Better outcome prediction could assist in reliable quantification and classification of traumatic brain injury (TBI) severity to support clinical decision-making. We developed a multifactorial model ...combining quantitative electroencephalography (qEEG) measurements and clinically relevant parameters as proof of concept for outcome prediction of patients with moderate to severe TBI.
Continuous EEG measurements were performed during the first 7 days of ICU admission. Patient outcome at 12 months was dichotomized based on the Extended Glasgow Outcome Score (GOSE) as poor (GOSE 1-2) or good (GOSE 3-8). Twenty-three qEEG features were extracted. Prediction models were created using a Random Forest classifier based on qEEG features, age, and mean arterial blood pressure (MAP) at 24, 48, 72, and 96 h after TBI and combinations of two time intervals. After optimization of the models, we added parameters from the International Mission for Prognosis And Clinical Trial Design (IMPACT) predictor, existing of clinical, CT, and laboratory parameters at admission. Furthermore, we compared our best models to the online IMPACT predictor.
Fifty-seven patients with moderate to severe TBI were included and divided into a training set (n = 38) and a validation set (n = 19). Our best model included eight qEEG parameters and MAP at 72 and 96 h after TBI, age, and nine other IMPACT parameters. This model had high predictive ability for poor outcome on both the training set using leave-one-out (area under the receiver operating characteristic curve (AUC) = 0.94, specificity 100%, sensitivity 75%) and validation set (AUC = 0.81, specificity 75%, sensitivity 100%). The IMPACT predictor independently predicted both groups with an AUC of 0.74 (specificity 81%, sensitivity 65%) and 0.84 (sensitivity 88%, specificity 73%), respectively.
Our study shows the potential of multifactorial Random Forest models using qEEG parameters to predict outcome in patients with moderate to severe TBI.
The bottom-up approach of the Nationally Determined Contributions (NDCs) in the Paris Agreement has led countries to self-determine their greenhouse gas (GHG) emission reduction targets. The planned ...‘ratcheting-up’ process, which aims to ensure that the NDCs comply with the overall goal of limiting global average temperature increase to well below 2 °C or even 1.5 °C, will most likely include some evaluation of ‘fairness’ of these reduction targets. In the literature, fairness has been discussed around equity principles, for which many different effort-sharing approaches have been proposed. In this research, we analysed how country-level emission targets and carbon budgets can be derived based on such criteria. We apply novel methods directly based on the global carbon budget, and, for comparison, more commonly used methods using GHG mitigation pathways. For both, we studied the following approaches: equal cumulative per capita emissions, contraction and convergence, grandfathering, greenhouse development rights and ability to pay. As the results critically depend on parameter settings, we used the wide authorship from a range of countries included in this paper to determine default settings and sensitivity analyses. Results show that effort-sharing approaches that (i) calculate required reduction targets in carbon budgets (relative to baseline budgets) and/or (ii) take into account historical emissions when determining carbon budgets can lead to (large) negative remaining carbon budgets for developed countries. This is the case for the equal cumulative per capita approach and especially the greenhouse development rights approach. Furthermore, for developed countries, all effort-sharing approaches except grandfathering lead to more stringent budgets than cost-optimal budgets, indicating that cost-optimal approaches do not lead to outcomes that can be regarded as fair according to most effort-sharing approaches.
Microplastic pollution in the environment is a growing concern in today's world. Wind-eroded sediment, as an environmental transport pathway of microplastics, can result in environmental and human ...exposure far beyond its sources. For the first time, this study investigates the presence of microplastics in wind-eroded sediments from different land uses in the Fars Province, Iran. Eleven test plots were selected based on land use and wind erosion risk. On each plot, wind erosion was simulated using a portable wind tunnel and the eroded sediment was collected for further analysis aimed at measuring light density microplastics (LDMP). The LDMPs were extracted in both soil and wind-eroded sediment using a floatation method and then further examined using microscopy. Annual LDMP transport by wind erosion was estimated using wind data from the study areas. LDMPs were detected in six study areas in the Fars Province which are highly prone to wind erosion. Although LDMPs were found mostly in agricultural land, it was also detected in the soils and sediments from two natural areas. The total concentrations of LDMPs in polluted areas were 6.91 and 20.27 mg kg−1 of microplastics in soil and wind-eroded sediments, respectively. The enrichment ratio for LDMP ranged from 2.83 to 7.63 in different areas. The erosion rate of LDMP ranged from 0.08 to 1.48 mg m−2 min−1. The results of this study confirmed the key role of wind erosion in the spread of microplastics in terrestrial environments which could form an exposure risk to humans via direct inhalation of the particles transported with the dust.
Display omitted
•This is the first study about transport of microplastics by wind erosion.•Microplastics were found in wind-eroded sediments of agricultural and natural areas.•Microplastic concentrations ranged from 67 to 1133 particles kg−1.•Wind-eroded sediments were enriched with microplastics with the ratio of 2.83 to 7.63.•Our study questions the direct exposure of microplastics to humans by wind erosion.
Nanostructured high-entropy materials Haché, Michel J. R.; Cheng, Changjun; Zou, Yu
Journal of materials research,
04/2020, Letnik:
35, Številka:
8
Journal Article
Recenzirano
Odprti dostop
In the past decade, the emergence of high-entropy alloys (HEAs) and other high-entropy materials (HEMs) has brought about new opportunities in the development of novel materials for high-performance ...applications. In combining solid-solution (SS) strengthening with grain-boundary strengthening, new material systems—nanostructured or nanocrystalline (NC) HEAs or HEMs—have been developed, showing superior combined mechanical and functional properties compared with conventional alloys, HEAs, and NC metals. This article reviews the processing methods, materials, mechanical properties, thermal stability, and functional properties of various nanostructured HEMs, particularly NC HEAs. With such new nanostructures and alloy compositions, many interesting phenomena and properties of such NC HEAs have been unveiled, for example, extraordinary microstructural and mechanical thermal stability. As more HEAs or HEMs are being developed, a new avenue of research is to be exploited. The article concludes with perspectives about future directions in this field.
While several clinical studies have shown that HIV-1 infection is associated with increased permeability of the intestinal tract, there is very little understanding of the mechanisms underlying ...HIV-induced impairment of mucosal barriers. Here we demonstrate that exposure to HIV-1 can directly breach the integrity of mucosal epithelial barrier, allowing translocation of virus and bacteria. Purified primary epithelial cells (EC) isolated from female genital tract and T84 intestinal cell line were grown to form polarized, confluent monolayers and exposed to HIV-1. HIV-1 X4 and R5 tropic laboratory strains and clinical isolates were seen to reduce transepithelial resistance (TER), a measure of monolayer integrity, by 30-60% following exposure for 24 hours, without affecting viability of cells. The decrease in TER correlated with disruption of tight junction proteins (claudin 1, 2, 4, occludin and ZO-1) and increased permeability. Treatment of ECs with HIV envelope protein gp120, but not HIV tat, also resulted in impairment of barrier function. Neutralization of gp120 significantly abrogated the effect of HIV. No changes to the barrier function were observed when ECs were exposed to Env defective mutant of HIV. Significant upregulation of inflammatory cytokines, including TNF-alpha, were seen in both intestinal and genital epithelial cells following exposure to HIV-1. Neutralization of TNF-alpha reversed the reduction in TERs. The disruption in barrier functions was associated with viral and bacterial translocation across the epithelial monolayers. Collectively, our data shows that mucosal epithelial cells respond directly to envelope glycoprotein of HIV-1 by upregulating inflammatory cytokines that lead to impairment of barrier functions. The increased permeability could be responsible for small but significant crossing of mucosal epithelium by virus and bacteria present in the lumen of mucosa. This mechanism could be particularly relevant to mucosal transmission of HIV-1 as well as immune activation seen in HIV-1 infected individuals.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
We have excellent skills to extract sex from visual assessment of human faces, but assessing sex from human brain rhythms seems impossible. Using deep convolutional neural networks, with unique ...potential to find subtle differences in apparent similar patterns, we explore if brain rhythms from either sex contain sex specific information. Here we show, in a ground truth scenario, that a deep neural net can predict sex from scalp electroencephalograms with an accuracy of >80% (p < 10
), revealing that brain rhythms are sex specific. Further, we extracted sex-specific features from the deep net filter layers, showing that fast beta activity (20-25 Hz) and its spatial distribution is a main distinctive attribute. This demonstrates the ability of deep nets to detect features in spatiotemporal data unnoticed by visual assessment, and to assist in knowledge discovery. We anticipate that this approach may also be successfully applied to other specialties where spatiotemporal data is abundant, including neurology, cardiology and neuropsychology.
OBJECTIVE:To evaluate the value of continuous electroencephalography in early prognostication in patients treated with hypothermia after cardiac arrest.
DESIGN:Prospective cohort study.
...SETTING:Medical intensive care unit.
PATIENTS:Sixty patients admitted to the intensive care unit for therapeutic hypothermia after cardiac arrest.
INTERVENTION:None.
MEASUREMENTS AND MAIN RESULTS:In all patients, continuous electroencephalogram and daily somatosensory evoked potentials were recorded during the first 5 days of admission or until intensive care unit discharge. Neurological outcomes were based on each patient’s best achieved Cerebral Performance Category score within 6 months. Twenty-seven of 56 patients (48%) achieved good neurological outcome (Cerebral Performance Category score 1–2).At 12 hrs after resuscitation, 43% of the patients with good neurological outcome showed continuous, diffuse slow electroencephalogram rhythms, whereas this was never observed in patients with poor outcome.The sensitivity for predicting poor neurological outcome of low-voltage and isoelectric electroencephalogram patterns 24 hrs after resuscitation was 40% (95% confidence interval 19%–64%) with a 100% specificity (confidence interval 86%–100%), whereas the sensitivity and specificity of absent somatosensory evoked potential responses during the first 24 hrs were 24% (confidence interval 10%–44%) and 100% (confidence interval87%–100%), respectively. The negative predictive value for poor outcome of low-voltage and isoelectric electroencephalogram patterns was 68% (confidence interval 50%–81%) compared to 55% (confidence interval 40%–60%) for bilateral somatosensory evoked potential absence, both with a positive predictive value of 100% (confidence interval 63%–100% and 59%–100% respectively). Burst-suppression patterns after 24 hrs were also associated with poor neurological outcome, but not inevitably so.
CONCLUSIONS:In patients treated with hypothermia, electroencephalogram monitoring during the first 24 hrs after resuscitation can contribute to the prediction of both good and poor neurological outcome. Continuous patterns within 12 hrs predicted good outcome. Isoelectric or low-voltage electroencephalograms after 24 hrs predicted poor outcome with a sensitivity almost two times larger than bilateral absent somatosensory evoked potential responses.
In the context of large-eddy simulation (LES) of Diesel engine combustion, two LES combustion models are proposed. Their ability to predict autoignition delays and heat release of an autoigniting ...liquid α-methylnaphthalene/n-decane jet injected into a constant-volume chamber under Diesel-like conditions is assessed. These models retain the tabulation of a complex chemistry scheme using autoigniting homogeneous reactors (HR) at constant pressure. This allows accounting for the chemical complexity of heavy hydrocarbon fuels over the wide range of conditions representative for Diesel engines, at comparatively low CPU time overhead. The tabulated homogeneous reactor (THR) approach assumes the local structure of the reaction zone to be that of an HR, while the approximated diffusion flame (ADF) approach is based on autoigniting strained diffusion flames. Two variants of each approach are considered, either neglecting sub-grid-scale mixture fraction variance (THR and ADF models), or accounting for it via a presumed β-PDF (THR-pdf and ADF–PCM models). LES results indicate that the ADF model assuming diffusion flame structures tends to predict faster propagation of the combustion toward less reactive mixture fractions then the THR model. Moreover, neglecting the mixture fraction fluctuations strongly overestimates initial experimental heat release rates after autoignition. Comparison between models shows that this assumption yields higher reaction rates and temperature levels close to the stoichiometric mixture fraction zones. Predictions in terms of autoignition are remarkably close with all models, and exhibit very few variations from one realization to the other. Variations in global heat release rate become more apparent for different realizations at later instants, in relation to the interaction of large flow scales with combustion.
We investigate the quantum Heisenberg model on the pyrochlore lattice for a generic spinSin the presence of nearest-neighborJ1and second-nearest-neighborJ2exchange interactions. By employing the ...pseudofermion functional renormalization group method, we find, forS=1/2andS=1, an extended quantum-spin-liquid phase centered aroundJ2=0, which is shown to be robust against the introduction of breathing anisotropy. The effects of temperature, quantum fluctuations, breathing anisotropies, and aJ2coupling on the nature of the scattering profile, and the pinch points, in particular, are studied. For the magnetic phases of theJ1−J2model, quantum fluctuations are shown to renormalize phase boundaries compared to the classical model and to modify the ordering wave vectors of spiral magnetic states, while no new magnetic orders are stabilized.