Post‐fire recovery occurs overwhelmingly by resprouting in the Chaco Serrano forest of Central Argentina

In fire‐prone landscapes, differences in post‐fire regeneration by resprouting between species or sites could be far more important in explaining vegetation physiognomy and composition than seed regeneration. This is the first study exploring the relative contribution of tree resprouts and seeds to post‐fire crown volume in the Chaco Serrano forest of South America. Additionally, we compare the resprouting response among species and quantify post‐fire changes in tree composition among sites. We established 290 permanent plots distributed in three sites affected by wildfires in 2005. For all tree species in all plots we recorded survival of every individual 1 year after the fire; at the plot level, we recorded the above‐ground tree volume before and 3 years after the fire. Resprouting from the base was the main resprouting type. Survival varied between species from 73% to 100% for native species and from 7% to 100% for non‐natives. Before the fire, crown volume was similar in the three sites, and was completely lost after the fire in 92% of the plots. Three years after the fire, between 8% and 58% of crown volume was recovered. The ratio of crown recovery because of resprouts and seedlings was 1562:1. Tree composition exhibited few changes because of the high post‐fire survival of most native species. We conclude that in the semiarid Chaco Serrano ecosystem tree species regenerate mainly by resprouting. This regeneration mode should be taken into account to better understand post‐fire successional pathways of these forests, their management and the restoration of burnt forest areas.     

Improving material efficiency in the life cycle of products: a review of EU Ecolabel criteria

The International Journal of Life Cycle Assessment - Material efficiency encompasses a range of strategies that support a reduction of material consumption and waste production from a...     

Fluorine‐Free Noble Salt Anion for High‐Performance All‐Solid‐State Lithium–Sulfur Batteries

Amongst post‐Li‐ion battery technologies, lithium–sulfur (Li–S) batteries have captured an immense interest as one of the most appealing devices from both the industrial and academia sectors. The replacement of conventional liquid electrolytes with solid polymer electrolytes (SPEs) enables not only a safer use of Li metal (Li°) anodes but also a flexible design in the shape of Li–S batteries. However, the practical implementation of SPEs‐based all‐solid‐state Li–S batteries (ASSLSBs) is largely hindered by the shuttling effect of the polysulfide intermediates and the formation of dendritic Li° during the battery operation. Herein, a fluorine‐free noble salt anion, tricyanomethanide [C(CN)₃^?, TCM^?], is proposed as a Li‐ion conducting salt for ASSLSBs. Compared to the widely used perfluorinated anions {e.g., bis(trifluoromethanesulfonyl)imide anion, [N(SO₂CF₃)₂)]^?, TFSI^?}, the LiTCM‐based electrolytes show decent ionic conductivity, good thermal stability, and sufficient anodic stability suiting the cell chemistry of ASSLSBs. In particular, the fluorine‐free solid electrolyte interphase layer originating from the decomposition of LiTCM exhibits a good mechanical integrity and Li‐ion conductivity, which allows the LiTCM‐based Li–S cells to be cycled with good rate capability and Coulombic efficiency. The LiTCM‐based electrolytes are believed to be the most promising candidates for building cost‐effective and high energy density ASSLSBs in the near future.     

The TT Genotype of the STAT4 rs7574865 Polymorphism Is Associated with High Disease Activity and Disability in Patients with Early Arthritis

Background

The number of copies of the HLA-DRB1 shared epitope, and the minor alleles of the STAT4 rs7574865 and the PTPN22 rs2476601 polymorphisms have all been linked with an increased risk of developing rheumatoid arthritis. In the present study, we investigated the effects of these genetic variants on disease activity and disability in patients with early arthritis.

Methodology and Results

We studied 640 patients with early arthritis (76% women; median age, 52 years), recording disease-related variables every 6 months during a 2-year follow-up. HLA-DRB1 alleles were determined by PCR-SSO, while rs7574865 and rs2476601 were genotyped with the Taqman 5′ allelic discrimination assay. Multivariate analysis was performed using generalized estimating equations for repeated measures. After adjusting for confounding variables such as gender, age and ACPA, the TT genotype of rs7574865 in STAT4 was associated with increased disease activity (DAS28) as compared with the GG genotype (β coefficient [95% confidence interval] = 0.42 [0.01–0.83], p = 0.044). Conversely, the presence of the T allele of rs2476601 in PTPN22 was associated with diminished disease activity during follow-up in a dose-dependent manner (CT genotype = −0.27 [−0.56– −0.01], p = 0.042; TT genotype = −0.68 [−1.64– −0.27], p = 0.162). After adjustment for gender, age and disease activity, homozygosity for the T allele of rs7574865 in STAT4 was associated with greater disability as compared with the GG genotype.

Conclusions

Our data suggest that patients with early arthritis who are homozygous for the T allele of rs7574865 in STAT4 may develop a more severe form of the disease with increased disease activity and disability.     

Physiological and molecular mechanisms underlying the integration of light and temperature cues in Arabidopsis thaliana seeds

The relief of dormancy and the promotion of seed germination are of extreme importance for a successful seedling establishment. Although alternating temperatures and light are signals promoting the relief of seed dormancy, the underlying mechanisms of their interaction in seeds are scarcely known. By exposing imbibed Arabidopsis thaliana dormant seeds to two‐day temperature cycles previous of a red light pulse, we demonstrate that the germination mediated by phytochrome B requires the presence of functional PSEUDO‐RESPONSE REGULATOR 7 (PRR7) and TIMING OF CAB EXPRESSION 1 (TOC1) alleles. In addition, daily cycles of alternating temperatures in darkness reduce the protein levels of DELAY OF GERMINATION 1 (DOG1), allowing the expression of TOC1 to induce seed germination. Our results suggest a functional role for some components of the circadian clock related with the action of DOG1 for the integration of alternating temperatures and light signals in the relief of seed dormancy. The synchronization of germination by the synergic action of light and temperature through the activity of circadian clock might have ecological and adaptive consequences.     

Plant Conservation in the Caribbean Island Biodiversity Hotspot

While the Caribbean is a recognized “biodiversity hotspot”, plant conservation has not received adequate attention; particularly, given the high levels of endemism in many plant groups. Besides establishing protected areas, there needs to be a sustained effort to study the taxonomy, systematics and ecology of the flora. Recent phylogenetic studies have shown high levels of endemism and conservation studies indicate a large propotion of the flora is threatened with extinction. Eight recommendations are given for plant conservation in the region.     

Arabidopsis cryptochrome 2 completes its posttranslational life cycle in the nucleus

CRY2 is a blue light receptor regulating light inhibition of hypocotyl elongation and photoperiodic flowering in Arabidopsis thaliana. The CRY2 protein is found primarily in the nucleus, and it is known to undergo blue light-dependent phosphorylation and degradation. However, the subcellular location where CRY2 exerts its function or undergoes blue light-dependent phosphorylation and degradation remains unclear. In this study, we analyzed the function and regulation of conditionally nuclear-localized CRY2. Our results show that CRY2 mediates blue light inhibition of hypocotyl elongation and photoperiodic promotion of floral initiation in the nucleus. Consistent with this result and a hypothesis that blue light-dependent phosphorylation is associated with CRY2 function, we demonstrate that CRY2 undergoes blue light-dependent phosphorylation in the nucleus. CRY2 phosphorylation is required for blue light-dependent CRY2 degradation, but only a limited quantity of CRY2 is phosphorylated at any given moment in seedlings exposed to blue light, which explains why continuous blue light illumination is required for CRY2 degradation. Finally, we showed that CRY2 is ubiquitinated in response to blue light and that ubiquitinated CRY2 is degraded by the 26S proteasome in the nucleus. These findings demonstrate that a photoreceptor can complete its posttranslational life cycle (from protein modification, to function, to degradation) inside the nucleus.     

Discovery of an ebolavirus-like filovirus in europe

Filoviruses, amongst the most lethal of primate pathogens, have only been reported as natural infections in sub-Saharan Africa and the Philippines. Infections of bats with the ebolaviruses and marburgviruses do not appear to be associated with disease. Here we report identification in dead insectivorous bats of a genetically distinct filovirus, provisionally named Lloviu virus, after the site of detection, Cueva del Lloviu, in Spain.     

Cognitive impairment and the risk of falling in the elderly

Risk of fall is significantly increased in old people with cognitive decline due to specific associations between gait parameters and cognition. This association has recently been demonstrated, there being increasing evidence that cognitive domains such as attention, executive function and types of memory are critical for the correct regulation of gait. Gait disturbances can appear as early predictors of dementia in elderly patients. In the assessment of the fall risk, the use of dual tasks is novel, simple and relevant, especially in cognitive decline. Evidence for interventions in this population is limited, with vitamin D and physical exercise being the most encouraging, for decreasing the risk of fall in dementia.