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1.
Front Plant Sci ; 15: 1332840, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38545390

RESUMO

Potato (Solanum tuberosum L.) is considered one of the most widely consumed crops worldwide, due to its high yield and nutritional profile, climate change-related environmental threats and increasing food demand. This scenario highlights the need of sustainable agricultural practices to enhance potato productivity, while preserving and maintaining soil health. Plant growth-promoting bacteria (PGPB) stimulate crop production through biofertilization mechanisms with low environmental impact. For instance, PGPB promote biological nitrogen fixation, phosphate solubilization, production of phytohormones, and biocontrol processes. Hence, these microbes provide a promising solution for more productive and sustainable agriculture. In this study, the effects of Bacillus amyloliquefaciens QST713 based-product (MINUET™, Bayer) were assessed in terms of yield, soil microbiome, potato peel and petiole nutrient profile as a promising PGPB in a wide range of potato cultivars across the United States of America. Depending on the location, potato yield and boron petiole content increased after biostimulant inoculation to maximum of 24% and 14%, respectively. Similarly, nutrient profile in potato peel was greatly improved depending on the location with a maximum of 73%, 62% and 36% for manganese, zinc and phosphorus. Notably, fungal composition was shifted in the treated group. Yield showed strong associations with specific microbial taxa, such as Pseudoarthrobacter, Ammoniphilus, Ideonella, Candidatus Berkiella, Dongia. Moreover, local networks strongly associated with yield, highlighting the important role of the native soil microbiome structure in indirectly maintaining soil health. Our results showed that treatment with B. amyloliquefaciens based product correlated with enhanced yield, with minor impacts on the soil microbiome diversity. Further studies are suggested to disentangle the underlying mechanisms of identified patterns and associations.

2.
Opt Express ; 31(23): 37653-37662, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-38017891

RESUMO

A transmissive adaptable optical setup to generate a range of perfect vortex beams (PVBs) carrying different topological charges (TC) without using moving parts is presented. The setup is composed of an ad hoc transparent reconfigurable liquid crystal (LC) spiral phase plate (SPP), a refractive axicon and a convergent refractive lens. The LC SPP electrodes are manufactured ablating indium-tin oxide (ITO) glass substrates using direct laser writing (DLW) resulting in a very high fill factor device. In-house tailored electronics drive the 72 LC SPP electrodes giving rise to 72 different configurations with orbital angular momentum. In this work, the generation of PVBs with 36 positive or 36 negative TCs using this optical setup is accomplished.

3.
Proc Natl Acad Sci U S A ; 120(40): e2304032120, 2023 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-37748063

RESUMO

Fairy circles (FCs) are regular vegetation patterns found in drylands of Namibia and Western Australia. It is virtually unknown whether they are also present in other regions of the world and which environmental factors determine their distribution. We conducted a global systematic survey and found FC-like vegetation patterns in 263 sites from 15 countries and three continents, including the Sahel, Madagascar, and Middle-West Asia. FC-like vegetation patterns are found in environments characterized by a unique combination of soil (including low nutrient levels and high sand content) and climatic (arid regions with high temperatures and high precipitation seasonality) conditions. In addition to these factors, the presence of specific biological elements (termite nests) in certain regions also plays a role in the presence of these patterns. Furthermore, areas with FC-like vegetation patterns also showed more stable temporal productivity patterns than those of surrounding areas. Our study presents a global atlas of FCs and provides unique insights into the ecology and biogeography of these fascinating vegetation patterns.


Assuntos
Clima Desértico , Ecologia , Geografia , Plantas , Animais
4.
Emergencias ; 34(4): 259-267, 2022 08.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-35833764

RESUMO

OBJECTIVES: To examine gender-related differences in the management and survival of out-of-hospital cardiac arrest (OHCA) in Spain during 2 time series. MATERIAL AND METHODS: Analysis of data recorded in the prospective Spanish OHCA registry (OHSCAR in its Spanish acronym) for 2 time series (2013-2014 and 2017-2018). We included all 11 036 consecutive cases in which an emergency team intervened. The dependent variables were arrival at the hospital after return of spontaneous circulation, overall survival to discharge, and overall survival with good neurological outcomes. Sex was the independent variable. We report descriptive statistics, patient group comparisons, and changes over time. RESULTS: Women were significantly older and less likely to experience an OHCA in a public place, receive automatic external defibrillation, have a shockable heart rhythm, and be attended by an ambulance team within 15 minutes. In addition, fewer women underwent percutaneous coronary interventions or received treatment for hypothermia on admission to the hospital. In 2013-2014 and 2017-2018, respectively, the likelihood of survival was lower for women than men on admission (odds ratio [OR], 0.52 vs OR, 0.61; P .001 and P = .009 in the 2 time series) and at discharge (OR, 0.69 vs 0.72 for men; P = .001 in both time series). Survival with good neurological outcomes was also less likely in women (OR, 0.50 vs 0.63; P .001 in both series). CONCLUSION: The odds for survival and survival with good neurological outcomes were lower for women in nearly all patient groups in both time series. These findings suggest the need to adopt new approaches to address gender differences in OHCA.


OBJETIVO: Examinar las diferencias de género en las características de la parada cardiaca extrahospitalaria (PCRE), los tratamientos, la supervivencia, y los cambios evolutivos en España. METODO: Datos de dos series temporales (2013/2014 y 2017/2018) del registro prospectivo de PCRE (OHSCAR). Se incluyeron todos los casos consecutivos en los que intervino un equipo de emergencias. Las variables dependientes fueron las variables de atención de la PCRE, la llegada al hospital con pulso espontáneo, la supervivencia global al alta, y con buenos resultados neurológicos. El sexo fue la variable independiente. RESULTADOS: Las mujeres fueron significativamente mayores, menos propensas a presentar una PCRE en lugar público, recibir desfibrilación externa automática, tener un ritmo inicial desfibrilable y ser atendidas por una ambulancia en menos de 15 minutos. Además, menos mujeres recibieron intervención coronaria percutánea o hipotermia al ingreso hospitalario. Tanto en 2013/2014 como en 2017/2018 las mujeres tuvieron menos probabilidades de supervivencia al ingreso hospitalario (OR = 0,52; p 0,001; OR = 0,61; p = 0,009 respectivamente), y al alta hospitalaria (OR = 0,69; p = 0,001; OR = 0,72; p = 0,001, respectivamente) y con buenos resultados neurológicos (OR = 0,50; p 0,001; OR = 0,63; p 0,001, respectivamente). CONCLUSIONES: En ambos periodos las mujeres tuvieron menos probabilidades de sobrevivir y de hacerlo en buenas condiciones neurológicas. Estos resultados indican la necesidad de adoptar nuevos enfoques para abordar las diferencias de género en la PCRE.


Assuntos
Reanimação Cardiopulmonar , Serviços Médicos de Emergência , Parada Cardíaca Extra-Hospitalar , Feminino , Humanos , Masculino , Parada Cardíaca Extra-Hospitalar/terapia , Estudos Prospectivos , Fatores Sexuais , Espanha/epidemiologia
5.
Sci Data ; 9(1): 14, 2022 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-35058464

RESUMO

Drylands cover ~41% of the terrestrial surface. In these water-limited ecosystems, soil moisture contributes to multiple hydrological processes and is a crucial determinant of the activity and performance of above- and belowground organisms and of the ecosystem processes that rely on them. Thus, an accurate characterisation of the temporal dynamics of soil moisture is critical to improve our understanding of how dryland ecosystems function and are responding to ongoing climate change. Furthermore, it may help improve climatic forecasts and drought monitoring. Here we present the MOISCRUST dataset, a long-term (2006-2020) soil moisture dataset at a sub-daily resolution from five different microsites (vascular plants and biocrusts) in a Mediterranean semiarid dryland located in Central Spain. MOISCRUST is a unique dataset for improving our understanding on how both vascular plants and biocrusts determine soil water dynamics in drylands, and thus to better assess their hydrological impacts and responses to ongoing climate change.

6.
Front Chem ; 9: 733881, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34422775

RESUMO

The catalytic reduction of nitrites over Pt-In catalysts supported on activated carbon has been studied in a semi-batch reactor, at room temperature and atmospheric pressure, and using hydrogen as the reducing agent. The influence of the indium content on the activity and selectivity was evaluated. Monometallic Pt catalysts are very active for nitrite reduction, but the addition of up to 1 wt% of indium significantly increases the nitrogen selectivity from 0 to 96%. The decrease in the accessible noble metal surface area reduces the amount of hydrogen available at the catalyst surface, this favoring the combination of nitrogen-containing intermediate molecules to promote the formation of N2 instead of being deeply hydrogenated into NH4+. Several activated carbon-supported Pt-In catalysts, activated under different calcination and reduction temperatures, have been also evaluated in nitrite reduction. The catalyst calcined and reduced at 400°C showed the best performance considering both the activity and the selectivity to nitrogen. This enhanced selectivity is ascribed to the formation of Pt-In alloy. The electronic properties of Pt change upon alloy formation, as it is demonstrated by XPS.

7.
New Phytol ; 231(2): 540-558, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33864276

RESUMO

Despite their extent and socio-ecological importance, a comprehensive biogeographical synthesis of drylands is lacking. Here we synthesize the biogeography of key organisms (vascular and nonvascular vegetation and soil microorganisms), attributes (functional traits, spatial patterns, plant-plant and plant-soil interactions) and processes (productivity and land cover) across global drylands. These areas have a long evolutionary history, are centers of diversification for many plant lineages and include important plant diversity hotspots. This diversity captures a strikingly high portion of the variation in leaf functional diversity observed globally. Part of this functional diversity is associated with the large variation in response and effect traits in the shrubs encroaching dryland grasslands. Aridity and its interplay with the traits of interacting plant species largely shape biogeographical patterns in plant-plant and plant-soil interactions, and in plant spatial patterns. Aridity also drives the composition of biocrust communities and vegetation productivity, which shows large geographical variation. We finish our review by discussing major research gaps, which include: studying regular vegetation spatial patterns; establishing large-scale plant and biocrust field surveys assessing individual-level trait measurements; knowing whether the impacts of plant-plant and plant-soil interactions on biodiversity are predictable; and assessing how elevated CO2 modulates future aridity conditions and plant productivity.


Assuntos
Biodiversidade , Ecossistema , Geografia , Plantas , Solo
8.
Med Eng Phys ; 90: 23-32, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33781477

RESUMO

This work presents an identification procedure of flexural behavior of toenail plates in twenty subjects with no history of feet or nail injury as of in-vivo measurements. In particular, four different mechanical models are considered to describe such properties, ranging from the pure elastic to viscoelastic behavior, the latter from the classical and fractional points of view. The quality of the adjustment of each model is examined by a group of performance indices. Experimental data show that the best identification is achieved by the fractional order viscoelastic model for all subjects. These novel results in modeling flexural behavior of toenails are consistent with the published literature suggesting that viscoelastic materials may be successfully modeled with derivatives of fractional order. This could contribute, together with additional variables, to help health professionals, and more especially podiatrists, to have reliable and quantitative measures of the nail flexural behavior which can be susceptible of treatment or for prevention.


Assuntos
Unhas , Humanos
9.
Ecol Modell ; 436: 109288, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32982015

RESUMO

In this letter we present comments on the article "A global-scale ecological niche model to predict SARS-CoV-2 coronavirus" by Coro published in 2020.

11.
Proc Natl Acad Sci U S A ; 117(22): 12192-12200, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32393624

RESUMO

Late-spring frosts (LSFs) affect the performance of plants and animals across the world's temperate and boreal zones, but despite their ecological and economic impact on agriculture and forestry, the geographic distribution and evolutionary impact of these frost events are poorly understood. Here, we analyze LSFs between 1959 and 2017 and the resistance strategies of Northern Hemisphere woody species to infer trees' adaptations for minimizing frost damage to their leaves and to forecast forest vulnerability under the ongoing changes in frost frequencies. Trait values on leaf-out and leaf-freezing resistance come from up to 1,500 temperate and boreal woody species cultivated in common gardens. We find that areas in which LSFs are common, such as eastern North America, harbor tree species with cautious (late-leafing) leaf-out strategies. Areas in which LSFs used to be unlikely, such as broad-leaved forests and shrublands in Europe and Asia, instead harbor opportunistic tree species (quickly reacting to warming air temperatures). LSFs in the latter regions are currently increasing, and given species' innate resistance strategies, we estimate that ∼35% of the European and ∼26% of the Asian temperate forest area, but only ∼10% of the North American, will experience increasing late-frost damage in the future. Our findings reveal region-specific changes in the spring-frost risk that can inform decision-making in land management, forestry, agriculture, and insurance policy.


Assuntos
Mudança Climática , Temperatura Baixa , Folhas de Planta/crescimento & desenvolvimento , Estações do Ano , Árvores/crescimento & desenvolvimento , Ásia , Europa (Continente) , Florestas , América do Norte , Fenótipo , Análise Espaço-Temporal , Temperatura
13.
Biol Lett ; 15(7): 20190357, 2019 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-31337290

RESUMO

Fire is the most frequent disturbance in the Ericaceous Belt (ca 3000-4300 m.a.s.l.), one of the most important plant communities of tropical African mountains. Through resprouting after fire, Erica establishes a positive fire feedback under certain burning regimes. However, present-day human activity in the Bale Mountains of Ethiopia includes fire and grazing systems that may have a negative impact on the resilience of the ericaceous ecosystem. Current knowledge of Erica-fire relationships is based on studies of modern vegetation, lacking a longer time perspective that can shed light on baseline conditions for the fire feedback. We hypothesize that fire has influenced Erica communities in the Bale Mountains at millennial time-scales. To test this, we (1) identify the fire history of the Bale Mountains through a pollen and charcoal record from Garba Guracha, a lake at 3950 m.a.s.l., and (2) describe the long-term bidirectional feedback between wildfire and Erica, which may control the ecosystem's resilience. Our results support fire occurrence in the area since ca 14 000 years ago, with particularly intense burning during the early Holocene, 10.8-6.0 cal ka BP. We show that a positive feedback between Erica abundance and fire occurrence was in operation throughout the Lateglacial and Holocene, and interpret the Ericaceous Belt of the Ethiopian mountains as a long-term fire resilient ecosystem. We propose that controlled burning should be an integral part of landscape management in the Bale Mountains National Park.


Assuntos
Ecossistema , Incêndios , Carvão Vegetal , Etiópia , Humanos , Lagos
14.
Langmuir ; 35(18): 6089-6105, 2019 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-30990709

RESUMO

Materials able to produce the reduction of nitrate from water without the need of a metal catalyst and with avoiding the use of gaseous hydrogen have been developed by combining the synergistic properties of titania and two conducting polymers. Polymerization of aniline and pyrrol on titanium dioxide in the presence of two different oxidants/dopants (iron trichloride or potassium persulfate) has been evaluated. The resulting hybrid materials have good thermal stability imparted by the titania counterpart, and a considerable conductivity provided by the conducting polymers. The capability of the hybrid materials of reducing aqueous nitrate has been assessed and compared to the catalytic hydrogenation of nitrate using a platinum catalyst supported on these hybrid synthesized materials. The mechanism of nitrate abatement implies adsorption of nitrate on the polymer by ion exchange with the dopant anion, followed by the reduction of nitrate. The electron transfer from titania to the conducting polymer in the hybrid material favors the reductive ability of the polymer, in such a way that nitrate is selectively reduced with a very low production of undesirable side products. The obtained results show that the activity and selectivity of the catalytic reduction of nitrate with dihydrogen in the presence of a platinum catalyst supported on the hybrid materials are considerably lower than those of the metal-free nanocomposites.

15.
ISA Trans ; 89: 139-157, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30772063

RESUMO

The control of robots that interact with the environment is an open area of research. Two applications that benefit from this study are: the control of the force exerted by a robot on an object, which allows the robot to perform complex tasks like assembly operations, and the control of collisions, which allows the robot safely collaborate with humans. Robot control is difficult in these cases because: (1) bouncing between free and constrained motion appears that may cause instability, (2) switching between free motion (position) controller and constrained motion (force) controller is required being the switching instants difficult to know and (3) robot control must be robust since the mechanical impedance of the environment is unknown. Robots with flexible links may alleviate these drawbacks. Previous research on flexible robots proved stability of a PD controller that fed back the motor position when contacting an unknown environment, but force control was not achieved. This paper proposes a control system that combines a fractional-order D tip position controller with a feedforward force control. It attains higher stability robustness and higher phase margin than a PD controller, which is the integer-order controller of similar complexity. This controller outperforms previous controllers: (1) it achieves force control with nearly zero steady state error, (2) this control is robust to uncertainties in the environment and motor friction, (3) it guarantees stability (like others) but it also guarantees a higher value of the phase margin, i.e., a higher damping, and a more efficient vibration cancellation, and (4) it effectively removes bouncing. Experimental results prove the effectiveness of this new controller.

17.
Ecol Evol ; 8(13): 6671-6681, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30038766

RESUMO

Studying demographic history of species provides insight into how the past has shaped the current levels of overall biodiversity and genetic composition of species, but also how these species may react to future perturbations. Here we investigated the demographic history of the willow grouse (Lagopus lagopus), rock ptarmigan (Lagopus muta), and black grouse (Tetrao tetrix) through the Late Pleistocene using two complementary methods and whole genome data. Species distribution modeling (SDM) allowed us to estimate the total range size during the Last Interglacial (LIG) and Last Glacial Maximum (LGM) as well as to indicate potential population subdivisions. Pairwise Sequentially Markovian Coalescent (PSMC) allowed us to assess fluctuations in effective population size across the same period. Additionally, we used SDM to forecast the effect of future climate change on the three species over the next 50 years. We found that SDM predicts the largest range size for the cold-adapted willow grouse and rock ptarmigan during the LGM. PSMC captured intraspecific population dynamics within the last glacial period, such that the willow grouse and rock ptarmigan showed multiple bottlenecks signifying recolonization events following the termination of the LGM. We also see signals of population subdivision during the last glacial period in the black grouse, but more data are needed to strengthen this hypothesis. All three species are likely to experience range contractions under future warming, with the strongest effect on willow grouse and rock ptarmigan due to their limited potential for northward expansion. Overall, by combining these two modeling approaches, we have provided a multifaceted examination of the biogeography of these species and how they have responded to climate change in the past. These results help us understand how cold-adapted species may respond to future climate changes.

18.
Dalton Trans ; 47(8): 2610-2618, 2018 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-29392258

RESUMO

A member of the family of compounds with the formula Na3V2O2x(PO4)2F3-2x is synthesized by carbothermal reduction and 2 consecutive hydrothermal processes. The initial structural and spectroscopic characterization indicates that there are two phases in the as-synthesized material, a mixed valent phase with an intermediate V oxidation state adopting a P42/mnm space group at about 66%, and another phase with a V oxidation state close to V3+ adopting an Amam space group at about 33%. The role of each species in the electrode function is interrogated using in situ synchrotron X-ray diffraction and these data indicate that soon after charge begins, the Amam phase transforms into the P42/mnm phase. Further structural evolution of the material shows a prevailing two-phase reaction at lower potentials and a significant solid solution region during the high potential feature in the electrochemical curve with a final two-phase region at the end of charge. The conversion of the Amam component into P42/mnm showed no reversibility upon discharge. This phase-mixed electrode appears to illustrate that the mixed valent P42/mnm phase dominates electrochemical behavior during cycling and this may prove vital when preparing members in the sodium vanadium fluorophosphate family, especially if there is an energetically preferred phase for cycling.

19.
ChemCatChem ; 9(22): 4159-4163, 2017 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-29242719

RESUMO

We report a facile and general approach for preparing ultrafine ruthenium nanocatalysts by using a plasma-assisted synthesis at <100 °C. The resulting Ru nanoparticles are monodispersed (typical size 2 nm) and remain that way upon loading onto carbon and TiO2 supports. This gives robust catalysts with excellent activities in both organosilane oxidation and the oxygen evolution reaction.

20.
J Colloid Interface Sci ; 494: 98-106, 2017 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-28152440

RESUMO

Three different conducting polymers, polythiophene (PT), polypirrol (PPY) and polyaniline (PANI) have been synthesized via oxidative chemical polymerization in aqueous media, in such a way that the synthesis protocol did not involve any toxic solvents. They have been tested in the abatement of nitrates from an aqueous solution without the need of any metal catalyst. The N-containing polymers (PANI and PPy) were able to remove nitrates to a level that accomplishes the European legislation requirements; however, the nature of each polymer greatly influenced the process mechanism. Whereas ion exchange between Cl- and SO42- counter-ions in the polymer and NO3- from water is the main responsible for the effective nitrate removal in PANI, as assessed by FTIR and XPS analyses, the nitrate removal mechanism on PPy is based in an electron transfer from the polymer to nitrate through N sites located in the pyrrolic ring. On the other hand, PT was not able to exchange nitrate unless it was synthesized with FeCl3 as oxidant/dopant and an anionic surfactant (sodium dodecyl sulfate -SDS-) is used. In that case, the electrostatic attraction between sulfate (OSO3-) groups from the surfactant and Fe3+ ions from FeCl3 produced the anchoring of Cl- to the oxidized PT growing chain, this favoring ion exchange with nitrate in the aqueous solution, followed by a redox process.

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