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The Swift X-ray Telescope (XRT) has discovered that flares are quite common in early X-ray afterglows of gamma-ray bursts (GRBs), being observed in roughly 50% of afterglows with prompt follow-up observations. The flares range in fluence from a few per cent to approximately 100% of the fluence of the prompt emission (the GRB). Repetitive flares are seen, with more than four successive flares detected by the XRT in some afterglows. The rise and fall times of the flares are typically considerably smaller than the time since the burst. These characteristics suggest that the flares are related to the prompt emission mechanism, but at lower photon energies. We conclude that the most likely cause of these flares is late-time activity of the GRB central engine. [ABSTRACT FROM AUTHOR]

This article reports on speech-language pathologists' (SLPs') knowledge related to myths about spoken language learning of children who are deaf and hard of hearing (DHH). The broader study was designed as a step toward narrowing the research-practice gap and providing effective, evidence-based language services to children. In the broader study, SLPs (n = 106) reported their agreement/disagreement with myth statements and true statements (n = 52) about 7 clinical topics related to speech and language development. For the current report, participant responses to 7 statements within the DHH topic were analyzed. Participants exhibited a relative strength in bilingualism knowledge for spoken languages and a relative weakness in audiovisual integration knowledge. Much individual variation was observed. Participants' responses were more likely to align with current evidence about bilingualism if the participants had less experience as an SLP. The findings provide guidance on prioritizing topics for speech-language pathology preservice and professional development., (© The Author(s) 2023. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Purpose: The purpose of this exploratory study was to evaluate speech-language pathologists' (SLPs') conceptions and misconceptions about dyslexia., Method: Participants were 86 school-based SLPs. They completed an online survey on which they rated their agreement and disagreement with true and false statements related to the scientific evidence about the nature of dyslexia and interventions for dyslexia, as well as common misconceptions about dyslexia., Results: There was considerable variability among SLPs' agreement and disagreement with the statements. Critically, despite abundant contrary evidence in the literature, many SLPs believe that dyslexia involves a visual processing deficit., Conclusions: These findings suggest that many school-based SLPs hold misconceptions about dyslexia, especially those related to dyslexia being a visual disorder. The identified misconceptions may contribute to some SLPs' reluctance to incorporate reading and prereading skills into speech-language assessment and intervention. SLPs need greater knowledge of dyslexia to provide more effective evaluations and intervention services.

Purpose: We explore the extent to which speech-language pathologists (SLPs) are operating under assumptions about speech, language, and literacy that are not supported by evidence or are contradicted by evidence., Method: SLPs ( N = 106) marked the degree to which they endorsed or rejected four true and 11 myth (i.e., false) statements on a visual analog scale via an online survey. We analyzed the degree to which participants agreed or disagreed with these statements related to speech, language, and literacy development and impairment., Results: Based on results of one-sample t tests, participants as a group correctly rejected seven myth statements and correctly endorsed three true statements. Participants as a group provided equivocal responses to the remaining four myth statements and one true statement. Scores for each statement spanned all or nearly all of the possible range. Even when participants overall showed relatively strong disagreement with a particular myth statement, at least a few participants endorsed the myth statement., Conclusions: The findings indicate areas of relative strength for SLPs' knowledge of current evidence for augmentative and alternative communication, bilingualism, and language input that supports language development. Identified areas of relative weakness include knowledge of the expected grammatical and speech production skills of children with typical development and the influence of ear infections in childhood on language impairment. Additional research is needed to evaluate efforts to enhance SLPs' knowledge and use of evidence-based practices.

Purpose The purpose of this study was to create and evaluate online learning modules designed to teach speech-language pathologists (SLPs) dialogic reading strategies and phonemic awareness skills. Method School-based SLPs ( n = 28) were assigned to complete one of two online learning modules. One module taught dialogic reading strategies, and the other taught phonemic awareness. Participants in the dialogic reading group served as controls for the phonemic awareness group and vice versa. Participants completed a pretest that assessed phonemic awareness skill and knowledge of dialogic reading strategies to control for prior knowledge and skill, completed their assigned module, and then completed a posttest that assessed phonemic awareness skill and knowledge of dialogic reading strategies. Results Data were analyzed using multiple regression. The independent variables were pretest score, group, and the pretest score by group interaction. The dependent variable in the first model was posttest score on the dialogic reading measure. The dependent variable in the second model was posttest score on the phonemic awareness measure. There was a statistically significant group by posttest score interaction in the dialogic reading model, indicating that the dialogic reading module was effective for improving knowledge of dialogic reading strategies. There was not a statistically significant group by posttest score interaction in the phonemic awareness module, indicating that the phonemic awareness module was not effective for improving phoneme segmentation skill and phoneme manipulation skill. Conclusions Online learning modules may be effective for establishing knowledge needed for evidence-based practice in speech-language pathology. Additional research is warranted to determine whether online learning modules can be used to change clinician intervention behavior.

Soft γ-ray repeaters exhibit bursting emission in hard X-rays and soft γ-rays. During the active phase, they emit random short (milliseconds to several seconds long), hard-X-ray bursts, with peak luminosities 1 of 10 36 to 10 43 erg per second. Occasionally, a giant flare with an energy of around 10 44 to 10 46 erg is emitted 2 . These phenomena are thought to arise from neutron stars with extremely high magnetic fields (10 14 to 10 15 gauss), called magnetars 1,3,4 . A portion of the second-long initial pulse of a giant flare in some respects mimics short γ-ray bursts 5,6 , which have recently been identified as resulting from the merger of two neutron stars accompanied by gravitational-wave emission 7 . Two γ-ray bursts, GRB 051103 and GRB 070201, have been associated with giant flares 2,8-11 . Here we report observations of the γ-ray burst GRB 200415A, which we localized to a 20-square-arcmin region of the starburst galaxy NGC 253, located about 3.5 million parsecs away. The burst had a sharp, millisecond-scale hard spectrum in the initial pulse, which was followed by steady fading and softening over 0.2 seconds. The energy released (roughly 1.3 × 10 46 erg) is similar to that of the superflare 5,12,13 from the Galactic soft γ-ray repeater SGR 1806-20 (roughly 2.3 × 10 46 erg). We argue that GRB 200415A is a giant flare from a magnetar in NGC 253.

Purpose The purpose of this study was to characterize the lexical-morphological networks of children with specific language impairment (SLI) compared to children with typical language by analyzing responses on a morphological derived form production task. Method School-age children with SLI ( n = 32) and peers with typical language ( n = 40) completed an oral cloze derived form production task (Carlisle, 2000). On this task, children were expected to complete verbally presented sentences with a derived form of a provided morphological stem. Responses were coded as correct or incorrect following Carlisle's (2000) stated correct responses. Incorrect responses were coded as scorable or unscorable, and then scorable responses were coded as pseudowords or real words. Real words were further coded according to whether they were repetitions of the given stem. Results There was a statistically significant between-group difference for mean correct responses ( d = 1.43). The scorable incorrect responses of children with SLI included a lower mean proportion of pseudowords than did the incorrect responses of children with typical language ( d = 0.76). Conclusion Because children with SLI produced a lower proportion of pseudowords as scorable incorrect responses than peers with typical language, we conclude that they have less developed lexical-morphological networks and, thus, less derivational morphology knowledge than peers with typical language.

Purpose: The purpose of this study was to evaluate, over 2 separate school years, the school-district-wide failure rate of kindergartners on a screener of grammatical tense marking-the Rice Wexler Test of Early Grammatical Impairment (TEGI) Screening Test (Rice & Wexler, 2001)-composed of past tense (PT) and third-person singular (3S) probes., Method: In the fall of 2 consecutive school years, consented and eligible kindergartners (n = 148 in Year 1, n = 126 in Year 2) in a rural southern school district were administered the TEGI Screening Test. Children who failed the screening test or either of the individual probes (PT or 3S) were administered the Primary Test of Nonverbal Intelligence. All children also completed the Test of Articulation Performance-Screen (Bryant & Bryant, 1983) and, in Year 2, the Get Ready to Read! emergent literacy screener (Whitehurst & Lonigan, 2001)., Results: The screening tool outcome most closely and consistently aligned with the recommended failure rate of approximately 30% (Oetting, Gregory, & Rivière, 2016; based on Tomblin et al., 1997) was the TEGI PT probe. TEGI Screening Test and 3S probe failure rates fell below the recommended level. Most children who failed the PT probe demonstrated nonverbal intelligence skills within the average range. In addition, most children who failed the PT probe would not have been readily identified on the basis of only the results of their articulation or emergent literacy screenings., Conclusions: The TEGI PT probe is an efficient and reliable screener that identifies children for monitoring or additional language assessment. Children with language vulnerabilities are not necessarily identified by articulation or emergent literacy screenings at entry to kindergarten. To identify children at risk for language impairment, it is therefore necessary to directly screen oral language.

Purpose: The purpose of this preliminary study was to (a) compare the pattern of reading subtypes among a clinical sample of children with specific language impairment (SLI) and children with typical language and (b) evaluate phonological and nonphonological language deficits within each reading impairment subtype., Method: Participants were 32 children with SLI and 39 children with typical language in Grades 2 through 4. Each child was classified as demonstrating 1 of 4 reading subtypes on the basis of word-level and text-level skills: typical reading, dyslexia, specific reading comprehension impairment, or garden variety reading impairment. In addition, phonological and nonphonological language skills were evaluated., Results: Children with SLI were more likely to exhibit reading impairments than children with typical language. Children with SLI were more likely to exhibit text-level deficits than children with typical language. Phonological language deficits were observed in children with word-level deficits, and nonphonological language deficits were observed in children with text-level deficits., Conclusions: The results indicate that the patterns of reading subtypes differ among children with SLI and children with typical language. The findings highlight the importance of simultaneously but separately considering word-level and text-level skills in studies of reading impairment.

The purpose of this study was to examine the utility of the Spelling Sensitivity Score (SSS) beyond percentage correct scoring in analysing the spellings of children with specific language impairment (SLI). Participants were 31 children with SLI and 28 children with typical language in grades 2 through 4. Spellings of individual words were scored using two methods: (a) percentage correct and (b) SSS. Children with SLI scored lower than children with typical language when spelling was analysed with percentage correct scoring and with SSS scoring. Additionally, SSS scoring highlighted group differences in the nature of spelling errors. Children with SLI were more likely than children with typical language to omit elements and to represent elements with an illegal grapheme in words, whereas children with typical language were more likely than children with SLI to represent all elements with correct letters.

Long γ-ray bursts (GRBs) are the most dramatic examples of massive stellar deaths, often associated with supernovae. They release ultra-relativistic jets, which produce non-thermal emission through synchrotron radiation as they interact with the surrounding medium. Here we report observations of the unusual GRB 101225A. Its γ-ray emission was exceptionally long-lived and was followed by a bright X-ray transient with a hot thermal component and an unusual optical counterpart. During the first 10 days, the optical emission evolved as an expanding, cooling black body, after which an additional component, consistent with a faint supernova, emerged. We estimate its redshift to be z = 0.33 by fitting the spectral-energy distribution and light curve of the optical emission with a GRB-supernova template. Deep optical observations may have revealed a faint, unresolved host galaxy. Our proposed progenitor is a merger of a helium star with a neutron star that underwent a common envelope phase, expelling its hydrogen envelope. The resulting explosion created a GRB-like jet which became thermalized by interacting with the dense, previously ejected material, thus creating the observed black body, until finally the emission from the supernova dominated. An alternative explanation is a minor body falling onto a neutron star in the Galaxy.

The Swift X-ray Telescope (XRT) has discovered that flares are quite common in early X-ray afterglows of gamma-ray bursts (GRBs), being observed in roughly 50% of afterglows with prompt follow-up observations. The flares range in fluence from a few per cent to approximately 100% of the fluence of the prompt emission (the GRB). Repetitive flares are seen, with more than four successive flares detected by the XRT in some afterglows. The rise and fall times of the flares are typically considerably smaller than the time since the burst. These characteristics suggest that the flares are related to the prompt emission mechanism, but at lower photon energies. We conclude that the most likely cause of these flares is late-time activity of the GRB central engine.

Although the link between long gamma-ray bursts (GRBs) and supernovae has been established, hitherto there have been no observations of the beginning of a supernova explosion and its intimate link to a GRB. In particular, we do not know how the jet that defines a gamma-ray burst emerges from the star's surface, nor how a GRB progenitor explodes. Here we report observations of the relatively nearby GRB 060218 (ref. 5) and its connection to supernova SN 2006aj (ref. 6). In addition to the classical non-thermal emission, GRB 060218 shows a thermal component in its X-ray spectrum, which cools and shifts into the optical/ultraviolet band as time passes. We interpret these features as arising from the break-out of a shock wave driven by a mildly relativistic shell into the dense wind surrounding the progenitor. We have caught a supernova in the act of exploding, directly observing the shock break-out, which indicates that the GRB progenitor was a Wolf-Rayet star.

Gamma-ray burst (GRB) afterglows have provided important clues to the nature of these massive explosive events, providing direct information on the nearby environment and indirect information on the central engine that powers the burst. We report the discovery of two bright x-ray flares in GRB afterglows, including a giant flare comparable in total energy to the burst itself, each peaking minutes after the burst. These strong, rapid x-ray flares imply that the central engines of the bursts have long periods of activity, with strong internal shocks continuing for hundreds of seconds after the gamma-ray emission has ended.

'Long' gamma-ray bursts (GRBs) are commonly accepted to originate in the explosion of particularly massive stars, which give rise to highly relativistic jets. Inhomogeneities in the expanding flow result in internal shock waves that are believed to produce the gamma-rays we see. As the jet travels further outward into the surrounding circumstellar medium, 'external' shocks create the afterglow emission seen in the X-ray, optical and radio bands. Here we report observations of the early phases of the X-ray emission of five GRBs. Their X-ray light curves are characterised by a surprisingly rapid fall-off for the first few hundred seconds, followed by a less rapid decline lasting several hours. This steep decline, together with detailed spectral properties of two particular bursts, shows that violent shock interactions take place in the early jet outflows.

Two classes of rotating neutron stars-soft gamma-ray repeaters (SGRs) and anomalous X-ray pulsars-are magnetars, whose X-ray emission is powered by a very strong magnetic field (B approximately 10(15) G). SGRs occasionally become 'active', producing many short X-ray bursts. Extremely rarely, an SGR emits a giant flare with a total energy about a thousand times higher than in a typical burst. Here we report that SGR 1806-20 emitted a giant flare on 27 December 2004. The total (isotropic) flare energy is 2 x 10(46) erg, which is about a hundred times higher than the other two previously observed giant flares. The energy release probably occurred during a catastrophic reconfiguration of the neutron star's magnetic field. If the event had occurred at a larger distance, but within 40 megaparsecs, it would have resembled a short, hard gamma-ray burst, suggesting that flares from extragalactic SGRs may form a subclass of such bursts.

The International Focusing Optics Collaboration for microCrab Sensitivity (InFOCmicroS) balloonborne hard x-ray telescope incorporates graded Pt/C multilayers replicated onto segmented Al foils to obtain the significant effective area at energies previously inaccessible to x-ray optics. Reflectivity measurements of individual foils demonstrate our capability to produce a mass quantity of multilayered foils with a rms roughness of 0.5 nm. The effective area of the completed mirror is 78 and 22 cm2 at 20 and 40 keV, respectively. The measured half-power diameter is 2.0 +/- 0.6 are min (90% confidence). The successful completion of this mirror demonstrates its applicability to future x-ray telescopes such as Constellation-X.