Decoupling the adsorption mechanisms of arsenate at molecular level on modified cube-shaped sponge loaded superparamagnetic iron oxide nanoparticles.

In this study, a commercial cube-shaped open-celled cellulose sponge adsorbent was modified by in-situ co-precipitation of superparamagnetic iron oxide nanoparticles (SPION) and used to remove As(V) from aqueous solutions. Fe K-edge X-ray absorption spectroscopy (XAS) and TEM identified maghemite as the main iron phase of the SPION nanoparticles with an average size 13 nm. Batch adsorption experiments at 800 mg/L showed a 63% increase of adsorption capacity when loading 2.6 wt.% mass fraction of SPION in the cube-sponge. Experimental determination of the adsorption thermodynamic parameters indicated that the As(V) adsorption on the composite material is a spontaneous and exothermic process. As K-edge XAS results confirmed that the adsorption enhancement on the composite can be attributed to the nanoparticles loaded. In addition, adsorbed As(V) did not get reduced to more toxic As(III) and formed a binuclear corner-sharing complex with SPION. The advantageous cube-shape of the sponge-loaded SPION composite together with its high affinity and good adsorption capacity for As(V), good regeneration capability and the enhanced-diffusion attributed to its open-celled structure make this adsorbent a good candidate for industrial applications.

A New Sesquiterpene Essential Oil from the Native Andean Species Jungia rugosa Less (Asteraceae): Chemical Analysis, Enantiomeric Evaluation, and Cholinergic Activity.

As part of a project devoted to the phytochemical study of Ecuadorian biodiversity, new essential oils are systematically distilled and analysed. In the present work, Jungia rugosa Less (Asteraceae) has been selected and some wild specimens collected to investigate the volatile fraction. The essential oil, obtained from fresh leaves, was analysed for the first time in the present study. The chemical composition was determined by gas chromatography, coupled to mass spectrometry (GC-MS) for qualitative analysis, and to flame ionization detector (GC-FID) for quantitation. The calculation of relative response factors (RRF), based on combustion enthalpy, was carried out for each quantified component. Fifty-six compounds were identified and quantified in a 5% phenyl-polydimethylsiloxane non-polar column and 53 compounds in a polyethylene glycol polar column, including four undetermined compounds. The main feature of this essential oil was the exclusive sesquiterpenes content, both hydrocarbons (74.7% and 80.4%) and oxygenated (8.3% and 9.6%). Major constituents were: γ-curcumene (47.1% and 49.7%) and ß-sesquiphellandrene (17.0% and 17.9%), together with two abundant undetermined oxygenated sesquiterpenes, whose abundance was 6.7-7.2% and 4.7-3.3%, respectively. In addition, the essential oil was submitted to enantioselective evaluation in two ß-cyclodextrin-based enantioselective columns, determining the enantiomeric purity of a minor component (1S,2R,6R,7R,8R)-(+)-α-copaene. Finally, the AChE inhibition activity of the EO was evaluated in vitro. In conclusion, this volatile fraction is suitable for further investigation, according to two main lines: (a) the purification and structure elucidation of the major undetermined compounds, (b) a bio-guided fractionation, intended to investigate the presence of new sesquiterpene AChE inhibitors among the minor components.

Estimación de la edad cronológica en función de la mineralización del tercer molar inferior en población andina / Estimation of the chronological age based on the mineralization of the third lower molar in the andean population

RESUMEN Objetivo: Determinar el nivel de mineralización del tercer molar inferior de acuerdo a la edad cronológica mediante el método Demirjian en radiografías panorámicas digitales de pacientes andinos. Material y métodos: Se realizó un estudio correlacional analizando 706 radiografías panorámicas digitales en la Unidad Académica de Salud y Bienestar de la Universidad Católica de Cuenca Ecuador, en el período 2015-2016. Los pacientes tuvieron entre 6 y 22 años de edad. Se Evaluó un total de 1412 terceros molares (4.8 y 3.8). Resultados: Un primer análisis descriptivo mostró una correlación fuerte (Rho= 0,99) entre la edad cronológica y el nivel o grado de mineralización del tercer molar inferior. En ambas piezas estudiadas el inicio de la formación del tercer molar se dio en promedio a los 8,13 años y finalizaba a los 20,41 años. Los estadios que mostraron mayor coincidencia en ambos sexos y en ambas piezas fueron B, C, F, G y H y los estadios con menor coincidencia fueron los estadios A, D, E. Conclusiones: De acuerdo a los resultados podemos sugerir que el método Demirjian, es una herramienta útil para determinar la edad cronológica en base a la mineralización de los terceros molares, con un error de +/- 1.2 meses por lo que es posible ser usado para la estimación de la edad en evaluaciones forenses.

SUMMARY Objective: To determine the level of mineralization of the third lower molar according to chronological age using the Demirjian method in panoramic digital radiographies of Andean patients. Material and methods: A correlational study was carried out analyzing 706 digital panoramic radiographies in the Unidad Académica de Salud y Bienestar de la Universidad Católica de Cuenca Ecuador, in the period 2015-2016. The patients were between 6 and 22 years of age. A total of 1412 third molars (4.8 and 3.8) were evaluated. Results: A first descriptive analysis showed a strong correlation (Rho=0.99) between chronological age and the level or degree of mineralization of the lower third molar. In both studied pieces the beginning of the formation of the third molar was given in average at 8,13 years and finished at 20,41 years. The stages that showed greater coincidence in both sexes and in both pieces were B, C, F, G and H and the stages with less coincidence were the stages A, D, E. Conclusions: According to the results we can suggest that the Demirjian method is a useful tool to determine the chronological age based on the mineralization of the third molars, with an error of +/- 1.2 months so it is possible to be used for the estimation of the age in forensic evaluations.

Hipercementosis, una alteración de la estructura dentaria: recopilación bibliográfica / Hypercementosis, an alteration of the dental structure: bibliographic compilation

La hipercementosis se presenta como depósitos de cemento en la raíz de uno o más dientes. Siendo más frecuente en dientes que están sometidos a fuerzas de oclusión, particularmente en pacientes con enfermedad de Paget. El aumento de cemento se depositará en una banda que se encuentra situada alrededor del tercio apical de la raíz, es de ayuda útil realizar una evaluación radiográfi ca antes de una extracción dental (AU)

Hypercementosis occurs as cement deposits in the root of one or more teeth. Being more frequent in teeth that are subjected to occlusion forces or in patients with Paget's disease. The cement increase can be deposited in a band that can be found near the apical third of the root, it is a dental aid that a radiographic evaluation is made before a dental extraction (AU)

Assessment of toxicity and biodegradability on activated sludge of priority and emerging pollutants.

Several methods for evaluating the toxicity and biodegradability of hazardous pollutants (chlorinated compounds, chemical additives and pharmaceuticals) have been studied in this work. Different bioassays using representative bacteria of marine and terrestrial ecosystems such as Vibrio fischeri and Pseudomonas putida have been used to assess the ecotoxicity. Activated sludge was used to analyse the effect of those pollutants in a biological reactor of a sewage treatment plant (STP). The results demonstrate that none of the compounds is toxic to activated sludge, except ofloxacin to P. putida. The additives tested can be considered moderately toxic according to the more sensitive V. fischeri assays, whereas the EC50 values of the pharmaceuticals depend on the specific microorganism used in each test. Regarding the biodegradability, respirometric measurements were carried out for fast biodegradability assessment and the Zahn-Wellens test for inherent biodegradability. The evolution of the specific oxygen uptake rate (SOUR) showed that only diethyl phthalate was easily biodegradable and acetylsalicylic acid was partially biodegradable (98% and 65% degradation, respectively). The persistence of dichloromethane, ofloxacin and hidrochlorothiazide was confirmed along the 28 days of the Zahn-Wellens test whereas 1,1,1-trichloroethane showed inherent biodegradability (74% removal). Most of the chlorinated compounds, pharmaceuticals, bisphenol A and ethylenediaminetetraacetic acid were partially degraded in 28 d with total organic carbon (TOC) reduction ranging from 21% to 51%. Sulphamethoxazole showed certain biodegradation (50% removal) with TOC decrease around 31%, which indicates the formation of non-biodegradable by-products.

Radial versus longitudinal myocardial deformation from gray-scale echocardiography.

The objectives of this work are to evaluate a novel non-Doppler-based echocardiographic method that makes it possible to simultaneously obtain the radial and longitudinal components of myocardial velocity (V) and strain (S), and to assess whether left ventricular fiber architecture affects the net function of the myocardium. Previous reports state that differences in the estimation of regional function between septum and lateral walls can be related to the anatomic disposition of myocardial fibers. In this work we measure and compare in 21 healthy volunteers longitudinal and radial peak systolic velocity V (V(long), V(rad): cm/s), peak systolic strain S (S(long), S(rad): %) and time-to-peak S and V (T-Smax, T-V(max): ms) at the midsegments of the septal and lateral walls. Results show that V was higher, both in the radial and longitudinal components, in the lateral wall than in the septum (V(rad): 4.77 +/- 0.26 cm/s vs. 3.77 +/- 0.20 cm/s, p = 0.007; V(long): 5.60 +/- 0.48 cm/s vs. 4.13 +/- 0.11 cm/s, p = 0.01). Radial strain was higher in the septum (S(rad): 28.63 +/- 2.25% vs. 22.54 +/- 1.5%, p = 0.015), and longitudinal strain, in the lateral wall (S(long): -25.89 +/- 1.43% vs. -22.20 +/- 0.87%, p = 0.02). There was a significant delay in longitudinal T-Smax between the lateral and septal medial segments (mean: 14.5 ms; CI 95%: 0.3-28.6 ms; p = 0.04), with no difference in radial T-Smax (277.1 +/- 8.6 ms vs. 277.2 +/- 12.4 ms, p = 0.93). The assessment of regional myocardial function by this new method enables the simultaneous analysis of its radial and longitudinal components. These measurements correlate well with previous anatomical knowledge of the architecture of myocardial fibers, emphasizing its functional significance in regional myocardial function analysis.