A New Study of Sea Spray Optical Properties from Multi-Sensor Spaceborne Observations

Retrievals of aerosol optical depth (AOD) from the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) satellite sensor require the assumption of an extinction-to-backscatter ratio, also known as the lidar ratio. This paper evaluates a new method to calculate lidar ratio of sea spray aerosol using two independent sources: the AOD from Synergized Optical Depth of Aerosols (SODA) and the integrated attenuated backscatter from CALIOP. The method applied in this study allows particulate lidar ratio to be calculated for individual CALIOP retrievals of single aerosol layer columns over the ocean. Analyses are carried out using CALIOP level 2, 5km sea spray aerosol layer products and collocated SODA nighttime data from December 2007 to December 2009. The global mean lidar ratio for sea spray aerosols was found to be 26 sr, roughly 30 higher than the one prescribed by CALIOP. Data analysis also showed considerable spatiotemporal variability in calculated lidar ratio over different parts of the remote oceans. The calculated aerosol lidar ratios are shown to be inversely related to the mean ocean surface wind speed: increase in ocean surface wind speed (U10) from 0 to 15 ms-1 reduces the mean lidar ratios for sea spray particles from 32 sr (for 0 U10 4 ms-1) to 22 sr (for U10 15 ms-1). Such changes in the lidar ratio are expected to have a corresponding effect on sea spray AOD. The outcomes of this study are relevant for future improvements of the SODA and CALIOP operational product and could lead to more accurate retrievals of sea spray AOD

Population systems of Eurasian water frogs (Pelophylax) in the south of Ukraine

Ecological and evolutionary consequences of population-genetic processes that occur because of natural cross-species hybridization can show mechanisms of overcoming the reproductive barrier and obtaining the species status by a hybrid taxon. This is clearly seen in the population systems of Eurasian water frogs – Pelophylax esculentus complex. The P. esculentus (E) hybrid usually discards one of the parental genomes of P. lessonae (L) or P. ridibundus (R) and reproduces semi-clonally. The genetic structure and direction of gene flows precisely depend on the type and distribution of mixed or pure population systems of water frogs. Three population systems in the south of Ukraine were identified and confirmed as RR, RE and REL. The populations of P. ridibundus are most common (76.2%). A mixed population systems of P. ridibundus and P. esculentus (20.0%) are concentrated in the floodplains of large rivers where triploids were found and the unisexual hybrids (1.0♂ : 0.1♀) were proved. Parent species populations having different ploidy of P. esculentus such as 3n and for the first time 4n were found. A mixed system of three taxa (REL) is rare (3.8%) and locally concentrated in the lower Danube and Dnieper with the smallest proportion of P. lessonae. We did not find populations of P. lessonae (LL), P. esculentus (EE, very rare system of hybrids only), and two mixed populations of parental species RL and semi-clonal LE in the south of Ukraine, but they are known for northern areas. The high number of P. ridibundus tends to decrease; the scarce P. esculentus and the extremely rare P. lessonae require special conservation measures. P. ridibundus (RR) occupies a wide range of diverse natural, permanent, temporary, coastal, continental, and artificial freshwater bodies, including synanthropic ecosystems. Mixed population systems inhabit willow and poplar forests in the floodplains of large rivers. In the south of Ukraine rare and isolated populations of the water frogs occurring outside the main range can be relict. Biotopic preferences, ratio and number of constituent taxa are crucial for an adequate assessment of biological (taxonomic) diversity and development of an appropriate strategy for the population systems’ conservation. Such characteristics as unisexuality of hybrids, their spreading patterns, specific sex structure and ploidy in different population systems of the P. esculentus complex contribute to the understanding of the hybridogenetic dynamics; produce new tendencies of becoming independent hybridogenous taxa and emergence of new evolutionary relationships

Local industrial pollution induces astrocyte cytoskeleton rearrangement in the dice snake brain: GFAP as a biomarker

The present study was designed to evaluate the responsiveness of modulation of glial fibrillary acidic protein (GFAP) content and its fragmentation in the snake brain as a biomarker of local industrial pollution of aquatic ecosystems. Despite GFAP being a well known cytoskeleton marker of astrocytes’ reactivity in the brain of vertebrates, its expression in the snake brain remains insufficiently described. The GFAP expression and its fragmentation were detected using the immunoblot method in the snake brain. ROS level was determined with dichlorofluorescein diacetate fluorescence. The content of the glial fibrillary acidic protein (GFAP) of filament (cytoskeleton) and soluble (cytosol) fractions in the brain of dice snake Natrix tessellata from three ecosystems with different rates of industrial pollution were studied (two polluted and one clean control site). Characteristic increase in GFAP fragmentation was noted for the snakes from both the researched polluted sites. Significant increase in the content of the GFAP cleaved polypeptide fragments induced by industrial pollution exposure was confirmed in the snakes’ brains. Meaningful GFAP fragmentation was determined in snake brain astrocytes as an increase in cleaved fragments of 47–35 kDa molecular weight for both soluble and cytoskeletal GFAP fractions. We found significant abnormality in the ratio of the GFAP soluble fraction to the cytoskeletal one in contaminant-exposed dice snakes. It should testify to significant metabolic disturbance in nerve cells of the dice snakes. Furthermore, growth of reactive oxygen species level as the main cause of oxidative stress was determined in brains of the snakes exposed to environmental toxicity. Thus, astrocyte cytoskeleton disorders are associated with pollutant-induced redox imbalance in the snake brain. Despite the limited data on glial cell biology in the reptilian brain, the observed results prove that snake astrocytes can respond to the environmental toxicity using typical astroglial response. The presented results evidence that monitoring of molecular characteristics of glial cytoskeleton in dice snakes could be used as reliable biomarker of neurotoxicity and adverse effects of industrial pollution. Further studies are required to elucidate the role of astrocyte cytoskeleton in the response against neurotoxic contaminants

Matrix Metalloproteinase Gene Delivery for Liver Fibrosis

The resolution of advanced liver fibrosis has been recently recognized to be possible, if the causative stimuli are successfully removed. However, whether complete resolution from cirrhosis, the end stage of liver fibrosis, can be achieved is still questionable. Delivery of interstitial collagenases, such as matrix metalloproteinase (MMP)-1, in the liver could be an attractive strategy to treat advanced hepatic fibrosis from the view point that the imbalance between too few interstitial collagenases and too many of their inhibitors is the main obstacle to the resolution from fibrosis. Remodeling of hepatic extracellular matrix by delivered interstitial collagenases also facilitates the disappearance of activated hepatic stellate cells, the main matrix-producing cells in the liver, and promotes the proliferation of hepatocytes. This review will focus on the impact of the gene delivery of MMPs for the treatment of advanced liver fibrosis while discussing other current therapeutic strategies for liver fibrosis, and on the need for the development of a safe and effective delivery system of MMPs

Leaf litter traits of invasive alien species slow down decomposition compared to Spanish natives: a broad phylogenetic comparison.

Leaf traits related to the performance of invasive alien species can influence nutrient cycling through litter decomposition. However, there is no consensus yet about whether there are consistent differences in functional leaf traits between invasive and native species that also manifest themselves through their "after life" effects on litter decomposition. When addressing this question it is important to avoid confounding effects of other plant traits related to early phylogenetic divergences and to understand the mechanism underlying the observed results to predict which invasive species will exert larger effects on nutrient cycling. We compared initial leaf litter traits, and their effect on decomposability as tested in standardized incubations, in 19 invasive-native pairs of co-familial species from Spain. They included 12 woody and seven herbaceous alien species representative of the Spanish invasive flora. The predictive power of leaf litter decomposition rates followed the order: growth form > family > status (invasive vs. native) > leaf type. Within species pairs litter decomposition tended to be slower and more dependent on N and P in invaders than in natives. This difference was likely driven by the higher lignin content of invader leaves. Although our study has the limitation of not representing the natural conditions from each invaded community, it suggests a potential slowing down of the nutrient cycle at ecosystem scale upon invasion. © Springer-Verlag 2009

Apoptotic markers in cultured fibroblasts correlate with brain metabolites and regional brain volume in antipsychotic-naive first-episode schizophrenia and healthy controls

Contains fulltext : 152783.pdf (publisher's version ) (Open Access)Cultured fibroblasts from first-episode schizophrenia patients (FES) have shown increased susceptibility to apoptosis, which may be related to glutamate dysfunction and progressive neuroanatomical changes. Here we determine whether apoptotic markers obtained from cultured fibroblasts in FES and controls correlate with changes in brain glutamate and N-acetylaspartate (NAA) and regional brain volumes. Eleven antipsychotic-naive FES and seven age- and gender-matched controls underwent 3-Tesla magnetic resonance imaging scanning. Glutamate plus glutamine (Glx) and NAA levels were measured in the anterior cingulate (AC) and the left thalamus (LT). Hallmarks of apoptotic susceptibility (caspase-3-baseline activity, phosphatidylserine externalization and chromatin condensation) were measured in fibroblast cultures obtained from skin biopsies after inducing apoptosis with staurosporine (STS) at doses of 0.25 and 0.5 muM. Apoptotic biomarkers were correlated to brain metabolites and regional brain volume. FES and controls showed a negative correlation in the AC between Glx levels and percentages of cells with condensed chromatin (CC) after both apoptosis inductions (STS 0.5 muM: r = -0.90; P = 0.001; STS 0.25 muM: r = -0.73; P = 0.003), and between NAA and cells with CC (STS 0.5 muM induction r = -0.76; P = 0.002; STS 0.25 muM r = -0.62; P = 0.01). In addition, we found a negative correlation between percentages of cells with CC and regional brain volume in the right supratemporal cortex and post-central region (STS 0.25 and 0.5 muM; P < 0.05 family-wise error corrected (FWEc)). We reveal for the first time that peripheral markers of apoptotic susceptibility may correlate with brain metabolites, Glx and NAA, and regional brain volume in FES and controls, which is consistent with the neuroprogressive theories around the onset of the schizophrenia illness

Modeling dust and soluble iron deposition to the South Atlantic Ocean

International audienceThe global chemical transport model GEOS-Chem, implemented with a dust-iron dissolution scheme, was used to analyze the magnitude and spatial distribution of mineral dust and soluble-iron (sol-Fe) deposition to the South Atlantic Ocean (SAO). The comparison of model results with remotely sensed data shows that GEOS-Chem can capture dust source regions in Patagonia and characterize the temporal variability of dust outflow. For a year-long model simulation, 22 Tg of mineral dust and 4 Gg of sol-Fe were deposited to the surface waters of the entire SAO region, with roughly 30% of this dust and sol-Fe predicted to be deposited to possible high nitrate low chlorophyll oceanic regions. Model-predicted dissolved iron fraction of mineral dust over the SAO was small, on average only accounting for 0.57% of total iron. Simulations suggest that the primary reason for such a small fraction of sol-Fe is the low ambient concentrations of acidic trace gases available for mixing with dust plumes. Overall, the amount of acid added to the deliquesced aerosol solution was not enough to overcome the alkalinity buffer of Patagonian dust and initiate considerable acid dissolution of mineral-iron. Sensitivity studies show that the amount of sol-Fe deposited to the SAO was largely controlled by the initial amount of sol-Fe at the source region, with limited contribution from the spatial variability of Patagonian-desert topsoil mineralogy and natural sources of acidic trace gases. Simulations suggest that Patagonian dust should have a minor effect on biological productivity in the SAO

Biodiversity of the Regional Landscape Park Samara Plavni within the first large reservoir in Europe Biodiversity of the Regional Landscape Park Samara Plavni within the first large reservoir in Europe

The creation of reservoirs in river valleys for the accumulation of fresh water has been and remains an important issue around the world. This process has both positive and negative consequences for people and nature. Significant changes in the regime of rivers and their valleys, flooding of meadows and forests, flooding of soils and changes in the composition of flora and fauna of adjacent territories are taking place. In this article, we consider the restoration of the biodiversity of a site of disturbed lands after the creation of one of the first large reservoirs in Europe – the Dnieper (Zaporozhe) on the River Dnieper, which has existed since 1933. The territory of the Samara floodplains was formed on the floodplain of the mouth of the Samara River, as a result of which the territories of various forest, meadow and bog biotopes were flooded. For almost 90 years, new biotopes have been developing, and populations of plant and animal species, especially waterfowl, have been renewed and enriched. In the conditions of climate change and anthropogenic pressure, the existence of this territory has fallen into question. To control the conservation of biodiversity, it is necessary to apply various management methods, one of which is creation of nature reserves. The article presents the results of a complex of scientific studies that were carried out during the zoning of the regional park Samara Plavni to improve the management of the protection of water areas and river banks. We have investigated: hydrological features, species diversity of the flora and coenotic diversity of the vegetation, fauna of aquatic invertebrates, and terrestrial vertebrates. Zoning of the Regional Landscape Park was based on the composition of stable components of ecosystems. When applying the protected regime in different zones, conditions will be created for the preservation of habitats of species, including those protected in Europe: higher plants (Senecio borysthenicus (DC.) Andrz. ex Czern., Tragopogon borystenicus Artemcz.), reptiles (Emys orbicularis (Linnaeus, 1758), Vipera renardi (Christoph, 1861)), birds (Aythya ferina (Linnaeus, 1758), Vanellus vanellus (Linnaeus, 1758), Haematopus ostralegus Linnaeus, 1758, Numenius arquata (Linnaeus, 1758), Alcedo atthis (Linnaeus, 1758), Lanius excubitor (Linnaeus, 1758)), mammals (Lutra lutra (Linnaeus, 1758)). Such changes would increase the implementation of the reproductive potential of all species without exception in the studied ecosystems