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

Reply: Genetic polymorphisms and cerebrovascular disease in children with sickle cell anemia from Rio de Janeiro, Brazil

The aim of the present work was to examine possible genetic risk factors related to the occurrence of cerebrovascular disease (CVD) in Brazilian population, the frequency of βS-globin gene haplotypes and co-inheritance with α-thalassemia (-α3.7kb) and single nucleotide polymorphism of methylenetetrahydrofolate reductase (MTHFR-C677T), Factor V Leiden (FV-G1691A) and prothrombin (PT-G20210A) genes in children from Rio de Janeiro. Ninety four children with sickle cell anemia (SCA) were included, 24 patients with cerebrovascular involvement and 70 patients without CVD as control group. The mean age of children at the time of the cerebrovascular event was similar to the control group. The frequency of -α3.7kb thalassemia was similar in both groups (p=0.751). Children with Bantu/Atypical βS-globin gene haplotype presented 15 times more chance (OR=15.4 CI 95% 2.9-81.6) of CVD than the other βS-globin gene haplotypes. The C677T polymorphism of MTHFR gene was similar in both groups (p=0.085). No mutation in the FV Leiden or PT genes was found. A large study seems necessary to establish the role of these genetic polymorphisms in Brazilian miscegenated population

Caracterização da função mastigatória em crianças com dentição decídua e dentição mista Characteristics of masticatory function in children with deciduous and mixed dentition

OBJETIVO: caracterizar a mastigação de crianças com dentição decídua e com dentição mista, buscando verificar se há variações inerentes ao processo de desenvolvimento desta função. MÉTODOS: participaram 78 crianças, 4 a 11 anos, ambos os gêneros, divididas em dois grupos: GI - dentição decídua completa e GII - dentição mista. Foi realizada inspeção visual das estruturas do sistema estomatognático seguida da avaliação da mastigação, utilizando-se pão francês. A coleta dos dados foi realizada por meio da observação visual direta e registro em vídeo, visando confirmação dos dados observados, analisando-se os seguintes dados durante a mastigação: tipo de mordida, postura de lábios, amassamento com a língua, quantidade ingerida, padrão mastigatório, ciclos mastigatórios, movimentos mandibulares, uso dos dedos para juntar o alimento e verificação de movimentação exagerada da musculatura perioral. RESULTADOS: pode-se considerar que crianças de G1 e G2 apresentam as seguintes características: mordida frontal, porção média de alimento, presença de vedamento labial, média de 27 ciclos mastigatórios por porção, movimentos mandibulares rotatórios, ausência de amassamento do alimento com a língua, ausência da utilização dos dedos para juntar o alimento e ausência de uso exagerado da musculatura perioral. Não foram encontradas diferenças estatisticamente significantes entre as características mastigatórias dos dois grupos, sendo que apenas a presença de amassamento do alimento com a língua é predominante na dentição decídua. CONCLUSÃO: parece não existir diferenciação das características quanto ao padrão mastigatório em relação às fases de dentição estudadas, sendo apenas o amassamento do alimento mais frequente na decídua.<br>PURPOSE: to raise and to characterize the chewing pattern in children with deciduous and mixed dentition. METHODS: 78 children, from 4 to 11-year old, both genders, divided in two groups: GI: children with complete deciduous dentition and GII: with mixed dentition. Visual inspection of the stomatognathic system was followed by the evaluation of chewing, using three portions of French bread, with the first portion ignored. Data analysis was carried through visual observation and video recording, in order to review and confirm the observed characteristics. The following items were analyzed: type of bite, lips' position, kneading with the tongue, ingested amount, chewing pattern, number of chewing cycles, mandibular movements, the use of fingers to join food and verification of overstated movement of the perioral muscles. RESULTS: we can consider that children of GI and GII have the following characteristics: frontal bite, regular amount of food, presence of lips closed, average of 27 chewing cycles for portion, rotatory mandible movements, absence of food tongue kneading, no use of fingers to join the food and no overstated movements of the perioral muscles. Significant statistical differences were not found between the two groups. Only the presence of kneading food with the tongue is more common in deciduous dentition. CONCLUSION: it seems that there are no differences of the chewing pattern characteristics in relation to the dentition phase, considering deciduous or mixed dentition, excepting food kneading with the tongue that is more frequent in deciduous dentition

Análise comparativa da mastigação de crianças respiradoras nasais e orais com dentição decídua Comparative analysis of mastication in children with nasal and mouth breathing with first teething

OBJETIVO: investigar as possíveis alterações, causadas pelo modo respiratório, na mastigação de crianças com dentição decídua completa, respiradoras orais e nasais. MÉTODOS: participaram da pesquisa 46 crianças (23 respiradoras nasais - RN e 23 respiradoras orais - RO) matriculadas em duas escolas públicas de Educação Infantil de São Caetano do Sul. Foi aplicado um questionário aos pais para coletar dados sobre a respiração das crianças, os quais foram relacionados aos achados da avaliação oromiofuncional que constatou o modo respiratório. A amostra foi dividida nos grupos RO e RN e realizada avaliação da mastigação de pão francês (por meio de observação direta e análise de vídeo-gravação). RESULTADOS: foi encontrada mordida frontal em 91,3% dos RN e 82,6% dos RO; mastigação bilateral alternada em 78,3% dos RN e 87,0% dos RO; movimentos verticais e rotatórios em 95,7% dos RN e 100% dos RO; tempo médio de mastigação de 24,10 seg. nos RN e 15,92 seg. nos RO; volume médio ingerido em 73,9% para ambos os grupos; ausência de alimento no vestíbulo bucal em 73,9% dos RN e 39,1% dos RO; ausência de ruído em 91,3% dos RN e 60,9% dos RO; lábios abertos em 4,3% dos RN e 56,5% dos RO; simetria dos músculos masseter e temporal em 100% nos dois grupos. CONCLUSÃO: houve diferença estatisticamente significante na comparação dos modos respiratórios evidenciando que o modo interfere negativamente na mastigação do respirador oral quanto aos aspectos: tempo mastigatório, sobras de alimento na cavidade oral, postura dos lábios e ruído durante a mastigação.<br>PURPOSE: to investigate the possible alterations caused by breathing modus in mastication in a group of children with complete first teething, nasal and mouth breathing. Method: 46 children took part in this investigation (23 children were nasal breathing- NB and 23 children mouth breathing- MB). Children were enrolled in two public kindergartens in São Caetano do Sul. Their parents were asked to fill out a form in order to collect information about their children's breathing. This data was related with oral miofunctional evaluation to check the children's breathing modus. NB and MB groups were formed and a mastication function evaluation was carried out by observation means and videoing the children while they were masticating French bread. RESULTS: fontal bite: NB, 91.3%; MB, 82.6%. Alternate bilateral mastication: NB, 78.3%; MB, 82.0%. Vertical and rotating movements: NB, 95.7%; MB, 100%. Average time of mastication of NB group: 24.0 sec.; average time of MB group: 15.9 sec. Symmetry of average volume taken: NB, 73.9%; MB, 73.9%. Without any residue of food: NB, 73.9%; MB, 39.1%. Absence of noise: NB, 91.3%; MB, 60.9%. Open lips: NB, 4.3%; MB, 56.5%; Symmetry of masseter and temporalis muscles: NB, 100%; MB, 100% in both groups. CONCLUSION: significant statistical difference occurred in breathing modus comparison, negatively affecting some aspects of mouth breathing's mastication, which were mastication time, residue of food in the oral cavity, lips posture and noise during mastication