Multi-messenger observations of a binary neutron star merger

On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta

Sele??o de clones de batata-doce para a regi?o do Alto Vale do Jequitinhonha

Com o objetivo de selecionar clones de batata-doce para a regi?o do alto Vale do Jequitinhonha, conduziu-se um experimento de dezembro de 2005 a julho de 2006, no CampusJK da Universidade Federal dos Vales do Jequitinhonha e Mucuri, UFVJM, munic?pio de Diamantina-MG. Foram avaliados nove clones de batata-doce pertencentes ao banco de germoplasma da UFVJM, juntamente com as cultivares Brazl?ndia Branca, Brazl?ndia Roxa e Princesa, utilizadas como testemunhas. O delineamento experimental utilizado foi blocos casualizados, com quatro repeti??es. A colheita foi realizada sete meses ap?s o plantio e foi avaliada a produtividade de massa verde e de ra?zes, al?m do formato e resist?ncia das ra?zes a insetos. Os gen?tipos n?o diferiram entre si em rela??o ? produtividade de massa verde, que variou de 3,81 a 11,76 t ha-1. A produ??o total de ra?zes variou de 22,0 a 45,4 t ha-1 e os clones BD-06, BD-113-TO, BD-15, BD-38, BD-25 e BD-61, al?m da cultivar Princesa, apresentaram os valores estatisticamente mais altos. Entretanto, apenas o clone BD-06 superou significativamente as cultivares testemunhas Brazl?ndia Branca e Brazl?ndia Roxa. O clone BD-06 apresentou tamb?m o maior valor absoluto para produ??o comercial de ra?zes (38,58 t.ha-1), estatisticamente similar ? maioria dos demais clones e tamb?m ? cultivar Princesa (35,87 t ha-1), mas superior ?s cultivares Brazl?ndia Branca e Brazl?ndia Roxa. A maioria dos clones avaliados, incluindo o clone BD-06, produziu ra?zes de bom formato e foram resistentes aos insetos de solo. Levando em conta os resultados obtidos, o clone BD-06 despontou como uma boa op??o para o cultivo de batata-doce no Alto Vale do Jequitinhonha.Funda??o de Amparo ? Pesquisa do Estado de Minas Gerais (FAPEMIG)Empresa de Pesquisa Agropecu?ria de Minas Gerais (EPAMIG)Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq)Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES)An experiment was carried out from December 2005 to July 2006, in the Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM), in Diamantina, Minas Gerais State, Brazil, aiming at selecting sweet potato clones for the Alto Vale do Jequitinhonha. We evaluated nine clones from the UFVJM germplasm bank, using cultivars Brazl?ndia Branca, Brazl?ndia Roxa, and Princesa as controls. The experimental design was blocks at random, with four replications. Plants were harvested seven months after transplanting. We assessed the fresh mass yield of vines and roots, as well as root shape and resistance to soil insects. Genotypes did not differ from each other for the fresh mass yield of vines (ranging from 3.81 to 11.76 t ha-1). The total yield of roots ranged from 22.0 to 45.4 t ha-1 and clones BD-06, BD-113-TO, BD-15, BD-38, BD-25, BD-61, and cultivar Princesa had statistically the highest figures. However, only clone BD-06 significantly overcame the control cultivars Brazl?ndia Branca and Brazl?ndia Roxa. Clone BD-06 had also the highest commercial yield of roots (38.58 t ha-1), statically similar to most of the other clones and cultivar Princesa (25.87 t ha-1), but superior to cultivars Brazl?ndia Branca and Brazl?ndia Roxa. Most of the clones tested, including clone BD-06, produced good shaped roots and were resistant to soil insects. Considering our results, clone BD-06 stood out as a good option for growing sweet potato in the Upper Valley of Jequitinhonha

The checkpoint-dependent nuclear accumulation of Rho1p exchange factor Rgf1p is important for tolerance to chronic replication stress

Guanine nucleotide exchange factors control many aspects of cell morphogenesis by turning on Rho-GTPases. The fission yeast exchange factor Rgf1p (Rho gef1) specifically regulates Rho1p during polarized growth and localizes to cortical sites. Here we report that Rgf1p is relocalized to the cell nucleus during the stalled replication caused by hydroxyurea (HU). Import to the nucleus is mediated by a nuclear localization sequence at the N-terminus of Rgf1p, whereas release into the cytoplasm requires two leucine-rich nuclear export sequences at the C-terminus. Moreover, Rgf1p nuclear accumulation during replication arrest depends on the 14-3-3 chaperone Rad24p and the DNA replication checkpoint kinase Cds1p. Both proteins control the nuclear accumulation of Rgf1p by inhibition of its nuclear export. A mutant, Rgf1p-9A, that substitutes nine serine potential phosphorylation Cds1p sites for alanine fails to accumulate in the nucleus in response to replication stress, and this correlates with a severe defect in survival in the presence of HU. In conclusion, we propose that the regulation of Rgf1p could be part of the mechanism by which Cds1p and Rad24p promote survival in the presence of chronic replication stress. It will be of general interest to understand whether the same is true for homologues of Rgf1p in budding yeast and higher eukaryotes

Discovering lactic acid bacteria by genomics

This review summarizes a collection of lactic acid bacteria that are now undergoing genomic sequencing and analysis. Summaries are presented on twenty different species, with each overview discussing the organisms fundamental and practical significance, environmental habitat, and its role in fermentation, bioprocessing, or probiotics. For those projects where genome sequence data were available by March 2002, summaries include a listing of key statistics and interesting genomic features. These efforts will revolutionize our molecular view of Gram-positive bacteria, as up to 15 genomes from the low GC content lactic acid bacteria are expected to be available in the public domain by the end of 2003. Our collective view of the lactic acid bacteria will be fundamentally changed as we rediscover the relationships and capabilities of these organisms through genomics.

Effects of habitat type change on taxonomic and functional composition of orchid bees (Apidae: Euglossini) in the Brazilian Amazon

© 2018, Springer International Publishing AG, part of Springer Nature. Land use change impact species richness and functional diversity (FD). In the Brazilian Amazon, we examined the impacts of oil palm plantations on orchid bee (Apidae: Euglossini) species using abundance and FD. We collected male orchid bees in oil palm plantation (PALM), legal reserves (LR), and riparian corridors (APP), and then we used morphological and life-history traits to characterize each species. We evaluated differences in bee body size by comparing intertegular span values. We tested the influence of habitat on taxonomic and functional parameters of orchid bees by applying a partial redundancy analysis (pRDA). We contrasted FD by calculating species richness, functional richness, and functional dispersion. We sampled 1176 bees from 30 species in 18 sampling days across 2015 and 2016. Males from PALM were 13.6% bigger than those in LR areas, and bees from APP showed a similar pattern compared to LR and PALM. Less than 15% of the variation in species composition was related to the distance among sampling sites, and 8% was due to habitat structure. In our pRDA, the spatial difference explained 6% of the variation in orchid bee traits, but there were no effects of habitat parameters upon FD. FD was reduced with land use change caused by oil palm plantations. Our findings support the belief that many bees are impacted by cultivated lands. Nevertheless, the functional similarity between LRs and APPs reflects common structural elements between them, although we did not find significant relationship between functional composition and habitat structure that we evaluated