-range Coulomb interaction is taken into account at the mean-field level, by self-consistently solving the Poisson’s equation. The calculations are carried out numerically on finite clusters. We find that the state stabilized near the interface of the heterostructure is similar to the state of the bulk compound (R,A)MO at electronic density close to 0.5. For instance, a charge and orbitally ordered CE state is found at the interface if the corresponding bulk (R,A)MO material is a narrow-to-intermediate bandwidth manganite. But instead the interface regime accommodates an A-type antiferromagnetic state with a uniform x2-y2 orbital order, if the bulk (R,A)MO corresponds to a wide bandwidth manganite. We argue that these results explain some of the properties of long-period (RMO)m/(AMO)n superlattices, such as (PrMnO3)m/(CaMnO3)n and (LaMnO3)m/(SrMnO3)n . We also remark that the intermediate states in between the actual interface and the bulklike regimes of the heterostructure are dependent on the bandwidth and the screening of the Coulomb interaction. In these regions of the heterostructures, states are found that do not have an analog in experimentally known bulk phase diagrams. These new states of the heterostructures provide a natural interpolation between magnetically ordered states that are stable in the bulk at different electronic densities.

Rising CO2 Levels Will Intensify Phytoplankton Blooms in Eutrophic and Hypertrophic Lakes

PubMed Central

Verspagen, Jolanda M. H.; Van de Waal, Dedmer B.; Finke, Jan F.; Visser, Petra M.; Van Donk, Ellen; Huisman, Jef

2014-01-01

Harmful algal blooms threaten the water quality of many eutrophic and hypertrophic lakes and cause severe ecological and economic damage worldwide. Dense blooms often deplete the dissolved CO2 concentration and raise pH. Yet, quantitative prediction of the feedbacks between phytoplankton growth, CO2 drawdown and the inorganic carbon chemistry of aquatic ecosystems has received surprisingly little attention. Here, we develop a mathematical model to predict dynamic changes in dissolved inorganic carbon (DIC), pH and alkalinity during phytoplankton bloom development. We tested the model in chemostat experiments with the freshwater cyanobacterium Microcystis aeruginosa at different CO2 levels. The experiments showed that dense blooms sequestered large amounts of atmospheric CO2, not only by their own biomass production but also by inducing a high pH and alkalinity that enhanced the capacity for DIC storage in the system. We used the model to explore how phytoplankton blooms of eutrophic waters will respond to rising CO2 levels. The model predicts that (1) dense phytoplankton blooms in low- and moderately alkaline waters can deplete the dissolved CO2 concentration to limiting levels and raise the pH over a relatively wide range of atmospheric CO2 conditions, (2) rising atmospheric CO2 levels will enhance phytoplankton blooms in low- and moderately alkaline waters with high nutrient loads, and (3) above some threshold, rising atmospheric CO2 will alleviate phytoplankton blooms from carbon limitation, resulting in less intense CO2 depletion and a lesser increase in pH. Sensitivity analysis indicated that the model predictions were qualitatively robust. Quantitatively, the predictions were sensitive to variation in lake depth, DIC input and CO2 gas transfer across the air-water interface, but relatively robust to variation in the carbon uptake mechanisms of phytoplankton. In total, these findings warn that rising CO2 levels may result in a marked intensification of phytoplankton blooms in eutrophic and hypertrophic waters. PMID:25119996

Enhancement of heterogeneous alkaline xylanase production in Pichia pastoris GS115

NASA Astrophysics Data System (ADS)

Zheng, Wei

2017-08-01

A series of strategies were applied to improve expression level of the recombinant alkaline xylanase from Bacillus pumilus G1-3 in Pichia pastoris GS115. Codon optimization of xylanase gene xynG1-3 from B. pumilus G1-3 were carried out for its heterogeneous expression in P. pastoris. The activity of xylanase encoded by optimized gene (xynG1-3-opt) was up to 33641 U/mL, which was 37% higher than that by wild-type (xynG1-3) gene. The results will greatly contribute to increasing the production of recombinant proteins in P. pastoris and improving the industrial production of the alkaline xylanase.

Evaluating the role of ion composition on the toxicity of copper to Ceriodaphnia dubia in very hard waters.

PubMed

Gensemer, Robert W; Naddy, Rami B; Stubblefield, William A; Hockett, J Russell; Santore, Robert; Paquin, Paul

2002-09-01

The mitigating effect of increasing hardness on metal toxicity is reflected in water quality criteria in the United States over the range of 25-400 mgl(-1) (as CaCO(3)). However, waters in the arid west of the US frequently exceed 400 mgl(-1) hardness, and the applicability of hardness-toxicity relationships in these waters is unknown. Acute toxicity tests with Ceriodaphnia dubia were conducted at hardness levels ranging from approximately 300 to 1,200 mgl(-1) using reconstituted waters that mimic two natural waters with elevated hardness: (1) alkaline desert southwest streams (Las Vegas Wash, NV), and (2) low alkalinity waters from a CaSO(4)-treated mining effluent in Colorado. The moderately-alkaline EPA synthetic hard water was also included for comparison. Copper toxicity did not consistently vary as a function of hardness, but likely as a function of other water quality characteristics (e.g., alkalinity or other correlated factors). The hardness equations used in regulatory criteria, therefore, may not provide an accurate level of protection against copper toxicity in all types of very hard waters. However, the mechanistic Biotic ligand model generally predicted copper toxicity within +/-2X of observed EC(50) values, and thus may be more useful than hardness for modifying water quality criteria.

Cervicovaginal cytokines, sialidase activity and bacterial load in reproductive-aged women with intermediate vaginal flora.

PubMed

Santos-Greatti, Mariana Morena de Vieira; da Silva, Márcia Guimarães; Ferreira, Carolina Sanitá Tafner; Marconi, Camila

2016-11-01

Studies have shown that not only bacterial vaginosis, but also intermediate vaginal flora has deleterious effects for women's reproductive health. However, literature still lacks information about microbiological and immunological aspects of intermediate flora. To characterize intermediate flora regarding levels of Interleukin (IL)-1beta, IL-6, IL-8, tumor necrosis factor-alpha, interleukin 1 receptor antagonist (IL-1ra), IL-10, sialidase; loads of Gardnerella vaginalis, total bacteria and to verify whether it is closer related to normal flora or bacterial vaginosis. This cross-sectional study enrolled 526 non-pregnant reproductive-aged women distributed in 3 groups according to pattern of vaginal flora using Nugent's system in normal, intermediate and bacterial vaginosis. Cervicovaginal levels of cytokines, sialidases, loads of G. vaginalis and total bacteria were assessed by ELISA, conversion of MUAN and quantitative real-time PCR, respectively. A principal component analysis(PCA) using all measured parameters was performed to compare the three different types of flora. Results showed that intermediate flora is associated with increased cervicovaginal IL-1beta in relation to normal flora(P<0.0001). When compared to bacterial vaginosis, intermediate flora has higher IL-8 and IL-10 levels(P<0.01). Sialidases were in significantly lower levels in normal and intermediate flora than bacterial vaginosis(P<0.0001). Loads of G. vaginalis and total bacterial differed among all groups(P<0.0001), being highest in bacterial vaginosis. PCA showed that normal and intermediate flora were closely scattered, while bacterial vaginosis were grouped separately. Although intermediate flora shows some differences in cytokines, sialidases and bacterial loads in relation to normal flora and bacterial vaginosis, when taken together, general microbiological and immunological pattern pattern of intermediate flora resembles the normal flora. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Mobility of as, Cu, Cr, and Zn from tailings covered with sealing materials using alkaline industrial residues: a comparison between two leaching methods.

PubMed

Jia, Yu; Maurice, Christian; Öhlander, Björn

2016-01-01

Different alkaline residue materials (fly ash, green liquor dregs, and lime mud) generated from the pulp and paper industry as sealing materials were evaluated to cover aged mine waste tailings (<1% sulfur content, primarily pyrite). The mobility of four selected trace elements (Cr, Cu, Zn, and As) was compared based on batch and column leaching studies to assess the effectiveness of these alkaline materials as sealing agents. Based on the leaching results, Cr, Cu, and Zn were immobilized by the alkaline amendments. In the amended tailings in the batch system only As dramatically exceeded the limit values at L/S 10 L/kg. The leaching results showed similar patterns to the batch results, though leached Cr, Cu, and Zn showed higher levels in the column tests than in the batch tests. However, when the columns were compared with the batches, the trend for Cu was opposite for the unamended tailings. By contrast, both batch and column results showed that the amendment caused mobilization of As compared with the unamended tailings in the ash-amended tailings. The amount of As released was greatest in the ash column and decreased from the dregs to the lime columns. The leaching of As at high levels can be a potential problem whenever alkaline materials (especially for fly ash) are used as sealing materials over tailings. The column test was considered by the authors to be a more informative method in remediation of the aged tailings with low sulfur content, since it mimics better actual situation in a field.

Effects of parsley (Petroselinum crispum) extract versus glibornuride on the liver of streptozotocin-induced diabetic rats.

PubMed

Ozsoy-Sacan, Ozlem; Yanardag, Refiye; Orak, Haci; Ozgey, Yasemin; Yarat, Aysen; Tunali, Tugba

2006-03-08

Parsley (Petroselinum crispum) is one of the medicinal herbs used by diabetics in Turkey. The aim of this study is to investigate the effects of parsley (2g/kg) and glibornuride (5mg/kg) on the liver tissue of streptozotocin-induced diabetic rats. Swiss albino rats were divided into six groups: control; control+parsley; control+glibornuride; diabetic; diabetic+parsley; diabetic+glibornuride. Diabetes was induced by intraperitoneal injection of 65 mg/kg streptozotocin (STZ). Parsley extract and glibornuride were given daily to both diabetic and control rats separately, until the end of the experiment, at day 42. The drugs were administered to one diabetic and one control group from days 14 to 42. On day 42, liver tissues were taken from each rat. In STZ-diabetic group, blood glucose levels, serum alkaline phosphatase activity, uric acid, sialic acid, sodium and potassium levels, liver lipid peroxidation (LPO), and non-enzymatic glycosylation (NEG) levels increased, while liver glutathione (GSH) levels and body weight decreased. In the diabetic group given parsley, blood glucose, serum alkaline phosphatase activity, sialic acid, uric acid, potassium and sodium levels, and liver LPO and NEG levels decreased, but GSH levels increased. The diabetic group, given glibornuride, blood glucose, serum alkaline phosphatase activity, serum sialic acid, uric acid, potassium, and liver NEG levels decreased, but liver LPO, GSH, serum sodium levels, and body weight increased. It was concluded that probably, due to its antioxidant property, parsley extract has a protective effect comparable to glibornuride against hepatotoxicity caused by diabetes.

Distribution and abundance of schistosomiasis and fascioliasis host snails along the Mara River in Kenya and Tanzania

PubMed Central

Dida, Gabriel O.; Gelder, Frank B.; Anyona, Douglas N.; Matano, Ally-Said; Abuom, Paul O.; Adoka, Samson O.; Ouma, Collins; Kanangire, Canisius K.; Owuor, Phillip O.; Ofulla, Ayub V. O.

2014-01-01

We purposively selected 39 sampling sites along the Mara River and its two perennial tributaries of Amala and Nyangores and sampled snails. In addition, water physicochemical parameters (temperature, turbidity, dissolved oxygen, conductivity, alkalinity, salinity and pH) were taken to establish their influence on the snail abundance and habitat preference. Out of the 39 sites sampled, 10 (25.6%) had snails. The snail species encountered included Biomphalaria pfeifferi Krauss – the intermediate host of Schistosoma mansoni Sambon, Bulinus africanus – the intermediate host of Schistosoma haematobium, and Lymnaea natalensis Krauss – the intermediate host of both Fasciola gigantica and F. hepatica Cobbold. Ceratophallus spp., a non-vector snail was also encountered. Most (61.0%) of the snails were encountered in streamside pools. Schistosomiasis-transmitting host snails, B. pfeifferi and B. africanus, were fewer than fascioliasis-transmitting Lymnaea species. All the four different snail species were found to be attached to different aquatic weeds, with B. pfeifferi accounting for over half (61.1%) of the snails attached to the sedge, followed by B. africanus and Lymnaea spp., accounting for 22.2 and 16.7%, respectively. Ceratophallus spp. were non-existent in sedge. The results from this preliminary study show that snails intermediate hosts of schistosomiasis and fascioliasis exists in different habitats, in few areas along the Mara River, though their densities are still low to have any noticeable impacts on disease transmission in case they are infected. The mere presence of the vector snails in these focal regions calls for their immediate control and institution of proper regulations, management, and education among the locals that can help curtail the spread of the snails and also schistosomiasis and fascioliasis within the Mara River basin. PMID:25405008

Evaluation of secondary hyperparathyroidism in patients undergoing hemodialysis.

PubMed

Rahimian, Mohammad; Sami, Ramin; Behzad, Fariba

2008-01-01

Renal osteodystrophy is a complication of chronic kidney disease (CKD) that present in low and high turnover patterns. This disorder has a key role in the disability of CKD patients in whom early diagnosis and treatment can result in better outcome. We studied hyperparathyroidism prevalence and its relationship with renal osteodystrophy in our advanced CKD population. We included 80 patients (of whom 44 (55%) were diabetic) during 6 months period. The patients answered a questionnaire about symptoms related to bone disease and blood levels of parathormone (PTH), calcium, phosphorus, and alkaline phosphatase were obtained, in addition to hand and skull radiographs in all the study patients. Prevalence of clinically evident hyperparathyroidism in our patients was 45%. Hyperparathyroidism had significant relationship with alkaline phosphatase and radiological findings, but did not have a significant relationship with dialysis duration, age, sex, familial history, diabetes mellitus, or hypertension. We conclude that secondary hyperparathyroidism is prevalent in our dialysis population and has high correlation with serum alkaline phosphatase levels and radiological changes.

Composition of island arcs and continental growth.

NASA Technical Reports Server (NTRS)

Jakes, P.; White, A. J. R.

1971-01-01

Island arc volcanism has contributed and is still contributing to continental growth, but the composition of island arcs differs from that of the upper continental crust in its lower abundance of Si, K, Rb, Ba, Sr and light rare earth elements. In their advanced stage of evolution, island arcs contain more than 80% of tholeiitic and 15% of ?island arc' calc-alkaline rocks with varied SiO2 contents. The larger proportion of tholeiitic rocks is in the lower crustal levels. The high stratigraphical levels of the island arcs are composed of tholeiitic plus calc-alkaline and/or high potash (shoshonitic) associations with higher abundances of K, Rb, Sr, and Ba. Stratification of the island arc crust is accentuated by another type of calc-alkaline volcanism (Andean type) originating at a late stage of arc evolution, probably by partial melting at the base of the crust. This causes enrichment of the upper crust in K, Rb, Ba and REE and accounts for upper crustal abundances of these elements as well as of SiO2.

Isotope geochemistry of recent magmatism in the Aegean arc: Sr, Nd, Hf, and O isotopic ratios in the lavas of Milos and Santorini-geodynamic implications

USGS Publications Warehouse

Briqueu, L.; Javoy, M.; Lancelot, J.R.; Tatsumoto, M.

1986-01-01

In this comparative study of variations in the isotopic compositions (Sr, Nd, O and Hf) of the calc-alkaline magmas of the largest two volcanoes, Milos and Santorini, of the Aegean arc (eastern Mediterranean) we demonstrate the complexity of the processes governing the evolution of the magmas on the scale both of the arc and of each volcano. On Santorini, the crustal contamination processes have been limited, effecting the magma gradually during its differentiation. The most differentiated lavas (rhyodacite and pumice) are also the most contaminated. On Milos, by contrast, these processes are very extensive. They are expressed in the 143Nd/144Nd vs. 87Sr/86Sr diagram as a continuous mixing curve between a mantle and a crustal end member pole defined by schists and metavolcanic rocks outcropping on these volcanoes. In contrast with Santorini, the least differentiated lavas on Milos are the most contaminated. These isotopic singularities can be correlated with the geodynamic evolution of the Aegean subduction zone, consisting of alternating tectonic phases of distension and compression. The genesis of rhyolitic magmas can be linked to the two phases of distension, and the contamination of the calc-alkaline mantle-derived magmas with the intermediate compressive phase. The isotopic characteristics of uncontaminated calc-alkaline primitive magmas of Milos and Santorini are directly comparable to those of magmas generated in subduction zones for which a contribution of subducted sediments to partial melts from the mantle is suggested, such as in the Aleutian, Sunda, and lesser Antilles island arcs. However, in spite of the importance of the sediment pile in the eastern Mediterranen oceanic crust (6-10 km), the contribution of the subducted terrigenous materials remains of limited amplitude. ?? 1986.

Epigallocatechin gallate incorporation into lignin enhances the alkaline delignification and enzymatic saccharification of cell walls

PubMed Central

2012-01-01

Background Lignin is an integral component of the plant cell wall matrix but impedes the conversion of biomass into biofuels. The plasticity of lignin biosynthesis should permit the inclusion of new compatible phenolic monomers such as flavonoids into cell wall lignins that are consequently less recalcitrant to biomass processing. In the present study, epigallocatechin gallate (EGCG) was evaluated as a potential lignin bioengineering target for rendering biomass more amenable to processing for biofuel production. Results In vitro peroxidase-catalyzed polymerization experiments revealed that both gallate and pyrogallyl (B-ring) moieties in EGCG underwent radical cross-coupling with monolignols mainly by β–O–4-type cross-coupling, producing benzodioxane units following rearomatization reactions. Biomimetic lignification of maize cell walls with a 3:1 molar ratio of monolignols and EGCG permitted extensive alkaline delignification of cell walls (72 to 92%) that far exceeded that for lignified controls (44 to 62%). Alkali-insoluble residues from EGCG-lignified walls yielded up to 34% more glucose and total sugars following enzymatic saccharification than lignified controls. Conclusions It was found that EGCG readily copolymerized with monolignols to become integrally cross-coupled into cell wall lignins, where it greatly enhanced alkaline delignification and subsequent enzymatic saccharification. Improved delignification may be attributed to internal trapping of quinone-methide intermediates to prevent benzyl ether cross-linking of lignin to structural polysaccharides during lignification, and to the cleavage of ester intra-unit linkages within EGCG during pretreatment. Overall, our results suggest that apoplastic deposition of EGCG for incorporation into lignin would be a promising plant genetic engineering target for improving the delignification and saccharification of biomass crops. PMID:22889353

Chabazite and dolomite formation in a dolocrete profile: An example of a complex alkaline paragenesis in Lanzarote, Canary Islands

NASA Astrophysics Data System (ADS)

Alonso-Zarza, Ana M.; Bustamante, Leticia; Huerta, Pedro; Rodríguez-Berriguete, Álvaro; Huertas, María José

2016-05-01

This paper studies the weathering and soil formation processes operating on detrital sediments containing alkaline volcanic rock fragments of the Mirador del Río dolocrete profile. The profile consists of a lower horizon of removilised weathered basalts, an intermediate red sandy mudstones horizon with irregular carbonate layers and a topmost horizon of amalgamated carbonate layers with root traces. Formation occurred in arid to semiarid climates, giving place to a complex mineralogical association, including Mg-carbonates and chabazite, rarely described in cal/dolocretes profiles. Initial vadose weathering processes occurred in the basalts and in directly overlying detrital sediments, producing (Stage 1) red-smectites and dolomicrite. Dominant phreatic (Stage 2) conditions allowed precipitation of coarse-zoned dolomite and chabazite filling porosities. In Stages 3 and 4, mostly pedogenic, biogenic processes played an important role in dolomite and calcite accumulation in the profile. Overall evolution of the profile and its mineralogical association involved initial processes dominated by alteration of host rock, to provide silica and Mg-rich alkaline waters, suitable for chabazite and dolomite formation, without a previous carbonate phase. Dolomite formed both abiogenically and biogenically, but without a previous carbonate precursor and in the absence of evaporites. Dominance of calcite towards the profile top is the result of Mg/Ca decrease in the interstitial meteoric waters due to decreased supply of Mg from weathering, and increased supply of Ca in aeolian dust. Meteoric origin of the water is confirmed by C and O isotope values, which also indicate lack of deep sourced CO2. The dolocrete studied and its complex mineral association reveal the complex interactions that occur at surface during weathering and pedogenesis of basalt-sourced rocks.

Hypoxia and alkalinization inhibit endothelium-derived nitric oxide but not endothelium-derived hyperpolarizing factor responses in porcine coronary artery.

PubMed

Shimizu, S; Paul, R J

1999-10-01

We investigated the mechanisms by which hypoxia and alkalinization inhibit the endothelium-dependent relaxation to Substance P (SP) in porcine coronary artery. In a KCl contracture, the major component of the SP response is endothelium-derived nitric oxide (EDNO), whereas with receptor-mediated 9,11-dideoxy-llalpha, 9alpha-epoxymethanoprostaglandin F(2alpha) (U46619) stimulation, the SP response is dependent on both EDNO and endothelium-derived hyperpolarization factor. Intracellular alkalinization by NH(4)Cl reduced the peak of SP responses when arteries were contracted with KCl, whereas with U46619 stimulation, the peak was little effected but the duration was shortened. In endothelial cell-denuded arteries, alkalinization with NH(4)Cl shifted the sodium nitroprusside concentration-relaxation relations rightward. The effects of NH(4)Cl in SP- and sodium nitroprusside-induced relaxations were attenuated by decreasing extracellular pH (pH(o)) from 7.4 to 7.2, which normalized intracellular pH (pH(i)) to control levels. In contrast, in U46619 contractures, the SP response in the presence of a NO synthase inhibitor was unaffected by NH(4)Cl. Moreover, hypoxia blunted but did not abolish the responses to SP for U46619 contractures; addition of KCl, however, abolished the SP response under hypoxia. Endothelial [Ca(2+)](i) was measured with fura-2 differentially loaded only into endothelial cells on intact arteries. Despite the attenuation of the SP response in KCl contractures by NH(4)Cl or hypoxia, endothelial [Ca(2+)](i) responses were unchanged. Our results suggest that hypoxia and alkalinization inhibit EDNO but not endothelium-derived hyperpolarization factor relaxations through a mechanism(s) not involving endothelial cell [Ca(2+)](i). Inhibition of EDNO relaxation by alkalinization with NH(4)Cl is likely to occur at the level of activation of guanylate cyclase and/or at a step downstream in smooth muscle.

Beneficial role of spermidine in chlorophyll metabolism and D1 protein content in tomato seedlings under salinity-alkalinity stress.

PubMed

Hu, Lipan; Xiang, Lixia; Li, Shuting; Zou, Zhirong; Hu, Xiao-Hui

2016-04-01

Polyamines are important in protecting plants against various environmental stresses, including protection against photodamage to the photosynthetic apparatus. The molecular mechanism of this latter effect is not completely understood. Here, we have investigated the effects of salinity-alkalinity stress and spermidine (Spd) on tomato seedlings at both physiological and transcriptional levels. Salinity-alkalinity stress decreased leaf area, net photosynthetic rate, maximum net photosynthetic rate, light saturation point, apparent quantum efficiency, total chlorophyll, chlorophyll a and chlorophyll a:chlorophyll b relative to the control. The amount of D1 protein, an important component of photosystem II, was reduced compared with the control, as was the expression of psbA, which codes for D1. Expression of the chlorophyll biosynthesis gene porphobilinogen deaminase (PBGD) was reduced following salinity-alkalinity stress, whereas the expression of Chlase, which codes for chlorophyllase, was increased. These negative physiological effects of salinity-alkalinity stress were alleviated by exogenous Spd. Expression of PBGD and psbA were enhanced, whereas the expression of Chlase was reduced, when exogenous Spd was included in the stress treatment compared with when it was not. The protective effect of Spd on chlorophyll and D1 protein content during stress may maintain the photosynthetic apparatus, permitting continued photosynthesis and growth of tomato seedlings (Solanum lycopersicum cv. Jinpengchaoguan) under salinity-alkalinity stress. © 2015 Scandinavian Plant Physiology Society.

Adsorption of alkali and alkaline earth metal atoms and dimers on monolayer germanium carbide

NASA Astrophysics Data System (ADS)

Gökçe, Aytaç Gürhan; Ersan, Fatih

2017-01-01

First-principles plane wave calculations have been performed to study the adsorption of alkali and alkaline earth metals on monolayer germanium carbide (GeC). We found that the favourable adsorption sites on GeC sheet for single alkali and alkaline earth adatoms are generally different from graphene or germanene. Among them, Mg, Na and their dimers have weakly bounded to GeC due to their closed valence electron shells, so they may have high mobility on GeC. Two different levels of adatom coverage (? and ?) have been investigated and we concluded that different electronic structures and magnetic moments for both coverages owing to alkali and alkaline earth atoms have long range electrostatic interactions. Lithium atom prefers to adsorbed on hollow site similar to other group-IV monolayers and the adsorption results in metallisation of GeC instead of semiconducting behaviour. Na and K adsorption can induce 1 ? total magnetic moment on GeC structures and they have shown semiconductor property which may have potential use in spintronic devices. We also showed that alkali or alkaline earth metal atoms can form dimer on GeC sheet. Calculated adsorption energies suggest that clustering of alkali and alkaline earth atoms is energetically favourable. All dimer adsorbed GeC systems have nonmagnetic semiconductor property with varying band gaps from 0.391 to 1.311 eV which are very suitable values for various device applications.

Bile duct obstruction

MedlinePlus

... Tumors that have spread to the biliary system Liver and bile duct worms (flukes) The risk factors include: History of ... Increased bilirubin level Increased alkaline phosphatase level Increased liver enzymes The ... CT scan Endoscopic retrograde cholangiopancreatography ( ...

Effects of water level on three wetlands soil seed banks on the Tibetan Plateau.

PubMed

Ma, Miaojun; Ma, Zhen; Du, Guozhen

2014-01-01

Although the effect of water level on germination in soil seed banks has been documented in many ecosystems, the mechanism is not fully understood, and to date no empirical studies on this subject exist. Further, no work has been done on the effect of water level on seed banks of drying and saline-alkaline wetlands in alpine areas on the Tibetan Plateau. We examined the effects of water level (0 cm, 5 cm and 10 cm) on seed germination and seedling establishment from soil seed banks at 0-5 cm and 5-10 cm depths in typical, drying, and saline-alkaline wetlands. We also explore the potential role of soil seed bank in restoration of drying and saline-alkaline wetlands. Species richness decreased with increase in water level, but there almost no change in seed density. A huge difference exists in species composition of the seed bank among different water levels in all three wetlands, especially between 0 cm and 5 cm and 0 cm and 10 cm. Similarity of species composition between seed bank and plant community was higher in 0 cm water level in drying wetland than in the other two wetlands. The similarity was much higher in 0 cm water level than in 5 cm and 10 cm water levels in all three wetlands. Species composition of the alpine wetland plant community changed significantly after drying and salinization, however, species composition of the seed bank was unchanged regardless of the environment change. Water level greatly affects seed bank recruitment and plant community establishment. Further, different water levels in restored habitats are likely to determine its species composition of the plant community. The seed bank is important in restoration of degraded wetlands. Successful restoration of drying and salinization wetlands could depend on the seed bank.

Response to alkaline stress by root canal bacteria in biofilms.

PubMed

Chávez de Paz, L E; Bergenholtz, G; Dahlén, G; Svensäter, G

2007-05-01

To determine whether bacteria isolated from infected root canals survive alkaline shifts better in biofilms than in planktonic cultures. Clinical isolates of Enterococcus faecalis, Lactobacillus paracasei, Olsenella uli, Streptococcus anginosus, S. gordonii, S. oralis and Fusobacterium nucleatum in biofilm and planktonic cultures were stressed at pH 10.5 for 4 h, and cell viability determined using the fluorescent staining LIVE/DEAD BacLight bacterial viability kit. In addition, proteins released into extracellular culture fluids were identified by Western blotting. Enterococcus faecalis, L. paracasei, O. uli and S. gordonii survived in high numbers in both planktonic cultures and in biofilms after alkaline challenge. S. anginosus, S. oralis and F. nucleatum showed increased viability in biofilms compared with planktonic cultures. Alkaline exposure caused all planktonic cultures to aggregate into clusters and resulted in a greater extrusion of cellular proteins compared with cells in biofilms. Increased levels of DnaK, HPr and fructose-1,6-bisphosphate aldolase were observed in culture fluids, especially amongst streptococci. In general, bacteria isolated from infected roots canals resisted alkaline stress better in biofilms than in planktonic cultures, however, planktonic cells appeared to use aggregation and the extracellular transport of specific proteins as survival mechanisms.

Elementary Environmental Learning Packet Grades 4-6, Second Revised Edition. [Intermediate CEL Blocks. Teacher's Guide].

ERIC Educational Resources Information Center

Brevard County School Board, Cocoa, FL.

This environmental education program consists of two levels: primary and intermediate. The material in this publication encompasses the intermediate level. The learning materials are activity-based and incorporate process and subject area skills with knowledge and concern for the environment. The program is also interdisciplinary including…

Probable levetiracetam-related serum alkaline phosphatase elevation

PubMed Central

2012-01-01

Background Levetiracetam (LEV) is an antiepileptic drug with a favorable tolerability and safety profile with little or no effect on liver function. Case presentation Here, we reported an epileptic pediatric patient who developed a significant elevation in serum alkaline phosphatase level (ALP) during LEV monotherapy. Moreover, the serum ALP level was surprisingly decreased to normal after LEV discontinuation. The Naranjo Adverse Drug Reaction Probability Scale score was 6, indicating firstly LEV was a probable cause for the increased serum ALP. Conclusions Cautious usage and concerns of the LEV-associated potential ALP elevation should be considered when levetiracetam is prescribed to epilepsy patients, especially pediatric patients. PMID:22994584

Microbial destruction by low concentrations of hypochlorite and iodophor germicides in alkaline and acidified water.

PubMed

Hays, H; Elliker, P R; Sandine, W E

1967-05-01

Hypochlorite and iodophor germicides were evaluated for their ability to destroy a variety of organisms at levels approximating those used for final sanitizing rinse for dairy and food equipment and beverage bottles (3 to 50 ppm). Test organisms included Escherichia coli, Streptococcus lactis, Lactobacillus plantarum, Pediococcus cerevisiae, and Saccharomyces cerevisiae. The hypochlorites and iodophors demonstrated approximate rates of destruction at equivalent concentrations for the bacterial species tested, except where the hypochlorite contained excess alkalinity. The hypochlorite responded more readily to a downward shift to a pH of 5.0 than did the iodophor. Excess alkalinity of the hypochlorite significantly affected its bactericidal activity. The iodophor exhibited a consistently greater rate of destruction of yeast cells than the hypochlorite. Successive treatment with low levels of iodophor (6 ppm) followed by a hypochlorite (12 to 25 ppm) resulted in a high level of destruction of all test organisms. Possibilities for employing these measures in a sanitizing rinse of bottles for maximal destruction of organisms were discussed. Among the test organisms, S. lactis showed a comparatively high resistance and was a useful organism for comparing the halogen preparations.

Enhanced Catalytic Activities of NiPt Truncated Octahedral Nanoparticles toward Ethylene Glycol Oxidation and Oxygen Reduction in Alkaline Electrolyte.

PubMed

Xia, Tianyu; Liu, Jialong; Wang, Shouguo; Wang, Chao; Sun, Young; Gu, Lin; Wang, Rongming

2016-05-04

The high cost and poor durability of Pt nanoparticles (NPs) are great limits for the proton exchange membrane fuel cells (PEMFCs) from being scaled-up for commercial applications. Pt-based bimetallic NPs together with a uniform distribution can effectively reduce the usage of expensive Pt while increasing poison resistance of intermediates. In this work, a simple one-pot method was used to successfully synthesize ultrafine (about 7.5 nm) uniform NiPt truncated octahedral nanoparticles (TONPs) in dimethylformamid (DMF) without any seeds or templates. The as-prepared NiPt TONPs with Pt-rich surfaces exhibit greatly improved catalytic activities together with good tolerance and better stability for ethylene glycol oxidation reaction (EGOR) and oxygen reduction reaction (ORR) in comparison with NiPt NPs and commercial Pt/C catalysts in alkaline electrolyte. For example, the value of mass and specific activities for EGOR are 23.2 and 17.6 times higher comparing with those of commercial Pt/C, respectively. Our results demonstrate that the dramatic enhancement is mainly attributed to Pt-rich surface, larger specific surface area, together with coupling between Ni and Pt atoms. This developed method provides a promising pathway for simple preparation of highly efficient electrocatalysts for PEMFCs in the near future.

A novel approach for arsenic adsorbents regeneration using MgO.

PubMed

Tresintsi, Sofia; Simeonidis, Konstantinos; Katsikini, Maria; Paloura, Eleni C; Bantsis, Georgios; Mitrakas, Manassis

2014-01-30

An integrated procedure for the regeneration of iron oxy-hydroxide arsenic adsorbents by granulated MgO is proposed in this study. A continuous recirculation configuration, with a NaOH solution flowing sequentially through the saturated adsorbent (leaching step) and the MgO (adsorption step) column beds, was optimized by utilizing the high arsenic adsorption efficiency of MgO at strong alkaline environments. Experimental results indicated that the total amount of leached arsenic was captured by MgO whereas the regenerated iron oxy-hydroxide recovered around 80% of its removal capacity upon reuse. The improved adsorption capacity of MgO for As(V), which is maximized at pH 10, is explained by the intermediate hydration to Mg(OH)2 and the following As(V) oxy-anions adsorption on its surface through the formation of monodentate inner sphere complexes, as it is deduced from the AsK-edge X-ray absorption fine structure (EXAFS) analysis. In addition to the economical-benefits, corresponding tests proved that the solid wastes of this process, namely spent MgO/Mg(OH)2, can be environmentally safely disposed as stable additives in cement products, while the alkaline solution is completely detoxified and can be recycled to the regeneration task. Copyright © 2013 Elsevier B.V. All rights reserved.

Pd supported on carbon containing nickel, nitrogen and sulfur for ethanol electrooxidation.

PubMed

Yang, Zi-Rui; Wang, Shang-Qing; Wang, Jing; Zhou, Ai-Ju; Xu, Chang-Wei

2017-11-13

Carbon material containing nickel, nitrogen and sulfur (Ni-NSC) has been synthesized using metal-organic frameworks (MOFs) as precursor by annealing treatment with a size from 200 to 300 nm. Pd nanoparticles supported on the Ni-NSC (Pd/Ni-NSC) are used as electrocatalysts for ethanol oxidation in alkaline media. Due to the synergistic effect between Pd and Ni, S, N, free OH radicals can form on the surface of Ni, N and S atoms at lower potentials, which react with CH 3 CO intermediate species on the Pd surface to produce CH 3 COO - and release the active sites. On the other hand, the stronger binding force between Pd and co-doped N and S is responsible for enhancing dispersion and preventing agglomeration of the Pd nanoparticles. The Pd(20 wt%)/Ni-NSC shows better electrochemical performance of ethanol oxidation than the traditional commercial Pd(20 wt%)/C catalyst. Onset potential on the Pd(20 wt%)/Ni-NSC electrode is 36 mV more negative compared with that on the commercial Pd(20 wt%)/C electrode. The Pd(20 wt%)/Ni-NSC in this paper demonstrates to have excellent electrocatalytic properties and is considered as a promising catalyst in alkaline direct ethanol fuel cells.

Reversible Hydrolysis Reaction with the Spore Photoproduct under Alkaline Conditions.

PubMed

Adhikari, Surya; Lin, Gengjie; Li, Lei

2016-09-16

DNA lesions may reduce the electron density at the nucleobases, making them prone to further modifications upon the alkaline treatment. The dominant DNA photolesion found in UV-irradiated bacterial endospores is a thymine dimer, 5-thyminyl-5,6-dihydrothymine, i.e., the spore photoproduct (SP). Here we report a stepwise addition/elimination reaction in the SP hydrolysis product under strong basic conditions where a ureido group is added to the carboxyl moiety to form a cyclic amide, regenerating SP after eliminating a hydroxide ion. Direct amidation of carboxylic acids by reaction with amines in the presence of a catalyst is well documented; however, it is very rare for an amidation reaction to occur without activation. This uncatalyzed SP reverse reaction in aqueous solution is even more surprising because the carboxyl moiety is not a good electrophile due to the negative charge it carries. Examination of the base-catalyzed hydrolyses of two other saturated pyrimidine lesions, 5,6-dihydro-2'-deoxyuridine and pyrimidine (6-4) pyrimidone photoproduct, reveals that neither reaction is reversible even though all three hydrolysis reactions may share the same gem-diol intermediate. Therefore, the SP structure where the two thymine residues maintain a stacked conformation likely provides the needed framework enabling this highly unusual carboxyl addition/elimination reaction.

Rethinking CCD's Significance in Estimating Late Neogene Whole Ocean Carbonate Budget

NASA Astrophysics Data System (ADS)

Si, W.; Rosenthal, Y.

2017-12-01

The global averaged calcite compensation depth (CCD) record is conventionally used to reconstruct two correlatable parameters of the carbonate system - the alkalinity budget of the ocean and/or the saturation state of the ocean. Accordingly, the available CCD reconstructions have been interpreted to suggest either relative stable (Pearson and Palmer, 2000) or increased alkalinity of the ocean over the past 15 Ma (Tyrrell and Zeebe, 2004; Pälike et al., 2012). However, CCD alone is insufficient to constrain the carbonate system because the weathering flux of alkalinity into the ocean is not only balanced by CaCO3 dissolution on the seafloor but also by the biologic production in the euphotic zone and, the CCD records cannot be readily interpreted as changes in either process. Here, we present evidence of the co-evolution of surface CaCO3 production and deepsea dissolution through the late Neogene. By examining separately the mass accumulation rates (MAR) of coccoliths, planktonic foraminifera, and quantifying dissolution (using a proxy revised from Broecker et al., 1999) in seventeen deepsea cores from multiple depth-transects, we find that 1) MAR of dissolution-resistant coccoliths was substantially higher in the mid Miocene and declining on a global scale towards the present; 2) unlike coccoliths, MAR of planktonic foraminifera, shows no apparent secular trend through that time; 3) the revised dissolution index, shows significantly improved preservation of planktonic foraminiferal shells over that time, particularly at intermediate water depth and exhibits close association between changes in preservation with key climatic events. Our new records have two immediate implications. First, the substantially weakened pelagic biogenic carbonate production from mid Miocene to present alone could account for the improved preservation of deepsea carbonates without calling for a scenario of increased weathering input. Second, with the constrain of global averaged CCD records, the net accumulation of pelagic carbonate has declined over the course of late Neogene. Hence, the weathering alkalinity input should have decreased since 15 Ma, as oppose to the weathering hypothesis (Raymo et al., 1988).

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bertheussen, Erlend; Verdaguer-Casadevall, Arnau; Ravasio, Davide

Oxide-derived copper (OD-Cu) electrodes exhibit unprecedented CO reduction performance towards liquid fuels, producing ethanol and acetate with >50 % Faradaic efficiency at -0.3 V (vs. RHE). By using static headspace-gas chromatography for liquid phase analysis, we identify acetaldehyde as a minor product and key intermediate in the electroreduction of CO to ethanol on OD-Cu electrodes. Acetaldehyde is produced with a Faradaic efficiency of ≈5 % at -0.33 V (vs. RHE). We show that acetaldehyde forms at low steady-state concentrations, and that free acetaldehyde is difficult to detect in alkaline solutions using NMR spectroscopy, requiring alternative methods for detection and quantification.more » Our results indicate an important step towards understanding the CO reduction mechanism on OD-Cu electrodes.« less

Geochemistry of the 1989-1990 eruption of redoubt volcano: Part I. Whole-rock major- and trace-element chemistry

USGS Publications Warehouse

Nye, C.J.; Swanson, S.E.; Avery, V.F.; Miller, T.P.

1994-01-01

The 1989-1990 eruption of Redoubt Volcano produced medium-K calc-alkaline andesite and dacite of limited compositional range (58.2-63.4% SiO2) and entrained quenched andesitic inclusions (55% SiO2) which bear chemical similarities to the rest of the ejecta. The earliest (December 15) magmas are pumiceous, often compositionally banded, and the majority is relatively mafic ( 60 wt.%). They have Mg, Cr, Ni, Sc, and V contents higher than the andesites, but lower than Redoubt basalts and basaltic andesites. Thus, they may be crystallization products of andesites, but do not represent the cumulate residue of basalt fractionation. The xenoliths were probably derived from a shallow or intermediate crustal chamber. ?? 1994.

Study of the electrochemical oxidation and reduction of C.I. Reactive Orange 4 in sodium sulphate alkaline solutions.

PubMed

del Río, A I; Molina, J; Bonastre, J; Cases, F

2009-12-15

Synthetic solutions of hydrolysed C.I. Reactive Orange 4, a monoazo textile dye commercially named Procion Orange MX-2R (PMX2R) and colour index number C.I. 18260, was exposed to electrochemical treatment under galvanostatic conditions and Na2SO4 as electrolyte. The influence of the electrochemical process as well as the applied current density was evaluated. Ti/SnO2-Sb-Pt and stainless steel electrodes were used as anode and cathode, respectively, and the intermediates generated on the cathode during electrochemical reduction were investigated. Aliquots of the solutions treated were analysed by UV-visible and FTIR-ATR spectroscopy confirming the presence of aromatic structures in solution when an electro-reduction was carried out. Electro-oxidation degraded both the azo group and aromatic structures. HPLC measures revealed that all processes followed pseudo-first order kinetics and decolourisation rates showed a considerable dependency on the applied current density. CV experiments and XPS analyses were carried out to study the behaviour of both PMX2R and intermediates and to analyse the state of the cathode after the electrochemical reduction, respectively. It was observed the presence of a main intermediate in solution after an electrochemical reduction whose chemical structure is similar to 2-amino-1,5-naphthalenedisulphonic acid. Moreover, the analysis of the cathode surface after electrochemical reduction reveals the presence of a coating layer with organic nature.

Use of CAS in secondary school: a factor influencing the transition to university-level mathematics?

NASA Astrophysics Data System (ADS)

Varsavsky, Cristina

2012-01-01

Australian secondary school systems offer three levels of senior (year 12) mathematics studies, none of them compulsory: elementary, intermediate and advanced. The intermediate and advanced studies prepare students for further mathematics studies at university level. In the state of Victoria, there are two versions of intermediate mathematics: one where students learn and are examined with a computer algebra system (CAS) and another where students can only use scientific calculators. This study compares the performance of 1240 students as they transitioned to traditional university-level mathematics and according to whether they learned intermediate mathematics with or without the assistance of a CAS. This study concludes that students without CAS show a slight advantage, but the most important factor affecting student performance is the uptake of advanced-level mathematics studies in secondary school.

Levels of Processing in Mild Disabilities.

ERIC Educational Resources Information Center

Al-Hilawani, Yasser A.; And Others

This study examined the effects of the second level (intermediate acoustical processing of rhyming words) and the third level (deep-semantic processing of words in sentences) of the "levels of processing" framework on memory performance of four types of intermediate-grade students (52 "normal" students, 50 students with…

Early containment of high-alkaline solution simulating low-level radioactive waste stream in clay-bearing blended cement

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kruger, A.A.; Olson, R.A.; Tennis, P.D.

1995-04-01

Portland cement blended with fly ash and attapulgite clay was mixed with high-alkaline solution simulating low-level radioactive waste stream at a one-to-one weight ratio. Mixtures were adiabatically and isothermally cured at various temperatures and analyzed for phase composition, total alkalinity, pore solution chemistry, and transport properties as measured by impedance spectroscopy. Total alkalinity is characterized by two main drops. The early one corresponds to a rapid removal of phosphorous, aluminum, sodium, and to a lesser extent potassium solution. The second drop from about 10 h to 3 days is mainly associated with the removal of aluminum, silicon, and sodium. Thereafter,more » the total alkalinity continues descending, but at a lower rate. All pastes display a rapid flow loss that is attributed to an early precipitation of hydrated products. Hemicarbonate appears as early as one hour after mixing and is probably followed by apatite precipitation. However, the former is unstable and decomposes at a rate that is inversely related to the curing temperature. At high temperatures, zeolite appears at about 10 h after mixing. At 30 days, the stabilized crystalline composition Includes zeolite, apatite and other minor amounts of CaCO{sub 3}, quartz, and monosulfate Impedance spectra conform with the chemical and mineralogical data. The normalized conductivity of the pastes shows an early drop, which is followed by a main decrease from about 12 h to three days. At three days, the permeability of the cement-based waste as calculated by Katz-Thompson equation is over three orders of magnitude lower than that of ordinary portland cement paste. However, a further decrease in the calculated permeability is questionable. Chemical stabilization is favorable through incorporation of waste species into apatite and zeolite.« less

Compensatory Cellular Reactions to Nonsteroidal Anti-Inflammatory Drugs on Osteogenic Differentiation in Canine Bone Marrow-Derived Mesenchymal Stem Cells

PubMed Central

OH, Namgil; KIM, Sangho; HOSOYA, Kenji; OKUMURA, Masahiro

2014-01-01

ABSTRACT The suppressive effects of nonsteroidal anti-inflammatory drugs (NSAIDs) on the bone healing process have remained controversial, since no clinical data have clearly shown the relationship between NSAIDs and bone healing. The aim of this study was to assess the compensatory response of canine bone marrow-derived mesenchymal stem cells (BMSCs) to several classes of NSAIDs, including carprofen, meloxicam, indomethacin and robenacoxib, on osteogenic differentiation. Each of the NSAIDs (10 µM) was administered during 20 days of the osteogenic process with human recombinant IL-1β (1 ng/ml) as an inflammatory stimulator. Gene expression of osteoblast differentiation markers (alkaline phosphatase and osteocalcin), receptors of PGE2 (EP2 and EP4) and enzymes for prostaglandin (PG) E2 synthesis (COX-1, COX-2, cPGES and mPGES-1) was measured by using quantitative reverse transcription-polymerase chain reaction. Protein production levels of alkaline phosphatase, osteocalcin and PGE2 were quantified using an alkaline phosphatase activity assay, osteocalcin immunoassay and PGE2 immunoassay, respectively. Histologic analysis was performed using alkaline phosphatase staining, von Kossa staining and alizarin red staining. Alkaline phosphatase and calcium deposition were suppressed by all NSAIDs. However, osteocalcin production showed no significant suppression by NSAIDs. Gene expression levels of PGE2-related receptors and enzymes were upregulated during continuous treatment with NSAIDs, while certain channels for PGE2 synthesis were utilized differently depending on the kind of NSAIDs. These data suggest that canine BMSCs have a compensatory mechanism to restore PGE2 synthesis, which would be an intrinsic regulator to maintain differentiation of osteoblasts under NSAID treatment. PMID:24419976

Increase of protein extraction yield from rapeseed meal through a pretreatment with phytase.

PubMed

Rodrigues, Ivo M; Carvalho, M Graça Vs; Rocha, Jorge Ms

2017-06-01

Rapeseed meal is a good source of high-quality vegetal protein but contains antinutritional compounds that limit its use for human and animal feed. The aim of this study was to develop a methodology to enhance alkaline protein extraction of rapeseed meal and to produce protein-rich products with low levels of phytic acid. Different phytase dosages and operating conditions were used for rapeseed meal pretreatment followed by alkaline extraction at different temperatures, time, pH and solid/liquid ratios (S/L). The highest protein extraction yield attained was 72.1%, for 2 h at 55 °C, with a phytase dosage of 0.8 U g -1 when the alkaline extraction was performed at 75 °C, pH 12.5 and 60 min for an S/L ratio of 10 g 100 mL -1 water. The extraction yields were higher than those previously obtained without enzymatic pretreatment. Phytase pretreatment enhanced alkaline extraction yield of proteins from rapeseed meal. This procedure allowed also the production of rapeseed protein concentrates with very low levels of phytic acid, ∼1 g kg -1 , improving their nutritional properties and commercial value. Moreover, after the pretreatment, the amount of phytic acid in the remaining rapeseed meal decreases about 25%. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Effects of Comic Strips on L2 Learners' Reading Comprehension

ERIC Educational Resources Information Center

Liu, Jun

2004-01-01

This article reports the results of an experiment investigating the role of comic strips on ESL learners' reading comprehension. The students' proficiency levels were estimated, and students were organized into a low intermediate-level proficiency group (low-level students) and a high intermediate-level proficiency group (high-level students).…

Mechanochemical activation and gallium and indiaarsenides surface catalycity

NASA Astrophysics Data System (ADS)

Kirovskaya, I. A.; Mironova, E. V.; Umansky, I. V.; Brueva, O. Yu; Murashova, A. O.; Yureva, A. V.

2018-01-01

The present work has been carried out in terms of determining the possibilities for a clearer identification of the active sites nature, intermediate surface compounds nature, functional groups during adsorption and catalysis, activation of the diamond-like semiconductors surface (in particular, the AIIIBV type) based on mechanochemical studies of the “reaction medium (H2O, iso-C3H7OH) - dispersible semiconductor (GaAs, InAs)” systems. As a result, according to the read kinetic curves of dispersion in water, both acidification and alkalinization of the medium have been established and explained; increased activity of the newly formed surface has been noted; intermediate surface compounds, functional groups appearing on the real surface and under H2O adsorption conditions, adsorption and catalytic decomposition of iso-C3H7OH have been found (with explanation of the origin). The unconcealed role of coordinatively unsaturated atoms as active sites of these processes has been shown; the relative catalytic activity of the semiconductors studied has been evaluated. Practical recommendations on the preferred use of gallium arsenide in semiconductor gas analysis and semiconductor catalysis have been given in literature searches, great care should be taken in constructing both.

GsERF6, an ethylene-responsive factor from Glycine soja, mediates the regulation of plant bicarbonate tolerance in Arabidopsis.

PubMed

Yu, Yang; Liu, Ailin; Duan, Xiangbo; Wang, Sunting; Sun, Xiaoli; Duanmu, Huizi; Zhu, Dan; Chen, Chao; Cao, Lei; Xiao, Jialei; Li, Qiang; Nisa, Zaib Un; Zhu, Yanming; Ding, Xiaodong

2016-09-01

This is an original study focus on ERF gene response to alkaline stress. GsERF6 functions as transcription factor and significantly enhanced plant tolerance to bicarbonate (HCO 3 (-) ) in transgenic Arabidopsis . Alkaline stress is one of the most harmful, but little studied environmental factors, which negatively affects plant growth, development and yield. The cause of alkaline stress is mainly due to the damaging consequence of high concentration of the bicarbonate ion, high-pH, and osmotic shock to plants. The AP2/ERF family genes encode plant-specific transcription factors involved in diverse environmental stresses. However, little is known about their physiological functions, especially in alkaline stress responses. In this study, we functionally characterized a novel ERF subfamily gene, GsERF6 from alkaline-tolerant wild soybean (Glycine soja). In wild soybean, GsERF6 was rapidly induced by NaHCO3 treatment, and its overexpression in Arabidopsis enhanced transgenic plant tolerance to NaHCO3 challenge. Interestingly, GsERF6 transgenic lines also displayed increased tolerance to KHCO3 treatment, but not to high pH stress, implicating that GsERF6 may participate specifically in bicarbonate stress responses. We also found that GsERF6 overexpression up-regulated the transcription levels of bicarbonate-stress-inducible genes such as NADP-ME, H (+)-Ppase and H (+)-ATPase, as well as downstream stress-tolerant genes such as RD29A, COR47 and KINI. GsERF6 overexpression and NaHCO3 stress also altered the expression patterns of plant hormone synthesis and hormone-responsive genes. Conjointly, our results suggested that GsERF6 is a positive regulator of plant alkaline stress by increasing bicarbonate ionic resistance specifically, providing a new insight into the regulation of gene expression under alkaline conditions.

Groundwater quality assessment in the village of Lutfullapur Nawada, Loni, District Ghaziabad, Uttar Pradesh, India.

PubMed

Singh, Vinod K; Bikundia, Devendra Singh; Sarswat, Ankur; Mohan, Dinesh

2012-07-01

The groundwater quality for drinking, domestic and irrigation in the village Lutfullapur Nawada, Loni, district Ghaziabad, U.P., India, has been assessed. Groundwater samples were collected, processed and analyzed for temperature, pH, conductivity, salinity, total alkalinity, carbonate alkalinity, bicarbonate alkalinity, total hardness, calcium hardness, magnesium hardness, total solids, total dissolved solids, total suspended solids, nitrate-nitrogen, chloride, fluoride, sulfate, phosphate, silica, sodium, potassium, calcium, magnesium, total chromium, cadmium, copper, iron, nickel, lead and zinc. A number of groundwater samples showed levels of electrical conductivity (EC), alkalinity, chloride, calcium, sodium, potassium and iron exceeding their permissible limits. Except iron, the other metals (Cr, Cd, Cu, Ni, Pb, and Zn) were analyzed below the permissible limits. The correlation matrices for 28 variables were performed. EC, salinity, TS and TDS had significant positive correlations among themselves and also with NO (3) (-) , Cl(-), alkalinity, Na(+), K(+), and Ca(2+). Fluoride was not significantly correlated with any of the parameters. NO (3) (-) was significantly positively correlated with Cl(-), alkalinity, Na(+), K(+) and Ca(2+). Chloride also correlated significantly with alkalinity, Na(+), K(+) and Ca(2+). Sodium showed a strong and positive correlation with K(+) and Ca(2+). pH was negatively correlated with most of the physicochemical parameters. This groundwater is classified as a normal sulfate and chloride type. Base-exchange indices classified 73% of the groundwater sources as the Na(+)-SO (4) (2-) type. The meteoric genesis indices demonstrated that 67% of groundwater sources belong to a deep meteoric water percolation type. Hydrochemical groundwater evaluations revealed that most of the groundwaters belong to the Na(+)-K(+)-Cl(-)-SO (4) (2-) type followed by Na(+)-K(+)-HCO (3) (-) type. Salinity, chlorinity and SAR indices indicated that majority of groundwater samples can be considered suitable for irrigation purposes.

Potential benefits of pH 8.8 alkaline drinking water as an adjunct in the treatment of reflux disease.

PubMed

Koufman, Jamie A; Johnston, Nikki

2012-07-01

At the cellular level, tissue-bound pepsin is fundamental to the pathophysiologic mechanism of reflux disease, and although the thresholds for laryngeal damage in laryngopharyngeal reflux and for esophageal damage in gastroesophageal reflux disease differ, both forms of damage are due to pepsin, which requires acid for its activation. In addition, human pepsin remains stable at pH 7.4 and may be reactivated by hydrogen ions from any source. Thus, most tap and bottled waters (typically pH 6.7 to 7.4) would not be expected to affect pepsin stability. The purposes of these in vitro studies were to investigate whether artesian well water containing natural bicarbonate (pH 8.8) might irreversibly denature (inactivate) human pepsin, and to establish its potential acid-buffering capacity. Laboratory studies were performed to determine whether human pepsin was inactivated by pH 8.8 alkaline water. In addition, the buffering capacity of the alkaline water was measured and compared to that of the two most popular commercially available bottled waters. The pH 8.8 alkaline water irreversibly inactivated human pepsin (in vitro), and its hydrochloric acid-buffering capacity far exceeded that of the conventional-pH waters. Unlike conventional drinking water, pH 8.8 alkaline water instantly denatures pepsin, rendering it permanently inactive. In addition, it has good acid-buffering capacity. Thus, the consumption of alkaline water may have therapeutic benefits for patients with reflux disease.

Tricyclic coumarin sulphonate derivatives with alkaline phosphatase inhibitory effects: in vitro and docking studies.

PubMed

Iqbal, Jamshed; El-Gamal, Mohammed I; Ejaz, Syeda Abida; Lecka, Joanna; Sévigny, Jean; Oh, Chang-Hyun

2018-12-01

Tissue-nonspecific alkaline phosphatase (TNAP) is an important isozyme of alkaline phosphatases, which plays different pivotal roles within the human body. Most importantly, it is responsible for maintaining the balanced ratio of phosphate and inorganic pyrophosphate, thus regulates the extracellular matrix calcification during bone formation and growth. The elevated level of TNAP has been linked to vascular calcification and end-stage renal diseases. Consequently, there is a need to search for highly potent and selective inhibitors of alkaline phosphatases (APs) for treatment of disorders associated with the over-expression of APs. Herein, a series of tricyclic coumarin sulphonate 1a-za with known antiproliferative activity, was evaluated for AP inhibition against human tissue nonspecific alkaline phosphatase (h-TNAP) and human intestinal alkaline phosphatase (h-IAP). The methylbenzenesulphonate derivative 1f (IC 50  = 0.38 ± 0.01 μM) was found to be the most active h-TNAP inhibitor. Another 4-fluorobenzenesulphonate derivative 1i (IC 50  = 0.45 ± 0.02 μM) was found as the strongest inhibitor of h-IAP. Some of the derivatives were also identified as highly selective inhibitors of APs. Detailed structure-activity relationship (SAR) was investigated to identify the functional groups responsible for the effective inhibition of AP isozymes. The study was also supported by the docking studies to rationalise the most possible binding site interactions of the identified inhibitors with the targeted enzymes.

Psyllium and fat in diets differentially affect the activities and expressions of colonic sphingomyelinases and caspase in mice.

PubMed

Cheng, Yajun; Ohlsson, Lena; Duan, Rui-Dong

2004-05-01

Dietary fibre and fat affect colonic tumourigenesis and inflammation. Sphingomyelin metabolism may have implications for the pathogenesis of colonic tumours and ulcerative colitis. The present study examined the effects of psyllium and fat on the enzymes responsible for sphingomyelin metabolism and apoptosis in the colon. Mice were fed control, psyllium-containing (100 g/kg), high-fat (313 g/kg, 53 % energy as fat) or high-fat plus psyllium diets for 4 weeks. The activities of acid, neutral and alkaline sphingomyelinase (SMase), neutral ceramidase, and caspase 3, 8 and 9 in colonic mucosa were determined. The expressions of alkaline SMase and caspase 3 were examined. The psyllium-containing diet was found to increase significantly the activities of alkaline SMase and caspase 3 and decreased those of acid SMase and neutral ceramidase. The high-fat diet had opposite effects on these enzymes and attenuated the effects of psyllium. Western blotting showed that psyllium increased and high-fat decreased the levels of alkaline SMase and caspase 3 in colonic mucosa. The change in caspase 3 activity was positively correlated with that of alkaline SMase and negatively with acid SMase. No similar changes of acid and alkaline phosphatase activities in the colon or acid and neutral SMase activity in the liver were identified. In conclusion, colonic sphingomyelin metabolism and apoptosis were affected by psyllium and fat in an opposite manner. The results may have implications for colorectal tumourigenesis and inflammation.

The Positive Regulatory Roles of the TIFY10 Proteins in Plant Responses to Alkaline Stress

PubMed Central

Zhu, Dan; Li, Rongtian; Liu, Xin; Sun, Mingzhe; Wu, Jing; Zhang, Ning; Zhu, Yanming

2014-01-01

The TIFY family is a novel plant-specific protein family, and is characterized by a conserved TIFY motif (TIFF/YXG). Our previous studies indicated the potential roles of TIFY10/11 proteins in plant responses to alkaline stress. In the current study, we focused on the regulatory roles and possible physiological and molecular basis of the TIFY10 proteins in plant responses to alkaline stress. We demonstrated the positive function of TIFY10s in alkaline responses by using the AtTIFY10a and AtTIFY10b knockout Arabidopsis, as evidenced by the relatively lower germination rates of attify10a and attify10b mutant seeds under alkaline stress. We also revealed that ectopic expression of GsTIFY10a in Medicago sativa promoted plant growth, and increased the NADP-ME activity, citric acid content and free proline content but decreased the MDA content of transgenic plants under alkaline stress. Furthermore, expression levels of the stress responsive genes including NADP-ME, CS, H+-ppase and P5CS were also up-regulated in GsTIFY10a transgenic plants under alkaline stress. Interestingly, GsTIFY10a overexpression increased the jasmonate content of the transgenic alfalfa. In addition, we showed that neither GsTIFY10a nor GsTIFY10e exhibited transcriptional activity in yeast cells. However, through Y2H and BiFc assays, we demonstrated that GsTIFY10a, not GsTIFY10e, could form homodimers in yeast cells and in living plant cells. As expected, we also demonstrated that GsTIFY10a and GsTIFY10e could heterodimerize with each other in both yeast and plant cells. Taken together, our results provided direct evidence supporting the positive regulatory roles of the TIFY10 proteins in plant responses to alkaline stress. PMID:25375909

The influence of spent household batteries to the organic fraction of municipal solid wastes during composting.

PubMed

Komilis, Dimitrios; Bandi, Dimitra; Kakaronis, Georgios; Zouppouris, Georgios

2011-06-01

The objective of this work was to investigate the potential transfer of 9 heavy metals from spent household batteries (zinc-carbon and alkaline-manganese batteries) to the organic fraction of municipal solid wastes during active composting. Six runs were performed including one control and 2 replications. Eleven types of alkaline and non-alkaline batteries were added at 3 different levels to the organic fraction of municipal solid wastes, namely at percentages equal to 0.98% w/w (low), 5.2% w/w (medium) and 10.6% w/w (high). Experiments were performed in 230 l insulated plastic aerobic bioreactors under a dynamic air flow regime for up to 60 days. Iron, copper and nickel masses contained in the organic fraction of the wastes were found significantly higher in the high level runs compared to the corresponding masses in the control. No metal transfer was obtained in the low and medium level runs. Metal mass balance closures ranged from 51% to 176%. Metals' concentrations in the leachates were below 10 mg l⁻¹ for most metals, except iron, while an increasing concentration trend versus time was measured in the leachates of the high level runs. In all cases, the contents of 5 regulated heavy metals in all end products were below the Hellenic limits. Copyright © 2011 Elsevier B.V. All rights reserved.

Experimental examination of the Mg-silicate-carbonate system at ambient temperature: Implications for alkaline chemical sedimentation and lacustrine carbonate formation

NASA Astrophysics Data System (ADS)

Tutolo, Benjamin M.; Tosca, Nicholas J.

2018-03-01

Despite their clear economic significance, Cretaceous presalt carbonates of the South Atlantic continental margins are not well-described by published facies models. This knowledge gap arises, in part, because the chemical processes that generate distinctive sedimentary products in alkaline, non-marine environments are poorly understood. Here, we use constraints inferred from reported mineralogical and geochemical features of presalt carbonate rocks to design and perform a suite of laboratory experiments to quantify the processes of alkaline chemical sedimentation. Using real-time observations of in-situ fluid chemistry, post-experiment analysis of precipitated solids, and geochemical modeling tools, we illustrate that spherulitic carbonates and Mg-silicate clays observed in presalt carbonates were likely precipitated from elevated pH (∼10-10.5) waters with high concentrations of silica and alkali cations typical of intermediate to felsic rocks, such as Na+ and K+. Charge balance constraints require that these cations were not counterbalanced to any significant degree by anions typical of seawater, such as Cl- and SO4-, which implies minimal seawater involvement in presalt deposition. Experimental data suggest that, at this alkaline pH, only modest concentrations (i.e., ∼0.5-1 mmol/kg) of Ca++ would have been required to precipitate spheroidal CaCO3. Given the rapid rates of CaCO3 nucleation and growth under such conditions, it is unlikely that Ca++ concentrations in lake waters ever exceeded these values, and sustained chemical fluxes are therefore required for extensive sediment accumulation. Moreover, our experiments indicate that the original mineralogy of presalt CaCO3 could have been calcite or aragonite, but the differing time scales of precipitation between CaCO3 and Mg-silicates would have tended to skew the Mg/Ca ratio in solution towards elevated values which favor aragonite. Mg-silicate nucleation and growth rates measured during our experiments suggest that elevated SiO2(aq) and high pH would have limited (to 1-2 mmol/kg) the Mg++ concentrations required to precipitate poorly crystalline Mg-silicates, which, through time, crystallize to minerals such as sepiolite and stevensite. Although our results provide robust constraints on the geochemistry of Mg-silicate-carbonate interactions during alkaline lake sedimentation, they leave open the potential for biological contributions to sedimentation within the presalt basins, as well as the hydrogeochemical mechanisms that maintained a productive carbonate factory of the scale observed along the South Atlantic margins.

High pH-Sensitive TRPA1 Activation in Odontoblasts Regulates Mineralization.

PubMed

Kimura, M; Sase, T; Higashikawa, A; Sato, M; Sato, T; Tazaki, M; Shibukawa, Y

2016-08-01

Calcium hydroxide and mineral trioxide aggregate are widely used for indirect and direct pulp capping and root canal filling. Their dissociation into Ca(2+) and OH(-) in dental pulp creates an alkaline environment, which activates reparative/reactionary dentinogenesis. However, the mechanisms by which odontoblasts detect the pH of the extracellular environment remain unclear. We examined the alkali-sensitive intracellular Ca(2+) signaling pathway in rat odontoblasts. In the presence or absence of extracellular Ca(2+), application of alkaline solution increased intracellular Ca(2+) concentration, or [Ca(2+)]i Alkaline solution-induced [Ca(2+)]i increases depended on extracellular pH (8.5 to 10.5) in both the absence and the presence of extracellular Ca(2+) The amplitude was smaller in the absence than in the presence of extracellular Ca(2+) Each increase in [Ca(2+)]i, activated by pH 7.5, 8.5, or 9.5, depended on extracellular Ca(2+) concentration; the equilibrium binding constant for extracellular Ca(2+) concentration decreased as extracellular pH increased (1.04 mM at pH 7.5 to 0.11 mM at pH 9.5). Repeated applications of alkaline solution did not have a desensitizing effect on alkali-induced [Ca(2+)]i increases and inward currents. In the presence of extracellular Ca(2+), alkaline solution-induced [Ca(2+)]i increases were suppressed by application of an antagonist of transient receptor potential ankyrin subfamily member 1 (TRPA1) channels. Ca(2+) exclusion efficiency during alkaline solution-induced [Ca(2+)]i increases was reduced by a Na(+)-Ca(2+) exchanger antagonist. Alizarin red and von Kossa staining revealed increased mineralization levels under repeated high pH stimulation, whereas the TRPA1 antagonist strongly reduced this effect. These findings indicate that alkaline stimuli-such as the alkaline environment inside dental pulp treated with calcium hydroxide or mineral trioxide aggregate-activate Ca(2+) mobilization via Ca(2+) influx mediated by TRPA1 channels and intracellular Ca(2+) release in odontoblasts. High pH-sensing mechanisms in odontoblasts are important for activating dentinogenesis induced by an alkaline environment. © International & American Associations for Dental Research 2016.

Hidden Markov analysis of mechanosensitive ion channel gating.

PubMed

Khan, R Nazim; Martinac, Boris; Madsen, Barry W; Milne, Robin K; Yeo, Geoffrey F; Edeson, Robert O

2005-02-01

Patch clamp data from the large conductance mechanosensitive channel (MscL) in E. coli was studied with the aim of developing a strategy for statistical analysis based on hidden Markov models (HMMs) and determining the number of conductance levels of the channel, together with mean current, mean dwell time and equilibrium probability of occupancy for each level. The models incorporated state-dependent white noise and moving average adjustment for filtering, with maximum likelihood parameter estimates obtained using an EM (expectation-maximisation) based iteration. Adjustment for filtering was included as it could be expected that the electronic filter used in recording would have a major effect on obviously brief intermediate conductance level sojourns. Preliminary data analysis revealed that the brevity of intermediate level sojourns caused difficulties in assignment of data points to levels as a result of over-estimation of noise variances. When reasonable constraints were placed on these variances using the better determined noise variances for the closed and fully open levels, idealisation anomalies were eliminated. Nevertheless, simulations suggested that mean sojourn times for the intermediate levels were still considerably over-estimated, and that recording bandwidth was a major limitation; improved results were obtained with higher bandwidth data (10 kHz sampled at 25 kHz). The simplest model consistent with these data had four open conductance levels, intermediate levels being approximately 20%, 51% and 74% of fully open. The mean lifetime at the fully open level was about 1 ms; estimates for the three intermediate levels were 54-92 micros, probably still over-estimates.

Long-term evolution of highly alkaline steel slag drainage waters.

PubMed

Riley, Alex L; Mayes, William M

2015-07-01

The disposal of slag generated by the steel industry can have negative consequences upon the surrounding aquatic environment by the generation of high pH waters, leaching of potentially problematic trace metals, and rapid rates of calcite precipitation which smother benthic habitats. A 36-year dataset was collated from the long-term ambient monitoring of physicochemical parameters and elemental concentrations of samples from two steel slag leachate-affected watercourses in northern England. Waters were typified by elevated pH (>10), high alkalinity, and were rich in dissolved metals (e.g. calcium (Ca), aluminium (Al), and zinc (Zn)). Long-term trend analysis was performed upon pH, alkalinity, and Ca concentration which, in addition to Ca flux calculations, were used to highlight the longevity of pollution arising as a result of the dumping and subsequent leaching of steel slags. Declines in calcium and alkalinity have been modest over the monitoring period and not accompanied by significant declines in water pH. If the monotonic trends of decline in alkalinity and calcium continue in the largest of the receiving streams, it will be in the region of 50-80 years before calcite precipitation would be expected to be close to baseline levels, where ecological impacts would be negligible.

Sensitivity of high-elevation streams in the Southern Blue Ridge Province to acidic deposition

USGS Publications Warehouse

Winger, P.V.; Lasier, P.J.; Hudy, M.; Fowler, D.; Van Den Avyle, M.J.

1987-01-01

The Southern Blue Ridge Province, which encompasses parts of northern Georgia, eastern Tennessee, and western North Carolina, has been predicted to be sensitive to impacts from acidic deposition, owing to the chemical composition of the bedrock geology and soils. This study confirms the predicted potential sensitivity, quantifies the level of total alkalinity and describes the chemical characteristics of 30 headwater streams of this area. Water chemistry was measured five times between April 1983 and June 1984 at first and third order reaches of each stream during baseflow conditions. Sensitivity based on total alkalinity and the Calcite Saturation Index indicates that the headwater streams of the Province are vulnerable to acidification. Total alkalinity and p11 were generally higher in third order reaches (mean, 72 ?eq/? and 6.7) than in first order reaches (64 ?eq/? and 6.4). Ionic concentrations were low, averaging 310 and 340 ?eq/? in first and third order reaches, respectively. A single sampling appears adequate for evaluating sensitivity based on total alkalinity, but large temporal variability requires multiple sampling for the detection of changes in pH and alkalinity over time. Monitoring of stream water should continue in order to detect any subtle effects of acidic deposition on these unique resource systems.

Dephosphorylation of microtubule-binding sites at the neurofilament-H tail domain by alkaline, acid, and protein phosphatases.

PubMed

Hisanaga, S; Yasugawa, S; Yamakawa, T; Miyamoto, E; Ikebe, M; Uchiyama, M; Kishimoto, T

1993-06-01

The dephosphorylation-induced interaction of neurofilaments (NFs) with microtubules (MTs) was investigated by using several phosphatases. Escherichia coli alkaline and wheat germ acid phosphatases increased the electrophoretic mobility of NF-H and NF-M by dephosphorylation, and induced the binding of NF-H to MTs. The binding of NFs to MTs was observed only after the electrophoretic mobility of NF-H approached the exhaustively dephosphorylated level when alkaline phosphatase was used. The number of phosphate remaining when NF-H began to bind to MTs was estimated by measuring phosphate bound to NF-H. NF-H did not bind to MTs even when about 40 phosphates from the total of 51 had been removed by alkaline phosphatase. The removal of 6 further phosphates finally resulted in the association of NF-H with MTs. A similar finding, that the restricted phosphorylation sites in the NF-H tail domain, but not the total amount of phosphates, were important for binding to MTs, was also obtained with acid phosphatases. In contrast to alkaline and acid phosphatases, four classes of protein phosphatases (protein phosphatases 1, 2A, 2B, and 2C) were ineffective for shifting the electrophoretic mobility of NF proteins and for inducing the association of NFs to MTs.

Effect of chronic hypo and hypervitaminosis C on the brush border enzymes and the intestinal uptake of glucose and alanine.

PubMed

Mahmood, A; Chauhan, V P; Lyall, V; Sarkar, A K

1979-08-15

Brush border sucrase and alkaline phosphatase activities are considerably enhanced in the intestine of ascorbic acid deficient guinea-pigs. Similar increase in the uptake of D-glucose and L-alanine also occurs in chronic vitamin C deficiency. However the permeability of D-glucose and L-alanine in the intestine of animals fed with large doses of vitamin C is severely depressed, with a reduction in the levels of sucrase and alkaline phosphatase activities.

Dietary phosphate restriction normalizes biochemical and skeletal abnormalities in a murine model of tumoral calcinosis.

PubMed

Ichikawa, Shoji; Austin, Anthony M; Gray, Amie K; Allen, Matthew R; Econs, Michael J

2011-12-01

Mutations in the GALNT3 gene cause tumoral calcinosis characterized by ectopic calcifications due to persistent hyperphosphatemia. We recently developed Galnt3 knockout mice in a mixed background, which had hyperphosphatemia with increased bone mineral density (BMD) and infertility in males. To test the effect of dietary phosphate intake on their phenotype, Galnt3 knockout mice were generated in the C57BL/6J strain and fed various phosphate diets: 0.1% (low), 0.3% (low normal), 0.6% (normal), and 1.65% (high). Sera were analyzed for calcium, phosphorus, alkaline phosphatase, creatinine, blood urine nitrogen, 1,25-dihydroxyvitamin D, osteocalcin, tartrate-resistant acid phosphatase 5b, and fibroblast growth factor 23 (Fgf23). Femurs were evaluated by dual-energy x-ray absorptiometry, dynamic histomorphometry, and/or microcomputed tomography. Galnt3 knockout mice in C57BL/6J had the same biochemical phenotype observed in our previous study: hyperphosphatemia, inappropriately normal 1,25-dihydroxyvitamin D level, decreased alkaline phosphatase activity, and low intact Fgf23 concentration but high Fgf23 fragments. Skeletal analyses of their femurs revealed significantly high BMD with increased cortical bone area and trabecular bone volume. On all four phosphate diets, Galnt3 knockout mice had consistently higher phosphorus levels and lower alkaline phosphatase and intact Fgf23 concentrations than littermate controls. The low-phosphate diet normalized serum phosphorus, alkaline phosphatase, and areal BMD but failed to correct male infertility in Galnt3 knockout mice. The high-phosphate diet did not increase serum phosphorus concentration in either mutant or control mice due to a compensatory increase in circulating intact Fgf23 levels. In conclusion, dietary phosphate restriction normalizes biochemical and skeletal phenotypes of Galnt3 knockout mice and, thus, can be an effective therapy for tumoral calcinosis.

Dietary Phosphate Restriction Normalizes Biochemical and Skeletal Abnormalities in a Murine Model of Tumoral Calcinosis

PubMed Central

Austin, Anthony M.; Gray, Amie K.; Allen, Matthew R.; Econs, Michael J.

2011-01-01

Mutations in the GALNT3 gene cause tumoral calcinosis characterized by ectopic calcifications due to persistent hyperphosphatemia. We recently developed Galnt3 knockout mice in a mixed background, which had hyperphosphatemia with increased bone mineral density (BMD) and infertility in males. To test the effect of dietary phosphate intake on their phenotype, Galnt3 knockout mice were generated in the C57BL/6J strain and fed various phosphate diets: 0.1% (low), 0.3% (low normal), 0.6% (normal), and 1.65% (high). Sera were analyzed for calcium, phosphorus, alkaline phosphatase, creatinine, blood urine nitrogen, 1,25-dihydroxyvitamin D, osteocalcin, tartrate-resistant acid phosphatase 5b, and fibroblast growth factor 23 (Fgf23). Femurs were evaluated by dual-energy x-ray absorptiometry, dynamic histomorphometry, and/or microcomputed tomography. Galnt3 knockout mice in C57BL/6J had the same biochemical phenotype observed in our previous study: hyperphosphatemia, inappropriately normal 1,25-dihydroxyvitamin D level, decreased alkaline phosphatase activity, and low intact Fgf23 concentration but high Fgf23 fragments. Skeletal analyses of their femurs revealed significantly high BMD with increased cortical bone area and trabecular bone volume. On all four phosphate diets, Galnt3 knockout mice had consistently higher phosphorus levels and lower alkaline phosphatase and intact Fgf23 concentrations than littermate controls. The low-phosphate diet normalized serum phosphorus, alkaline phosphatase, and areal BMD but failed to correct male infertility in Galnt3 knockout mice. The high-phosphate diet did not increase serum phosphorus concentration in either mutant or control mice due to a compensatory increase in circulating intact Fgf23 levels. In conclusion, dietary phosphate restriction normalizes biochemical and skeletal phenotypes of Galnt3 knockout mice and, thus, can be an effective therapy for tumoral calcinosis. PMID:22009723

Production, secretion, and stability of human secreted alkaline phosphatase in tobacco NT1 cell suspension cultures.

PubMed

Becerra-Arteaga, Alejandro; Mason, Hugh S; Shuler, Michael L

2006-01-01

Tobacco NT1 cell suspension cultures secreting active human secreted alkaline phosphatase (SEAP) were generated for the first time as a model system to study recombinant protein production, secretion, and stability in plant cell cultures. The SEAP gene encodes a secreted form of the human placental alkaline phosphatase (PLAP). During batch culture, the highest level of active SEAP in the culture medium (0.4 U/mL, corresponding to approximately 27 mg/L) was observed at the end of the exponential growth phase. Although the level of active SEAP decreased during the stationary phase, the activity loss did not appear to be due to SEAP degradation (based on Western blots) but due to SEAP denaturation. The protein-stabilizing agents polyvinylpirrolidone (PVP) and bacitracin were added extracellularly to test for their ability to reduce the loss of SEAP activity during the stationary phase. Bacitracin (100 mg/L) was the most effective treatment at sustaining activity levels for up to 17 days post-subculture. Commercially available human placental alkaline phosphatase (PLAP) was used to probe the mechanism of SEAP deactivation. Experiments with PLAP in sterile and conditioned medium corroborated the denaturation of SEAP by factors generated by cell growth and not due to simple proteolysis. We also show for the first time that the factors promoting activity loss are heat labile at 95 degrees C but not at 70 degrees C, and they are not inactivated after a 5 day incubation period under normal culture conditions (27 degrees C). In addition, there were no significant changes in pH or redox potential when comparing sterile and cell-free conditioned medium during PLAP incubation, indicating that these factors were unimportant.

Alkaline Phosphatase Protects Lipopolysaccharide-Induced Early Pregnancy Defects in Mice

PubMed Central

Lei, Wei; Ni, Hua; Herington, Jennifer; Reese, Jeff; Paria, Bibhash C.

2015-01-01

Excessive cytokine inflammatory response due to chronic or superphysiological level of microbial infection during pregnancy leads to pregnancy complications such as early pregnancy defects/loss and preterm birth. Bacterial toxin lipopolysaccharide (LPS), long recognized as a potent proinflammatory mediator, has been identified as a risk factor for pregnancy complications. Alkaline phosphatase (AP) isozymes have been shown to detoxify LPS by dephosphorylation. In this study, we examined the role of alkaline phosphatase (AP) in mitigating LPS-induced early pregnancy complications in mice. We found that 1) the uterus prior to implantation and implantation sites following embryo implantation produce LPS recognition and dephosphorylation molecules TLR4 and tissue non-specific AP (TNAP) isozyme, respectively; 2) uterine TNAP isozyme dephosphorylates LPS at its sites of production; 3) while LPS administration following embryo implantation elicits proinflammatory cytokine mRNA levels at the embryo implantation sites (EISs) and causes early pregnancy loss, dephosphorylated LPS neither triggers proinflammatory cytokine mRNA levels at the EISs nor induces pregnancy complications; 4) AP isozyme supplementation to accelerate LPS detoxification attenuates LPS-induced pregnancy complications following embryo implantation. These findings suggest that a LPS dephosphorylation strategy using AP isozyme may have a unique therapeutic potential to mitigate LPS- or Gram-negative bacteria-induced pregnancy complications in at-risk women. PMID:25910276

Alkaline phosphatase protects lipopolysaccharide-induced early pregnancy defects in mice.

PubMed

Lei, Wei; Ni, Hua; Herington, Jennifer; Reese, Jeff; Paria, Bibhash C

2015-01-01

Excessive cytokine inflammatory response due to chronic or superphysiological level of microbial infection during pregnancy leads to pregnancy complications such as early pregnancy defects/loss and preterm birth. Bacterial toxin lipopolysaccharide (LPS), long recognized as a potent proinflammatory mediator, has been identified as a risk factor for pregnancy complications. Alkaline phosphatase (AP) isozymes have been shown to detoxify LPS by dephosphorylation. In this study, we examined the role of alkaline phosphatase (AP) in mitigating LPS-induced early pregnancy complications in mice. We found that 1) the uterus prior to implantation and implantation sites following embryo implantation produce LPS recognition and dephosphorylation molecules TLR4 and tissue non-specific AP (TNAP) isozyme, respectively; 2) uterine TNAP isozyme dephosphorylates LPS at its sites of production; 3) while LPS administration following embryo implantation elicits proinflammatory cytokine mRNA levels at the embryo implantation sites (EISs) and causes early pregnancy loss, dephosphorylated LPS neither triggers proinflammatory cytokine mRNA levels at the EISs nor induces pregnancy complications; 4) AP isozyme supplementation to accelerate LPS detoxification attenuates LPS-induced pregnancy complications following embryo implantation. These findings suggest that a LPS dephosphorylation strategy using AP isozyme may have a unique therapeutic potential to mitigate LPS- or Gram-negative bacteria-induced pregnancy complications in at-risk women.

Osteomalacia complicating renal tubular acidosis in association with Sjogren's syndrome.

PubMed

El Ati, Zohra; Fatma, Lilia Ben; Boulahya, Ghada; Rais, Lamia; Krid, Madiha; Smaoui, Wided; Maiz, Hedi Ben; Beji, Soumaya; Zouaghi, Karim; Moussa, Fatma Ben

2014-09-01

Renal involvement in Sjogren's syndrome (SS) is not uncommon and may precede other complaints. Tubulointerstitial nephritis is the most common renal disease in SS and may lead to renal tubular acidosis (RTA), which in turn may cause osteomalacia. Nevertheless, osteomalacia rarely occurs as the first manifestation of a renal tubule disorder due to SS. We herewith describe a 43-year-old woman who was admitted to our hospital for weakness, lumbago and inability to walk. X-ray of the long bones showed extensive demineralization of the bones. Laboratory investigations revealed chronic kidney disease with serum creatinine of 2.3 mg/dL and creatinine clearance of 40 mL/min, hypokalemia (3.2 mmol/L), hypophosphatemia (0.4 mmol/L), hypocalcemia (2.14 mmol/L) and hyperchloremic metabolic acidosis (chlorine: 114 mmol/L; alkaline reserve: 14 mmol/L). The serum alkaline phosphatase levels were elevated. The serum levels of 25-hydroxyvitamin D and 1,25-dihydroxy vitamin D were low and borderline low, respectively, and the parathyroid hormone level was 70 pg/L. Urinalysis showed inappropriate alkaline urine (urinary PH: 7), glycosuria with normal blood glucose, phosphaturia and uricosuria. These values indicated the presence of both distal and proximal RTA. Our patient reported dryness of the mouth and eyes and Schirmer's test showed xerophthalmia. An accessory salivary gland biopsy showed changes corresponding to stage IV of Chisholm and Masson score. Kidney biopsy showed diffuse and severe tubulo-interstitial nephritis with dense lymphoplasmocyte infiltrates. Sicca syndrome and renal interstitial infiltrates indicated SS as the underlying cause of the RTA and osteomalacia. The patient received alkalinization, vitamin D (Sterogyl ®), calcium supplements and steroids in an initial dose of 1 mg/kg/day, tapered to 10 mg daily. The prognosis was favorable and the serum creatinine level was 1.7 mg/dL, calcium was 2.2 mmol/L and serum phosphate was 0.9 mmol/L.

Methyltestosterone-induced cholestasis. The importance of disproportionately low serum alkaline phosphatase level.

PubMed

Borhan-Manesh, F; Farnum, J B

1989-09-01

We describe a 64-year-old man who developed cholestatic jaundice after receiving 20 to 40 mg of methyltestosterone daily for 6 months for impotence but failed to mention it as part of his drug history. He underwent endoscopic retrograde and papillotomy before a positive history for methyltestosterone ingestion could be obtained. Since methyltestosterone is most often used for sexual impotence, the patient may be quite reluctant to mention this hormone as part of his medication. A normal or mildly elevated alkaline phosphatase level, disproportionate to the level of hyperbilirubinemia seen in this patient and in all previous reports, appears to be characteristic of this phenomenon. This pattern of liver function abnormality can be a clue to suspect methyltestosterone as the causative agent and spare the patient unneeded expensive noninvasive and potentially harmful invasive procedures.

Spectral engineering of optical fiber through active nanoparticle doping

NASA Astrophysics Data System (ADS)

Lindstrom-James, Tiffany

The spectral engineering of optical fiber is a method of intentional doping of the core region in order to absorb/emit specific wavelengths of light therby providing enhanced performance over current fibers. Efforts here focused on developing an understanding of optically active nanoparticles based on alkaline earth fluorides that could be easily and homogeneously incorporated into the core of a silica based optical fiber preform and result in efficient and tailorable spectral emissions. Doped and undoped calcium, strontium and barium fluoride nanoparticles were successfully synthesized and characterized for their physical, chemical, and optical behavior. Distinct spectroscopic differences as a result of different host materials, varying rare earth doping levels and processing conditions, indicated the ability to influence the spectral behavior of the doped nanoparticle. By using photoluminescence to predict diffusion behavior, the application of a simple one dimensional model for diffusion provided a method for predicting the diffusion coefficient of europium ions in alkaline earth fluorides with order of magnitude accuracy. Modified chemical vapor deposition derived silica preforms were individually solution doped with europium doped alkaline earth fluoride nanoparticles. By using the rare earth doped alkaline earth fluoride nanoparticles as the dopant materials in the core of optical fiber preforms, the resultant optical properties of the glass were significantly influenced by their presence in the core. The incorporation of these rare earth doped alkaline earth fluoride nanoparticles was found to significantly influence the local chemical and structural environment about the rare earth ion, demonstrated homogeneity and uniform distribution of the rare earth dopant and resulted in specifically unique spectral behavior when compared to conventional doping methods. A more detailed structural model of the doped core glass region has been developed based on the spectral behavior of these active fiber preforms. It has been shown that rare earth doping of alkaline earth fluoride nanoparticles provides a material which can be 'tuned' to specific applications through the use of different host materials, processing conditions and doping levels of the rare earth and when used as dopant materials for active optical fibers, provides a means to tailor the optical behavior.

Environmental exposure to human carcinogens in teenagers and the association with DNA damage

DOE Office of Scientific and Technical Information (OSTI.GOV)

Franken, Carmen, E-mail: carmen.franken@vito.be

Background: We investigated whether human environmental exposure to chemicals that are labeled as (potential) carcinogens leads to increased (oxidative) damage to DNA in adolescents. Material and methods: Six hundred 14–15-year-old youngsters were recruited all over Flanders (Belgium) and in two areas with important industrial activities. DNA damage was assessed by alkaline and formamidopyrimidine DNA glycosylase (Fpg) modified comet assays in peripheral blood cells and analysis of urinary 8-hydroxydeoxyguanosine (8-OHdG) levels. Personal exposure to potentially carcinogenic compounds was measured in urine, namely: chromium, cadmium, nickel, 1-hydroxypyrene as a proxy for exposure to other carcinogenic polycyclic aromatic hydrocarbons (PAHs), t,t-muconic acid asmore » a metabolite of benzene, 2,5-dichlorophenol (2,5-DCP), organophosphate pesticide metabolites, and di(2-ethylhexyl) phthalate (DEHP) metabolites. In blood, arsenic, polychlorinated biphenyl (PCB) congeners 118 and 156, hexachlorobenzene (HCB), dichlorodiphenyltrichloroethane (DDT) and perfluorooctanoic acid (PFOA) were analyzed. Levels of methylmercury (MeHg) were measured in hair. Multiple linear regression models were used to establish exposure-response relationships. Results: Biomarkers of exposure to PAHs and urinary chromium were associated with higher levels of both 8-OHdG in urine and DNA damage detected by the alkaline comet assay. Concentrations of 8-OHdG in urine increased in relation with increasing concentrations of urinary t,t-muconic acid, cadmium, nickel, 2,5-DCP, and DEHP metabolites. Increased concentrations of PFOA in blood were associated with higher levels of DNA damage measured by the alkaline comet assay, whereas DDT was associated in the same direction with the Fpg-modified comet assay. Inverse associations were observed between blood arsenic, hair MeHg, PCB 156 and HCB, and urinary 8-OHdG. The latter exposure biomarkers were also associated with higher fish intake. Urinary nickel and t,t-muconic acid were inversely associated with the alkaline comet assay. Conclusion: This cross-sectional study found associations between current environmental exposure to (potential) human carcinogens in 14–15-year-old Flemish adolescents and short-term (oxidative) damage to DNA. Prospective follow-up will be required to investigate whether long-term effects may occur due to complex environmental exposures. - Highlights: • Exposure to (potential) carcinogens is associated with (oxidative) damage to DNA. • Most associations of exposures are with urinary 8-OHdG. • 1-Hydroxypyrene and chromium are associated with the comet assay and 8-OHdG. • PFOA is associated with higher levels of DNA damage in the alkaline comet assay.« less

Mode of de-esterification of alkaline and acidic pectin methyl esterases at different pH conditions.

PubMed

Duvetter, Thomas; Fraeye, Ilse; Sila, Daniel N; Verlent, Isabel; Smout, Chantal; Hendrickx, Marc; Van Loey, Ann

2006-10-04

Highly esterified citrus pectin was de-esterified at pH 4.5 and 8.0 by a fungal pectin methyl esterase (PME) that was shown to have an acidic isoelectric pH (pI) and an acidic pH optimum and by a plant PME that was characterized by an alkaline pI and an alkaline pH optimum. Interchain and intrachain de-esterification patterns were studied by digestion of the pectin products with endo-polygalacturonase and subsequent analysis using size exclusion and anion-exchange chromatography. No effect of pH was observed on the de-esterification mode of either of the two enzymes. Acidic, fungal PME converted pectin according to a multiple-chain mechanism, with a limited degree of multiple attack at the intrachain level, both at pH 4.5 and at pH 8.0. A multiple-attack mechanism, with a high degree of multiple attack, was more appropriate to describe the action mode of alkaline, plant PME, both at pH 4.5 and at pH 8.0.

Prospects for transferring 87Rb84Sr dimers to the rovibrational ground state based on calculated molecular structures

NASA Astrophysics Data System (ADS)

Chen, Tao; Zhu, Shaobing; Li, Xiaolin; Qian, Jun; Wang, Yuzhu

2014-06-01

Using fitted model potential curves of the ground and lowest three excited states yielded by the relativistic Kramers-restricted multireference configuration interaction method with 19 electrons correlated, we theoretically investigate the rovibrational properties including the number of vibrational state and diagonally distributed Franck-Condon factors for a 87Rb84Sr molecule. Benefiting from a turning point at about v'=20 for the Franck-Condon factors between the ground state and spin-orbit 2(Ω=1/2) excited state, we choose |2(Ω=1/2),v'=21,J'=1> as the intermediate state in the three-level model to theoretically analyze the possibility of performing stimulated Raman adiabatic passage to transfer weakly bound RbSr molecules to the rovibrational ground state. With 1550 nm pump laser (2 W/cm2) and 1342 nm dump laser (10 mW/cm2) employed and appropriate settings of pulse time length (about 300 μs), we have formalistically achieved a round-trip transfer efficiency of 60%, namely 77% for one-way transfer. The results demonstrate the possibility of producing polar 87Rb84Sr molecules efficiently in a submicrokelvin regime, and further provide promising directions for future theoretical and experimental studies on alkali-alkaline(rare)-earth dimers.

Thermal degradation of hexachlorobenzene in the presence of calcium oxide at 340-400 °C.

PubMed

Yin, Keqing; Gao, Xingbao; Sun, Yifei; Zheng, Lei; Wang, Wei

2013-11-01

Hexachlorobenzene (HCB) in the milligram range was co-heated with calcium oxide (CaO) powder in sealed glass ampoules at 340-400 °C. The heated samples were characterized and analyzed by Raman spectroscopy, elemental analysis, gas chromatography/mass spectrometry, ion chromatography, and thermal/optical carbon analysis. The degradation products of HCB were studied at different temperatures and heated times. The amorphous carbon was firstly quantitatively evaluated and was thought to be important fate of the C element of HCB. The yield of amorphous carbon in products increased with heating time, for samples treated for 8h at 340, 380 °C and 400 °C, the value were 17.5%, 34.8% and 50.2%, respectively. After identification of the dechlorination products, the HCB degradation on CaO at 340-400 °C was supposed to through dechlorination/polymerization pathway, which is induced by electron transfer, generate chloride ions and form high-molecular weight intermediates with significant levels of both hydrogen and chlorine, and finally form amorphous carbon. Higher temperature was beneficial for the dechlorination/polymerization efficiency. The results are helpful for clarifying the reaction mechanism for thermal degradation of chlorinated aromatics in alkaline matrices. Copyright © 2013 Elsevier Ltd. All rights reserved.

Selective biotinylation of Neisseria meningitidis group B capsular polysaccharide and application in an improved ELISA for the detection of specific antibodies.

PubMed

Diaz Romero, J; Outschoorn, I

1993-03-15

A method is described for the selective biotinylation of meningococcal capsular polysaccharide from Neisseria meningitidis group B and its application to an enzyme-linked immunoabsorbent assay (ELISA) to detect specific antibodies by immobilization on streptavidin-coated microtiter wells. Capsular polysaccharide from Neisseria meningitidis B has been biotinylated by specific periodate oxidation of terminal residues and condensation of the resulting aldehydes with biotin hydrazide, using a spin-column technique in the intermediate purification steps. The ELISA was optimized employing an extended reaction time between the label alkaline phosphatase and its most common substrate, p-nitrophenyl phosphate, together with evaluation of blocking agents to minimize non-specific binding. Specificity was demonstrated by a direct competitive enzyme immunoassay (EIA).

Nicotinic Acid Metabolism, V. A Cobamide Coenzyme-Dependent Conversion of α-Methyleneglutaric Acid to Dimethylmaleic Acid

PubMed Central

Kung, H. F.; Cederbaum, S.; Tsai, L.; Stadtman, T. C.

1970-01-01

A new B12-coenzyme-dependent isomerization, catalyzed by extracts of a nicotinate-fermenting clostridium, results in the conversion of α-methyleneglutaric acid to dimethylmaleic acid. These two acids are intermediates in the multistep anaerobic process wherein nicotinate is converted, ultimately, to one mole each of propionate, acetate, carbon dioxide, and ammonia. Dimethylmaleic acid reacts in its anhydride form with 2,4-dinitrophenylhydrazine to form N-2′,4′-dinitrophenyl-anilino-3,4-dimethylmaleimide. The characteristic reddish color exhibited by the latter derivative in alkaline solution serves as a convenient quantitative assay for dimethylmaleic acid. Comparison of the 2,4-dinitrophenylhydrazine derivatives of the product of the enzymic reaction and of synthetic dimethylmaleic anhydride showed them to be identical in every respect. PMID:5266166

Densification of LSGM electrolytes using activated microwave sintering

NASA Astrophysics Data System (ADS)

Kesapragada, S. V.; Bhaduri, S. B.; Bhaduri, S.; Singh, P.

Lanthanum gallate doped with alkaline rare earths (LSGM) powders were densified using an activated microwave sintering process for developing a dense stable electrolyte layer for applications in intermediate temperature-solid oxide fuel cells (IT-SOFCs). Due to heat generation in situ, the process of sintering gets activated with faster kinetics compared to a conventional sintering process. The effect of various microwave process parameters on the microstructure and phase formation was studied. The sintered pellets were characterized using scanning electron microscopy-energy dispersive analysis (SEM-EDAX), and X-ray diffraction (XRD). The density of LSGM pellets microwave sintered at 1350 °C for 20 min is greater than 95% theoretical density with a fine grained microstructure (˜2-3 μm) and without the presence of other phase(s).

Assessment of the serum levels of bone alkaline phosphatase with a new immunoradiometric assay in patients with metabolic bone disease

DOE Office of Scientific and Technical Information (OSTI.GOV)

Garnero, P.; Delmas, P.D.

1993-10-01

The authors measured serum bone alkaline phosphatase (B-ALP) with a new immunoradiometric assay (IRMA) in a large sample of healthy controls comprising 173 women and 180 men, 20-88 yr of age, and in patients with metabolic bone disease. Using serum samples from patients with liver disease and patients with Paget's disease with elevated total alkaline phosphatase (T-ALP) as a source of, respectively, liver and bone isoenyzmes, they determined a liver cross-reactivity of the IRMA of 16% that was confirmed by electrophoresis of the circulating alkaline phosphatase isoenzymes. The IRMA was linear for serial sample dilutions, the recovery ranged from 89-110%,more » and the intra- and interassay variations were below 7% and 9%, respectively. B-ALP increased linearly with age in both sexes, and the mean B-ALP serum levels were not significantly different for women and men (11.3 [+-] 4.8 ng/mL for women; 11.0 [+-] 4.0 ng/mL for men). The increase in B-ALP after the menopause was significantly higher than that in T-ALP (+77% vs. +24%; P<0.001). When the values of postmenopausal women were expressed as the SD from the mean of premenopausal women, the mean Z scores were 2.2[+-] 1.8 for B-ALP and 0.9 [+-] 1.3 for T-ALP (P<0.001 between the two).« less

Salivary alkaline phosphatase and calcium in caries-active type II diabetes mellitus patients: An in vivo study

PubMed Central

Hegde, Mithra N.; Tahiliani, Divya; Shetty, Shilpa; Devadiga, Darshana

2014-01-01

Background: Diabetes Mellitus is a metabolic syndrome, affecting the oral health in various ways with dental caries being one of the most common problems encountered. Saliva is one of the most abundant secretions in the human body with a variety of natural protective and defence molecules bathing the oral cavity maintaining equilibrium. Its collection is easy and non-invasive. Aims: To compare and evaluate salivary alkaline phosphatase levels and calcium ion levels between caries active type II diabetes mellitus patients and non-diabetics. Materials and Methods: This study was carried out on caries-active age and gender matched 60 non-diabetic and 60 patients with known Type II diabetes mellitus subjects of age group 25-50 years with DMFT index >10. Saliva sample was collected to analyse for alkaline phosphatase enzyme and concentration of calcium ions using Agappe kits. Statistical Analysis: Student ‘t’ test was used to correlate the salivary electrolyte concentration in non- diabetic and diabetic patients with dental caries. A ‘P’ value of 0.05 or less was considered significant. Results are presented as mean ± standard deviation (X ± SD). Results: The alkaline phosphatase (ALP) activity in saliva was higher in diabetic patients when compared to that of non-diabetic patients with salivary calcium ions were significantly higher in non-diabetic individuals. Conclusion: Diabetes Mellitus patients are more prone to dental caries, hence require intervention to improve the quality of saliva. PMID:25395756

New Insights to the Mid Miocene Calc-alkaline Lavas of the Strawberry Volcanics, NE Oregon Surrounded by the Coeval Tholeiitic Columbia River Basalt Province

NASA Astrophysics Data System (ADS)

Steiner, A. R.; Streck, M. J.

2013-12-01

The Strawberry Volcanics (SV) of NE Oregon were distributed over 3,400 km2 during the mid-Miocene and comprise a diverse volcanic suite, which span the range of compositions from basalt to rhyolite. The predominant composition of this volcanic suite is calc-alkaline (CA) basaltic andesite and andesite, although tholeiitic (TH) lavas of basalt to andesite occur as well. The coeval flood basalts of the Columbia River province surround the SV. Here we will discuss new ages and geochemical data, and present a new geologic map and stratigraphy of the SV. The SV are emplaced on top of pre-Tertiary accreted terranes of the Blue Mountain Province, Mesozoic plutonic rocks, and older Tertiary volcanic rocks thought to be mostly Oligocene of age. Massive rhyolites (~300 m thick) are exposed mainly along the western flank and underlie the intermediate composition lavas. In the southern portion of this study area, alkali basaltic lavas, thought to be late Miocene to early Pliocene in age, erupted and overlie the SV. In addition, several regional ignimbrites reach into the area. The 9.7 Ma Devine Canyon Tuff and the 7.1 Ma Rattlesnake Tuff also overlie the SV. The 15.9-15.4 Ma Dinner Creek Tuff is mid-Miocene, and clear stratigraphic relationships are found in areas where the tuff is intercalated between thick SV lava flows. All of the basalts of the SV are TH and are dominated by phenocryst-poor (≤2%) lithologies. These basalts have an ophitic texture dominated by plagioclase, clinopyroxene and olivine (often weathered to iddingsite). Basalts and basaltic andesites have olivine Fo #'s ranging from 44 at the rims (where weathered to iddingsite) and as high as 88 at cores. Pyroxene Mg #'s range from 65 to 85. Andesites of the SV are sub-alkaline, and like the basalts, are exceedingly phenocryst-poor (≤3%) with microphenocrysts of plagioclase and lesser pyroxene and olivine, which occasionally occur as crystal clots of ~1-3 mm instead of single crystals. In addition, minimal intermediate lavas are phenocryst-rich (~25%), containing plagioclase, olivine, and pyroxene. However, phenocrysts in these lavas are strongly zoned and resorbed, and in general, these lavas are volumetrically insignificant compared with the phenocrysts-poor andesites. The CA andesites have olivine Fo #'s that range from 78 to 84 at the cores. Pyroxene Mg #'s range from 41 to 66 near rims and 80 to 84 in the cores. These values mimic the values for of the TH parental basalts of the SV, giving further testament that the CA intermediate lavas were derived from parental TH basalt. Our interpretation of these data is that the SV are the product of hot-spot-related, basaltic magmas interacting with the continental crust. The transition from TH to CA lavas may be generated by the interaction of basaltic lavas of CRBG type with the crustal melts that produced the Strawberry Mountain Rhyolites. Using AFC geochemical modeling, we can show that if we begin with an average Steens basalt composition and introduce the rhyolites, then we can reproduce the observed TH to CA trend. Furthermore, CA andesites (>60% SiO2) have high Fo and Mg #'s (~84), which mimic the TH basaltic lavas of the SV.

Assessment of tolerant sunfish populations (Lepomis sp.) inhabiting selenium-laden coal ash effluents. 2. Tissue biochemistry evaluation.

PubMed

Lohner, T W; Reash, R J; Williams, M

2001-11-01

Sunfish were collected from a fly ash pond-receiving stream and an Ohio River reference site to assess biochemical responses to coal ash effluent exposure. Selenium levels in sunfish from the receiving stream were higher than toxic thresholds associated with adverse population effects and reproductive impairment. Tissue biochemistry was found to be indicative of metal exposure and effect, but varied widely. Liver glycogen was positively correlated with increased liver metal levels, indicating no adverse effect upon stored carbohydrate levels. Lipid levels decreased with increasing metals, indicating possible nutritional stress. Protein levels increased with increasing metal levels, possibly due to the synthesis of proteins to sequester the metals. ATPase, dUTPase, and alkaline phosphatase activity generally decreased with exposure to ash pond metals, but remained within normal physiological ranges. Fish condition factors and liver somatic indices were correlated with liver lipid levels, dUTPase activity, and gill ATPase and alkaline phosphatase activity. Exposure to coal ash effluents produced biochemical markers of exposure that were associated with fish condition indicators; however, the indices themselves were not significantly affected by effluent exposure.

Effects of Water Level on Three Wetlands Soil Seed Banks on the Tibetan Plateau

PubMed Central

Ma, Miaojun; Ma, Zhen; Du, Guozhen

2014-01-01

Background Although the effect of water level on germination in soil seed banks has been documented in many ecosystems, the mechanism is not fully understood, and to date no empirical studies on this subject exist. Further, no work has been done on the effect of water level on seed banks of drying and saline-alkaline wetlands in alpine areas on the Tibetan Plateau. Methodology We examined the effects of water level (0 cm, 5 cm and 10 cm) on seed germination and seedling establishment from soil seed banks at 0–5 cm and 5–10 cm depths in typical, drying, and saline-alkaline wetlands. We also explore the potential role of soil seed bank in restoration of drying and saline-alkaline wetlands. Principal Findings Species richness decreased with increase in water level, but there almost no change in seed density. A huge difference exists in species composition of the seed bank among different water levels in all three wetlands, especially between 0 cm and 5 cm and 0 cm and 10 cm. Similarity of species composition between seed bank and plant community was higher in 0 cm water level in drying wetland than in the other two wetlands. The similarity was much higher in 0 cm water level than in 5 cm and 10 cm water levels in all three wetlands. Species composition of the alpine wetland plant community changed significantly after drying and salinization, however, species composition of the seed bank was unchanged regardless of the environment change. Conclusions/Significance Water level greatly affects seed bank recruitment and plant community establishment. Further, different water levels in restored habitats are likely to determine its species composition of the plant community. The seed bank is important in restoration of degraded wetlands. Successful restoration of drying and salinization wetlands could depend on the seed bank. PMID:24984070

Highly precise Re-Os dating for molybdenite using alkaline fusion and NTIMS.

PubMed

Markey, R; Stein, H; Morgan, J

1998-03-01

The technique described in this paper represents the modification and combination of two previously existing methods, alkaline fusion and negative thermal ion mass spectrometry (NTIMS). We have used this technique to analyze repeatedly a homogeneous molybdenite powder used as a reference standard in our laboratory. Analyses were made over a period of 18 months, using four different calibrations of two different spike solutions. The age of this standard reproduces at a level of +/-0.13%. Each individual age analysis carries an uncertainty of about 0.4% that includes the uncertainty in the decay constant for (187)Re. This new level of resolution has allowed us to recognize real differences in ages for two grain-size populations of molybdenite from some Archean samples.

Highly precise Re-Os dating for molybdenite using alkaline fusion and NTIMS

USGS Publications Warehouse

Markey, R.; Stein, H.; Morgan, J.

1998-01-01

The technique described in this paper represents the modification and combination of two previously existing methods, alkaline fusion and negative thermal ion mass spectrometry (NTIMS). We have used this technique to analyze repeatedly a homogeneous molybdenite powder used as a reference standard in our laboratory. Analyses were made over a period of 18 months, using four different calibrations of two different spike solutions. The age of this standard reproduces at a level of ?? 0.13%. Each individual age analysis carries an uncertainty of about 0.4% that includes the uncertainty in the decay constant for 187Re. This new level of resolution has allowed us to recognize real differences in ages for two grain-size populations of molybdenite from some Archean samples.

Effects of parsley (Petroselinum crispum) on the liver of diabetic rats: a morphological and biochemical study.

PubMed

Bolkent, S; Yanardag, R; Ozsoy-Sacan, O; Karabulut-Bulan, O

2004-12-01

Parsley is used by diabetics in Turkey to reduce blood glucose. The present study aims to investigate both the morphological and biochemical effects of parsley on liver tissue. Rat hepatocytes were examined by light and electron microscopy. Degenerative changes were observed in the hepatocytes of diabetic rats. These degenerative changes were significantly reduced or absent in the hepatocytes of diabetic rats treated with parsley. Blood glucose levels, alanine transaminase and alkaline phosphatase were observed to be raised in diabetic rats. Diabetic rats treated with parsley demonstrated significantly lower levels of blood glucose, alanine transaminase and alkaline phosphatase. The present study suggests that parsley demonstrates a significant hepatoprotective effect in diabetic rats. 2004 John Wiley & Sons, Ltd.

Osteo-dental fluorosis in relation to chemical constituents of drinking waters.

PubMed

Choubisa, S L

2012-01-01

Study was conducted in 17 fluoride endemic villages to find out association between the prevalence and severity of osteo-dental fluorosis with different chemical constituents of drinking waters. These villages were arranged in 7 sets, each containing 2 to 3 villages with identical mean fluoride (F) concentrations in the range 1.0 to 5.8 mg/L but having different mean values of total hardness, alkalinity and nitrate (NO3) content in drinking water sources. A close association or relationship was found between the prevalence of fluorosis and the total hardness and alkalinity of potable waters. A low prevalence of fluorosis was found at low alkalinity and at high total hardness. But no specific association was observed between the prevalence figures of fluorosis with pH and NO3 levels which is also discussed in the present communication.

A Geochemical Comparison of the Northern Peninsular Ranges Batholith in Southern California and the Coastal Batholith in Southern Peru

NASA Astrophysics Data System (ADS)

Clausen, B. L.; Martínez Ardila, A. M.; Morton, D. M.

2010-12-01

An extensive geochemical data set from the northern Peninsular Ranges Batholith (PRB) in southern California is compared and contrasted with the Arequipa segment of the Peruvian Coastal Batholith, including new granitoid samples recently collected near Ica (14°S, 76°W). The data include major and trace elements and Sr isotope ratios. This is part of an on-going study of subduction-related magmatism to refine a petrogenetic model of crust formation at plate boundaries, with a particular interest in the role of magma mixing. Research in the northern PRB suggests that continental crust is formed in several cycles: (1) mantle melting to give mafic volcanics and gabbroic intrusives, (2) basalt/gabbro melting to give felsic granitoids uncontaminated by continental crust and having low initial 87Sr/86Sr (Sri) values less than 0.704, and (3) crustal melting to give high Sri values greater than 0.704. Geochemical evidence was used to determine the extent of mixing between mafic and felsic magma that produced rocks of intermediate SiO2 composition. These differentiation cycles formed a west to east chronologic sequence and yielded granitoids of gabbro, tonalite, and granodiorite composition. Using principal component analysis on the northern PRB granitoids, the four factors affecting geochemical composition were categorized as differentiation, crustal contamination, depth of magma source, and conditions that yield a range from calcic to more alkaline granitoids. A similar major and trace element analysis is being done for a classic result of subduction in the Peruvian Coastal Batholith. The Peruvian samples recently collected include granitoids of the upper Cretaceous Coastal Batholith, as well as the associated volcanics of Cretaceous and Jurassic age. The Coastal Batholith samples include a range of granitoids from the early gabbros and from the four batholithic super-units (from west to east: Linga, Pampahuasi, Tiabaya, and Incahuasi) containing a combination of diorite, tonalite, monzonite, and granodiorite. In addition, samples were taken from the adjacent Precambrian basement and Paleozoic San Nicolas batholith in order to estimate the local geochemistry for continental crust contamination and to compare with published crustal averages. For this part of the Coastal Batholith, gabbroic plutons that formed during extension have little contamination from continental crust; the time-separated super-units form distinct assemblages; some of the super-units went through several differentiation cycles; parts of the Linga super-unit have low Sri ratios below 0.704; and magma mixing played an important role. The Coastal Batholith of western Peru (similar to the eastern PRB) has an intermediate calc-alkaline composition, in comparison to batholiths in Chile (similar to the western PRB) that are more calcic and those in eastern Peru (similar to the Sierra Nevadas) that are more alkaline.

The identification of selected vegetation types in Arizona through the photointerpretation of intermediate scale aerial photography. M.S. Thesis

NASA Technical Reports Server (NTRS)

Ross, G. F. (Principal Investigator)

1973-01-01

The author has identified the following significant results. Nine photography interpretation tests were performed with a total of 19 different interpreters. Three tests were conducted with black and white intermediate scale photography and six tests with color infrared intermediate scale photography. The black and white test results show that the interpretation of vegetation mapped at the association level of classification is reliable for all the classes used at 61%. The color infrared tests indicate that the association level of mapping is unsatisfactory for vegetation interpretation of classes 1 and 6. Students' t-test indicated that intermediate scale black and white photography is significantly better than this particular color infrared photography for the interpretation of southeastern Arizona vegetation mapped at the association level.

Effects of Escherichia coli challenge and transport stress on hematology and serum chemistry values of three genetic lines of turkeys.

PubMed

Huff, G R; Huff, W E; Rath, N C; Anthony, N B; Nestor, K E

2008-11-01

Three lines of turkeys were compared for response to an Escherichia coli challenge followed by transport stress (transport). The turkey lines were a slow-growing line selected for increased egg production (egg line), a fast-growing line selected for increased 16-wk BW (F line), and a commercial line (Comm line). Birds were challenged at 14 wk of age with an air sac injection of 5,000 to 10,000 cfu of E. coli. At 8 d postchallenge, birds were subjected to a transport stress procedure that included 12 h of holding time in a transport vehicle. The following morning all birds (n = 10 to 19 birds/line) were bled. Whole blood was analyzed using the Cell-Dyn 3500 blood analysis system (Abbott Diagnostics), and serum chemistry was measured using the Express Plus analyzer (Ciba-Corning Diagnostics Corp.). Transport significantly decreased the levels of hematocrit, hemoglobin, mean cell volume, mean corpuscular hemoglobin, glucose, triglycerides, cholesterol, phosphorus, iron, albumin, and alkaline phosphatase (AP) and increased the levels of uric acid, blood urea nitrogen, alanine aminotransferase, aspartate aminotransferase, and creatine kinase. Line differences were variable, but the levels of both iron and AP were least in the fastest-growing Comm line birds and greatest in the slowest-growing egg-line birds with intermediate values in the F line. Iron and AP were also the only parameters influenced by sex, with males having greater levels of both compared with females. The creatine kinase levels were more than 6-fold greater in transported Comm line birds, and iron levels of transported Comm males were 3-fold less than controls. Previously, the growth rate of these lines was positively correlated with increased heterophil to lymphocyte ratios and susceptibility to colibacillosis. The differences seen in the Comm line for these commonly measured blood parameters suggest that they may be useful for profiling flocks to determine their response to transport stress and feed withdrawal.

Mapping and discriminating the Pan-African granitoids in the Hoggar (southern Algeria) using Landsat 7 ETM+ data and airborne geophysics

NASA Astrophysics Data System (ADS)

Zerrouk, Siham; Bendaoud, Abderrahmane; Hamoudi, Mohamed; Liégeois, Jean Paul; Boubekri, Hichem; El Khaznadji, Riad Ben

2017-03-01

This study presents a multidisciplinary approach to discriminate and map different types and generations of Pan-African granitoids in the Hoggar, southern Algeria, using remote sensing and airborne geophysics in close correlation with previous works and established geological maps. RGB (Red, Green, Blue) combinations of band ratios; principal component analysis (PCA) and image classification for Landsat 7 ETM+ (Enhanced Thematic Mapper Plus), allow spatial discrimination and mapping of granitoid rocks of the studied area (200*350 km). This area extend over four contrasted Pan-African terranes (In Tedeini, Iskel, Tefedest and Laouni terranes, the two latter belong to the LATEA (Laouni-Azrou-n-Fad-Tefedest-Egéré-Aleksod-Assodé-Issalane) metacraton. The airborne magnetic intensity provides a wide range of responses from high values (youngest granitoids) to low values (volcano-sedimentary and gneissic country-rocks). Radiometric data, displaying radioelements concentration, discriminate efficiently the late alkaline granitoids (high values), the calk-alkaline granitoids (intermediate values) and the Tonalite-Trondhjemite-Granodiorite series (low values). This study led to the establishment of a more accurate geological map where the geochemical characteristics of the Pan-African granitoids are determined, including plutons not yet studied, especially in the poorly known In Tedeini terrane, and brings new constraints for the geodynamic development of the Tuareg Shield, which includes the Hoggar.

Synergetic effect of palladium-ruthenium nanostructures for ethanol electrooxidation in alkaline media

NASA Astrophysics Data System (ADS)

Monyoncho, Evans A.; Ntais, Spyridon; Soares, Felipo; Woo, Tom K.; Baranova, Elena A.

2015-08-01

Palladium-ruthenium nanoparticles supported on carbon PdxRu1-x/C (x = 1, 0.99, 0.95, 0.90, 0.80, 0.50) were prepared using a polyol method for ethanol electrooxidation in alkaline media. The resulting bimetallic catalysts were found to be primarily a mix of Pd metal, Ru oxides and Pd oxides. Their electrocatalytic activity towards ethanol oxidation reaction (EOR) in 1M KOH was studied using cyclic voltammetry and chronoamperometry techniques. Addition of 1-10 at.% Ru to Pd not only lowers the onset oxidation potential for EOR but also produces higher current densities at lower potentials compared to Pd by itself. Thus, Pd90Ru10/C and Pd99Ru1/C provide the current densities of up to six times those of Pd/C at -0.96 V and -0.67 V vs MSE, respectively. The current density at different potentials was found to be dependent on the surface composition of PdxRu1-x/C nanostructures. Pd90Ru10/C catalyst with more surface oxides was found to be active at lower potential compared to Pd99Ru1/C with less surface oxides, which is active at higher potentials. The steady-state current densities of the two best catalysts, Pd90Ru10/C and Pd99Ru1/C, showed minimal surface deactivation from EOR intermediates/products during chronoamperometry.

Purification and properties of an alkaline ribonuclease from the hepatic cytosol fraction of bullfrog, Rana catesbeiana.

PubMed

Nagano, H; Kiuchi, H; Abe, Y; Shukuya, R

1976-07-01

In the hepatic cytosol fraction of bullfrog, Rana catesbeiana, an alkaline RNase [EC 3.1.4.22] exists in two forms. One is the free form of RNase, which elutes from a carboxymethyl-cellulose column at a concentration of 0.2 M NaC1. The other is a masked or latent form (RNase-RNase inhibitor complex) which is not adsorbed on the carboxymethyl-cellulose column and which can be converted to the free form of RNase by the addition of p-chloromercuribenzoate. Electrophoretically pure RNase was obtained by the following procedure. The unadsorbed fraction of hepatic cytosol on a column of carboxymethyl-cellulose was treated with p-chloromercuribenzoate and then applied to a second carboxymethyl-cellulose column. The molar weight of RNase was determined to be approximately 12,000 by gel filtration and polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. From the results of gel filtration, the molecular weight of the RNase-RNase inhibitor complex was 130,000. The RNase hydrolyzed poly C, poly U, and poly I, but not poly A or poly G. When poly C was used as a substrate, 2',3'-cyclic CMP as an intermediate and 3'-CMP as a final product were identified. The results of amino acid analysis indicated the presence of an unusual component. The general properties of the RNase and the RNase-RNase inhibitor complex are also reported.

Characterizing the Effects of Inorganic Acid and Alkaline Shock on the Staphylococcus aureus Transcriptome and Messenger RNA Turnover

PubMed Central

Anderson, Kelsi L.; Roux, Christelle M.; Olson, Matthew W.; Luong, Thanh T.; Lee, Chia Y.; Olson, Robert; Dunman, Paul M.

2010-01-01

Staphylococcus aureus pathogenesis can be partially attributed to its ability to adapt to otherwise deleterious host-associated stresses. Here, Affymetrix GeneChips® were used to examine the S. aureus responses to inorganic acid and alkaline shock and to assess whether stress dependent changes in mRNA turnover are likely to facilitate the organism’s ability to tolerate pH challenge. Results indicate that S. aureus adapts to pH shock by eliciting responses expected of cells coping with pH alteration, including neutralizing cellular pH, DNA repair, amino acid biosynthesis and virulence factor expression. Further, the S. aureus response to alkaline conditions is strikingly similar to that of stringent response induced cells. Indeed, we show that alkaline shock stimulates accumulation of the stringent response activator (p)ppGpp. Results also revealed that pH shock significantly alters the mRNA properties of the cell. A comparison of the mRNA degradation properties of transcripts whose titers either increased or decreased in response to sudden pH change revealed that alterations in mRNA degradation may, in part, account for the changes in the mRNA levels of factors predicted to mediate pH tolerance. A set of small stable RNA molecules were induced in response to acid or alkaline shock conditions and may mediate adaptation to pH stress. PMID:21039920

Geochemical transformations and modeling of two deep-well injected hazardous wastes

USGS Publications Warehouse

Roy, W.R.; Seyler, B.; Steele, J.D.; Mravik, S.C.; Moore, D.M.; Krapac, I.G.; Peden, J.M.; Griffin, R.A.

1991-01-01

Two liquid hazardous wastes (an alkaline brine-like solution and a dilute acidic waste) were mixed with finely ground rock samples of three injection-related lithologies (sandstone, dolomite, and siltstone) for 155 to 230 days at 325??K-10.8 MPa. The pH and inorganic chemical composition of the alkaline waste were not significantly altered by any of the rock samples after 230 days of mixing. The acidic waste was neutralized as a consequence of carbonate dissolution, ion exchange, or clay-mineral dissolution, and hence was transformed into a nonhazardous waste. Mixing the alkaline waste with the solid phases yielded several reaction products: brucite, Mg(OH)2; calcite, CaCO3; and possibly a type of sodium metasilicate. Clay-like minerals formed in the sandstone, and hydrotalcite, Mg6Al2-CO3(OH)16??4H2O, may have formed in the siltstone at trace levels. Mixing the alkaline waste with a synthetic brine yielded brucite, calcite, and whewellite (CaC2O4??H2O). The thermodynamic model PHRQPITZ predicted that brucite and calcite would precipitate from solution in the dolomite and siltstone mixtures and in the alkaline waste-brine system. The dilute acidic waste did not significantly alter the mineralogical composition of the three rock types after 155 days of contact. The model PHREEQE indicated that the calcite was thermodynamically stable in the dolomite and siltstone mixtures.

Simulation of future stream alkalinity under changing deposition and climate scenarios.

PubMed

Welsch, Daniel L; Cosby, B Jack; Hornberger, George M

2006-08-31

Models of soil and stream water acidification have typically been applied under scenarios of changing acidic deposition, however, climate change is usually ignored. Soil air CO2 concentrations have potential to increase as climate warms and becomes wetter, thus affecting soil and stream water chemistry by initially increasing stream alkalinity at the expense of reducing base saturation levels on soil exchange sites. We simulate this change by applying a series of physically based coupled models capable of predicting soil air CO2 and stream water chemistry. We predict daily stream water alkalinity for a small catchment in the Virginia Blue Ridge for 60 years into the future given stochastically generated daily climate values. This is done for nine different combinations of climate and deposition. The scenarios for both climate and deposition include a static scenario, a scenario of gradual change, and a scenario of abrupt change. We find that stream water alkalinity continues to decline for all scenarios (average decrease of 14.4 microeq L-1) except where climate is gradually warming and becoming more moist (average increase of 13 microeq L-1). In all other scenarios, base cation removal from catchment soils is responsible for limited alkalinity increase resulting from climate change. This has implications given the extent that acidification models are used to establish policy and legislation concerning deposition and emissions.

Developing Computer-Interactive Tape Exercises for Intermediate-Level Business French.

ERIC Educational Resources Information Center

Garnett, Mary Anne

One college language teacher developed computer-interactive audiotape exercises for an intermediate-level class in business French. The project was undertaken because of a need for appropriate materials at that level. The use of authoring software permitted development of a variety of activity types, including multiple-choice, fill-in-the-blank,…

Final Environmental Planning Technical Report

DTIC Science & Technology

1984-01-01

or mildly alkaline (pH 7.3 to 7.8). Soils with a pH of less than 6.3 have been found to be too acidic for bone preservation (Hole and Heizer 1965...230; Heizer and Graham 1967:125). On the other hand, a pH of 6.0 has been said to be the highest level tolerated by pollen (Moore and Webb 1978:15...however, this cutoff point may be as high as 7.0 in arid or semiarid climates (Hole and Heizer 1965:282). The generally dry, neutral, or alkaline soil

Determining the degradation efficiency and mechanisms of ethyl violet using HPLC-PDA-ESI-MS and GC-MS

PubMed Central

2012-01-01

Background The discharge of wastewater that contains high concentrations of reactive dyes is a well-known problem associated with dyestuff activities. In recent years, semiconductor photocatalysis has become more and more attractive and important since it has a great potential to contribute to such environmental problems. One of the most important aspects of environmental photocatalysis is in the selection of semiconductor materials like ZnO and TiO2, which are close to being two of the ideal photocatalysts in several respects. For example, they are relatively inexpensive, and they provide photo-generated holes with high oxidizing power due to their wide band gap energy. In this work, nanostructural ZnO film on the Zn foil of the Alkaline-Manganese Dioxide-Zinc Cell was fabricated to degrade EV dye. The major innovation of this paper is to obtain the degradation mechanism of ethyl violet dyes resulting from the HPLC-PDA-ESI-MS analyses. Results The fabrication of ZnO nanostructures on zinc foils with a simple solution-based corrosion strategy and the synthesis, characterization, application, and implication of Zn would be reported in this study. Other objectives of this research are to identify the reaction intermediates and to understand the detailed degradation mechanism of EV dye, as model compound of triphenylmethane dye, with active Zn metal, by HPLC-ESI-MS and GC-MS. Conclusions ZnO nanostructure/Zn-foils had an excellent potential for future applications on the photocatalytic degradation of the organic dye in the environmental remediation. The intermediates of the degradation process were separated and characterized by the HPLC-PDA-ESI-MS and GC-MS, and twenty-six intermediates were characterized in this study. Based on the variation of the amount of intermediates, possible degradation pathways for the decolorization of dyes are also proposed and discussed. PMID:22748361

Paleozoic mafic-intermediate intrusions (320-287 Ma) in the Kalatongke area, southern Altai, NW China: Products of protracted magmatism in a convergent tectonic setting

NASA Astrophysics Data System (ADS)

Qian, Zhuangzhi; Duan, Jun; Li, Chusi; Xu, Gang; Feng, Yanqing; Ren, Meng

2018-06-01

Numerous small mafic-intermediate intrusions are present in the Kalatongke area in the southern part of the Paleozoic Altai Orogenic Belt, NW China. Previous studies reveal that most of these intrusions were emplaced at ∼287 Ma, broadly coeval with the eruption of alkaline flood basalts at ⩽282 Ma in the Tarim Craton. The similar ages have led some researchers to believe that the Tarim flood basalts and the Kalatongke mafic-intermediate intrusions are related to the same mantle plume. New and existing geochronological and geochemical data for the mafic-intermediate intrusions in the Kalatongke area together do not support such interpretation. Most of the intrusions in this small area (4.5 × 2 km) were emplaced at ∼287 Ma but our new data reveal that older intrusive rocks with zircon U-Pb ages from 290 ± 1.5 to 320 ± 2 Ma are also present. The temporal and spatial distribution of these intrusions does not show a hotspot track as expected by the mantle plume model. The intrusive rocks have similar Nd-Hf isotope compositions (εNd = 3-9, εHf = 15-19) and are all characterized by light REE enrichments relative to heavy REE, plus pronounced negative Nb-Ta anomalies. The oldest intrusion (∼320 Ma) also shows negative Zr-Hf anomalies, which are common in arc basalts but absent in continental flood basalts. The results of mixing calculations based on Sr-Nd-Hf isotopes and selected trace elements (Th, Nb and Yb) indicate that the parental magmas for these intrusions were all enriched in Th and depleted in Nb prior to crustal contamination, similar to the magmas generated in a convergent tectonic setting from subduction to post-subduction elsewhere in the world. The results from this study remind us that temporal correlation is not a reliable tool to determine the size of a mantle plume.

Investigations of Chemical and Biological Treatment Options for the Attenuation of Hexahydro-1,3,5-trinitro-1,3,5-triazine Contamination in Groundwater at Los Alamos, New Mexico

NASA Astrophysics Data System (ADS)

Heerspink, B. P.; Wang, D.; Ware, D.; Marina, O.; Perkins, G.; WoldeGabriel, G. W.; Goering, T.; Boukhalfa, H.

2017-12-01

High-explosive compounds including hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) were used extensively in weapons research and testing at Los Alamos National Laboratory (LANL) in Los Alamos, NM. Liquid effluents containing RDX released at LANL's Technical Area 16 (TA-16) resulted in the contamination of alluvial, perched-intermediate, and regional groundwater bodies. Past investigations have shown persistent RDX contamination in the perched-intermediate zone located between 225 to 311 m below ground surface, where transport studies have shown that RDX and its degradation products transport conservatively. In this study, we compared RDX degradation by chemical treatments using reduction by sodium dithionite, oxidation by potassium permanganate, and alkaline hydrolysis by carbonate/bicarbonate buffering, with microbial degradation under biostimulated conditions. The experiments were conducted using groundwater and sediments representative of the contaminated aquifer beneath TA-16. Batch testing showed that all chemical treatments degraded RDX very rapidly, with half-lives ranging from 50 minutes to 22 hours. Comparatively, RDX degradation in biostimulated reactors under strict anaerobic conditions was significantly slower, with half-lives of about 3 weeks. Results from column experiments with chemically treated sediments deviated from the results of the batch testing. Dithionite treated sediments reduced RDX with no breakthrough observed before clogging occurred at 50 pour volumes. Treatments by oxidation using potassium permanganate, and hydrolysis under buffered alkaline conditions, were less effective with complete RDX breakthrough after 2 pore volumes. No known degradation products were observed in the column effluents. RDX degradation in biostimulated columns was very effective initially for both treatments. However, the column biostimulated with safflower oil clogged very rapidly. The column biostimulated with molasses was very effective when molasses was continuously supplied but less effective after molasses injection stopped. Degradation products (hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine [MNX]; hexahydro-1,3-dinitro-5-nitro-1,3,5-triazine [DNX]; 2,4,6-trinitroxylene [TNX]) were visible in the effluents from the biostimulated columns.

Stacking and determination of phenazine-1-carboxylic acid with low pKa in soil via moving reaction boundary formed by alkaline and double acidic buffers in capillary electrophoresis.

PubMed

Sun, Chong; Yang, Xiao-Di; Fan, Liu-Yin; Zhang, Wei; Xu, Yu-Quan; Cao, Cheng-Xi

2011-04-01

As shown herein, a normal moving reaction boundary (MRB) formed by an alkaline buffer and a single acidic buffer had poor stacking to the new important plant growth promoter of phenazine-1-carboxylic acid (PCA) in soil due to the leak induced by its low pK(a). To stack the PCA with low pK(a) efficiently, a novel stacking system of MRB was developed, which was formed by an alkaline buffer and double acidic buffers (viz., acidic sample and blank buffers). With the novel system, the PCA leaking into the blank buffer from the sample buffer could be well stacked by the prolonged MRB formed between the alkaline buffer and blank buffer. The relevant mechanism of stacking was discussed briefly. The stacking system, coupled with sample pretreatment, could achieve a 214-fold increase of PCA sensitivity under the optimal conditions (15 mM (pH 11.5) Gly-NaOH as the alkaline buffer, 15 mM (pH 3.0) Gly-HCl-acetonitrile (20%, v/v) as the acidic sample buffer, 15 mM (pH 3.0) Gly-HCl as the blank buffer, 3 min 13 mbar injection of double acidic buffers, benzoic acid as the internal standard, 75 μm i.d. × 53 cm (44 cm effective length) capillary, 25 kV and 248 nm). The limit of detection of PCA in soil was decreased to 17 ng/g, the intra-day and inter-day precision values (expressed as relative standard deviations) were 3.17-4.24% and 4.17-4.87%, respectively, and the recoveries of PCA at three concentration levels changed from 52.20% to 102.61%. The developed method could be used for the detection of PCA in soil at trace level.

Zinc Extraction from Zinc Plants Residue Using Selective Alkaline Leaching and Electrowinning

NASA Astrophysics Data System (ADS)

Ashtari, Pedram; Pourghahramani, Parviz

2015-10-01

Annually, a great amount of zinc plants residue is produced in Iran. One of them is hot filter cake (known as HFC) which can be used as a secondary resource of zinc, cobalt and manganese. Unfortunately, despite its heavy metal content, the HFC is not treated. For the first time, zinc was selectively leached from HFC employing alkaline leaching. Secondly, leaching was optimized to achieve maximum recovery using this method. Effects of factors like NaOH concentration (C = 3, 5, 7 and 9 M), temperature (T = 50, 70, 90 and 105 °C), solid/liquid ratio (weight/volume, S/L = 1/10 and 1/5 W/V) and stirring speed (R = 500 and 800 rpm) were studied on HFC leaching. L16 orthogonal array (OA, two factors in four levels and two factors in two levels) was applied to determine the optimum condition and the most significant factor affecting the overall zinc extraction. As a result, maximum zinc extraction was 83.4 %. Afterwards, a rough test was conducted for zinc electrowinning from alkaline solution according to the common condition available in literature by which pure zinc powder (99.96 %) was successfully obtained.

Transcriptome Exploration in Leymus chinensis under Saline-Alkaline Treatment Using 454 Pyrosequencing

PubMed Central

Sun, Yepeng; Wang, Fawei; Wang, Nan; Dong, Yuanyuan; Liu, Qi; Zhao, Lei; Chen, Huan; Liu, Weican; Yin, Hailong; Zhang, Xiaomei; Yuan, Yanxi; Li, Haiyan

2013-01-01

Background Leymus chinensis (Trin.) Tzvel. is a high saline-alkaline tolerant forage grass genus of the tribe Gramineae family, which also plays an important role in protection of natural environment. To date, little is known about the saline-alkaline tolerance of L. chinensis on the molecular level. To better understand the molecular mechanism of saline-alkaline tolerance in L. chinensis, 454 pyrosequencing was used for the transcriptome study. Results We used Roche-454 massive parallel pyrosequencing technology to sequence two different cDNA libraries that were built from the two samples of control and under saline-alkaline treatment (optimal stress concentration-Hoagland solution with 100 mM NaCl and 200 mM NaHCO3). A total of 363,734 reads in control group and 526,267 reads in treatment group with an average length of 489 bp and 493 bp were obtained, respectively. The reads were assembled into 104,105 unigenes with MIRA sequence assemable software, among which, 73,665 unigenes were in control group, 88,016 unigenes in treatment group and 57,576 unigenes in both groups. According to the comparative expression analysis between the two groups with the threshold of “log2 Ratio ≥1”, there were 36,497 up-regulated unegenes and 18,218 down-regulated unigenes predicted to be the differentially expressed genes. After gene annotation and pathway enrichment analysis, most of them were involved in stress and tolerant function, signal transduction, energy production and conversion, and inorganic ion transport. Furthermore, 16 of these differentially expressed genes were selected for real-time PCR validation, and they were successfully confirmed with the results of 454 pyrosequencing. Conclusions This work is the first time to study the transcriptome of L. chinensis under saline-alkaline treatment based on the 454-FLX massively parallel DNA sequencing platform. It also deepened studies on molecular mechanisms of saline-alkaline in L. chinensis, and constituted a database for future studies. PMID:23365637

Assessment of stress in effect to pyrethroid insecticides, λ-cyhalothrin and cypermethrin, in a freshwater fish, Channa punctatus (BLOCH).

PubMed

Kumar, A; Sharma, B; Pandey, R S

2012-12-22

The present study was planned to see the changes in the levels of different biochemical stress markers such as the level of lipid peroxidation and the specific activities of lactate dehydrogenase (LDH), acid and alkaline phosphatases in different organs such as brain, liver, kidney, gills and muscle of a freshwater muddy fish, Channa punctatus in effect to pyrethroid insecticides, cypermethrin and λ-cyhalothrin treated for 96 h. The results showed significant increase in the levels of lipid peroxidation as well as the activities of LDH, acid and alkaline phosphatases in a dose dependent manner. The remarkable increase in the levels of these stress biomarkers indicates strong stress inducing potential of these insecticides in fishes. The importance of the current study lies in indicating the potential risk of muddy freshwater fishes due to strong soil binding property of pyrethroids along with their slow metabolism in fishes as compared to that of mammals.

The Hasan Dagi stratovolcano (Central Anatolia, Turkey): evolution from calc-alkaline to alkaline magmatism in a collision zone

NASA Astrophysics Data System (ADS)

Deniel, Catherine; Aydar, Erkan; Gourgaud, Alain

1998-12-01

The Hasan Dagi volcano is one of the two large Plio-Quaternary volcanoes in Cappadocia (Central Anatolia, Turkey). Three stages of edifice construction have been identified for this volcano: Paleovolcano, Mesovolcano and Neovolcano. Most samples from Hasan Dagi volcano are calc-alkaline and define an almost complete trend from basaltic andesite to rhyolite. However, the more recent (Neovolcano) mafic samples are alkaline basalts. The mineralogical and geochemical characteristics of the oldest lavas (Keçikalesi (13 Ma) and Paleo-Hasan Dagi (7 Ma)) are significantly different from those of the younger lavas (Meso- and Neo-Hasan Dagi (<1 Ma)). Calcic plagioclase and pigeonite are typically observed in these older lavas. The Paleovolcano basalts are depleted in alkalis and display a tholeiitic tendency whereas the differentiated lavas are depleted in Na 2O but enriched in K 2O compared to younger lavas. There is an evolution through time towards higher TiO 2, Fe 2O 3*, MgO, Na 2O and K 2O and lower Al 2O 3 and SiO 2 which is reflected in the basalt compositions. All the basalts display multi-element patterns typical of continental margin magmas with a significant enrichment in LILE (K, Rb, Ba and Th) and LREE and strong (Paleovolcano) to moderate (Meso- and Neovolcano) negative Nb, Zr and Ti anomalies. However, the younger basalts are the most enriched in incompatible elements, in agreement with their alkaline affinities and do not systematically display negative HFSE anomalies. REE data suggest an hydrous amphibole-bearing crystallization history for both Meso- and Neovolcano lavas. The distinction between the older and younger lavas is also apparent in trace element ratios such as Nb/Y, Ti/Y and Th/Y. These ratios indicate the role of a subducted component±crustal contamination in the genesis of the Hasan Dagi lavas, particularly for the oldest lavas (Keçikalesi and Paleo-Hasan Dagi). The decreasing influence of this component through time, over the last 6-7 m.y., has been accompanied by an increasing contribution of melt-enriched lithosphere. Although the range of variation of Sr, Nd and Pb isotopic ratios is small (0.70457-0.70515; 0.51262-0.51273; 18.80-18.94; 15.64-15.69; 38.87-39.10), it also reflects the evolution of the magma sources through time. Indeed, the youngest (Neovolcano) and most primitive basalts display significantly lower 87Sr/ 86Sr than the Paleo- and Mesovolcano basalts, whereas the Mesovolcano basalts display more radiogenic Pb than Paleovolcano samples. Magma mixing processes between initially heterogeneous and/or variably contaminated magmas may account for the genesis of the less differentiated and intermediate lavas (48-57% SiO 2). Meso- and Neovolcano differentiated lavas (60-68% SiO 2) are either derived from the analyzed basalts or from more primitive and more depleted magmas by fractional crystallization±some crustal contamination (AFC). Furthermore, the highly differentiated samples (72-75% SiO 2) are not strongly contaminated. The strong calc-alkaline character of Hasan Dagi lavas, in the absence of contemporaneous subduction, must reflect the heritage of the early subduction of the Afro-Arabian plate under the Eurasian plate. The evolution towards alkaline compositions through time is clearly related to the development of extensional tectonics in Central Anatolia in the Late Miocene.

Ontogeny and distribution of alkaline and acid phosphatases in the digestive system of California halibut larvae (Paralichthys californicus).

PubMed

Zacarias-Soto, Magali; Barón-Sevilla, Benjamín; Lazo, Juan P

2013-10-01

Studies aimed to assess the digestive physiology of marine fish larvae under culture conditions are important to further understand the functional characteristics and digestive capacities of the developing larvae. Most studies to date concentrate on intestinal lumen digestion and little attention to the absorption process. Thus, the objectives of this study were to histochemically detect and quantify some of the enzymes responsible for absorption and intracellular digestion of nutrients in the anterior and posterior intestine of California halibut larvae. Alkaline and acid phosphatases were detected from the first days post-hatch (dph). Alkaline phosphatase maintained a high level of activity during the first 20 dph in both intestinal regions. Thereafter, a clear intestinal regionalization of the activity was observed with the highest levels occurring in the anterior intestine. Acid phosphatase activity gradually increased in both intestinal regions during development, and a regionalization of the activity was not observed until late in development, once the ocular migration began. Highest levels were observed in the anterior intestine at the end of metamorphosis concomitant with the stomach development. The results from this study show some morphological and physiological changes are occurring during larval development and a clear regionalization of the absorption process as the larvae develops. These ontological changes must be considered in the elaboration of diets according to the digestive capacity of the larvae.

Anthropogenic CO2 in a dense water formation area of the Mediterranean Sea

NASA Astrophysics Data System (ADS)

Ingrosso, Gianmarco; Bensi, Manuel; Cardin, Vanessa; Giani, Michele

2017-05-01

There is growing evidence that the on-going ocean acidification of the Mediterranean Sea could be favoured by its active overturning circulation. The areas of dense water formation are, indeed, preferential sites for atmospheric carbon dioxide absorption and through them the ocean acidification process can quickly propagate into the deep layers. In this study we estimated the concentration of anthropogenic CO2 (Cant) in the dense water formation areas of the middle and southern Adriatic Sea. Using the composite tracer TrOCA (Tracer combining Oxygen, inorganic Carbon, and total Alkalinity) and carbonate chemistry data collected throughout March 2013, our results revealed that a massive amount of Cant has invaded all the identified water masses. High Cant concentration was detected at the bottom layer of the Pomo Pit (middle Adriatic, 96.8±9.7 μmol kg-1) and Southern Adriatic Pit (SAP, 85.2±9.4 μmol kg-1), associated respectively with the presence of North Adriatic Dense Water (NAdDW) and Adriatic Dense Water (AdDW). This anthropogenic contamination was clearly linked to the dense water formation events, which govern strong CO2 flux from the atmosphere to the sea and the sinking of dense, CO2-rich surface waters to the deep sea. However, a very high Cant level (94.5±12.5 μmol kg-1) was also estimated at the intermediate layer, as a consequence of a recent vertical mixing that determined the physical and biogeochemical modification of the water of Levantine origin (i.e. Modified Levantine Intermediate Water, MLIW) and favoured the atmospheric CO2 intrusion. The penetration of Cant in the Adriatic Sea determined a significant pH reduction since the pre-industrial era (- 0.139±0.019 pH units on average). This estimation was very similar to the global Mediterranean Sea acidification, but it was again more pronounced at the bottom of the Pomo Pit, within the layer occupied by NAdDW (- 0.157±0.018 pH units), and at the intermediate layer of the recently formed MLIW (- 0.143±0.020 pH units). Our results indicate that the Adriatic Sea could potentially be one of the Mediterranean regions most affected by the ocean acidification and also demonstrate its active role in sequestering and storing Cant.

Crystallization of oxidized, moderately hydrous arc basalt at mid- to lower-crustal pressures: implications for andesite genesis

NASA Astrophysics Data System (ADS)

Blatter, Dawnika L.; Sisson, Thomas W.; Hankins, W. Ben

2013-09-01

This study focuses on the production of convergent margin calc-alkaline andesites by crystallization-differentiation of basaltic magmas in the lower to middle crust. Previous experimental studies show that dry, reduced, subalkaline basalts differentiate to tholeiitic (high Fe/Mg) daughter liquids, but the influences of H2O and oxidation on differentiation are less well established. Accordingly, we performed crystallization experiments at controlled oxidized fO2 (Re-ReO2 ≈ ΔNi-NiO + 2) on a relatively magnesian basalt (8.7 wt% MgO) typical of mafic magmas erupted in the Cascades near Mount Rainier, Washington. The basalt was synthesized with 2 wt% H2O and run at 900, 700, and 400 MPa and 1,200 to 950 °C. A broadly clinopyroxenitic crystallization interval dominates near the liquidus at 900 and 700 MPa, consisting of augite + olivine + orthopyroxene + Cr-spinel (in decreasing abundance). With decreasing temperature, plagioclase crystallizes, Fe-Ti-oxide replaces spinel, olivine dissolves, and finally amphibole appears, producing gabbroic and then amphibole gabbroic crystallization stages. Enhanced plagioclase stability at lower pressure narrows the clinopyroxenitic interval and brings the gabbroic interval toward the liquidus. Liquids at 900 MPa track along Miyashiro's (Am J Sci 274(4):321-355, 1974) tholeiitic versus calc-alkaline boundary, whereas those at 700 and 400 MPa become calc-alkaline at silica contents ≥56 wt%. This difference is chiefly due to higher temperature appearance of magnetite (versus spinel) at lower pressures. Although the evolved liquids are similar in many respects to common calc-alkaline andesites, the 900 and 700 MPa liquids differ in having low CaO concentrations due to early and abundant crystallization of augite, with the result that those liquids become peraluminous (ASI: molar Al/(Na + K + 2Ca) > 1) at ≥61 wt% SiO2, similar to liquids reported in other studies of the high-pressure crystallization of hydrous basalts (Müntener and Ulmer in Geophys Res Lett 33(21):L21308, 2006). The lower-pressure liquids (400 MPa) have this same trait, but to a lesser extent due to more abundant near-liquidus plagioclase crystallization. A compilation of >6,500 analyses of igneous rocks from the Cascades and the Sierra Nevada batholith, representative of convergent margin (arc) magmas, shows that ASI increases continuously and linearly with SiO2 from basalts to rhyolites or granites and that arc magmas are not commonly peraluminous until SiO2 exceeds 69 wt%. These relations are consistent with plagioclase accompanying mafic silicates over nearly all the range of crystallization (or remelting). The scarcity of natural peraluminous andesites shows that progressive crystallization-differentiation of primitive basalts in the deep crust, producing early clinopyroxenitic cumulates and evolved liquids, does not dominate the creation of intermediate arc magmas or of the continental crust. Instead, mid- to upper-crustal differentiation and/or open-system processes are critical to the production of intermediate arc magmas. Primary among the open-system processes may be extraction of highly evolved (granitic, rhyolitic) liquids at advanced degrees of basalt solidification (or incipient partial melting of predecessor gabbroic intrusions) and mixing of such liquids into replenishing basalts. Furthermore, if the andesitic-composition continents derived from basaltic sources, the arc ASI-SiO2 relation shows that the mafic component returned to the mantle was gabbroic in composition, not pyroxenitic.

Crystallization of oxidized, moderately hydrous arc basalt at mid- to lower-crustal pressures: Implications for andesite genesis

USGS Publications Warehouse

Blatter, Dawnika L.; Sisson, Thomas W.; Hankins, W. Ben

2013-01-01

This study focuses on the production of convergent margin calc-alkaline andesites by crystallization–differentiation of basaltic magmas in the lower to middle crust. Previous experimental studies show that dry, reduced, subalkaline basalts differentiate to tholeiitic (high Fe/Mg) daughter liquids, but the influences of H2O and oxidation on differentiation are less well established. Accordingly, we performed crystallization experiments at controlled oxidized fO2 (Re–ReO2 ≈ ΔNi–NiO + 2) on a relatively magnesian basalt (8.7 wt% MgO) typical of mafic magmas erupted in the Cascades near Mount Rainier, Washington. The basalt was synthesized with 2 wt% H2O and run at 900, 700, and 400 MPa and 1,200 to 950 °C. A broadly clinopyroxenitic crystallization interval dominates near the liquidus at 900 and 700 MPa, consisting of augite + olivine + orthopyroxene + Cr-spinel (in decreasing abundance). With decreasing temperature, plagioclase crystallizes, Fe–Ti-oxide replaces spinel, olivine dissolves, and finally amphibole appears, producing gabbroic and then amphibole gabbroic crystallization stages. Enhanced plagioclase stability at lower pressure narrows the clinopyroxenitic interval and brings the gabbroic interval toward the liquidus. Liquids at 900 MPa track along Miyashiro’s (Am J Sci 274(4):321–355, 1974) tholeiitic versus calc-alkaline boundary, whereas those at 700 and 400 MPa become calc-alkaline at silica contents ≥56 wt%. This difference is chiefly due to higher temperature appearance of magnetite (versus spinel) at lower pressures. Although the evolved liquids are similar in many respects to common calc-alkaline andesites, the 900 and 700 MPa liquids differ in having low CaO concentrations due to early and abundant crystallization of augite, with the result that those liquids become peraluminous (ASI: molar Al/(Na + K + 2Ca) > 1) at ≥61 wt% SiO2, similar to liquids reported in other studies of the high-pressure crystallization of hydrous basalts (Müntener and Ulmer in Geophys Res Lett 33(21):L21308, 2006). The lower-pressure liquids (400 MPa) have this same trait, but to a lesser extent due to more abundant near-liquidus plagioclase crystallization. A compilation of >6,500 analyses of igneous rocks from the Cascades and the Sierra Nevada batholith, representative of convergent margin (arc) magmas, shows that ASI increases continuously and linearly with SiO2 from basalts to rhyolites or granites and that arc magmas are not commonly peraluminous until SiO2 exceeds 69 wt%. These relations are consistent with plagioclase accompanying mafic silicates over nearly all the range of crystallization (or remelting). The scarcity of natural peraluminous andesites shows that progressive crystallization–differentiation of primitive basalts in the deep crust, producing early clinopyroxenitic cumulates and evolved liquids, does not dominate the creation of intermediate arc magmas or of the continental crust. Instead, mid- to upper-crustal differentiation and/or open-system processes are critical to the production of intermediate arc magmas. Primary among the open-system processes may be extraction of highly evolved (granitic, rhyolitic) liquids at advanced degrees of basalt solidification (or incipient partial melting of predecessor gabbroic intrusions) and mixing of such liquids into replenishing basalts. Furthermore, if the andesitic-composition continents derived from basaltic sources, the arc ASI–SiO2 relation shows that the mafic component returned to the mantle was gabbroic in composition, not pyroxenitic.

Enzymatic production of xylooligosaccharides from corn stover and corn cobs treated with aqueous ammonia.

PubMed

Zhu, Yongming; Kim, Tae Hyun; Lee, Y Y; Chen, Rongfu; Elander, Richard T

2006-01-01

A novel method of producing food-grade xylooligosaccharides from corn stover and corn cobs was investigated. The process starts with pretreatment of feedstock in aqueous ammonia, which results delignified and xylan-rich substrate. The pretreated substrates are subjected to enzymatic hydrolysis of xylan using endoxylanase for production of xylooligosaccharides. The conventional enzyme-based method involves extraction of xylan with a strong alkaline solution to form a liquid intermediate containing soluble xylan. This intermediate is heavily contaminated with various extraneous components. A costly purification step is therefore required before enzymatic hydrolysis. In the present method, xylan is obtained in solid form after pretreatment. Water-washing is all that is required for enzymatic hydrolysis of this material. The complex step of purifying soluble xylan from contaminant is essentially eliminated. Refining of xylooligosaccharides to food-grade is accomplished by charcoal adsorption followed by ethanol elution. Xylanlytic hydrolysis of the pretreated corn stover yielded glucan-rich residue that is easily digestible by cellulase enzyme. The digestibility of the residue reached 86% with enzyme loading of 10 filter paper units/g-glucan. As a feedstock for xylooligosaccharides production, corn cobs are superior to corn stover because of high xylan content and high packing density. The high packing density of corn cobs reduces water input and eventually raises the product concentration.

Enhancement of the natural organic matter removal from drinking water by nanofiltration.

PubMed

Matilainen, A; Liikanen, R; Nyström, M; Lindqvist, N; Tuhkanen, T

2004-03-01

Finnish surface waters are abundant in natural organic matter. Natural organic matter can be removed from drinking water in a water treatment process by coagulation and filtration. The standard treatment operations are not able to remove the smallest molar mass fraction of organic matter and the intermediate molar mass matter is only partly removed. The removal of residual natural organic matter from drinking water by nanofiltration was evalueted in this study. Three different nanofiltration membranes were compared in filtering six pre-treated surface waters. The total organic carbon content of the feed waters varied from 2.0 to 4.2 mg l(-1). Other water quality parameters measured were conductivity, alkalinity, hardness, UV-absorbance, SUVA, E2/E3 value and molecular size distribution by high-performance size-exclusion chromatography. The natural organic matter removal efficiencies of the membranes were good and varied between 100% and 49%, and between 85% and 47% according to molecular size distribution and total organic carbon measurements, respectively. Removal of different molecular size fractions varied from 100% to 56%, 100% to 54% and 88% to 19%, regarding high molar mass, intermediate molar mass and low molar mass organic matter, respectively. The Desal-5 DL membrane produced the highest natural organic matter removals.

Water as a promoter and catalyst for dioxygen electrochemistry in aqueous and organic media.

DOE PAGES

Staszak-Jirkovsky, Jakub; Subbaraman, Ram; Strmcnik, Dusan; ...

2015-11-01

Water and oxygen electrochemistry lies at the heart of interfacial processes controlling energy transformations in fuel cells, electrolyzers, and batteries. Here, by comparing results for the ORR obtained in alkaline aqueous media to those obtained in ultradry organic electrolytes with known amounts of H2O added intentionally, we propose a new rationale in which water itself plays an important role in determining the reaction kinetics. This effect derives from the formation of HOad center dot center dot center dot H2O (aqueous solutions) and LiO2 center dot center dot center dot H2O (organic solvents) complexes that place water in a configurationally favorablemore » position for proton transfer to weakly adsorbed intermediates. We also find that, even at low concentrations (<10 ppm), water acts simultaneously as a promoter and as a catalyst in the production of Li2O2, regenerating itself through a sequence of steps that include the formation and recombination of H+ and OH-. We conclude that, although the binding energy between metal surfaces and oxygen intermediates is an important descriptor in electrocatalysis, understanding the role of water as a proton-donor reactant may explain many anomalous features in electrocatalysis at metal-liquid interfaces.« less

Abiotic vs biological sources and fates of organic compounds in a low temperature continental serpentinizing system

NASA Astrophysics Data System (ADS)

Robinson, K.; Noble, S. M.; Shock, E.

2016-12-01

Serpentinization is likely the most common water-rock reaction in our solar system. During this process ultramafic silicates are hydrated, a calcium hydroxide solution is formed, and H2O is reduced to H2 coupled to the oxidation of Fe2+ to Fe3+. The resulting hyper-alkaline, reduced conditions generate thermodynamic drives for numerous carbon compound reactions, including the precipitation of various carbonate minerals and the reduction of inorganic carbonate to organic carbon. Testing the extent to which these thermodynamic drives lead to observable results led to the present study of the flow and transformations of carbon through the active continental serpentinizing system at the Samail Ophiolite in the Sultanate of Oman. Water samples were collected from shallow groundwater (representing system input), hyper-alkaline seeps (system output), boreholes (system intermediate), and surface fluid mixing zones, and analyzed for concentrations of dissolved inorganic carbon (DIC + δ13C), organic carbon (+ δ13C), formate, acetate, H2, methane (+ δ13C), ethane, and an accompanying suite of other geochemical solutes. These analyses indicate that the vast majority of DIC in these serpentinizing fluids precipitates in the subsurface as carbonate minerals; however, a significant amount of DIC is converted into organic acids and light hydrocarbons and expelled at the surface in hyper-alkaline seeps. Based on thermodynamic calculations, it seems most likely that formate last equilibrated with dolomite (CaMg[CO3]2) in the subsurface, acetate last equilibrated with calcite (CaCO3) near the surface, and methane and ethane last equilibrated in a distinct carbon-limited region of the subsurface. As for the fates of these compounds, energetic calculations reveal that a combination of oxidative, reductive, and fermentative metabolisms are thermodynamically favorable. Indeed, δ13C trends record microbial methane oxidation at the surface and cannot rule out methane as biologically sourced from the subsurface.

Assessment of corticosteroid-induced alkaline phosphatase as a prognostic indicator in canine lymphoma.

PubMed

Wiedemann, A L; Charney, S C; Barger, A M; Schaeffer, D J; Kitchell, B E

2005-04-01

To examine the incidence of elevated corticosteroid-induced alkaline phosphatase (sALP) in dogs with lymphoma and to determine if sALP is a reliable prognostic indicator in canine lymphoma. The medical records of 62 canine lymphoma patients treated with a combination chemotherapy protocol from 1994 to 2003 at the University of Illinois Veterinary Teaching Hospital were examined. Variables assessed with respect to response rate and remission duration included age, bodyweight, sex, breed, World Health Organization stage (I to V), substage (a or b), pretreatment administration of corticosteroid, and serum levels of alkaline phosphatase, sALP and alanine aminotransferase. sALP was not statistically significant with respect to response rate or duration of remission, nor was preinduction glucocorticoid administration. Stage was significant with respect to achieving remission. It was found that sALP is not a useful prognostic indicator for response rate and remission duration in dogs with lymphoma.

Isolation and characterization of two immunochemically distinct alkaline phosphatases from Pseudomonas aeruginosa.

PubMed

Tan, A S; Worobec, E A

1993-02-01

We have isolated two alkaline phosphatases (H-AP and L-AP, for high and low molecular mass, respectively) from Pseudomonas aeruginosa PA01. These two enzymes were found to differ in mobility on sodium dodecyl sulphate polyacrylamide gels (H-AP, M(r) = 51,000 and L-AP, M(r) = 39,500), amino-terminal amino acid sequence and did not cross-react. Both enzymes were active as phosphomonoesterases while only L-AP demonstrated any phosphodiesterase activity. Both enzymes were purified from P. aeruginosa grown in phosphate limiting conditions using the same protocol and were identified in both periplasmic and extracellular locations. A low level of H-AP was produced constitutively whereas L-AP was produced only after induction by reduced phosphate concentration in the growth medium. An L-AP-like enzyme has been previously described, however, this is the first report of a second P. aeruginosa alkaline phosphatase.

Membrane topology analysis of Escherichia coli K-12 Mtr permease by alkaline phosphatase and beta-galactosidase fusions.

PubMed

Sarsero, J P; Pittard, A J

1995-01-01

The mtr gene of Escherichia coli K-12 encodes an inner membrane protein which is responsible for the active transport of trypotophan into the cell. It has been proposed that the Mtr permease has a novel structure consisting of 11 hydrophobic transmembrane spans, with a cytoplasmically disposed amino terminus and a carboxyl terminus located in the periplasmic space (J.P. Sarsero, P. J. Wookey, P. Gollnick, C. Yanofsky, and A.J. Pittard, J. Bacteriol. 173:3231-3234, 1991). The validity of this model was examined by the construction of fusion proteins between the Mtr permease and alkaline phosphatase or beta-galactosidase. In addition to the conventional methods, in which the reporter enzyme replaces a carboxyl-terminal portion of the membrane protein, the recently developed alkaline phosphatase sandwich fusion technique was utilized, in which alkaline phosphatase is inserted into an otherwise intact membrane protein. A cluster of alkaline phosphatase fusions to the carboxyl-terminal end of the Mtr permease exhibited high levels of alkaline phosphatase activity, giving support to the proposition of a periplasmically located carboxyl terminus. The majority of fusion proteins produced enzymatic activities which were in agreement with the positions of the fusion sites on the proposed topological model of the permease. The synthesis of a small cluster of hybrid proteins, whose enzymatic activity did not agree with the location of their fusion sites within putative transmembrane span VIII or the preceding periplasmic loop, was not detected by immunological techniques and did not necessitate modification of the proposed model in this region. Slight alterations may need to be made in the positioning of the carboxyl-terminal end of transmembrane span X.

Catalytically active alkaline molten globular enzyme: Effect of pH and temperature on the structural integrity of 5-aminolevulinate synthase*

PubMed Central

Stojanovski, Bosko M.; Breydo, Leonid; Hunter, Gregory A.; Uversky, Vladimir N.; Ferreira, Gloria C.

2014-01-01

5-Aminolevulinate synthase (ALAS), a pyridoxal-5′phosphate (PLP)-dependent enzyme, catalyzes the first step of heme biosynthesis in mammals. Circular dichroism (CD) and fluorescence spectroscopies were used to examine the effects of pH (1.0–3.0 and 7.5–10.5) and temperature (20 and 37 °C) on the structural integrity of ALAS. The secondary structure, as deduced from far-UV CD, is mostly resilient to pH and temperature changes. Partial unfolding was observed at pH 2.0, but further decreasing pH resulted in acid-induced refolding of the secondary structure to nearly native levels. The tertiary structure rigidity, monitored by near-UV CD, is lost under acidic and specific alkaline conditions (pH 10.5 and pH 9.5/37 °C), where ALAS populates a molten globule state. As the enzyme becomes less structured with increased alkalinity, the chiral environment of the internal aldimine is also modified, with a shift from a 420 nm to 330 nm dichroic band. Under acidic conditions, the PLP cofactor dissociates from ALAS. Reaction with 8-anilino-1-naphtalenesulfonic acid corroborates increased exposure of hydrophobic clusters in the alkaline and acidic molten globules, although the reaction is more pronounced with the latter. Furthermore, quenching the intrinsic fluorescence of ALAS with acrylamide at pH 1.0 and 9.5 yielded subtly different dynamic quenching constants. The alkaline molten globule state of ALAS is catalytically active (pH 9.5/37 °C), although the kcat value is significantly decreased. Finally, the binding of 5-aminolevulinate restricts conformational fluctuations in the alkaline molten globule. Overall, our findings prove how the structural plasticity of ALAS contributes to reaching a functional enzyme. PMID:25240868

Comparative evaluation of acid and alkaline sulfite pretreatments for enzymatic saccharification of bagasses from three different sugarcane hybrids.

PubMed

Monte, Joseana R; Laurito-Friend, Debora F; Ferraz, André; Milagres, Adriane M F

2018-04-26

Sugarcane bagasses from three experimental sugarcane hybrids and a mill-reference sample were used to compare the efficiency and mode of action of acid and alkaline sulfite pretreatment processes. Varied chemical loads and reaction temperatures were used to prepare samples with distinguished characteristics regarding xylan and lignin removals, as well as sulfonation levels of residual lignins. The pretreatment with low sulfite loads (5%) under acidic conditions (pH 2) provided maximum glucose yield of 70% during enzymatic hydrolysis with cellulases (10 FPU/g) and β-glucosidases (20 UI/g bagasse). In this case, glucan enzymatic conversion from pretreated materials was mostly associated with extensive xylan removal (70-100%) and partial delignification occurred during the pretreatment. The use of low sulfite loads under acidic conditions required pretreatment temperatures of 160°C. In contrast, at a lower pretreatment temperature (120°C), alkaline sulfite process achieved similar glucan digestibility, but required a higher sulfite load (7.5%). Residual xylans from acid pretreated materials were almost completely hydrolysed by commercial enzymes, contrasting with relatively lower xylan to xylose conversions observed in alkaline pretreated samples. Efficient xylan removal during acid sulfite pretreatment and also during enzymatic digestion can be useful to enhance glucan accessibility and digestibility by cellulases. Alkaline sulfite process also provided substrates with high glucan digestibility, mainly associated with delignification and sulfonation of residual lignins. The results demonstrate that temperature, pH and sulfite can be combined for reducing lignocellulose recalcitrance and achieve similar glucan conversion rates in the alkaline and acid sulfite pretreated bagasses. This article is protected by copyright. All rights reserved. © 2018 American Institute of Chemical Engineers.

Gymnocypris przewalskii decreases cytosolic carbonic anhydrase expression to compensate for respiratory alkalosis and osmoregulation in the saline-alkaline lake Qinghai.

PubMed

Yao, Zongli; Guo, Wenfei; Lai, Qifang; Shi, Jianquan; Zhou, Kai; Qi, Hongfang; Lin, Tingting; Li, Ziniu; Wang, Hui

2016-01-01

Naked carp (Gymnocypris przewalskii), endemic to the saline-alkaline Lake Qinghai, have the capacity to tolerate combined high salinity and alkalinity, but migrate to spawn in freshwater rivers each year. In this study, the full-length cDNA of the cytosolic carbonic anhydrase c isoform of G. przewalskii (GpCAc) was amplified and sequenced; mRNA levels and enzyme activity of GpCAc and blood chemistry were evaluated to understand the compensatory responses as the naked carp returned to the saline-alkaline lake after spawning. We found that GpCAc had a total length of 1400 bp and encodes a peptide of 260 amino acids. Comparison of the deduced amino acid sequences and phylogenetic analysis showed that GpCAc was a member of the cytosolic carbonic anhydrase II-like c family. Cytosolic-carbonic-anhydrase-c-specific primers were used to analyze the tissue distribution of GpCAc mRNA expression. Expression of GpCAc mRNA was found in brain, gill, liver, kidney, gut, and muscle tissues, but primarily in the gill and posterior kidney; however, none was evident in red blood cells. Transferring fish from river water to lake water resulted in a respiratory alkalosis, osmolality, and ion rise in the blood, as well as significant decreases in the expression and enzyme activity of GpCAc in both the gill and kidney within 96 h. These results indicate that GpCAc may play an important role in the acclimation to both high salinity and carbonate alkalinity. Specifically, G. przewalskii decreases cytosolic carbonic anhydrase c expression to compensate for a respiratory alkalosis and to aid in osmoregulation during the transition from river to saline-alkaline lake.

pH modulation ameliorates the red blood cell storage lesion in a murine model of transfusion.

PubMed

Chang, Alex L; Kim, Young; Seitz, Aaron P; Schuster, Rebecca M; Pritts, Timothy A

2017-05-15

Prolonged storage of packed red blood cells (pRBCs) induces a series of harmful biochemical and metabolic changes known as the RBC storage lesion. RBCs are currently stored in an acidic storage solution, but the effect of pH on the RBC storage lesion is unknown. We investigated the effect of modulation of storage pH on the RBC storage lesion and on erythrocyte survival after transfusion. Murine pRBCs were stored in Additive Solution-3 (AS3) under standard conditions (pH, 5.8), acidic AS3 (pH, 4.5), or alkalinized AS3 (pH, 8.5). pRBC units were analyzed at the end of the storage period. Several components of the storage lesion were measured, including cell-free hemoglobin, microparticle production, phosphatidylserine externalization, lactate accumulation, and byproducts of lipid peroxidation. Carboxyfluorescein-labeled erythrocytes were transfused into healthy mice to determine cell survival. Compared with pRBCs stored in standard AS3, those stored in alkaline solution exhibited decreased hemolysis, phosphatidylserine externalization, microparticle production, and lipid peroxidation. Lactate levels were greater after storage in alkaline conditions, suggesting that these pRBCs remained more metabolically viable. Storage in acidic AS3 accelerated erythrocyte deterioration. Compared with standard AS3 storage, circulating half-life of cells was increased by alkaline storage but decreased in acidic conditions. Storage pH significantly affects the quality of stored RBCs and cell survival after transfusion. Current erythrocyte storage solutions may benefit from refinements in pH levels. Copyright © 2016 Elsevier Inc. All rights reserved.

An intermediate level of BMP signaling directly specifies cranial neural crest progenitor cells in zebrafish.

PubMed

Schumacher, Jennifer A; Hashiguchi, Megumi; Nguyen, Vu H; Mullins, Mary C

2011-01-01

The specification of the neural crest progenitor cell (NCPC) population in the early vertebrate embryo requires an elaborate network of signaling pathways, one of which is the Bone Morphogenetic Protein (BMP) pathway. Based on alterations in neural crest gene expression in zebrafish BMP pathway component mutants, we previously proposed a model in which the gastrula BMP morphogen gradient establishes an intermediate level of BMP activity establishing the future NCPC domain. Here, we tested this model and show that an intermediate level of BMP signaling acts directly to specify the NCPC. We quantified the effects of reducing BMP signaling on the number of neural crest cells and show that neural crest cells are significantly increased when BMP signaling is reduced and that this increase is not due to an increase in cell proliferation. In contrast, when BMP signaling is eliminated, NCPC fail to be specified. We modulated BMP signaling levels in BMP pathway mutants with expanded or no NCPCs to demonstrate that an intermediate level of BMP signaling specifies the NCPC. We further investigated the ability of Smad5 to act in a graded fashion by injecting smad5 antisense morpholinos and show that increasing doses first expand the NCPCs and then cause a loss of NCPCs, consistent with Smad5 acting directly in neural crest progenitor specification. Using Western blot analysis, we show that P-Smad5 levels are dose-dependently reduced in smad5 morphants, consistent with an intermediate level of BMP signaling acting through Smad5 to specify the neural crest progenitors. Finally, we performed chimeric analysis to demonstrate for the first time that BMP signal reception is required directly by NCPCs for their specification. Together these results add substantial evidence to a model in which graded BMP signaling acts as a morphogen to pattern the ectoderm, with an intermediate level acting in neural crest specification.

Quantitative PCR estimates Angiostrongylus cantonensis (rat lungworm) infection levels in semi-slugs (Parmarion martensi)

PubMed Central

Jarvi, Susan I.; Farias, Margaret E.M.; Howe, Kay; Jacquier, Steven; Hollingsworth, Robert; Pitt, William

2013-01-01

The life cycle of the nematode Angiostrongylus cantonensis involves rats as the definitive host and slugs and snails as intermediate hosts. Humans can become infected upon ingestion of intermediate or paratenic (passive carrier) hosts containing stage L3 A. cantonensis larvae. Here, we report a quantitative PCR (qPCR) assay that provides a reliable, relative measure of parasite load in intermediate hosts. Quantification of the levels of infection of intermediate hosts is critical for determining A. cantonensis intensity on the Island of Hawaii. The identification of high intensity infection ‘hotspots’ will allow for more effective targeted rat and slug control measures. qPCR appears more efficient and sensitive than microscopy and provides a new tool for quantification of larvae from intermediate hosts, and potentially from other sources as well. PMID:22902292

Endurance test and evaluation of alkaline water electrolysis cells

NASA Technical Reports Server (NTRS)

Burke, K. A.; Schubert, F. H.

1981-01-01

Utilization in the development of multi-kW low orbit power systems is discussed. The following technological developments of alkaline water electrolysis cells for space power application were demonstrated: (1) four 92.9 cm2 single water electrolysis cells, two using LST's advanced anodes and two using LST's super anodes; (2) four single cell endurance test stands for life testing of alkaline water electrolyte cells; (3) the solid performance of the advanced electrode and 355 K; (4) the breakthrough performance of the super electrode; (5) the four single cells for over 5,000 hours each significant cell deterioration or cell failure. It is concluded that the static feed water electrolysis concept is reliable and due to the inherent simplicity of the passive water feed mechanism coupled with the use of alkaline electrolyte has greater potential for regenerative fuel cell system applications than alternative electrolyzers. A rise in cell voltage occur after 2,000-3,000 hours which was attributed to deflection of the polysulfone end plates due to creepage of the thermoplastic. More end plate support was added, and the performance of the cells was restored to the initial performance level.

Exogenous Melatonin Alleviates Alkaline Stress in Malus hupehensis Rehd. by Regulating the Biosynthesis of Polyamines.

PubMed

Gong, Xiaoqing; Shi, Shuting; Dou, Fangfang; Song, Yi; Ma, Fengwang

2017-09-13

Since melatonin was identified in plants decades ago, much attention has been devoted to discovering its role in plant science. There is still a great deal to learn about the functional importance of melatonin, as well as its functional mode. In this paper, we examine the role of melatonin treatment in the response of Malus hupehensis Rehd. to alkaline conditions. Stressed seedlings showed chlorosis and suppressed growth. However, this phenotype was ameliorated when 5 µM melatonin was added to the irrigation solution. This supplementation was also associated with a reduction in cell membrane damage and maintenance of a normal root system architecture. Fewer reactive oxygen species (ROS) were accumulated due to the enhanced scavenging activity of antioxidant enzymes superoxide dismutase, peroxidase, and catalase. In addition, alkaline-stressed seedlings that received the melatonin supplement accumulated more polyamines compared with untreated seedlings. Transcript levels of six genes involved in polyamine synthesis, including SAMDC1 , - 3 , and - 4 , and SPDS1 , - 3 , and - 5 , - 6 , were upregulated in response to melatonin application. All of these results demonstrate that melatonin has a positive function in plant tolerance to alkaline stress because it regulates enzyme activity and the biosynthesis of polyamines.

Bacterial treatment of alkaline cement kiln dust using Bacillus halodurans strain KG1.

PubMed

Kunal; Rajor, Anita; Siddique, Rafat

2016-01-01

This study was conducted to isolate an acid-producing, alkaliphilic bacterium to reduce the alkalinity of cement industry waste (cement kiln dust). Gram-positive isolate KG1 grew well at pH values of 6-12, temperatures of 28-50°C, and NaCl concentrations of 0-16% and thus was further screened for its potential to reduce the pH of an alkaline medium. Phenotypic characteristics of the KG1 isolate were consistent with those of the genus Bacillus, and the highest level of 16S rRNA gene sequence similarity was found with Bacillus halodurans strain DSM 497 (94.7%). On the basis of its phenotypic characteristics and genotypic distinctiveness from other phylogenetic neighbors belonging to alkaliphilic Bacillus species, the isolated strain was designated B. halodurans strain KG1, with GenBank accession number JQ307184 (= NCIM 5439). Isolate KG1 reduced the alkalinity (by 83.64%) and the chloride content (by 86.96%) of cement kiln dust and showed a potential to be used in the cement industry for a variety of applications. Copyright © 2015 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

Energetics of alkali and alkaline earth ion-exchanged zeolite A

DOE PAGES

Sun, Hui; Wu, Di; Liu, Kefeng; ...

2016-06-30

Alkali and alkaline earth ion-exchanged zeolite A samples were synthesized in aqueous exchange media. They were thoroughly studied by powder X-ray diffraction (XRD), electron microprobe (EMPA), thermogravimetric analysis and differential scanning calorimetry (TG-DSC), and high temperature oxide melt solution calorimetry. The hydration energetics and enthalpies of formation of these zeolite A materials from constituent oxides were determined. Specifically, the hydration level of zeolite A has a linear dependence on the average ionic potential ( Z/r) of the cation, from 0.894 (Rb-A) to 1.317 per TO 2 (Mg-A). The formation enthalpies from oxides (25 °C) range from –93.71 ± 1.77 (K-A)more » to –48.02 ± 1.85 kJ/mol per TO 2 (Li-A) for hydrated alkali ion-exchanged zeolite A, and from –47.99 ± 1.20 (Ba-A) to –26.41 ± 1.71 kJ/mol per TO 2 (Mg-A) for hydrated alkaline earth ion-exchanged zeolite A. As a result, the formation enthalpy from oxides generally becomes less exothermic as Z/r increases, but a distinct difference in slope is observed between the alkali and the alkaline earth series.« less

Hydroxide as general base in the saponification of ethyl acetate.

PubMed

Mata-Segreda, Julio F

2002-03-13

The second-order rate constant for the saponification of ethyl acetate at 30.0 degrees C in H(2)O/D(2)O mixtures of deuterium atom fraction n (a proton inventory experiment) obeys the relation k(2)(n) = 0.122 s(-1) M(-1) (1 - n + 1.2n) (1 - n + 0.48n)/(1 - n + 1.4n) (1 - n + 0.68n)(3). This result is interpreted as a process where formation of the tetrahedral intermediate is the rate-determining step and the transition-state complex is formed via nucleophilic interaction of a water molecule with general-base assistance from hydroxide ion, opposite to the direct nucleophilic collision commonly accepted. This mechanistic picture agrees with previous heavy-atom kinetic isotope effect data of Marlier on the alkaline hydrolysis of methyl formate.

Co-existing calcic amphiboles in calc-alkaline andesites: Possible evidence of a zoned magma chamber

NASA Astrophysics Data System (ADS)

Green, Nathan L.

1982-03-01

Hornblende-biotite andesites erupted from Mount Price and Clinker Peak volcanoes, southwestern British Columbia, contain two texturally and compositionally distinct calcic amphiboles: pargasitic hornblende xenocrysts and magnesio-hornblende microphenocrysts. Disequilibrium relationships exhibited by these amphiboles and associated minerals suggest that the magnesio-hornblendes precipitated under chemical and thermal conditions that were intermediate between those under which pargasitic hornblende and biotite, respectively, crystallized. Experimental studies of crystallization in double-diffusive systems (Chen and Turner, 1980; Turner, 1980; McBirney, 1980) suggest that these varied magmatic environments can be explained as a consequence of progressive crystallization within a zoned magma chamber. Although gravitational settling may have played a role, the observed mineral assemblages probably developed by convective mixing of crystals precipitated at the cooling margins with those crystallized in the interior of the compositionally stratified magma column.

D-Galacturonic acid as a highly reactive compound in nonenzymatic browning. 1. Formation of browning active degradation products.

PubMed

Bornik, Maria-Anna; Kroh, Lothar W

2013-04-10

Thermal treatment of an aqueous solution of D-galacturonic acid at pH 3, 5, and 8 led to rapid browning of the solution and to the formation of carbocyclic compounds such as reductic acid (2,3-dihydroxy-2-cyclopenten-1-one), DHCP (4,5-dihydroxy-2-cyclopenten-1-one), and furan-2-carbaldehyde, as degradation products in weak acidic solution. Studies on their formation revealed 2-ketoglutaraldehyde as their common key intermediate. Norfuraneol (4-hydroxy-5-methyl-3-(2H)-furanone) is a typical alkaline degradation product and formed after isomerization. Further model studies revealed reductic acid as an important and more browning active compound than furan-2-carbaldehyde, which led to a red color of the model solution. This red-brown color is also characteristic of thermally treated uronic acid solutions.

Incoherence in the South African Labour Market for Intermediate Skills

ERIC Educational Resources Information Center

Kraak, Andre

2008-01-01

This article is concerned with the production and employment of technically skilled labour at the intermediate level in South Africa. Three differing labour market pathways to intermediate skilling are identified. These are: the traditional apprenticeship route, the new "Learnerships" pathway (similar to the "modern…

The effects of subcutaneous injection of nicotine on osseointegration of machined and anodized implants in rabbits.

PubMed

Linden, Maria Salete Sandini; Bittencourt, Marcos Eugênio de; Carli, João Paulo De; Miyagaki, Daniela Cristina; Santos, Pâmela Letícia Dos; Paranhos, Luiz Renato; Groppo, Francisco Carlos; Ramacciato, Juliana Cama

2018-01-01

To evaluate the influence of subcutaneous injection nicotine in osseointegration process on different implant surfaces. Twenty-two male rabbits were distributed into two groups according to the subcutaneous injections: (1) nicotine 3 mg/day/kg and (2) 0.9 % NaCI 3 mL/day/kg, three times a day; subgroups were then designated-machined and anodized implants were placed in the right and left tibia bones, respectively. The animals were submitted euthanasia after periods of eight weeks to determine nicotine and cotinine levels, alkaline phosphatase and biomechanical analysis. The plasmatic levels of nicotine and cotinine were 0.5 ± 0.28 ng/mL and 9.5 ± 6.51 ng/mL, respectively. The alkaline phosphatase analyses in blood levels in control group were observed 40.8 ± 11.88 UI/L and 40.75 ± 12.46 UI/L, for the surfaces machined and anodized, respectively. In the test group was observed levels 37.9 ± 4.84 UI/L, for both implant surfaces. No significant differences were observed between control and test groups and between the implant surfaces regarding alkaline phosphatase blood levels. For biomechanics, no significant differences were observed in control group between the machined (25±8.46 Ncm) or anodized (31.2 ± 6.76 Ncm) implants. However, the treatment with nicotine induced higher torque than control in both machined (38.3 ± 13.52 Ncm) and anodized (35.5 ± 14.17 Ncm) implants, with p = 0.0024 and p = 0.0121, respectively. Subcutaneous injection of nicotine following implant insertion didn't have effect on osseointegration, independently from the implant surface.

SPACE: Intermediate Level Modules.

ERIC Educational Resources Information Center

Indiana State Dept. of Education, Indianapolis. Center for School Improvement and Performance.

These modules were developed to assist teachers at the intermediate level to move away from extensive skill practice and toward more meaningful interdisciplinary learning. This packet, to be used by teachers in the summer Extended Learning Program, provides detailed thematic lesson plans matched to the Indiana Curriculum Proficiency Guide. The…

Connecting Language to Content: Second Language Literature Instruction at the Intermediate Level

ERIC Educational Resources Information Center

Hoecherl-Alden, Gisela

2006-01-01

Meaningfully integrating multidimensional approaches with learner-centered, workshop-style second language (L2) literature instruction at intermediate-level proficiency can help students increase their linguistic competence and further both their cultural understanding and analytical thinking skills. Moreover, the utilization of drama techniques…

Potentiometric surface of the intermediate aquifer system, west- central Florida, May 1987

USGS Publications Warehouse

Lewelling, B.R.

1988-01-01

The intermediate aquifer system within the Southwest Florida Water Management District underlies a 5,000 sq mi area of De Soto, Sarasota, Hardee, Manatee, and parts of Charlotte, Hillsborough, Highlands, and Polk Counties. The intermediate aquifer system occurs between the overlying surficial aquifer system and the underlying Floridan aquifer system, and consists of layers of sand, shell, clay, marl, limestone, and dolom of the Tamiami, Hawthorn, and Tampa Formations of late Tertiary age. The intermediate aquifer system contains one or more water-bearing units separated by discontinuous confining units. This aquifer system is the principal source of potable water in the southwestern part of the study area and is widely used as a source of water in other parts where wells are open to the intermediate aquifer system or to both the intermediate and Floridan aquifer systems. Yields of individual wells open to the intermediate aquifer system range from a few gallons to several hundred gallons per minute. The volume of water withdrawn from the intermediate aquifer system is considerably less than that withdrawn from the Floridan aquifer system in the study area. The surface was mapped by determining the altitude of water levels in a network of wells and is represented on maps by contours that connect points of equal altitude. The compos potentiometric surface of all water-bearing units within the intermediate aquifer system is shown. In areas where multiple aquifers exist, wells open to all aquifers were selected for water level measurements whenever possible. In the southwestern and lower coastal region of the study area, two aquifers and confining units are described for the intermediate aquifer system: the Tamiami-upper Hawthorn aquifer and the underlying lower Hawthorn-upper Tampa aquifer. The potentiometric surface of the Tamiami-upper Hawthorn aquifer is also shown. Water levels are from wells drilled and open exclusively to that aquifer. The exact boundary for the Tamiami-upper Hawthorn aquifer is undetermined because of limd geohydrologic data available from wells. (Lantz-PTT)

Genome-wide identification of genes involved in polyamine biosynthesis and the role of exogenous polyamines in Malus hupehensis Rehd. under alkaline stress.

PubMed

Gong, Xiaoqing; Dou, Fangfang; Cheng, Xi; Zhou, Jing; Zou, Yangjun; Ma, Fengwang

2018-08-30

Polyamines (PAs) in plants are growth substrates with functions similar to phytohormones. Although they contribute to diverse processes, little is known about their role in stress responses, especially for perennial woody plants. We conducted a genome-wide investigation of 18 sequences involved in PA biosynthesis in the genome of apple (Malus domestica). Further analysis was performed to construct a phylogenetic tree, analyze their protein motifs and gene structures. In addition, we developed their expression profiles in response to stressed conditions. Both MDP0000171041 (MdSAMDC1) and MDP0000198590 (MdSPDS1) were induced by alkaline, salt, ABA, cold, and dehydration stress treatments, suggesting that these genes are the main contributors to activities of S-adenosylmethionine decarboxylase (EC 4.1.1.50) and spermidine synthase (EC 2.5.1.16) in apple. Changes in PA biosynthesis under stress conditions indicated that spermidine and spermine are more essential than putrescine for apple, especially when responding to alkaline or salt stress. When seedlings of M. hupehensis Rehd. were supplied with exogenous PAs, their leaves showed less chlorosis under alkaline stress when compared with untreated plants. This application also inhibited the decline in SPAD levels and reduced relative electrolyte leakage in those stressed seedlings, while increasing their concentration of active iron. These results suggest that the alteration in PA biosynthesis confers enhanced tolerance to alkaline stress in M. hupehensis Rehd. Copyright © 2018. Published by Elsevier B.V.

[Intraoperative lactic acidosis, can it be treated? Clinico-experimental, prospective, sequential study].

PubMed

Pietropaoli, P; Caporelli, S; De Pace, F; Donati, A; Adrario, E; Luzi, A; Munch, C; Giovannini, C; Frezzotti, A R

1994-12-01

To verify the efficacy and absence of risk attributable to therapy with alkaline solutions for correction of lactic acidosis and to demonstrate the usefulness of L-carnitine in converting lactate into pyruvate in conditions of good blood oxygenation. Prospective study on a consecutive series of patients subdivided into three groups following the use of: alkalinizing therapy (group I), L-carnitine (group II), or saline solution (group III). Groups 1 and 2 were further subdivided into subgroups "a" and "b" according to the type of alkalinizing agent and of L-carnitine somministration. Teaching Hospital-Torrette di Ancona. 65 patients submitted to major vascular surgery with aortic clamping in the time period between January 1992 and August 1993. During aortic clamping patients of: group I received 2 mEq:kg of bicarbonate or tromentamolo according to the specific subgroup. Group II received a bolus of 2 g of L-carnitine, patients of group IIb received further 2 g of carnitine in continuous perfusion until the end of surgery. Group III received no pharmacological intervention. HR BP, arterial blood gases and lactic acid levels were measured at 12 pre-determined times. Only a neutralizing effect of alkalinizing therapy was observed, whereas the lactic acid measurements demonstrated no significant differences between the different groups. These results confirm the data of other Authors concerning the good compliance of alkalinizing therapy, however, there was demonstrated no clear evidence of its effective usefulness. No metabolic stimulation due to L-canitina could be demonstrated in our experimental conditions.

Characterizing the effects of inorganic acid and alkaline shock on the Staphylococcus aureus transcriptome and messenger RNA turnover.

PubMed

Anderson, Kelsi L; Roux, Christelle M; Olson, Matthew W; Luong, Thanh T; Lee, Chia Y; Olson, Robert; Dunman, Paul M

2010-12-01

Staphylococcus aureus pathogenesis can be attributed partially to its ability to adapt to otherwise deleterious host-associated stresses. Here, Affymetrix GeneChips® were used to examine the S. aureus responses to inorganic acid and alkaline shock and to assess whether stress-dependent changes in mRNA turnover are likely to facilitate the organism's ability to tolerate a pH challenge. The results indicate that S. aureus adapts to pH shock by eliciting responses expected of cells coping with pH alteration, including neutralizing cellular pH, DNA repair, amino acid biosynthesis, and virulence factor expression. Further, the S. aureus response to alkaline conditions is strikingly similar to that of stringent response-induced cells. Indeed, we show that alkaline shock stimulates the accumulation of the stringent response activator (p)ppGpp. The results also revealed that pH shock significantly alters the mRNA properties of the cell. A comparison of the mRNA degradation properties of transcripts whose titers either increased or decreased in response to a sudden pH change revealed that alterations in mRNA degradation may, in part, account for the changes in the mRNA levels of factors predicted to mediate pH tolerance. A set of small stable RNA molecules were induced in response to acid- or alkaline-shock conditions and may mediate adaptation to pH stress. © 2010 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

Concomitant production of detergent compatible enzymes by Bacillus flexus XJU-1.

PubMed

Niyonzima, Francois N; More, Sunil S

2014-01-01

A soil screened Bacillus flexus XJU-1 was induced to simultaneously produce alkaline amylase, alkaline lipase and alkaline protease at their optimum levels on a common medium under submerged fermentation. The basal cultivation medium consisted of 0.5% casein, 0.5% starch and 0.5% cottonseed oil as an inducer for protease, amylase, and lipase, respectively. The casein also served as nitrogen source for all 3 enzymes. The starch was also found to act as carbon source additive for both lipase and protease. Maximum enzyme production occurred on fermentation medium with 1.5% casein, 1.5% soluble starch, 2% cottonseed oil, 2% inoculum size, initial pH of 11.0, incubation temperature of 37 °C and 1% soybean meal as a nitrogen source supplement. The analysis of time course study showed that 24 h was optimum incubation time for amylase whereas 48 h was the best time for both lipase and protease. After optimization, a 3.36-, 18.64-, and 27.33-fold increase in protease, amylase and lipase, respectively was recorded. The lipase was produced in higher amounts (37.72 U/mL) than amylase and protease about 1.27 and 5.85 times, respectively. As the 3 enzymes are used in detergent formulations, the bacterium can be commercially exploited to secrete the alkaline enzymes for use in detergent industry. This is the first report for concomitant production of 3 alkaline enzymes by a bacterium.

The Effects of Tissue-Nonspecific Alkaline Phosphatase Gene Therapy on Craniosynostosis and Craniofacial Morphology in the FGFR2C342Y/+ Mouse Model of Crouzon Craniosynostosis

PubMed Central

Wang, E; Nam, HK; Liu, J; Hatch, NE

2015-01-01

Objectives Craniosynostosis, the premature fusion of cranial bones, has traditionally been described as a disease of increased bone mineralization. However, multiple mouse models of craniosynostosis display craniosynostosis simultaneously with diminished cranial bone volume and/or density. We propose an alternative hypothesis that craniosynostosis results from abnormal tissue mineralization through the downregulation of tissue-nonspecific alkaline phosphatase (TNAP) enzyme downstream of activating mutations in FGFRs. Material & Methods Neonatal Crouzon (FGFRC342Y/+) and wild type (FGFR+/+) mice were injected with lentivirus to deliver a recombinant form of TNAP. Mice were sacrificed at four weeks post-natal. Serum was collected to test for alkaline phosphatase (AP), phosphorus, and calcium levels. Craniofacial bone fusion and morphology was assessed by micro-computed tomography. Results Injection with the TNAP lentivirus significantly increased serum AP levels (increased serum AP levels are indicative of efficient transduction and production of the recombinant protein), but results were variable and dependent upon viral lot and the litter of mice injected. Morphologic analysis revealed craniofacial form differences for inferior surface (p=.023) and cranial height (p=.014) regions between TNAP lentivirus injected and vehicle-injected Crouzon mice. With each unit increase in AP level, the odds of lambdoid suture fusion decreased by 84.2% and these results came close to statistical significance (p=.068). Conclusion These results suggest that TNAP deficiency may mediate FGFR2-associated craniosynostosis. Future studies should incorporate injection of recombinant TNAP protein, to avoid potential side effects and variable efficacy of lentiviral gene delivery. PMID:25865549

Conditions Inducing Excessive O-GlcNAcylation Inhibit BMP2-Induced Osteogenic Differentiation of C2C12 Cells.

PubMed

Gu, Hanna; Song, Mina; Boonanantanasarn, Kanitsak; Baek, Kyunghwa; Woo, Kyung Mi; Ryoo, Hyun-Mo; Baek, Jeong-Hwa

2018-01-09

Hyperglycemic conditions in diabetic patients can affect various cellular functions, including the modulation of osteogenic differentiation. However, the molecular mechanisms by which hyperglycemia affects osteogenic differentiation are yet to be clarified. This study aimed to investigate whether the aberrant increase in protein O -linked-β- N -acetylglucosamine glycosylation ( O -GlcNAcylation) contributes to the suppression of osteogenic differentiation due to hyperglycemia. To induce osteogenic differentiation, C2C12 cells were cultured in the presence of recombinant human bone morphogenetic protein 2 (BMP2). Excessive protein O -GlcNAcylation was induced by treating C2C12 cells with high glucose, glucosamine, or N -acetylglucosamine concentrations or by O -GlcNAc transferase (OGT) overexpression. The effect of O -GlcNAcylation on osteoblast differentiation was then confirmed by examining the expression levels of osteogenic marker gene mRNAs, activity of alkaline phosphatase, and transcriptional activity of Runx2, a critical transcription factor for osteoblast differentiation and bone formation. Cell treatment with high glucose, glucosamine or N -acetylglucosamine increased O -GlcNAcylation of Runx2 and the total levels of O -GlcNAcylated proteins, which led to a decrease in the transcriptional activity of Runx2, expression levels of osteogenic marker genes (Runx2, osterix, alkaline phosphatase, and type I collagen), and activity of alkaline phosphatase. These inhibitory effects were rescued by lowering protein O -GlcNAcylation levels by adding STO45849, an OGT inhibitor, or by overexpressing β- N -acetylglucosaminidase. Our findings suggest that excessive protein O -GlcNAcylation contributes to high glucose-suppressed osteogenic differentiation.

Understanding Local Ecology: Syllabus for Monitoring Water Quality.

ERIC Educational Resources Information Center

Iowa Univ., Iowa City.

This syllabus gives detailed information on monitoring water quality for teachers and students. It tells how to select a sample site; how to measure physical characteristics such as temperature, turbidity, and stream velocity; how to measure chemical parameters such as alkalinity, dissolved oxygen levels, phosphate levels, and ammonia nitrogen…

Antibiotic Effects on Methicillin-Resistant Staphylococcus aureus Cytoplasmic Peptidoglycan Intermediate Levels and Evidence for Potential Metabolite Level Regulatory Loops.

PubMed

Vemula, Harika; Ayon, Navid J; Burton, Alloch; Gutheil, William G

2017-06-01

Cytoplasmic peptidoglycan (PG) precursor levels were determined in methicillin-resistant Staphylococcus aureus (MRSA) after exposure to several cell wall-targeting antibiotics. Three experiments were performed: (i) exposure to 4× MIC levels (acute); (ii) exposure to sub-MIC levels (subacute); (iii) a time course experiment of the effect of vancomycin. In acute exposure experiments, fosfomycin increased UDP-GlcNAc, as expected, and resulted in substantially lower levels of total UDP-linked metabolite accumulation relative to other pathway inhibitors, indicating reduced entry into this pathway. Upstream inhibitors (fosfomycin, d-cycloserine, or d-boroalanine) reduced UDP-MurNAc-pentapeptide levels by more than fourfold. Alanine branch inhibitors (d-cycloserine and d-boroalanine) reduced d-Ala-d-Ala levels only modestly (up to 4-fold) but increased UDP-MurNAc-tripeptide levels up to 3,000-fold. Downstream pathway inhibitors (vancomycin, bacitracin, moenomycin, and oxacillin) increased UDP-MurNAc-pentapeptide levels up to 350-fold and UDP-MurNAc-l-Ala levels up to 80-fold, suggesting reduced MurD activity by downstream inhibitor action. Sub-MIC exposures demonstrated effects even at 1/8× MIC which strongly paralleled acute exposure changes. Time course data demonstrated that UDP-linked intermediate levels respond rapidly to vancomycin exposure, with several intermediates increasing three- to sixfold within minutes. UDP-linked intermediate level changes were also multiphasic, with some increasing, some decreasing, and some increasing and then decreasing. The total (summed) UDP-linked intermediate pool increased by 1,475 μM/min during the first 10 min after vancomycin exposure, providing a revised estimate of flux in this pathway during logarithmic growth. These observations outline the complexity of PG precursor response to antibiotic exposure in MRSA and indicate likely sites of regulation (entry and MurD). Copyright © 2017 American Society for Microbiology.

Environmental exposure to human carcinogens in teenagers and the association with DNA damage.

PubMed

Franken, Carmen; Koppen, Gudrun; Lambrechts, Nathalie; Govarts, Eva; Bruckers, Liesbeth; Den Hond, Elly; Loots, Ilse; Nelen, Vera; Sioen, Isabelle; Nawrot, Tim S; Baeyens, Willy; Van Larebeke, Nicolas; Boonen, Francis; Ooms, Daniëlla; Wevers, Mai; Jacobs, Griet; Covaci, Adrian; Schettgen, Thomas; Schoeters, Greet

2017-01-01

We investigated whether human environmental exposure to chemicals that are labeled as (potential) carcinogens leads to increased (oxidative) damage to DNA in adolescents. Six hundred 14-15-year-old youngsters were recruited all over Flanders (Belgium) and in two areas with important industrial activities. DNA damage was assessed by alkaline and formamidopyrimidine DNA glycosylase (Fpg) modified comet assays in peripheral blood cells and analysis of urinary 8-hydroxydeoxyguanosine (8-OHdG) levels. Personal exposure to potentially carcinogenic compounds was measured in urine, namely: chromium, cadmium, nickel, 1-hydroxypyrene as a proxy for exposure to other carcinogenic polycyclic aromatic hydrocarbons (PAHs), t,t-muconic acid as a metabolite of benzene, 2,5-dichlorophenol (2,5-DCP), organophosphate pesticide metabolites, and di(2-ethylhexyl) phthalate (DEHP) metabolites. In blood, arsenic, polychlorinated biphenyl (PCB) congeners 118 and 156, hexachlorobenzene (HCB), dichlorodiphenyltrichloroethane (DDT) and perfluorooctanoic acid (PFOA) were analyzed. Levels of methylmercury (MeHg) were measured in hair. Multiple linear regression models were used to establish exposure-response relationships. Biomarkers of exposure to PAHs and urinary chromium were associated with higher levels of both 8-OHdG in urine and DNA damage detected by the alkaline comet assay. Concentrations of 8-OHdG in urine increased in relation with increasing concentrations of urinary t,t-muconic acid, cadmium, nickel, 2,5-DCP, and DEHP metabolites. Increased concentrations of PFOA in blood were associated with higher levels of DNA damage measured by the alkaline comet assay, whereas DDT was associated in the same direction with the Fpg-modified comet assay. Inverse associations were observed between blood arsenic, hair MeHg, PCB 156 and HCB, and urinary 8-OHdG. The latter exposure biomarkers were also associated with higher fish intake. Urinary nickel and t,t-muconic acid were inversely associated with the alkaline comet assay. This cross-sectional study found associations between current environmental exposure to (potential) human carcinogens in 14-15-year-old Flemish adolescents and short-term (oxidative) damage to DNA. Prospective follow-up will be required to investigate whether long-term effects may occur due to complex environmental exposures. Copyright © 2016 Elsevier Inc. All rights reserved.

Hyperfine structure of 2Σ molecules containing alkaline-earth-metal atoms

NASA Astrophysics Data System (ADS)

Aldegunde, Jesus; Hutson, Jeremy M.

2018-04-01

Ultracold molecules with both electron spin and an electric dipole moment offer new possibilities in quantum science. We use density-functional theory to calculate hyperfine coupling constants for a selection of molecules important in this area, including RbSr, LiYb, RbYb, CaF, and SrF. We find substantial hyperfine coupling constants for the fermionic isotopes of the alkaline-earth-metal and Yb atoms. We discuss the hyperfine level patterns and Zeeman splittings expected for these molecules. The results will be important both to experiments aimed at forming ultracold open-shell molecules and to their applications.

Radio and Television Servicing. Intermediate Course.

ERIC Educational Resources Information Center

Campbell, Guy; And Others

Several intermediate performance objectives and corresponding criterion measures are listed for each of 32 terminal objectives for an intermediate (second year) radio/TV servicing course. This 1-year course (3 hours daily) was designed to provide the student with the basic skills and knowledges necessary for entry level employment in the Radio/TV…

Business Machine Maintenance. Performance Objectives. Intermediate Course.

ERIC Educational Resources Information Center

McMinn, Robert

Several intermediate performance objectives and corresponding criterion measures are listed for each of 28 terminal objectives presented in this guide for an intermediate business machine maintenance course at the secondary level. (For the basic course guide see CE 010 949.) Titles of the 28 terminal objective sections are Career Opportunities,…

Gasoline Engine Mechanics. Performance Objectives. Intermediate Course.

ERIC Educational Resources Information Center

Jones, Marion

Several intermediate performance objectives and corresponding criterion measures are listed for each of six terminal objectives presented in this curriculum guide for an intermediate gasoline engine mechanics course at the secondary level. (For the beginning course guide see CE 010 947.) The materials were developed for a two-semester (2 hour…

Masonry. Performance Objectives. Intermediate Course.

ERIC Educational Resources Information Center

Thompson, Moses

Several intermediate performance objectives and corresponding criterion measures are listed for each of 13 terminal objectives for an intermediate masonry course. These materials, developed for a two-semester (3 hours daily) course, are designed to provide the student with the skills and knowledge necessary for entry level employment in the field…

Validation of the da Vinci Surgical Skill Simulator across three surgical disciplines: A pilot study

PubMed Central

Alzahrani, Tarek; Haddad, Richard; Alkhayal, Abdullah; Delisle, Josée; Drudi, Laura; Gotlieb, Walter; Fraser, Shannon; Bergman, Simon; Bladou, Frank; Andonian, Sero; Anidjar, Maurice

2013-01-01

Objective: In this paper, we evaluate face, content and construct validity of the da Vinci Surgical Skills Simulator (dVSSS) across 3 surgical disciplines. Methods: In total, 48 participants from urology, gynecology and general surgery participated in the study as novices (0 robotic cases performed), intermediates (1–74) or experts (≥75). Each participant completed 9 tasks (Peg board level 2, match board level 2, needle targeting, ring and rail level 2, dots and needles level 1, suture sponge level 2, energy dissection level 1, ring walk level 3 and tubes). The Mimic Technologies software scored each task from 0 (worst) to 100 (best) using several predetermined metrics. Face and content validity were evaluated by a questionnaire administered after task completion. Wilcoxon test was used to perform pair wise comparisons. Results: The expert group comprised of 6 attending surgeons. The intermediate group included 4 attending surgeons, 3 fellows and 5 residents. The novices included 1 attending surgeon, 1 fellow, 13 residents, 13 medical students and 2 research assistants. The median number of robotic cases performed by experts and intermediates were 250 and 9, respectively. The median overall realistic score (face validity) was 8/10. Experts rated the usefulness of the simulator as a training tool for residents (content validity) as 8.5/10. For construct validity, experts outperformed novices in all 9 tasks (p < 0.05). Intermediates outperformed novices in 7 of 9 tasks (p < 0.05); there were no significant differences in the energy dissection and ring walk tasks. Finally, experts scored significantly better than intermediates in only 3 of 9 tasks (matchboard, dots and needles and energy dissection) (p < 0.05). Conclusions: This study confirms the face, content and construct validities of the dVSSS across urology, gynecology and general surgery. Larger sample size and more complex tasks are needed to further differentiate intermediates from experts. PMID:23914275

The intermediate disturbance hypothesis applies to tropical forests, but disturbance contributes little to tree diversity.

PubMed

Bongers, Frans; Poorter, Lourens; Hawthorne, William D; Sheil, Douglas

2009-08-01

The intermediate disturbance hypothesis (IDH) predicts local species diversity to be maximal at an intermediate level of disturbance. Developed to explain species maintenance and diversity patterns in species-rich ecosystems such as tropical forests, tests of IDH in tropical forest remain scarce, small-scale and contentious. We use an unprecedented large-scale dataset (2504 one-hectare plots and 331,567 trees) to examine whether IDH explains tree diversity variation within wet, moist and dry tropical forests, and we analyse the underlying mechanism by determining responses within functional species groups. We find that disturbance explains more variation in diversity of dry than wet tropical forests. Pioneer species numbers increase with disturbance, shade-tolerant species decrease and intermediate species are indifferent. While diversity indeed peaks at intermediate disturbance levels little variation is explained outside dry forests, and disturbance is less important for species richness patterns in wet tropical rain forests than previously thought.

ESL for Hotel/Hospitality Industry. Level: Advanced Beginner/Intermediate.

ERIC Educational Resources Information Center

Western Suffolk County Board of Cooperative Educational Services, Northport, NY.

This document contains 16 lesson plans for an advanced beginning and intermediate course in work-related English for non-English- or limited-English-speaking entry-level employees in the hotel and hospitality industry. Course objectives are as follows: helping participants understand and use job-specific vocabulary; receive and understand…

42 CFR 435.622 - Individuals in institutions who are eligible under a special income level.

Code of Federal Regulations, 2010 CFR

2010-10-01

... THE STATES, DISTRICT OF COLUMBIA, THE NORTHERN MARIANA ISLANDS, AND AMERICAN SAMOA General Financial..., nursing facilities, and intermediate care facilities for the mentally retarded who would not be eligible... (hospital, nursing facility, or intermediate level care for the mentally retarded), or by other factors...

Use of response surface methodology in a fed-batch process for optimization of tricarboxylic acid cycle intermediates to achieve high levels of canthaxanthin from Dietzia natronolimnaea HS-1.

PubMed

Nasri Nasrabadi, Mohammad Reza; Razavi, Seyed Hadi

2010-04-01

In this work, we applied statistical experimental design to a fed-batch process for optimization of tricarboxylic acid cycle (TCA) intermediates in order to achieve high-level production of canthaxanthin from Dietzia natronolimnaea HS-1 cultured in beet molasses. A fractional factorial design (screening test) was first conducted on five TCA cycle intermediates. Out of the five TCA cycle intermediates investigated via screening tests, alfaketoglutarate, oxaloacetate and succinate were selected based on their statistically significant (P<0.05) and positive effects on canthaxanthin production. These significant factors were optimized by means of response surface methodology (RSM) in order to achieve high-level production of canthaxanthin. The experimental results of the RSM were fitted with a second-order polynomial equation by means of a multiple regression technique to identify the relationship between canthaxanthin production and the three TCA cycle intermediates. By means of this statistical design under a fed-batch process, the optimum conditions required to achieve the highest level of canthaxanthin (13172 + or - 25 microg l(-1)) were determined as follows: alfaketoglutarate, 9.69 mM; oxaloacetate, 8.68 mM; succinate, 8.51 mM. Copyright 2009 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Stabilization of Pt monolayer catalysts under harsh conditions of fuel cells

DOE PAGES

Zhang, Xiaoming; Liu, Ping; Yu, Shansheng; ...

2015-05-21

We employed density functional theory (DFT) to explore the stability of core (M = Cu, Ru, Rh, Pd, Ag, Os, Ir, Au)-shell (Pt) catalysts under harsh conditions, including solutions and reaction intermediates involved in the oxygen reduction reaction (ORR) in fuel cells. A pseudomorphic surface alloy (PSA) with a Pt monolayer (Pt 1ML) supported on an M surface, Pt 1ML/M(111) or (001), was considered as a model system. Different sets of candidate M cores were identified to achieve a stable Pt 1ML shell depending on the conditions. In vacuum conditions, the Pt 1ML shell can be stabilized on the mostmore » of M cores except Cu, Ag, and Au. The situation varies under various electrochemical conditions. Depending on the solutions and the operating reaction pathways of the ORR, different M should be considered. Pd and Ir are the only core metals studied, being able to keep the Pt ML shell intact in perchloric acid, sulfuric acid, phosphoric acid, and alkaline solutions as well as under the ORR conditions via different pathways. Ru and Os cores should also be paid attention, which only fall during the ORR via the *OOH intermediate. Rh core works well as long as the ORR does not undergo the pathway via *O intermediate. Our results show that PSAs can behave differently from the near surface alloy, Pt 1ML/M 1ML/Pt(111), highlighting the importance of considering both chemical environments and the atomic structures in rational design of highly stable core-shell nanocatalysts. Finally, the roles that d-band center of a core M played in determining the stability of supported Pt 1ML shell were also discussed.« less

Stabilization of Pt monolayer catalysts under harsh conditions of fuel cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Xiaoming; Yu, Shansheng; Zheng, Weitao, E-mail: wtzheng@jlu.edu.cn, E-mail: pingliu3@bnl.gov

2015-05-21

We employed density functional theory to explore the stability of core (M = Cu, Ru, Rh, Pd, Ag, Os, Ir, Au)-shell (Pt) catalysts under harsh conditions, including solutions and reaction intermediates involved in the oxygen reduction reaction (ORR) in fuel cells. A pseudomorphic surface alloy (PSA) with a Pt monolayer (Pt{sub 1ML}) supported on an M surface, Pt{sub 1ML}/M(111) or (001), was considered as a model system. Different sets of candidate M cores were identified to achieve a stable Pt{sub 1ML} shell depending on the conditions. In vacuum conditions, the Pt{sub 1ML} shell can be stabilized on the most ofmore » M cores except Cu, Ag, and Au. The situation varies under various electrochemical conditions. Depending on the solutions and the operating reaction pathways of the ORR, different M should be considered. Pd and Ir are the only core metals studied, being able to keep the Pt{sub ML} shell intact in perchloric acid, sulfuric acid, phosphoric acid, and alkaline solutions as well as under the ORR conditions via different pathways. Ru and Os cores should also be paid attention, which only fall during the ORR via the *OOH intermediate. Rh core works well as long as the ORR does not undergo the pathway via *O intermediate. Our results show that PSAs can behave differently from the near surface alloy, Pt{sub 1ML}/M{sub 1ML}/Pt(111), highlighting the importance of considering both chemical environments and the atomic structures in rational design of highly stable core-shell nanocatalysts. Finally, the roles that d-band center of a core M played in determining the stability of supported Pt{sub 1ML} shell were also discussed.« less

Cripple Creek and other alkaline-related gold deposits in the Southern Rocky Mountains, USA: Influence of regional tectonics

USGS Publications Warehouse

Kelley, K.D.; Ludington, S.

2002-01-01

Alkaline-related epithermal vein, breccia, disseminated, skarn, and porphyry gold deposits form a belt in the southern Rocky Mountains along the eastern edge of the North American Cordillera. Alkaline igneous rocks and associated hydrothermal deposits formed at two times. The first was during the Laramide orogeny (about 70-40 Ma), with deposits restricted spatially to the Colorado mineral belt (CMB). Other alkaline igneous rocks and associated gold deposits formed later, during the transition from a compressional to an extensional regime (about 35-27 Ma). These younger rocks and associated deposits are more widespread, following the Rocky Mountain front southward, from Cripple Creek in Colorado through New Mexico. All of these deposits are on the eastern margin of the Cordillera, with voluminous calc-alkaline rocks to the west. The largest deposits in the belt include Cripple Creek and those in the CMB. The most important factor in the formation of all of the gold deposits was the near-surface emplacement of relatively oxidized volatile-rich alkaline magmas. Strontium and lead isotope compositions suggest that the source of the magmas was subduction-modified subcontinental lithosphere. However, Cripple Creek alkaline rocks and older Laramide alkaline rocks in the CMB that were emplaced through hydrously altered LREE-enriched rocks of the Colorado (Yavapai) province have 208Pb/204Pb ratios that suggest these magmas assimilated and mixed with significant amounts of lower crust. The anomalously hot, thick, and light crust beneath Colorado may have been a catalyst for large-scale transfer of volatiles and crustal melting. Increased dissolved H2O (and CO2, F, Cl) of these magmas may have resulted in more productive gold deposits due to more efficient magmatic-hydrothermal systems. High volatile contents may also have promoted Te and V enrichment, explaining the presence of fluorite, roscoelite (vanadium-rich mica) and tellurides in the CMB deposits and Cripple Creek as opposed to deposits to the south. Deep-seated structures of regional extent that formed during the Proterozoic allowed the magmas to rise to shallow crustal levels. Proterozoic sites of intrusions at 1.65, 1.4, and 1.1 Ga were also important precursors to alkaline-related gold deposits. Many of the larger gold deposits are located at sites of Proterozoic intrusions, and are localized at the intersection of northeast-trending ductile shear zones formed during Mesoproterozoic deformation, and an important north-trending fault formed during 1.1 Ga rifting.

Two-photon excitation cross-section in light and intermediate atoms

NASA Technical Reports Server (NTRS)

Omidvar, K.

1980-01-01

The method of explicit summation over the intermediate states is used along with LS coupling to derive an expression for two-photon absorption cross section in light and intermediate atoms in terms of integrals over radial wave functions. Two selection rules, one exact and one approximate, are also derived. In evaluating the radial integrals, for low-lying levels, the Hartree-Fock wave functions, and for high-lying levels, hydrogenic wave functions obtained by the quantum defect method are used. A relationship between the cross section and the oscillator strengths is derived. Cross sections due to selected transitions in nitrogen, oxygen, and chlorine are given. The expression for the cross section is useful in calculating the two-photon absorption in light and intermediate atoms.

Reassessment of the risk factors for biochemical recurrence in D'Amico intermediate-risk prostate cancer treated using radical prostatectomy.

PubMed

Narita, Shintaro; Mitsuzuka, Koji; Tsuchiya, Norihiko; Koie, Takuya; Kawamura, Sadafumi; Ohyama, Chikara; Tochigi, Tatsuo; Yamaguchi, Takuhiro; Arai, Yoichi; Habuchi, Tomonori

2015-11-01

To assess the risk factors for biochemical recurrence in D'Amico intermediate-risk prostate cancer patients treated using radical prostatectomy. We retrospectively reviewed the medical records of 1268 men with prostate cancer treated using radical prostatectomy without neoadjuvant therapy. The association between various risk factors and biochemical recurrence was then statistically evaluated. The Kaplan-Meier method, log-rank tests and Cox proportional hazards models were used for statistical analysis. In the intermediate-risk group, 96 patients (14.5%) experienced biochemical recurrence during a median follow up of 41 months. In the intermediate-risk group, preoperative prostate-specific antigen level, prostate volume and prostate-specific antigen density were significant preoperative risk factors for biochemical recurrence, whereas other factors including age, primary Gleason 4, clinical stage >T2 and percentage of positive biopsies were not. In multivariate analysis, higher preoperative prostate-specific antigen level and density, and a smaller prostate volume were independent risk factors for biochemical recurrence in the intermediate-risk group. Biochemical recurrence-free survival of patients in the intermediate-risk group with a higher prostate-specific antigen level and density (≥15 ng/mL, ≥0.6 ng/mL/cm(3), respectively), and lower prostate volume (≤10 mL) was comparable with that of high-risk group individuals (P = 0.632, 0.494 and 0.961, respectively). Preoperative prostate-specific antigen, prostate volume and prostate-specific antigen density are significant risk factors for biochemical recurrence in D'Amico intermediate-risk prostate cancer patients treated using radical prostatectomy. Using these variables, a subset of the intermediate-risk patients can be identified as having equivalent outcomes to high-risk patients. © 2015 The Japanese Urological Association.

Posttranslational heterogeneity of bone alkaline phosphatase in metabolic bone disease.

PubMed

Langlois, M R; Delanghe, J R; Kaufman, J M; De Buyzere, M L; Van Hoecke, M J; Leroux-Roels, G G

1994-09-01

Bone alkaline phosphatase is a marker of osteoblast activity. In order to study the posttranscriptional modification (glycosylation) of bone alkaline phosphatase in bone disease, we investigated the relationship between mass and catalytic activity of bone alkaline phosphatase in patients with osteoporosis and hyperthyroidism. Serum bone alkaline phosphatase activity was measured after lectin precipitation using the Iso-ALP test kit. Mass concentration of bone alkaline phosphatase was determined with an immunoradiometric assay (Tandem-R Ostase). In general, serum bone alkaline phosphatase mass and activity concentration correlated well. The activity : mass ratio of bone alkaline phosphatase was low in hyperthyroidism. Activation energy of the reaction catalysed by bone alkaline phosphatase was high in osteoporosis and in hyperthyroidism. Experiments with neuraminidase digestion further demonstrated that the thermodynamic heterogeneity of bone alkaline phosphatase can be explained by a different glycosylation of the enzyme.

Spectrophotometric Measurements of the Carbonate Ion Concentration: Aragonite Saturation States in the Mediterranean Sea and Atlantic Ocean.

PubMed

Fajar, Noelia M; García-Ibáñez, Maribel I; SanLeón-Bartolomé, Henar; Álvarez, Marta; Pérez, Fiz F

2015-10-06

Measurements of ocean pH, alkalinity, and carbonate ion concentrations ([CO3(2-)]) during three cruises in the Atlantic Ocean and one in the Mediterranean Sea were used to assess the reliability of the recent spectrophotometric [CO3(2-)] methodology and to determine aragonite saturation states. Measurements of [CO3(2-)] along the Atlantic Ocean showed high consistency with the [CO3(2-)] values calculated from pH and alkalinity, with negligible biases (0.4 ± 3.4 μmol·kg(-1)). In the warm, salty, high alkalinity and high pH Mediterranean waters, the spectrophotometric [CO3(2-)] methodology underestimates the measured [CO3(2-)] (4.0 ± 5.0 μmol·kg(-1)), with anomalies positively correlated to salinity. These waters also exhibited high in situ [CO3(2-)] compared to the expected aragonite saturation. The very high buffering capacity allows the Mediterranean Sea waters to remain over the saturation level of aragonite for long periods of time. Conversely, the relatively thick layer of undersaturated waters between 500 and 1000 m depths in the Tropical Atlantic is expected to progress to even more negative undersaturation values. Moreover, the northern North Atlantic presents [CO3(2-)] slightly above the level of aragonite saturation, and the expected anthropogenic acidification could result in reductions of the aragonite saturation levels during future decades, acting as a stressor for the large population of cold-water-coral communities.

Performance and application of a fluidized bed limestone reactor designed for control of alkalinity, hardness and pH at the Warm Springs Regional Fisheries Center

USGS Publications Warehouse

Watten, Barnaby J.; Mudrak, Vincent A.; Echevarria, Carlos; Sibrell, Philip; Summerfelt, Steven T.; Boyd, Claude E.

2017-01-01

Springs serving the Warm Springs Regional Fisheries Center, Warm Springs, Georgia, have pH, alkalinity, and hardness levels thatlie under the range required for successful fish propagation while free CO2 is well above allowable targets. We evaluate a pretreatment process that exploits limestone’s (CaCO3) ability to react away hydrogen ions (H+) and carbon dioxide (CO2) while increasing alkalinity (HCO3−) and calcium (Ca2+) concentrations, i.e. CaCO3 + H+ ↔ HCO3− + Ca2+ CaCO3 + CO2 + H2O ↔ Ca2+ + 2HCO3− Limestone sand was tested in both pilot and full scale fluidized bed reactors (CycloBio®). We first established the bed expansion characteristics of three commercial limestone products then evaluated the effect of hydraulic flux and bed height on dissolution rate of a single selected product (Type A16 × 120). Pilot scale testing at 18C showed limestone dissolution rates were relatively insensitive to flux over the range 1.51–3.03 m3/min/m2 but were sensitive (P < 0.001; R2 = 0.881) to changes in bed height (BH, cm) over the range 83–165 cm following the relation: (Alkalinity, mg/L) = 123.51 − (3788.76 (BH)). Differences between filtered and non-filtered alkalinity were small(P > 0.05) demonstrating that limestone was present in the reactor effluent primarily in the form of dissolved Ca(HCO3)2. Effluent alkalinity exceeded our target level of 50 mg/L under most operating conditions evaluated with typical pilot scale values falling within the range of 90–100 mg/L despite influent concentrations of about 4 mg/L. Concurrently, CO2 fell from an average of 50.6 mg/L to 8.3 mg/L (90%), providing for an increase in pH from 5.27 to a mean of 7.71. The ability of the test reactor to provide changes in water chemistry variables that exceeded required changes allowed for a dilution ratio of 0.6. Here, alkalinity still exceeded 50 mg/L, the CO2 concentration remained well below our limit of 20 mg/L (15.4 mg/L) and the pH was near neutral (7.17). Applying the dilution ratio of 0.6 in a full scale treatment plant at the site reduced by 40% the volume of spring water that is directed through each of three parallel reactors that combined react away 49,000 kg of limestone/yr.

Cloning of a phenol oxidase gene from Acremonium murorum and its expression in Aspergillus awamori.

PubMed

Gouka, R J; van der Heiden, M; Swarthoff, T; Verrips, C T

2001-06-01

Fungal multicopper oxidases have many potential industrial applications, since they perform reactions under mild conditions. We isolated a phenol oxidase from the fungus Acremonium murorum var. murorum that was capable of decolorizing plant chromophores (such as anthocyanins). This enzyme is of interest in laundry-cleaning products because of its broad specificity for chromophores. We expressed an A. murorum cDNA library in Saccharomyces cerevisiae and subsequently identified enzyme-producing yeast colonies based on their ability to decolor a plant chromophore. The cDNA sequence contained an open reading frame of 1,806 bp encoding an enzyme of 602 amino acids. The phenol oxidase was overproduced by Aspergillus awamori as a fusion protein with glucoamylase, cleaved in vivo, and purified from the culture broth by hydrophobic-interaction chromatography. The phenol oxidase is active at alkaline pH (the optimum for syringaldazine is pH 9) and high temperature (optimum, 60 degrees C) and is fully stable for at least 1 h at 60 degrees C under alkaline conditions. These characteristics and the high production level of 0.6 g of phenol oxidase per liter in shake flasks, which is equimolar with the glucoamylase protein levels, make this enzyme suitable for use in processes that occur under alkaline conditions, such as laundry cleaning.

Cloning of a Phenol Oxidase Gene from Acremonium murorum and Its Expression in Aspergillus awamori

PubMed Central

Gouka, Robin J.; van der Heiden, Monique; Swarthoff, Ton; Verrips, C. Theo

2001-01-01

Fungal multicopper oxidases have many potential industrial applications, since they perform reactions under mild conditions. We isolated a phenol oxidase from the fungus Acremonium murorum var. murorum that was capable of decolorizing plant chromophores (such as anthocyanins). This enzyme is of interest in laundry-cleaning products because of its broad specificity for chromophores. We expressed an A. murorum cDNA library in Saccharomyces cerevisiae and subsequently identified enzyme-producing yeast colonies based on their ability to decolor a plant chromophore. The cDNA sequence contained an open reading frame of 1,806 bp encoding an enzyme of 602 amino acids. The phenol oxidase was overproduced by Aspergillus awamori as a fusion protein with glucoamylase, cleaved in vivo, and purified from the culture broth by hydrophobic-interaction chromatography. The phenol oxidase is active at alkaline pH (the optimum for syringaldazine is pH 9) and high temperature (optimum, 60°C) and is fully stable for at least 1 h at 60°C under alkaline conditions. These characteristics and the high production level of 0.6 g of phenol oxidase per liter in shake flasks, which is equimolar with the glucoamylase protein levels, make this enzyme suitable for use in processes that occur under alkaline conditions, such as laundry cleaning. PMID:11375170

Evaluation of various parameters of calcium-alginate immobilization method for enhanced alkaline protease production by Bacillus licheniformis NCIM-2042 using statistical methods.

PubMed

Potumarthi, Ravichandra; Subhakar, Ch; Pavani, A; Jetty, Annapurna

2008-04-01

Calcium-alginate immobilization method for the production of alkaline protease by Bacillus licheniformis NCIM-2042 was optimized statistically. Four variables, such as sodium-alginate concentration, calcium chloride concentration, inoculum size and agitation speed were optimized by 2(4) full factorial central composite design and subsequent analysis and model validation by a second-order regression equation. Eleven carbon, 11 organic nitrogen and seven inorganic nitrogen sources were screened by two-level Plackett-Burman design for maximum alkaline protease production by using optimized immobilized conditions. The levels of four variables, such as Na-alginate 2.78%; CaCl(2), 2.15%; inoculum size, 8.10% and agitation, 139 rpm were found to be optimum for maximal production of protease. Glucose, soybean meal and ammonium sulfate were resulted in maximum protease production at 644 U/ml, 720 U/ml, and 806 U/ml when screened for carbon, organic nitrogen and inorganic nitrogen sources, respectively, using optimized immobilization conditions. Repeated fed batch mode of operation, using optimized immobilized conditions, resulted in continuous operation for 12 cycles without disintegration of beads. Cross-sectional scanning electron microscope images have shown the growth pattern of B. licheniformis in Ca-alginate immobilized beads.

How Do Transfer Students Perform in Economics? Evidence from Intermediate Macroeconomics

ERIC Educational Resources Information Center

Asarta, Carlos J.; Fuess, Scott M., Jr.; Perumal, Andrew

2013-01-01

For students taking intermediate-level economics, does it matter where they studied principles of economics? Does transferring college credit influence subsequent academic performance in economics? With a sample covering 1999-2008, the authors analyze in this article a group of nearly 1,000 students taking intermediate macroeconomics at a…

Generic method for the absolute quantification of glutathione S-conjugates: Application to the conjugates of acetaminophen, clozapine and diclofenac.

PubMed

den Braver, Michiel W; Vermeulen, Nico P E; Commandeur, Jan N M

2017-03-01

Modification of cellular macromolecules by reactive drug metabolites is considered to play an important role in the initiation of tissue injury by many drugs. Detection and identification of reactive intermediates is often performed by analyzing the conjugates formed after trapping by glutathione (GSH). Although sensitivity of modern mass spectrometrical methods is extremely high, absolute quantification of GSH-conjugates is critically dependent on the availability of authentic references. Although 1 H NMR is currently the method of choice for quantification of metabolites formed biosynthetically, its intrinsically low sensitivity can be a limiting factor in quantification of GSH-conjugates which generally are formed at low levels. In the present study, a simple but sensitive and generic method for absolute quantification of GSH-conjugates is presented. The method is based on quantitative alkaline hydrolysis of GSH-conjugates and subsequent quantification of glutamic acid and glycine by HPLC after precolumn derivatization with o-phthaldialdehyde/N-acetylcysteine (OPA/NAC). Because of the lower stability of the glycine OPA/NAC-derivate, quantification of the glutamic acid OPA/NAC-derivate appeared most suitable for quantification of GSH-conjugates. The novel method was used to quantify the concentrations of GSH-conjugates of diclofenac, clozapine and acetaminophen and quantification was consistent with 1 H NMR, but with a more than 100-fold lower detection limit for absolute quantification. Copyright © 2017. Published by Elsevier B.V.

The Impact of Alkaliphilic Biofilm Formation on the Release and Retention of Carbon Isotopes from Nuclear Reactor Graphite.

PubMed

Rout, S P; Payne, L; Walker, S; Scott, T; Heard, P; Eccles, H; Bond, G; Shah, P; Bills, P; Jackson, B R; Boxall, S A; Laws, A P; Charles, C; Williams, S J; Humphreys, P N

2018-03-13

14 C is an important consideration within safety assessments for proposed geological disposal facilities for radioactive wastes, since it is capable of re-entering the biosphere through the generation of 14 C bearing gases. The irradiation of graphite moderators in the UK gas-cooled nuclear power stations has led to the generation of a significant volume of 14 C-containing intermediate level wastes. Some of this 14 C is present as a carbonaceous deposit on channel wall surfaces. Within this study, the potential of biofilm growth upon irradiated and 13 C doped graphite at alkaline pH was investigated. Complex biofilms were established on both active and simulant samples. High throughput sequencing showed the biofilms to be dominated by Alcaligenes sp at pH 9.5 and Dietzia sp at pH 11.0. Surface characterisation revealed that the biofilms were limited to growth upon the graphite surface with no penetration of the deeper porosity. Biofilm formation resulted in the generation of a low porosity surface layer without the removal or modification of the surface deposits or the release of the associated 14 C/ 13 C. Our results indicated that biofilm formation upon irradiated graphite is likely to occur at the pH values studied, without any additional release of the associated 14 C.

PdCo porous nanostructures decorated on polypyrrole @ MWCNTs conductive nanocomposite-Modified glassy carbon electrode as a powerful catalyst for ethanol electrooxidation

NASA Astrophysics Data System (ADS)

Fard, Leyla Abolghasemi; Ojani, Reza; Raoof, Jahan Bakhsh; Zare, Ehsan Nazarzadeh; Lakouraj, Moslem Mansour

2017-04-01

In the current study, well-defined PdCo porous nanostructure (PdCo PNS) is prepared by a simple one-pot wet-chemical method and polypyrrole@multi-walled carbon nanotubes (PPy@MWCNTs) nanocomposite is used as a catalyst support. The morphology and the structural properties of the prepared catalyst were studied by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). The electrocatalytic performance of PdCo PNS/PPy@MWCNTs on glassy carbon electrode has been evaluated by cyclic voltammetry (CV), chronoamperometry (CA) and electrochemical impedance spectroscopy (EIS) techniques. The specific activity of PdCo PNS/PPy@MWCNTs for ethanol electrooxidation (1.65 mA cm-2) is higher than those of other compared electrocatalysts. Also, PdCo PNS/PPy@MWCNTs catalyst represented higher electrocatalytic activity, better long-term stability and high level of poisoning tolerance to the carbonaceous oxidative intermediates for ethanol electrooxidation reaction in alkaline media. Furthermore, the presence of PPY@MWCNTs on the surface of GCE produce a high activity to electrocatalyst, which might be due to the easier charge transfer at polymer/carbon nanotubes interfaces, higher electrochemically accessible surface areas and electronic conductivity. The superior catalytic activity of PdCo PNS/PPy@MWCNTs suggests it to be as a promising electrocatalyst for future direct ethanol fuel cells.

Effects of dietary supplementation with vitamin C and vitamin E and their combination on growth performance, some biochemical parameters, and oxidative stress induced by copper toxicity in broilers.

PubMed

Cinar, Miyase; Yildirim, Ebru; Yigit, A Arzu; Yalcinkaya, Ilkay; Duru, Ozkan; Kisa, Uçler; Atmaca, Nurgul

2014-05-01

This study investigated effects of dietary supplementation with vitamin C, vitamin E on performance, biochemical parameters, and oxidative stress induced by copper toxicity in broilers. A total of 240, 1-day-old, broilers were assigned to eight groups with three replicates of 10 chicks each. The groups were fed on the following diets: control (basal diet), vitamin C (250 mg/kg diet), vitamin E (250 mg/kg diet), vitamin C + vitamin E (250 mg/kg + 250 mg/kg diet), and copper (300 mg/kg diet) alone or in combination with the corresponding vitamins. At the 6th week, the body weights of broilers were decreased in copper, copper + vitamin E, and copper + vitamin C + vitamin E groups compared to control. The feed conversion ratio was poor in copper group. Plasma aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase activities, iron, copper concentrations, and erythrocyte malondialdehyde were increased; plasma vitamin A and C concentrations and erythrocyte superoxide dismutase were decreased in copper group compared to control. Glutathione peroxidase, vitamin C, and iron levels were increased; aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and copper levels were decreased in copper + vitamin C group, while superoxide dismutase, glutathione peroxidase, and vitamin E concentrations were increased; aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase were decreased in copper with vitamin E group compared to copper group. The vitamin C concentrations were increased; copper, uric acid, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and malondialdehyde were decreased in copper + vitamin C + vitamin E group compared to copper group. To conclude, copper caused oxidative stress in broilers. The combination of vitamin C and vitamin E addition might alleviate the harmful effects of copper as demonstrated by decreased lipid peroxidation and hepatic enzymes.

Intracellular pH changes in human aortic smooth muscle cells in response to fluid shear stress

NASA Technical Reports Server (NTRS)

Stamatas, G. N.; Patrick, C. W. Jr; McIntire, L. V.

1997-01-01

The smooth muscle cell (SMC) layers of human arteries may be exposed to blood flow after endothelium denudation, for example, following balloon angioplasty treatment. These SMCs are also constantly subjected to pressure driven transmural fluid flow. Flow-induced shear stress can alter SMC growth and metabolism. Signal transduction mechanisms involved in these flow effects on SMCs are still poorly understood. In this work, the hypothesis that shear stress alters the intracellular pH (pHi) of SMC is examined. When exposed to venous and arterial levels of shear stress, human aortic smooth muscle cells (hASMC) undergo alkalinization. The alkalinization plateau persisted even after 20 min of cell exposure to flow. Addition of amiloride (10 micromoles) or its 5-(N-ethyl-N-isopropyl) analog (EIPA, 10 micromoles), both Na+/H+ exchanger inhibitors, attenuated intracellular alkalinization, suggesting the involvement of the Na+/H+ exchanger in this response. The same concentrations of these inhibitors did not show an effect on pHi of hASMCs in static culture. 4-Acetamido-4'-isothio-cyanatostilbene-2,2'-disulfonic acid (SITS, 1 mM), a Cl-/HCO3- exchange inhibitor, affected the pHi of hASMCs both in static and flow conditions. Our results suggest that flow may perturb the Na+/H+ exchanger leading to an alkalinization of hASMCs, a different response from the flow-induced acidification seen with endothelial cells at the same levels of shear stress. Understanding the flow-induced signal transduction pathways in the vascular cells is of great importance in the tissue engineering of vascular grafts. In the case of SMCs, the involvement of pHi changes in nitric oxide production and proliferation regulation highlights further the significance of such studies.

Absorption Coefficient of Alkaline Earth Halides.

DTIC Science & Technology

1980-04-01

not observed at low energy level , are developed at high power levels . No matter how low the absorption is. the effect is objectionable at high-energy... levels . As a natural consequence, the magnitude of the absorption coefficient is the key parameter in selecting laser window materials. Over the past...Presence of impurities can complicate the exponential tail. particularly at low absorption levels . The impurities may enter 12 the lattice singly or

Jurassic rifting at the Eurasian Tethys margin: Geochemical and geochronological constraints from granitoids of North Makran, southeastern Iran

NASA Astrophysics Data System (ADS)

Hunziker, Daniela; Burg, Jean-Pierre; Bouilhol, Pierre; von Quadt, Albrecht

2015-03-01

This study focuses on an east-west trending belt of granitic to intermediate intrusions and their volcanic cover in the northern Dur Kan Complex, a continental slice outcropping to the north of the exposed Makran accretionary wedge in southeastern Iran. Field observations, petrographic descriptions, trace element, and isotope analyses combined with U-Pb zircon geochronology are presented to determine the time frame of magmatism and tectonic setting during the formation of these rocks. Results document three magmatic episodes with different melt sources for (1) granites, (2) a diorite-trondhjemite-plagiogranite sequence, and (3) diabases and lavas. Granites, dated at 170-175 Ma, represent crystallized melt with a strong continental isotopic contribution. The diorite-trondhjemite-plagiogranite sequence is 165-153 Ma old and derives from a mantle magma source with minor continental contribution. East-west trending diabase dikes and bodies intruded the granitoids, which were eroded and then covered by Valanginian (140-133 Ma) alkaline lavas and sediments. Alkaline dikes and lavas have a mantle isotopic composition. Temporal correlation with plutonites of the Sanandaj-Sirjan Zone to the northwest defines a narrow, NW-SE striking and nearly 2000 km long belt of Jurassic intrusions. The increasing mantle influence in the magma sources is explained by thinning of continental lithosphere and related mantle upwelling/decompression melting. Accordingly, the formation of the studied igneous rocks is related to the extension of the Iranian continental margin, which ultimately led to the formation of the Tethys-related North Makran Ophiolites.

Combined in vitro transcription and reverse transcription to amplify and label complex synthetic oligonucleotide probe libraries.

PubMed

Murgha, Yusuf; Beliveau, Brian; Semrau, Kassandra; Schwartz, Donald; Wu, Chao-Ting; Gulari, Erdogan; Rouillard, Jean-Marie

2015-06-01

Oligonucleotide microarrays allow the production of complex custom oligonucleotide libraries for nucleic acid detection-based applications such as fluorescence in situ hybridization (FISH). We have developed a PCR-free method to make single-stranded DNA (ssDNA) fluorescent probes through an intermediate RNA library. A double-stranded oligonucleotide library is amplified by transcription to create an RNA library. Next, dye- or hapten-conjugate primers are used to reverse transcribe the RNA to produce a dye-labeled cDNA library. Finally the RNA is hydrolyzed under alkaline conditions to obtain the single-stranded fluorescent probes library. Starting from unique oligonucleotide library constructs, we present two methods to produce single-stranded probe libraries. The two methods differ in the type of reverse transcription (RT) primer, the incorporation of fluorescent dye, and the purification of fluorescent probes. The first method employs dye-labeled reverse transcription primers to produce multiple differentially single-labeled probe subsets from one microarray library. The fluorescent probes are purified from excess primers by oligonucleotide-bead capture. The second method uses an RNA:DNA chimeric primer and amino-modified nucleotides to produce amino-allyl probes. The excess primers and RNA are hydrolyzed under alkaline conditions, followed by probe purification and labeling with amino-reactive dyes. The fluorescent probes created by the combination of transcription and reverse transcription can be used for FISH and to detect any RNA and DNA targets via hybridization.

Potential of sustainable hierarchical zeolites in the valorization of α-pinene.

PubMed

Nuttens, Nicolas; Verboekend, Danny; Deneyer, Aron; Van Aelst, Joost; Sels, Bert F

2015-04-13

In the valorization of α-pinene, which is an important biomass intermediate derived from turpentine oil, hierarchical (mesoporous) zeolites represent a superior class of catalysts. Hierarchical USY, ZSM-5, and beta zeolites have been prepared, characterized, and catalytically evaluated, with the aim of combining the highest catalytic performance with the most sustainable synthetic protocol. These zeolites are prepared by alkaline treatment in aqueous solutions of NH4 OH, NaOH, diethylamine, and NaOH complemented with tetrapropylammonium bromide. The hierarchical USY zeolite is the most attractive catalyst of the tested series, and is able to combine an overall organic-free synthesis with an up to sixfold activity enhancement and comparable selectivity over the conventional USY zeolite. This superior performance relates to a threefold greater activity than that of the commercial standard, namely, H2 SO4 /TiO2 . Correlation of the obtained benefits to the amount of solid lost during the postsynthetic modifications highlights that the highest activity gains are obtained with minor leaching. Furthermore, a highly zeolitic character, as determined by bulk XRD, is beneficial, but not crucial, in the conversion of α-pinene. The alkaline treatments not only result in a higher overall activity, but also a more functional external surface area, attaining up to four times the pinene conversions per square nanometer. The efficiency of the hierarchical USY zeolite is concomitantly demonstrated in the conversion of limonene and turpentine oil, which emphasizes its industrial potential. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Course and Curriculum Improvement Materials: Mathematics, Science, Social Sciences - Elementary, Intermediate, Secondary.

ERIC Educational Resources Information Center

National Science Foundation, Washington, DC.

This is a list of curriculum improvement materials produced by major course and curriculum projects supported by the National Science Foundation's Division of Pre-College Education in Science. The materials are grouped by educational level (elementary, intermediate, and secondary) and within each level by broad discipline groupings (mathematics,…

Exploring Optimal Pronunciation Teaching: Integrating Instructional Software into Intermediate-Level EFL Classes in China

ERIC Educational Resources Information Center

Gao, Yang; Hanna, Barbara E.

2016-01-01

This study investigates the effectiveness of teaching pronunciation with instructional software to a cohort of Chinese learners of English aged 13 to 16 at lower-intermediate level. It also explores the relationship between learners' attitudes towards pronunciation and their pronunciation learning. Participants were 60 students at a language…

Intermediate Decoding Skills. NetNews. Volume 4, Number 4

ERIC Educational Resources Information Center

LDA of Minnesota, 2004

2004-01-01

Intermediate decoding refers to word analysis skills that are beyond a beginning, one-syllable level as described in an earlier NetNews issue, yet are just as important for building adult level reading proficiency. Research from secondary settings indicates that struggling readers in middle school or high school programs often read between the…

Vertical Integration at Junior and Intermediate Levels. School Research Newsletter.

ERIC Educational Resources Information Center

Marklund, Inger, Ed.; Hanse, Mona-Britt, Ed.

1984-01-01

In recent years, there has been a rapid growth of interest in Sweden in vertically integrated classes in compulsory schools, especially at junior high school and intermediate grade levels. This development is supported in various ways by the curriculum, partly because it puts more emphasis than previous curricula on the occurrence of teaching…

Assessment of Student Achievement: Evaluation of Student Achievement at the Intermediate Level. Final Report.

ERIC Educational Resources Information Center

Wahlstrom, M.; And Others

Evaluation and assessment procedures of Ontario, Canada principals and teachers at the Intermediate level (grades 7 and 8) were examined. Extensive questionnaires were returned by 134 principals and 225 teachers divided across the subject areas of English, Mathematics, Science, Languages, History, Home Economics or Shop, Arts, and Physical…

Viscosity of alkaline suspensions of ground black and white pepper samples: An indication or an identification of high dose radiation treatment?

NASA Astrophysics Data System (ADS)

Schreiber, G. A.; Leffke, A.; Mager, M.; Helle, N.; Bögl, K. W.

1994-11-01

Forty-nine pepper samples were taken from retail food stores of different cities in Germany. Most of the black and all white pepper samples showed high viscosity values after jellification in alkaline solution. After irradiation with a γ-ray dose of 6 kGy, viscosity was largely reduced in each case. Some black pepper samples showed a low viscosity level already before irradiation. However, thermoluminescence analysis did not reveal any sign for irradiation treatment prior to examination. Furthermore, the low viscosity level of these samples could not be correlated with a low starch content. It is concluded that the viscosity levels of irradiated white pepper samples clearly reveal high dose irradiation treatment. In case of black peppers it is judged that the method can be used to screen for irradiated samples since it is fast, easy and cheap. However, a positive result should be confirmed by another technique, e.g. thermoluminescence.

Antidiabetic and hypolipidemic effects of Dorema aucheri hydroalcoholic leave extract in streptozotocin-nicotinamide induced type 2 diabetes in male rats

PubMed Central

Ahangarpour, Akram; Zamaneh, Hossein Teymuri; Jabari, Ayob; Nia, Hamid Malekshahi; Heidari, Hamid

2014-01-01

Objective(s): The present study investigated the antidiabetic and hypolipidemic properties of Dorema aucheri leave hydroalcoholic extract in nicotinamide-streptozotocin induced type 2 diabetic rats. Materials and Methods: nicotinamide/streptozotocin-induced diabetic rats were supplemented orally with three different doses of D. aucheri (100, 200 and 400 mg/kg BW) or glibenclamide (0.25 mg/kg) for 4 weeks. Ultimately, blood of animals has taken and glucose, insulin, lipid profiles, SGPT, alkaline phosphatase, SGOT, leptin levels were assayed. Results: D. aucheri has highly significant blood glucose lowering effect. Administration of the extract to diabetic rats resulted in a remarkable change in serum lipid profiles, insulin and leptin levels relative to diabetic group. Also the extract reversed back the serum levels of SGPT, alkaline phosphatase and SGOT to near normal in treated diabetic rats. Conclusion: D. aucheri could be useful in treatment of diabetes. Moderate dose of D. aucheri (200 mg/kg) was more effective than the others. PMID:25729552

[Effect of low-intensity 900 MHz frequency electromagnetic radiation on rat liver and blood serum enzyme activities].

PubMed

Nersesova, L S; Petrosian, M S; Gazariants, M G; Mkrtchian, Z S; Meliksetian, G O; Pogosian, L G; Akopian, Zh I

2014-01-01

The comparative analysis of the rat liver and blood serum creatine kinase, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase and purine nucleoside phosphorylase post-radiation activity levels after a total two-hour long single and fractional exposure of the animals to low-intensity 900 MHz frequency electromagnetic field showed that the most sensitive enzymes to the both schedules of radiation are the liver creatine kinase, as well as the blood serum creatine kinase and alkaline phosphatase. According to the comparative analysis of the dynamics of changes in the activity level of the liver and blood serum creatine kinase, alanine aminotransferase, aspartate aminotransferase and purine nucleoside phosphorylase, both single and fractional radiation schedules do not affect the permeability of a hepatocyte cell membrane, but rather cause changes in their energetic metabolism. The correlation analysis of the post-radiation activity level changes of the investigated enzymes did not reveal a clear relationship between them. The dynamics of post-radiation changes in the activity of investigated enzyme levels following a single and short-term fractional schedules of radiation did not differ essentially.

Pt/Ceria-based Catalysts for Small Alcohol Electrooxidation

NASA Astrophysics Data System (ADS)

Menendez-Mora, Christian L.

High emissions of fossil-based energy sources have led to scientists around the world to develop new alternatives for the future. In this sense, fuel cells are a remarkable and promising energy option with less environmental impact. The most used fuels for this technology are hydrogen and small chain alcohols, which can be oxidized to transform their chemical energy into electrical power. To do this, fuel cells need catalysts that will act as an active surface where the oxidation can take place. The problem with platinum catalysts is its possible CO poisoning with intermediates that are produced before the complete oxidation of alcohol to CO2. Different approaches have been taken to try to resolve this issue. In this case, cerium oxide (ceria) was selected as a co-catalyst to mitigate the effect of CO poisoning of platinum. Ceria is a compound that has the ability to work as an "oxygen tank" and can donate oxygen to carbon monoxide that is strongly adsorbed at platinum surface to produce CO2 (carbon dioxide), regenerating the Pt surface for further alcohol oxidation. Therefore, enhancing the current density as well as the power output of a fuel cell. First, an occlusion deposition technique was used to prepare platinum/ceria composite electrodes and tested them towards small chain alcohol oxidation such as methanol oxidation reaction in acidic and alkaline media. The preliminary results demonstrated that the Pt/ceria electrodes were more efficient towards methanol electrooxidation when compared to Pt electrodes. This enhancement was attributed to the presence of ceria. A second preparation method was selected for the synthesis of ceria/Pt catalysts. In this case, a hydrothermal method was used and the catalysis were studied for the effect of MeOH, EtOH and n-BuOH oxidation. The observed effect was that electrodes made of Pt/Pt:CeO2-x showed better catalytic effect than Pt/ceria and platinum electrodes. Moreover, a comparison between ceria nanorods versus nanoparticles as substrates was done. The general result was that ceria nanoparticles showed better electrocatalytic behavior towards the oxidation of methanol in alkaline medium. Finally, as an outreach activity, an educational module to reinforce the electrochemical concepts in the General Chemistry Laboratory course at UPR-RP was developed. The module was based on Volta's Experiment and an improvement on students learning was detected when comparing this activity with the normal Daniel's cell experience that is used in most Universities at the undergraduate level. In summary, the findings of this thesis conclude that ceria is a compound that may enhance platinum catalytic activity by CO oxidation, promoting the oxidation of alcohols in acidic and alkaline medium. Moreover, catalysis depends on the morphology of the ceria that is used as the catalysts support.

Response to Long-Term NaHCO3-Derived Alkalinity in Model Lotus japonicus Ecotypes Gifu B-129 and Miyakojima MG-20: Transcriptomic Profiling and Physiological Characterization

PubMed Central

Rocco, Rubén; Bordenave, Cesar D.; Escaray, Francisco J.; Antonelli, Cristian; Calzadilla, Pablo; Gárriz, Andrés; Serna, Eva; Carrasco, Pedro; Menendez, Ana B.

2014-01-01

The current knowledge regarding transcriptomic changes induced by alkalinity on plants is scarce and limited to studies where plants were subjected to the alkaline salt for periods not longer than 48 h, so there is no information available regarding the regulation of genes involved in the generation of a new homeostatic cellular condition after long-term alkaline stress. Lotus japonicus is a model legume broadly used to study many important physiological processes including biotic interactions and biotic and abiotic stresses. In the present study, we characterized phenotipically the response to alkaline stress of the most widely used L. japonicus ecotypes, Gifu B-129 and MG-20, and analyzed global transcriptome of plants subjected to 10 mM NaHCO3 during 21 days, by using the Affymetrix Lotus japonicus GeneChip®. Plant growth assessment, gas exchange parameters, chlorophyll a fluorescence transient (OJIP) analysis and metal accumulation supported the notion that MG-20 plants displayed a higher tolerance level to alkaline stress than Gifu B-129. Overall, 407 and 459 probe sets were regulated in MG-20 and Gifu B-129, respectively. The number of probe sets differentially expressed in roots was higher than that of shoots, regardless the ecotype. Gifu B-129 and MG-20 also differed in their regulation of genes that could play important roles in the generation of a new Fe/Zn homeostatic cellular condition, synthesis of plant compounds involved in stress response, protein-degradation, damage repair and root senescence, as well as in glycolysis, gluconeogenesis and TCA. In addition, there were differences between both ecotypes in the expression patterns of putative transcription factors that could determine distinct arrangements of flavonoid and isoflavonoid compounds. Our results provided a set of selected, differentially expressed genes deserving further investigation and suggested that the L. japonicus ecotypes could constitute a useful model to search for common and distinct tolerance mechanisms to long-term alkaline stress response in plants. PMID:24835559

Metabolic responses to Wii Fit™ video games at different game levels.

PubMed

Worley, Jennifer R; Rogers, Sharon N; Kraemer, Robert R

2011-03-01

The Wii Fit™ is a form of interactive gaming designed to elicit health and fitness benefits to replace sedentary gaming. This study was designed to determine the effectiveness of Wii Fit™ fitness games. The purpose of the study was to determine the %VO2max and energy expenditure from different Wii Fit™ games at different levels including the step and hula games. Eight healthy young women completed a preliminary trial to determine VO2max and later played the Wii Fit™ during 2 separate counterbalanced trials. During each session, subjects played levels of Wii Fit™ games for 10 minutes each level. One session involved beginning and intermediate hula, and the other session involved beginning and intermediate steps. The VO2 was measured continuously via metabolic cart, and rating of perceived exertion (RPE) was assessed at the end of each game level. The lowest %VO2max, kcal·min, and RPE occurred during the beginning step game and the highest values occurred during the intermediate hula game. Respiratory exchange ratio was significantly higher in the intermediate hula than beginning hula game but was not significantly different between step game levels. The intermediate hula and step games produced the greatest energy expenditure with an equivalent effect of a walking speed of >5.63 km·h (>3.5 miles·h). This is the first study to determine the percentage of VO2max and caloric expenditure elicited by different Wii Fit™ video games at different game levels in adults. Findings suggest that the Wii Fit™ can be used as an effective activity for promoting physical health in this population.

Stress and Achievement of Cardiovascular Health Metrics: The American Heart Association Life's Simple 7 in Blacks of the Jackson Heart Study.

PubMed

Brewer, LaPrincess C; Redmond, Nicole; Slusser, Joshua P; Scott, Christopher G; Chamberlain, Alanna M; Djousse, Luc; Patten, Christi A; Roger, Veronique L; Sims, Mario

2018-06-05

Ideal cardiovascular health metrics (defined by the American Heart Association Life's Simple 7 [LS7]) are suboptimal among blacks, which results in high risk of cardiovascular disease. We examined the association of multiple stressors with LS7 components among blacks. Using a community-based cohort of blacks (N=4383), we examined associations of chronic stress, minor stressors, major life events, and a cumulative stress score with LS7 components (smoking, diet, physical activity, body mass index, blood pressure, total cholesterol, and fasting plasma glucose) and an LS7 composite score. Multivariable logistic regression assessed the odds of achieving intermediate/ideal levels of cardiovascular health adjusted for demographic, socioeconomic, behavioral, and biomedical factors. The LS7 components with the lowest percentages of intermediate/ideal cardiovascular health levels were diet (39%), body mass index (47%), and physical activity (51%). Higher chronic, minor, and cumulative stress scores were associated with decreased odds (odds ratio [OR]) of achieving intermediate/ideal levels for smoking (OR [95% confidence interval], 0.80 [0.73-0.88], 0.84 [0.75-0.94], and 0.81 [0.74-0.90], respectively). Participants with more major life events had decreased odds of achieving intermediate/ideal levels for smoking (OR, 0.84; 95% confidence interval, 0.76-0.92) and fasting plasma glucose (OR, 0.90; 95% confidence interval, 0.82-0.98). Those with higher scores for minor stressors and major life events were less likely to achieve intermediate or ideal LS7 composite scores (OR [95% confidence interval], 0.89 [0.81-0.97] and 0.91 [0.84-0.98], respectively). Blacks with higher levels of multiple stress measures are less likely to achieve intermediate or ideal levels of overall cardiovascular health (LS7 composite score), specific behaviors (smoking), and biological factors (fasting plasma glucose). © 2018 The Authors and Mayo Clinic. Published on behalf of the American Heart Association, Inc., by Wiley.

CHARACTERIZATION OF ACTINIDES IN SIMULATED ALKALINE TANK WASTE SLUDGES AND LEACHATES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nash, Kenneth L.

In this project, both the fundamental chemistry of actinides in alkaline solutions (relevant to those present in Hanford-style waste storage tanks), and their dissolution from sludge simulants (and interactions with supernatants) have been investigated under representative sludge leaching procedures. The leaching protocols were designed to go beyond conventional alkaline sludge leaching limits, including the application of acidic leachants, oxidants and complexing agents. The simulant leaching studies confirm in most cases the basic premise that actinides will remain in the sludge during leaching with 2-3 M NaOH caustic leach solutions. However, they also confirm significant chances for increased mobility of actinidesmore » under oxidative leaching conditions. Thermodynamic data generated improves the general level of experiemental information available to predict actinide speciation in leach solutions. Additional information indicates that improved Al removal can be achieved with even dilute acid leaching and that acidic Al(NO3)3 solutions can be decontaminated of co-mobilized actinides using conventional separations methods. Both complexing agents and acidic leaching solutions have significant potential to improve the effectiveness of conventional alkaline leaching protocols. The prime objective of this program was to provide adequate insight into actinide behavior under these conditions to enable prudent decision making as tank waste treatment protocols develop.« less

Effect of alkali on the structure of cell envelopes of Chlamydia psittaci elementary bodies.

PubMed Central

Narita, T; Wyrick, P B; Manire, G P

1976-01-01

Suspensions of isolated cell envelopes of infectious elementary bodies (EB) of Chlamydia psittaci at alkaline pH showed a rapid, extensive decrease in absorbance, accompanied by the release of a cell envelope component in a sedimentable form. This phenomenon was observed both at 0 C and with envelopes which had been previously heated to 100 C. Monovalent and divalent cations effectively inhibited the turbidity loss, whereas ethylenediaminetetraacetate (EDTA) caused an accelerated decrease in turbidity. The turbidity loss observed after incubation of the envelopes at alkaline pH could be reversed to the level of the initial value by dialysis against distilled water containing Mg2+. Thin-section electron photomicrographs of purified EB exposed to alkaline buffer with EDTA revealed the loss of the internal contents of cells, but these cells still maintained their round shapes. The cell surface of treated EB appeared pitted in negatively stained preparations, whereas intact EB had a smooth surface. Electron microscopic studies on negatively stained preparations of the clear supernatant obtained after the treatment of the envelope with alkaline buffer containing EDTA demonstrated the presence of spherical particles, approximately 6 to 7 nm in diameter, and rodlike particles, which appeared to be made up of two or more spherical particles. Images PMID:1375

The High Level of Aluminum Resistance in Signalgrass Is Not Associated with Known Mechanisms of External Aluminum Detoxification in Root Apices1

PubMed Central

Wenzl, Peter; Patiño, Gloria M.; Chaves, Alba L.; Mayer, Jorge E.; Rao, Idupulapati M.

2001-01-01

Al resistance of signalgrass (Brachiaria decumbens Stapf cv Basilisk), a widely sown tropical forage grass, is outstanding compared with the closely related ruzigrass (Brachiaria ruziziensis Germain and Evrard cv Common) and Al-resistant genotypes of graminaceous crops such as wheat, triticale, and maize. Secretion of organic acids and phosphate by root apices and alkalinization of the apical rhizosphere are commonly believed to be important mechanisms of Al resistance. However, root apices of signalgrass secreted only moderately larger quantities of organic acids than did those of ruzigrass, and efflux from signalgrass apices was three to 30 times smaller than from apices of Al-resistant genotypes of buckwheat, maize, and wheat (all much more sensitive to Al than signalgrass). In the presence, but not absence, of Al, root apices of signalgrass alkalinized the rhizosphere more than did those of ruzigrass. The latter was associated with a shortening of the alkalinizing zone in Al-intoxicated apices of ruzigrass, indicating that differences in alkalinizing power were a consequence, not a cause of, differential Al resistance. These data indicate that the main mechanism of Al resistance in signalgrass does not involve external detoxification of Al. Therefore, highly effective resistance mechanisms based on different physiological strategies appear to operate in this species. PMID:11244126

Treatment of cells with alkaline borate buffer extends the capability of interphase FISH mapping.

PubMed

Yokota, H; van den Engh, G; Mostert, M; Trask, B J

1995-01-20

Interphase fluorescence in situ hybridization (FISH) has been shown to be a means to map DNA sequences relative to each other in the 100 kb to 1-2 Mb genomic-separation range. At distances below 0.1 Mb, probe sites are infrequently resolved in interphase chromatin. In the 0.1- to 1-Mb range, interphase chromatin can be modeled as a freely flexible chain. The mean square interphase distance between two probes is proportional to the genomic separation between the probes on the linear DNA molecule. Above 1-2 Mb, the relationship between interphase distance and genomic separation changes abruptly and appears to level off. We have used alkaline-borate treatment to expand the capability of interphase FISH mapping. We show here that alkaline-borate treatment increases nuclear diameter, the interphase distance between probes on homologous chromosomes, and the distance between probes on the same chromosome. We also show that the mean square distance between hybridization sites in borate-treated nuclei is proportional to genomic separation up to 4 Mb. Thus, alkaline-borate treatment enhances the capability of interphase FISH mapping by increasing the absolute distance between probes and extending the range of the simple relationship between interphase distance and genomic separation.

Treatment of cells with alkaline borate buffer extends the capability of interphase FISH mapping

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yokota, H.; Van Den Engh, G.; Mostert, M.

1995-01-20

Interphase fluorescence in situ hybridization (FISH) has been shown to be a means to map DNA sequences relative to each other in the 100 kb to 1-2 Mb genomic-separation range. At distances below 0.1 Mb, probe sites are infrequently resolved in interphase chromatin. In the 0.1- to 1-Mb range, interphase chromatin can be modeled as a freely flexible chain. The mean square interphase distance between two probes is proportional to the genomic separation between the probes on the linear DNA molecule. Above 1-2 Mb, the relationship between interphase distance and genomic separation changes abruptly and appears to level off. Wemore » have used alkaline-borate treatment to expand the capability of interphase FISH mapping. We show here that alkaline-borate treatment increases nuclear diameter, the interphase distance between probes on homologous chromosomes, and the distance between probes on the same chromosome. We also show that the mean square distance between hybridization sites in borate-treated nuclei is proportional to genomic separation up to 4 Mb. Thus, alkaline-borate treatment enhances the capability of interphase FISH mapping by increasing the absolute distance between probes and extending the range of the simple relationship between interphase distance and genomic separation. 31 refs., 5 figs.« less

Seeking effective dyes for a mediated glucose-air alkaline battery/fuel cell

NASA Astrophysics Data System (ADS)

Eustis, Ross; Tsang, Tsz Ming; Yang, Brigham; Scott, Daniel; Liaw, Bor Yann

2014-02-01

A significant level of power generation from an abiotic, air breathing, mediated reducing sugar-air alkaline battery/fuel cell has been achieved in our laboratories at room temperature without complicated catalysis or membrane separation in the reaction chamber. Our prior studies suggested that mass transport limitation by the mediator is a limiting factor in power generation. New and effective mediators were sought here to improve charge transfer and power density. Forty-five redox dyes were studied to identify if any can facilitate mass transport in alkaline electrolyte solution; namely, by increasing the solubility and mobility of the dye, and the valence charge carried per molecule. Indigo dyes were studied more closely to understand the complexity involved in mass transport. The viability of water-miscible co-solvents was also explored to understand their effect on solubility and mass transport of the dyes. Using a 2.0 mL solution, 20% methanol by volume, with 100 mM indigo carmine, 1.0 M glucose and 2.5 M sodium hydroxide, the glucose-air alkaline battery/fuel cell attained 8 mA cm-2 at short-circuit and 800 μW cm-2 at the maximum power point. This work shall aid future optimization of mediated charge transfer mechanism in batteries or fuel cells.

Effect of alkalinity on nitrite accumulation in treatment of coal chemical industry wastewater using moving bed biofilm reactor.

PubMed

Hou, Baolin; Han, Hongjun; Jia, Shengyong; Zhuang, Haifeng; Zhao, Qian; Xu, Peng

2014-05-01

Nitrogen removal via nitrite (the nitrite pathway) is more suitable for carbon-limited industrial wastewater. Partial nitrification to nitrite is the primary step to achieve nitrogen removal via nitrite. The effect of alkalinity on nitrite accumulation in a continuous process was investigated by progressively increasing the alkalinity dosage ratio (amount of alkalinity to ammonia ratio, mol/mol). There is a close relationship among alkalinity, pH and the state of matter present in aqueous solution. When alkalinity was insufficient (compared to the theoretical alkalinity amount), ammonia removal efficiency increased first and then decreased at each alkalinity dosage ratio, with an abrupt removal efficiency peak. Generally, ammonia removal efficiency rose with increasing alkalinity dosage ratio. Ammonia removal efficiency reached to 88% from 23% when alkalinity addition was sufficient. Nitrite accumulation could be achieved by inhibiting nitrite oxidizing bacteria (NOB) by free ammonia (FA) in the early period and free nitrous acid in the later period of nitrification when alkalinity was not adequate. Only FA worked to inhibit the activity of NOB when alkalinity addition was sufficient. Copyright © 2014 The Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

Show Me the Mush! - Constraints From Voluminous Rhyolitic Ignimbrites of Bimodal and Calc-alkaline Settings on the Applicability of a Mush Model

NASA Astrophysics Data System (ADS)

Streck, M. J.

2012-12-01

Mush models have been popular in explaining crystal-poor rhyolites of a variety of settings. The classical mush model requires an abundance of very crystal-rich (>50%), intermediate (dacitic) magmas that upon compaction expel their interstitial liquids that erupt to give rise to rhyolitic lava flows and ignimbrites. In volcanic systems, a critical part in evaluating a mush model rests on providing evidence for the existence of suitable crystal-rich intermediate magmas that are consistent with the petrology of the erupted rhyolites. In my evaluation, I focus on providing constraints of whether or not suitable crystal mushes are likely to have existed and were instrumental in the production of a select series of voluminous (>100 km3) rhyolitic ignimbrites. Furthermore, the volcanic framework of each selected ignimbrite is used for assessing questions of "eruptibility" of magma types. The three main evaluated units representing 'hot-dry-reduced' rhyolites of bimodal settings are the 16-15.4 Ma Dinner Creek Tuff, the 9.7 Ma Devine Canyon Tuff, and 7.1 Ma Rattlesnake Tuff. All three tuffs erupted in eastern Oregon within a basalt-rhyolite suite. The key feature that makes them particularly valuable for this discussion is that each of the tuffs erupted a co-magmatic component that tracks the intermediate to mafic underpinnings to the rhyolitic magma. This allows a direct assessment of what intermediate magmas residing in close spatial proximity to the rhyolites looked like. On the other hand, other characteristics such as degree of chemical zoning, element trends, single or multiple cooling units, etc., vary considerably among the three tuffs thus covering a wide spectrum of rhyolites from bimodal settings. As representative of 'cool-wet-oxidized' rhyolites, I test applicability of the mush model on the tuffs and associated lavas of the Oligocene San Luis caldera system. This system represents strongly confocal and voluminous eruptions that are closely spaced in time at the end of the activity period of the Central Caldera Cluster of the Oligocene San Juan volcanic field, Colorado. Compositional intermediate underpinnings of each of the 'hot-dry-reduced' rhyolites fail geochemical requirements to represent suitable intermediate magmas. In addition, these underpinnings are crystal-poor and this is inconsistent with the required high crystallinity of magma mushes. Remelting scenarios to reduce crystallinities in intermediate magmas are excluded - again on geochemical grounds. Other complications with a model of voluminous crystal mushes beneath such rhyolites are the production of strong trace-element chemical gradation within single magma batches as well as multi-cyclic eruptions of crystal-poor rhyolites from the same system. For the system of 'cold-wet-oxidized' rhyolites, one of the challenges for a mush model is that interstitial melts of crystal-rich intermediate magmas compositionally deviate from erupted rhyolites when abundant amphibole (±sphene) is present, yet both phases are commonly expected phenocrystic phases at crystallinities when extraction of rhyolite from mush can take place.

Health Effects of Alkaline Diet and Water, Reduction of Digestive-tract Bacterial Load, and Earthing.

PubMed

Mousa, Haider Abdul-Lateef

2016-04-01

In the article, the author discusses the issue of chronic, low-grade acidosis that is thought to be brought about primarily by 2 factors: (1) advancing age, with a consequent decline in renal function; and (2) diet. An acid-forming diet can induce low-grade metabolic acidosis, which causes very small decreases in blood pH and plasma bicarbonate (HCO3-) that remain within the range considered to be normal. However, if the duration of the acidosis is prolonged or chronically present, even a low degree of acidosis can become significant. This article reviews supporting evidence in the literature that has shown that consumption of abundant alkaline-forming foods can result in improvement in bone mineral density (BMD) and muscle mass, protection from chronic illnesses, reduced tumor-cell invasion and metastasis, and effective excretion of toxins from the body. In addition, a large number of studies showing the benefits of alkaline water (mineral water) have revealed that people consuming water with a high level of total dissolved solids (TDS) (ie, with a high mineral content) have shown a lower incidence of coronary heart disease (CHD), cardiovascular disease (CVD), and cancer and lower total mortality rates. Consumption of alkaline water also may prevent osteoporosis and protect pancreatic beta cells with its antioxidant effects. In addition, this article discusses the literature that shows that reducing digestive-tract bacterial load can play an important role in increasing blood alkalinity toward the normal upper limit. That change occurs through good oral hygiene, flossing of teeth, perfect chewing of food, and bowel evacuation as soon as possible. Finally, the author reviews the literature that shows that earthing (ie, the direct contact of the human body with the earth) can supply a current of plentiful electrons. Earthing has been shown to reduce acute and chronic inflammation, blood glucose in patients with diabetes, red blood cell (RBC) aggregation, and blood coagulation. It also has been shown to produce symptomatic improvement in chronic, muscle and joint pain, a reduction in overall stress levels and tensions, a boost in positive moods, an improvement in heart rate variability, and an improvement in the immune response.

Two-photon absorption by spectrally shaped entangled photons

NASA Astrophysics Data System (ADS)

Oka, Hisaki

2018-03-01

We theoretically investigate two-photon excitation by spectrally shaped entangled photons with energy anticorrelation in terms of how the real excitation of an intermediate state affects two-photon absorption by entangled photons. Spectral holes are introduced in the entangled photons around the energy levels of an intermediate state so that two-step excitation via the real excitation of the intermediated state can be suppressed. Using a three-level atomic system as an example, we show that the spectral holes well suppress the real excitation of the intermediate state and recover two-photon absorption via a virtual state. Furthermore, for a short pulse close to a monocycle, we show that the excitation efficiency by the spectrally shaped entangled photons can be enhanced a thousand times as large as that by uncorrelated photons.

Reactivity of bacterial and fungal laccases with lignin under alkaline conditions.

PubMed

Moya, Raquel; Saastamoinen, Päivi; Hernández, Manuel; Suurnäkki, Anna; Arias, Enriqueta; Mattinen, Maija-Liisa

2011-11-01

The ability of Streptomyces ipomoea laccase to polymerize secoisolariciresinol lignan and technical lignins was assessed. The reactivity of S. ipomoea laccase was also compared to that of low redox fungal laccase from Melanocarpus albomyces using low molecular mass p-coumaric, ferulic and sinapic acid as well as natural (acetosyringone) and synthetic 2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPO) mediators as substrates. Oxygen consumption measurement, MALDI-TOF MS and SEC were used to follow the enzymatic reactions at pH 7, 8, 9 and 10 at 30°C and 50°C. Polymerization of lignins and lignan by S. ipomoea laccase under alkaline reaction conditions was observed, and was enhanced in the presence of acetosyringone almost to the level obtained with M. albomyces laccase without mediator. Reactivities of the enzymes towards acetosyringone and TEMPO were similar, suggesting exploitation of the compounds and low redox laccase in lignin valorization under alkaline conditions. The results have scientific impact on basic research of laccases. Copyright © 2011 Elsevier Ltd. All rights reserved.

Study on application of polyenzyme method to offal of Harengula zunasi

NASA Astrophysics Data System (ADS)

Deng, Shanggui; Yang, Ping; Xia, Xingzhou

2003-12-01

The new polyenzyme method for making gravy from Harengula zunasi offal involves protein enzymolysis with flavorase after proper alkaline and neutral protease levels were established by orthogonal trials to select the best hydrolytic conditions for processing offal with alkaline and neutral protease. The conditions for the polyenzyme method were pH of 7.0, temperature of 50°C, alkaline and neutral protease concentration of 1.5% respectively, hydrolysis time of 120 min, and flavorase concentration of 2.0%, for 60 min. The new gravy-making technology yields a nutritious and delicious gravy containing 40.3% of total essential amino acids, with delicious amino acids Glu, Asp, Gly, Ala, Pro and Ser comprising 49.5%, total and amino nitrogen being respectively 1.9 and 1.1 g/100 g (amino acid nitrogen being 61.0% of total nitrogen), The polyenzyme method was used to make 14.8% protein gravy from Harengula zunasi offal. In addition, inorganic elements, the phosphorus content is the highest.

Metabolic Capabilities of the Members of the Order Halanaerobiales and Their Potential Biotechnological Applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Roush, Daniel W; Elias, Dwayne A; Mormile, Dr. Melanie R.

The order Halanaerobiales contains a number of well-studied halophiles that possess great potential for biotechnological applications. The unique halophilic adaptations that these organisms utilize, such as salting-in mechanisms to increase their intercellular concentration of KCl, combined with their ability to ferment simple sugars, provides an excellent platform for biotechnological development over a wide range of salt levels and possible other extreme conditions, such as alkaline conditions. From fermented foods to oil reservoirs, members of Halanaerobiales are found in many environments. The environmental conditions many of these organisms grow are similar to industrially important processes, such as alkaline pre-treated biomass stocks,more » treatment of crude glycerol from biodiesel production, salty fermented foods, as well as bioremediation of contaminants under extreme conditions of salinity and in some cases, alkalinity. From salt stable enzymes to waste fermentations, bioremediation options, bioenergy, and microbially enhanced oil recovery (MEOR), Halanaerobiales can provide a wide spectrum of environmentally friendly solutions to current problems.« less

Intestinal alkaline phosphatase detoxifies lipopolysaccharide and prevents inflammation in zebrafish in response to the gut microbiota.

PubMed

Bates, Jennifer M; Akerlund, Janie; Mittge, Erika; Guillemin, Karen

2007-12-13

Vertebrates harbor abundant lipopolysaccharide (LPS) in their gut microbiota. Alkaline phosphatases can dephosphorylate and detoxify the endotoxin component of LPS. Here, we show that expression of the zebrafish intestinal alkaline phosphatase (Iap), localized to the intestinal lumen brush border, is induced during establishment of the gut microbiota. Iap-deficient zebrafish are hypersensitive to LPS toxicity and exhibit the excessive intestinal neutrophil influx characteristic of wild-type zebrafish exposed to LPS. Both of these Iap mutant phenotypes are dependent on Myd88 and Tumor Necrosis Factor Receptor (Tnfr), proteins also involved in LPS sensitivity in mammals. When reared germ-free, the intestines of Iap-deficient zebrafish are devoid of neutrophils. Together, these findings demonstrate that the endogenous microbiota establish the normal homeostatic level of neutrophils in the zebrafish intestine through a process involving Iap, Myd88, and Tnfr. Thus, by preventing inflammatory responses, Iap plays a crucial role in promoting mucosal tolerance to resident gut bacteria.

Reformation of casein particles from alkaline-disrupted casein micelles.

PubMed

Huppertz, Thom; Vaia, Betsy; Smiddy, Mary A

2008-02-01

In this study, the properties of casein particles reformed from alkaline disrupted casein micelles were studied. For this purpose, micelles were disrupted completely by increasing milk pH to 10.0, and subsequently reformed by decreasing milk pH to 6.6. Reformed casein particles were smaller than native micelles and had a slightly lower zeta-potential. Levels of ionic and serum calcium, as well as rennet coagulation time did not differ between milk containing native micelles or reformed casein particles. Ethanol stability and heat stability, >pH 7.0, were lower for reformed casein particles than native micelles. Differences in heat stability, ethanol stability and zeta-potential can be explained in terms of the influence of increased concentrations of sodium and chloride ions in milk containing reformed casein particles. Hence, these results indicate that, if performed in a controlled manner, casein particles with properties closely similar to those of native micelles can be reformed from alkaline disrupted casein micelles.

CO2-Free Power Generation on an Iron Group Nanoalloy Catalyst via Selective Oxidation of Ethylene Glycol to Oxalic Acid in Alkaline Media

NASA Astrophysics Data System (ADS)

Matsumoto, Takeshi; Sadakiyo, Masaaki; Ooi, Mei Lee; Kitano, Sho; Yamamoto, Tomokazu; Matsumura, Syo; Kato, Kenichi; Takeguchi, Tatsuya; Yamauchi, Miho

2014-07-01

An Fe group ternary nanoalloy (NA) catalyst enabled selective electrocatalysis towards CO2-free power generation from highly deliverable ethylene glycol (EG). A solid-solution-type FeCoNi NA catalyst supported on carbon was prepared by a two-step reduction method. High-resolution electron microscopy techniques identified atomic-level mixing of constituent elements in the nanoalloy. We examined the distribution of oxidised species, including CO2, produced on the FeCoNi nanoalloy catalyst in the EG electrooxidation under alkaline conditions. The FeCoNi nanoalloy catalyst exhibited the highest selectivities toward the formation of C2 products and to oxalic acid, i.e., 99 and 60%, respectively, at 0.4 V vs. the reversible hydrogen electrode (RHE), without CO2 generation. We successfully generated power by a direct EG alkaline fuel cell employing the FeCoNi nanoalloy catalyst and a solid-oxide electrolyte with oxygen reduction ability, i.e., a completely precious-metal-free system.

Effectiveness of the addition of alkaline materials at surface coal mines in preventing or abating acid mine drainage--Part 2. Mine site case studies

USGS Publications Warehouse

Brady, Keith; Smith, Michael W.; Beam, Richard L.; Cravotta,, Charles A.

1990-01-01

The effectiveness of preventing or ameliorating acid mine drainage (AMD) through the application of alkaline additives is evaluated for eight surface coal mines in Pennsylvania. Many of the mine sites had overburden characteristics that made prediction of post‐mining water quality uncertain. Alkaline materials were applied at rates ranging from 42 to greater than 1,000 tons as calcium carbonate per acre. In addition, two sites that were mined and reclaimed without alkaline additives are included for comparative purposes. Overburden sulfur concentration and "neutralization potential" (NP) data for multiple strata at each mine site were used to compute the cumulative, mass‐weighted "maximum potential acidity" (MPA) and "net neutralization potential" (NNP = NP ‐ MPA) by using three different calculation methods. Post‐reclamation water‐quality data were used to compute the net alkalinity (= alkalinity ‐ acidity). The most conservative determination of NNP, whereby MPA is calculated by multiplying the total sulfur concentration, in weight percent, by 62.5 instead of 31.25, yielded the best agreement with net alkalinity (patching signs on NNP and net alkalinity). The error in prediction using each method was that the reclaimed overburden was computed to be alkaline overall (NNP > 0), but the post‐reclamation water was acid (net alkalinity < 0). In general, alkaline addition rates were probably insufficient to neutralize, or too late to prevent, acid production in the mine spoil. At six of the seven mine sites that had overburden with insufficient NP relative to MPA (NNP < 0), the addition of alkaline materials failed to create alkaline mine drainage; AMD was formed or persisted. A control site which also had insufficient alkaline material, but did not incorporate alkaline additives, generated severe AMD. Two sites that had substantial, natural alkaline overburden produced alkaline drainage. Although the addition rates appear to be inadequate, other factors, such as unequal distribution and exposure of the acid‐forming or neutralizing materials and hydrogeological variability, complicate the evaluation of relative effectiveness of using different alkaline materials and placement of the acid‐ or alkaline‐producing materials.

The high mobility group protein Abf2p influences the level of yeast mitochondrial DNA recombination intermediates in vivo.

PubMed

MacAlpine, D M; Perlman, P S; Butow, R A

1998-06-09

Abf2p is a high mobility group (HMG) protein found in yeast mitochondria that is required for the maintenance of wild-type (rho+) mtDNA in cells grown on fermentable carbon sources, and for efficient recombination of mtDNA markers in crosses. Here, we show by two-dimensional gel electrophoresis that Abf2p promotes or stabilizes Holliday recombination junction intermediates in rho+ mtDNA in vivo but does not influence the high levels of recombination intermediates readily detected in the mtDNA of petite mutants (rho-). mtDNA recombination junctions are not observed in rho+ mtDNA of wild-type cells but are elevated to detectable levels in cells with a null allele of the MGT1 gene (Deltamgt1), which codes for a mitochondrial cruciform-cutting endonuclease. The level of recombination intermediates in rho+ mtDNA of Deltamgt1 cells is decreased about 10-fold if those cells contain a null allele of the ABF2 gene. Overproduction of Abf2p by >/= 10-fold in wild-type rho+ cells, which leads to mtDNA instability, results in a dramatic increase in mtDNA recombination intermediates. Specific mutations in the two Abf2p HMG boxes required for DNA binding diminishes these responses. We conclude that Abf2p functions in the recombination of rho+ mtDNA.

The effects of tissue-non-specific alkaline phosphatase gene therapy on craniosynostosis and craniofacial morphology in the FGFR2C342Y/+ mouse model of Crouzon craniosynostosis.

PubMed

Wang, E; Nam, H K; Liu, J; Hatch, N E

2015-04-01

Craniosynostosis, the premature fusion of cranial bones, has traditionally been described as a disease of increased bone mineralization. However, multiple mouse models of craniosynostosis display craniosynostosis simultaneously with diminished cranial bone volume and/or density. We propose an alternative hypothesis that craniosynostosis results from abnormal tissue mineralization through the downregulation of tissue-non-specific alkaline phosphatase (TNAP) enzyme downstream of activating mutations in FGFRs. Neonatal Crouzon (FGFRC342Y/+) and wild-type (FGFR+/+) mice were injected with lentivirus to deliver a recombinant form of TNAP. Mice were sacrificed at 4 weeks postnatal. Serum was collected to test for alkaline phosphatase (AP), phosphorus, and calcium levels. Craniofacial bone fusion and morphology were assessed by micro-computed tomography. Injection with the TNAP lentivirus significantly increased serum AP levels (increased serum AP levels are indicative of efficient transduction and production of the recombinant protein), but results were variable and dependent upon viral lot and the litter of mice injected. Morphological analysis revealed craniofacial form differences for inferior surface (p=0.023) and cranial height (p=0.014) regions between TNAP lentivirus-injected and vehicle-injected Crouzon mice. With each unit increase in AP level, the odds of lambdoid suture fusion decreased by 84.2% and these results came close to statistical significance (p=0.068). These results suggest that TNAP deficiency may mediate FGFR2-associated craniosynostosis. Future studies should incorporate injection of recombinant TNAP protein, to avoid potential side effects and variable efficacy of lentiviral gene delivery. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Low frequency vibrational spectra and the nature of metal-oxygen bond of alkaline earth metal acetylacetonates

NASA Astrophysics Data System (ADS)

Fakheri, Hamideh; Tayyari, Sayyed Faramarz; Heravi, Mohammad Momen; Morsali, Ali

2017-12-01

Theoretical quantum chemistry calculations were used to assign the observed vibrational band frequencies of Be, Mg, Ca, Sr, and Ba acetylacetonates complexes. Density functional theory (DFT) calculations have been carried out at the B3LYP level, using LanL2DZ, def2SVP, and mixed, GenECP, (def2SVP for metal ions and 6-311++G** for all other atoms) basis sets. The B3LYP level, with mixed basis sets, was utilized for calculations of vibrational frequencies, IR intensity, and Raman activity. Analysis of the vibrational spectra indicates that there are several bands which could almost be assigned mainly to the metal-oxygen vibrations. The strongest Raman band in this region could be used as a measure of the stability of the complex. The effects of central metal on the bond orders and charge distributions in alkaline earth metal acetylacetonates were studied by the Natural Bond Orbital (NBO) method for fully optimized compounds. Optimization were performed at the B3LYP/6-311++G** level for the lighter alkaline earth metal complexes (Be, Mg, and Ca acetylacetonates) while the B3LYP level, using LanL2DZ (extrabasis, d and f on oxygen and metal atoms), def2SVP and mixed (def2SVP on metal ions and 6-311++G** for all other atoms) basis sets for all understudy complexes. Calculations indicate that the covalence nature of metal-oxygen bonds considerably decreases from Be to Ba complexes. The nature of metal-oxygen bond was further studied by using Atoms In Molecules (AIM) analysis. The topological parameters, Wiberg bond orders, natural charges of O and metal ions, and also some vibrational band frequencies were correlated with the stability constants of understudy complexes.

Acid and Alkaline Phosphatase Levels in GCF during Orthodontic Tooth Movement

PubMed Central

Farahani, Mohammad; Safavi, Seyed Mohammadreza; Dianat, Omid; Khoramian Tusi, Somayeh; Younessian, Farnaz

2015-01-01

Statement of the Problem The present constituents of gingival crevicular fluid (GCF) can reflect the changes occurring in underlying tissues. Considering variety of biologic bone markers, alkaline phosphatase and acid phosphatase have been examined as bone turn over markers in orthodontic tooth movement. Purpose The current study designed in a longitudinal pattern to determine the changes of acid and alkaline phosphatase (ACP & ALP) in GCF during orthodontic tooth movement. Materials and Method An upper canines from twelve patients (mean age: 14±2 years) undergoing extraction orthodontic treatment for distal movement served as the test tooth (DC), and its contralateral (CC) and antagonist (AC) canines were used as controls. The CC was included in orthodontic appliance without orthodontic force; the AC was free from any orthodontic appliance. The GCF around the experimental teeth was harvested from mesial and distal tooth sites immediately before appliance placement (T0), and 14 (T2) and 28 days (T3) after it and ALP and ACP concentration were determined spectrophotometrically. Results ALP concentration was elevated significantly in DC and CC groups at days 14 and 28 compared with the AC. In DC group, the ALP was significantly greater in mesial sites than distal site, while no significant changes were found between both sites of CC. The peak level of ALP was observed in mesial sites of DC at T2. Regarding ACP, significant elevation of this enzyme was seen in DC group both in mesial and distal sites at T2 and T3. The peak level of this enzyme was seen at T2. Conclusion Monitoring simultaneous changes of ALP and ACP levels in GCF can reflect the tissue responses occur in periodontium during bone formation and bone resorption during orthodontic tooth movement, respectively. PMID:26535403

Attitudes of the Preparatory Class Students towards the Writing Course and Their Attitude-Success Relationship in Writing

ERIC Educational Resources Information Center

Paker, Turan; Erarslan, Ali

2015-01-01

This study aims to explore the attitudes of Turkish EFL students towards the writing course at university and to investigate the relationship between students' attitudes and their overall proficiency in writing. The participants were 782 students from various departments in the pre-intermediate, intermediate and upper-intermediate levels in a…

The Impact of the Principles of Accounting Experience on Student Preparation for Intermediate Accounting

ERIC Educational Resources Information Center

Carrington, Linda G.

2012-01-01

Both students and instructors alike will generally agree that intermediate accounting courses are among the most difficult and demanding in an accounting or finance curriculum, and perhaps even on the college campus. Intermediate accounting contains subject matter which requires a higher level of thinking and a greater ability to process prior…

Acidified seawater increases accumulation of cobalt but not cesium in manila clam Ruditapes philippinarum.

PubMed

Sezer, Narin; Kocaoğlan, Hasan Oğuz; Kılıç, Önder; Lacoue-Labarthe, Thomas; Belivermiş, Murat

2018-04-01

The pH of seawater around the world is expected to continue its decline in the near future in response to ocean acidification that is driven by heightened atmospheric CO 2 emissions. Concomitantly, economically-important molluscs that live in coastal waters including estuaries and embayments, may be exposed to a wide assortment of contaminants, including trace metals and radionuclides. Seawater acidification may alter both the chemical speciation of select elements as well as the physiology of organisms, and may thus pose at risk to many shellfish species, including the manila clam Ruditapes philippinarum. The bioconcentration efficiency of two common radionuclides associated with the nuclear fuel cycle, 134 Cs and 57 Co, were investigated by exposing live clams to dissolved 134 Cs and 57 Co at control (pH = 8.1) and two lowered pH (pH = 7.8 and 7.5) levels using controlled aquaria. The uptake and depuration kinetics of the two radionuclides in the whole-body clam were followed for 21 and 35 days, respectively. At steady-state equilibrium, the concentration factor (CF ss ) for 57 Co increased as the pH decreased (i.e. 130 ± 5, 194 ± 6, and 258 ± 10 at pH levels 8.1, 7.8 and 7.5, respectively), whereas the 134 Cs uptake was not influenced by a change in pH conditions. During depuration, the lowest depuration rate constant of 57 Co by the manila clam was observed at the intermediate pH of 7.8. An increase in the accumulation of 57 Co at the intermediate pH value was thought to be caused mainly by the aragonitic shell of the clam, as well as the low salinity and alkalinity of seawater used in the experiment. Considering that accumulation consists of uptake and depuration, among the three pH conditions moderately acidified seawater enhanced most the accumulation of 57 Co. Accumulation of 134 Cs was not strongly influenced by a reduced pH condition, as represented by an analogous uptake constant rate and CF ss in each treatment. Such results suggest that future seawater pH values that are projected to be lower in the next decades, may pose a risk for calcium-bearing organisms such as shellfish. Copyright © 2018. Published by Elsevier Ltd.

Petrogenesis and tectonic significance of the calc-alkaline, bimodal Aztec Wash pluton, Eldorado Mountains, Colorado River extensional corridor

NASA Astrophysics Data System (ADS)

Falkner, Claudia M.; Miller, Calvin F.; Wooden, Joseph L.; Heizler, Matthew T.

1995-06-01

The 15.7 Ma Aztec Wash pluton is located in the central Eldorado Mountains of the Colorado River extensional corridor in southern Nevada, immediately south of the well-known imbricated volcanic sequence that has been widely cited in studies of extensional tectonism (e.g., Anderson, 1971). It is a shallow level (≤5 km), essentially bimodal complex, primarily made up of granite (˜72 wt % SiO2) and diabase and diorite (˜54 wt % SiO2), with minor amounts of more mafic, intermediate, and highly evolved rocks. The mafic and felsic magmas mingled extensively but mixed only to a limited extent. Late synplutonic mafic and felsic dikes represent continuing injection of the same bimodal magmas. The mafic rocks have high incompatible element concentrations (e.g., K2O ˜ 3 wt %, Ba ˜ 1600 ppm, light rare earth elements 350 × chondrite) and enriched isotopic compositions (ɛNd -7.5, 87Sr/86Sr 0.708); generation in ancient, enriched mantle lithosphere with limited subsequent crustal contamination is inferred. The granite is more potassic (˜5 wt %) than the mafic rocks, but it has comparable or lower concentrations of most incompatible elements; its isotopic composition (ɛNd -10, 87Sr/86Sr 0.710) is intermediate between those of the mafic rocks and local ancient crust. The granites thus indicate hybridization of the crust by mafic magma, but it is unclear whether this hybridization occurred at deeper levels in this magmatic system, or during an earlier mid-Tertiary or Mesozoic magmatic event. Emplacement of the Aztec Wash pluton preceded peak east west extension in the northern Eldorado Mountains (˜15.2 Ma (Gans et al., 1994)), but it coincided with at least modest extension as indicated by the uniform NS orientation of the late dikes and the mafic injections into the magma chamber. Total extension and tilting of the pluton after crystallization was minor, in contrast to the east tilted area to the north and west tilted area to the south. Timing and style of extension are thus consistent with the pluton's location within, and perhaps mechanical influence on, a major accommodation zone, as suggested by Faulds et al. (1990) and Faulds (1994).

Prognostic Significance of Serum Alkaline Phosphatase Level in Osteosarcoma: A Meta-Analysis of Published Data.

PubMed

Ren, Hai-Yong; Sun, Ling-Ling; Li, Heng-Yuan; Ye, Zhao-Ming

2015-01-01

Serum alkaline phosphatase (SALP) is commonly elevated in osteosarcoma patients. A number of studies have investigated the prognostic role of SALP level in patients with osteosarcoma but yielded inconsistent results. Systematic computerized searches were performed in PubMed, Embase, and Web of Science databases for relevant original articles. The pooled hazard ratios (HRs) and relative risks (RRs) with corresponding confidence intervals (CIs) were calculated to assess the prognostic value of SALP level. Finally, 21 studies comprising 3228 patients were included. Overall, the pooled HRs of SALP suggested that elevated level had an unfavorable impact on osteosarcoma patients' overall survival (OS) (HR = 1.82; 95% CI: 1.61-2.06; p < 0.001) and event-free survival (EFS) (HR = 1.97; 95% CI: 1.61-2.42; p < 0.001). Combined RRs of SALP indicated that elevated level was associated with presence of metastasis at diagnosis (RR = 5.55; 95% CI: 1.61-9.49; p = 0.006). No significantly different results were obtained after stratified by variables of age range, cancer stage, sample size, and geographic region. This meta-analysis demonstrated that high SALP level is significantly associated with poor OS or EFS rate and presence of metastasis at diagnosis. SALP level is a convenient and effective biomarker of prognosis for osteosarcoma.

The Critical Importance of Urinary Concentrating Ability in the Generation of Urinary Carbon Dioxide Tension

PubMed Central

Arruda, Jose A. L.; Nascimento, Luiz; Mehta, Pradeep K.; Rademacher, Donald R.; Sehy, John T.; Westenfelder, Christof; Kurtzman, Neil A.

1977-01-01

Measurement of urine to blood (U-B) carbon dioxide tension (PCO2) gradient during alkalinization of the urine has been suggested to assess distal H+ secretion. A fact that has not been considered in previous studies dealing with urinary PCO2 is that dissolution of HCO3 in water results in elevation of PCO2 which is directly proportional to the HCO3 concentration. To investigate the interrelationship of urinary HCO3 and urinary acidification, we measured U-B PCO2 in (a) the presence of enhanced H+ secretion and decreased concentrating ability i.e., chronic renal failure (CRF), (b) animals with normal H+ secretion and decreased concentrating ability, Brattleboro (BB) rats, and (c) the presence of both impaired H+ secretion and concentrating ability (LiCl treatment and after release of unilateral ureteral obstruction). At moderately elevated plasma HCO3 levels (30-40 meq/liter), normal rats achieved a highly alkaline urine (urine pH > 7.8) and raised urine HCO3 concentration and U-B PCO2. At similar plasma HCO3 levels, BB rats had a much higher fractional water excretion and failed to raise urine pH, urine HCO3 concentration, and U-B PCO2 normally. At a very high plasma HCO3 (>50 meq/liter), BB rats raised urine pH, urine HCO3 concentration, and U-B PCO2 to the same levels seen in normals. CRF rats failed to raise urine pH, urine HCO3, and U-B PCO2 normally at moderately elevated plasma HCO3 levels; at very high plasma HCO3 levels, CRF rats achieved a highly alkaline urine but failed to raise U-B PCO2. Dogs and patients with CRF were also unable to raise urine pH, urine HCO3 concentration, and U-B PCO2 normally at moderately elevated plasma HCO3 levels. In rats, dogs, and man, U-B PCO2 was directly related to urine HCO3 concentration and inversely related to fractional water excretion. At moderately elevated plasma HCO3 levels, animals with a distal acidification defect failed to raise U-B PCO2; increasing the plasma HCO3 to very high levels resulted in a significant increase in urine HCO3 concentration and U-B PCO2. The observed urinary PCO2 was very close to the PCO2 which would be expected by simple dissolution of a comparable amount of HCO3 in water. These data demonstrate that, in highly alkaline urine, urinary PCO2 is largely determined by concentration of urinary HCO3 and cannot be used as solely indicating distal H+ secretion. PMID:893680

Release of bacterial alkaline phosphatase in the rumen of cattle fed a feedlot bloat-provoking diet or a hay diet.

PubMed

Cheng, K J; Hironaka, R; Costerton, J W

1976-05-01

Alkaline phosphatase (APase) was present in the bovine rumen in both cell-free and cell-associated states and levels of the enzyme varied with dietary regime. Reaction product deposition showed that the enzyme was associated with the mixed bacterial population. No enzyme was observed to be associated with protozoa. Trace activity of APase was also detected in the saliva. The presence of large amounts of APase in cell-free rumen fluid of cattle fed fine concentrate feed is believed to be due, in part, to the breakage of bacterial cells that occurs in the rumen.

Toxic impact of aldrin on acid and alkaline phosphatase activity of penaeid prawn, Metapenaeus monoceros: In vitro study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reddy, M.S.; Jayaprada, P.; Rao, K.V.R.

1991-03-01

The increasing contamination of the aquatic environment by the indiscriminate and widespread use of different kinds of pesticides is a serious problem for environmental biologists. Organochlorine insecticides are more hazardous since they are not only more toxic but also leave residues in nature. The deleterious effects of aldrin on several crustaceans have been studied. But studies concerning the impact of aldrin on biochemical aspects of crustaceans are very much limited. The present study is aimed at probing the in vitro effects of aldrin on the acid and alkaline phosphatase activity levels in selected tissues of penaeid prawn, Metapenaeus monoceros (Fabricius).

Generic process for preparing a crystalline oxide upon a group IV semiconductor substrate

DOEpatents

McKee, Rodney A.; Walker, Frederick J.; Chisholm, Matthew F.

2000-01-01

A process for growing a crystalline oxide epitaxially upon the surface of a Group IV semiconductor, as well as a structure constructed by the process, is described. The semiconductor can be germanium or silicon, and the crystalline oxide can generally be represented by the formula (AO).sub.n (A'BO.sub.3).sub.m in which "n" and "m" are non-negative integer repeats of planes of the alkaline earth oxides or the alkaline earth-containing perovskite oxides. With atomic level control of interfacial thermodynamics in a multicomponent semiconductor/oxide system, a highly perfect interface between a semiconductor and a crystalline oxide can be obtained.

Measurement of Selected Enzymatic Activities in Solanum nigrum-Treated Biomphalaria arabica Snails

NASA Astrophysics Data System (ADS)

Al-Daihan, Sooad

In the present study, glucose, acid and alkaline phosphatases (ACP and ALP), α-amylase and lipase were measured for the first time in tissue homogenates of Biomphalaria arabica snails, molluscan intermediate host for Schistosoma mansoni in Saudi Arabia. Also, the effect of sublethal concentrations (LC25) of dry powdered Solanum nigrum leaf was tested as plant molluscicide against this snail species. The tested enzymes were altered in molluscicide-treated snails compared to control. While ALP and amylase were slightly affected, ACP and lipase were significantly altered. Glucose as an important energy source for a successful schistosome-snail relationship was significantly reduced in molluscicide-treated snails. In conclusion, sublethal concentration of the molluscicide showed potent effect in disturbing snail biochemistry which may render them physiologically unsuitable for the developing of schistosome parasite. This could be considered as a promising strategy to control the disease.

Homogeneously dispersed, multimetal oxygen-evolving catalysts

DOE PAGES

Zhang, Bo; Zheng, Xueli; Voznyy, Oleksandr; ...

2016-03-24

Earth-abundant first-row (3d) transition-metal-based catalysts have been developed for the oxygen-evolution reaction (OER); however, they operate at overpotentials significantly above thermodynamic requirements. Density functional theory suggested that non-3d high-valency metals such as tungsten can modulate 3d metal oxides, providing near-optimal adsorption energies for OER intermediates. We developed a room-temperature synthesis to produce gelled oxy-hydroxide materials with an atomically homogeneous metal distribution. These gelled FeCoW oxy-hydroxide exhibits the lowest overpotential (191 mV) reported at 10 mA per square centimeter in alkaline electrolyte. Here, the catalyst shows no evidence of degradation following more than 500 hours of operation. X-ray absorption and computationalmore » studies reveal a synergistic interplay between W, Fe and Co in producing a favorable local coordination environment and electronic structure that enhance the energetics for OER.« less

P-type proton ATPases are involved in intracellular calcium and proton uptake in the plant parasite Phytomonas francai.

PubMed

Miranda, Kildare; Vercesi, Anibal E; Catisti, Rosana; De Souza, Wanderley; Rodrigues, Claudia O; Docampo, Roberto

2005-01-01

The use of digitonin to permeabilize the plasma membrane of promastigotes of Phytomonas francai allowed the identification of two non-mitochondrial Ca(2+) compartments; one sensitive to ionomycin and vanadate (neutral or alkaline), possibly the endoplasmic reticulum, and another sensitive to the combination of nigericin plus ionomycin (acidic), possibly the acidocalcisomes. A P-type (phospho-intermediate form) Ca(2+)-ATPase activity was found to be responsible for intracellular Ca(2+) transport in these cells, with no evidence of a mitochondrial Ca(2+) transport activity. ATP-driven acidification of internal compartments in cell lysates and cells mechanically permeabilized was assayed spectrophotometrically with acridine orange. This activity was inhibited by low concentrations of vanadate and digitonin, was insensitive to bafilomycin A(1), and stimulated by Na(+) ions. Taken together, our results indicate that P-type ATPases are involved in intracellular Ca(2+) and H(+) transport in promastigotes of P. francai.

Comparison of different advanced oxidation processes for the removal of amoxicillin in aqueous solution.

PubMed

Souza, Fernanda Siqueira; da Silva, Vanessa Vargas; Rosin, Catiusa Kuchak; Hainzenreder, Luana; Arenzon, Alexandre; Féris, Liliana Amaral

2018-03-01

Amoxicillin (AMX) is a widely used penicillin-type antibiotic whose presence in the environment has been investigated. In this work, the degradation of the AMX in aqueous solutions by ozonation, ozonation with UV radiation (O 3 /UV), homogeneous catalytic ozonation (O 3 /Fe 2+ ) and homogeneous photocatalytic ozonation (O 3 /Fe 2+ /UV) was investigated. The performance results have been compared in terms of removal of amoxicillin and total organic carbon (mineralization efficiency). In all processes, complete amoxicillin degradation was obtained after 5 min. However, low mineralization was achieved. For the best available process, the potential toxicity of AMX intermediates formed after ozonation was examined using a Fish Embryo Toxicity test. Results reveal that O 3 in alkaline solution and O 3 /Fe 2+ /UV provide the highest mineralization rates. Ecotoxicity showed that no acute toxicity was observed during the exposure period of 96 h.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sievers, David A.; Lischeske, James J.; Biddy, Mary J.

Solid-liquid separation of intermediate process slurries is required in some process configurations for the conversion of lignocellulosic biomass to transportation fuels. Thermochemically pretreated and enzymatically hydrolyzed corn stover slurries have proven difficult to filter due to formation of very low permeability cakes that are rich in lignin. Treatment of two different slurries with polyelectrolyte flocculant was demonstrated to increase mean particle size and filterability. Filtration flux was greatly improved, and thus scaled filter unit capacity was increased approximately 40-fold compared with unflocculated slurry. Although additional costs were accrued using polyelectrolyte, techno-economic analysis revealed that the increase in filter capacity significantlymore » reduced overall production costs. Fuel production cost at 95% sugar recovery was reduced by $1.35 US per gallon gasoline equivalent for dilute-acid pretreated and enzymatically hydrolyzed slurries and $3.40 for slurries produced using an additional alkaline de-acetylation preprocessing step that is even more difficult to natively filter.« less

Homogeneously dispersed multimetal oxygen-evolving catalysts.

PubMed

Zhang, Bo; Zheng, Xueli; Voznyy, Oleksandr; Comin, Riccardo; Bajdich, Michal; García-Melchor, Max; Han, Lili; Xu, Jixian; Liu, Min; Zheng, Lirong; García de Arquer, F Pelayo; Dinh, Cao Thang; Fan, Fengjia; Yuan, Mingjian; Yassitepe, Emre; Chen, Ning; Regier, Tom; Liu, Pengfei; Li, Yuhang; De Luna, Phil; Janmohamed, Alyf; Xin, Huolin L; Yang, Huagui; Vojvodic, Aleksandra; Sargent, Edward H

2016-04-15

Earth-abundant first-row (3d) transition metal-based catalysts have been developed for the oxygen-evolution reaction (OER); however, they operate at overpotentials substantially above thermodynamic requirements. Density functional theory suggested that non-3d high-valency metals such as tungsten can modulate 3d metal oxides, providing near-optimal adsorption energies for OER intermediates. We developed a room-temperature synthesis to produce gelled oxyhydroxides materials with an atomically homogeneous metal distribution. These gelled FeCoW oxyhydroxides exhibit the lowest overpotential (191 millivolts) reported at 10 milliamperes per square centimeter in alkaline electrolyte. The catalyst shows no evidence of degradation after more than 500 hours of operation. X-ray absorption and computational studies reveal a synergistic interplay between tungsten, iron, and cobalt in producing a favorable local coordination environment and electronic structure that enhance the energetics for OER. Copyright © 2016, American Association for the Advancement of Science.

New 1,3,4-bisthiadiazolines: Synthesis, characterization and antimicrobial evaluations

NASA Astrophysics Data System (ADS)

Yusuf, Mohamad; Kaur, Manvinder; Jain, Payal; Solanki, Indu

2012-11-01

The bisthiadiazolines 4a-4g have been synthesized in good yields from the cyclization reactions of bisthiosemicarbazones 3a-3g with acetic anhydride. The condensation reaction of dibenzaldehydes 2a-2g with thiosemicarbazide in alcoholic medium provided 3a-3g and former were obtained from the O-alkylation of 3-hydroxybenzaldehyde with suitable 1,ω-dibromoalkanes under alkaline conditions in the presence of dry EtOH/DMF. The intermediates 3a-3g and bishetrocyclics 4a-4g were also screened for their in vitro antimicrobial activities against seven bacterial strains (Klubsellia pneumoniae, Pseudomonas aeruginosa, Escherichia coli, Straphylococcus aureus, Bacillius subtilis, Pseudomonas fluorescens and Streptoccus pyrogens) and five fungi strains (Aspergillius janus, Pencillium glabrum, Fusarium oxysporum, Aspergillus sclerotiorum, Aspergillus niger). The compounds 3f, 3g, 4f &4g were found to be significantly active against the tested microorganisms.

Methods for functionalization of microsized polystyrene beads with titania nanoparticles for cathodic electrophoretic deposition.

PubMed

Radice, S; Kern, P; Dietsch, H; Mischler, S; Michler, J

2008-02-15

Functionalization of colloidal particles based on the use of polyelectrolytes and heterocoagulation was combined with electrophoretic deposition (EPD), with the aim of depositing titania-polystyrene (TiO(2)-PS) composite particles on Ti6Al4V substrates. The composite particles were obtained by heterocoagulation of TiO(2) nanoparticles on the surface of monosized polystyrene beads of 4.6 microm in diameter. Two alternative methods were developed for the preparation of the TiO(2)-PS suspensions in organic fluids for cathodic electrodeposition. The first method was carried out in alkaline aqueous medium with the use of polyelectrolytes and intermediate control measurements of zeta potential, conductivity, and pH; the second one was carried out directly in the organic solvent used for EPD, typically isopropanol. Examples of deposits obtained by EPD in both suspensions and a comparative analysis between the two methods are presented.

Just Around the Corner... A Guide for Career Education in the Intermediate Levels.

ERIC Educational Resources Information Center

Arkansas State Dept. of Education, Little Rock. Career Education Section.

This curriculum guide provides examples of activities a teacher at the intermediate level can use for any phase of career education being studied. Activities are listed under each of the eight elements of career education: (1) Self Awareness, (2) Educational Awareness, (3) Career Awareness, (4) Economic Awareness, (5) Decision Making, (6)…

Probing the Natural World, Level III, Student Guide: Investigating Variation. Intermediate Science Curriculum Study.

ERIC Educational Resources Information Center

Bonar, John R., Ed.; Hathway, James A., Ed.

This is the student's text of one unit of the Intermediate Science Curriculum Study (ISCS) for level III students (grade 9). This unit focuses on diversity in human populations, measurement, and data collection. Numerous activities are given and optional excursions encourage students to pursue a topic in greater depth. Data tables within the…

Homogeneous Grouping and the Individualization of Instruction in Remedial Reading in an Intermediate School.

ERIC Educational Resources Information Center

Kelly, Thomas F.

A remedial reading program designed for intermediate-grade students who read from 1 to 7 years below grade level was studied. The program provided individualized instruction within classes homogeneously grouped on the basis of reading level only. Six seventh-grade classes were studied, with three acting as homogeneously grouped experimental…

Social Networking, Microlending, and Translation in the Spanish Service-Learning Classroom

ERIC Educational Resources Information Center

Faszer-McMahon, Debra

2013-01-01

This small-scale study analyzes the use of service-learning pedagogy via non-profit translation in the intermediate-level language classroom. Forty-three students at the intermediate-high level in three Spanish classes in Greensburg, Pennsylvania served as part of a translation team for the non-profit organization Kiva, which helps to fund…

21 CFR 864.7660 - Leukocyte alkaline phosphatase test.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Leukocyte alkaline phosphatase test. 864.7660... Leukocyte alkaline phosphatase test. (a) Identification. A leukocyte alkaline phosphatase test is a device used to identify the enzyme leukocyte alkaline phosphatase in neutrophilic granulocytes (granular...

21 CFR 864.7660 - Leukocyte alkaline phosphatase test.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Leukocyte alkaline phosphatase test. 864.7660... Leukocyte alkaline phosphatase test. (a) Identification. A leukocyte alkaline phosphatase test is a device used to identify the enzyme leukocyte alkaline phosphatase in neutrophilic granulocytes (granular...

21 CFR 864.7660 - Leukocyte alkaline phosphatase test.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Leukocyte alkaline phosphatase test. 864.7660... Leukocyte alkaline phosphatase test. (a) Identification. A leukocyte alkaline phosphatase test is a device used to identify the enzyme leukocyte alkaline phosphatase in neutrophilic granulocytes (granular...

Generalized thickness and configuration of the top of the intermediate aquifer, west-central Florida

USGS Publications Warehouse

Corral, Miguel A.; Wolansky, Richard M.

1984-01-01

Generalized map show the thickness and top of the intermediate aquifer in west-central Florida within the boundaries of the Southwest Florida Water Management District. The intermediate aquifer consists of a series of water-bearing units and confining beds between the surficial aquifer (water table) and the Floridan aquifer. This aquifer contains from one to several water-bearing units in west-central Florida. The aquifer and confining beds consist of the Tamiami and Hawthorn Formations of late and middle Miocene age and parts of the Tampa Limestone of early Miocene age. The top of the intermediate aquifer is about 100 feet above sea level in the north and slopes to about 100 feet below sea level in the south. The thickness ranges from zero in the north to more than 600 feet in the south. Despite the high mineral content of the water in some areas, the intermediate aquifer offers the best source of ground water to the coastal and southern areas of west-central Florida. (USGS)

Involving older people in intermediate care.

PubMed

Andrews, JoyAnn; Manthorpe, Jill; Watson, Roger

2004-05-01

Intermediate care has become a crucial part of the United Kingdom government's programme for improving services for older people. Older people comprise a substantial part of the user base for these services, and it is increasingly recognized that there is a need for greater user involvement in service development for intermediate care. National initiatives undertaken in intermediate care have sought to widen and deepen the remit of such services, and in this way promote greater independence and improved quality of care for older people. In particular, the government has set out clear plans for reshaping services for older people in the National Health Service Plan and the rationale for greater involvement of older people in service development. This article considers ways in which these national and local objectives may be achieved and considers some of the implications for nursing. This paper aims to explore the concept of intermediate care and to identify trends and existing evidence of user involvement in care. In this way it charts a possible way forward for the development of a more 'user sensitive' approach. The following databases were searched: Medline, Cochrane Library, the Social Science Citation Index and CINAHL. Key words were 'intermediate care', 'older people', 'formal care', 'primary care', 'social services' and 'geriatrics', used in combination. The findings from this study indicate that there is considerable scope for increased user involvement in service development for intermediate care. Such challenges may be more effectively met through greater clarity of the concept of intermediate care, and a bridging of user involvement at the practice and policy levels. Nurses are key providers of intermediate care in the community. The involvement of older people in intermediate care service development must be premised on a shared comprehension of the purpose and function of intermediate care. Nurses must be involved in shifting intermediate care from being service-focused to patient-centred. Effective participation eschews the application of global constructs for older people, while supporting greater participation at all levels and robust implementation processes.

Young calcareous soil chronosequences as a model for ecological restoration on alkaline mine tailings.

PubMed

Cross, Adam T; Lambers, Hans

2017-12-31

Tailings are artificial soil-forming substrates that have not been created by the natural processes of soil formation and weathering. The extreme pH environment and corresponding low availability of some macro- and micronutrients in alkaline tailings, coupled with hostile physical and geochemical conditions, present a challenging environment to native biota. Some significant nutritional constraints to ecosystem reconstruction on alkaline tailings include i) predominant or complete absence of combined nitrogen (N) and poor soil N retention; ii) the limited bioavailability of some micronutrients at high soil pH (e.g., Mn, Fe, Zn and Cu); and iii) potentially toxic levels of biologically available soil phosphorus (P) for P-sensitive plants. The short regulatory time frames (years) for mine closure on tailings landforms are at odds with the long time required for natural pedogenic processes to ameliorate these factors (thousands of years). However, there are similarities between the chemical composition and nutrient status of alkaline tailings and the poorly-developed, very young calcareous soils of biodiverse regions such as south-western Australia. We propose that basic knowledge of chronosequences that start with calcareous soils may provide an informative model for understanding the pedogenic processes required to accelerate soil formation on tailings. Development of a functional, stable root zone is crucial to successful ecological restoration on tailings, and three major processes should be facilitated as early as possible during processing or in the early stages of restoration to accelerate soil development on alkaline tailings: i) acidification of the upper tailings profile; ii) establishment of appropriate and resilient microbial communities; and iii) the early development of appropriate pioneer vegetation. Achieving successful ecological restoration outcomes on tailings landforms is likely one of the greatest challenges faced by restoration ecologists and the mining industry, and successful restoration on alkaline tailings likely depends upon careful management of substrate chemical conditions by targeted amendments. Copyright © 2017 Elsevier B.V. All rights reserved.

Anti-neovascular effect of chondrocyte-derived extracellular matrix on corneal alkaline burns in rabbits.

PubMed

Lee, Hye Sook; Lee, Ji Hyun; Kim, Chae Eun; Yang, Jae Wook

2014-06-01

We investigated the effect of a chondrocyte-derived extracellular matrix (CDECM) on experimental corneal alkaline burns in rabbits. Corneal neovascularization (NV) was induced by applying an 8-mm filter paper soaked in 1 N NaOH to the right central corneas of rabbits for 1 minute. Ten days later, the rabbits were randomly divided into three groups: the alkaline burn group, the CDECM transplantation group, and the human amniotic membrane (HAM) transplantation group. The left eyes were used as controls. CDECM and HAM were transplanted onto the corneal surface to completely cover the resected area and were subsequently sutured. On the 10th day after transplantation, the structural changes of the cornea were analyzed histologically. We examined the effects of CDECM on clinical NV features and on the expression of corneal NV markers. The alkaline burn produced significant NV and increased the corneal thickness. On day 10 after transplantation, the thickness, NV and opacity of the cornea were markedly decreased in the CDECM group (p < 0.001). However, the HAM transplantation group did not exhibit improvements in these clinical parameters, and there were no significant differences relative to the burn group. In addition, the use of CDECM improved the healing of the cornea following the alkaline burn by disrupting the corneal epithelial proliferation and reducing the fibrotic changes of the stroma. The hallmarks of NV were significantly induced in the subepithelium by the alkaline burn, and these levels were also suppressed by CDECM. The CDECM suppressed corneal NV by inhibiting nuclear factor-kappa B (NF-κB) activation by blocking the PKC and Akt signaling pathways. CDECM transplantation was markedly effective in healing alkali-burned corneas by modulating the translocation of NF-κB to the nucleus, thereby representing a promising material for the noninvasive treatment of ocular surface disease.

Multi-decadal increases in dissolved organic carbon and alkalinity flux from the Mackenzie drainage basin to the Arctic Ocean

USGS Publications Warehouse

Tank, Suzanne E.; Striegl, Robert G.; McClelland, James W.; Kokelj, Steven V.

2016-01-01

Riverine exports of organic and inorganic carbon (OC, IC) to oceans are intricately linked to processes occurring on land. Across high latitudes, thawing permafrost, alteration of hydrologic flow paths, and changes in vegetation may all affect this flux, with subsequent implications for regional and global carbon (C) budgets. Using a unique, multi-decadal dataset of continuous discharge coupled with water chemistry measurements for the Mackenzie River, we show major increases in dissolved OC (DOC) and IC (as alkalinity) fluxes since the early 1970s, for a watershed that covers 1.8 M km2 of northwestern Canada, and provides substantial inputs of freshwater and biogeochemical constituents to the Arctic Ocean. Over a 39-year period of record, DOC flux at the Mackenzie mouth increased by 39.3% (44.5 ± 22.6 Gmol), while alkalinity flux increased by 12.5% (61.5 ± 60.1 Gmol). Isotopic analyses and substantial increases in sulfate flux indicate that increases in alkalinity are driven by accelerating sulfide oxidation, a process that liberates IC from rock and soils in the absence of CO2 consumption. Seasonal and sub-catchment trends suggest that permafrost thaw plays an important role in the observed increases in DOC and alkalinity: sub-catchment increases for all constituents are confined to northern, permafrost-affected regions, while observed increases in autumn to winter are consistent with documented landscape-scale changes that have resulted from changing thaw dynamics. This increase in DOC and sulfide-derived alkalinity represents a substantial intensification of land-to-ocean C mobilization, at a level that is significant within the regional C budget. The change we observe, for example, is similar to current and projected future rates of CO2 consumption by weathering in the Mackenzie basin.

Catalytically active alkaline molten globular enzyme: Effect of pH and temperature on the structural integrity of 5-aminolevulinate synthase.

PubMed

Stojanovski, Bosko M; Breydo, Leonid; Hunter, Gregory A; Uversky, Vladimir N; Ferreira, Gloria C

2014-12-01

5-Aminolevulinate synthase (ALAS), a pyridoxal-5'phosphate (PLP)-dependent enzyme, catalyzes the first step of heme biosynthesis in mammals. Circular dichroism (CD) and fluorescence spectroscopies were used to examine the effects of pH (1.0-3.0 and 7.5-10.5) and temperature (20 and 37°C) on the structural integrity of ALAS. The secondary structure, as deduced from far-UV CD, is mostly resilient to pH and temperature changes. Partial unfolding was observed at pH2.0, but further decreasing pH resulted in acid-induced refolding of the secondary structure to nearly native levels. The tertiary structure rigidity, monitored by near-UV CD, is lost under acidic and specific alkaline conditions (pH10.5 and pH9.5/37°C), where ALAS populates a molten globule state. As the enzyme becomes less structured with increased alkalinity, the chiral environment of the internal aldimine is also modified, with a shift from a 420nm to 330nm dichroic band. Under acidic conditions, the PLP cofactor dissociates from ALAS. Reaction with 8-anilino-1-naphthalenesulfonic acid corroborates increased exposure of hydrophobic clusters in the alkaline and acidic molten globules, although the reaction is more pronounced with the latter. Furthermore, quenching the intrinsic fluorescence of ALAS with acrylamide at pH1.0 and 9.5 yielded subtly different dynamic quenching constants. The alkaline molten globule state of ALAS is catalytically active (pH9.5/37°C), although the kcat value is significantly decreased. Finally, the binding of 5-aminolevulinate restricts conformational fluctuations in the alkaline molten globule. Overall, our findings prove how the structural plasticity of ALAS contributes to reaching a functional enzyme. Copyright © 2014 Elsevier B.V. All rights reserved.

CuPt and CuPtRu Nanostructures for Ammonia Oxidation Reaction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Manso, R H.; Song, L.; Liang, Z.

Liquid fuels, such as methanol, ethanol, and ammonia, are attractive alternative to hydrogen for fuel cells due to their lower costs for storage and distribution. However, lack of sufficiently active catalysts for their oxidation reactions is a roadblock. Our previous study found that Pt 3Cu nanodendrites yielded higher activity and durability than Pt nanoparticles for methanol oxidation reaction (MOR) in acid. In this study, we synthesized two types of nanostructures of CuPt and CuPtRu catalysts via seed-mediated growth of Pt and Ru on Cu and tested their performance for ammonia oxidation reaction (AOR) in alkaline solution. Unlike for MOR, themore » nanodendrites do not promote AOR activity - CuPt performs similar to Pt and CuPtRu is less active than Pt. Interestingly, the AOR peak current is increased by 64% on CuPt nanowires and 330% on CuPtRu nanowires as compared to Pt nanoparticles. These results suggest that AOR prefers extended surface on long nanowires, distinctly differing from MOR. This can be contributed to two factors: NH 3 oxidization to N 2 involves dimerization of two N-containing intermediates to form the N-N bond and diffusion batters for adsorbed intermediates are generally lower on terrace than at low-coordination sites. This demonstrated strong effect of surface morphology will be further studied and utilized in developing advanced AOR nanocatalysts.« less

CuPt and CuPtRu Nanostructures for Ammonia Oxidation Reaction

DOE PAGES

Manso, R H.; Song, L.; Liang, Z.; ...

2018-04-01

Liquid fuels, such as methanol, ethanol, and ammonia, are attractive alternative to hydrogen for fuel cells due to their lower costs for storage and distribution. However, lack of sufficiently active catalysts for their oxidation reactions is a roadblock. Our previous study found that Pt 3Cu nanodendrites yielded higher activity and durability than Pt nanoparticles for methanol oxidation reaction (MOR) in acid. In this study, we synthesized two types of nanostructures of CuPt and CuPtRu catalysts via seed-mediated growth of Pt and Ru on Cu and tested their performance for ammonia oxidation reaction (AOR) in alkaline solution. Unlike for MOR, themore » nanodendrites do not promote AOR activity - CuPt performs similar to Pt and CuPtRu is less active than Pt. Interestingly, the AOR peak current is increased by 64% on CuPt nanowires and 330% on CuPtRu nanowires as compared to Pt nanoparticles. These results suggest that AOR prefers extended surface on long nanowires, distinctly differing from MOR. This can be contributed to two factors: NH 3 oxidization to N 2 involves dimerization of two N-containing intermediates to form the N-N bond and diffusion batters for adsorbed intermediates are generally lower on terrace than at low-coordination sites. This demonstrated strong effect of surface morphology will be further studied and utilized in developing advanced AOR nanocatalysts.« less

EPR spin trapping evidence of radical intermediates in the photo-reduction of bicarbonate/CO2 in TiO2 aqueous suspensions.

PubMed

Molinari, Alessandra; Samiolo, Luca; Amadelli, Rossano

2015-05-01

Using the EPR spin trapping technique, we prove that simultaneous reactions take place in illuminated suspensions of TiO2 in aqueous carbonate solutions (pH ≈ 7). The adsorbed HCO3(-) is reduced to formate as directly made evident by the detection of formate radicals (˙CO2(-)). In addition, the amount of OH˙ radicals from the photo-oxidation of water shows a linear dependence on the concentration of bicarbonate, indicating that electron scavenging by HCO3(-) increases the lifetime of holes. In a weakly alkaline medium, photo-oxidation of HCO3(-)/CO3(2-) to ˙CO3(-) interferes with the oxidation of water. A comparative analysis of different TiO2 samples shows that formation of ˙CO2(-) is influenced by factors related to the nature of the surface, once expected surface area effects are accounted for. Modification of the TiO2 surface with noble metal nanoparticles does not have unequivocal benefits: the overall activity improves with Pd and Rh but not with Ru, which favours HCO3(-) photo-oxidation even at pH = 7. In general, identification of radical intermediates of oxidation and reduction reactions can provide useful mechanistic information that may be used in the development of photocatalytic systems for the reduction of CO2 also stored in the form of carbonates.

Transformation of acesulfame in water under natural sunlight: joint effect of photolysis and biodegradation.

PubMed

Gan, Zhiwei; Sun, Hongwen; Wang, Ruonan; Hu, Hongwei; Zhang, Pengfei; Ren, Xinhao

2014-11-01

The transformation of acesulfame in water under environmentally relevant conditions, including direct and indirect photolysis, biodegradation, and hydrolysis, was systematically evaluated. Under natural sunlight, both direct and indirect photolysis of acesulfame were negligible in sterilized systems at neutral or alkaline pH, whereas direct photolysis occurred at pH of 4 with a rate constant of 0.0355 d(-1) in deionized water. No significant reduction in acesulfame contents was found in the dark controls or in the incubation experiments, indicating acesulfame was resistant to hydrolysis and biodegradation. In unsterilized systems, photolysis was substantially enhanced, implying that there was a joint effect of photolysis and biodegradation or that the sterilization process had the secondary effect of inactivating some photosensitizers. The near-surface summer half-life of acesulfame in the water from the Haihe River was 9 d. Specific experiments revealed the involvement of (1)O2/(3)DOM* in acesulfame photolysis, whereas OH exhibited only a slight contribution in the presence of DOM or bicarbonate. As indicated by the total organic carbon data, no significant mineralization occurred in both sterilized and unsterilized systems after acesulfame was irradiated under simulated sunlight for 7 d, suggesting the generation of persistent intermediates. Finally, major degradation intermediates were analyzed, and the degradation pathways of acesulfame under environmentally relevant conditions were proposed for the first time. Copyright © 2014 Elsevier Ltd. All rights reserved.

Synergistic effect of tungsten carbide and palladium on graphene for promoted ethanol electrooxidation.

PubMed

Yang, Jun; Xie, Ying; Wang, Ruihong; Jiang, Baojiang; Tian, Chungui; Mu, Guang; Yin, Jie; Wang, Bo; Fu, Honggang

2013-07-24

The synergistic effect of WC and Pd has large benefit for ethanol electrooxidation. The small-sized Pd nanoparticles (NPs) decorated tungsten carbide on graphene (Pd-WC/GN) will be a promising anode catalyst for the direct ethanol fuel cells. The density functional theory (DFT) calculations reveal that the strong interaction exists at the interface between Pd and WC, which induces the electron transfer from WC to Pd. Fortunately, the nanoscale architecture of Pd-WC/GN has been successfully fabricated in our experiments. X-ray photoelectron spectrum further confirms the existence of electron transfer from WC to Pd in a Pd-WC/GN nanohybrid. Notably, electrochemical tests show that the Pd-WC/GN catalyst exhibits low onset potential, a large electrochemical surface area, high activity, and stability for ethanol electrooxidation in alkaline solution compared with Pd/graphene and Pd/commercial Vulcan 72R carbon catalysts. The enhancement can be attributed to the synergistic effect of Pd and WC on graphene. At the interface between Pd and WC, the electron transfer from WC to Pd leads to the increased electron densities of surface Pd, which is available for weakening adsorption of intermediate oxygen-containing species such as CO and activating catalyst. Meanwhile, the increased tungsten oxide induced by electron transfer can facilitate the effective removal of intermediate species adsorbed on the Pd surface through a bifunctional mechanism or hydrogen spillover effect.

Root Damage under Alkaline Stress Is Associated with Reactive Oxygen Species Accumulation in Rice (Oryza sativa L.)

PubMed Central

Zhang, Hui; Liu, Xiao-Long; Zhang, Rui-Xue; Yuan, Hai-Yan; Wang, Ming-Ming; Yang, Hao-Yu; Ma, Hong-Yuan; Liu, Duo; Jiang, Chang-Jie; Liang, Zheng-Wei

2017-01-01

Alkaline stress (high pH) severely damages root cells, and consequently, inhibits rice (Oryza sativa L.) seedling growth. In this study, we demonstrate the accumulation of reactive oxygen species (ROS) in root cells under alkaline stress. Seedlings of two rice cultivars with different alkaline tolerances, ‘Dongdao-4’ (moderately alkaline-tolerant) and ‘Jiudao-51’ (alkaline-sensitive), were subjected to alkaline stress simulated by 15 mM sodium carbonate (Na2CO3). Alkaline stress greatly reduced seedling survival rate, shoot and root growth, and root vigor. Moreover, severe root cell damage was observed under alkaline stress, as shown by increased membrane injury, malondialdehyde accumulation, and Evan’s Blue staining. The expression of the cell death-related genes OsKOD1, OsHsr203j, OsCP1, and OsNAC4 was consistently upregulated, while that of a cell death-suppressor gene, OsBI1, was downregulated. Analysis of the ROS contents revealed that alkaline stress induced a marked accumulation of superoxide anions (O2•-) and hydrogen peroxide (H2O2) in rice roots. The application of procyanidins (a potent antioxidant) to rice seedlings 24 h prior to alkaline treatment significantly alleviated alkalinity-induced root damage and promoted seedling growth inhibition, which were concomitant with reduced ROS accumulation. These results suggest that root cell damage, and consequently growth inhibition, of rice seedlings under alkaline stress is closely associated with ROS accumulation. The antioxidant activity of superoxide dismutase, catalase, peroxidase, and ascorbate peroxidase increased under alkaline stress in the roots, probably in response to the cellular damage induced by oxidative stress. However, this response mechanism may be overwhelmed by the excess ROS accumulation observed under stress, resulting in oxidative damage to root cells. Our findings provide physiological insights into the molecular mechanisms of alkalinity-induced damage to root cells, and will contribute to the improvement of alkaline stress tolerance in rice plants. PMID:28943882

Root Damage under Alkaline Stress Is Associated with Reactive Oxygen Species Accumulation in Rice (Oryza sativa L.).

PubMed

Zhang, Hui; Liu, Xiao-Long; Zhang, Rui-Xue; Yuan, Hai-Yan; Wang, Ming-Ming; Yang, Hao-Yu; Ma, Hong-Yuan; Liu, Duo; Jiang, Chang-Jie; Liang, Zheng-Wei

2017-01-01

Alkaline stress (high pH) severely damages root cells, and consequently, inhibits rice ( Oryza sativa L.) seedling growth. In this study, we demonstrate the accumulation of reactive oxygen species (ROS) in root cells under alkaline stress. Seedlings of two rice cultivars with different alkaline tolerances, 'Dongdao-4' (moderately alkaline-tolerant) and 'Jiudao-51' (alkaline-sensitive), were subjected to alkaline stress simulated by 15 mM sodium carbonate (Na 2 CO 3 ). Alkaline stress greatly reduced seedling survival rate, shoot and root growth, and root vigor. Moreover, severe root cell damage was observed under alkaline stress, as shown by increased membrane injury, malondialdehyde accumulation, and Evan's Blue staining. The expression of the cell death-related genes OsKOD1 , OsHsr203j , OsCP1 , and OsNAC4 was consistently upregulated, while that of a cell death-suppressor gene, OsBI1 , was downregulated. Analysis of the ROS contents revealed that alkaline stress induced a marked accumulation of superoxide anions ([Formula: see text]) and hydrogen peroxide (H 2 O 2 ) in rice roots. The application of procyanidins (a potent antioxidant) to rice seedlings 24 h prior to alkaline treatment significantly alleviated alkalinity-induced root damage and promoted seedling growth inhibition, which were concomitant with reduced ROS accumulation. These results suggest that root cell damage, and consequently growth inhibition, of rice seedlings under alkaline stress is closely associated with ROS accumulation. The antioxidant activity of superoxide dismutase, catalase, peroxidase, and ascorbate peroxidase increased under alkaline stress in the roots, probably in response to the cellular damage induced by oxidative stress. However, this response mechanism may be overwhelmed by the excess ROS accumulation observed under stress, resulting in oxidative damage to root cells. Our findings provide physiological insights into the molecular mechanisms of alkalinity-induced damage to root cells, and will contribute to the improvement of alkaline stress tolerance in rice plants.

40 CFR 420.110 - Applicability; description of the alkaline cleaning subcategory.

Code of Federal Regulations, 2011 CFR

2011-07-01

... alkaline cleaning subcategory. 420.110 Section 420.110 Protection of Environment ENVIRONMENTAL PROTECTION... Alkaline Cleaning Subcategory § 420.110 Applicability; description of the alkaline cleaning subcategory... alkaline cleaning baths to remove mineral and animal fats or oils from the steel, and those rinsing...

40 CFR 420.110 - Applicability; description of the alkaline cleaning subcategory.

Code of Federal Regulations, 2010 CFR

2010-07-01

... alkaline cleaning subcategory. 420.110 Section 420.110 Protection of Environment ENVIRONMENTAL PROTECTION... Alkaline Cleaning Subcategory § 420.110 Applicability; description of the alkaline cleaning subcategory... alkaline cleaning baths to remove mineral and animal fats or oils from the steel, and those rinsing...

40 CFR 420.110 - Applicability; description of the alkaline cleaning subcategory.

Code of Federal Regulations, 2013 CFR

2013-07-01

... alkaline cleaning subcategory. 420.110 Section 420.110 Protection of Environment ENVIRONMENTAL PROTECTION... Alkaline Cleaning Subcategory § 420.110 Applicability; description of the alkaline cleaning subcategory... alkaline cleaning baths to remove mineral and animal fats or oils from the steel, and those rinsing...

40 CFR 420.110 - Applicability; description of the alkaline cleaning subcategory.

Code of Federal Regulations, 2012 CFR

2012-07-01

... alkaline cleaning subcategory. 420.110 Section 420.110 Protection of Environment ENVIRONMENTAL PROTECTION... Alkaline Cleaning Subcategory § 420.110 Applicability; description of the alkaline cleaning subcategory... alkaline cleaning baths to remove mineral and animal fats or oils from the steel, and those rinsing...

40 CFR 420.110 - Applicability; description of the alkaline cleaning subcategory.

Code of Federal Regulations, 2014 CFR

2014-07-01

... alkaline cleaning subcategory. 420.110 Section 420.110 Protection of Environment ENVIRONMENTAL PROTECTION... Alkaline Cleaning Subcategory § 420.110 Applicability; description of the alkaline cleaning subcategory... alkaline cleaning baths to remove mineral and animal fats or oils from the steel, and those rinsing...

Cholangiocarcinoma

MedlinePlus

... microscope Blood tests that may be done include: Liver function tests (especially alkaline phosphatase or bilirubin levels) Complete blood count (CBC) Treatment ... and may result in a cure. If the tumor is large, the entire liver may need to be removed and a liver ...

Theoretical study of the diatomic alkali and alkaline-earth oxides

NASA Technical Reports Server (NTRS)

Langhoff, S. R.; Bauschlicher, C. W., Jr.; Partridge, H.

1986-01-01

Theoretical dissociation energies for the ground states of the alkali and alkaline earth oxides are presented that are believed to be accurate to 0.1 eV. The 2 Pi - 2 Sigma + separations for the alkali oxides are found to be more sensitive to basis set than to electron correlation. Predicted 2 Pi ground states for LiO and NaO and 2 Sigma + ground states for RbO and CsO are found to be in agreement with previous theoretical and experimental work. For KO, a 2 Sigma + state is found at both the numerical Hartree-Fock (NHF) level and at the singles plus doubles configuration interaction level using a Slater basis set that is within 0.02 eV of the NHF limit. It is found that an accurate balanced treatment of the two states requires correlating the electrons on both the metal and oxide ion.

Use of ozone and hydrogen peroxide in the post-treatment of UASB treated alkaline fruit cannery effluent.

PubMed

Sigge, G O; Britz, T J; Fouri, P C; Barnardt, C A; Strydom, R

2001-01-01

UASB treatment of cannery effluents was shown to be feasible. However, the treated effluent still does not allow direct discharge to a water system and a further form of post-treatment is necessary to reduce the COD to lower than the legal limit of 75 mg/l. The use of ozone, hydrogen peroxide and granular activated carbon were used singly or in combination to assess the effectiveness as post-treatment options for the UASB treated alkaline fruit cannery effluent. Colour reduction in the effluent ranged from 15% to 92% and COD reductions of 26-91% were achieved. Combinations of ozone and hydrogen peroxide gave better results than either oxidant singly. The best results were achieved by combining ozone, hydrogen peroxide and granular activated carbon, and COD levels were reduced to levels sufficiently below the 75 mg/l limit.

Short-term variability in biomarkers of bone metabolism in sheep.

PubMed

Sousa, Cristina P; de Azevedo, Jorge T; Reis, Rui L; Gomes, Manuela E; Dias, Isabel R

2014-01-01

Changes in bone remodeling during pathological states and during their treatment can be assessed noninvasively by measuring biomarkers of bone metabolism. Their application is limited, however, by the potential biological variability in the levels of these biomarkers over time. To determine the short-term variability in biomarkers of bone metabolism in adult sheep, the authors measured serum levels of alkaline phosphatase (ALP), bone-specific alkaline phosphatase (BALP), osteocalcin (OC), N-terminal propeptide of type-III procollagen (PIIINP), deoxypyridinoline (DPD), tartrate-resistant acid phosphatase (TRAP), calcium and phosphorus intermittently over a 12-week period. There were significant differences in mean ALP activity and in phosphorus concentrations over time, but all other biomarkers showed no significant short-term variability. The results suggest that biomarkers of bone metabolism in sheep, especially the bone resorption marker DPD and the bone formation marker BALP, can be used reliably to detect changes in bone cellular activity.

Characterization of the products attained from a thermal treatment of a mix of zinc-carbon and alkaline batteries.

PubMed

Kuo, Yi-Ming; Lin, Chitsan; Wang, Jian-Wen; Huang, Kuo-Lin; Tsai, Cheng-Hsien; Wang, Chih-Ta

2016-01-01

This study applies a thermal separation process (TSP) to recover Fe, Mn, and Zn from hazardous spent zinc-carbon and alkaline batteries. In the TSP, the batteries were heated together with a reducing additive and the metals in batteries, according to their boiling points and densities, were found to move into three major output materials: slag, ingot (mainly Fe and Mn), and particulate (particularly Zn). The slag well encapsulated the heavy metals of interest and can be recycled for road pavement or building materials. The ingot had high levels of Fe (522,000 mg/kg) and Mn (253,000 mg/kg) and can serve as an additive for stainless steel-making processes. The particulate phase had a Zn level of 694,000 mg/kg which is high enough to be directly sold for refinement. Overall, the TSP effectively recovered valuable metals from the hazardous batteries.

21 CFR 862.1050 - Alkaline phosphatase or isoenzymes test system.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Alkaline phosphatase or isoenzymes test system... Test Systems § 862.1050 Alkaline phosphatase or isoenzymes test system. (a) Identification. An alkaline phosphatase or isoenzymes test system is a device intended to measure alkaline phosphatase or its isoenzymes...

Global Variability and Changes in Ocean Total Alkalinity from Aquarius Satellite

NASA Astrophysics Data System (ADS)

Fine, R. A.; Willey, D. A.; Millero, F. J., Jr.

2016-02-01

To document effects of ocean acidification it is important to have an understanding of the processes and parameters that influence alkalinity. Alkalinity is a gauge on the ability of seawater to neutralize acids. We use Aquarius satellite data, which allow unprecedented global mapping of surface total alkalinity as it correlates strongly with salinity and to a lesser extent with temperature. Spatial variability in total alkalinity and salinity exceed temporal variability, the latter includes seasonal and differences compared to climatological data. The northern hemisphere has more spatial and monthly variability in total alkalinity and salinity, while less variability in Southern Ocean alkalinity is due to less salinity variability and upwelling of waters enriched in alkalinity. Satellite alkalinity data are providing a global baseline that can be used for comparing with future carbon data, and for evaluating spatial and temporal variability and past trends. For the first time it is shown that recent satellite derived total alkalinity in the subtropics have increased as compared with climatological data; this is reflective of large scale changes in the global water cycle. Total alkalinity increases imply increased dissolution of calcareous minerals and difficulty for calcifying organisms to make their shells.

The forest, the trees, and the leaves: Differences of processing across development.

PubMed

Krakowski, Claire-Sara; Poirel, Nicolas; Vidal, Julie; Roëll, Margot; Pineau, Arlette; Borst, Grégoire; Houdé, Olivier

2016-08-01

To act and think, children and adults are continually required to ignore irrelevant visual information to focus on task-relevant items. As real-world visual information is organized into structures, we designed a feature visual search task containing 3-level hierarchical stimuli (i.e., local shapes that constituted intermediate shapes that formed the global figure) that was presented to 112 participants aged 5, 6, 9, and 21 years old. This task allowed us to explore (a) which level is perceptively the most salient at each age (i.e., the fastest detected level) and (b) what kind of attentional processing occurs for each level across development (i.e., efficient processing: detection time does not increase with the number of stimuli on the display; less efficient processing: detection time increases linearly with the growing number of distractors). Results showed that the global level was the most salient at 5 years of age, whereas the global and intermediate levels were both salient for 9-year-olds and adults. Interestingly, at 6 years of age, the intermediate level was the most salient level. Second, all participants showed an efficient processing of both intermediate and global levels of hierarchical stimuli, and a less efficient processing of the local level, suggesting a local disadvantage rather than a global advantage in visual search. The cognitive cost for selecting the local target was higher for 5- and 6-year-old children compared to 9-year-old children and adults. These results are discussed with regards to the development of executive control. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

SOLVING COPPER CORROSION PROBLEMS WHILE MAINTAINING LEAD CONTROL IN A HIGH ALKALINITY WATER USING ORTHOPHOSPHATE

EPA Science Inventory

Lead and Copper Rule sampling in 1992 uncovered high copper levels in many homes in the Indian Hill Water Works, Ohio (IHWW) water system. The 90th percentile copper and lead levels were 1.63 mg/L and 0.012 mg/L, respectively. IHWW supplies water to several suburban communities t...

Chemical composition of acid precipitation in central Texas

Treesearch

Hal B. H., Jr. Cooper; Jerry M. Demo

1976-01-01

Studies were undertaken to determine factors affecting composition of acidic precipitation formation in the Austin area of Central Texas. The study was initiated to determine background levels of acid and alkalinity producing constituents in an area with elevated natural dust levels from nearby limestone rock formations. Results showed normal rainfall pH values of 6.5...

Acid-base accounting to predict post-mining drainage quality on surface mines.

PubMed

Skousen, J; Simmons, J; McDonald, L M; Ziemkiewicz, P

2002-01-01

Acid-base accounting (ABA) is an analytical procedure that provides values to help assess the acid-producing and acid-neutralizing potential of overburden rocks prior to coal mining and other large-scale excavations. This procedure was developed by West Virginia University scientists during the 1960s. After the passage of laws requiring an assessment of surface mining on water quality, ABA became a preferred method to predict post-mining water quality, and permitting decisions for surface mines are largely based on the values determined by ABA. To predict the post-mining water quality, the amount of acid-producing rock is compared with the amount of acid-neutralizing rock, and a prediction of the water quality at the site (whether acid or alkaline) is obtained. We gathered geologic and geographic data for 56 mined sites in West Virginia, which allowed us to estimate total overburden amounts, and values were determined for maximum potential acidity (MPA), neutralization potential (NP), net neutralization potential (NNP), and NP to MPA ratios for each site based on ABA. These values were correlated to post-mining water quality from springs or seeps on the mined property. Overburden mass was determined by three methods, with the method used by Pennsylvania researchers showing the most accurate results for overburden mass. A poor relationship existed between MPA and post-mining water quality, NP was intermediate, and NNP and the NP to MPA ratio showed the best prediction accuracy. In this study, NNP and the NP to MPA ratio gave identical water quality prediction results. Therefore, with NP to MPA ratios, values were separated into categories: <1 should produce acid drainage, between 1 and 2 can produce either acid or alkaline water conditions, and >2 should produce alkaline water. On our 56 surface mined sites, NP to MPA ratios varied from 0.1 to 31, and six sites (11%) did not fit the expected pattern using this category approach. Two sites with ratios <1 did not produce acid drainage as predicted (the drainage was neutral), and four sites with a ratio >2 produced acid drainage when they should not have. These latter four sites were either mined very slowly, had nonrepresentative ABA data, received water from an adjacent underground mine, or had a surface mining practice that degraded the water. In general, an NP to MPA ratio of <1 produced mostly acid drainage sites, between 1 and 2 produced mostly alkaline drainage sites, while NP to MPA ratios >2 produced alkaline drainage with a few exceptions. Using these values, ABA is a good tool to assess overburden quality before surface mining and to predict post-mining drainage quality after mining. The interpretation from ABA values was correct in 50 out of 52 cases (96%), excluding the four anomalous sites, which had acid water for reasons other than overburden quality.

Variable sources for Cretaceous to recent HIMU and HIMU-like intraplate magmatism in New Zealand

NASA Astrophysics Data System (ADS)

van der Meer, Q. H. A.; Waight, T. E.; Scott, J. M.; Münker, C.

2017-07-01

Continental intraplate magmas with isotopic affinities similar to HIMU are identified worldwide. Involvement of an asthenospheric HIMU or HIMU-like source is contested because the characteristic radiogenic Pb compositions coupled with unradiogenic Sr and intermediate Nd and Hf compositions can also result from in-situ ingrowth in metasomatised lithospheric mantle. Sr-Nd-Pb-Hf isotopic compositions of late Cretaceous lamprophyre dikes from Westland, New Zealand, provide new insights into the formation of a HIMU-like alkaline intraplate magmatic province under the Zealandia continent. The oldest (102-100 Ma) calc-alkaline lamprophyres are compositionally similar to the preceding arc-magmatism (206Pb/204Pb(i) = 18.6, 207Pb/204Pb(i) = 15.62, 208Pb/204Pb(i) = 38.6, 87Sr/86Sr(i) = 0.7063-0.7074, εNd(i) = -2.1 - +0.1 and εHf(i) = -0.2 - +2.3) and are interpreted as melts originating from subduction-modified lithosphere. Alkaline dikes erupted on the inboard Gondwana margin shortly after cessation of subduction (92-84 Ma) have heterogeneous isotopic properties: 206Pb/204Pb(i) = 18.7 to 19.4, 207Pb/204Pb(i) = 15.60 to 15.65, 208Pb/204Pb(i) = 38.6 to 39.4, 87Sr/86Sr(i) = 0.7031 to 0.7068, εNd(i) = +4.5 to +8.0 and εHf(i) = +5.1 to +8.0. Melt compositions point to an amphibole-bearing spinel facies lithospheric mantle source enriched by metasomatism that introduced, amongst many elements, U + Th which lead to rapid ingrowth to HIMU-like compositions. Importantly, this HIMU-like source enrichment appears to have completely originated from the complex local subduction history. A coeval episode of alkaline magmatism (mainly 98-82 Ma) occurred outboard of Gondwana's former active margin and on the Hikurangi oceanic plateau (accreted to Zealandia in the Early Cretaceous) with compositions closer to true HIMU (206Pb/204Pb(i) ≈ 20.5, 207Pb/204Pb(i) ≈ 15.7, 208Pb/204Pb(i) ≈ 40.0, εNd(i) ≈ 4.5 and εHf(i) ≈ 4.0). In contrast to the inboard HIMU-like magmas, the radiogenic 207Pb/204Pb and relatively unradiogenic Nd and Hf require an ancient enriched source component. This magmatism is interpreted to represent melting of a fossilised HIMU source that resided under the Hikurangi Plateau. These genetically distinct but isotopically similar intraplate reservoirs were separated by the down-going slab under Gondwana's former active margin. Ancient HIMU magmatism was locally replaced by the young HIMU-like type which became dominant across Zealandia during the Late Cretaceous. Our research suggests that the sources for alkaline intraplate magmas with compositions similar to ocean island basalts can be formed either with or without the involvement of a plume-derived component.

Biological Apatite Formed from Polyphosphate and Alkaline Phosphatase May Exchange Oxygen Isotopes from Water through Carbonate

NASA Astrophysics Data System (ADS)

Omelon, S. J.; Stanley, S. Y.; Gorelikov, I.; Matsuura, N.

2011-12-01

The oxygen isotopic composition in bone mineral phosphate is known to reflect the local water composition, environmental humidity, and diet1. Once ingested, biochemical processes presumably equilibrate PO43- with "body water" by the many biochemical reactions involving PO43- 2. Blake et al. demonstrated that enzymatic release of PO43- from organophosphorus compounds, and microbial metabolism of dissolved orthophosphate, significantly exchange the oxygen in precipitated apatite within environmental water3,4, which otherwise does not exchange with water at low temperatures. One of the enzymes that can cleave phosphates from organic substrates is alkaline phosphastase5, the enzyme also associated with bone mineralization. The literature often states that the mineral in bone in hydroxylapatite, however the mineral in bone is carbonated apatite that also contains some fluoride6. Deprotonation of HPO32- occurs at pH 12, which is impossibly high for biological system, and the predominate carbonate species in solution at neutral pH is HCO3-. To produce an apatite mineral without a significant hydroxyl content, it is possible that apatite biomineralization occurs through a polyphosphate pathway, where the oxygen atom required to transform polyphosphate into individual phosphate ions is from carbonate: [PO3-]n + CO32- -> [PO3-]n-1 + PO43- + CO2. Alkaline phosphatase can depolymerise polyphosphate into orthophosphate5. If alkaline phosphatase cleaves an oxygen atom from a calcium-carbonate complex, then there is no requirement for removing a hydrogen atom from the HCO3- or HPO43- ions of body water to form bioapatite. A mix of 1 mL of 1 M calcium polyphosphate hydogel, or nano-particles of calcium polyphosphate, and amorphous calcium carbonate were reacted with alkaline phosphatase, and maintained at neutral to basic pH. After two weeks, carbonated apatite and other calcium phosphate minerals were identified by powder x-ray diffraction. Orthophosphate and unreacted polyphosphate species were detected by Raman and IR spectroscopy. The oxygen isotope data of the reactants and products will also be presented. The possibility that carbonate acts as an intermediate reagent, transferring the oxygen from water to phosphate in biological apatite mineral formation may explain why biological apatite exhibits a significant carbonate content, and how this mineral is formed with an insignificant hydroxyl content. 1 Kohn, M.J., and Cerling, T.E. Rev Mineral Geochem 2002 (48) 455 2 Kolodny, Y., Luz, B., Navon, O. Earth Planet Sci Lett 1983 (64) 398 3 Blake, R.E., O'Neil, J.R., Garcia, G.A. Geochim et Cosmochim Acta 1997 (61) 4411 4 Blake, R.E., Alt, J.C., and Martini, A.M. PNAS 2001 (98) 2148-2153 5 Liang, Y., and Blake, R.E. Geochim Cosmochim Acta 2009 (73) 3782) 6 Pasteris, J.D. et al. Biomaterials 2004 (35) 229 7 Omelon et al., PLoS ONE 2009 4(5), e5634

Cellular and humoral immunity after vaccination or natural mumps infection.

PubMed

Terada, Kihei; Hagihara, Kimiko; Oishi, Tomohiro; Miyata, Ippei; Akaike, Hiroto; Ogita, Satoko; Ohno, Naoki; Ouchi, Kazunobu

2017-08-01

This study measured cell-mediated immunity (CMI) and serum antibody to clarify the basis of breakthrough after vaccination and reinfection after mumps. From a pool of 54 college students, 17 seronegative subjects and 14 subjects with intermediate level of antibodies against mumps were vaccinated with a monovalent mumps vaccine, and CMI was assessed using interferon-γ release assay. CMI positivity according to pre-existing antibody level, defined as titer <2.0 index units, negative; 2.0-3.9 index units, intermediate; and ≥4.0 index units, positive, was 8/17 (47.1%), 9/14 (64.3%) and 19/23 (82.6%) before vaccination, respectively. Of the 17 seronegative subjects, seven (41.2%) had a history of vaccination and/or natural infection, four (57.1%) of whom were CMI positive or intermediate. Ten (71%) of 14 subjects with intermediate antibody level had a history of vaccination or natural infection, eight (80%) of whom were CMI positive or intermediate. After vaccination the interferon (IFN)-γ and antibody titers increased significantly, but seven (41.2%) of the 17 seronegative subjects and 13 (92.9%) of the 14 intermediate-level subjects tested positive for both antibody and CMI. In a comparison of the natural infection group (confirmed as IgG seropositive and/or CMI positive without vaccination) versus the vaccination group, IgG antibody titer (mean ± SD) was 14.4 ± 8.0 versus 3.6 ± 2.4 index units (P < 0.01) and IFN-γ was 122.7 ± 90.0 pg/mL versus 59.5 ± 37.8 pg/mL (P > 0.05), respectively. Vaccination or even natural mumps infection did not always induce both cellular and humoral immunity. © 2017 Japan Pediatric Society.

Multi-shell spherical GaAs /AlxGa1-x As quantum dot shells-size distribution as a mechanism to generate intermediate band energy levels

NASA Astrophysics Data System (ADS)

Rodríguez-Magdaleno, K. A.; Pérez-Álvarez, R.; Martínez-Orozco, J. C.; Pernas-Salomón, R.

2017-04-01

In this work the generation of an intermediate band of energy levels from multi-shell spherical GaAs /AlxGa1-x As quantum dot shells-size distribution is reported. Within the effective mass approximation the electronic structure of a GaAs spherical quantum-dot surrounded by one, two and three shells is studied in detail using a numerically stable transfer matrix method. We found that a shells-size distribution characterized by continuously wider GaAs domains is a suitable mechanism to generate the intermediate band whose width is also dependent on the Aluminium concentration x. Our results suggest that this effective mechanism can be used for the design of wider intermediate band than reported in other quantum systems with possible solar cells enhanced performance.

The ARES High-level Intermediate Representation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moss, Nicholas David

The LLVM intermediate representation (IR) lacks semantic constructs for depicting common high-performance operations such as parallel and concurrent execution, communication and synchronization. Currently, representing such semantics in LLVM requires either extending the intermediate form (a signi cant undertaking) or the use of ad hoc indirect means such as encoding them as intrinsics and/or the use of metadata constructs. In this paper we discuss a work in progress to explore the design and implementation of a new compilation stage and associated high-level intermediate form that is placed between the abstract syntax tree and when it is lowered to LLVM's IR. Thismore » highlevel representation is a superset of LLVM IR and supports the direct representation of these common parallel computing constructs along with the infrastructure for supporting analysis and transformation passes on this representation.« less

Use of low density lipoprotein particle number levels as an aid in statin treatment decisions for intermediate risk patients: a cost-effectiveness analysis.

PubMed

Shiffman, Dov; Arellano, Andre R; Caulfield, Michael P; Louie, Judy Z; Bare, Lance A; Devlin, James J; Melander, Olle

2016-12-07

The 2013 ACC/AHA guideline recommended either no statin therapy or moderate-intensity statin therapy (MST) for intermediate risk patients-those with 5-7.5% 10-year risk and without cardiovascular disease (CVD), hypercholesterolemia or diabetes. The guideline further suggested that the therapy choice be based on patient-clinician discussions of risks and benefits. Since low-density lipoprotein particle (LDL-P) levels were reported to be associated with CVD independently of traditional risk factors in intermediate and low risk patients, we investigated the cost-effectiveness of using LDL-P levels to identify intermediate risk patients likely to benefit from initiating or intensifying statin therapy. We evaluated 5 care strategies for intermediate risk patients. These included the strategies suggested by the guideline: no-statin therapy and MST. We compared each of these strategies to a related strategy that incorporated LDL-P testing. No-statin therapy was compared with the strategy of MST for those with high LDL-P levels and no statin therapy for all other patients (test-and-MST). MST was compared with the strategy of high-intensity statin therapy (HST) for those with high LDL-P levels and MST for all other patients (test-and-HST). We also evaluated the strategy of HST for all. Costs (payer perspective) and utilities were assessed over a 5-year time horizon in a Markov model of 100,000 hypothetical intermediate risk patients. HST dominated all other strategies, costing less and-despite causing 739 more cases of diabetes than did MST-resulting in more quality adjusted life-years (QALYs). For patient-clinician discussions that would otherwise lead to the MST strategy, we found the test-and-HST strategy reduced costs by $4.67 MM and resulted in 134 fewer CVD events and 115 additional QALYs. For patient-clinician discussions that would otherwise lead to no statin therapy, we found that the test-and-MST strategy reduced costs by $3.25 MM, resulted in 97 fewer CVD events and 44 additional QALYs. The HST strategy was cost saving and improved outcomes in intermediate risk patients. For patient and clinicians concerned about the adverse events associated with HST, using LDL-P levels to target intensified statin therapy could improve outcomes and reduce costs.

An Examination of the Quality of Literacy Skill Assessments across Levels of Second-Grade, Spanish-Speaking, English-Language Learners

ERIC Educational Resources Information Center

Gutierrez, Gabriel

2010-01-01

The current study examined the quality of the Dynamic Indicators of Basic Early Literacy Skills (DIBELS) across a sample of second-grade English Language (EL) learners with varying degrees of English proficiency (e.g., students with beginning, early intermediate, intermediate, early advanced, and advanced levels). DIBELS Oral Reading Fluency…