Orbital period change of Dimorphos due to the DART kinetic impact.

The Double Asteroid Redirection Test (DART) spacecraft successfully performed the first test of a kinetic impactor for asteroid deflection by impacting Dimorphos, the secondary of near-Earth binary asteroid (65803) Didymos, and changing the orbital period of Dimorphos. A change in orbital period of approximately 7 min was expected if the incident momentum from the DART spacecraft was directly transferred to the asteroid target in a perfectly inelastic collision1, but studies of the probable impact conditions and asteroid properties indicated that a considerable momentum enhancement (ß) was possible2,3. In the years before impact, we used lightcurve observations to accurately determine the pre-impact orbit parameters of Dimorphos with respect to Didymos4-6. Here we report the change in the orbital period of Dimorphos as a result of the DART kinetic impact to be -33.0 ± 1.0 (3σ) min. Using new Earth-based lightcurve and radar observations, two independent approaches determined identical values for the change in the orbital period. This large orbit period change suggests that ejecta contributed a substantial amount of momentum to the asteroid beyond what the DART spacecraft carried.

Ejecta from the DART-produced active asteroid Dimorphos.

Some active asteroids have been proposed to be formed as a result of impact events1. Because active asteroids are generally discovered by chance only after their tails have fully formed, the process of how impact ejecta evolve into a tail has, to our knowledge, not been directly observed. The Double Asteroid Redirection Test (DART) mission of NASA2, in addition to having successfully changed the orbital period of Dimorphos3, demonstrated the activation process of an asteroid resulting from an impact under precisely known conditions. Here we report the observations of the DART impact ejecta with the Hubble Space Telescope from impact time T + 15 min to T + 18.5 days at spatial resolutions of around 2.1 km per pixel. Our observations reveal the complex evolution of the ejecta, which are first dominated by the gravitational interaction between the Didymos binary system and the ejected dust and subsequently by solar radiation pressure. The lowest-speed ejecta dispersed through a sustained tail that had a consistent morphology with previously observed asteroid tails thought to be produced by an impact4,5. The evolution of the ejecta after the controlled impact experiment of DART thus provides a framework for understanding the fundamental mechanisms that act on asteroids disrupted by a natural impact1,6.

Successful kinetic impact into an asteroid for planetary defence.

Although no known asteroid poses a threat to Earth for at least the next century, the catalogue of near-Earth asteroids is incomplete for objects whose impacts would produce regional devastation1,2. Several approaches have been proposed to potentially prevent an asteroid impact with Earth by deflecting or disrupting an asteroid1-3. A test of kinetic impact technology was identified as the highest-priority space mission related to asteroid mitigation1. NASA's Double Asteroid Redirection Test (DART) mission is a full-scale test of kinetic impact technology. The mission's target asteroid was Dimorphos, the secondary member of the S-type binary near-Earth asteroid (65803) Didymos. This binary asteroid system was chosen to enable ground-based telescopes to quantify the asteroid deflection caused by the impact of the DART spacecraft4. Although past missions have utilized impactors to investigate the properties of small bodies5,6, those earlier missions were not intended to deflect their targets and did not achieve measurable deflections. Here we report the DART spacecraft's autonomous kinetic impact into Dimorphos and reconstruct the impact event, including the timeline leading to impact, the location and nature of the DART impact site, and the size and shape of Dimorphos. The successful impact of the DART spacecraft with Dimorphos and the resulting change in the orbit of Dimorphos7 demonstrates that kinetic impactor technology is a viable technique to potentially defend Earth if necessary.

Momentum transfer from the DART mission kinetic impact on asteroid Dimorphos.

The NASA Double Asteroid Redirection Test (DART) mission performed a kinetic impact on asteroid Dimorphos, the satellite of the binary asteroid (65803) Didymos, at 23:14 UTC on 26 September 2022 as a planetary defence test1. DART was the first hypervelocity impact experiment on an asteroid at size and velocity scales relevant to planetary defence, intended to validate kinetic impact as a means of asteroid deflection. Here we report a determination of the momentum transferred to an asteroid by kinetic impact. On the basis of the change in the binary orbit period2, we find an instantaneous reduction in Dimorphos's along-track orbital velocity component of 2.70 ± 0.10 mm s-1, indicating enhanced momentum transfer due to recoil from ejecta streams produced by the impact3,4. For a Dimorphos bulk density range of 1,500 to 3,300 kg m-3, we find that the expected value of the momentum enhancement factor, ß, ranges between 2.2 and 4.9, depending on the mass of Dimorphos. If Dimorphos and Didymos are assumed to have equal densities of 2,400 kg m-3, [Formula: see text]. These ß values indicate that substantially more momentum was transferred to Dimorphos from the escaping impact ejecta than was incident with DART. Therefore, the DART kinetic impact was highly effective in deflecting the asteroid Dimorphos.

Benchmarking cell-type clustering methods for spatially resolved transcriptomics data.

Spatially resolved transcriptomics technologies enable the measurement of transcriptome information while retaining the spatial context at the regional, cellular or sub-cellular level. While previous computational methods have relied on gene expression information alone for clustering single-cell populations, more recent methods have begun to leverage spatial location and histology information to improve cell clustering and cell-type identification. In this study, using seven semi-synthetic datasets with real spatial locations, simulated gene expression and histology images as well as ground truth cell-type labels, we evaluate 15 clustering methods based on clustering accuracy, robustness to data variation and input parameters, computational efficiency, and software usability. Our analysis demonstrates that even though incorporating the additional spatial and histology information leads to increased accuracy in some datasets, it does not consistently improve clustering compared with using only gene expression data. Our results indicate that for the clustering of spatial transcriptomics data, there are still opportunities to enhance the overall accuracy and robustness by improving information extraction and feature selection from spatial and histology data.

Influenza Vaccine Effectiveness Pre-pandemic Among Adults Hospitalized With Congestive Heart Failure or Chronic Obstructive Pulmonary Disease and Older Adults.

BACKGROUND: Data are limited on influenza vaccine effectiveness (VE) in the prevention of influenza-related hospitalizations in older adults and those with underlying high-risk comorbidities. METHODS: We conducted a prospective, test-negative, case-control study at 2 US hospitals from October 2018-March 2020 among adults aged ≥50 years hospitalized with acute respiratory illnesses (ARIs) and adults ≥18 years admitted with congestive heart failure (CHF) or chronic obstructive pulmonary disease (COPD) exacerbations. Adults were eligible if they resided in 1 of 8 counties in metropolitan Atlanta, Georgia. Nasopharyngeal and oropharyngeal swabs were tested using BioFire FilmArray (bioMérieux, Inc.) respiratory panel, and standard-of-care molecular results were included when available. Influenza vaccination history was determined from the Georgia vaccine registry and medical records. We used multivariable logistic regression to control for potential confounders and to determine 95% confidence intervals (CIs). RESULTS: Among 3090 eligible adults, 1562 (50.6%) were enrolled. Of the 1515 with influenza vaccination history available, 701 (46.2%) had received vaccination during that season. Influenza was identified in 37 (5.3%) vaccinated versus 78 (9.6%) unvaccinated participants. After adjustment for age, race/ethnicity, immunosuppression, month, and season, pooled VE for any influenza-related hospitalization in the eligible study population was 63.1% (95% CI, 43.8-75.8%). Adjusted VE against influenza-related hospitalization for ARI in adults ≥50 years was 55.9% (29.9-72.3%) and adjusted VE against influenza-related CHF/COPD exacerbation in adults ≥18 years was 80.3% (36.3-93.9%). CONCLUSIONS: Influenza vaccination was effective in preventing influenza-related hospitalizations in adults aged ≥50 years and those with CHF/COPD exacerbations during the 2018-2020 seasons.

Methylene blue dose-dependently induces cutaneous inflammation and heat hyperalgesia in a novel rat model.

Methylene blue (MB) has been shown to reduce mortality and morbidity in vasoplegic patients after cardiac surgery. Though MB is considered to be safe, extravasation of MB leading to cutaneous toxicity has been reported. In this study, we sought to characterize MB-induced cutaneous toxicity and investigate the underlying mechanisms. To induce MB-induced cutaneous toxicity, we injected 64 adult male Sprague-Dawley rates with 200 µL saline (vehicle) or 1%, 0.1%, or 0.01% MB in the plantar hind paws. Paw swelling, skin histologic changes, and heat and mechanical hyperalgesia were measured. Injection of 1%, but not 0.1% or 0.01% MB, produced significant paw swelling compared to saline. Injection of 1% MB produced heat hyperalgesia but not mechanical hyperalgesia. Pain behaviors were unchanged following injections of 0.1% or 0.01% MB. Global transcriptomic analysis by RNAseq identified 117 differentially expressed genes (111 upregulated, 6 downregulated). Ingenuity Pathway Analysis showed an increased quantity of leukocytes, increased lipids, and decreased apoptosis of myeloid cells and phagocytes with activation of IL-1ß and Fos as the two major regulatory hubs. qPCR showed a 16-fold increase in IL-6 mRNA. Thus, using a novel rat model of MB-induced cutaneous toxicity, we show that infiltration of 1% MB into cutaneous tissue causes a dose-dependent pro-inflammatory response, highlighting potential roles of IL-6, IL-1ß, and Fos. Thus, anesthesiologists should administer dilute MB intravenously through peripheral venous catheters. Higher concentrations of MB (1%) should be administered through a central venous catheter to minimize the risk of cutaneous toxicity.

Safety and Efficacy of Efruxifermin in Combination With a GLP-1 Receptor Agonist in Patients With NASH/MASH and Type 2 Diabetes in a Randomized Phase 2 Study.

BACKGROUND & AIMS: In phase 2 studies, efruxifermin, an Fc-FGF21 analog, significantly reduced steatohepatitis and fibrosis in patients with non-alcoholic steatohepatitis, now called metabolic dysfunction-associated steatohepatitis (MASH), for which there is no approved treatment. Type 2 diabetes (T2D) and obesity are prevalent among patients with MASH and increasingly treated with glucagon-like peptide-1 receptor agonists (GLP-1RAs). This study evaluated the safety and efficacy of efruxifermin in patients with MASH, fibrosis, and T2D taking a GLP-1RA. METHODS: Cohort D was a double-blind, placebo-controlled, phase 2b study in adults with T2D and MASH with fibrosis (F1-F3) on stable GLP-1RA therapy randomized (2:1) to receive efruxifermin 50 mg or placebo, once weekly for 12 weeks. The primary endpoint was safety and tolerability of efruxifermin added to a stable dose of GLP-1RA. Secondary endpoints included changes in hepatic fat fraction (HFF), markers of liver injury and fibrosis, and metabolic parameters. RESULTS: Adults (N = 31) with T2D and MASH fibrosis (F1-F3) on a stable GLP-1RA (semaglutide, 48.4%; dulaglutide, 45.2%; liraglutide, 6.5%) received efruxifermin 50 mg (n = 21) or placebo (n = 10) for 12 weeks. The addition of efruxifermin to a GLP-1RA appeared safe and well-tolerated. The most frequent efruxifermin-related adverse events were mild to moderate gastrointestinal events. One patient receiving efruxifermin discontinued due to nausea, and another withdrew consent. There were no treatment-related serious adverse events. After 12 weeks, efruxifermin reduced HFF by 65% (P < .0001 vs placebo) compared with a 10% reduction for placebo (GLP-1RA alone). Efruxifermin also improved noninvasive markers of liver injury, fibrosis, glucose, and lipid metabolism while maintaining GLP-1RA-mediated weight loss. CONCLUSIONS: The tolerability profile of efruxifermin added to GLP-1RA appeared comparable to that of either drug alone, while also significantly reducing HFF and noninvasive markers of fibrosis in patients with MASH and T2D. Liver health in patients already on a GLP-1RA may be further improved by addition of efruxifermin. CLINICALTRIALS: gov, Number: NCT05039450.

Decreased erythrocyte aggregation in Glenn and Fontan: univentricular circulation as a rheologic disease model.

BACKGROUND: In the Fontan palliation for single ventricle heart disease (SVHD), pulmonary blood flow is non-pulsatile/passive, low velocity, and low shear, making viscous power loss a critical determinant of cardiac output. The rheologic properties of blood in SVHD patients are essential for understanding and modulating their limited cardiac output and they have not been systematically studied. We hypothesize that viscosity is decreased in single ventricle circulation. METHODS: We evaluated whole blood viscosity, red blood cell (RBC) aggregation, and RBC deformability to evaluate changes in healthy children and SVHD patients. We altered suspending media to understand cellular and plasma differences contributing to rheologic differences. RESULTS: Whole blood viscosity was similar between SVHD and healthy at their native hematocrits, while viscosity was lower at equivalent hematocrits for SVHD patients. RBC deformability is increased, and RBC aggregation is decreased in SVHD patients. Suspending SVHD RBCs in healthy plasma resulted in increased RBC aggregation and suspending healthy RBCs in SVHD plasma resulted in lower RBC aggregation. CONCLUSIONS: Hematocrit corrected blood viscosity is lower in SVHD vs. healthy due to decreased RBC aggregation and higher RBC deformability, a viscous adaptation of blood in patients whose cardiac output is dependent on minimizing viscous power loss. IMPACT: Patients with single ventricle circulation have decreased red blood cell aggregation and increased red blood cell deformability, both of which result in a decrease in blood viscosity across a large shear rate range. Since the unique Fontan circulation has very low-shear and low velocity flow in the pulmonary arteries, blood viscosity plays an increased role in vascular resistance, therefore this work is the first to describe a novel mechanism to target pulmonary vascular resistance as a modifiable risk factor. This is a novel, modifiable risk factor in this patient population.

A Rare Complication of Maxillomandibular Advancement Surgery: Postoperative Plate Bending Following Emergency Intubation.

Maxillomandibular advancement surgery is a recognized technique for the management of obstructive sleep apnea. Complications for this surgery are not well-documented in the literature. The authors report an unusual case of mandibular plate bending following unplanned postoperative airway management using an oral endotracheal tube in a 65-year-old male. The bent mandibular plate and airway concern required a return to the theater for the replacement of bent plates and tracheostomy placement. This case documents the importance of multidisciplinary team planning for airway-related surgery as well as the need for multidisciplinary team management of postoperative airway management following orthognathic surgery.

Nurse and Social Worker Palliative Telecare Team and Quality of Life in Patients With COPD, Heart Failure, or Interstitial Lung Disease: The ADAPT Randomized Clinical Trial.

Importance: Many patients with chronic obstructive pulmonary disease (COPD), heart failure (HF), and interstitial lung disease (ILD) endure poor quality of life despite conventional therapy. Palliative care approaches may benefit this population prior to end of life. Objective: Determine the effect of a nurse and social worker palliative telecare team on quality of life in outpatients with COPD, HF, or ILD compared with usual care. Design, Setting, and Participants: Single-blind, 2-group, multisite randomized clinical trial with accrual between October 27, 2016, and April 2, 2020, in 2 Veterans Administration health care systems (Colorado and Washington), and including community-based outpatient clinics. Outpatients with COPD, HF, or ILD at high risk of hospitalization or death who reported poor quality of life participated. Intervention: The intervention involved 6 phone calls with a nurse to help with symptom management and 6 phone calls with a social worker to provide psychosocial care. The nurse and social worker met weekly with a study primary care and palliative care physician and as needed, a pulmonologist, and cardiologist. Usual care included an educational handout developed for the study that outlined self-care for COPD, ILD, or HF. Patients in both groups received care at the discretion of their clinicians, which could include care from nurses and social workers, and specialists in cardiology, pulmonology, palliative care, and mental health. Main Outcomes and Measures: The primary outcome was difference in change in quality of life from baseline to 6 months between the intervention and usual care groups (FACT-G score range, 0-100, with higher scores indicating better quality of life, clinically meaningful change ≥4 points). Secondary quality-of-life outcomes at 6 months included disease-specific health status (Clinical COPD Questionnaire; Kansas City Cardiomyopathy Questionnaire-12), depression (Patient Health Questionnaire-8) and anxiety (Generalized Anxiety Disorder-7) symptoms. Results: Among 306 randomized patients (mean [SD] age, 68.9 [7.7] years; 276 male [90.2%], 30 female [9.8%]; 245 White [80.1%]), 177 (57.8%) had COPD, 67 (21.9%) HF, 49 (16%) both COPD and HF, and 13 (4.2%) ILD. Baseline FACT-G scores were similar (intervention, 52.9; usual care, 52.7). FACT-G completion was 76% (intervention, 117 of 154; usual care, 116 of 152) at 6 months for both groups. Mean (SD) length of intervention was 115.1 (33.4) days and included a mean of 10.4 (3.3) intervention calls per patient. In the intervention group, 112 of 154 (73%) patients received the intervention as randomized. At 6 months, mean FACT-G score improved 6.0 points in the intervention group and 1.4 points in the usual care group (difference, 4.6 points [95% CI, 1.8-7.4]; P = .001; standardized mean difference, 0.41). The intervention also improved COPD health status (standardized mean difference, 0.44; P = .04), HF health status (standardized mean difference, 0.41; P = .01), depression (standardized mean difference, -0.50; P < .001), and anxiety (standardized mean difference, -0.51; P < .001) at 6 months. Conclusions and Relevance: For adults with COPD, HF, or ILD who were at high risk of death and had poor quality of life, a nurse and social worker palliative telecare team produced clinically meaningful improvements in quality of life at 6 months compared with usual care. Trial Registration: ClinicalTrials.gov Identifier: NCT02713347.

Conditional inactivation of Foxc1 and Foxc2 in neural crest cells leads to cardiac abnormalities.

Cardiac neural crest cells (cNCCs) are required for normal heart development. cNCCs are a multipotent and migratory cell lineage that differentiates into multiple cell types. cNCCs migrate into the developing heart to contribute to the septation of the cardiac outflow tract (OFT). Foxc1 and Foxc2 are closely related members of the FOX (Forkhead box) transcription factor family and are expressed in cNCC during heart development. However, the precise role of Foxc1 and Foxc2 in cNCCs has yet to be fully described. We found that compound NCC-specific Foxc1;Foxc2 mutant embryos exhibited persistent truncus arteriosus (PTA), ventricular septal defects (VSDs), and thinning of the ventricular myocardium. Loss of Foxc1/c2 expression in cNCCs resulted in abnormal patterns of cNCC migration into the OFT without the formation of the aorticopulmonary septum. Further, loss of Foxc1 expression in cNCCs resulted in normal OFT development but abnormal ventricular septal formation. In contrast, loss of Foxc2 expression in NCCs led to no obvious cardiac abnormalities. Together, we provide evidence that Foxc1 and Foxc2 in cNCCs are cooperatively required for proper cNCC migration, the formation of the OFT septation, and the development of the ventricles. Our data also suggests that Foxc1 expression may play a larger role in ventricular development compared to Foxc2.

Assessing non-Mendelian inheritance in inherited axonopathies.

PURPOSE: Inherited axonopathies (IA) are rare, clinically and genetically heterogeneous diseases that lead to length-dependent degeneration of the long axons in central (hereditary spastic paraplegia [HSP]) and peripheral (Charcot-Marie-Tooth type 2 [CMT2]) nervous systems. Mendelian high-penetrance alleles in over 100 different genes have been shown to cause IA; however, about 50% of IA cases do not receive a genetic diagnosis. A more comprehensive spectrum of causative genes and alleles is warranted, including causative and risk alleles, as well as oligogenic multilocus inheritance. METHODS: Through international collaboration, IA exome studies are beginning to be sufficiently powered to perform a pilot rare variant burden analysis. After extensive quality control, our cohort contained 343 CMT cases, 515 HSP cases, and 935 non-neurological controls. We assessed the cumulative mutational burden across disease genes, explored the evidence for multilocus inheritance, and performed an exome-wide rare variant burden analysis. RESULTS: We replicated the previously described mutational burden in a much larger cohort of CMT cases, and observed the same effect in HSP cases. We identified a preliminary risk allele for CMT in the EXOC4 gene (p value= 6.9 × 10-6, odds ratio [OR] = 2.1) and explored the possibility of multilocus inheritance in IA. CONCLUSION: Our results support the continuing emergence of complex inheritance mechanisms in historically Mendelian disorders.

Fully­automated deep­learning segmentation of pediatric cardiovascular magnetic resonance of patients with complex congenital heart diseases.

BACKGROUND: For the growing patient population with congenital heart disease (CHD), improving clinical workflow, accuracy of diagnosis, and efficiency of analyses are considered unmet clinical needs. Cardiovascular magnetic resonance (CMR) imaging offers non-invasive and non-ionizing assessment of CHD patients. However, although CMR data facilitates reliable analysis of cardiac function and anatomy, clinical workflow mostly relies on manual analysis of CMR images, which is time consuming. Thus, an automated and accurate segmentation platform exclusively dedicated to pediatric CMR images can significantly improve the clinical workflow, as the present work aims to establish. METHODS: Training artificial intelligence (AI) algorithms for CMR analysis requires large annotated datasets, which are not readily available for pediatric subjects and particularly in CHD patients. To mitigate this issue, we devised a novel method that uses a generative adversarial network (GAN) to synthetically augment the training dataset via generating synthetic CMR images and their corresponding chamber segmentations. In addition, we trained and validated a deep fully convolutional network (FCN) on a dataset, consisting of [Formula: see text] pediatric subjects with complex CHD, which we made publicly available. Dice metric, Jaccard index and Hausdorff distance as well as clinically-relevant volumetric indices are reported to assess and compare our platform with other algorithms including U-Net and cvi42, which is used in clinics. RESULTS: For congenital CMR dataset, our FCN model yields an average Dice metric of [Formula: see text] and [Formula: see text] for LV at end-diastole and end-systole, respectively, and [Formula: see text] and [Formula: see text] for RV at end-diastole and end-systole, respectively. Using the same dataset, the cvi42, resulted in [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text] for LV and RV at end-diastole and end-systole, and the U-Net architecture resulted in [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text] for LV and RV at end-diastole and end-systole, respectively. CONCLUSIONS: The chambers' segmentation results from our fully-automated method showed strong agreement with manual segmentation and no significant statistical difference was found by two independent statistical analyses. Whereas cvi42 and U-Net segmentation results failed to pass the t-test. Relying on these outcomes, it can be inferred that by taking advantage of GANs, our method is clinically relevant and can be used for pediatric and congenital CMR segmentation and analysis.

6q25.1 (TAB2) microdeletion is a risk factor for hypoplastic left heart: a case report that expands the phenotype.

INTRODUCTION: Hypoplastic left heart syndrome (HLHS) is a rare but devastating congenital heart defect (CHD) accounting for 25% of all infant deaths due to a CHD. The etiology of HLHS remains elusive, but there is increasing evidence to support a genetic cause for HLHS; in particular, this syndrome is associated with abnormalities in genes involved in cardiac development. Consistent with the involvement of heritable genes in structural heart abnormalities, family members of HLHS patients have a higher incidence of both left- and right-sided valve abnormalities, including bicuspid aortic valve (BAV). CASE PRESENTATION: We previously described (Am J Med Genet A 173:1848-1857, 2017) a 4-generation family with a 6q25.1 microdeletion encompassing TAB2, a gene known to play an important role in outflow tract and cardiac valve formation during embryonic development. Affected adult family members have short stature, dysmorphic facial features, and multiple valve dysplasia, including BAV. This follow-up report includes previously unpublished details of the cardiac phenotype of affected family members. It also describes a baby recently born into this family who was diagnosed prenatally with short long bones, intrauterine growth restriction (IUGR), and HLHS. He was the second family member to have HLHS; the first died several decades ago. Postnatal genetic testing confirmed the baby had inherited the familial TAB2 deletion. CONCLUSIONS: Our findings suggest TAB2 haploinsufficiency is a risk factor for HLHS and expands the phenotypic spectrum of this microdeletion syndrome. Chromosomal single nucleotide polymorphism (SNP) microarray analysis and molecular testing for a TAB2 loss of function variant should be considered for individuals with HLHS, particularly in those with additional non-cardiac findings such as IUGR, short stature, and/or dysmorphic facial features.

Interventions to reduce body temperature to 35 °C to 37 °C in adults and children with traumatic brain injury.

BACKGROUND: Traumatic brain injury (TBI) is a major cause of death and disability, with an estimated 5.5 million people experiencing severe TBI worldwide every year. Observational clinical studies of people with TBI suggest an association between raised body temperature and unfavourable outcome, although this relationship is inconsistent. Additionally, preclinical models suggest that reducing temperature to 35 °C to 37.5 °C improves biochemical and histopathological outcomes compared to reducing temperature to a lower threshold of 33 °C to 35 °C. It is unknown whether reducing body temperature to 35 °C to 37.5 °C in people admitted to hospital with TBI is beneficial, has no effect, or causes harm. This is an update of a review last published in 2014. OBJECTIVES: To assess the effects of pharmacological interventions or physical interventions given with the intention of reducing body temperature to 35 °C to 37.5 °C in adults and children admitted to hospital after TBI. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, Web of Science, and PubMed on 28 November 2019. We searched clinical trials registers, grey literature and references lists of reviews, and we carried out forward citation searches of included studies. SELECTION CRITERIA: We included randomised controlled trials (RCTs) with participants of any age admitted to hospital following TBI. We included interventions that aimed to reduce body temperature to 35 °C to 37.5 °C: these included pharmacological interventions (such as paracetamol, or non-steroidal anti-inflammatory drugs), or physical interventions (such as surface cooling devices, bedside fans, or cooled intravenous fluids). Eligible comparators were placebo or usual care. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed studies for inclusion, extracted data, and assessed risks of bias. We assessed the certainty of the evidence with GRADE. MAIN RESULTS: We included one RCT with 41 participants. This study recruited adult participants admitted to two intensive care units in Australia, and evaluated a pharmacological intervention. Researchers gave participants 1 g paracetamol or a placebo intravenously at four-hourly intervals for 72 hours. We could not be certain whether intravenous paracetamol influenced mortality at 28 days (risk ratio 2.86, 95% confidence interval 0.32 to 25.24). We judged the evidence for this outcome to be very low certainty, meaning we have very little confidence in this effect estimate, and the true result may be substantially different to this effect. We downgraded the certainty for imprecision (because the evidence was from a single study with very few participants), and study limitations (because we noted a high risk of selective reporting bias). This study was otherwise at low risk of bias. The included study did not report the primary outcome for this review, which was the number of people with a poor outcome at the end of follow-up (defined as death or dependency, as measured on a scale such as the Glasgow Outcome Score), or any of our secondary outcomes, which included the number of people with further intracranial haemorrhage, extracranial haemorrhage, abnormal intracranial pressure, or pneumonia or other serious infections. The only other completed trial that we found was of a physical intervention that compared advanced fever control (using a surface cooling device) versus conventional fever control in 12 participants. The trial was published as an abstract only, with insufficient details to allow inclusion, so we have added this to the 'studies awaiting classification' section, pending further information from the study authors or publication of the full study report. We identified four ongoing studies that will contribute evidence to future updates of the review if they measure relevant outcomes and, in studies with a mixed population, report data separately for participants with TBI. AUTHORS' CONCLUSIONS: One small study contributed very low-certainty evidence for mortality to this review. The uncertainty is largely driven by limited research into reduction of body temperature to 35 °C to 37.5 °C in people with TBI. Further research that evaluates pharmacological or physical interventions, or both, may increase certainty in this field. We propose that future updates of the review, and ongoing and future research in this field, incorporate outcomes that are important to the people receiving the interventions, including side effects of any pharmacological agent (e.g. nausea or vomiting), and discomfort caused by physical therapies.

Cross-linguistic f0 differences in bilingual speakers of English and Korean.

Languages may differ in fundamental frequency of voicing (f0), even when they are spoken by a bilingual individual. However, little is known in bilingual/L2 acquisition research about simultaneous bilinguals. With the expectation that speakers who acquired two languages early use f0 differently for each language, this study measured f0 in English-Korean early bilinguals' natural speech. The f0 level was higher for Korean than English, regardless of gender, age, or generational status (early and late bilinguals did not differ). The f0 span showed a language-gender interaction: males' span was larger in Korean, while females' span was larger in English. This study demonstrates that languages differ in f0 independent of speaker anatomy and suggests that children may acquire these differences in early childhood.

A 4D flow MRI evaluation of the impact of shear-dependent fluid viscosity on in vitro Fontan circulation flow.

The Fontan procedure for univentricular heart defects creates a nonphysiologic circulation where systemic venous blood drains directly into the pulmonary arteries, leading to multiorgan dysfunction secondary to chronic low-shear nonpulsatile pulmonary blood flow and central venous hypertension. Although blood viscosity increases exponentially in this low-shear environment, the role of shear-dependent ("non-Newtonian") blood viscosity in this pathophysiology is unclear. We studied three-dimensional (3D)-printed Fontan models in an in vitro flow loop with a Philips 3-T magnetic resonance imaging (MRI) scanner. A 4D flow phase-contrast sequence was used to acquire a time-varying 3D velocity field for each experimental condition. On the basis of blood viscosity of a cohort of patients who had undergone the Fontan procedure, it was decided to use 0.04% xanthan gum as a non-Newtonian blood analog; 45% glycerol was used as a Newtonian control fluid. MRI data were analyzed using GTFlow and MATLAB software. The primary outcome, power loss, was significantly higher with the Newtonian fluid [14.8 (13.3, 16.4) vs. 8.1 (6.4, 9.8)%, medians with 95% confidence interval, P < 0.0001]. The Newtonian fluid also demonstrated marginally higher right pulmonary artery flow, marginally lower shear stress, and a trend toward higher caval flow mixing. Outcomes were modulated by Fontan model complexity, cardiac output, and caval flow ratio. Vortexes, helical flow, and stagnant flow were more prevalent with the non-Newtonian fluid. Our data demonstrate that shear-dependent viscosity significantly alters qualitative flow patterns, power loss, pulmonary flow distribution, shear stress, and caval flow mixing in synthetic models of the Fontan circulation. Potential clinical implications include effects on exercise capacity, ventilation-perfusion matching, risk of pulmonary arteriovenous malformations, and risk of thromboembolism.NEW & NOTEWORTHY Although blood viscosity increases exponentially in low-shear environments, the role of shear-dependent ("non-Newtonian") blood viscosity in the pathophysiology of the low-shear Fontan circulation is unclear. We demonstrate that shear-dependent viscosity significantly alters qualitative flow patterns, power loss, pulmonary flow distribution, shear stress, and caval flow mixing in synthetic models of the Fontan circulation. Potential clinical implications include effects on exercise capacity, ventilation-perfusion matching, risk of pulmonary arteriovenous malformations, and risk of thromboembolism.

Differences in Right Ventricular Physiologic Response to Chronic Volume Load in Patients with Repaired Pulmonary Atresia Intact Ventricular Septum/Critical Pulmonary Stenosis Versus Tetralogy of Fallot.

BACKGROUND: Patients with pulmonary atresia with intact ventricular septum and critical pulmonary stenosis (PAIVS/CPS) have wide variation in right ventricle (RV) size, systolic function, and diastolic function at birth. Establishment of antegrade pulmonary blood flow creates the potential for RV dilation from chronic pulmonary insufficiency. Future surgical decisions are based on RV size and function, largely supported by longitudinal studies of patients with Tetralogy of Fallot (TOF). Given potential differences in RV physiology and lack of similar data in PAIVS/CPS, the objective of this study was to determine differences in RV size, systolic function, and diastolic function between patients with PAIVS/CPS versus TOF. METHODS: We retrospectively collected cardiovascular magnetic resonance (CMR) data in 27 patients with PAIVS/CPS (ages 13.3 ± 8.8 years) and 78 with TOF (11.4 ± 5.4 years). RV volumes, ejection fraction (EF), regurgitant fraction, end-diastolic forward flow across the pulmonary valve, and right atrial cross-sectional area were calculated. RESULTS: There was no difference between the groups in RV end-diastolic volume (RVEDVi), RVEF, or pulmonary regurgitation. RVEF tended to decrease in TOF when RVEDVi exceeded 164 ml/m2. In PAIVS/CPS, RVEDVi less frequently reached 164 ml/m2 and was not associated with RVEF. There was worse RV diastolic dysfunction in PAIVS/CPS, with 1.5 times larger right atrial area and two times higher pulmonary end-diastolic forward flow (p < 0.0001). CONCLUSIONS: Patients with PAIVS/CPS have similar RV size, systolic function, and pulmonary regurgitation as TOF. However, impaired RV diastolic function may limit extremes of RV dilatation and impact long-term management of PAIVS/CPS.

Methamphetamine-Induced Tachydysrhythmia in an Adolescent in Diabetic Ketoacidosis.

BACKGROUND: Diabetic ketoacidosis (DKA) is a common complication affecting patients with type 1 diabetes, and DKA is associated with dehydration and electrolyte abnormalities. Supraventricular tachycardia (SVT), although a common tachydysrhythmia in the pediatric population, remains a rare entity in patients presenting with DKA. CASE REPORT: We describe a case of first-time SVT in an adolescent patient with DKA and recent methamphetamine abuse, with both factors likely predisposing him to develop a tachydysrhythmia. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: SVT can be present in a patient who has concomitant recent stimulant intake and DKA. A trial of abortive therapy, such as adenosine, should be considered upon diagnosis.