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Modulating the behavior of ethyl cellulose-based oleogels: The impact food-grade amphiphilic small molecules on structural, mechanical, and rheological properties
This work evaluates the ability of various lipid-based amphiphilic small molecules (ASMs) to modulate the mechanical and rheological properties of oleogels principally structured by ethyl cellulose (EC). Six ASMs varying in the chemical structure of their polar headgroups were used to produce EC-ASM oleogels. Stearic acid (StAc), monoacylglycerol (MAG), sodium stearoyl lactylate (SSL), and citric acid esters of monoglycerides (CITREM) all provided a dramatic enhancement in gel strength, while lactic acid (LACTEM) and acetic acid (ACETEM) esters produced only a marginal increase. Those additives which crystallized above 20 °C displayed pronounced changes in their network organization and crystal morphology in the presence of EC. Differences in the solid/liquid phase change behavior were also observed in select samples using differential scanning calorimetry. Both the small and large amplitude oscillatory shear responses were dependent on the ASM which was dependent on the chemistry of the headgroup, crystal network organization, and ability to plasticize the polymer network. The extent of thixotropic recovery was largely dependent on the polarity of functional groups in the ASMs, but was also influenced by the formation of a secondary crystal network. In general, ASMs which formed larger, system-spanning crystal networks (MAG, StAc) produced more brittle gels, while the highly hydrophilic, charged headgroup of SSL promoted a homogeneous distribution of small crystals, resulting in a tougher material. In the absence of a crystal network, stronger polar species in the ASM headgroup produced higher gel strength and increased elasticity. Thus, both ASM chemical structure and crystallization properties strongly contribute to the functionality of the resulting combined oleogelator systems
Surgical management of a lateral sphenoid sinus encephalocele: 2-Dimensional operative video.
Encephaloceles are considered rare with an approximate incidence of 1 in 35,000, and sphenoid encephaloceles are even more uncommon.2 Two types of sphenoid encephaloceles exist: medial perisellar encephaloceles, and lateral sphenoidal encephaloceles. Surgical correction of the lateral sphenoid recess encephalocele is achieved via one of two endoscopic approaches: extended sphenoidotomy or transpterygopalatine. Extended sphenoidotomy is preferred if the angle between the access door and lateral extension of bone defect is greater than 35°1. Otherwise, the transpterygopalatine approach is used. Intraoperative video demonstrating an extended sphenoidotomy approach to correcting a lateral recess sphenoidal encephalocele has not previously been published. Here we present a case of a 41-year-old female who presented with meningitis, a cerebrospinal fluid leak, and an incidental sphenoid mass. Brain MRI redemonstrated the mass in the sphenoid sinus consistent with an encephalocele occupying Sternbergs Canal. The patient consented to the procedure. The video demonstrates the skull base approach, encephalocele extraction, collagen inlay, and nasal septal bone and vascularized pedicled nasoseptal flap placement. Postoperative imaging confirmed the placement of the collagen inlay and nasal septal bone autograft. The patient recovered from surgery and was discharged on post-operative day 3 with no cerebrospinal fluid (CSF) leak recurrence. Postoperative follow up demonstrated viable nasoseptal graft without evidence of CSF leak. For patients with favorable anatomy, an extended sphenoidotomy approach to lateral sphenoid sinus encephalocele resection is a preferred alternative to the transpterygoid approach. This surgical video demonstrates the technique for managing lateral sphenoid sinus encephaloceles occupying Sternbergs canal, including endonasal approach, encephalocele resection and posterior sphenoid wall repair
XOLARIS: A 24-Month, Prospective, Natural History Study of 201 Participants with Retinitis Pigmentosa GTPase Regulator-Associated X-Linked Retinitis Pigmentosa.
OBJECTIVE: To improve the understanding of the natural disease progression of retinitis pigmentosa GTPase regulator (RPGR)-associated X-linked retinitis pigmentosa (XLRP). DESIGN: A multicenter, prospective, observational natural history study over 24 months. PARTICIPANTS: Male participants aged ≥7 years with a pathogenic variant in the RPGR gene, a best-corrected visual acuity (BCVA) score of ≥34 ETDRS letters, and a mean 68-loci retinal sensitivity (assessed by microperimetry) of 0.1 to 20 decibels (dB). METHODS: Participants were divided into subgroups based on their BCVA score at baseline: 34 to 73 (lower BCVA) or ≥74 (higher BCVA) ETDRS letters. There were 7 visits over 24 months. MAIN OUTCOME MEASURES: Change from baseline in BCVA, retinal sensitivity, low luminance visual acuity (LLVA), fixation stability, contrast sensitivity, visual field, anatomical measures, 25-item Visual Function Questionnaire (VFQ-25), intraocular pressure, and adverse events (AEs). RESULTS: Overall, 201 participants were included. The mean (standard deviation [SD]) age was 30.3 (11.9) years in the lower BCVA subgroup (n = 170) and 27.7 (10.1) years in the higher BCVA subgroup (n = 31). The study eye baseline mean (SD) BCVA scores were 59.4 (10.30) and 77.3 (3.95) in the lower and higher BCVA subgroups, respectively; the lower BCVA subgroup had lower retinal sensitivity in the study eye at baseline than the higher BCVA subgroup. Over 24 months, there were small observed changes in BCVA, retinal sensitivity, LLVA, fixation, contrast sensitivity, and fundus photography findings. There were observed mean (SD) changes at 24 months in the lower and higher BCVA subgroups of -1.01 (4.67) and 0.03 (5.83) dB-steradians in the volume of full-field hill of vision, -330.6 (869.51) and -122.7 (22.01) μm in distance from foveal center to the nearest border of preserved fundus autofluorescence, -104.3 (277.80) and -207.1 (171.01) μm in central ellipsoid width, and -2.8 (9.7) and -0.6 (7.6) in VFQ-25 composite score, respectively. There was 1 death from completed suicide. There were no ocular serious adverse events, and most AEs were mild/moderate. CONCLUSIONS: This study provides evidence of the slow natural progression of XLRP over 24 months in both subgroups and provides important functional, anatomical, and safety data. FINANCIAL DISCLOSURES: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article
Efficient separation of carbon dioxide and methane in high-pressure and wet gas mixtures using Zr-MOF-808
The capture and separation of carbon dioxide (CO2) has been the focus of a plethora of research in order to mitigate its emissions and contribute to global development. Given that CO2 is commonly found in natural gas streams, there have been efforts to seek more efficient materials to separate gaseous mixtures such as CO2/CH4. However, there are only a few reports regarding adsorption processes within pressurized systems. In the offshore scenario, natural gas streams still exhibit high moisture content, necessitating a greater understanding of processes in moist systems. In this article, a metal-organic framework synthesis based on zirconium (MOF-808) was carried out through a conventional solvothermal method and autoclave for the adsorption of CO2 and CH4 under different temperatures (45–65 °C) and pressures up to 100 bar. Furthermore, the adsorption of humid CO2 was evaluated using thermal analyses. The MOF-808 synthesized in autoclave showed a high surface area (1502 m2/g), a high capacity for CO2 adsorption at 50 bar and 45 °C and had a low selectivity to capture CH4 molecules. It also exhibited a fine stability after five cycles of CO2 adsorption and desorption at 50 bar and 45 °C − as confirmed by structural post-adsorption analyses while maintaining its adsorption capacity and crystallinity. Furthermore, it can be observed that the adsorption capacity increased in a humid environment, and that the adsorbent remained stable after adsorption cycles in the presence of moisture. Finally, it was possible to confirm the occurrence of physisorption processes through nuclear magnetic resonance (NMR) analyses, thus validating the choice of mild temperatures for regeneration and contributing to the reduction of energy consumption in processing plants
Recollection and familiarity support auditory working memory in a manner analogous to visual working memory
Prior work has suggested that visual working memory as measured in change detection tasks can be based on recollection, whereby participants consciously identify a specific feature of a stimulus that has changed, or on familiarity, whereby participants sense that a change has occurred but are unable to consciously access what has changed. Whether recollection and familiarity also contribute to auditory working memory is unclear. The present study aims to address that gap in knowledge by having participants make confidence judgments in change detection tests for speech sounds and pure tones. The results indicated that both recollection and familiarity contribute to auditory working memory across a variety of conditions, and showed that these two processes are functionally dissociable. With speech sounds, subjects were better able to detect syllable changes compared to tone or location changes, and this benefit reflected a selective increase in recollection rather than familiarity. Moreover, for pure tones, both recollection and familiarity also contributed to performance, but recollection was found to be selectively eliminated under stimulus-limited test conditions (i.e., noise-masked, brief dichotic presentations). The results indicate that recollection and familiarity contribute to auditory working memory in a manner that is functionally similar to that observed in visual working memory
AI for Green Spaces: Leveraging Autonomous Navigation and Computer Vision for Park Litter Removal
There are 50 billion pieces of litter in the U.S. alone. Grass fields contribute to this problem because picnickers tend to leave trash on the field. We propose building a robot that can autonomously navigate, identify, and pick up trash in parks. To autonomously navigate the park, we used a Spanning Tree Coverage (STC) algorithm to generate a coverage path the robot could follow. To navigate this path, we successfully used Real-Time Kinematic (RTK) GPS, which provides a centimeter-level reading every second. For computer vision, we utilized the ResNet50 Convolutional Neural Network (CNN), which detects trash with 94.52% accuracy. For trash pickup, we tested multiple design concepts. We select a new pickup mechanism that specifically targets the trash we encounter on the field. Our solution achieved an overall success rate of 80%, demonstrating that autonomous trash pickup robots on grass fields are a viable solution
National Costs for Cardiovascular-Related Hospitalizations and Inpatient Procedures in the United States, 2016 to 2021
The current economic burden of cardiovascular (CV)-related hospitalizations grouped by diagnoses and procedures in the United States has not been well characterized. The objective was to identify current trends in CV-related hospitalizations, procedural utilization, and health care costs using the most recent 6 years of hospitalization data. A retrospective analysis of discharge data from the National Inpatient Sample database was conducted to determine trends in CV-related hospitalizations, costs, and procedures for each year from 2016 to the most recent available dataset, 2021. Total CV-related costs were adjusted to and reported in 2023 dollars. In 2021, there were 4,687,370 CV-related hospitalizations at a cost of 18.5 billion, followed by non-ST-elevation myocardial infarction at 10.9 billion. Significant upward trends in costs from 2016 to 2021 were observed for heart failure, stroke, atrial fibrillation, ST-elevation myocardial infarction, chest pain, hypertensive emergency, ventricular tachycardia, aortic dissection, sudden cardiac death, pericarditis, supraventricular tachycardia, and pulmonary heart disease. Over the 6 observational years, total costs increased by over 131.3 billion. For all years, coronary procedures were the most performed, followed by extracorporeal membrane oxygenation, non-bypass peripheral vascular surgery, pacemaker placement, and coronary artery bypass graft surgery. Both transcatheter aortic valve replacement and MitraClip procedures demonstrated significant upward trends from 2016 to 2021. Overall, from the years 2016 to 2021, CV-related hospitalizations, costs, and procedures demonstrated upward trends. In conclusion, CV disease remains a high burden in the hospital setting with tremendous health care costs
A Robust Transfinite Element Method for the Solution of Nonlinear Aeroelastic Fluid Structure Interaction Systems Expressed as a Monolithic Set of Equations
Gradient Adaptive Transfinite Elements (GATE) offer a generic method to implement arbitrary high-order numerical solutions to existing finite element formulations. GATE are a family of elements that are formulated using transfinite interpolation, a generic blending-based interpolation technique that can construct optimal interpolation functions about areas and volumes. The arbitrary nature of transfinite elements allows for the creation of elements that can serve a variety of useful purposes. Elements can be constructed to transition from a region using high-order representation to low-order representation. High-order representation is important in capturing large gradients, especially in regions near geometric boundaries. Without such capability, one is either left with the choice of paying a high cost to implement high-order representation across the entire domain, or excessively refining the low-order representation near the high gradient region. The high order nature of GATE is well suited for a Direct Numerical Simulation (DNS) of the Navier Stokes equations. In this present work, we apply GATE to find DNS solutions of the Navier Stokes equations and coupled Fluid-Structure Interaction (FSI) problems.The high-order representation provided by GATE is not limited to the representation of the solution but can be used in the same manner for the geometry. This is typically done using isoparametric mapping, a technique that maps the geometry to an element reference domain using the same basis functions used for the representation of the field. GATE can also be used as a parametric mapping with a high-order representation or exact representation used to represent the boundary geometry. The ability of GATE to transition between high-order and low-order regions is well suited for parametric mapping where a high degree of mapping accuracy is needed at the boundary and low-order mapping accuracy is acceptable in the field.GATE family elements can also be used for general C1 conforming interpolation to solve higher-order governing equations or provide convenience in the evaluation of quantities that depend on the gradient of the solution. This has an added benefit in reducing the total number of degrees of freedom in the numerical representation of the system while still retaining high-order accuracy.GATE is well suited for the numerical representation of FSI systems. FSI involves the coupling between fluid and structure domains. The quality of the results of an FSI simulation depends on the accurate representation of the coupling across the fluid-structure interface. A monolithic formulation of the FSI system couples the fluid and structural domains together as a single interdependent set of equations. Such a formulation has an advantage over other methods that partition the fluid and structural domains and solve them independently. The solution of a coupled monolithic system exactly represents the coupled system, there is no place to introduce a bias to one domain or misrepresentation of the interface between the domains. Additionally, the coupling can be accounted for in the linearization of the system and improve convergence when an iterative nonlinear solver is employed. Using GATE on the fluid and structure interface offers a convenient means to ensure conformity between the two domains.We developed a research tool to implement GATE for a variety of simulations performed for this dissertation. This was done because existing finite element software draws from libraries with preexisting element formulations based on traditional methods. Many aspects of existing software depend on the layout of nodes in the elements for the assembly required to construct the complete finite element system and thus would require significant changes to incorporate the flexibility of GATE. With the lessons learned from this effort, the implementation of GATE into existing software will be less of a challenge and would be beneficial so GATE could benefit from a performance optimized software implementation.This dissertation is organized into three major sections representing specific aims to support the GATE implementation of FSI systems. The first aim is to formulate the governing equations for an FSI system and the monolithic finite element formulation to represent the equations numerically. The second aim is to formulate the GATE family of elements and test their performance using manufactured solution methods and test cases with incompressible and compressible flows. Lastly, GATE is used to find solutions to two types of FSI systems. One system is a classical pitching and heaving airfoil model, and the other is a flexible strip trailing a square block benchmark problem
Strategies for combating plant salinity stress: the potential of plant growth-promoting microorganisms.
Global climate change and the decreasing availability of high-quality water lead to an increase in the salinization of agricultural lands. This rising salinity represents a significant abiotic stressor that detrimentally influences plant physiology and gene expression. Consequently, critical processes such as seed germination, growth, development, and yield are adversely affected. Salinity severely impacts crop yields, given that many crop plants are sensitive to salt stress. Plant growth-promoting microorganisms (PGPMs) in the rhizosphere or the rhizoplane of plants are considered the second genome of plants as they contribute significantly to improving the plant growth and fitness of plants under normal conditions and when plants are under stress such as salinity. PGPMs are crucial in assisting plants to navigate the harsh conditions imposed by salt stress. By enhancing water and nutrient absorption, which is often hampered by high salinity, these microorganisms significantly improve plant resilience. They bolster the plants defenses by increasing the production of osmoprotectants and antioxidants, mitigating salt-induced damage. Furthermore, PGPMs supply growth-promoting hormones like auxins and gibberellins and reduce levels of the stress hormone ethylene, fostering healthier plant growth. Importantly, they activate genes responsible for maintaining ion balance, a vital aspect of plant survival in saline environments. This review underscores the multifaceted roles of PGPMs in supporting plant life under salt stress, highlighting their value for agriculture in salt-affected areas and their potential impact on global food security