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IntroductionMost studies of solid organ transplant (SOT) recipients with COVID-19 focus on outcomes within one month of illness onset. Delayed mortality in SOT recipients hospitalized for COVID-19 has not been fully examined.MethodsWe used data from a multicenter registry to calculate mortality by 90 days following initial SARS-CoV-2 detection in SOT recipients hospitalized for COVID-19 and developed multivariable Cox proportional-hazards models to compare risk factors for death by days 28 and 90.ResultsVital status at day 90 was available for 936 of 1117 (84%) SOT recipients hospitalized for COVID-19: 190 of 936 (20%) died by 28 days and an additional 56 of 246 deaths (23%) occurred between days 29 and 90. Factors associated with mortality by day 90 included: age > 65 years [aHR 1.8 (1.3-2.4), p =20% of deaths occurred between 28 and 90 days following SARS-CoV-2 diagnosis. Future investigations should consider extending follow-up duration to 90 days for more complete mortality assessment.

Mortality among patients hospitalized for COVID-19 has declined over the course of the pandemic. Mortality trends specifically in solid organ transplant recipients (SOTR) are unknown. Using data from a multicenter registry of SOTR hospitalized for COVID-19, we compared 28-day mortality between early 2020 (March 1, 2020-June 19, 2020) and late 2020 (June 20, 2020-December 31, 2020). Multivariable logistic regression was used to assess comorbidity-adjusted mortality. Time period of diagnosis was available for 1435/1616 (88.8%) SOTR and 971/1435 (67.7%) were hospitalized: 571/753 (75.8%) in early 2020 and 402/682 (58.9%) in late 2020 (p

Adults can rapidly learn new first-order phonotactic constraints like /f/ only occurs at the beginning of syllables, by producing strings of nonsense syllables such as "hes feng neg kem". The learning is measured by observing their speech errors, e.g., whether /f/’s then always slip to syllable onset position. Context-dependent (second-order) constraints such as /f/ occurs at the beginning of syllables if the vowel is /æ/, but occurs at the end of syllables if the vowel is /ı/ can be learned as well, but errors only follow these constraints after a period of sleep. It has been suggested that the knowledge of newly-learned second-order constraints is isolated from English knowledge in a separate "mini-grammar" and that the creation of the mini�grammar requires a period of sleep. The present study investigates the mini-grammar notion in the learning of first-order constraints, which are learned quickly in a single session. We interleaved trials in which participants produced strings of nonsense syllables with trials in which they repeated English sentences. The English sentences and nonsense sequences either showed the same consonant-position constraints or the opposite constraints. Speech error data showed that the English sentences interfered with the learning of the first-order constraints within the nonsense sequences, suggesting that the constraints in the nonsense context were not separated from ordinary English in a mini-grammar. We hypothesize that the formation of mini-grammars may require consolidation and that no mini�grammar is created for first-order constraint learning.

BackgroundThe coronavirus disease 2019 (COVID-19) pandemic has led to significant reductions in transplantation, motivated in part by concerns of disproportionately more severe disease among solid organ transplant (SOT) recipients. However, clinical features, outcomes, and predictors of mortality in SOT recipients are not well described.MethodsWe performed a multicenter cohort study of SOT recipients with laboratory-confirmed COVID-19. Data were collected using standardized intake and 28-day follow-up electronic case report forms. Multivariable logistic regression was used to identify risk factors for the primary endpoint, 28-day mortality, among hospitalized patients.ResultsFour hundred eighty-two SOT recipients from >50 transplant centers were included: 318 (66%) kidney or kidney/pancreas, 73 (15.1%) liver, 57 (11.8%) heart, and 30 (6.2%) lung. Median age was 58 (interquartile range [IQR] 46-57), median time post-transplant was 5 years (IQR 2-10), 61% were male, and 92% had ≥1 underlying comorbidity. Among those hospitalized (376 [78%]), 117 (31%) required mechanical ventilation, and 77 (20.5%) died by 28 days after diagnosis. Specific underlying comorbidities (age >65 [adjusted odds ratio [aOR] 3.0, 95% confidence interval [CI] 1.7-5.5, P

Lung transplant recipients (LTR) with coronavirus disease 2019 (COVID-19) may have higher mortality than non-lung solid organ transplant recipients (SOTR), but direct comparisons are limited. Risk factors for mortality specifically in LTR have not been explored. We performed a multicenter cohort study of adult SOTR with COVID-19 to compare mortality by 28 days between hospitalized LTR and non-lung SOTR. Multivariable logistic regression models were used to assess comorbidity-adjusted mortality among LTR vs. non-lung SOTR and to determine risk factors for death in LTR. Of 1,616 SOTR with COVID-19, 1,081 (66%) were hospitalized including 120/159 (75%) LTR and 961/1457 (66%) non-lung SOTR (p = .02). Mortality was higher among LTR compared to non-lung SOTR (24% vs. 16%, respectively, p = .032), and lung transplant was independently associated with death after adjusting for age and comorbidities (aOR 1.7, 95% CI 1.0-2.6, p = .04). Among LTR, chronic lung allograft dysfunction (aOR 3.3, 95% CI 1.0-11.3, p = .05) was the only independent risk factor for mortality and age >65 years, heart failure and obesity were not independently associated with death. Among SOTR hospitalized for COVID-19, LTR had higher mortality than non-lung SOTR. In LTR, chronic allograft dysfunction was independently associated with mortality.

Disfluency in speech leads listeners, even two-year-oldchildren, to expect the speaker to refer to novel and discourse-new objects. Previous evidence suggests this link betweendisfluency and discourse novelty is not driven simply bytracking of co-occurrence statistics connecting disfluency withreference to a new object, but also by integrating extra-linguistic information about the speaker’s perspective. Weasked whether children can attribute a speaker’s disfluency todifferent sources – language planning difficulty vs. distractionfrom the conversation. We tested children’s processing ofdisfluency when interacting with an engaged versus adistracted speaker. When the engaged speaker was disfluent,children looked more at a novel and discourse-new image thanat a familiar and just-named image, consistent with the existingliterature. This disfluency effect was attenuated when thespeaker was distracted, suggesting that four-year-old childrencan flexibly attribute a speaker’s disfluency to different sourcesin online interpretation of disfluent speech.

Children use syntax to learn verbs, in a process known as syntactic bootstrapping. The structure-mapping account proposes that syntactic bootstrapping begins with a universal bias to map each noun phrase in a sentence onto a participant role in a structured conceptual representation of an event. Equipped with this bias, children interpret the number of noun phrases accompanying a new verb as evidence about the semantic predicate-argument structure of the sentence, and therefore about the meaning of the verb. In this paper, we first review evidence for the structure-mapping account, and then discuss challenges to the account arising from the existence of languages that allow verbs' arguments to be omitted, such as Korean. These challenges prompt us to (a) refine our notion of the distributional learning mechanisms that create representations of sentence structure, and (b) propose that an expectation of discourse continuity allows children to gather linguistic evidence for each verb's arguments across sentences in a coherent discourse. Taken together, the proposed learning mechanisms and biases sketch a route whereby simple aspects of sentence structure guide verb learning from the start of multi-word sentence comprehension, and do so even if some of the new verb's arguments are omitted due to discourse redundancy.

Background: Better access to direct‐acting antiviral (DAA) therapy has broadened the utilization of hepatitis C virus (HCV) nucleic acid testing (NAT) positive organs with excellent outcomes. However, DAA therapy has been associated with hepatitis B virus (HBV) reactivation. Aim: To determine the risk of HBV transmission or reactivation with utilization of HBV core antibody positive (HBcAb+) and HCV NAT positive (HCV+) organs, which presumably required DAA therapy. Methods: The number of HBcAb+ donors with delineated HCV NAT status was obtained from the Organ Procurement and Transplantation Network (OPTN) database. The number of unexpected HBV infections from transplanted organs adjudicated as "proven" or "probable" transmission was obtained from the OPTN Ad Hoc Disease Transmission Advisory Committee database. A chart review of the donors of "proven" or "probable" cases was conducted. Results: From January 1, 2016, to December 31, 2021, 7735 organs were procured from 3767 HBcAb+ donors and transplanted into 7469 recipients; 545 (14.5%) donors were also HCV+. HBV transmission or reactivation occurred in seven recipients. The rate is not significantly different between recipients of HCV+ (0.18%, 2/1115) and the HCV NAT negative (HCV‐) organs (0.08%, 5/6354) (p = 0.28) or between recipients of HCV+ and HCV‐ livers as well as non‐liver organs. HBV transmission or reactivation occurred within a median of 319 (range, 41–1117) days post‐transplant in the setting of missing, inadequate, or truncated prophylaxis. Conclusion: HBV reactivation associated with DAA therapy for HBcAb+ HCV+ organs is less frequent than reported in the non‐transplant population, possibly due to the common use of HBV prophylaxis in the at‐risk transplant population. [ABSTRACT FROM AUTHOR]

Chronic lung allograft dysfunction (CLAD) is the most common cause of long-term lung allograft failure. Several factors, including respiratory virus infection (RVI), have been associated with CLAD development, but the underlying mechanisms of these associations are not well understood. We hypothesize that RVI in lung transplant recipients elicits the development of donor-specific antibodies (DSAs), thus providing a mechanistic link between RVI and CLAD development. To test this hypothesis, we retrospectively evaluated for the presence of HLA antibodies in a cohort of lung transplant recipients with symptomatic RVI within the first four months post-transplant using sera at two time points (at/directly after the transplant and following RVI) and time-matched controls without RVI (post-transplant). We found a trend toward the development of de novo DSAs in those with symptomatic RVI versus controls [6/21 (29%) vs. 1/21 (5%), respectively, p = 0.09]. No cases or controls had DSA at baseline. We also found increased rates of CLAD and death among those who developed class II DSA versus those who did not (CLAD: 5/7 (71.4%) vs. 19/34 (54.3%), death: 5/7 (71.4%) vs. 17/35 (48.6%)). Prospective studies evaluating the temporal development of DSA after RVI in lung transplant patients and the subsequent outcomes are warranted. [ABSTRACT FROM AUTHOR]

Classic studies reveal two striking differences between preschoolers and adults in online sentence comprehension. Adults (a) recruit referential context cues to guide syntactic parsing, interpreting an ambiguous phrase as a modifier if a modifier is needed to single out the intended referent among multiple options, and (b) use late-arriving information to recover from misinterpretation. Five-year-olds fail on both counts, appearing insensitive to the referential context and often failing to recover from parsing errors (Trueswell, Sekerina, Hill, & Logrip, 1999). But other findings suggest that 5-year-olds show "delayed" rather than absent sensitivity to the referential context, and that individual differences in executive functioning predict children's ability to recover from garden-path errors. In 2 experiments, we built on these findings, focusing on whether children recruit referential-context cues if given time to do so. Children heard temporarily ambiguous instructions (e.g., "Put the frog on the pond into the tent"), while we monitored their eye-gaze and actions. We used a slow speech rate, and manipulated referential context between rather than within subjects, to give children time to bring referential context cues into play. Across experiments, eye-movement and action analyses revealed emerging sensitivity to the referential context. Moreover, error rates and eye-movement patterns indicating failures to revise were predicted by individual differences in executive function (scores in Simon Says and Flanker tasks). These data suggest that children, like adults, use referential context information in syntactic processing under some circumstances; the findings are also consistent with a role for domain-general executive function in resolution of syntactic ambiguity.

Children and adults are guided by verb-specific syntactic like-lihoods, or verb bias, in language comprehension and produc-tion. Recent reports showed that verb bias can be altered bynew linguistic experience. We investigated the mechanismsunderlying this verb bias learning or adaptation. Specifically,we asked whether verb bias learning, like abstract syntacticpriming, is driven by error-based implicit learning. We reportthree experiments in which we altered the biases of familiardative verbs in children’s and adults’ sentence production, viatraining trials that induced participants to produce each verbconsistently in either double-object or prepositional-object da-tive structures. Participants’ syntactic choices in later test trialsreflected the expected adaptation of verb bias to the trainingexperience. In addition, the magnitude of the training effectvaried with the likelihood of each sentence structure and withpre-existing verb bias: Unexpected verb-structure combina-tions resulted in larger training effects, suggesting the opera-tion of error-based implicit learning.

The Comparison of Antiviral Preventative Strategies In Liver Transplant (CAPSIL) study showed pre‐emptive therapy (PET) to be superior to antiviral prophylaxis for Cytomegalovirus (CMV) disease prevention in high‐risk CMV seronegative liver transplant recipients (LTRs) with seropositive donors (D+R−). Despite the statistical superiority of PET over prophylaxis in research settings, PET is perceived as a logistically more complex strategy that requires careful coordination of weekly CMV PCR testing, prompt initiation of CMV antivirals upon viremia detection, and timely cessation of antivirals following viremia resolution. Transplant centers may be hesitant to use PET for CMV disease prevention in D+R− LTRs out of concern that PET coordination is not feasible in clinical practice. We recently described our experience using PET in CMV D+R− LTRs in a real‐world setting, and found it to be as effective for CMV disease prevention as PET performed as part of a clinical trial. Here, we describe a systematic approach for PET implementation in real‐world settings and provide practical tools to address anticipated challenges. This framework can support transplant programs in overcoming logistical barriers to PET and incorporating an evidence‐based and cost‐effective CMV prevention strategy into routine care for high‐risk CMV D+R− LTRs. [ABSTRACT FROM AUTHOR]

Recent evidence shows that children can use cross-situational statistics to learn new object labels under referential ambiguity (e.g., Smith & Yu, 2008). Such evidence has been interpreted as support for proposals that statistical information about word-referent co-occurrence plays a powerful role in word learning. But object labels represent only a fraction of the vocabulary children acquire, and arguably represent the simplest case of word learning based on observations of world scenes. Here we extended the study of cross-situational word learning to a new segment of the vocabulary, action verbs, to permit a stronger test of the role of statistical information in word learning. In two experiments, on each trial 2.5-year-olds encountered two novel intransitive (e.g., "She's pimming!"; Experiment 1) or transitive verbs (e.g., "She's pimming her toy!"; Experiment 2) while viewing two action events. The consistency with which each verb accompanied each action provided the only source of information about the intended referent of each verb. The 2.5-year-olds used cross-situational consistency in verb learning, but also showed significant limits on their ability to do so as the sentences and scenes became slightly more complex. These findings help to define the role of cross-situational observation in word learning.

In a post-hoc analysis of the association of CMV DNAemia with long-term mortality in a randomized trial of CMV preemptive therapy vs. antiviral prophylaxis in D+R- liver transplant recipients, post-intervention CMV DNAemia was associated with increased mortality after adjusting for study arm. [ABSTRACT FROM AUTHOR]

Background Plasma microbial cell-free DNA sequencing (mcfDNA-Seq) is a noninvasive test for microbial diagnosis of invasive mold infection (IMI). The utility of mcfDNA-Seq for predicting IMI onset and the clinical implications of mcfDNA concentrations are unknown. Methods We retrospectively tested plasma from hematopoietic cell transplant (HCT) recipients with pulmonary IMI and ≥1 mold identified by mcfDNA-Seq in plasma collected within 14 days of clinical diagnosis. Samples collected from up to 4 weeks before and 4 weeks after IMI diagnosis were evaluated using mcfDNA-Seq. Results Thirty-five HCT recipients with 39 IMIs (16 Aspergillus and 23 non- Aspergillus infections) were included. Pathogenic molds were detected in 38%, 26%, 11%, and 0% of samples collected during the first, second, third, and fourth week before clinical diagnosis, respectively. In non- Aspergillus infections, median mcfDNA concentrations in samples collected within 3 days of clinical diagnosis were higher in infections with versus without extrapulmonary spread (4.3 vs 3.3 log10 molecules per microliter [mpm], P =.02), and all patients (8/8) with mcfDNA concentrations >4.0 log10 mpm died within 42 days after clinical diagnosis. Conclusions Plasma mcfDNA-Seq can identify pathogenic molds up to 3 weeks before clinical diagnosis of pulmonary IMI. Plasma mcfDNA concentrations may correlate with extrapulmonary spread and mortality in non- Aspergillus IMI. [ABSTRACT FROM AUTHOR]