123 research outputs found
Responses of Neomegalotomus parvus (Hemiptera: Alydidae) to color and male-lured traps
Antifeedant activity of Melia azedarach (L.) extracts to Diabrotica speciosa (Genn.)(Coleoptera: Chrysomelidae) beetles
Morphology of olfactory sensilla and its role in host plant recognition by Neomegalotomus parvus (Westwood) (Heteroptera: Alydidae)
AGILE gamma-ray detection of the exceptional GRB 221009A
Gamma-ray emission in the MeV-GeV range from explosive cosmic events is of
invaluable relevance to understanding physical processes related to the
formation of neutron stars and black holes. Here we report on the detection by
the AGILE satellite in the MeV-GeV energy range of the remarkable long-duration
gamma-ray burst GRB 221009A. The AGILE onboard detectors have good exposure to
GRB 221009A during its initial crucial phases. Hard X-ray/MeV emission in the
prompt phase lasted hundreds of seconds, with the brightest radiation being
emitted between 200 and 300 seconds after the initial trigger. Very intense GeV
gamma-ray emission is detected by AGILE in the prompt and early afterglow phase
up to 10,000 seconds. Time-resolved spectral analysis shows time-variable
MeV-peaked emission simultaneous with intense power-law GeV radiation that
persists in the afterglow phase. The coexistence during the prompt phase of
very intense MeV emission together with highly non-thermal and hardening GeV
radiation is a remarkable feature of GRB 221009A. During the prompt phase, the
event shows spectrally different MeV and GeV emissions that are most likely
generated by physical mechanisms occurring in different locations. AGILE
observations provide crucial flux and spectral gamma-ray information regarding
the early phases of GRB 221009A during which emission in the TeV range was
reported.Comment: Accepted for publication in ApJL on September 19, 202
An X-Ray Burst from a Magnetar Enlightening the Mechanism of Fast Radio Bursts
Fast radio bursts (FRBs) are short (millisecond) radio pulses originating
from enigmatic sources at extragalactic distances so far lacking a detection in
other energy bands. Magnetized neutron stars (magnetars) have been considered
as the sources powering the FRBs, but the connection is controversial because
of differing energetics and the lack of radio and X-ray detections with similar
characteristics in the two classes. We report here the detection by the AGILE
satellite on April 28, 2020 of an X-ray burst in coincidence with the very
bright radio burst from the Galactic magnetar SGR 1935+2154. The burst detected
by AGILE in the hard X-ray band (18-60 keV) lasts about 0.5 seconds, it is
spectrally cutoff above 80 keV, and implies an isotropically emitted energy ~
erg. This event is remarkable in many ways: it shows for the first
time that a magnetar can produce X-ray bursts in coincidence with FRB-like
radio bursts; it also suggests that FRBs associated with magnetars may emit
X-ray bursts of both magnetospheric and radio-pulse types that may be
discovered in nearby sources. Guided by this detection, we discuss SGR
1935+2154 in the context of FRBs, and especially focus on the class of
repeating-FRBs. Based on energetics, magnetars with fields B ~ G may
power the majority of repeating-FRBs. Nearby repeating-FRBs offer a unique
occasion to consolidate the FRB-magnetar connection, and we present new data on
the X-ray monitoring of nearby FRBs. Our detection enlightens and constrains
the physical process leading to FRBs: contrary to previous expectations,
high-brightness temperature radio emission coexists with spectrally-cutoff
X-ray radiation.Comment: Submitted to Nature Astronomy, May 18, 202
Experience of spouses of women with breast cancer: an integrative literature review
Objective: To gather, to characterize, to analyze, to synthesize and to integrate primary studies that addressed the experiences of spouses / husbands / partners of women with breast cancer, presenting the current state of knowledge. Method: Integrative literature review carried out in the databases of VHL, PubMed, CINHAL e SciELO. Results: The sample consisted of eight studies published between 2000-2012, which pointed to the experiences of the involvement and the care of the husbands towards their ill wives. Conclusion: This study highlights the need for attention and assistance to those spouses, as well as guidance and education to exercise the care the same way as the health staff has done with women. Furthermore, it emphasizes the importance of further studies in order to deepen the knowledge on this topic, and thus, improve the care with better scientific basis
Observation of inverse Compton emission from a long γ-ray burst.
Long-duration γ-ray bursts (GRBs) originate from ultra-relativistic jets launched from the collapsing cores of dying massive stars. They are characterized by an initial phase of bright and highly variable radiation in the kiloelectronvolt-to-megaelectronvolt band, which is probably produced within the jet and lasts from milliseconds to minutes, known as the prompt emission1,2. Subsequently, the interaction of the jet with the surrounding medium generates shock waves that are responsible for the afterglow emission, which lasts from days to months and occurs over a broad energy range from the radio to the gigaelectronvolt bands1-6. The afterglow emission is generally well explained as synchrotron radiation emitted by electrons accelerated by the external shock7-9. Recently, intense long-lasting emission between 0.2 and 1 teraelectronvolts was observed from GRB 190114C10,11. Here we report multi-frequency observations of GRB 190114C, and study the evolution in time of the GRB emission across 17 orders of magnitude in energy, from 5 × 10-6 to 1012 electronvolts. We find that the broadband spectral energy distribution is double-peaked, with the teraelectronvolt emission constituting a distinct spectral component with power comparable to the synchrotron component. This component is associated with the afterglow and is satisfactorily explained by inverse Compton up-scattering of synchrotron photons by high-energy electrons. We find that the conditions required to account for the observed teraelectronvolt component are typical for GRBs, supporting the possibility that inverse Compton emission is commonly produced in GRBs
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