Enterolobium cyclocarpum
is a characteristic legume tree species of seasonally dry tropical forests (SDTFs) of Mesoamerica and northern South America typically used in silvopastoral and agroforestry ...systems. Remaining populations of
E. cyclocarpum
in Colombia are severely fragmented owing to the highly degraded state of SDTF in the country, posing threats to both their in situ persistence and their usefulness as seed sources for future planting efforts. We genotyped
E. cyclocarpum
populations at nine sampling sites across a latitudinal gradient of SDTF in Colombia by means of eight nSSR markers to elucidate the species diversity distribution in the country. Our data suggest that a deep divide seems to have existed between Caribbean and Andean populations of
E. cyclocarpum
in Colombian SDTF that may date back to the last glacial maximum (~21,000 BP), or longer. However, we only found evidence of genetic differentiation between trees from the southern Cauca River valley and populations at more northern locations. All the latter populations showed signs of admixture which may be the result of human-influenced movement of germplasm, particularly after the introduction of cattle by European settlers. Most of the sampled sites showed heterozygosity scores close to Hardy–Weinberg expectations. Only the three southern-most populations displayed significantly positive values of inbreeding coefficient, potentially affecting their in situ maintenance and their use as seed sources. Based on our findings we identify priority areas for the in situ conservation of remaining
E. cyclocarpum
populations, and propose a strategy for sourcing of appropriate planting material for use in future tree planting efforts.
Water under subcritical conditions in a continuous-flow reactor (flash hydrolysis) has proved to be an efficient and environmentally friendly method for hydrolyzing proteins from microalgae biomass ...in a very short residence time (few seconds). In this study, flash hydrolysis experiments were conducted at three different temperatures (240, 280, and 320 °C) and three residence times (6, 9, and 12 s) to understand the kinetics of the hydrolysis of algae proteins to water-soluble peptides and arginine. Laboratory-grown protein-rich Scenedesmus sp. with an average composition of 54% proteins, 17% lipids, and 23% carbohydrates was used as the feedstock. After flash hydrolysis, both liquid and solid products were collected, and the contents of soluble peptides and arginine in the liquid fraction and of remaining proteinaceous material in the solids were analyzed. For all experiments above 240 °C at all residence times, the yield of soluble peptides was in the range of 57–67% of the algae protein, whereas the maximum arginine yield (81.51%) was achieved at 320 °C and a residence time of 6 s. The protein solubilization to soluble peptides fitted second-order reaction kinetics, whereas for arginine, the process was zeroth-order; the activation energies were calculated to be 43.0 and 34.1 kJ/mol, respectively. The results of this study suggest that flash hydrolysis can be an environmentally benign method for hydrolyzing proteins from microalgae to produce valuable coproducts such as arginine as a free amino acid and water-soluble peptides along with lipid-rich solids (biofuel intermediate) as a feedstock for biofuel production.
The ANTARES deep-sea neutrino telescope comprises a three-dimensional array of photomultipliers to detect the Cherenkov light induced by upgoing relativistic charged particles originating from ...neutrino interactions in the vicinity of the detector. The large scattering length of light in the deep sea facilitates an angular resolution of a few tenths of a degree for neutrino energies exceeding 10
TeV. In order to achieve this optimal performance, the time calibration procedures should ensure a relative time calibration between the photomultipliers at the level of ∼1
ns. The methods developed to attain this level of precision are described.
A study monitoring the brightness of stars in the Large Magellanic Cloud observed two possible microlensing events. Evidence indicates that the masses of lensing objects are equal to one solar mass ...or less.
Many proteins have been hypothesized to mediate intercellular interactions that regulate the formation, maturation, and maintenance of the skeletal neuromuscular junction. Three of the best ...characterized of these are a membrane-associated adhesion molecule, neural cell adhesion molecule (N-CAM), an extracellular matrix component, tenascin-C, and a soluble growth factor, fibroblast growth factor-5 (FGF-5). To assess the roles of these molecules in synaptogenesis in vivo, we examined neuromuscular junctions in homozygous mutant mice lacking N-CAM, tenascin-C, FGF-5, or both N-CAM and tenascin-C. End plates were 14% smaller in N-CAM-deficient mice than in controls, and formation of junctional folds was delayed in this mutant. In all other respects tested, however, the structure and molecular architecture of neuromuscular junctions were normal in all three single mutants and in the double mutant. We also tested the abilities of damaged motor axons to reinnervate mutant muscle after axotomy and of intact motor axons to sprout after partial denervation. Again, no significant differences among genotypes were observed. Together, these results demonstrate that N-CAM, tenascin-C, and FGF-5 are dispensable for major aspects of synaptic development and regeneration.
Agrin-induced clustering of acetylcholine receptors (AChRs) in the postsynaptic membrane is a key step in synaptogenesis at the neuromuscular junction. The receptor tyrosine kinase MuSK is a ...component of the agrin receptor, while the cytoplasmic protein rapsyn is necessary for the clustering of AChRs and all other postsynaptic membrane components studied to date. We show here that MuSK remains concentrated at synaptic sites in rapsyn-deficient mutant mice, suggesting that MuSK forms a primary structural scaffold to which rapsyn attaches other synaptic components. Using nonmuscle cells, we show that rapsyn–MuSK interactions are mediated by the ectodomain of MuSK, suggesting the existence of a transmembrane intermediate. In addition to rapsyn's structural role, we demonstrate that it is required for an early step in MuSK signaling, AChR phosphorylation. This signaling requires the kinase domain of MuSK, but not its ectodomain. Thus, MuSK may interact with rapsyn in multiple ways to play both structural and signaling roles in agrin-induced differentiation.
Sources of gravitational waves are often expected to be observable through several messengers, such as gamma-rays, X-rays, optical, radio, and/or neutrino emission. The simultaneous observation of ...electromagnetic or neutrino emission with a gravitational-wave signal could be a crucial aspect for the first direct detection of gravitational waves. Furthermore, combining gravitational waves with electromagnetic and neutrino observations will enable the extraction of scientific insight that was hidden from us before. We discuss the method that enables the joint search with the LIGO-Virgo-IceCube-ANTARES global network, as well as its methodology, science reach, and outlook for the next generation of gravitational-wave detectors.
Squid hydrolysates obtained by autolysis without addition of lactic acid at two different pH (5 and 7) and included at 25 and 50 g kg⁻¹ in a commercial shrimp feed were evaluated. Shrimp fed on such ...diets were cultured under indoor and outdoor conditions. Diets containing both hydrolysates and included at both levels caused a higher feed consumption by shrimp. In general, shrimp fed on both hydrolysates, but particularly on that prepared at pH 7, exhibited similar or better production responses (survival, biomass, feed conversion ratio, specific growth rate) compared to those fed on diets without the inclusion of hydrolysates. Shrimp cultured outdoor showed a better growth performance compared to those cultured indoor. No significant differences were found regarding the proximate composition of shrimp of any treatment. Results suggest that the free amino acids provided by squid hydrolysates contributed to improve the feed consumption and growth performance of shrimp cultured under both indoor and outdoor conditions.
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