Optical constraints of kerogen from 0.15 to 40 microns: Comparison with meteoritic organics

Kerogens are dark, complex organic materials produced on the Earth primarily by geologic processing of biologic materials, but kerogens have chemical and spectral similarities to some classes of highly processed extraterrestrial organic materials. Kerogen-like solids were proposed as constitutents of the very dark reddish surfaces of some asteroids and are also spectrally similar to some carbonaceous organic residues and the Iapetus dark material. Kerogen can thus serve as a useful laboratory analog to very dark, spectrally red extraterrestrial materials; its optical constants can be used to investigate the effects of particle size, void space and mixing of bright and dark components in models of scattering by dark asteroidal, cometary, and satellite surfaces. Measurements of the optical constants of both Type 2 kerogen and of macromolecular organic residue from the Murchison carbonaceous chondrite via transmission and reflection measurements on thin films are reported. The real part of the refractive index, n, is determined by variable incidence-angle reflectance to be 1.60 + or - 0.05 from 0.4 to 2.0 micrometers wavelength. Work extending the measurement of n to longer wavelengths is in progress. The imaginary part of the refractive index, k, shows substantial structure from 0.15 to 40 micrometers. The values are accurate to + or - 20 percent in the UV and IR regions and to + or - 30 percent in the visible. The k values of organic residues were also measured from the Murchison meteorite. Comparison of the kerogen and Murchison data reveals that between 0.15 and 40 microns, Murchison has a similar structure but no bands as sharp as in kerogen, and that the k values for Murchison are significantly higher than those of kerogen

Staphylococcus aureus Panton‐Valentine Leukocidin triggers an alternative NETosis process targeting mitochondria

Panton-Valentine Leukocidin (PVL) is a bicomponent leukotoxin produced by 3%-10% of clinical Staphylococcus aureus (SA) strains involved in the severity of hospital and community-acquired infections. Although PVL was long known as a pore-forming toxin, recent studies have challenged the formation of a pore at the plasma membrane, while its endocytosis and the exact mode of action remain to be defined. In vitro immunolabeling of human neutrophils shows that Neutrophil Extracellular Traps (NETosis) is triggered by the action of purified PVL, but not by Gamma hemolysin CB (HlgCB), a structurally similar SA leukotoxin. PVL causes the ejection of chromatin fibers (NETs) decorated with antibacterial peptides independently of the NADPH oxidase oxidative burst. Leukotoxin partially colocalizes with mitochondria and enhances the production of reactive oxygen species from these organelles, while showing an increased autophagy, which results unnecessary for NETs ejection. PVL NETosis is elicited through Ca2+-activated SK channels and Myeloperoxidase activity but is abolished by Allopurinol pretreatment of neutrophils. Moreover, massive citrullination of the histone H3 is performed by peptidyl arginine deiminases. Inhibition of this latter enzymes fails to abolish NET extrusion. Unexpectedly, PVL NETosis does not seem to involve Src kinases, which is the main kinase family activated downstream the binding of PVL F subunit to CD45 receptor, while the specific kinase pathway differs from the NADPH oxidase-dependent NETosis. PVL alone causes a different and specific form of NETosis that may rather represent a bacterial strategy conceived to disarm and disrupt the immune response, eventually allowing SA to spread

Population genetic of Atlantic bonito in the north east Atlantic and Mediterranean

This study assesses the stock structure of Atlantic bonito (Sarda sarda) using the mitochondrial control region as a genetic marker. About 615 individuals distributed in seven locations were analyzed. Two of the locations were in the Mediterranean Sea (MD/BIL95) (Spain and Tunis), three in the northeast Atlantic (AT-NE/BIL94B) (Portugal, Tunis, Morocco and Mauritania), and one in the southeast Atlantic (AT-SE/BIL97) (Côte d’Ivoire). All these samples were obtained thanks to the participation of all authors in two Small Tuna Research Programs funded by ICCAT. The analysis of the genetic variability of the sequence of mitochondrial control regions depicts a clear heterogeneity among locations. The shared genetic pool that comprises the locations within the Mediterranean (Spain and Tunis), including also a sample from the northeast Atlantic (Portugal), is clearly different from the African locations (Senegal and Côte d’Ivoire). Moreover, these two African locations are also genetically differentiated between them. Morocco and Mauritania locations seems to be located in an intermediate situation between these two groups of locations. These results can be used to infer a management policy by ICCAT on the fisheries of this specie

Final report of the short-term contract for ICCAT SMYTP for the biological samples collection for growth, maturity and genetics studies – Year #2

This document is the final report of the second year of the short-term contract of the Small Tuna Year Program by ICCAT. In 2018, the Small Tuna Species Group decided to prioritize Little tunny (LTA) (Euthynnus alletteratus) Atlantic bonito (BON) (Sarda sarda) and Wahoo (WAH) (Acanthocybium solandri), based on their economic importance and the deficiency of knowledge of their biology. The objectives of the contract for three species were: i) Collect biological samples for estimating growth parameters, assessing the maturity and stock structure analysis (populations genetics), and ii) Conclude the analysis of the stock structure for at least one of the three species and provide preliminary results for the remaining. The obtained samples for growth, maturity and stock structure analysis was almost completed for Little tunny and Atlantic bonito, whereas for Wahoo the samples are scarce. The analysis of stock structure for Little tunny and Atlantic bonito revealed that the observed dif

Population genetic of Atlantic bonito in the north east Atlantic and Mediterranean

This study assesses the stock structure of Atlantic bonito (Sarda sarda) using the mitochondrial control region as a genetic marker. About 615 individuals distributed in seven locations were analyzed. Two of the locations were in the Mediterranean Sea (MD/BIL95) (Spain and Tunis), three in the northeast Atlantic (AT-NE/BIL94B) (Portugal, Tunis, Morocco and Mauritania), and one in the southeast Atlantic (AT-SE/BIL97) (Côte d’Ivoire). All these samples were obtained thanks to the participation of all authors in two Small Tuna Research Programs funded by ICCAT. The analysis of the genetic variability of the sequence of mitochondrial control regions depicts a clear heterogeneity among locations. The shared genetic pool that comprises the locations within the Mediterranean (Spain and Tunis), including also a sample from the northeast Atlantic (Portugal), is clearly different from the African locations (Senegal and Côte d’Ivoire). Moreover, these two African locations are also genetically differentiated between them. Morocco and Mauritania locations seems to be located in an intermediate situation between these two groups of locations. These results can be used to infer a management policy by ICCAT on the fisheries of this specie

AMP kinase–mediated activation of the BH3-only protein Bim couples energy depletion to stress-induced apoptosis

Disturbances in cellular ion gradients by excitotoxicity promote apoptosis through activation of the Bcl-2 family member Bim

Two step activation of FOXO3 by AMPK generates a coherent feed-forward loop determining excitotoxic cell fate

Cerebral ischemia and excitotoxic injury induce transient or permanent bioenergetic failure, and may result in neuronal apoptosis or necrosis. We have previously shown that ATP depletion and activation of AMP-activated protein kinase (AMPK) during excitotoxic injury induces neuronal apoptosis by transcription of the proapoptotic BH3 only protein, Bim. AMPK, however, also exerts pro-survival functions in neurons. The molecular switches that determine these differential outcomes are not well understood. Using an approach combining biochemistry, single cell imaging and computational modeling, we here demonstrate that excitotoxic injury activated the bim promoter in a FOXO3-dependent manner. The activation of AMPK reduced AKT activation, and led to dephosphorylation and nuclear translocation of FOXO3. Subsequent mutation studies indicated that bim gene activation during excitotoxic injury required direct FOXO3 phosphorylation by AMPK in the nucleus as a second activation step. Inhibition of this phosphorylation prevented Bim expression and protected neurons against excitotoxic and oxygen/glucose deprivation-induced injury. Systems analysis and computational modeling revealed that these two activation steps defined a coherent feedforward loop; a network motif capable of filtering any effects of short-term AMPK activation on bim gene induction. This may prevent unwanted AMPK-mediated Bim expression and apoptosis during transient or physiological bioenergetic stress

Final report of the short-term contract for ICCAT SMYTP for the biological samples collection for growth, maturity and genetics studies – Year #2

This document is the final report of the second year of the short-term contract of the Small Tuna Year Program by ICCAT. In 2018, the Small Tuna Species Group decided to prioritize Little tunny (LTA) (Euthynnus alletteratus) Atlantic bonito (BON) (Sarda sarda) and Wahoo (WAH) (Acanthocybium solandri), based on their economic importance and the deficiency of knowledge of their biology. The objectives of the contract for three species were: i) Collect biological samples for estimating growth parameters, assessing the maturity and stock structure analysis (populations genetics), and ii) Conclude the analysis of the stock structure for at least one of the three species and provide preliminary results for the remaining. The obtained samples for growth, maturity and stock structure analysis was almost completed for Little tunny and Atlantic bonito, whereas for Wahoo the samples are scarce. The analysis of stock structure for Little tunny and Atlantic bonito revealed that the observed dif

Photographs of the Legendary Tempelhof Airport

Classified as a historical monument, it is the worldis third biggest building and was once the oldest airport in service. In accordance with the designs of Ernst Sagebiel, a student of Erich Mendelsohn, construction work started in 1936. The outbreak of the Second World War prevented the completion of the building project. After the war, the area became an American military base, gaining international fame in the postwar period, thanks to the Allied airlift Luftbru_cke