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Glaucoma is among the leading causes of blindness worldwide that is characterized by irreversible damage to the retinal ganglion cell axons in the lamina cribrosa (LC) region of the optic nerve head (ONH), most often associated with elevated intraocular pressure (IOP). The LC is a porous, connective tissue structure that provides mechanical support to the axons as they exit the eye and the biomechanics of the LC microstructure likely play a crucial role in protecting the axons passing through it. There is a limited knowledge of the IOP-driven biomechanics of the LC microstructure, primarily due to its small size and the difficulty with imaging the LC both in vitro and in vivo. We present finite element (FE) models of three human eye posterior poles that include the LC microstructure and interspersed neural tissues (NT) composed of retinal axons that are constructed directly from segmented, binary images of the LC. These models were used to estimate the stresses and strains in the LC and NT for an acute IOP el and loading conditions. Results are presented for three human donor eyes, showing that prior modeling approaches underestimate the stresses and strains in the laminar microstructure. We constructed models from image stacks of the segmented microstructure (Matlab code included) using an approach that is ideal for modeling any structure with a complex microstructure composed of different materials, such as trabecular bone, lung, and tissue engineering scaffolds.Ethylene is a small hydrocarbon gas widely used in the chemical industry. Annual worldwide production currently exceeds 150 million tons, producing considerable amounts of CO2 contributing to climate change. The need for a sustainable alternative is therefore imperative. Ethylene is natively produced by several different microorganisms, including Pseudomonas syringae pv. phaseolicola via a process catalyzed by the ethylene-forming enzyme (EFE), subsequent heterologous expression of EFE has led to ethylene production in non-native bacterial hosts including Escherichia coli and cyanobacteria. However, solubility of EFE and substrate availability remain rate-limiting steps in biological ethylene production. We employed a combination of genome-scale metabolic modelling, continuous fermentation, and protein evolution to enable the accelerated development of a high efficiency ethylene producing E. coli strain, yielding a 49-fold increase in production, the most significant improvement reported to date. Furthermore, we have clearly demonstrated that this increased yield resulted from metabolic adaptations that were uniquely linked to EFE (wild type versus mutant). Our findings provide a novel solution to deregulate metabolic bottlenecks in key pathways, which can be readily applied to address other engineering challenges.

We investigated whether non-pharmaceutical interventions (NPIs) reduce winter-prevalent respiratory viral infections represented by a respiratory syncytial virus (RSV) and influenza virus (IFV) during the winter in Korea.

The Korean Influenza and Respiratory Virus Monitoring System database was used. From January 2016 through January 2021, the weekly positivity of respiratory viruses and the weekly number of hospitalizations with acute respiratory infections were collected. The NPI period was defined as February 2020-January 2021. We analyzed whether hospitalization and sample positivity by respiratory viruses changed after NPIs. Bayesian structural time-series models and Poisson analyses were used. Data from other countries/regions reporting positive rates of RSV and IFV were also investigated.

Compared with the pre-NPI period, the positive rates of RSV and IFV decreased significantly to 19% and 6%, and 23% and 6% of the predicted value. Also, hospitalization significantly decreased to 9% and 8%, and 10% and 5% of the predicted value. Smad signaling The positive rates of IFV in 14 countries during the NPI period were almost 0, whereas sporadic outbreaks of RSV occurred in some countries.

No RSV and IFV winter epidemics were observed during the 2020-2021 season in Korea.

No RSV and IFV winter epidemics were observed during the 2020-2021 season in Korea.Depressed right ventricular ejection fraction (RVEF) has clear prognostic significance in patients with pulmonary arterial hypertension (PAH). Accordingly, improvements in RVEF represent a desirable end-point in the development of PAH therapies. However, current methods for determination of RVEF require measurement of RV volume and are relatively complex and costly. Here, we validate a novel method for quantitative estimation of RVEF in rats based entirely upon analysis of readily available RV pressure waveforms that eliminates the need for simultaneous volume measurement and can be rapidly applied. Right ventricular pressure and volume (conductance catheter) measurements acquired from 15 rats (7 controls, 8 sugen/hypoxia PAH; 220-250 g) were used for the study. Over the same 10 beat interval, RVEF was directly measured from the volume signal and estimated from the pressure signal. Simultaneous measures were compared by linear regression and Bland-Altman analysis to define bias (accuracy) and precision. Measured RVEF ranged from 0.19 to 0.60 (mean 0.44 ± 0.10) and estimated from 0.19 to 0.52 (mean 0.42 ± 0.09). Across the dataset there was strong correlation (r2 = 0.813), with minimal bias (0.01) and an overall error of 20% consistent with acceptable accuracy and precision. Study results support the potential utility of a method based entirely upon analysis of the RV pressure waveform for assessing drug effects on RVEF in rat models of PAH.

To determine diagnostic value of morphological features of horizontal laminar fracture (HLF) and vertical laminar fracture (VLF) for diagnosis of posterior ligamentous complex (PLC) injury.

This retrospective review comprised 271 consecutive patients with acute thoracolumbar fractures presenting to a Level 1 trauma center between January 2014 and January 2021. Two reviewers evaluated computed tomography and magnetic resonance imaging. VLFs were subclassified based on length and depth of lamina involved, as follows type 1, full-length complete; type 2, full-length incomplete; type 3, partial-length complete or incomplete. HLFs were subclassified as follows bilateral versus unilateral, displaced >2 mm versus nondisplaced, and lamina-only versus laminar and pedicle. We examined the diagnostic accuracy and the univariate and multivariate associations of laminar fracture subtypes with PLC injury as defined by black stripe discontinuity.

Bilateral HLFs, laminar and pedicle fractures, displaced HLFs, and type 1 VLFs yielded a high positive predictive value for PLC injury (95%, 91%, 100%, and 86%, respectively).