150 research outputs found

    Modelling the adsorption of phenolic acids onto α\alpha,γ\gamma-alumina particles

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    International audienceAdsorption of three phenolic acids, namely parahydroxybenzoic acid (4-hydroxybenzoic acid, H2_2Phb), protocatechuic acid (3,4-dihydroxybenzoic acid, H2_2Proto) and gallic acid (3,4,5-trihydroxybenzoic acid, H2_2Gal) onto α\alpha,γ\gamma-Al2_2O3_3 particles was studied vs. ligand concentration at pH 5.0, and vs. pH. The oxide surface was characterized with both potentiometric titrations and electrophoretic measurements; a difference in the point of zero salt effect (PZSE) and the isoelectric point (IEP) was evidenced, which could be attributed to the presence of impurities or to the heterogeneity of the oxide. The potentiometric titration experiments lead to the determination of a PZSE of 8.5. Moreover, the particular shape of the curves were fitted in the framework of the constant capacitance model (CCM), using FITEQL 4.0 software, to determine the oxide parameters (protolytic properties and site density). The electrophoretic measurements were fitted in the framework of the double diffuse layer model (DLM) and an IEP of 9.5 was determined. The constant-pH isotherms of the acids were fitted using the CCM. Constant-pH isotherms of H2_2Gal and H2_2Proto onto the Al2_2O3_3 surface sites at pH 5 were similar. Two adsorption sites of different affinities were clearly evidenced for H2_2Gal and can also be proposed for H2_2Proto. H2_2Phb showed a lower affinity for the surface than the two other acids, as the logKsorb_{sorb} for H2_2Phb is one and a half time lower than the one for H2_2Proto when adsorption is described with one adsorption site. As expected for a carboxylic acid, adsorption of H2_2Phb decreased with pH and experimental data were well fitted using three adsorbed species \equivMOH2_2H2_2Phb+^+, \equivMHPhb^−, and \equivMPhb^−). Adsorption of H2_2Proto and H2_2Gal did not change significantly upon increasing pH, meaning that the different functional groups on the aromatic ring (carboxylate and phenolate) were involved in adsorption as pH increases. Dissolution of the oxide was also estimated by measuring the amount of soluble aluminum at pH 5. Increasing acid concentration promoted dissolution, especially for the low concentration range ([acid] < 3 mmol L1^{−1}), but higher acid concentration lowers the increase of the solubility increase, likely due to adsorption on surface of an aluminum-organic complex

    Complexation of europium(III) by hydroxybenzoic acids: a time-resolved luminescence spectroscopy study

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    International audienceComplexation of Eu(III) by two hydroxybenzoic acids, namely p-hydroxybenzoic acid (4 dihydroxybenzoic, HPhbH), and protocatechuic acid (3,4-dihydroxybenzoic, HProtoH2), is studied by time-resolved luminescence spectroscopy (TRLS) in mildly acidic solution. Comparable formation constants are determined at 0.1 mol/L NaCl for EuPhbH[2+] – log10β°(EuPhbH[2+]) = 2.18 ± 0.09 (1sigma) – and 0.01 mol/L NaCl for EuProtoH2[2+] – log10β°(EuProtoH2[2+]) = 2.72 ± 0.07 (1sigma). The stoichiometry and carboxylate complexation of the EuProtoH2[2+] complex is ascertained by varying both pH and ligand concentration. The luminescence decay time of EuPhbH[2+] (τ = 107 ± 5 µs) is comparable with that of Eu(H2O)n[3+] (τ = 110 ± 3 µs), suggesting that luminescence quenching processes compensate the expected increase in decay time due to the dehydration associated with complexation. For EuProtoH2[2+], the luminescence decay time is even shorter (τ = 20 ± 5 µs), evidencing intricate quenching processes

    PyMoosh : a comprehensive numerical toolkit for computing the optical properties of multilayered structures

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    We present PyMoosh, a Python-based simulation library designed to provide a comprehensive set of numerical tools allowing to compute essentially all optical characteristics of multilayered structures, ranging from reflectance and transmittance to guided modes and photovoltaic efficiency. Optimization tools are also included. PyMoosh is designed not just for research purposes, but also for use-cases in education. To this end, we have invested significant effort in ensuring user-friendliness and simplicity of the interface. PyMoosh has been developed in line with the principles of Open Science and taking into account the fact that multilayered structures are increasingly being used as a testing ground for optimization and deep learning approaches. We provide in this paper the theoretical basis at the core of PyMoosh, an overview of its capabilities, as well as a comparison between the different numerical methods implemented in terms of speed and stability. We are convinced such a versatile tool will be useful for the community in many ways

    Illustrated tutorial on global optimization in nanophotonics

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    Numerical optimization for the inverse design of photonic structures is a tool which is providing increasingly convincing results -- even though the wave nature of problems in photonics makes them particularly complex. In the meantime, the field of global optimization is rapidly evolving but is prone to reproducibility problems, making it harder to identify the right algorithms to use. This paper is thought as a tutorial on global optimization for photonic problems. We provide a general background on global optimization algorithms and a rigorous methodology for a physicist interested in using these tools -- especially in the context of inverse design. We suggest algorithms and provide explanations for their efficiency. We provide codes and examples as an illustration than can be run online, integrating quick simulation code and Nevergrad, a state-of-the-art benchmarking library. Finally, we show how physical intuition can be used to discuss optimization results and to determine whether the solutions are satisfactory or not

    The epidemiology of acne vulgaris in a multiethnic adolescent population from Rotterdam, the Netherlands:A cross-sectional study

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    Background: Although acne is a prevalent multifactorial inflammatory skin condition, few studies were performed in multiethnic populations. Objectives: To study the prevalence and determinants of acne in a multiethnic study at the start of puberty. Methods: This cross-sectional study is embedded in Generation R, a population-based prospective study from Rotterdam, the Netherlands. Three-dimensional facial photos at the center visit in 2016-2019 (of ∼13-year-olds) were used to grade acne severity using the Global Evaluation of the Acne Severity (GEA). Analyses were stratified by biological sex and explored through chi-square tests and multivariable ordinal logistic regression. Results: A total of 4561 children (51% girls) with a median age of 13.5 (IQR 13.3-13.6) were included. The visible acne prevalence (GEA 2-5) for girls vs boys was 62% vs 45% and moderate-to-severe acne (GEA 3-5) 14% vs 9%. Higher puberty stages (adjusted odds ratios: 1.38 [1.20-1.59] and 2.16 [1.86-2.51] for girls and boys, respectively) and darker skin colors V and VI (adjusted odds ratios: 1.90 [1.17-3.08] and 2.43 [1.67-3.56]) were associated with more severe acne in both sexes, and being overweight in boys (adjusted odds ratio: 1.58 [1.15-2.17]). Limitations: Cross-sectional design. Conclusions: Acne prevalence was high at the age of 13 years and was associated with advanced puberty, darker skin color, and weight status.</p

    The epidemiology of acne vulgaris in a multiethnic adolescent population from Rotterdam, the Netherlands:A cross-sectional study

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    Background: Although acne is a prevalent multifactorial inflammatory skin condition, few studies were performed in multiethnic populations. Objectives: To study the prevalence and determinants of acne in a multiethnic study at the start of puberty. Methods: This cross-sectional study is embedded in Generation R, a population-based prospective study from Rotterdam, the Netherlands. Three-dimensional facial photos at the center visit in 2016-2019 (of ∼13-year-olds) were used to grade acne severity using the Global Evaluation of the Acne Severity (GEA). Analyses were stratified by biological sex and explored through chi-square tests and multivariable ordinal logistic regression. Results: A total of 4561 children (51% girls) with a median age of 13.5 (IQR 13.3-13.6) were included. The visible acne prevalence (GEA 2-5) for girls vs boys was 62% vs 45% and moderate-to-severe acne (GEA 3-5) 14% vs 9%. Higher puberty stages (adjusted odds ratios: 1.38 [1.20-1.59] and 2.16 [1.86-2.51] for girls and boys, respectively) and darker skin colors V and VI (adjusted odds ratios: 1.90 [1.17-3.08] and 2.43 [1.67-3.56]) were associated with more severe acne in both sexes, and being overweight in boys (adjusted odds ratio: 1.58 [1.15-2.17]). Limitations: Cross-sectional design. Conclusions: Acne prevalence was high at the age of 13 years and was associated with advanced puberty, darker skin color, and weight status.</p

    Evolutionary algorithms converge towards evolved biological photonic structures

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    Nature features a plethora of extraordinary photonic architectures that have been optimized through natural evolution in order to more efciently refect, absorb or scatter light. While numerical optimization is increasingly and successfully used in photonics, it has yet to replicate any of these complex naturally occurring structures. Using evolutionary algorithms inspired by natural evolution and performing particular optimizations (maximize refection for a given wavelength, for a broad range of wavelength or maximize the scattering of light), we have retrieved the most stereotypical natural photonic structures. Whether those structures are Bragg mirrors, chirped dielectric mirrors or the gratings on top of Morpho butterfy wings, our results indicate how such regular structures might have spontaneously emerged in nature and to which precise optical or fabrication constraints they respond. Comparing algorithms show that recombination between individuals, inspired by sexual reproduction, confers a clear advantage that can be linked to the fact that photonic structures are fundamentally modular: each part of the structure has a role which can be understood almost independently from the rest. Such an in silico evolution also suggests original and elegant solutions to practical problems, as illustrated by the design of counter-intuitive anti-refective coatings for solar cells

    Volume 98 Issue 5, pp. 899-1054

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    ECOLOGY-EPIDEMIOLOGY-BEHAVIOR Increased Surfacing Behavior in Longnose Killifish Infected by Brain-Encysting Trematode. B. L. FREDENSBORG and A. N. LONGORIA - 899 Spatial Structure of Helminth Communities in the Golden Grey Mullet, Liza aurata (Actinopterygii: Mugilidae), From the Western Mediterranean. RAUL MIGUEZ-LOZANO, TRINIDAD V. PARDO-CARRANZA, ISABEL BLASCO-COSTA, and JUAN ANTONIO BALBUENA - 904 Hepatozoon Infection Prevalence in Four Snake Genera: Influence of Diet, Prey Parasitemia Levels, or Parasite Type? BEATRIZ TOME, JOAD P. M. C. MAIA, and D. JAMES HARRIS - 913 ECTOPARASITOLOGY Molecular Identification and Description of the Female of Nothoaspis reddelli (Ixodida: Argasidae) From a Cave in Southeastern Mexico. CARMEN GUZMAN-CORNEJO, RICARDO PAREDES-LEON, MARCELO B. LABRUNA, SANTIAGO NAVA, and JOSE M. VENZAL - 918 Prevalence of Hemoproteus iwa in Galapagos Great Frigatebirds (Fregata minor) and Their Obligate Fly Ectoparasite (01- Jersia spiniJera). IRIS I. LEVIN and PATRICIA G. PARKER - 924 Variable Microsatellite Loci for Population Genetic Analysis of Old World Monkey Lice (Pedicinus sp.). KATLYN SCHOLL, JULIE M. ALLEN, FABIAN H. LEENDERTZ, COLIN A. CHAPMAN, and DAVID L. REED - 930 FUNCTIONAL MORPHOLOGY Ultrastructural Study of Vitellogenesis of Aphallus tubarium (Rudolphi, 1819) Poche, 1926 (Digenea: Cryptogonimidae), an Intestinal Parasite of Dentex dentex (Pisces: Teleostei). SAMUEL GREANI, YANN QUILICHINI, JOSEPHINE FOATA, and BERNARD MARCHAND - 938 IMMUNOLOGY Seroprevalence of Toxoplasma gondii Infection in Domestic Horses in Durango State, Mexico. C. ALVARADO-ESQUIVEL, S. RODRIGUEZ-PENA, I. VILLENA, and J. P. DUBEY - 944 INVERTEBRATE-PARASITE RELATIONSHIPS Excystation Signals Do Not Isolate Gregarine Gene Pools: Experimental Excystation of Blabericola migrator Among 11 Species of Cockroaches. SHELBY M. STEELE, DEBRA T. CLOPTON, and RICHARD E. CLOPTON - 946 LIFE CYCLES-SURVEY A New Sarcocystis Species (Apicomplexa: Sarcocystidae) From the Rock Gecko Bunopus tuberculatus in Saudi Arabi. A. S. ABDEL-BAKI, H. M. ABDEL-HALEEM, and S. AL-QURAISHY - 951 A Retrospective Study of Abattoir Condemnation Due to Parasitic Infections: Economic Importance in Ahwaz, Southwestern Iran. HASSAN BORJI, MOHAMMAD AZIZZADEH, and MEHRAB KAMELLI - 954 Prevalence of Eimeria Infection in Yaks on the Qinghai-Tibet Plateau of China. HUI DONG, CHUNHUA LI, QIPING ZHAO, JING LI, HONGYU HAN, LIANLIAN JIANG, SHUNHAI ZHU, TING LI, CHUNLIN KONG, BING HUANG, and JINZHONG CAI - 958 Prevalence of Coccidial Infection in Dairy Cattle in Shanghai, China. HUI DONG, QIPING ZHAO, HONGYU HAN, LIANLIAN JIANG, SHUNHAI ZHU, TING LI, CHUNLIN KONG, and BING HUANG - 963 Genetic Sequence Data Identifies the Cercaria of Drepanocephalus spathans (Digenea: Echinostomatidae), a Parasite of the Double-Crested Cormorant (Phalacrocorax auritus), with Notes on Its Pathology in Juvenile Channel Catfish (Ictalurus punctatus). MATT J. GRIFFIN, LESTER H. KHOO, SYLVIE M. QUINIOU, MARY M. O\u27HEAR, LINDA M. POTE, TERRENCE E. GREENWAY, and DAVID J. WISE - 967 SYSTEMATICS-PHYLOGENETICS A New Species of Megalobatrachonema (Nematoda: Kathlaniidae) in Fojia bumui (Squamata: Scincidae) From Papua New Guinea. CHARLES R. BURSEY, STEPHEN R. GOLDBERG, and FRED KRAUS - 973 Two New Species of Schizorchis (Cestoda: Anoplocephalidae) From Leporids (Lagomorpha: Leporidae) in China. KUIZHENG CAI, JIALIN BAI, and SHIEN CHEN - 977 The Genus Guerrerostrongylus (Nematoda: Heligmonellidae) in Cricetid Rodents From the Atlantic Rain Forest of Misiones, Argentina: Emended Description of Guerrerostrongylus zetta (Travassos, 1937) and Description of a New Species. MARIA CELINA DIGIANI, JULIANA NOTARNICOLA, and GRACIELA T. NAVONE - 985 A New Microphallid (Digenea) Species From Lontra provocax (Mammalia: Mustelidae) From Freshwater Environments of Northwestern Patagonia (Argentina). VERONICA R. FLORES, NORMA L. BRUGNI, and CARLA M. POZZI - 992 Description of Riouxgolvania kapapkamui sp. n. (Nematoda: Muspiceoidea: Muspiceidae), a Peculiar Intradermal Parasite of Bats in Hokkaido, Japan. HIDEO HASEGAWA, MASAHIKO SATO, KISHIO MAEDA, and YOSHIKO MURAYAMA - 995 A New Species of Choleoeimeria (Apicomplexa: Eimeriidae) From Meller\u27s Chameleon, Trioceros melleri (Sauria: Chamaeleonidae). CHRIS T. McALLISTER - 1001 A New Species of Eimeria (Apicomplexa: Eimeriidae) From the Northern Myotis, Myotis septentrionalis (Chiroptera: Vespertilionidae), in Oklahoma. CHRIS T. McALLISTER, R. SCOTT SEVILLE, and ZACHARY P. ROEHRS - 1003 A New Spirurid (Nematoda) Parasite From Mormoopid Bats in Mexico. JORGE LUIS PERALTA-RODRIGUEZ, JUAN MANUEL CASPETA-MANDUJANO, and JOSE ANTONIO GUERRERO - 1006 THERAPEUTICS-DIAGNOSTICS Resistance of Rhipicephalus microplus to Amitraz and Cypermethrin in Tropical Cattle Farms in Veracruz, Mexico. AGUSTIN FERNANDEZ-SALAS, ROGER IVAN RODRIGUEZ-VIVAS, and MIGUEL ANGEL ALONSO-DIAZ - 1010 RESEARCH NOTES Seroprevalence Study on Theileria equi and Babesia caballi Antibodies in Horses From Central Province of Saudi Arabia. A. D. ALANAZI, M. S. ALYOUSIF, and M. M. HASSIEB - 1015 Influence of Rangelia vitalii (Apicomplexa: Piroplasmorida) on Copper, Iron and Zinc Bloodstream Levels in Experimentally Infected Dogs, ALEKSANDRO S, DA SILVA, RAQUELI T. FRANC;:A, MARCIO M. COSTA, CARLOS B. V. PAIM, FRANCINE C. PAIM, CLARISSA M. M. SANTOS, ERICO M. M. FLORES, TIAGO L. EILERS, CINTHIA M. MAZZANTI, SILVIA G. MONTEIRO, CARLOS H. DO AMARAL, and SONIA T. A. LOPES - 1018 Plagiorchis elegans (Trematoda) Induces Immune Response in an Incompatible Snail Host Biomphalaria glabrata (Pulmonata: Planorbidae). S. P. DAOUST, M. E. RAU, and J. D. McLAUGHLIN - 1021 Prevalence and Intensity of Fish-Borne Zoonotic Trematodes in Cultured Freshwater Fish From Rural and Urban Areas of Northern Vietnam. NGUYEN VAN DE, THANH HOA LE, and K. D. MURRELL - 1023 Details of the Paranephridial System of a Species of Prohyptiasmus (Cyclocoelidae: Hyptiasminae) From an American Coot, Fulica americana (Rallidae) in Oklahoma. NORMAN O. DRONEN, F. AGUSTIN JIMENEZ, and SCOTT L. GARDNER - 1026 Surface Ultrastructure of the Eggs of Malacopsylla grossiventris and Phthiropsylla agenoris (Siphonaptera: Malacopsyllidae). M. C. EZQUIAGA and M. LARES CHI - 1029 Prevalence of Ancylostoma braziliense in Cats in Three Northern Counties of Florida, United States. JANICE L. LIOTTA, KHUANCHAI N. KOOMPAPONG, JOSEPH P. YAROS, JOSEPH PRULLAGE, and DWIGHT D. BOWMAN - 1032 Obtaining an Isolate of Ancylostoma braziliense From Dogs Without the Need for Necropsy. JANICE L. LIOTTA, ALICE C. Y. LEE, SARP AKSEL, IBRAHIM ALKHALIFE, ALEJANDRO CRUZ-REYES, HEEJEONG YOUN, STEPHEN E. BIENHOFF, and DWIGHT D. BOWMAN - 1034 Obtaining an Isolate of Ancylostoma braziliense From Cats Without the Need for Necropsy. JANICE L. LIOTTA, ALICE C. Y. LEE, KHUANCHAI N. KOOMPAPONG, JOSEPH P. YAROS, JOSEPH PRULLAGE, MICHAEL A. ULRICH, and DWIGHT D. BOWMAN - 1037 Prevalence of Ancylostoma braziliense in Dogs From Alachua and Marion Counties, Florida, United States. JANICE L. LIOTTA, HEEJEONG YOUN, SARP AKSEL, STEPHEN E. BIENHOFF, and DWIGHT D. BOWMAN - 1039 Morphological Differentiation of Eggs of Ancylostoma caninum, Ancylostoma tubaeforme, and Ancylostoma braziliense From Dogs and Cats in the United States. ARACELI LUCIO-FORSTER, JANICE L. LIOTTA, JOSEPH P. YAROS, KAITLYN R. BRIGGS, HUSSNI O. MOHAMMED, and DWIGHT D. BOWMAN - 1041 Molecular and Immunological Characterization of a Novel 32-kDa Secreted Protein of Babesia microti. HIDEO OOKA, MOHAMAD A. TERKAWI, SHINUO CAO, GABRIEL ABOGE, YO UN-KYOUNG GOO, YUZI LUO, YAN LI, YOSHIFUMI NISHIKAWA, IKUO IGARASHI, and XUENAN XUAN - 1045 DNA Barcoding of Schistosome Cercariae Reveals a Novel Sub-Lineage within Schistosoma rodhaini From Ngamba Island Chimpanzee Sanctuary, Lake Victoria. C. J. STANDLEY and J. R. STOTHARD - 1049 Host Susceptibility Is Altered by Light Intensity After Exposure to Parasites. MICHELLE L. STEINAUER and KAITLIN M. BONNER - 1052 ANNOUNCEMENT: Change in Editorship - 903 ERRATUM - 91
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