Integration of iron in natural and synthetic Al-pyrophyllites: an infrared spectroscopic study

Numerous studies focus on the relationships between chemical composition and OHband positions in the infrared (IR) spectra of micaceous minerals. These studies are based on the coexistence, in dioctahedral micas or smectites, of several cationic pairs around the hydroxyl group which each produce a characteristic band in the IR spectrum. The aim of this work is to obtain the wavenumber values of the IR OH vibration bands of the (Al-Fe3+)-OH and (Fe3+-Fe3+)-OH local cationic environments of 'pyrophyllite type' in order to prove, disprove or modify a model of dioctahedral phyllosilicate OH-stretching band decomposition. Natural samples are characterized by powder X-ray diffraction (XRD), Fourier transform infrared (FTIR) and Raman spectroscopies and electron microprobe; the hydrothermal synthesis products are also analysed by powder XRD and FTIR after inductively coupled plasma measurements to obtain the chemical compositions of nascent gel phases. Natural samples contain some impurities which were eliminated after acid treatment; nevertheless, a small Fe content is found in the pyrophyllite structure. The amount of Fe which is incorporated within the pyrophyllite structure is much more important for the synthetic samples than for the natural ones. The IR OH bands were clearly observed in both natural and synthetic pyrophyllites and assigned to hydroxides bonded to (Al-Al), (Al-Fe) and (Fe-Fe) cationic pairs. During this study, three samples were analysed by DTG to check the cis- or trans-vacant character of the layers and to determine the influence of this structural character on the OH-stretching band position in IR spectroscopy

Proposed therapeutic range of treosulfan in reduced toxicity pediatric allogeneic hematopoietic stem cell transplant conditioning: results from a prospective trial

Treosulfan is given off‐label in pediatric allogeneic hematopoietic stem cell transplant. This study investigated treosulfan's pharmacokinetics (PKs), efficacy, and safety in a prospective trial. Pediatric patients (n = 87) receiving treosulfan‐fludarabine conditioning were followed for at least 1 year posttransplant. PKs were described with a two‐compartment model. During follow‐up, 11 of 87 patients died and 12 of 87 patients had low engraftment (≤ 20% myeloid chimerism). For each increase in treosulfan area under the curve from zero to infinity (AUC(0‐∞)) of 1,000 mg hour/L the hazard ratio (95% confidence interval) for mortality increase was 1.46 (1.23–1.74), and the hazard ratio for low engraftment was 0.61 (0.36–1.04). A cumulative AUC(0‐∞) of 4,800 mg hour/L maximized the probability of success (> 20% engraftment and no mortality) at 82%. Probability of success with AUC(0‐∞) between 80% and 125% of this target were 78% and 79%. Measuring PK at the first dose and individualizing the third dose may be required in nonmalignant disease

History of malaria treatment as a predictor of subsequent subclinical parasitaemia: A cross-sectional survey and malaria case records from three villages in Pailin, western Cambodia

Background: Treatment of the sub-clinical reservoir of malaria, which may maintain transmission, could be an important component of elimination strategies. The reliable detection of asymptomatic infections with low levels of parasitaemia requires high-volume quantitative polymerase chain reaction (uPCR), which is impractical to conduct on a large scale. It is unknown to what extent sub-clinical parasitaemias originate from recent or older clinical episodes. This study explored the association between clinical history of malaria and subsequent sub-clinical parasitaemia. Methods: In June 2013 a cross-sectional survey was conducted in three villages in Pailin, western Cambodia. Demographic and epidemiological data and blood samples were collected. Blood was tested for malaria by high-volume qP

Raman scattering study of bulk and nanocrystalline PbMoO4 at high pressures

High-pressure Raman scattering measurements have been performed in wulfenite (PbMoO4) for both bulk and nanocrystalline powders up to 22 GPa. Our Raman scattering measurements evidence the phase transition from the tetragonal scheelite structure to the monoclinic M-fergusonite structure in both bulk and nanocrystalline powders above 10.8 and 13.4 GPa, respectively. The pressure dependences of the Raman active modes in both structures were compared and discussed based on our theoretical results obtained from lattice dynamics ab initio calculations. © 2012 American Institute of Physics.Financial support from the Spanish ConsoliderIngenio 2010 Program (Project No. CDS2007-00045) is acknowledged. The work was also supported by Spanish MICINN under Projects MAT2010-21270-C04-01/03/04 and from Vicerrectorado de Investigacion de la Universitat Politecnica de Valencia under Projects UPV2011-0914PAID-05-11 and UPV2011-0914 PAID-05-11. Supercomputer time has been provided by the Red Espanola de Supercomputacion (RES) and the MALTA cluster.Vilaplana Cerda, RI.; Gomis Hilario, O.; Manjón Herrera, FJ.; Rodríguez-Hernández, P.; Muñoz, A.; Errandonea, D.; Achary, S.... (2012). Raman scattering study of bulk and nanocrystalline PbMoO4 at high pressures. Journal of Applied Physics. 112:1035101-10351010. doi:10.1063/1.4765717S103510110351010112Pinnow, D. A., Van Uitert, L. G., Warner, A. W., & Bonner, W. A. (1969). LEAD MOLYBDATE: A MELT‐GROWN CRYSTAL WITH A HIGH FIGURE OF MERIT FOR ACOUSTO‐OPTIC DEVICE APPLICATIONS. Applied Physics Letters, 15(3), 83-86. doi:10.1063/1.1652917Coquin, G. A., Pinnow, D. A., & Warner, A. W. (1971). Physical Properties of Lead Molybdate Relevant to Acousto‐Optic Device Applications. Journal of Applied Physics, 42(6), 2162-2168. doi:10.1063/1.1660520Minowa, M., Itakura, K., Moriyama, S., & Ootani, W. (1992). Measurement of the property of cooled lead molybdate as a scintillator. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 320(3), 500-503. doi:10.1016/0168-9002(92)90945-zHernández-Uresti, D. B., Martínez-de la Cruz, A., & Torres-Martínez, L. M. (2011). Photocatalytic properties of PbMoO4 synthesized by co-precipitation method: organic dyes degradation under UV irradiation. Research on Chemical Intermediates, 38(3-5), 817-828. doi:10.1007/s11164-011-0420-xErrandonea, D., & Manjón, F. J. (2008). Pressure effects on the structural and electronic properties of ABX4 scintillating crystals. Progress in Materials Science, 53(4), 711-773. doi:10.1016/j.pmatsci.2008.02.001Manjon, F. J., Errandonea, D., Garro, N., Pellicer-Porres, J., López-Solano, J., Rodríguez-Hernández, P., … Muñoz, A. (2006). Lattice dynamics study of scheelite tungstates under high pressure II.PbWO4. Physical Review B, 74(14). doi:10.1103/physrevb.74.144112Errandonea, D., Pellicer-Porres, J., Manjón, F. J., Segura, A., Ferrer-Roca, C., Kumar, R. S., … Aquilanti, G. (2006). Determination of the high-pressure crystal structure ofBaWO4andPbWO4. Physical Review B, 73(22). doi:10.1103/physrevb.73.224103Manjón, F. J., Errandonea, D., Garro, N., Pellicer-Porres, J., Rodríguez-Hernández, P., Radescu, S., … Muñoz, A. (2006). Lattice dynamics study of scheelite tungstates under high pressure I.BaWO4. Physical Review B, 74(14). doi:10.1103/physrevb.74.144111Errandonea, D., Pellicer-Porres, J., Manjón, F. J., Segura, A., Ferrer-Roca, C., Kumar, R. S., … Aquilanti, G. (2005). High-pressure structural study of the scheelite tungstatesCaWO4andSrWO4. Physical Review B, 72(17). doi:10.1103/physrevb.72.174106Christofilos, D., Kourouklis, G. A., & Ves, S. (1995). A high pressure Raman study of calcium molybdate. Journal of Physics and Chemistry of Solids, 56(8), 1125-1129. doi:10.1016/0022-3697(95)00034-8Jayaraman, A., Wang, S. Y., Shieh, S. R., Sharma, S. K., & Ming, L. C. (1995). High-pressure Raman study of SrMoO4 up to 37 GPa and pressure-induced phase transitions. Journal of Raman Spectroscopy, 26(6), 451-455. doi:10.1002/jrs.1250260609Christofilos, D., Arvanitidis, J., Kampasakali, E., Papagelis, K., Ves, S., & Kourouklis, G. A. (2004). High pressure Raman study of BaMoO4. physica status solidi (b), 241(14), 3155-3160. doi:10.1002/pssb.200405234Panchal, V., Garg, N., & Sharma, S. M. (2006). Raman and x-ray diffraction investigations on BaMoO4under high pressures. Journal of Physics: Condensed Matter, 18(16), 3917-3929. doi:10.1088/0953-8984/18/16/002Errandonea, D., Kumar, R. S., Ma, X., & Tu, C. (2008). High-pressure X-ray diffraction study of SrMoO4 and pressure-induced structural changes. Journal of Solid State Chemistry, 181(2), 355-364. doi:10.1016/j.jssc.2007.12.010Errandonea, D., Santamaria-Perez, D., Achary, S. N., Tyagi, A. K., Gall, P., & Gougeon, P. (2011). High-pressure x-ray diffraction study of CdMoO4 and EuMoO4. Journal of Applied Physics, 109(4), 043510-043510-5. doi:10.1063/1.3553850Ganguly, B. N., & Nicol, M. (1977). Effect of hydrostatic pressure on the vibrational properties and the structure of SrWO4 and PbMoO4. Physica Status Solidi (b), 79(2), 617-622. doi:10.1002/pssb.2220790227Hazen, R. M., Finger, L. W., & Mariathasan, J. W. E. (1985). High-pressure crystal chemistry of scheelite-type tungstates and molybdates. Journal of Physics and Chemistry of Solids, 46(2), 253-263. doi:10.1016/0022-3697(85)90039-3Jayaraman, A., Batlogg, B., & VanUitert, L. G. (1985). Effect of high pressure on the Raman and electronic absorption spectra ofPbMoO4andPbWO4. Physical Review B, 31(8), 5423-5427. doi:10.1103/physrevb.31.5423Errandonea, D., Santamaria-Perez, D., Grover, V., Achary, S. N., & Tyagi, A. K. (2010). High-pressure x-ray diffraction study of bulk and nanocrystalline PbMoO4. Journal of Applied Physics, 108(7), 073518. doi:10.1063/1.3493048Syassen, K. (2008). Ruby under pressure. High Pressure Research, 28(2), 75-126. doi:10.1080/08957950802235640Kresse, G., & Joubert, D. (1999). From ultrasoft pseudopotentials to the projector augmented-wave method. Physical Review B, 59(3), 1758-1775. doi:10.1103/physrevb.59.1758Mujica, A., Rubio, A., Muñoz, A., & Needs, R. J. (2003). High-pressure phases of group-IV, III–V, and II–VI compounds. Reviews of Modern Physics, 75(3), 863-912. doi:10.1103/revmodphys.75.863Errandonea, D., & Manjón, F. J. (2009). On the ferroelastic nature of the scheelite-to-fergusonite phase transition in orthotungstates and orthomolybdates. Materials Research Bulletin, 44(4), 807-811. doi:10.1016/j.materresbull.2008.09.024Arora, A. K., Rajalakshmi, M., Ravindran, T. R., & Sivasubramanian, V. (2007). Raman spectroscopy of optical phonon confinement in nanostructured materials. Journal of Raman Spectroscopy, 38(6), 604-617. doi:10.1002/jrs.1684Cardona, M. (2004). Phonon widths versus pressure. High Pressure Research, 24(1), 17-23. doi:10.1080/08957950310001635819Cardona, M. (2004). Effects of pressure on the phonon–phonon and electron–phonon interactions in semiconductors. physica status solidi (b), 241(14), 3128-3137. doi:10.1002/pssb.200405202S. D. Ross, Inorganic Infrared and Raman Spectra (McGraw-Hill, Maidenhead, 1972), p. 414.Manjón, F. J., Errandonea, D., López-Solano, J., Rodríguez-Hernández, P., & Muñoz, A. (2009). Negative pressures in CaWO4 nanocrystals. Journal of Applied Physics, 105(9), 094321. doi:10.1063/1.311672

Uncertainty analysis using Bayesian Model Averaging: a case study of input variables to energy models and inference to associated uncertainties of energy scenarios

Background Energy models are used to illustrate, calculate and evaluate energy futures under given assumptions. The results of energy models are energy scenarios representing uncertain energy futures. Methods The discussed approach for uncertainty quantification and evaluation is based on Bayesian Model Averaging for input variables to quantitative energy models. If the premise is accepted that the energy model results cannot be less uncertain than the input to energy models, the proposed approach provides a lower bound of associated uncertainty. The evaluation of model-based energy scenario uncertainty in terms of input variable uncertainty departing from a probabilistic assessment is discussed. Results The result is an explicit uncertainty quantification for input variables of energy models based on well-established measure and probability theory. The quantification of uncertainty helps assessing the predictive potential of energy scenarios used and allows an evaluation of possible consequences as promoted by energy scenarios in a highly uncertain economic, environmental, political and social target system. Conclusions If societal decisions are vested in computed model results, it is meaningful to accompany these with an uncertainty assessment. Bayesian Model Averaging (BMA) for input variables of energy models could add to the currently limited tools for uncertainty assessment of model-based energy scenarios

Clinical Pharmacokinetics and Dose Recommendations for Posaconazole in Infants and Children.

OBJECTIVES: The objectives of this study were to investigate the population pharmacokinetics of posaconazole in immunocompromised children, evaluate the influence of patient characteristics on posaconazole exposure and perform simulations to recommend optimal starting doses. METHODS: Posaconazole plasma concentrations from paediatric patients undergoing therapeutic drug monitoring were extracted from a tertiary paediatric hospital database. These were merged with covariates collected from electronic sources and case-note reviews. An allometrically scaled population-pharmacokinetic model was developed to investigate the effect of tablet and suspension relative bioavailability, nonlinear bioavailability of suspension, followed by a step-wise covariate model building exercise to identify other important sources of variability. RESULTS: A total of 338 posaconazole plasma concentrations samples were taken from 117 children aged 5 months to 18 years. A one-compartment model was used, with tablet apparent clearance standardised to a 70-kg individual of 15 L/h. Suspension was found to have decreasing bioavailability with increasing dose; the estimated suspension dose to yield half the tablet bioavailability was 99 mg/m2. Diarrhoea and proton pump inhibitors were also associated with reduced suspension bioavailability. CONCLUSIONS: In the largest population-pharmacokinetic study to date in children, we have found similar covariate effects to those seen in adults, but low bioavailability of suspension in patients with diarrhoea or those taking concurrent proton pump inhibitors, which may in particular limit the use of posaconazole in these patients

Openness in participation, assessment, and policy making upon issues of environment and environmental health: a review of literature and recent project results

Issues of environment and environmental health involve multiple interests regarding e.g. political, societal, economical, and public concerns represented by different kinds of organizations and individuals. Not surprisingly, stakeholder and public participation has become a major issue in environmental and environmental health policy and assessment. The need for participation has been discussed and reasoned by many, including environmental legislators around the world. In principle, participation is generally considered as desirable and the focus of most scholars and practitioners is on carrying out participation, and making participation more effective. In practice also doubts regarding the effectiveness and importance of participation exist among policy makers, assessors, and public, leading even to undermining participatory practices in policy making and assessment

History of malaria treatment as a predictor of subsequent subclinical parasitaemia: a cross-sectional survey and malaria case records from three villages in Pailin, western Cambodia

Background Treatment of the sub-clinical reservoir of malaria, which may maintain transmission, could be an important component of elimination strategies. The reliable detection of asymptomatic infections with low levels of parasitaemia requires high-volume quantitative polymerase chain reaction (uPCR), which is impractical to conduct on a large scale. It is unknown to what extent sub-clinical parasitaemias originate from recent or older clinical episodes. This study explored the association between clinical history of malaria and subsequent sub-clinical parasitaemia. Methods In June 2013 a cross-sectional survey was conducted in three villages in Pailin, western Cambodia. Demographic and epidemiological data and blood samples were collected. Blood was tested for malaria by high-volume qPCR. Positive samples were analysed by nested PCR to determine the Plasmodium species. To identify previous episodes of malaria, case records were collected from village malaria workers and local health facilities and linked to study participants. Results Among 1343 participants, 40/122 (32.8 %) with a history of clinical malaria were parasitaemic during the cross-sectional survey, compared to 172/1221 (14.1 %) without this history (p Conclusions A clinical episode of vivax malaria was associated with subsequent sub-clinical parasitaemia. Treatment of P. vivax with artemisinin-based combination therapy without primaquine often resulted in recurrent episodes. Targeting individuals with a history of clinical malaria will be insufficient to eliminate the sub-clinical reservoir as they constitute a minority of parasitaemias.</p

Effect of Rare Earth Ions on the Properties of Composites Composed of Ethylene Vinyl Acetate Copolymer and Layered Double Hydroxides

BACKGROUND: The study on the rare earth (RE)-doped layered double hydroxides (LDHs) has received considerable attention due to their potential applications in catalysts. However, the use of RE-doped LDHs as polymer halogen-free flame retardants was seldom investigated. Furthermore, the effect of rare earth elements on the hydrophobicity of LDHs materials and the compatibility of LDHs/polymer composite has seldom been reported. METHODOLOGY/PRINCIPAL FINDINGS: The stearate sodium surface modified Ni-containing LDHs and RE-doped Ni-containing LDHs were rapidly synthesized by a coprecipitation method coupled with the microwave hydrothermal treatment. The influences of trace amounts of rare earth ions La, Ce and Nd on the amount of water molecules, the crystallinity, the morphology, the hydrophobicity of modified Ni-containing LDHs and the adsorption of modifier in the surface of LDHs were investigated by TGA, XRD, TEM, contact angle and IR, respectively. Moreover, the effects of the rare earth ions on the interfacial compatibility, the flame retardancy and the mechanical properties of ethylene vinyl acetate copolymer (EVA)/LDHs composites were also explored in detail. CONCLUSIONS/SIGNIFICANCE: S-Ni₀.₁MgAl-La displayed more uniform dispersion and better interfacial compatibility in EVA matrix compared with other LDHs. Furthermore, the S-Ni₀.₁MgAl-La/EVA composite showed the best fire retardancy and mechanical properties in all composites