We reported the organic template-free synthesis of gold (Au) nanoparticles (NPs) supported on TiO
2
, SiO
2
, and Al
2
O
3
displaying uniform Au sizes and high dispersions over the supports. The ...Au-based catalysts were prepared by a deposition–precipitation method using urea as the precipitating agent. In the next step, the solvent-free oxidation of benzyl alcohol was investigated as model reaction using only 0.08–0.05 mol% of Au loadings and oxygen (O
2
) as the oxidant. Very high catalytic performances (TOF up to 443,624 h
−1
) could be achieved. Specifically, we investigated their catalytic activities, selectivity, and stabilities as well as the role of metal–support interactions over the performances. The conversion of the substrate was found to be associated with the nature of the employed support as the Au NPs presented similar sizes in all materials. A sub-stoichiometric amount of base was sufficient for the catalyst activation and the observation of the catalysts profile over the time enable insights on their recyclability performances. We believe this reported method represents a facile approach for the synthesis of uniform Au-supported catalysts displaying high performances.
Optical sensors based on lossy-mode resonances Del Villar, Ignacio; Arregui, Francisco J.; Zamarreño, Carlos R. ...
Sensors and actuators. B, Chemical,
March 2017, 2017-03-00, 20170301, Volume:
240
Journal Article
Peer reviewed
Open access
Lossy-mode resonance (LMR)–based optical sensing technology has emerged in the last two decades as a nanotechnological platform with very interesting and promising properties. LMR complements the ...metallic materials typically used in surface plasmon resonance (SPR)–based sensors, with metallic oxides and polymers. In addition, it enables one to tune the position of the resonance in the optical spectrum, to excite the resonance with both transverse electric (TE) and transverse magnetic (TM) polarized light, and to generate multiple resonances. The domains of application are numerous: as sensors for detection of refractive indices voltage, pH, humidity, chemical species, and antigens, as well as biosensors. This review will discuss the bases of this relatively new technology and will show the main contributions that have permitted the optimization of its performance to the point that the question arises as to whether LMR–based optical sensors could become the sensing platform of the near future.
Schistosoma mansoni, efficacy of praziquantel in patients who had been unsuccessfully treated with hycanthone and/or oxamniquine, strains isolated from these patients were resistant to oxamniquine ...and hycanthone but sensitive to niridazole and praziquantel
Gelatinous zooplankton (Cnidaria, Ctenophora, and Urochordata, namely, Thaliacea) are ubiquitous members of plankton communities linking primary production to higher trophic levels and the deep ocean ...by serving as food and transferring “jelly‐carbon” (jelly‐C) upon bloom collapse. Global biomass within the upper 200 m reaches 0.038 Pg C, which, with a 2–12 months life span, serves as the lower limit for annual jelly‐C production. Using over 90,000 data points from 1934 to 2011 from the Jellyfish Database Initiative as an indication of global biomass (JeDI: http://jedi.nceas.ucsb.edu, http://www.bco‐dmo.org/dataset/526852), upper ocean jelly‐C biomass and production estimates, organism vertical migration, jelly‐C sinking rates, and water column temperature profiles from GLODAPv2, we quantitatively estimate jelly‐C transfer efficiency based on Longhurst Provinces. From the upper 200 m production estimate of 0.038 Pg C year−1, 59–72% reaches 500 m, 46–54% reaches 1,000 m, 43–48% reaches 2,000 m, 32–40% reaches 3,000 m, and 25–33% reaches 4,500 m. This translates into ~0.03, 0.02, 0.01, and 0.01 Pg C year−1, transferred down to 500, 1,000, 2,000, and 4,500 m, respectively. Jelly‐C fluxes and transfer efficiencies can occasionally exceed phytodetrital‐based sediment trap estimates in localized open ocean and continental shelves areas under large gelatinous blooms or jelly‐C mass deposition events, but this remains ephemeral and transient in nature. This transfer of fast and permanently exported carbon reaching the ocean interior via jelly‐C constitutes an important component of the global biological soft‐tissue pump, and should be addressed in ocean biogeochemical models, in particular, at the local and regional scale.
Key Points
Gelatinous zooplankton link primary production to higher trophic levels and the deep ocean by serving as food and transferring jelly‐C
From global jelly‐C production (0.038 Pg C year−1) 59–72% reaches 500 m, 46–54% to 1,000 m, 43–48% to 2,000 m, 32–40% to 3,000 m, 25–33% to 4,500 m
The jelly‐C flux reaching the ocean interior is larger than anticipated for an important component of the global biological soft‐tissue pump
Parkinson's disease is now considered a complex, multi-peptide, central, and peripheral nervous system disorder with considerable clinical heterogeneity. Non-motor symptoms play a key role in the ...trajectory of Parkinson's disease, from prodromal premotor to end stages. To understand the clinical heterogeneity of Parkinson's disease, this study used cluster analysis to search for subtypes from a large, multi-center, international, and well-characterized cohort of Parkinson's disease patients across all motor stages, using a combination of cardinal motor features (bradykinesia, rigidity, tremor, axial signs) and, for the first time, specific validated rater-based non-motor symptom scales. Two independent international cohort studies were used: (a) the validation study of the Non-Motor Symptoms Scale (
= 411) and (b) baseline data from the global Non-Motor International Longitudinal Study (
= 540).
-means cluster analyses were performed on the non-motor and motor domains (domains clustering) and the 30 individual non-motor symptoms alone (symptoms clustering), and hierarchical agglomerative clustering was performed to group symptoms together. Four clusters are identified from the domains clustering supporting previous studies: mild, non-motor dominant, motor-dominant, and severe. In addition, six new smaller clusters are identified from the symptoms clustering, each characterized by clinically-relevant non-motor symptoms. The clusters identified in this study present statistical confirmation of the increasingly important role of non-motor symptoms (NMS) in Parkinson's disease heterogeneity and take steps toward subtype-specific treatment packages.
The measurement of chemical and biomedical parameters can take advantage of the features exclusively offered by optical fibre: passive nature, electromagnetic immunity and chemical stability are some ...of the most relevant ones. The small dimensions of the fibre generally require that the sensing material be loaded into a supporting matrix whose morphology is adjusted at a nanometric scale. Thanks to the advances in nanotechnology new deposition methods have been developed: they allow reagents from different chemical nature to be embedded into films with a thickness always below a few microns that also show a relevant aspect ratio to ensure a high transduction interface. This review reveals some of the main techniques that are currently been employed to develop this kind of sensors, describing in detail both the resulting supporting matrices as well as the sensing materials used. The main objective is to offer a general view of the state of the art to expose the main challenges and chances that this technology is facing currently.
The present study examines the contribution of mothers’ well-being, parenting expectations, and parenting attitudes (BEC) to their children’s school achievement. Its aim was to examine if these ...contributions may help to explain the unclear relationships between parenting involvement and children’s school achievement. A total of 621 mothers and their children from first, second, and third grade participated in the study. In the sample of children, 322 were females and 299 were males. They were divided in five groups of similar size, each group representing a different city of origin in Mexico. Using cluster analysis, the authors found two groups of mothers with low or high scores on the measures tested. These groups, named low or high BEC, showed differences in the distributions of socioeconomic variables. Based on that finding, six new groups were formed taking into account such socioeconomic influences. It was found that three factors, family income, mothers’ schooling, and BEC were related directly to children’s school achievement, but they were poorly related to measures of parenting involvement, with the exception of promotion of reading in children. The findings of this study suggest that other factors rather than the traditional concept of parental involvement have differential effects on children’s academic achievement
Research to identify plant bioactive compounds led to the evolution of extraction methods. This study optimized ultrasound-assisted extraction (UAE) and microwave-assisted extraction (MAE) to extract ...the flavonoids of Croton grewioides Baill. species contributing to characterize the polar extract profile and understand the antioxidant potential of these plant constituents. The use of experimental design and statistical treatments enabled the determination of the ideal conditions for each technique. The extracts of five accessions of C. grewioides were obtained under the optimized extraction conditions and were analyzed using ultra high-resolution mass spectrometry (FT-Orbitrap MS) operating at negative ionization mode for flavonoids detection. The accurate experimental mass obtained to the main compounds was used to attribute the molecular formula. Chemical structures of the main compounds detected were proposed using structure data bases. Chemometric analysis were performed with two FT-Orbitrap MS spectra samples using the identified metabolites and, the antioxidant activity data, showing that for this species the MAE was most effective in extracting the antioxidant compounds. It was possible to propose the structures for forty compounds in the C. grewioides extracts, demonstrating the excellent performance of the FT-Orbitrap MS in providing information on the chemical profile of polar compounds in plant extracts.
This research focuses on the study of the ruins of a large building known as "El Torreón" (the Tower), belonging to the Ulaca
(Solosancho, Province of Ávila, Spain). Different remote sensing and ...geophysical approaches have been used to fulfil this objective, providing a better understanding of the building's functionality in this town, which belongs to the Late Iron Age (ca. 300-50 BCE). In this sense, the outer limits of the ruins have been identified using photogrammetry and convergent drone flights. An additional drone flight was conducted in the surrounding area to find additional data that could be used for more global interpretations. Magnetometry was used to analyze the underground bedrock structure and ground penetrating radar (GPR) was employed to evaluate the internal layout of the ruins. The combination of these digital methodologies (surface and underground) has provided a new perspective for the improved interpretation of "El Torreón" and its characteristics. Research of this type presents additional guidelines for better understanding of the role of this structure with regards to other buildings in the Ulaca
. The results of these studies will additionally allow archaeologists to better plan future interventions while presenting new data that can be used for the interpretation of this archaeological complex on a larger scale.
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