We revisit in this work a model for repeating Fast Radio Bursts based of the release of energy provoked by the magnetic field dynamics affecting a magnetar’s crust.We address the basics of such a model by solving the...We revisit in this work a model for repeating Fast Radio Bursts based of the release of energy provoked by the magnetic field dynamics affecting a magnetar’s crust.We address the basics of such a model by solving the propagation of the perturbation approximately,and quantify the energetics and the radiation by bunches of charges in the so-called charge starved region in the magnetosphere.The(almost)simultaneous emission of newly detected X-rays from SGR 1935+2154 is tentatively associated with a reconnection behind the propagation.The strength of f-mode gravitational radiation excited by the event is quantified,and more detailed studies of the nonlinear(spiky)soliton solutions are suggested.展开更多
Over the past few decades, there has been a significant increase in the number of mycobacterial species described. Currently, the genus?Mycobacterium?consists of 170 species. Most species are called nontuberculous myc...Over the past few decades, there has been a significant increase in the number of mycobacterial species described. Currently, the genus?Mycobacterium?consists of 170 species. Most species are called nontuberculous mycobacteria (NTM) and are potentially or rarely pathogenic and ubiquitous. One of the main challenges in mycobacteriology is the rapid and precise identification of these microorganisms. In this work, we compared two protein extraction protocols for the identification of 38 reference strains and clinical isolates, representing 27 species, by mass spectrometry (MALDI-TOF MS) to subsequently use the best method for identifying environmental mycobacteria. The results obtained with reference strains and clinical isolates showed that protocol A was effective in identifying 92.1% of mycobacterial specimens at the species level and protocol B, 50%. Therefore, protocol A was evaluated for the rapid identification of 27 environmental mycobacterial isolates. These isolates were subjected to PCR-restriction enzyme analysis (PRA-hsp65). Two isolates were misidentified by PRA-hsp65, whereas MALDI-TOF MS was able to identify them correctly. The results were confirmed by?hsp65 and 16S rRNA gene sequencing. Mass spectrometry has the advantage of being a simpler and faster technique than PRA-hsp65, and our results showed that MALDI-TOF MS is a valuable tool for the identification of environmental mycobacterial isolates.展开更多
The long-standing problem of the maximum mass that can be achieved by the compact objects,with clear implications for the equation of state of matter above the nuclear saturation density(see ref.[1]and references ther...The long-standing problem of the maximum mass that can be achieved by the compact objects,with clear implications for the equation of state of matter above the nuclear saturation density(see ref.[1]and references therein),is receiving a new twist with the latest data from binary systems and NS-NS merging events.Long ago,double neutron stars systems(DNS)data installed the idea of a"canonical"mass of^1.4 M_⊙,but later work provided evidence for heavier objects with increasing degree of confidence,and it became clear that at least a second"mass scale"had to be present[2].展开更多
基金financial support.J.E.H.has been supported by the CNPq Agency(Brazil)the FAPESP foundation(S?o Paulo,Brazil)。
文摘We revisit in this work a model for repeating Fast Radio Bursts based of the release of energy provoked by the magnetic field dynamics affecting a magnetar’s crust.We address the basics of such a model by solving the propagation of the perturbation approximately,and quantify the energetics and the radiation by bunches of charges in the so-called charge starved region in the magnetosphere.The(almost)simultaneous emission of newly detected X-rays from SGR 1935+2154 is tentatively associated with a reconnection behind the propagation.The strength of f-mode gravitational radiation excited by the event is quantified,and more detailed studies of the nonlinear(spiky)soliton solutions are suggested.
文摘Over the past few decades, there has been a significant increase in the number of mycobacterial species described. Currently, the genus?Mycobacterium?consists of 170 species. Most species are called nontuberculous mycobacteria (NTM) and are potentially or rarely pathogenic and ubiquitous. One of the main challenges in mycobacteriology is the rapid and precise identification of these microorganisms. In this work, we compared two protein extraction protocols for the identification of 38 reference strains and clinical isolates, representing 27 species, by mass spectrometry (MALDI-TOF MS) to subsequently use the best method for identifying environmental mycobacteria. The results obtained with reference strains and clinical isolates showed that protocol A was effective in identifying 92.1% of mycobacterial specimens at the species level and protocol B, 50%. Therefore, protocol A was evaluated for the rapid identification of 27 environmental mycobacterial isolates. These isolates were subjected to PCR-restriction enzyme analysis (PRA-hsp65). Two isolates were misidentified by PRA-hsp65, whereas MALDI-TOF MS was able to identify them correctly. The results were confirmed by?hsp65 and 16S rRNA gene sequencing. Mass spectrometry has the advantage of being a simpler and faster technique than PRA-hsp65, and our results showed that MALDI-TOF MS is a valuable tool for the identification of environmental mycobacterial isolates.
文摘The long-standing problem of the maximum mass that can be achieved by the compact objects,with clear implications for the equation of state of matter above the nuclear saturation density(see ref.[1]and references therein),is receiving a new twist with the latest data from binary systems and NS-NS merging events.Long ago,double neutron stars systems(DNS)data installed the idea of a"canonical"mass of^1.4 M_⊙,but later work provided evidence for heavier objects with increasing degree of confidence,and it became clear that at least a second"mass scale"had to be present[2].
