Nickel and cobalt adsorption on hydroxyapatite: a study for the de-metalation of electronic industrial wastewaters

In the present study, the Ni(II) and Co(II) adsorption efficiency and selectivity, as well adsorption mechanisms on a stoichiometric hydroxyapatite (HAP) surface have been investigated. Characterization studies (N-2 adsorption/desorption and X-ray powder diffraction (XRPD) analyses) and adsorption tests under various operative conditions provided detailed information about the use of HAP in the de-metalation of wastewaters containing Ni and Co as polluted metal species. The sorption capacity of HAP has been evaluated by static batch adsorption tests varying initial concentration of Ni(II) and Co(II) species (from ca. 0.25 to 4.3mM), contact time (from 15min to 24h), and pH (from 4 to 9) operative parameters. Proposed mechanisms of adsorption of Ni(II) and Co(II) on HAP surface are ion-exchange and surface complexation; a partial contribution of chemical precipitation from bulk solution should be considered at pH 9. In addition, adsorption isotherms of Ni(II) and Co(II) on HAP have been collected at 30 degrees C and pH 4 and modeled by employing different equations. The maximum sorption capacities have been quantified as 0.317mmolgHAP-1 (18.6mggHAP-1) and 0.382mmolgHAP-1 (22.5mggHAP-1) for Ni(II) and Co(II), respectively. Selectivity to Co and Ni in the adsorption process on HAP has also been investigated; HAP has higher affinity towards Co than Ni species (Co:Ni=2.5:1, molar ratio)

Property and activity of molybdates dispersed on silica obtained from various synthetic procedures

The synthesis and characterization of several dispersed molybdena catalysts on silica support (MoO3-SiO2) prepared from a variety of precursors (Mo(VI)-acetylacetonate, oxo-peroxo Mo-species, hydrated ammonium heptamolybdate) and preparation methods (deposition of the Mo-phase on finite SiO2 support by aqueous and methanol impregnations, by adsorption, by oxo-peroxo route-like, and by one-step synthesis of MoO3-SiO2 system with molecular precursors) are presented. The molybdena concentration on silica was comprised in a large interval (1.5 - 14 wt%) depending on the preparation method which governed the Mo-loading on silica. Convenient comparisons among samples at similar Mo-concentration have been made discussing the morphologic-structural (XRD, XPS, UV-vis-DRS, and N2-adsorption) and physicochemical (TG-DTG, TPR, and n-butylamine-TPD) sample properties. Polymeric octahedral polymolybdate aggregates predominated in the samples prepared by aqueous and methanol impregnations, which were at high Mo-concentration. On the contrary, isolated Mo(VI) species in distorted Td symmetry predominated in the sample prepared by adsorption which was at very low Mo-concentration. The sample acidity was composed of a weak acidy site population, associated with the silica support, and a strong acid site population associated with the Mo-dispersed phase. Oxidation tests of formaldehyde, an oxygen-containing VOC (Volatile Organic Compound), were performed to determine the prevalent redox or acidic function of the Mo-species at the surface of the catalysts

Influence of the Nb/P ratio of acidic Nb-P-Si oxides on surface and catalytic properties

In this work, two acidic Nb-P-Si mixed oxide gel-derived materials characterized by Nb/P molar ratios equal to 2 (5Nb2.5 P) and 1 (2.5NbP) were investigated for their surface and bulk properties in relation with the catalytic performances in the fructose dehydration reaction. The structural characteristics of the studied samples and the changes occurring after water treatment and after reaction were investigated by 29Si and 31P solid state nuclear magnetic resonance (MAS-NMR) and X-ray photoelectron (XPS) spectroscopies, while the characterization of their acidic properties was performed by base (2-phenylethylamine) adsorption in liquid phase. MAS-NMR showed that the phosphorus remains firmly anchored into the siloxane matrix after exposure to cold water for 5Nb2.5 P sample and XPS confirmed the homogeneity of the sample composition. Both samples exhibited good intrinsic acidity and maintained significant effective acidity in polar-protic liquids; 2.5NbP manifested a double amount of acid sites compared to 5Nb2.5 P, when 2-phenylethylamine is used as probe. Fructose dehydration to 5-(hydroxymethyl)furfural (HMF) on the two gel-derived catalysts was performed in water and in water-isopropanol solution under mild conditions (130 °C) working in a recirculation reaction line comprising a tubular catalytic reactor. In water-isopropanol solution, the samples displayed good performances, as expected thanks to the lively effective acidity. Around 45-50% fructose conversion was attained on both samples, with selectivity to HMF equal to about 50% on 2.5NbP gel-derived catalyst. Recycling tests showed satisfactorily stable activity during three consecutive runs

European primary datasets of alien bacteria and viruses

Bacteria and viruses are a natural component of Earth biodiversity and play an essential role in biochemical and geological cycles. They may also pose problems outside their native range, where they can negatively impact on natural resources, wildlife, and human health. To address these challenges and develop sustainable conservation strategies, a thorough understanding of their invasion related- factors is needed: origin, country and year of introduction, and pathways dynamics. Yet, alien bacteria and viruses are underrepresented in invasion ecology studies, which limits our ability to quantify their impacts and address future introductions. This study provides primary datasets of alien bacteria and viruses of plants and animals present in the European environment. The datasets contain expert-revised data on 446 taxa and their invasion related- factors across terrestrial and aquatic environments. Taxa information are complemented with spatial occurrences. The datasets provide a basis for collaborative initiatives to improve the collection of alien bacteria and viruses' data, and a starting point for data-driven conservation practices

Hydroxyapatite-Based Electrodes for Metal Detection in Wastewater

Hydroxyapatite (HAp) is a biocompatible versatile material of formula Ca10(PO4)6(OH)2, insoluble in water within a wide pH range, chemically stable, relatively cheap and largely available. This mineral calcium phosphate has caught attention of scientists working in different fields of applied science, from medical engineering, to catalysis and pollution remediation. For environmental application, the absorbent nature of HAp is, probably, the most valuable feature. In particular, heavy metal retention ability is attributed to ion-exchange (Ca2+/ metal ion), surface adsorption/complexation, dissolution-precipitation mechanism, with single or combined action depending on the metal nature. Combining intrinsic affinities of HAp for metals with ductility of electrochemistry is a valuable route to develop monitoring systems and/or pollution remediation protocols. In doing so, the main obstacle for the exploitation of HAp as electrode materials is its electrical insulation nature. To overcome this limitation combination with conductive substrate is necessary, preparing either blends or composite materials. In this context, a series of carbon-containing hydroxyapatite composites (C-HAp) have been prepared by co-precipitation synthesis, by varying the conductive carbon source. The prepared materials have been characterized by various physical-chemical techniques (FT-IR spectroscopy, XRPD, TEM-EDX, N2-adsorption/desorption analyses) and the electrical conductivity has been determined as a function of the carbon source. The most promising C-HAp composites have been used as electrode substrates to quantify some of the common heavy metals found in waste water from urban and/or industrial sites (e.g., Pb2+, Cd2+, Cu2+, Zn2+) using cyclic and differential voltammetry techniques. The sensitivity of C-HAp electrodes was compared with that of glassy carbon ones, chosen as reference material. Different electrode geometries have been taken into consideration (C-HAp powder pressed into a cavity electrode, or free-standing C-HAp one). The work is still in progress and among possible alternative routes we are going to prepare directly HAp-based electrodes by in situ electrodeposition of calcium phosphate on low cost electron collectors such as steel. The final aim is to employ the HAp-based electrode as cathode in microbial fuel cells that could act as sensors for the on-line detection of metal traces in the treated wastes

Liquid Phase Direct Synthesis of H2O2 : Activity and Selectivity of Pd-Dispersed Phase on Acidic Niobia-Silica Supports

In this work, acidic niobia-silica (NbS, 4 1214 wt % Nb) materials used as supports of dispersed Pd particles (1.0 122.0 wt % Pd) have been prepared from different Nb-precursors (niobium ethoxide, NBE, and ammonium niobium oxalate, ANBO) and techniques (coprecipitation and deposition), characterized, and tested in the direct synthesis of H2O2 in water and methanol solvents. In particular, on a typical NbS sample, the evolution of morphology (by N2-adsorption 12desorption), crystalline-phase (by XRD), electronic structure (by UV 12vis-DRS), and surface acidity with time/temperature of treatment (350 12800 \ub0C for 4 12100 h) has been investigated. Surface acidity was measured by titrations with 2-phenylethylamine adsorption in various liquids: cyclohexane, for the intrinsic acidity, and water, methanol, and water 12methanol mixtures for the ef fective acidities. Direct H2O2 synthesis reaction was performed in semibatch slurry reactor with continuous feeding of the gaseous mixture (H2, O2, and N2), under pressure (5 7 103 kPa or 104 kPa) at 5 \ub0C in methanol or in water. In both solvents, reaction rates only little decreased with time on stream (ca. 5% of rate decrease after 4 h of reaction from initial rate of ca. 0.5 gH2O2\ub7(kgsolution\ub7min) 121, according with the slight Pd sintering observed by TEM images. Catalysts prepared by deposition of NBE on silica gave better performances than those prepared from ANBO. In general, selectivity to H2O2 in water and in methanol was observed to be similar; the unexpected good selectivity in water was due to the higher ef fective acid strengths of the catalytic surfaces in water than in methanol, as experimentally proven

Modulating the WNT pathway in Drosophila models of Cornelia de Lange Syndrome

Cornelia de Lange syndrome (CdLS) is a rare genetic disorder affecting neurodevelopment and the gastrointestinal, musculoskeletal systems. CdLS is caused by mutations within NIPBL, SMC1A, SMC3, RAD21, and HDAC8 genes. These genes codify for the cohesin complex, a multiprotein structure playing a role in chromatid adhesion, DNA repair and gene expression regulation. It has been demonstrated that a strong correlation exists between cohesin complex function and WNT signalling, an intracellular pathway involved in regulation of expression of several genes controlling cell division and embryonic development. Recently, it has been observed that chemical activation of the WNT pathway in nipblb-loss-of-function zebrafish embryos and in NIPBL-mutated patient fibroblasts rescued the adverse phenotype. Both embryos and fibroblasts present similar patterns of canonical WNT pathway alterations and cyclinD1 downregulation. Drosophila melanogaster is an inexpensive model to study CdLS and to screen in vivo for therapeutic compounds. Therefore, we have used flies strains mutated in Nipped-B and Hdac3 genes (respectively NIPBL and HDAC8 in humans) for assessing the existing correlation between cohesin complex and WNT pathway. Moreover, we have selected D. melanogaster mutants to screen for chemicals that revert the CdLS associated-phenotypes efficiently. In particular, we have tested several WNT activators and differences in modulating CdLS phenotypes will be discussed

Drosophila melanogaster as a model to study WNT pathway alteration in Cornelia de Lange Syndrome

Introduction: Cornelia de Lange syndrome (CdLS) is a rare genetic disorder affecting neurodevelopment, gastrointestinal and musculoskeletal systems. CdLS is caused by mutations within NIPBL, SMC1A, SMC3, RAD21, or HDAC8 genes. These genes codify for the cohesin complex, a multiprotein structure playing a role in chromatid adhesion, DNA repair and gene expression regulation. It has been demonstrated that a strong correlation exists between cohesin complex function and WNT signalling. Recently, it has been observed that chemical activation of the WNT pathway in nipblb-loss-of-function zebrafish embryos and in NIPBL-mutated patient fibroblasts rescued the adverse phenotype. Both embryos and fibroblasts present similar patterns of canonical WNT pathway alterations and CCND1 downregulation. Materials and Methods: Drosophila melanogaster is an inexpensive model to study CdLS and to screen in vivo for therapeutic compounds. Therefore, we have selected fly strains mutated in nipped-B and hdac3 genes (respectively NIPBL and HDAC8 in humans) for assessing the existing correlation between cohesin complex and WNT pathway and to screen for chemicals that revert the CdLS associated-phenotypes efficiently. Results: We have confirmed that mutated flies weight 5% less than wild type. Moreover, we have tested lithium chloride (LiCl) as WNT activator, demonstrating that 250mM is the highest concentration tolerated. Conclusions: Hence, we hypothesize that WNT pathway activation could improve mutant phenotype. We will be testing different doses of LiCl and other WNT activator to assess whether some of those chemical compounds could revert the syndrome-associated phenotype

Toward a clinical practice guide in pharmacogenomics testing for functional polymorphisms of drug-metabolizing enzymes. Gene/drug pairs and barriers perceived in Spain

The development of clinica lpractice recommendations or guidelines for the clinical use of biomarkers is an issue of great importance withr regard to adverse drug reactions.The poten-tial of pharmacogenomicbiomarkers has been extensively investigated in recent years.However,several barriers to implementing the use of pharmacogenomics testing exist.We conducted a survey among members of the Spanish Societies of Pharmacology and Clinical Pharmacology to obtain information about the perception of such barriers and to compare the perceptions of participants about the relative importance of majorgene/drug pairs.Of 11 potential barriers,the highest importance was attributed to lack of institutional support for pharmacogenomic stesting,and to the issues related to the lack of guidelines.Of the proposed gene/drug pairs the highest importance was assigned to HLA-B/abacavir, UGT1A1/irinotecan, and CYP2D6/tamoxifen.In this perspective article,we compare the relative importance of 29 gene/drugpairs in the Spanish study with that of the same pairs in the American Society for Clinical Pharmacology and Therapeutic sstudy,and we provide suggestions and areas of focus to develop a guide for clinical practice in pharmacogenomics testingThe work in the author’s laboratory is financed by Grants PS09/00943, PS09/00469, RETICS RIRAAF RD07/0064/0016, and CIBERehd from Instituto de Salud CarlosIII,Madrid, Spain, and by Grants GR10068 from Junta de Extremadura, Spain. Financed in part with FEDER funds from the European Unio

Molecular Etiology Disclosed by Array CGH in Patients With Silver–Russell Syndrome or Similar Phenotypes

Introduction: Silver-Russell syndrome (SRS) is an imprinting disorder primarily caused by genetic and epigenetic aberrations on chromosomes 11 and 7. SRS is a rare growth retardation disorder often misdiagnosed due to its heterogeneous and non-specific clinical features. The Netchine-Harbison clinical scoring system (NH-CSS) is the recommended tool for differentiating patients into clinical SRS or unlikely SRS. However, the clinical diagnosis is molecularly confirmed only in about 60% of patients, leaving the remaining substantial proportion of SRS patients with unknown genetic etiology. Materials and Methods: A cohort of 34 Italian patients with SRS or SRS-like features scored according to the NH-CSS and without any SRS-associated (epi)genetic alterations was analyzed by high-resolution array-based comparative genomic hybridization (CGH) in order to identify potentially pathogenic copy number variants (CNVs). Results and Discussion: In seven patients, making up 21% of the initial cohort, five pathogenic and two potentially pathogenic CNVs were found involving distinct genomic regions either previously associated with growth delay conditions (1q24.3-q25.3, 17p13.3, 17q22, and 22q11.2-q11.22) and with SRS spectrum (7p12.1 and 7p15.3-p14.3) or outlined for the first time (19q13.42), providing a better definition of reported and as yet unreported SRS overlapping syndromes. All the variants involve genes with a defined role in growth pathways, and for two genes mapping at 7p, IGF2BP3 and GRB10, the association with SRS turns out to be reinforced. The deleterious effect of the two potentially pathogenic variants, comprising GRB10 and ZNF331 genes, was explored by targeted approaches, though further studies are needed to validate their pathogenic role in the SRS etiology. In conclusion, we reconfirm the utility of performing a genome-wide scan to achieve a differential diagnosis in patients with SRS or similar features and to highlight novel chromosome alterations associated with SRS and growth retardation disorders