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1.
Circ Res ; 128(9): 1344-1370, 2021 04 30.
Artículo en Inglés | MEDLINE | ID: mdl-33914601

RESUMEN

Calcific aortic valve disease is dramatically increasing in global burden, yet no therapy exists outside of prosthetic replacement. The increasing proportion of younger and more active patients mandates alternative therapies. Studies suggest a window of opportunity for biologically based diagnostics and therapeutics to alleviate or delay calcific aortic valve disease progression. Advancement, however, has been hampered by limited understanding of the complex mechanisms driving calcific aortic valve disease initiation and progression towards clinically relevant interventions.


Asunto(s)
Estenosis de la Válvula Aórtica/etiología , Válvula Aórtica/citología , Válvula Aórtica/patología , Calcinosis/etiología , Progresión de la Enfermedad , Células Endoteliales/fisiología , Válvula Aórtica/inmunología , Válvula Aórtica/fisiología , Estenosis de la Válvula Aórtica/diagnóstico , Estenosis de la Válvula Aórtica/inmunología , Estenosis de la Válvula Aórtica/terapia , Calcinosis/diagnóstico , Calcinosis/inmunología , Calcinosis/terapia , Moléculas de Adhesión Celular/metabolismo , Homeostasis , Humanos , Sistema Inmunológico/fisiología , Mediadores de Inflamación/metabolismo , Óxido Nítrico/biosíntesis , Óxido Nítrico Sintasa de Tipo III/metabolismo , Pronóstico , Especies Reactivas de Oxígeno , Factores de Riesgo , Vasculitis/etiología
2.
Nat Mater ; 20(1): 93-99, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33106648

RESUMEN

Metal-organic frameworks (MOFs) offer disruptive potential in micro- and optoelectronics because of the unique properties of these microporous materials. Nanoscale patterning is a fundamental step in the implementation of MOFs in miniaturized solid-state devices. Conventional MOF patterning methods suffer from low resolution and poorly defined pattern edges. Here, we demonstrate the resist-free, direct X-ray and electron-beam lithography of MOFs. This process avoids etching damage and contamination and leaves the porosity and crystallinity of the patterned MOFs intact. The resulting high-quality patterns have excellent sub-50-nm resolution, and approach the mesopore regime. The compatibility of X-ray and electron-beam lithography with existing micro- and nanofabrication processes will facilitate the integration of MOFs in miniaturized devices.

3.
Proc Natl Acad Sci U S A ; 115(4): E648-E657, 2018 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-29311304

RESUMEN

Anthropogenic noise is a pervasive pollutant that decreases environmental quality by disrupting a suite of behaviors vital to perception and communication. However, even within populations of noise-sensitive species, individuals still select breeding sites located within areas exposed to high noise levels, with largely unknown physiological and fitness consequences. We use a study system in the natural gas fields of northern New Mexico to test the prediction that exposure to noise causes glucocorticoid-signaling dysfunction and decreases fitness in a community of secondary cavity-nesting birds. In accordance with these predictions, and across all species, we find strong support for noise exposure decreasing baseline corticosterone in adults and nestlings and, conversely, increasing acute stressor-induced corticosterone in nestlings. We also document fitness consequences with increased noise in the form of reduced hatching success in the western bluebird (Sialia mexicana), the species most likely to nest in noisiest environments. Nestlings of all three species exhibited accelerated growth of both feathers and body size at intermediate noise amplitudes compared with lower or higher amplitudes. Our results are consistent with recent experimental laboratory studies and show that noise functions as a chronic, inescapable stressor. Anthropogenic noise likely impairs environmental risk perception by species relying on acoustic cues and ultimately leads to impacts on fitness. Our work, when taken together with recent efforts to document noise across the landscape, implies potential widespread, noise-induced chronic stress coupled with reduced fitness for many species reliant on acoustic cues.


Asunto(s)
Corticosterona/sangre , Aptitud Genética , Comportamiento de Nidificación , Ruido/efectos adversos , Pájaros Cantores/sangre , Animales , Tamaño Corporal , Plumas/crecimiento & desarrollo , Femenino
4.
Angew Chem Int Ed Engl ; 60(49): 25668-25673, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34478224

RESUMEN

Film deposition and high-resolution patterning of ionic liquids (ILs) remain a challenge, despite a broad range of applications that would benefit from this type of processing. Here, we demonstrate for the first time the chemical vapor deposition (CVD) of ILs. The IL-CVD method is based on the formation of a non-volatile IL through the reaction of two vaporized precursors. Ionogel micropatterns can be easily obtained via the combination of IL-CVD and standard photolithography, and the resulting microdrop arrays can be used as microreactors. The IL-CVD approach will facilitate leveraging the properties of ILs in a range of applications and microfabricated devices.

5.
Ecol Appl ; 27(1): 260-273, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-28052511

RESUMEN

Birds breeding in heterogeneous landscapes select nest sites by cueing in on a variety of factors from landscape features and social information to the presence of natural enemies. We focus on determining the relative impact of anthropogenic noise on nest site occupancy, compared to amount of forest cover, which is known to strongly influence the selection process. We examine chronic, industrial noise from natural gas wells directly measured at the nest box as well as site-averaged noise, using a well-established field experimental system in northwestern New Mexico. We hypothesized that high levels of noise, both at the nest site and in the environment, would decrease nest box occupancy. We set up nest boxes using a geospatially paired control and experimental site design and analyzed four years of occupancy data from four secondary cavity-nesting birds common to the Colorado Plateau. We found different effects of noise and landscape features depending on species, with strong effects of noise observed in breeding habitat selection of Myiarchus cinerascens, the Ash-throated Flycatcher, and Sialia currucoides, the Mountain Bluebird. In contrast, the amount of forest cover less frequently explained habitat selection for those species or had a smaller standardized effect than the acoustic environment. Although forest cover characterization and management is commonly employed by natural resource managers, our results show that characterizing and managing the acoustic environment should be an important tool in protected area management.


Asunto(s)
Ecosistema , Comportamiento de Nidificación , Ruido , Industria del Petróleo y Gas , Passeriformes/fisiología , Animales , Bosques , New Mexico
6.
Phytochem Anal ; 24(5): 446-52, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23839937

RESUMEN

INTRODUCTION: Grapes are one of the most important fruit crops in the world. The quality of red grape berries greatly depends on skin colour, mainly due to the anthocyanin profile. Today, the American Vitis species have the greatest potential for breeding work. They have multiple resistance properties in comparison with Vitis vinifera but little is known about their anthocyanin content. OBJECTIVE: To determine the anti-oxidant properties and anthocyanin profile of two American species, Vitis candicans and Vitis doaniana, by using LC-MS(n) and LC-NMR. METHODS: Grape extracts were prepared by extraction of berry skins with acidified methanol. The complete structure elucidation of the individual anthocyanins was performed with LC-MS(n) , LC-NMR and NMR experiments. Individual anthocyanins in the extracts were quantified by using malvidin glucoside as external standard. The anti-oxidant activities of grape skin extracts were evaluated by using 1,1-diphenyl-2-picrylhydrazyl (DPPH•) radical scavenging and oxygen radical absorbance capacity (ORAC) assays. RESULTS: By using LC-MS(n) and LC-NMR experiments, 30 anthocyanins were identified and quantified in the two Vitis species, including two new cis-p-coumaroyl derivatives. Vitis candicans and V. doaniana showed significant differences in their anthocyanin profile. These two Vitis species possess low-to-medium anti-oxidant activities in comparison with V. vinifera. CONCLUSION: The profiles of 30 anthocyanins were established unambiguously in two American Vitis species.


Asunto(s)
Antocianinas/análisis , Antioxidantes/análisis , Vitis/química , Antocianinas/farmacología , Antioxidantes/farmacología , Cromatografía Líquida de Alta Presión , Depuradores de Radicales Libres/análisis , Depuradores de Radicales Libres/farmacología , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Especificidad de la Especie , Vitis/clasificación
7.
Proc Biol Sci ; 279(1739): 2727-35, 2012 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-22438504

RESUMEN

Noise pollution is a novel, widespread environmental force that has recently been shown to alter the behaviour and distribution of birds and other vertebrates, yet whether noise has cumulative, community-level consequences by changing critical ecological services is unknown. Herein, we examined the effects of noise pollution on pollination and seed dispersal and seedling establishment within a study system that isolated the effects of noise from confounding stimuli common to human-altered landscapes. Using observations, vegetation surveys and pollen transfer and seed removal experiments, we found that effects of noise pollution can reverberate through communities by disrupting or enhancing these ecological services. Specifically, noise pollution indirectly increased artificial flower pollination by hummingbirds, but altered the community of animals that prey upon and disperse Pinus edulis seeds, potentially explaining reduced P. edulis seedling recruitment in noisy areas. Despite evidence that some ecological services, such as pollination, may benefit indirectly owing to noise, declines in seedling recruitment for key-dominant species such as P. edulis may have dramatic long-term effects on ecosystem structure and diversity. Because the extent of noise pollution is growing, this study emphasizes that investigators should evaluate the ecological consequences of noise alongside other human-induced environmental changes that are reshaping human-altered landscapes worldwide.


Asunto(s)
Aves/fisiología , Ruido , Peromyscus/fisiología , Pinus/fisiología , Polinización , Animales , Conducta Animal , Ecosistema , Industrias , Plantones , Semillas
8.
Proc Biol Sci ; 278(1714): 2025-31, 2011 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-21123268

RESUMEN

Anthropogenic noise is prevalent across the globe and can exclude birds from otherwise suitable habitat and negatively influence fitness; however, the mechanisms responsible for species' responses to noise are not always clear. One effect of noise is a reduction in effective acoustic communication through acoustic masking, yet some urban songbirds may compensate for masking by noise through altering their songs. Whether this vocal flexibility accounts for species persistence in noisy areas is unknown. Here, we investigated the influence of noise on habitat use and vocal frequency in two suboscine flycatchers using a natural experiment that isolated effects of noise from confounding stimuli common to urban habitats. With increased noise exposure, grey flycatcher (Empidonax wrightii) occupancy declined, but vocal frequency did not change. By contrast, ash-throated flycatcher (Myiarchus cinerascens) occupancy was uninfluenced by noise, but individuals in areas with greater noise amplitudes vocalized at a higher frequency, although the increase (≈200 kHz) may only marginally improve communication and may represent a secondary effect from increased vocal amplitude. Even so, the different flycatcher behavioural responses suggest that signal change may help some species persist in noisy areas and prompt important questions regarding which species will cope with an increasingly noisy world.


Asunto(s)
Estimulación Acústica , Passeriformes/fisiología , Vocalización Animal , Animales , Actividades Humanas , Humanos , New Mexico , Ruido , Espectrografía del Sonido
9.
Biol Lett ; 7(6): 850-2, 2011 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-21613284

RESUMEN

Anthropogenic noise, now common to many landscapes, can impair acoustic communication for many species, yet some birds compensate for masking by noise by altering their songs. The phylogenetic distribution of these noise-dependent signal adjustments is uncertain, and it is not known whether closely related species respond similarly to noise. Here, we investigated the influence of noise on habitat occupancy rates and vocal frequency in two congeneric vireos with similar song features. Noise exposure did not influence occupancy rates for either species, yet song features of both changed, albeit in different ways. With increases in noise levels, plumbeous vireos (Vireo plumbeus) sang shorter songs with higher minimum frequencies. By contrast, grey vireos (Vireo vicinior) sang longer songs with higher maximum frequencies. These findings support the notion that vocal plasticity may help some species occupy noisy areas, but because there were no commonalities among the signal changes exhibited by these closely related birds, it may be difficult to predict how diverse species may modify their signals in an increasingly noisy world.


Asunto(s)
Ruido , Pájaros Cantores/fisiología , Vocalización Animal , Animales , Masculino , New Mexico , Filogenia , Pájaros Cantores/clasificación , Espectrografía del Sonido/veterinaria , Especificidad de la Especie
10.
Dalton Trans ; 50(20): 6784-6788, 2021 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-33969844

RESUMEN

Chemical vapor deposition of metal-organic frameworks (MOF-CVD) will facilitate the integration of porous and crystalline coatings in electronic devices. In the two-step MOF-CVD process, a precursor layer is first deposited and subsequently converted to a MOF through exposure to linker vapor. We herein report the impact of different metal oxide and metalcone layers as precursors for zeolitic imidazolate framework ZIF-8 films.

11.
Adv Mater ; 33(17): e2006993, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33733524

RESUMEN

Thin films of crystalline and porous metal-organic frameworks (MOFs) have great potential in membranes, sensors, and microelectronic chips. While the morphology and crystallinity of MOF films can be evaluated using widely available techniques, characterizing their pore size, pore volume, and specific surface area is challenging due to the low amount of material and substrate effects. Positron annihilation lifetime spectroscopy (PALS) is introduced as a powerful method to obtain pore size information and depth profiling in MOF films. The complementarity of this approach to established physisorption-based methods such as quartz crystal microbalance (QCM) gravimetry, ellipsometric porosimetry (EP), and Kr physisorption (KrP) is illustrated. This comprehensive discussion on MOF thin film porosimetry is supported by experimental data for thin films of ZIF-8.

12.
Talanta ; 215: 120910, 2020 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-32312454

RESUMEN

Chemical vapor deposition of MOFs (MOF-CVD) has been used to coat solid-phase microextraction (SPME) fibers with ZIF-8, by exposing ZnO layers to the linker vapor (2-methylimidazole). This ZIF-8 coating has been used as a seed layer in a following solvothermal MOF growth step in order to increase the ZIF-8 thickness. The combined MOF-CVD and solvothermal growth of ZIF-8 on the fibers result in a thickness of ~3 µm, with adequate thermal stability, and mechanical integrity when tested with methanol and acetonitrile ultrasonic treatments. The fibers have been evaluated in direct immersion mode using gas chromatography and flame ionization detection (GC-FID), for a group of target analytes including three polycyclic aromatic hydrocarbons (PAHs) and five personal care products (PCPs). The optimized conditions of the SPME-GC-FID methods include low amount of aqueous sample (5 mL), stirring for 45 min at 35 °C, and desorption at 280 °C for 5 min. The method presents limits of detection down to 0.6 µg L-1; intra-day, inter-day and inter-batch relative standard deviation values lower than 16%, 19%, and 23%, respectively; and a lifetime higher than 70 cycles.

13.
Plant Foods Hum Nutr ; 64(2): 94-101, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19424801

RESUMEN

Cereals provide a good source of dietary fibre and other important compounds with nutritional potential, such as phenolic compounds, antioxidants, minerals and vitamins. Although native Andean cereals are known to have high nutritional value, their minor components have not been studied thoroughly. In this study, two varieties of a native Andean crop, kañiwa (Chenopodium pallidicaule), were investigated as sources of dietary fibre and specific antioxidant compounds. Two products, an extrudate and bran, were also prepared and their functional properties and bioactive compounds were determined. Both varieties were rich in total dietary fibre and lignin, and the phenolic components analyzed had high antioxidant activity. The extrudates had good functional properties, such as degree of gelatinization, sectional expansion index and water solubility index; the bran was high in bioactive compounds, such as total phenolics. In conclusion, kañiwa may offer an alternative to traditional cereals as a health-promoting food ingredient.


Asunto(s)
Chenopodium/química , Fibras de la Dieta/análisis , Grano Comestible/química , Lignina/análisis , Fenoles/análisis , Grano Comestible/fisiología , Estructuras de las Plantas/química , Semillas/química
14.
Philos Trans R Soc Lond B Biol Sci ; 374(1769): 20180205, 2019 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-30967083

RESUMEN

The cuckoo catfish, Synodontis multipunctatus, is the only known obligate brood parasite among fishes, exploiting the parental care of mouthbrooding cichlids endemic to Lake Tanganyika. Comparisons of this system to brood parasitism in birds may reveal broader principles that underlie the evolution of this life-history strategy in vertebrates. However, little is known about the features of the cuckoo catfish that enable this species to successfully parasitize cichlids. Here, we examine early ontogeny of the cuckoo catfish and compare it to that of its cichlid hosts as well as a non-parasitic congener. We found that cuckoo catfish embryos develop and hatch in advance of host embryos, and begin feeding on cichlid young just as they start to hatch. Overall timing of ontogeny in the cuckoo catfish was found to be similar to that of the substrate-spawning congener Synodontis lucipinnis, suggesting that more rapid development of the cuckoo catfish relative to cichlids is not a unique adaptation to brood parasitism. However, we found that cuckoo catfish progeny exhibit extensive morphological differences from S. lucipinnis, which may represent adaptations to brood parasitism. These life-history observations reveal both similarities and differences between the cuckoo catfish system and brood parasitism in other lineages. This article is part of the theme issue 'The coevolutionary biology of brood parasitism: from mechanism to pattern'.


Asunto(s)
Bagres/fisiología , Cíclidos/parasitología , Interacciones Huésped-Parásitos , Rasgos de la Historia de Vida , Adaptación Biológica , África , Animales , Lagos
15.
Chem Commun (Camb) ; 55(68): 10056-10059, 2019 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-31369024

RESUMEN

Copper dicarboxylate metal-organic framework films are deposited via chemical vapour deposition. Uniform films of CuBDC and CuCDC with an out-of-plane orientation and accessible porosity are obtained from the reaction of Cu and CuO with vaporised dicarboxylic acid linkers.

16.
Nat Commun ; 10(1): 3729, 2019 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-31427584

RESUMEN

The performance of modern chips is strongly related to the multi-layer interconnect structure that interfaces the semiconductor layer with the outside world. The resulting demand to continuously reduce the k-value of the dielectric in these interconnects creates multiple integration challenges and encourages the search for novel materials. Here we report a strategy for the integration of metal-organic frameworks (MOFs) as gap-filling low-k dielectrics in advanced on-chip interconnects. The method relies on the selective conversion of purpose-grown or native metal-oxide films on the metal interconnect lines into MOFs by exposure to organic linker vapor. The proposed strategy is validated for thin films of the zeolitic imidazolate frameworks ZIF-8 and ZIF-67, formed in 2-methylimidazole vapor from ALD ZnO and native CoOx, respectively. Both materials show a Young's modulus and dielectric constant comparable to state-of-the-art porous organosilica dielectrics. Moreover, the fast nucleation and volume expansion accompanying the oxide-to-MOF conversion enable uniform growth and gap-filling of narrow trenches, as demonstrated for 45 nm half-pitch fork-fork capacitors.

17.
Zookeys ; (658): 105-130, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28435388

RESUMEN

Chihuahua is Mexico's largest state, and its physiographic complexity affects the distribution of its herpetofauna. We list amphibians and reptiles for the state of Chihuahua, with their conservation status. We also compare this list to those of six adjoining states in the United States and Mexico (New Mexico, Texas, Coahuila, Durango, Sinaloa, and Sonora). A total of 175 species of amphibians and reptiles is found in Chihuahua. Thirty-eight are amphibians, and 137 reptiles. Chihuahuan amphibians and reptiles represent just over 37% of such species from Chihuahua and neighboring states. Chihuahua shares the highest proportion of its herpetofauna with Sonora and Durango. Most of the herpetofauna of Chihuahua falls in IUCNs least concern category and is not listed by SEMARNAT. However, turtles in Chihuahua are a group of particular conservation concern.

18.
Zookeys ; (594): 123-41, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27408562

RESUMEN

We compiled a check list of the herpetofauna of Nuevo León. We documented 132 species (23 amphibians, 109 reptiles), representing 30 families (11 amphibians, 19 reptiles) and 73 genera (17 amphibians, 56 reptiles). Only two species are endemic to Nuevo León. Nuevo León contains a relatively high richness of lizards in the genus Sceloporus. Overlap in the herpetofauna of Nuevo León and states it borders is fairly extensive. Of 130 native species, 102 are considered species of Least Concern in the IUCN red list, four are listed as Vulnerable, five are listed as Near Threatened, and four are listed as Endangered. According to SEMARNAT, 78 species are not of conservation concern, 25 are subject to Special Protection, 27 are Threatened, and none are listed as in Danger of Extinction. Given current threats to the herpetofauna, additional efforts to understand the ecology and status of populations in Nuevo León are needed.

19.
Biol Open ; 5(8): 1093-101, 2016 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-27402966

RESUMEN

A fundamental question in biology is how an organism's morphology and physiology are shaped by its environment. Here, we evaluate the effects of a hypersaline environment on the morphology and physiology of a population of livebearing fish in the genus Limia (Poeciliidae). We sampled from two populations of Limia perugiae (one freshwater and one hypersaline) in the southwest Dominican Republic. We evaluated relative abundance of osmoregulatory proteins using western blot analyses and used a geometric morphometric approach to evaluate fine-scale changes to size and shape. Our data show that gill tissue isolated from hypersaline fish contained approximately two and a half times higher expression of Na(+)/K(+) ATPase proteins. We also show evidence for mitochondrial changes within the gills, with eight times more complex I and four times higher expression of ATP synthase within the gill tissue from the hypersaline population. The energetic consequences to Limia living in saline and hypersaline environments may be a driver for phenotypic diversity, reducing the overall body size and changing the relative size and shape of the head, as well as impeding the growth of secondary sex features among the males.

20.
Anal Chim Acta ; 732: 145-52, 2012 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-22688046

RESUMEN

The composition and concentration of anthocyanins of grape berry skins were analyzed in order to assess phenotypic variation between four grape wine varieties belonging to 4 different species: Vitis vinifera, Vitis amurensis, Vitis cinerea and Vitis X champinii. High-performance liquid chromatography coupled to mass spectrometry (LC-MS) and NMR spectroscopy (LC-NMR) were used to separate and identify the structure of anthocyanins present in these species. Combination of LC-MS and LC-NMR data resulted in the identification of 33 anthocyanins. In particular, newly reported cis isomers of p-coumaric-derivatives were identified (petunidin-, peonidin- and malvidin-3-(6-p-coumaroyl)-5-diglucoside). In V. cinerea and V. vinifera, anthocyanins were monoglucoside derivatives whereas in V. amurensis and V. X champinii, both mono- and diglucoside derivatives were identified. Malvidin-, delphinidin- and petunidin-derivatives were, respectively, the most abundant components in V. cinerea and V. vinifera, V. amurensis and V. X champinii.


Asunto(s)
Antocianinas/análisis , Cromatografía Líquida de Alta Presión , Espectroscopía de Resonancia Magnética , Espectrometría de Masa por Ionización de Electrospray , Vitis/química , Glucósidos/química
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