Chromospheric impact of an exploding solar granule

Observations of multi-wavelength and therefore height-dependent information following events throughout the solar atmosphere and unambiguously assigning a relation between these rapidly evolving layers are rare and difficult to obtain. Yet, they are crucial for our understanding of the physical processes that couple the different regimes in the solar atmosphere. We characterize the exploding granule event with simultaneous observations of Hinode spectroplarimetric data in the solar photosphere and Hinode broadband CaIIH images combined with Interface Region Imaging Spectrograph (IRIS) slit spectra. We follow the evolution of an exploding granule and its connectivity throughout the atmosphere and analyze the dynamics of a magnetic element that has been affected by the abnormal granule. In addition to magnetic flux maps we use a local correlation tracking method to infer the horizontal velocity flows in the photosphere and apply a wavelet analysis on several IRIS chromospheric emission features such as MgIIk2v and MgIIk3 to detect oscillatory phenomena indicating wave propagation. During the vigorous expansion of the abnormal granule we detect radially outward horizontal flows, causing, together with the horizontal flows from the surrounding granules, the magnetic elements in the bordering intergranular lanes to be squeezed and elongated. In reaction to the squeezing, we detect a chromospheric intensity and velocity oscillation pulse which we identify as an upward traveling hot shock front propagating clearly through the IRIS spectral line diagnostics of MgIIh&k. Conclusion: Exploding granules can trigger upward-propagating shock fronts that dissipate in the chromosphere.Comment: 5 pages (3 figures)+1 page movie snapshots(2 figures), accepted in A&A letters, movies can be found at http://www.science-media.org/216 and http://www.science-media.org/21

Neural Substrate of Concurrent Sound Perception: Direct Electrophysiological Recordings from Human Auditory Cortex

In everyday life, consciously or not, we are constantly disentangling the multiple auditory sources contributing to our acoustical environment. To better understand the neural mechanisms involved in concurrent sound processing, we manipulated sound onset asynchrony to induce the segregation or grouping of two concurrent sounds. Each sound consisted of amplitude-modulated tones at different carrier and modulation frequencies, allowing a cortical tagging of each sound. Electrophysiological recordings were carried out in epileptic patients with pharmacologically resistant partial epilepsy, implanted with depth electrodes in the temporal cortex. Patients were presented with the stimuli while they performed an auditory distracting task. We found that transient and steady-state evoked responses, and induced gamma oscillatory activities were enhanced in the case of onset synchrony. These effects were mainly located in the Heschl's gyrus for steady-state responses whereas they were found in the lateral superior temporal gyrus for evoked transient responses and induced gamma oscillations. They can be related to distinct neural mechanisms such as frequency selectivity and habituation. These results in the auditory cortex provide an anatomically refined description of the neurophysiological components which might be involved in the perception of concurrent sounds

Non-Verbal Auditory Cognition in Patients with Temporal Epilepsy Before and After Anterior Temporal Lobectomy

For patients with pharmaco-resistant temporal epilepsy, unilateral anterior temporal lobectomy (ATL) – i.e. the surgical resection of the hippocampus, the amygdala, the temporal pole and the most anterior part of the temporal gyri – is an efficient treatment. There is growing evidence that anterior regions of the temporal lobe are involved in the integration and short-term memorization of object-related sound properties. However, non-verbal auditory processing in patients with temporal lobe epilepsy (TLE) has raised little attention. To assess non-verbal auditory cognition in patients with temporal epilepsy both before and after unilateral ATL, we developed a set of non-verbal auditory tests, including environmental sounds. We could evaluate auditory semantic identification, acoustic and object-related short-term memory, and sound extraction from a sound mixture. The performances of 26 TLE patients before and/or after ATL were compared to those of 18 healthy subjects. Patients before and after ATL were found to present with similar deficits in pitch retention, and in identification and short-term memorisation of environmental sounds, whereas not being impaired in basic acoustic processing compared to healthy subjects. It is most likely that the deficits observed before and after ATL are related to epileptic neuropathological processes. Therefore, in patients with drug-resistant TLE, ATL seems to significantly improve seizure control without producing additional auditory deficits

JPEG2000 image compression on solar EUV images

For future solar missions as well as ground-based telescopes, efficient ways to return and process data has become increasingly important. Solar Or-biter, e.g., the next ESA/NASA mission to explore the Sun and the heliosphere,is a deep-space mission, which implies a limited telemetry rate that makes efficient onboard data compression a necessity to achieve the mission science goals.Missions like the Solar Dynamics Observatory (SDO) and future ground-based telescopes such as the Daniel K. Inouye Solar Telescope, on the other hand,face the challenge of making petabyte-sized solar data archives accessible to the solar community. New image compression standards address these challenges by implementing efficient and flexible compression algorithms that can be tailored to user requirements. We analyse solar images from the Atmospheric Imaging Assembly (AIA) instrument onboard SDO to study the effect of lossy JPEG2000(from the Joint Photographic Experts Group 2000) image compression at different bit rates. To assess the quality of compressed images, we use the mean structural similarity (MSSIM) index as well as the widely used peak signal-to noise ratio (PSNR) as metrics and compare the two in the context of solar EUV images. In addition, we perform tests to validate the scientific use of the lossily compressed images by analysing examples of an on-disk and off-limb coronal loop oscillation time series observed by AIA/SDO.PostprintPeer reviewe

A Research Agenda for (Gender) Troubled Times: Striving for a Better Tomorrow

As we gathered on Zoom to begin this editorial, a typical COVID-19 experience unfolded. Working from our living rooms, kitchens, or closets (Eileen) we checked in as to how each of us was coping, knowing that we were navigating multiple responsibilities and uncertainties. Having assured ourselves that we were all “fine, really, okay,” we proceeded to get down to work, only to have Linda’s kids start vying for her attention because—of course—she’s not just trying to write an editorial, she’s also overseeing the online learning they are supposed to be doing. If we needed it, our shared experience was living proof of how the pandemic has impacted all of our—inevitably gendered—lives. All of us are trying to share our spaces with family members who are attempting to accomplish things in homes that were not designed for the purposes for which they are being tasked. And one of us is trying to do her work at the same time she’s overseeing the care, feeding, and education of two kids. Little did we imagine when we crafted our call for articles for this special issue the profound disjuncture between “the before times” and our current surreal circumstances. The once taken-for-granted institutions in society—work, school, family, government—have been significantly disrupted due to the pandemic. More than ever, due to both the pandemic and the heightened salience of systemic racism, the problematic facets of existing institutions are now exposed. And the resulting inequities are stark. While research published in this issue was not born out of the context of multiple tumultuous global events, including COVID-19 and the Black Lives Matter social justice movement, we recognize the unique opportunity we have in this editorial to speak to the current moment

CHARACERIZING DRIVER GENE HETEROGENEITY AND CLONAL ORIGIN OF INTRADUCTAL PAPILLARY MUCINOUS NEOPLASMS OF THE PANCREAS

Intraductal papillary mucinous neoplasms (IPMNs) are precancerous lesions that can progress to invasive pancreatic cancer and a key system in which to study early pancreatic tumorigenesis. We used a combination of multi-region and single-cell targeted next generation sequencing to assess the diversity of somatic driver gene mutations in IPMNs. The resulting data, combined with evolutionary modeling, whole exome sequencing, and in situ mutation detection, show that the earliest stages of pancreatic tumorigenesis are characterized by independent clones with distinct early driver gene mutations, thus revealing the polyclonal origin of precancerous pancreatic neoplasms. In addition, multiple mutations in later-occurring driver genes were also common and were frequently localized to unique tumor clones, raising the possibility of convergent evolution of these genetic events in pancreatic tumorigenesis. Collectively, our data demonstrate substantial genetic heterogeneity within IPMN, predominately in IPMNs with low-grade dysplasia. These data also challenge traditional monoclonal tumor origin models and transform our understanding of the evolutionary history of pancreatic neoplasia. Understanding the mechanism underlying polyclonal precancers may reveal new strategies to identify patients at increased risk of developing invasive pancreatic cancer

Using the TIDieR checklist to describe health visitor support for mothers with mental health problems: analysis of a cross-sectional survey

At least half of the 20% of mothers who experience mental health problems (MHPs) during pregnancy or after birth are not receiving the help they need that will lead to recovery. In order to identify where improvements need to be made it is necessary to describe exactly what is being done and the barriers and facilitators that compromise or enhance optimal care. The majority of mothers experience mild to moderate anxiety or depression. The expectation is that primary care professionals, such as health visitors (HVs), can provide the support they need that will lead to recovery. The aim of this study was explore the views of HVs regarding the content and purpose of an intervention to support mothers with MHPs, described as ‘listening visits’ (LVs). A link to an on-line survey was offered to the members and champions of the Institute of Health Visiting (n=9,474) March – May 2016. The survey was completed by 1599 (17%) of the target population, of whom 85% were offering LVs. The Template for Intervention Description and Replication (TIDieR) checklist was used to provide a framework to describe commonalities and variations in practice. There appeared to be a shared understanding of the rationale for LVs but a lack of agreement about what the intervention should be called, the techniques that should be used and the duration, frequency and expected outcomes of the intervention. Contextual factors such as staff shortages; conflicting priorities; the needs and circumstances of mothers; the capability and motivation of HVs; inadequate training and supervision; and absence of clear guidance contributed to variations in perceptions and practice. There are many ways in which the HV contribution to the assessment and management of mothers with MHPs could be improved. The intervention delivered by HVs needs to be more clearly articulated. The contextual factors influencing competent and consistent practice also need to be addressed