Adsorption and desorption of phosphate on limestone in experiments simulating seawater intrusion

This study investigates the potential release of from carbonate aquifers exposed to seawater intrusion. Adsorption and desorption of in the presence of deionized water (DIW) and seawater were conducted on a large block of Pleistocene age limestone to simulate the effects of seawater intrusion into a coastal carbonate aquifer at the laboratory scale. The limestone showed strong adsorption of in DIW, while adsorption was significantly less in the presence of seawater. Dissolution of CaCO3 was found to prevent adsorption at salinities less than 30 psu. Adsorption of was limited at higher salinities (30–33 psu), due to competition with ions for adsorption sites. At a salinity3 precipitated. Concentrations of between 2 and 5 μmol/L were released by desorption when the limestone was exposed to seawater. The results of this study suggest that as seawater intrudes into an originally freshwater coastal aquifer, adsorbed may be released into the groundwater. Consequently, adsorbed is expected to be released from coastal carbonate aquifers world-wide as sea level continues to rise exposing more of the freshwater aquifer to seawater

Does prior coronary angioplasty affect outcomes of surgical coronary revascularization? Insights from the STICH trial

Background: The STICH trial showed superiority of coronary artery bypass plus medical treatment (CABG) over medical treatment alone (MED) in patients with left ventricular ejection fraction (LVEF) ≤35%. In previous publications, percutaneous coronary intervention (PCI) prior to CABG was associated with worse prognosis. Objectives: The main purpose of this study was to analyse if prior PCI influenced outcomes in STICH. Methods and results: Patients in the STICH trial (n = 1212), followed for a median time of 9.8 years, were included in the present analyses. In the total population, 156 had a prior PCI (74 and 82, respectively, in the MED and CABG groups). In those with vs. without prior PCI, the adjusted hazard-ratios (aHRs) were 0.92 (95% CI = 0.74–1.15) for all-cause mortality, 0.85 (95% CI = 0.64–1.11) for CV mortality, and 1.43 (95% CI = 1.15–1.77) for CV hospitalization. In the group randomized to CABG without prior PCI, the aHRs were 0.82 (95% CI = 0.70–0.95) for all-cause mortality, 0.75 (95% CI = 0.62–0.90) for CV mortality and 0.67 (95% CI = 0.56–0.80) for CV hospitalization. In the group randomized to CABG with prior PCI, the aHRs were 0.76 (95% CI = 0.50–1.15) for all-cause mortality, 0.81 (95% CI = 0.49–1.36) for CV mortality and 0.61 (95% CI = 0.41–0.90) for CV hospitalization. There was no evidence of interaction between randomized treatment and prior PCI for any endpoint (all adjusted p > 0.05). Conclusion: In the STICH trial, prior PCI did not affect the outcomes of patients whether they were treated medically or surgically, and the superiority of CABG over MED remained unchanged regardless of prior PCI. Clinical trial registration: Clinicaltrials.gov; Identifier: NCT0002359

Identification of a cDNA encoding a long form of prolactin receptor in human hepatoma and breast cancer cells

International audienc

La participation à des activités parascolaires à l’adolescence : l’importance de la motivation autonome

Plusieurs études ont démontré que la participation à des activités parascolaires (sports, arts, civiques) contribue au fonctionnement psychologique des adolescents. Cependant, les motivations derrière leur participation ont souvent été négligées. La présente étude a examiné l’association entre la participation à des activités parascolaires, d’une part, et les types de motivation à participer, d’autre part, reliée au fonctionnement psychologique. Étant donné la nature particulière des activités civiques, cette étude a également vérifié si les motivations à s’engager dans des activités civiques étaient associées plus fortement au fonctionnement psychologique que les motivations pour les activités non civiques. Au total, 1622 élèves (64 % de filles) du secondaire ont fait part de leur participation à des activités civiques et non civiques ainsi que leurs motivations (autonome ou contrôlée) à participer. Ils ont également répondu à des mesures de fonctionnement psychologique : estime de soi, satisfaction des besoins psychologiques, qualité des relations interpersonnelles (parents et ami) et attachement envers l’école. Les résultats ont révélé que le fait de participer ou non à des activités parascolaires était faiblement associé au fonctionnement psychologique des adolescents. Cependant, la motivation autonome pour les activités était associée positivement au fonctionnement psychologique, tandis que pour la motivation contrôlée, l’association était négative, et ce, au-delà des variables contrôlées. De plus, chez les adolescents participant aux deux types d’activités, la motivation autonome pour les activités civiques était le meilleur prédicteur du fonctionnement psychologique. Ces résultats suggèrent que les types de motivations à participer doivent être pris en compte au-delà de la simple participation.Several studies have shown that adolescents’ participation in extracurricular activities (such as sports, arts, and civic) can contribute to their psychological functioning. However, the motivational aspect of their participation has been neglected. The present study examined the association between participation in extracurricular activities and adolescents’ psychological functioning. More specifically, it was investigated whether certain types of motivation to engage in the activity were differentially associated with adolescents’ psychological functioning. Considering the special nature of civic engagement, this study also investigated whether autonomous motivation for civic activities was more strongly linked to psychological functioning than autonomous motivation for non-civic activities. In total, 1622 high school students reported their participation in civic and non-civic activities and their motivation (autonomous or controlled) to participate. They also completed psychological functioning measures including self-esteem, basic needs satisfaction, quality of interpersonal relationships with parents and friend, and attachment to their school. The results revealed that participation was weakly associated with adolescents’ psychological functioning. However, autonomous motivation for activities was positively associated with psychological functioning, whereas for controlled motivation, the link was negative. Moreover, for adolescents that participated in both types of activities, the best predictor of psychological functioning was autonomous motivation for civic activities. These results suggest that the type of motivation in participation should be taken into consideration

Milium lendigerum

The metabolism of potato (Solanum tuberosum) roots constitutively over-and underexpressing hexokinase (HK, EC 2.7.1.1) was examined. An 11-fold variation in HK activity resulted in altered root growth, with antisense roots growing better than sense roots. Quantification of sugars, organic acids and amino acids in transgenic roots demonstrated that the manipulation of HK activity had very little effect on the intracellular pools of these metabolites. However, adenylate and free Pi levels were negatively affected by an increase in HK activity. The flux control coefficient of HK over the phosphorylation of glucose was measured for the first time in plants. Its value varied with HK level. It reached 1.71 at or below normal HK activity value and was much lower (0.32) at very high HK levels. Measurements of glycolytic flux and O-2 uptake rates demonstrated that the differences in glucose phosphorylation did not affect significantly glycolytic and respiratory metabolism. We hypothesized that these results could be explained by the existence of a futile cycle between the pools of hexose-Ps and carbohydrates. This view is supported by several lines of evidence. Firstly, activities of enzymes capable of catalyzing these reactions were detected in roots, including a hexose-P phosphatase. Secondly, metabolic tracer experiments using C-14-glucose as precursor showed the formation of C-14-fructose and C-14-sucrose. We conclude that futile cycling of hexose-P could be partially responsible for the differences in energetic status in roots with high and low HK activity and possibly cause the observed alterations in growth in transgenic roots. The involvement of HK and futile cycles in the control of glucose-6P metabolism is discussed

Effects of altered HK activity levels on potato root growth.

<p>a Representative pictures of antisense (AS301), control (Ctrl3) and sense (S107) clones grown for 14 d from a single 0.7 cm-long root tip. Total root length (b), tip number (c) and mean diameter (d) were assessed for antisense (black circles), control (grey circles) and sense (grey triangles) clones after 14 d of growth on solid MS medium. Y values are means ± SE of quadruplicates from two independent experiments, X values are from Fig. 1.</p

Total extractible HK activity and protein levels in transgenic potato root clones.

<p>Specific activities were measured with Glc (GK activity, a) and Fru (FK activity, b) in antisense (AS), control (Ctrl) and sense (S) clones. Values are means ± SE from three to ten separate extractions. Immunoblot analysis (c) of HK protein levels in potato root clones. Immunodetection was carried out with affinity-purified IgGs raised against recombinant ScHK2. Each lane was loaded with 6.5 µg of protein. The names of the clones at the bottom of the bar graph also identify the lanes in panel (c).</p

Pi pools and intracellular pHs.

<p>Pi quantification was done using a colorimetric assay. Intracellular Pi pools and pHs were measured by <i>in vivo</i>³¹P NMR. Root cultures (0.5–0.8 g FW) were inserted into a 10 mm NMR tube perfused with oxygenated MS medium. Spectra were recorded over periods of 1 h on a Varian Unity Inova 400 MHz NMR spectrometer.</p