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It has long been recognised that a neurological injury can elicit profound systemic complications, from Harvey Cushing who in 1903 described strategies to limit fatal haemodynamic dysfunction during surgical CNS surgery to reports of pulmonary oedema post-seizures in 1908.1
Studies of patients admitted to intensive care with traumatic brain injury (TBI) showed that up to 89% developed non-neurological organ dysfunction, worsening their outcome.2,3 Most commonly patients develop sepsis, respiratory or cardiovascular complications with rates of 75%, 41% and 44% respectively in one cohort.3 Renal and hepatic system involvement is much less common.4 The presence of hypotension, severe respiratory failure or sepsis has been shown to be independent predictors of death and mortality rates rise from 31%–40% for single organ failure to 47%–91% with two organ system failures and up to 100% in cases with three or more organ system failures.
Mild cognitive impairment (MCI) may gradually worsen to dementia, but often remains stable for extended periods of time. Little is known about the predictors of decline to help explain this variation. We aimed to explore whether this heterogeneous course of MCI may be predicted by the presence of Lewy body (LB) symptoms in a prospectively-recruited longitudinal cohort of MCI with Lewy bodies (MCI-LB) and Alzheimer's disease (MCI-AD).
A prospective cohort (n = 76) aged ⩾60 years underwent detailed assessment after recent MCI diagnosis, and were followed up annually with repeated neuropsychological testing and clinical review of cognitive status and LB symptoms. Latent class mixture modelling identified data-driven sub-groups with distinct trajectories of global cognitive function.
Three distinct trajectories were identified in the full cohort: slow/stable progression (46%), intermediate progressive decline (41%) and a small group with a much faster decline (13%). The presence of LB symptomology, and visual hallucinations in particular, predicted decline v. a stable cognitive trajectory. With time zeroed on study end (death, dementia or withdrawal) where available (n = 39), the same subgroups were identified. Adjustment for baseline functioning obscured the presence of any latent classes, suggesting that baseline function is an important parameter in prospective decline.
These results highlight some potential signals for impending decline in MCI; poorer baseline function and the presence of probable LB symptoms – particularly visual hallucinations. Identifying people with a rapid decline is important but our findings are preliminary given the modest cohort size.
Toad bones, sometimes occurring in great numbers in pit features and other contexts in Native American village and mound sites in the Appalachian Summit, have been interpreted as evidence that toads were consumed, used for their purportedly hallucinogenic toad venom, placed as ritual deposits, or naturally entrapped/intrusive. A paucity or lack of bones of the head in some contexts is suggestive of decapitation and consumption of toads. Alternatively, bones of the head may be less preservable, recoverable, or identifiable. This study examines toad remains on Appalachian Summit late precontact and contact period sites, reviews previous experimentation, and presents a new experimental study undertaken to identify agencies of accumulation. We propose that toads were regularly consumed and possibly as part of ritualized events associated with village and mound construction. The temporal and geographic restriction of this practice to the Pisgah and Qualla phases of the Appalachian Summit suggests subsistence ethnicity as alluded to in historical accounts.
Since the launch of the Materials Genome Initiative (MGI) the field of materials informatics (MI) emerged to remove the bottlenecks limiting the pathway towards rapid materials discovery. Although the machine learning (ML) and optimization techniques underlying MI were developed well over a decade ago, programs such as the MGI encouraged researchers to make the technical advancements that make these tools suitable for the unique challenges in materials science and engineering. Overall, MI has seen a remarkable rate in adoption over the past decade. However, for the continued growth of MI, the educational challenges associated with applying data science techniques to analyse materials science and engineering problems must be addressed. In this paper, we will discuss the growing use of materials informatics in academia and industry, highlight the need for educational advances in materials informatics, and discuss the implementation of a materials informatics course into the curriculum to jump-start interested students with the skills required to succeed in materials informatics projects.
Stationary cross-flow vortex N-factors were calculated over the surface of a yawed circular cone using computationally predicted and experimentally observed wavenumber distributions. Surface heat-flux data were obtained on a
half-angle circular cone to investigate the behaviour of the stationary waves at different angles of attack and Reynolds numbers at Mach 6 under quiet-flow conditions in the Boeing/AFOSR Mach-6 Quiet Tunnel at Purdue University. A wavelet analysis was conducted on the experimental surface heat-flux data to construct a spatial mapping of the local largest amplitude wavenumbers of the stationary cross-flow waves, which were between 40 and 80 per circumference. Significant axial and azimuthal variation was observed. The results from the wavelet analysis were used to inform the stability analysis. The computed integration marching directions demonstrated very good agreement with the experimentally observed paths. N-factors were first calculated by integrating the local amplification rate corresponding to the most amplified experimental wavenumbers. The calculations were repeated based on non-dimensional computationally varying wavenumber ratios, which were dimensionalized by the experimental data. The computed N-factors showed good agreement between the two techniques. N-factors were also computed using the computationally predicted most unstable wavenumbers. The results showed decreased agreement with the other two cases, suggesting that this assumption does not properly model the cross-flow transition process.
Healthcare-associated bloodstream infections (HABSIs) are a significant cause of mortality and morbidity in the neonatal intensive care unit (NICU) population. Our objectives were to review the epidemiology of HABSIs in our NICU and to examine the applicability of National Healthcare Safety Network (NHSN) definitions to the NICU population.
We performed a retrospective review of all neonates admitted to the 54-bed, level IV NICU at Yale-New Haven Children’s Hospital with a HABSI between January 1, 2013, and December 31, 2018. Clinical definitions per NICU team and NHSN site-specific definitions used for source identification were compared using the McNemar χ2 test.
We identified 86 HABSIs with an incidence rate of 0.80 per 1,000 patient days. Only 13% of these were CLABSIs. Both CLABSIs and non–catheter-related bloodstream infections occurred primarily in preterm neonates, but the latter were associated with a significantly higher incidence of comorbidities and the need for respiratory support. The NHSN definitions were less likely to identify a source compared to the clinical definitions agreed upon by our NICU treating team (P < .001). Furthermore, 50% of patients without an identified source of infection by NHSN definitions were bacteremic with a mucosal barrier injury organism, likely from gut translocation.
HABSIs occur primarily in premature infants with comorbidities, and CLABSIs account for a small proportion of these infections. With the increasing focus on HABSI prevention, there is a need for better NHSN site-specific definitions for the NICU population to prevent misclassification and direct prevention efforts.
It is a common notion among modern biblical scholars that Origen doubted Paul's authorship of the Epistle to the Hebrews. This article offers an examination of Origen's writings on this question, and shows that the evidence is wildly misrepresented in contemporary discussions. It does this by beginning with Origen's Letter to Africanus, continuing with an overview of his Hebrews citations across his writing career, and concluding with an analysis of his oft-cited comments in Eusebius’ Ecclesiastical History. This examination shows that while Origen suspects Hebrews’ composition to involve more than Paul alone, his surprisingly consistent testimony is that the epistle is indeed Paul's.
Analysis of human remains and a copper band found in the center of a Late Archaic (ca. 5000–3000 cal BP) shell ring demonstrate an exchange network between the Great Lakes and the coastal southeast United States. Similarities in mortuary practices suggest that the movement of objects between these two regions was more direct and unmediated than archaeologists previously assumed based on “down-the-line” models of exchange. These findings challenge prevalent notions that view preagricultural Native American communities as relatively isolated from one another and suggest instead that wide social networks spanned much of North America thousands of years before the advent of domestication.
With the aim to characterize the near-wall flow structures and their interaction with large-scale motions in the log-law region, time-resolved planar and volumetric flow field measurements were performed in the near-wall and log-law region of an adverse pressure gradient turbulent boundary layer following a zero pressure gradient turbulent boundary layer at a friction Reynolds number
. Due to the high spatial and temporal resolution of the measurements, it was possible to resolve and identify uniform-momentum zones in the region
and to relate them with well known coherent flow motions near the wall. The space–time results confirm that the turbulent superstructures have a strong impact even on the very near-wall flow motion and also their alternating appearance in time and intensity could be quantified over long time sequences. Using the time record of the velocity field, rare localized separation events appearing in the viscous sublayer were also analysed. By means of volumetric particle tracking velocimetry their three-dimensional topology and dynamics could be resolved. Based on the results, a conceptual model was deduced that explains their rare occurrence, topology and dynamics by means of a complex interaction process between low-momentum turbulent superstructures, near-wall low-speed streaks and tilted longitudinal and spanwise vortices located in the near-wall region.
Objectives: Craniopharyngioma survivors experience cognitive deficits that negatively impact quality of life. Aerobic fitness is associated with cognitive benefits in typically developing children and physical exercise promotes recovery following brain injury. Accordingly, we investigated cognitive and neural correlates of aerobic fitness in a sample of craniopharyngioma patients. Methods: Patients treated for craniopharyngioma [N=104, 10.0±4.6 years, 48% male] participated in fitness, cognitive and fMRI (n=51) assessments following surgery but before proton radiation therapy. Results: Patients demonstrated impaired aerobic fitness [peak oxygen uptake (PKVO2)=23.9±7.1, 41% impaired (i.e., 1.5 SD<normative mean)], motor proficiency [Bruininks-Oseretsky (BOT2)=38.6±9.0, 28% impaired], and executive functions (e.g., WISC-IV Working Memory Index (WMI)=96.0±15.3, 11% impaired). PKVO2 correlated with better executive functions (e.g., WISC-IV WMI r=.27, p=.02) and academic performance (WJ-III Calculation r=.24, p=.04). BOT2 correlated with better attention (e.g., CPT-II omissions r=.26, p=.04) and executive functions (e.g., WISC-IV WMI r=.32, p=.01). Areas of robust neural activation during an n-back task included superior parietal lobule, dorsolateral prefrontal cortex, and middle and superior frontal gyri (p<.05, corrected). Higher network activation was associated with better working memory task performance and better BOT2 (p<.001). Conclusions: Before adjuvant therapy, children with craniopharyngioma demonstrate significantly reduced aerobic fitness, motor proficiency, and working memory. Better aerobic fitness and motor proficiency are associated with better attention and executive functions, as well as greater activation of a well-established working memory network. These findings may help explain differential risk/resiliency with respect to acute cognitive changes that may portend cognitive late effects. (JINS, 2019, 25, 413–425)
To assess variability in antimicrobial use and associations with infection testing in pediatric ventilator-associated events (VAEs).
Descriptive retrospective cohort with nested case-control study.
Pediatric intensive care units (PICUs), cardiac intensive care units (CICUs), and neonatal intensive care units (NICUs) in 6 US hospitals.
Children≤18 years ventilated for≥1 calendar day.
We identified patients with pediatric ventilator-associated conditions (VACs), pediatric VACs with antimicrobial use for≥4 days (AVACs), and possible ventilator-associated pneumonia (PVAP, defined as pediatric AVAC with a positive respiratory diagnostic test) according to previously proposed criteria.
Among 9,025 ventilated children, we identified 192 VAC cases, 43 in CICUs, 70 in PICUs, and 79 in NICUs. AVAC criteria were met in 79 VAC cases (41%) (58% CICU; 51% PICU; and 23% NICU), and varied by hospital (CICU, 20–67%; PICU, 0–70%; and NICU, 0–43%). Type and duration of AVAC antimicrobials varied by ICU type. AVAC cases in CICUs and PICUs received broad-spectrum antimicrobials more often than those in NICUs. Among AVAC cases, 39% had respiratory infection diagnostic testing performed; PVAP was identified in 15 VAC cases. Also, among AVAC cases, 73% had no associated positive respiratory or nonrespiratory diagnostic test.
Antimicrobial use is common in pediatric VAC, with variability in spectrum and duration of antimicrobials within hospitals and across ICU types, while PVAP is uncommon. Prolonged antimicrobial use despite low rates of PVAP or positive laboratory testing for infection suggests that AVAC may provide a lever for antimicrobial stewardship programs to improve utilization.
Veno-arterial extracorporeal membrane oxygenation is frequently used in patients with cardiac disease. We evaluated short-term outcomes and identified factors associated with hospital mortality in cardiac patients supported with veno-arterial extracorporeal membrane oxygenation.
A retrospective review of patients supported with veno-arterial extracorporeal membrane oxygenation at a university-affiliated children’s hospital was performed.
A total of 253 patients with cardiac disease managed with extracorporeal membrane oxygenation were identified; survival to discharge was 48%, which significantly improved from 39% in an earlier era (1995–2001) (p=0.01). Patients were categorised into surgical versus non-surgical groups on the basis of whether they had undergone cardiac surgery before or not, respectively. The most common indication for extracorporeal membrane oxygenation was extracorporeal cardiopulmonary resuscitation: 96 (51%) in the surgical group and 45 (68%) in the non-surgical group. In a multiple covariate analysis, single-ventricle physiology (p=0.01), duration of extracorporeal membrane oxygenation (p<0.01), and length of hospital stay (p=0.03) were associated with hospital mortality. Weekend or night shift cannulation was associated with mortality in non-surgical patients (p=0.05).
We report improvement in survival compared with an earlier era in cardiac patients supported with extracorporeal membrane oxygenation. Single-ventricle physiology continues to negatively impact survival, along with evidence of organ dysfunction during extracorporeal membrane oxygenation, duration of extracorporeal membrane oxygenation, and length of stay.
We observed pediatric S. aureus hospitalizations decreased 36% from 26.3 to 16.8 infections per 1,000 admissions from 2009 to 2016, with methicillin-resistant S. aureus (MRSA) decreasing by 52% and methicillin-susceptible S. aureus decreasing by 17%, among 39 pediatric hospitals. Similar decreases were observed for days of therapy of anti-MRSA antibiotics.
The evolution of material wealth-based inequality is an important topic in archaeological research. While a number of explanatory models have been proposed, rarely have they been adequately tested. A significant challenge to testing such models concerns our ability to define distinct, temporally short-term, residential occupations in the archaeological record. Sites often lack evidence for temporally persistent inequality, or, when present, the palimpsest nature of the deposits often make it difficult to define the processes of change on scales that are fine enough to evaluate nuanced model predictions. In this article, we use the detailed record of Housepit 54 from the Bridge River site, interior British Columbia, to evaluate several alternative hypotheses regarding the evolution of persistent material wealth-based inequality. Results of our analyses indicate that inequality appeared abruptly coincident with a decline in intra-house cooperation associated with population packing and the initiation of periodic subsistence stress. We conclude that persistent inequality in this context was a byproduct of altered social networks linked to a Malthusian transition and ceiling.
Migration was a key social process contributing to the creation of the ‘Chaco World’ between AD 800 and 1200. Dynamic social network analysis allows for evaluation of several migration scenarios, and demonstrates that Chaco’s earliest ninth-century networks show interaction with areas to the west and south, rather than migration to the Canyon from the Northern San Juan. By the late eleventh century, Chaco Canyon was tied strongly to the Middle and Northern San Juan, while a twelfth-century retraction of networks separated the Northern and Southern San Juan areas prior to regional depopulation. Understanding Chaco migration is important for comprehending both its uniqueness in U.S. Southwest archaeology and for comparison with other case studies worldwide.