Climate and environmental changes of the Lategacial transition and Holocene in northeastern Siberia: Evidence from diatom oxygen isotopes and assemblage composition at Lake Emanda

Indexación ScopusA new dataset from Lake Emanda provides insights into climate and environmental dynamics in an extreme continental setting in northeastern Siberia. The δ18Odiatom record is supported by diatom assemblage analysis, modern isotope hydrology and atmospheric circulation patterns. The data reveal a relatively cold oligotrophic freshwater lake system persisting for the last ∼13.2 cal ka BP. Most recent δ18Odiatom (+21.5‰) combined with present-day average δ18Olake (−16.5‰) allows calculating Tlake (∼21 °C), reflecting summer conditions. Nonetheless, the δ18Odiatom variability is associated with changes in δ18Olake rather than with Tlake. An obvious shift of ∼2‰ in the δ18Odiatom record at 11.7–11.5 cal ka BP accompanied by significant changes in diatom assemblages reflects the onset of the Holocene. Relatively high δ18Odiatom during the Early Holocene suggests relatively warm and/or dry climate with associated evaporation effects. The absolute maximum in δ18Odiatom of +27.7‰ consistent with high values of diatom indices at ∼7.9–7.0 cal ka BP suggests a Mid Holocene Thermal Maximum. A continuous depletion in δ18Odiatom since ∼5.0 cal ka BP is interpreted as Middle to Late Holocene cooling reaching the absolute minimum at 0.4 cal ka BP (i.e. the Little Ice Age). An overall cooling trend (∼0.3‰ 1000 yr−1) throughout the Holocene follows decreasing solar insolation. The pattern of the Lake Emanda δ18Odiatom record is similar to that obtained from Lake El'gygytgyn suggesting a common “eastern” regional signal in both records, despite their hydrological differences. Presently, atmospheric moisture reaches the study region from the west and east with ∼40% each, as well as ∼20% from the north. © 2021 The Author(s)https://www-sciencedirect-com.recursosbiblioteca.unab.cl/science/article/pii/S0277379121001128?via%3Dihu

High-quality permanent draft genome sequence of the Mimosa asperata - nodulating Cupriavidus sp strain AMP6

Cupriavidus sp. strain AMP6 is an aerobic, motile, Gram-negative, non-spore-forming rod that was isolated from a root nodule of Mimosa asperata collected in Santa Ana National Wildlife Refuge, Texas, in 2005. Mimosa asperata is the only legume described so far to exclusively associates with Cupriavidus symbionts. Moreover, strain AMP6 represents an early-diverging lineage within the symbiotic Cupriavidus group and has the capacity to develop an effective nitrogen-fixing symbiosis with three other species of Mimosa. Therefore, the genome of Cupriavidus sp. strain AMP6 enables comparative analyses of symbiotic trait evolution in this genus and here we describe the general features, together with sequence and annotation. The 7,579,563 bp high-quality permanent draft genome is arranged in 260 scaffolds of 262 contigs, contains 7,033 protein-coding genes and 97 RNA-only encoding genes, and is part of the GEBA-RNB project proposal

High-quality permanent draft genome sequence of the Mimosa asperata - nodulating Cupriavidus sp strain AMP6

Cupriavidus sp. strain AMP6 is an aerobic, motile, Gram-negative, non-spore-forming rod that was isolated from a root nodule of Mimosa asperata collected in Santa Ana National Wildlife Refuge, Texas, in 2005. Mimosa asperata is the only legume described so far to exclusively associates with Cupriavidus symbionts. Moreover, strain AMP6 represents an early-diverging lineage within the symbiotic Cupriavidus group and has the capacity to develop an effective nitrogen-fixing symbiosis with three other species of Mimosa. Therefore, the genome of Cupriavidus sp. strain AMP6 enables comparative analyses of symbiotic trait evolution in this genus and here we describe the general features, together with sequence and annotation. The 7,579,563 bp high-quality permanent draft genome is arranged in 260 scaffolds of 262 contigs, contains 7,033 protein-coding genes and 97 RNA-only encoding genes, and is part of the GEBA-RNB project proposal

High-quality permanent draft genome sequence of the Mimosa asperata - nodulating Cupriavidus sp strain AMP6

Cupriavidus sp. strain AMP6 is an aerobic, motile, Gram-negative, non-spore-forming rod that was isolated from a root nodule of Mimosa asperata collected in Santa Ana National Wildlife Refuge, Texas, in 2005. Mimosa asperata is the only legume described so far to exclusively associates with Cupriavidus symbionts. Moreover, strain AMP6 represents an early-diverging lineage within the symbiotic Cupriavidus group and has the capacity to develop an effective nitrogen-fixing symbiosis with three other species of Mimosa. Therefore, the genome of Cupriavidus sp. strain AMP6 enables comparative analyses of symbiotic trait evolution in this genus and here we describe the general features, together with sequence and annotation. The 7,579,563 bp high-quality permanent draft genome is arranged in 260 scaffolds of 262 contigs, contains 7,033 protein-coding genes and 97 RNA-only encoding genes, and is part of the GEBA-RNB project proposal

High-quality permanent draft genome sequence of the Mimosa asperata - nodulating Cupriavidus sp strain AMP6

Cupriavidus sp. strain AMP6 is an aerobic, motile, Gram-negative, non-spore-forming rod that was isolated from a root nodule of Mimosa asperata collected in Santa Ana National Wildlife Refuge, Texas, in 2005. Mimosa asperata is the only legume described so far to exclusively associates with Cupriavidus symbionts. Moreover, strain AMP6 represents an early-diverging lineage within the symbiotic Cupriavidus group and has the capacity to develop an effective nitrogen-fixing symbiosis with three other species of Mimosa. Therefore, the genome of Cupriavidus sp. strain AMP6 enables comparative analyses of symbiotic trait evolution in this genus and here we describe the general features, together with sequence and annotation. The 7,579,563 bp high-quality permanent draft genome is arranged in 260 scaffolds of 262 contigs, contains 7,033 protein-coding genes and 97 RNA-only encoding genes, and is part of the GEBA-RNB project proposal

Nucleation versus Spinodal decomposition in a first order quark hadron phase transition

We investigate the scenario of homogeneous nucleation for a first order quark-hadron phase transition in a rapidly expanding background of quark gluon plasma. Using an improved preexponential factor for homogeneous nucleation rate, we solve a set of coupled equations to study the hadronization and the hydrodynamical evolution of the matter. It is found that significant supercooling is possible before hadronization begins. This study also suggests that spinodal decomposition competes with nucleation and may provide an alternative mechanism for phase conversion particularly if the transition is strong enough and the medium is nonviscous. For weak enough transition, the phase conversion may still proceed via homogeneous nucleation.Comment: LaTeX, 10 pages with 7 Postscript figures, more discussions and referencese added, typos correcte

Hydrogen a relevant shallow donor in Zinc Oxide

Biological and Soft Matter Physic

Neurotoxic astrocytes directly converted from sporadic and familial ALS patient fibroblasts reveal signature diversities and miR-146a theragnostic potential in specific subtypes

A lack of stratification methods in patients with amyotrophic lateral sclerosis (ALS) is likely implicated in therapeutic failures. Regional diversities and pathophysiological abnormalities in astrocytes from mice with SOD1 mutations (mSOD1-ALS) can now be explored in human patients using somatic cell reprogramming. Here, fibroblasts from four sporadic (sALS) and three mSOD1-ALS patients were transdifferentiated into induced astrocytes (iAstrocytes). ALS iAstrocytes were neurotoxic toward HB9-GFP mouse motor neurons (MNs) and exhibited subtype stratification through GFAP, CX43, Ki-67, miR-155 and miR-146a expression levels. Up- (two cases) and down-regulated (three cases) miR-146a values in iAstrocytes were recapitulated in their secretome, either free or as cargo in small extracellular vesicles (sEVs). We previously showed that the neuroprotective phenotype of depleted miR-146 mSOD1 cortical astrocytes was reverted by its mimic. Thus, we tested such modulation in the most miR-146a-depleted patient-iAstrocytes (one sALS and one mSOD1-ALS). The miR-146a mimic in ALS iAstrocytes counteracted their reactive/inflammatory profile and restored miR-146a levels in sEVs. A reduction in lysosomal activity and enhanced synaptic/axonal transport-related genes in NSC-34 MNs occurred after co-culture with miR-146a-modulated iAstrocytes. In summary, the regulation of miR-146a in depleted ALS astrocytes may be key in reestablishing their normal function and in restoring MN lysosomal/synaptic dynamic plasticity in disease sub-groups

Dynamic model of basic oxygen steelmaking process based on multi-zone reaction kinetics : model derivation and validation

A multi-zone kinetic model coupled with a dynamic slag generation model was developed for the simulation of hot metal and slag composition during the BOF operation. The three reaction zones, (i) jet impact zone (ii) slag-bulk metal zone (iii) slag-metal-gas emulsion zone were considered for the calculation of overall refining kinetics. In the rate equations, the transient rate parameters were mathematically described as a function of process variables. A micro and macroscopic rate calculation methodology (micro-kinetics and macro-kinetics) were developed to estimate the total refining contributed by the recirculating metal droplets through the slag-metal emulsion zone. The micro-kinetics involves developing the rate equation for individual droplets in the emulsion. The mathematical models for the size distribution of initial droplets, kinetics of simultaneous refining of elements, the residence time in the emulsion, dynamic interfacial area change were established in the micro-kinetic model. In the macro-kinetics calculation, a droplet generation model was employed and the total amount of refining by emulsion was calculated by summing the refining from the entire population of returning droplets. A dynamic FetO generation model based on oxygen mass balance was developed and coupled with the multi-zone kinetic model. The effect of post combustion on the evolution of slag and metal composition was investigated. The model was applied to a 200-ton top blowing converter and the simulated value of metal and slag was found to be in good agreement with the measured data. The post-combustion ratio was found to be an important factor in controlling FetO content in the slag and the kinetics of Mn and P in a BOF process

Translating SOD1 gene silencing towards the clinic: A highly efficacious, off-target free and biomarker-supported strategy for familial ALS

Twenty per cent of familial amyotrophic lateral sclerosis (fALS) cases are caused by mutations in the gene encoding human cytosolic Cu/Zn superoxide dismutase (hSOD1). Efficient translation of the therapeutic potential of interfering RNA (RNAi) for the treatment of SOD1-ALS patients requires the development of vectors that are free of significant off-target effects and with reliable biomarkers to discern sufficient target engagement and correct dosing. Using adeno-associated virus serotype 9 to deliver RNAi against hSOD1 in the SOD1G93A mouse model, we found that intrathecal injection of the therapeutic vector via the cisterna magna delayed onset of disease, decreased motor neuron death at end stage by up to 88% and prolonged the median survival of SOD1G93A mice by up to 42%. To our knowledge this is the first report to demonstrate no significant off-target effects linked to hSOD1 silencing, providing further confidence in the specificity of this approach. We also report the measurement of cerebrospinal fluid (CSF) hSOD1 protein levels as a biomarker of effective dosing and efficacy of hSOD1 knockdown. Together, these data provide further confidence in the safety of the clinical therapeutic vector. The CSF biomarker will be a useful measure of biological activity for translation into human clinical trials