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1.
J Hum Evol ; 142: 102736, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32193025

RESUMEN

Despite the scarcity of fossil specimens of Theropithecus oswaldi in Eurasia, its presence out of Africa attests to the great dispersal of this Papionini genus during the Early Pleistocene. In the present study, we analyze the buccal dental microwear of T. oswaldi (T. o. leakeyi) fossil specimens from Cueva Victoria (Southeastern Spain). This analysis is the first characterization of the feeding ecology of T. oswaldi in Europe. The buccal microwear pattern of the molar and premolar teeth of T. oswaldi from Cueva Victoria shows great similarities to that observed for the extant frugivorous forest-dwelling Mandrillus sphinx and mangabeys (Cercocebus sp.)-both species adapted to durophagous dietary habits-while significantly different from that observed for the gramnivorous Theropithecus gelada. These results suggest that T. oswaldi from Cueva Victoria could have exploited both hard-shelled fruits or seeds and succulent fruits from open and forested Mediterranean ecosystems.


Asunto(s)
Dieta/veterinaria , Fósiles/anatomía & histología , Theropithecus/fisiología , Desgaste de los Dientes/veterinaria , Diente/anatomía & histología , Animales , Conducta Alimentaria , España , Desgaste de los Dientes/patología
2.
Arch Soc Esp Oftalmol ; 98(6): 325-328, 2023 Jun.
Artículo en Español | MEDLINE | ID: mdl-37252028

RESUMEN

Purpose: This study reports visual health during the COVID-19 pandemic in 2021 in Spain and Portugal, focusing on eye complaints and population habits. Material and methods: Cross-sectional survey through an online email invitation to patients attending ophthalmology clinics in Spain and Portugal from September to November 2021. Around 3833 participants offered valid anonymous responses in a questionnaire. Results: Sixty percent of respondents identified significant discomfort related to dry eye symptoms for increased screen time and lens fogging using facemasks. 81.6% of the participants used digital devices for more than 3 h per day and 40% for more than 8 h. In addition, 44% of participants referred to worsening near vision. The most frequent ametropias were myopia (40.2%) and astigmatism (36.7%). Parents considered eyesight the most important aspect of their children (87.2%). Conclusions: The results show the challenges for eye practices during the initial COVID-19 pandemic. Focusing on signs and symptoms that lead to ophthalmologic conditions is an essential concern, especially in our digital society highly dependent on vision. At the same time, the excessive use of digital devices during this pandemic has aggravated dry eye and myopia.

3.
Arch Soc Esp Oftalmol (Engl Ed) ; 98(6): 325-328, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37178785

RESUMEN

PURPOSE: This study reports visual health during the COVID-19 pandemic in 2021 in Spain and Portugal, focusing on eye complaints and population habits. MATERIAL AND METHODS: Cross-sectional survey through an online email invitation to patients attending ophthalmology clinics in Spain and Portugal from September to November 2021. Around 3833 participants offered valid anonymous responses in a questionnaire. RESULTS: Sixty percent of respondents identified significant discomfort related to dry eye symptoms for increased screen time and lens fogging using facemasks. 81.6% of the participants used digital devices for more than 3 h per day and 40% for more than 8 h. In addition, 44% of participants referred to worsening near vision. The most frequent ametropias were myopia (40.2%) and astigmatism (36.7%). Parents considered eyesight the most important aspect of their children (87.2%). CONCLUSIONS: The results show the challenges for eye practices during the initial COVID-19 pandemic. Focusing on signs and symptoms that lead to ophthalmologic conditions is an essential concern, especially in our digital society highly dependent on vision. At the same time, the excessive use of digital devices during this pandemic has aggravated dry eye and myopia.


Asunto(s)
COVID-19 , Síndromes de Ojo Seco , Miopía , Niño , Humanos , COVID-19/epidemiología , Pandemias , Portugal/epidemiología , España/epidemiología , Estudios Transversales , Miopía/epidemiología
4.
Inorg Chem ; 47(13): 5831-40, 2008 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-18517195

RESUMEN

A tin(IV) oxoalkoxo cluster with unprecedented architecture has been prepared and characterized by single-crystal X-ray diffraction. The cluster obeys the formula Sn 12O 8(OH) 4(OEt) 28(HOEt) 4 (1) and is based on an elongated centrosymmetric assembly of 12 six-coordinate tin centers, 28 peripheral ethoxy groups (terminal and bridging), 8 oxo bridges (mu2 and mu3), 4 hydroxy bridges (mu2), and 4 ethanol molecules that are all bound to tin atoms and interact strongly, through hydrogen bonds, with an ethoxy group located on a vicinal tin atom. This compound has also been fully characterized in solution by multinuclear 1D and 2D NMR, with all of its (119)Sn, (1)H, and (13)C NMR resonances assigned with respect to the structure. Altogether, the data allowed unambiguous location of the hydroxy groups. Information on the exchange of the ethoxy groups is also presented.

5.
7.
Dalton Trans ; 47(19): 6850-6859, 2018 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-29725678

RESUMEN

A simple and straightforward synthesis of N-heterocyclic carbene (NHC)-protected gold nanoparticles is derived from (benz)imidazolium-AuX4 complexes and NaBH4 only. The proposed method allows size tuning, from 3 to 6 nm, by adding (benz)imidazolium bromide. Changing the reducing agent to tBuNH2BH3 shifts the size range to ca. 6-12 nm. A one pot protocol is also reported from AuCl, (benz)imidazolium bromides and NaBH4, thereby providing an even more straightforward way of producing NHC-capped gold nanoparticles. In addition, X-ray photoelectron spectroscopy (XPS) is used to unambiguously evidence, on the nanoparticles, the covalent bond formed between the NHC and the surface gold atoms.

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