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1.
Reg Environ Change ; 23(1): 32, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36741241

RESUMO

The 2018-2019 Central European drought was probably the most extreme in Germany since the early sixteenth century. We assess the multiple consequences of the drought for natural systems, the economy and human health in the German part of the Elbe River basin, an area of 97,175 km2 including the cities of Berlin and Hamburg and contributing about 18% to the German GDP. We employ meteorological, hydrological and socio-economic data to build a comprehensive picture of the drought severity, its multiple effects and cross-sectoral consequences in the basin. Time series of different drought indices illustrate the severity of the 2018-2019 drought and how it progressed from meteorological water deficits via soil water depletion towards low groundwater levels and river runoff, and losses in vegetation productivity. The event resulted in severe production losses in agriculture (minus 20-40% for staple crops) and forestry (especially through forced logging of damaged wood: 25.1 million tons in 2018-2020 compared to only 3.4 million tons in 2015-2017), while other economic sectors remained largely unaffected. However, there is no guarantee that this socio-economic stability will be sustained in future drought events; this is discussed in the light of 2022, another dry year holding the potential for a compound crisis. Given the increased probability for more intense and long-lasting droughts in most parts of Europe, this example of actual cross-sectoral drought impacts will be relevant for drought awareness and preparation planning in other regions. Supplementary Information: The online version contains supplementary material available at 10.1007/s10113-023-02032-3.

2.
J Geophys Res Planets ; 127(9): e2022JE007231, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36583097

RESUMO

We present water vapor vertical distributions on Mars retrieved from 3.5 years of solar occultation measurements by Nadir and Occultation for Mars Discovery onboard the ExoMars Trace Gas Orbiter, which reveal a strong contrast between aphelion and perihelion water climates. In equinox periods, most of water vapor is confined into the low-middle latitudes. In aphelion periods, water vapor sublimated from the northern polar cap is confined into very low altitudes-water vapor mixing ratios observed at the 0-5 km lower boundary of measurement decrease by an order of magnitude at the approximate altitudes of 15 and 30 km for the latitudes higher than 50°N and 30-50°N, respectively. The vertical confinement of water vapor at northern middle latitudes around aphelion is more pronounced in the morning terminators than evening, perhaps controlled by the diurnal cycle of cloud formation. Water vapor is also observed over the low latitude regions in the aphelion southern hemisphere (0-30°S) mostly below 10-20 km, which suggests north-south transport of water still occurs. In perihelion periods, water vapor sublimated from the southern polar cap directly reaches high altitudes (>80 km) over high southern latitudes, suggesting more effective transport by the meridional circulation without condensation. We show that heating during perihelion, sporadic global dust storms, and regional dust storms occurring annually around 330° of solar longitude (L S) are the main events to supply water vapor to the upper atmosphere above 70 km.

3.
Sci Rep ; 12(1): 18328, 2022 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-36316348

RESUMO

In mountain areas, the phenology and productivity of grassland are closely related to snow dynamics. However, the influence that snow melt timing has on grassland growing still needs further attention for a full understanding, particularly at high spatial resolution. Aiming to reduce this knowledge gap, this work exploits 1 m resolution snow depth and Normalized Difference Vegetation Index observations acquired with an Unmanned Aerial Vehicle at a sub-alpine site in the Pyrenees. During two snow seasons (2019-2020 and 2020-2021), 14 NDVI and 17 snow depth distributions were acquired over 48 ha. Despite the snow dynamics being different in the two seasons, the response of grasslands greening to snow melt-out exhibited a very similar pattern in both. The NDVI temporal evolution in areas with distinct melt-out dates reveals that sectors where the melt-out date occurs in late April or early May (optimum melt-out) reach the maximum vegetation productivity. Zones with an earlier or a later melt-out rarely reach peak NDVI values. The results obtained in this study area, suggest that knowledge about snow depth distribution is not needed to understand NDVI grassland dynamics. The analysis did not reveal a clear link between the spatial variability in snow duration and the diversity and richness of grassland communities within the study area.


Assuntos
Pradaria , Neve , Estações do Ano , Temperatura
4.
J Geophys Res Planets ; 127(5): e2021JE007083, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35865508

RESUMO

The Nadir and Occultation for MArs Discovery (NOMAD) instrument suite aboard ExoMars/Trace Gas Orbiter spacecraft is mainly conceived for the study of minor atmospheric species, but it also offers the opportunity to investigate surface composition and aerosols properties. We investigate the information content of the Limb, Nadir, and Occultation (LNO) infrared channel of NOMAD and demonstrate how spectral orders 169, 189, and 190 can be exploited to detect surface CO2 ice. We study the strong CO2 ice absorption band at 2.7 µm and the shallower band at 2.35 µm taking advantage of observations across Martian Years 34 and 35 (March 2018 to February 2020), straddling a global dust storm. We obtain latitudinal-seasonal maps for CO2 ice in both polar regions, in overall agreement with predictions by a general climate model and with the Mars Express/OMEGA spectrometer Martian Years 27 and 28 observations. We find that the narrow 2.35 µm absorption band, spectrally well covered by LNO order 189, offers the most promising potential for the retrieval of CO2 ice microphysical properties. Occurrences of CO2 ice spectra are also detected at low latitudes and we discuss about their interpretation as daytime high altitude CO2 ice clouds as opposed to surface frost. We find that the clouds hypothesis is preferable on the basis of surface temperature, local time and grain size considerations, resulting in the first detection of CO2 ice clouds through the study of this spectral range. Through radiative transfer considerations on these detections we find that the 2.35 µm absorption feature of CO2 ice clouds is possibly sensitive to nm-sized ice grains.

5.
Transl Psychiatry ; 12(1): 146, 2022 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-35393390

RESUMO

Alcohol is part of the usual diet of millions of individuals worldwide. However, not all individuals who drink alcohol experience the same effects, nor will everyone develop an alcohol use disorder. Here we propose that the intestinal microbiota (IMB) helps explain the different consumption patterns of alcohol among individuals. 507 humans participated in this study and alcohol consumption and IMB composition were analyzed. On the other hand, in 80 adult male Wistar rats, behavioral tests, alcohol intoxication, fecal transplantation, administration of antibiotics and collection of fecal samples were performed. For identification and relative quantification of bacterial taxa was used the bacterial 16 S ribosomal RNA gene. In humans, we found that heavy episodic drinking is associated with a specific stool type phenotype (type 1, according to Bristol Stool Scale; p < 0.05) and with an increase in the abundance of Actinobacteria (p < 0.05). Next, using rats, we demonstrate that the transfer of IMB from alcohol-intoxicated animals causes an increase in voluntary alcohol consumption in transplant-recipient animals (p < 0.001). The relative quantification data indicate that the genus Porphyromonas could be associated with the effect on voluntary alcohol consumption. We also show that gut microbiota depletion by antibiotics administration causes a reduction in alcohol consumption (p < 0.001) and altered the relative abundance of relevant phyla such as Firmicutes, Bacteroidetes or Cyanobacteria (p < 0.05), among others. Benjamini-Hochberg false discovery rate (FDR) correction was performed for multiple comparisons. These studies reveal some of the consequences of alcohol on the IMB and provide evidence that manipulation of IMB may alter voluntary alcohol consumption.


Assuntos
Microbioma Gastrointestinal , Consumo de Bebidas Alcoólicas , Animais , Antibacterianos/farmacologia , Bactérias , Transplante de Microbiota Fecal , Masculino , Ratos , Ratos Wistar
6.
Sci Total Environ ; 769: 144702, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33736257

RESUMO

We analyzed the impacts of drought severity on a variety of sectors in a topographically complex basin (the upper Aragón basin 2181 km2) in the Central Spanish Pyrenees. Using diverse data sources including meteorological and hydrological observations, remote sensing and tree rings, we analyze the possible hydrological implications of drought occurrence and severity on water availability in various sectors, including downstream impacts on irrigation water supply for crop production. Results suggest varying responses in forest activity, secondary growth, plant phenology, and crop yield to drought impacts. Specifically, meteorological droughts have distinct impacts downstream, mainly due to water partitioning between streamflow and irrigation channels that transport water to crop producing areas. This implies that drought severity can extend beyond the physical boundaries of the basin, with impacts on crop productivity. This complex response to drought impacts makes it difficult to develop objective basin-scale operational definitions for monitoring drought severity. Moreover, given the high spatial variability in responses to drought across sectors, it is difficult to establish reliable drought thresholds from indices that are relevant across all socio-economic sectors. The anthropogenic impacts (e.g. water regulation projects, ecosystem services, land cover and land use changes) pose further challenges to assessing the response of different systems to drought severity. This study stresses the need to consider the seasonality of drought impacts and appropriate drought time scales to adequately assess and understand their complexity.

7.
Behav Brain Res ; 381: 112441, 2020 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-31863847

RESUMO

Although the genetic influence on global stopping has been extensively investigated, little is known about the genetic contribution to other more complex forms of inhibitory control such as selective stopping. The selectivity of inhibitory control can be assessed by using the stimulus-selective stop-signal task. Notably, recent behavioural and neural evidence indicates that individuals can adopt selective but also non-selective stopping strategies to solve it. This study aimed to investigate for the first time the influence of two relevant dopaminergic polymorphisms (in COMT and DRD2 genes) on stimulus-selective stopping in a sample of 529 adults. Results showed that although none of these polymorphisms (neither individually nor in combination) modulate the latency of the stop process in each strategy (the stop-signal reaction time), the choice of strategy was influenced by their interaction. These results suggest that dopaminergic polymorphisms might influence strategy adoption in selective stopping paradigms, which constitutes a novel finding.


Assuntos
Catecol O-Metiltransferase/genética , Inibição Psicológica , Receptores de Dopamina D2/genética , Adolescente , Feminino , Genética Comportamental , Humanos , Masculino , Polimorfismo de Nucleotídeo Único , Tempo de Reação/genética , Adulto Jovem
8.
Psychopharmacology (Berl) ; 236(4): 1187-1197, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30470859

RESUMO

RATIONALE: Only in Europe it can be estimated that more than 20 million of people would be affected by hypothyroidism in some moment of their life. Given that ethanol consumption is so frequent, it would be reasonable to ask what the consequences of ethanol consumption in those individuals affected by hypothyroidism are. OBJECTIVES: To study the interaction between hypothyroidism and ethanol consumption. METHODS: We study ethanol consumption in a rat model of methyl-mercaptoimidazole-induced-adult-onset hypothyroidism and thyroid T4/T3 hormone supplementation. Also, we studied the effects of ethanol on motor activity, memory, and anxiety. RESULTS: We found that hypothyroidism increased the voluntary ethanol consumption and that this was enhanced by thyroid hormone supplementation. Hypothyroidism was associated with motor hyperactivity which was prevented either by T4/T3 supplementation or ethanol. The relationship between hypothyroidism, ethanol, and anxiety was more complex. In an anxiogenic context, hypothyroidism and T4/T3 supplementation would increase immobility, an anxiety-like behavior, while in a less anxiogenic context would decrease rearing, a behavior related to anxiety. Regarding memory, acute ethanol administration did not alter episodic-like memory in hypothyroid rats. Gene expression of enzymes involved in the metabolism of ethanol, i.e., Adh1 and Aldh2, were altered by hypothyroidism and T4/T3 supplementation. CONCLUSIONS: Our results suggest that hypothyroid patients would need personalized attention in terms of ethanol consumption. In addition, they point that it would be useful to embrace the thyroid axis in the study of ethanol addiction, including as a possible therapeutic target for the treatment of alcoholism and its comorbid disorders.


Assuntos
Consumo de Bebidas Alcoólicas/sangue , Etanol/administração & dosagem , Hipotireoidismo/sangue , Fatores Etários , Consumo de Bebidas Alcoólicas/efeitos adversos , Consumo de Bebidas Alcoólicas/psicologia , Aldeído-Desidrogenase Mitocondrial/sangue , Animais , Ansiedade/sangue , Ansiedade/psicologia , Humanos , Hipotireoidismo/complicações , Hipotireoidismo/psicologia , Masculino , Ratos , Ratos Wistar , Hormônios Tireóideos/sangue , Tiroxina/sangue , Tri-Iodotironina/sangue
9.
Science ; 355(6332): 1392-1395, 2017 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-28325842

RESUMO

The Rosetta spacecraft spent ~2 years orbiting comet 67P/Churyumov-Gerasimenko, most of it at distances that allowed surface characterization and monitoring at submeter scales. From December 2014 to June 2016, numerous localized changes were observed, which we attribute to cometary-specific weathering, erosion, and transient events driven by exposure to sunlight and other processes. While the localized changes suggest compositional or physical heterogeneity, their scale has not resulted in substantial alterations to the comet's landscape. This suggests that most of the major landforms were created early in the comet's current orbital configuration. They may even date from earlier if the comet had a larger volatile inventory, particularly of CO or CO2 ices, or contained amorphous ice, which could have triggered activity at greater distances from the Sun.

10.
Eur J Nutr ; 56(4): 1621-1628, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27029919

RESUMO

PURPOSE: Obesity increases the risk of cardiovascular disease, type 2 diabetes mellitus and cancer development. Autophagy and apoptosis are critical processes for development and homeostasis in multicellular organisms and have been linked to a variety of disorders. We aimed to investigate whether the quantity and quality of dietary fat can influence these processes in the adipose tissue of obese people. METHODS: A randomized, controlled trial within the LIPGENE study assigned 39 obese people with metabolic syndrome to 1 of 4 diets: (a) a high-saturated fatty acid diet, (b) a high-monounsaturated fatty acid (HMUFA) diet, and (c, d) two low-fat, high-complex carbohydrate diets supplemented with long-chain n-3 polyunsaturated fatty acids (LFHCC n-3) or placebo (LFHCC), for 12 weeks each. RESULTS: We found an increase in the expression of autophagy-related BECN1 and ATG7 genes after the long-term consumption of the HMUFA diet (p = 0.001 and p = 0.004, respectively) and an increase in the expression of the apoptosis-related CASP3 gene after the long-term consumption of the LFHCC and LFHCC n-3 diets (p = 0.001 and p = 0.029, respectively). CASP3 and CASP7 gene expression changes correlated with HOMA index. CONCLUSION: Our results suggest that the processes of autophagy and apoptosis in adipose tissue may be modified by diet and that the consumption of a diet rich in monounsaturated fat may contribute to adipose tissue homeostasis by increasing autophagy. They also reinforce the notion that apoptosis in adipose tissue is linked to insulin resistance. CLINICAL TRIAL REGISTRATION NUMBER: ClinicalTrials.gov NCT00429195.


Assuntos
Adipócitos/citologia , Tecido Adiposo/fisiopatologia , Apoptose , Autofagia , Gorduras na Dieta/administração & dosagem , Adulto , Idoso , Proteína 7 Relacionada à Autofagia/genética , Proteína 7 Relacionada à Autofagia/metabolismo , Proteína Beclina-1/genética , Proteína Beclina-1/metabolismo , Glicemia/metabolismo , Caspase 3/genética , Caspase 3/metabolismo , Caspase 7/genética , Caspase 7/metabolismo , Dieta com Restrição de Gorduras , Dieta Hiperlipídica , Ácidos Graxos/administração & dosagem , Ácidos Graxos Monoinsaturados/administração & dosagem , Ácidos Graxos Ômega-3/administração & dosagem , Feminino , Regulação da Expressão Gênica , Homeostase , Humanos , Resistência à Insulina , Masculino , Síndrome Metabólica/fisiopatologia , Pessoa de Meia-Idade , Obesidade/fisiopatologia , Método Simples-Cego
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