The effect of pH and hardness metal ions on the competitive interaction between trace metal ions and inorganic and organic complexing agents found in natural waters

The effect of pH and hardness metal ions on the interactions between trace metals and both inorganic and organic complexing agents has been studied under conditions simulating natural aquatic conditions, by employing anodic stripping voltammetric titration techniques. The complexation of Bi(III), Cd(II), Cu(II), Pb(II), and Tl(I) with the hydroxo- and carbonato-ligands found in a carbonate medium has been observed to generally increase with increasing pH. Both labile and nonlabile interactions have been observed. Nonlabile interactions are predominant at low pH and labile interactions generally increase with increasing pH. Neither calcium nor magnesium affects these interactions. The complexation of humic acids with trace metals in a carbonate medium was found to be more intense than metal ion-inorganic complexation. Both labile and nonlabile complexation was found; however, no generalizations can be made concerning the type and extent of complexation because of the individual nature of the interactions of each trace metal. Calcium was found to be more effective than magnesium in inhibiting trace metal-organic complexation. The effect of calcium is to inhibit labile complexation and is most pronounced with the cadmium-humic acid system.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/22766/1/0000321.pd

Everything is not everywhere: can marine compartments shape phytoplankton assemblages?

The idea that ‘everything is everywhere, but the environment selects' has been seminal in microbial biogeography, and marine phytoplankton is one of the prototypical groups used to illustrate this. The typical argument has been that phytoplankton is ubiquitous, but that distinct assemblages form under environmental selection. It is well established that phytoplankton assemblages vary considerably between coastal ecosystems. However, the relative roles of compartmentalization of regional seas and site-specific environmental conditions in shaping assemblage structures have not been specifically examined. We collected data from coastal embayments that fall within two different water compartments within the same regional sea and are characterized by highly localized environmental pressures. We used principal coordinates of neighbour matrices (PCNM) and asymmetric eigenvector maps (AEM) models to partition the effects that spatial structures, environmental conditions and their overlap had on the variation in assemblage composition. Our models explained a high percentage of variation in assemblage composition (59–65%) and showed that spatial structure consistent with marine compartmentalization played a more important role than local environmental conditions. At least during the study period, surface currents connecting sites within the two compartments failed to generate sufficient dispersal to offset the impact of differences due to compartmentalization. In other words, our findings suggest that, even for a prototypical cosmopolitan group, everything is not everywhere

Impact of diabetes continuing education on health care professionals’ attitudes towards diabetes care in a Yemeni city

Purpose: To evaluate the impact of a continuing education (CE) program on the attitudes of health care professionals (HCPs) towards diabetes care in Yemen.Methods: A pre- and post-intervention study was carried out in Mukalla City, Hadramout, Yemen and was offered to all physicians, pharmacists, and nurses registered in the Health Office in the Mukalla City. The HCPs were invited to attend a CE program. All participants filled out a questionnaire before the intervention (pre-test) that measured the attitudes of the participants towards diabetes. An interventional program was given in the form of a seminar, and participants were requested to complete the same questionnaire after the seminar.Results: A total of 73 HCPs attended the CE, including 19 pharmacists (26 %), 37 physicians (50.7 %), and 17 (23.3 %) nurses. The pre- and post-intervention changes in the questionnaire responses were significant only for attitude toward the values of blood glucose levels (p = 0.009) and attitude toward autonomy of diabetes patients (p = 0.023).Conclusion: HCPs in Mukalla City have positive attitudes toward diabetes. Physicians were more aware of the sequelae of diabetes than other healthcare professional groups with nurses showing the least understanding. Therefore, more emphasis should be placed upon designing education programs for diabetes specifically tailored for nurses and pharmacists.Keywords: Diabetes, Continuing education, Attitude, Health care professional

The metabolomic analysis of five Mentha species: cytotoxicity, anti-Helicobacter assessment, and the development of polymeric micelles for enhancing the anti-Helicobacter activity

Mentha species are medicinally used worldwide and remain attractive for research due to the diversity of their phytoconstituents and large therapeutic indices for various ailments. This study used the metabolomics examination of five Mentha species (M. suaveolens, M. sylvestris, M. piperita, M. longifolia, and M. viridis) to justify their cytotoxicity and their anti-Helicobacter effects. The activities of species were correlated with their phytochemical profiles by orthogonal partial least square discriminant analysis (OPLS-DA). Tentatively characterized phytoconstituents using liquid chromatography high-resolution electrospray ionization mass spectrometry (LC-HR-ESI-MS) included 49 compounds: 14 flavonoids, 10 caffeic acid esters, 7 phenolic acids, and other constituents. M. piperita showed the highest cytotoxicity to HepG2 (human hepatoma), MCF-7 (human breast adenocarcinoma), and CACO2 (human colon adenocarcinoma) cells using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays. OPLS-DA and dereplication studies predicted that the cytotoxic activity was related to benzyl glucopyranoside-sulfate, a lignin glycoside. Furthermore, M. viridis was effective in suppressing the growth of Helicobacter pylori at a concentration of 50 mg mL−1. OPLS-DA predicted that this activity was related to a dihydroxytrimethoxyflavone. M. viridis extract was formulated with Pluronic® F127 to develop polymeric micelles as a nanocarrier that enhanced the anti-Helicobacter activity of the extract and provided minimum inhibitory concentrations and minimum bactericidal concentrations of 6.5 and 50 mg mL−1, respectively. This activity was also correlated to tentatively identified constituents, including rosmarinic acid, catechins, carvone, and piperitone oxide

Rapid toxicity testing based on mitochondrial respiratory activity

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47992/1/128_2005_Article_BF01701787.pd

Which efficacy constructs for large-scale social dilemma problems? Individual and collective forms of efficacy and outcome expectancies in the context of climate change mitigation

Effective management of climate change risk requires an understanding of how to encourage positive behaviour change at the collective level. The urgency of the problem and the social dilemma nature of decisions about whether to engage in pro-environmental behaviours raise particular challenges for policy makers and those involved in designing interventions. Evidence reveals that efficacy beliefs (judgements of the ease of carrying out a particular act) and outcome expectancy beliefs (judgements of the value of acts in reaching goals) function as important determinants of human motivation and action (Bandura, 1995). However, efficacy and associated constructs remain poorly theorised at the collective level, particularly in social dilemma situations where goals may exist at both individual and collective levels. We develop a framework that incorporates collective forms of efficacy and outcome expectancy for large-scale, social dilemma situations, and operationalise these constructs. We then discuss how this framework can support us in managing climate change risk by allowing us to identify the specific forms of efficacy and outcome expectancy that should be targeted in research, science communication and policy

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A Computational Determination of Reactivity Descriptors, Vibrational Analysis and Nuclear Magnetic Resonance of (E)-5-oxo-1-phenyl-4-(2-phenylhydrazono)-4,5-dihydro- 1H-pyrazole-3-carbaldehyde

The title compound, pyrazole carbaldehyde have been optimized using Gaussian 9 software program, via density functional theory framework (DFT/B3LYP) by 6-311G (d, p) basis set, the output file was visualize using Gaussian view program, geometric properties, thermochemical and reactivity descriptors such as ionization potential (IP), electron affinity (EA), electronegativity (χ), chemical potential (μ), hardness (η), softness (σ), electrophilicity index (ω) and nucleophilicity index (N) were calculated.  Mapping of electrostatic surface potential (MESP) allow us to establish trends that enable making predictions about the reactive sites of the studied compound. Besides, the optimized structure is subjected to frequency analysis at the same level of theory to obtain thermodynamic correction values. Vibrational assignments and nuclear magnetic resonance (1H- &13C-NMR) chemical shifts of the molecule were calculated by gauge independent atomic orbital (GIAO) method using the CPCM model, and mapping of current density shielding of proton and carbon nucleus of the aldehyde group shied light on the molecular properties and reactivity of 5-oxo-1-phenyl-4-(2-phenylhydrazono)-4,5- dihydro-1H-pyrazole-3-carbaldehyde

Improvement of poor subgrade soils using cement kiln dust

Construction of pavements layers on subgrade with excellent to good properties reduces the thickness of the layers and consequently reduces the initial and maintenance cost of highways and vice versa. However, construction of pavements on poor subgrade is unavoidable due to several constrains. Improvement of subgrade properties using traditional additives such as lime and Portland cement adds supplementary costs. Therefore, using by-products in this domain involves technical, economic, and environmental advantages. Cement kiln dust (CKD) is generated in huge quantities as a by-product material in Portland cement plants. Therefore, it can be considered as an excellent alternative in this domain. In Iraq, Portland cement plants generate about 350000 tons of CKD annually which is available for free. Therefore, Iraq can be adopted as a case study. This paper covers using CKD to improve the properties of poor subgrade soils based on series of California Bearing Ration (CBR) tests on sets of untreated samples and samples treated with different doses of CKD in combination with different curing periods to investigate their effects on soil properties. The results exhibited that adding 20% of CKD with curing for 14 days increases the CBR value from 3.4% for untreated soil to 48% for treated soil; it, also, decreases the swelling ratio. To determine the effects of using this dose under the mentioned curing period on the designed thicknesses of pavements layers, a case study was adopted. The case study results exhibited that treatment of the subgrade soil by 20% of CKD with curing for 14 days reduces the cost of the pavements by $25.875 per square meter