Functional use of carbon dioxide for the sustainable valorization of orange peel in the pyrolysis process.

Although biomass is carbon-neutral, its use as a primary feedstock faces challenges arising from inconsistent supply chains. Therefore, it becomes crucial to explore alternatives with reliable availability. This study proposes a strategic approach for the thermochemical valorization of food processing waste, which is abundantly generated at single sites within large-scale processing plants. As a model biomass waste from the food industry, orange peel waste was particularly chosen considering its substantial consumption. To impart sustainability to the pyrolysis system, CO2, a key greenhouse gas, was introduced. As such, this study highlights elucidating the functionality of CO2 as a reactive feedstock. Specifically, CO2 has the potential to react with volatile pyrolysates evolved from orange peel waste, leading to CO formation at ≥490 °C. The formation of chemical constituents, encompassing acids, ketones, furans, phenols, and aromatics, simultaneously decreased by 15.1 area% in the presence of CO2. To activate the efficacy of CO2 at the broader temperature spectrum, supplementary measures, such as an additional heating element (700 °C) and a nickel-based catalyst (Ni/Al2O3), were implemented. These configurations promote thermal cracking of the volatiles and their reaction kinetics with CO2, representing an opportunity for enhanced carbon utilization in the form of CO. Finally, the integrated process of CO2-assisted catalytic pyrolysis and water-gas shift reaction was proposed. A potential revenue when maximizing the productivity of H2 was estimated as 2.62 billion USD, equivalent to 1.11 times higher than the results from the inert (N2) environment. Therefore, utilizing CO2 in the pyrolysis system creates a promising approach for enhancing the sustainability of the thermochemical valorization platform while maximizing carbon utilization in the form of CO.

Accurate graph classification via two-staged contrastive curriculum learning.

Given a graph dataset, how can we generate meaningful graph representations that maximize classification accuracy? Learning representative graph embeddings is important for solving various real-world graph-based tasks. Graph contrastive learning aims to learn representations of graphs by capturing the relationship between the original graph and the augmented graph. However, previous contrastive learning methods neither capture semantic information within graphs nor consider both nodes and graphs while learning graph embeddings. We propose TAG (Two-staged contrAstive curriculum learning for Graphs), a two-staged contrastive learning method for graph classification. TAG learns graph representations in two levels: node-level and graph level, by exploiting six degree-based model-agnostic augmentation algorithms. Experiments show that TAG outperforms both unsupervised and supervised methods in classification accuracy, achieving up to 4.08% points and 4.76% points higher than the second-best unsupervised and supervised methods on average, respectively.

Activity-dependent capture of neuropeptide vesicles prepares clock neuron synapses for daily release.

Drosophila brain sLNv clock neurons release the neuropeptide PDF to control circadian rhythms. Strikingly, PDF content in sLNv terminals is rhythmic with a peak in the morning. Peak content drops because of activity-dependent release from dense-core vesicles (DCVs), but the mechanism for the daily increase in presynaptic PDF in the hours prior to release is unknown. Although transport from the soma was proposed to drive the daily increase in presynaptic PDF, live imaging in sLNv neurons shows that anterograde axonal DCV transport is constant throughout the day. Instead, capture of circulating DCVs, indicated by decreased retrograde axonal transport, rhythmically boosts presynaptic neuropeptide content. Genetic manipulations demonstrate that the late night increase in capture requires electrical activity but is independent of daily morphological changes. These results suggest that each day, during the hours of ongoing electrical activity, a toggle switches from inducing vesicle capture to triggering exocytosis, thereby maximizing daily rhythmic bursts of synaptic neuropeptide release by clock neurons.

Exploring Orthopedic Occupational Therapy in Korea: Insights from a Survey on Occupational Therapists' Perspectives.

This study explores the perceptions and experiences of Korean occupational therapists (OTs) about their role in managing elderly patients with orthopedic conditions. The goal is to inform policy discussions for better integration of OT services in orthopedic care settings in Korea. A survey was conducted among Korean clinical OTs to gather data on their perceptions, experiences, and challenges in providing orthopedic OT services. Snowball sampling was used, and the survey addressed general characteristics, orthopedic OT status, perceptions, and competence. The data were analyzed using frequency and percentage calculations in SPSS 22.0. Out of 171 respondents, only 18 had experience working in orthopedic departments, while 78 (45.6%) had provided occupational therapy to orthopedic patients. Rehabilitation medicine physicians were the primary prescribers of orthopedic OT. Key challenges included a lack of awareness among professionals, an absence of appropriate fees, and insufficient knowledge among OTs. The majority of respondents agreed that providing OT in orthopedic departments was appropriate and expressed a need for education and clinical guidelines. The study examines the current state of orthopedic OT in Korea, showing low levels of experience and highlighting challenges, such as a lack of professional awareness, inadequate fees, and insufficient knowledge among OTs. Respondents mostly agreed on the necessity for education and clinical guidelines to improve their capabilities in orthopedic settings. This study emphasizes the need for healthcare system improvements that allow OTs to participate more widely without being confined to specific medical disciplines, promoting a more comprehensive approach to OT, especially as the aging population continues to grow.

Development of Path Generation and Algorithm for Autonomous Combine Harvester Using Dual GPS Antenna.

Research on autonomous driving technology is actively underway to solve the facing problems in the agricultural field. Combine harvesters used in East Asian countries, including Korea, are tracked-type vehicles. The steering control system of the tracked vehicle has different characteristics from the wheeled vehicle used in the agricultural tractor. In this paper, a dual GPS antenna-based autonomous driving system and path tracking algorithm were developed for a robot combine harvester. An α-turn-type work path generation algorithm and a path tracking algorithm were developed. The developed system and algorithm were verified through experiments using actual combine harvesters. The experiment consisted of an experiment with harvesting work and an experiment without harvesting work. In the experiment without harvesting work, an error of 0.052 m occurred during working driving and 0.207 m during turning driving. In the experiment where the harvesting work was carried out, an error of 0.038 m occurred during work driving and 0.195 m during turning driving. As a result of comparing the non-work area and driving time to the results of manual driving, the self-driving experiment with harvesting work showed an efficiency of 76.7%.

Effects of cooling glove on the human body's recovery after exercise and improvement of exercise ability.

BACKGROUND: After high-intensity exercises, the body's core temperature increases, affecting the body's metabolism, increasing thermal stress and muscle fatigue. The most popular technique to maximize post-workout recovery is cryotherapy. However, the cooling effect may vary depending on the body part being cooled since body tissues do not process the same perfusion. OBJECTIVE: This study investigates the effects of hand cooling on human body functional recovery and exercise ability improvement by comparing normal rest and rest with hand cooling gloves after high-intensity exercise. METHODS: Thirty healthy subjects participated in this study wherein they exercised and used normal rest for one session and hand cooling rest for the next. Blood lactate concentration, heart rate recovery rate, VO2 max measurement, and the degree of recovery of muscle strength, muscular endurance, and muscle fatigue were investigated in both groups to determine the efficacy of hand cooling gloves for postexercise recovery. RESULTS: When hands were cooled after exercise, blood lactate concentration and body temperature significantly decreased, and cardiopulmonary function, muscle strength, and muscular endurance significantly recovered. CONCLUSION: Using hand cooling gloves after exercise could attenuate core temperature elevation and improve postexercise recovery. It could also effectively improve athletic performance without using large-scale facilities.

Multivariable Technique for the Evaluation of the Trans-stenotic Pressure Gradient.

PURPOSE: This study establishes a reliable image-based multivariable technique for measuring the trans-stenotic pressure gradient. METHODS: A self-made in vitro steady flow model based on adjustable velocities and stenotic properties were used as the experimental subject. The pre-stenotic flow velocity, severity, and length of the stenosis were used as the input variables. Based on equations used to fit the plots of the physically measured pressure gradient values versus each input variable, a multivariable formula for the pressure gradient measurement could then be derived. The flow model was scanned using velocity-encoded phase-contrast magnetic resonance imaging (PC-MRI) to validate the derived formula while simultaneously measuring the trans-stenotic pressure gradient. The correlation between the physically-measured pressure gradient values and the pressure gradient values calculated using the new formula were subsequently analyzed. RESULTS: The results of linear regression analysis using the physically measured pressure gradient values for the new method were compared to values obtained using the simplified Bernoulli equation (R2, 0.991, and 0.975, respectively). In a paired t-test, no statistically significant difference was found between the new method and the physical measurements. CONCLUSIONS: The derived multivariable technique was found to reliably measure the trans-stenotic pressure gradient, with better performance than a traditional procedure based on the simplified Bernoulli equation.

Recessed-Channel WSe2 Field-Effect Transistor via Self-Terminated Doping and Layer-by-Layer Etching.

Effective channel control with low contact resistance can be accomplished through selective ion implantation in Si and III-V semiconductor technologies; however, this approach cannot be adopted for ultrathin van der Waals materials. Herein, we demonstrate a self-aligned fabrication process based on self-terminated p-doping and layer-by-layer chemical etching to achieve low contact resistance as well as a high on/off current ratio in ultrathin tungsten diselenide (WSe2) field-effect transistors (FETs). Damage-free layer-by-layer thinning of the WSe2 channel is repeated up to a thickness of approximately 1.4 nm, while maintaining the selectively p-doped source/drain regions. The device characteristics of the recessed-channel WSe2 FET are systematically monitored during this layer-by-layer recess-channel process. The WSe2 etching rate is estimated to be 2-3 layers per cycle of oxidation and subsequent chemical etching. The self-terminated tungsten oxide (WOX) layer grown through ultraviolet-ozone treatment induces robust p-doping in the neighboring (or underlying) WSe2 through the electron withdrawal mechanism, which remains in the source/drain regions after channel oxide removal. The adopted self-terminated and self-aligned recess-channel process for ultrathin WSe2 FETs enables the realization of a high on/off output current ratio (>108) and field-effect mobility (∼190 cm2/V·s), while maintaining low contact resistance (0.9-6.1 kΩ·µm) without a postannealing process. The proposed facile and reproducible doping and atomic-layer-etching method for the fabrication of a recessed-channel FET with an ultrathin body can be helpful for high-performance two-dimensional semiconductor devices and is applicable to post-Si complementary metal-oxide semiconductor devices.

Structure-based molecular characterization of the YetL transcription factor from Bacillus subtilis.

Bacillus subtilis is a gram-positive bacterium that has developed to coordinate gene expression and to survive against changes of nutrients and toxic chemicals. Flavonoids are exuded by plant cells and are abundant in the soil. To counteract the antibacterial effects of flavonoids, B. subtilis expresses flavonoid-detoxifying enzymes, and their expression is negatively regulated by transcription factors, including YetL. YetL was shown to control B. subtilis growth through the promoter regions of yetL and yetM genes in response to some flavonoids. Despite the functional significance of the YetL transcription factor in bacterial survival, no structural information is available for YetL. Here, we report the crystal structure of YetL and propose a flavonoid-induced regulatory mechanism. The YetL structure contains the canonical winged helix-turn-helix motif of the MarR superfamily but distinctly presents an additional N-terminal helix. In the dimeric assembly of YetL, the H1 helix intersects the YetL dimer and contributes to extensive intersubunit interactions. As a transcription factor, YetL recognizes a 28-mer operator of double-stranded DNA that contains a palindromic sequence. Moreover, our comparative structural analysis of YetL and other MarR members allows us to propose a flavonoid-induced transcription regulatory mechanism that is used for bacterial adaptation to environmental changes and stresses.

Valorizing plastic toy wastes to flammable gases through CO2-mediated pyrolysis with a Co-based catalyst.

Toys are discarded due to their short life cycle. Unfortunately, development of sustainable disposal platform for toy has not gained particular concern. To establish a reliable disposal platform, this study employed a pyrolysis platform to valorize plastics into value-added fuels. To confer more environmentally resilient process, CO2 was used as a feedstock to enhance the process efficiency from a perspective of the yield of flammable gases. To this end, waste toy brick (WTB) was used as a model compound. The exact types of plastics (polyacrylonitrile, polybutadiene, polystyrene, and polymethyl methacrylate) in WTB were experimentally determined. In pyrolysis of WTB, the complicated mixture of benzene derivatives was inevitably generated. To detoxify them by means of syngas (H2/CO) production, catalytic pyrolysis was performed. Co catalyst effectively induced chemical bond scissions, leading to substantially enhanced H2 formation. Also, the gas phase reactions (GPRs) between CO2 and volatile compounds over Co catalyst expedited the production rate of CO, and such CO enhancement effectively offered a chance to mitigate toxic chemical generations. The synergistic contribution of CO2 and Co catalyst enhanced syngas formation more than 25 times in reference to pyrolysis of WTB without Co catalyst. The GPRs also greatly prevented catalyst deactivation.

Structure-based molecular characterization of the LltR transcription factor from Listeria monocytogenes.

Listeria monocytogenes is a psychrotrophic food-borne pathogenic bacterium that causes listeriosis. Due to its unusual adaptation, an ability to grow at extended temperatures ranging from 4 to 45 °C, L. monocytogenes is notoriously hard to control in food-manufacturing processes. In addition, the growing number of antibiotic-resistant L. monocytogenes strains have made listeriosis steadily refractory to clinical treatments and can lead to serious life-threatening diseases, such as sepsis and meningitis, in immunocompromised persons and neonates. Transcription factors that belong to the PadR family play a key role in bacterial survival against unfavorable environmental stresses. The LltR protein from L. monocytogenes was identified as a PadR-type transcription factor and was shown to be required for bacterial growth adaptation at low temperatures. Despite the functional significance of LltR in listeria survival and pathogenesis, our molecular understanding of the LltR-mediated transcriptional regulation is highly limited. Here, we report the crystal structure of LltR and reveal the operator DNA recognition mechanism used by LltR. LltR dimerizes into an isosceles triangle-like shape and requires a winged helix-turn-helix motif for dsDNA recognition. Indeed, LltR and putative operator dsDNA binding was observed and suggests a transcriptional repression of the llfR-lmo0600-lmo0601 operon by direct interaction between the LltR transcription factor and its promoter region. Structure-based comparative and mutational analyses showed that LltR interacts with dsDNA via a unique strategy that combines both LltR-specific and PadR family-common mechanisms.

Post-processing calcium subtraction method to minimize stenosis-overestimation by blooming artifact.

BACKGROUND: CT images are often affected by blooming artifacts during the diagnosis that facilitate an overestimation of the expression of calcification stenosis, thereby impeding the accurate diagnosis of this condition. OBJECTIVE: Arterial calcification can act as a blooming artifact in computed tomography (CT) images, leading to overestimations of the blood vessel and the size of calcified plaque. This study proposes an improved CT post-processing method that accurately measures calcium and lumen size in blood vessels. METHODS: Six hundred and thirty calcium datasets were obtained from 63 patients diagnosed with a vascular disease. Patients were grouped into three sets corresponding to each image acquisition method used: G1, for the invasive coronary angiography (ICA); G2, for multiplanar reconstruction (MPR) imaging and post-processing; and G3, for the novel method of mixed Gaussian filter and K-mean clustering (GK). Results of GK were generated by adding Gaussian and k-mean clustering algorithms to the MPR post-processing procedure. The analysis of variance (ANOVA), linear regression, and intraclass correlation coefficient (ICC) were used to compare the accuracy and sensitivity of the different methods. All measurements were performed multiple times to mitigate human error. RESULTS: The ANOVA test revealed no significant differences between the G1 and G3 groups. Hence, linear regression was used to analyze the correlation between the G1 and G3 groups (p< 0.05, R2 = 0.885), and a higher correlation than G1 and G2 was reported (p> 0.05, R2 = 0.432). ICC was performed for reproducibility, wherein high correlation was identified among all groups. CONCLUSIONS: Results of the study indicate that the GK method yields images that are very similar to ICA image measurements. This suggests that the GK can be used as a more effective post-processing method over the inaccurate MPR while remaining non-intrusive when determining the arterial stenosis degree, unlike the ICA.

Hemodynamics in a three-dimensional printed aortic model: a comparison of four-dimensional phase-contrast magnetic resonance and image-based computational fluid dynamics.

OBJECTIVE: This study aims to compare an electrocardiogram (ECG)-gated four-dimensional (4D) phase-contrast (PC) magnetic resonance imaging (MRI) technique and computational fluid dynamics (CFD) using variables controlled in a laboratory environment to minimize bias factors. MATERIALS AND METHODS: Data from 4D PC-MRI were compared with computational fluid dynamics using steady and pulsatile flows at various inlet velocities. Anatomically realistic models for a normal aorta, a penetrating atherosclerotic ulcer, and an abdominal aortic aneurysm were constructed using a three-dimensional printer. RESULTS: For the normal aorta model, the errors in the peak and the average velocities were within 5%. The peak velocities of the penetrating atherosclerotic ulcer and the abdominal aortic aneurysm models displayed a more extensive range of differences because of the high-speed and vortical fluid flows generated by the shape of the blood vessel. However, the average velocities revealed only relatively minor differences. CONCLUSIONS: This study compared the characteristics of PC-MRI and CFD through a phantom study that only included controllable experimental parameters. Based on these results, 4D PC-MRI and CFD are powerful tools for analyzing blood flow patterns in vivo. However, there is room for future developments to improve velocity measurement accuracy.

Valorization of carbon dioxide and waste (Derived from the site of Eutrophication) into syngas using a catalytic thermo-chemical platform.

Global warming increases a chance of eutrophication, and such fact offers that unhygienic organic waste materials (OWMs) in water must be treated. Hence, this study laid emphasis on the thermal-chemical (pyrolysis) process to establish a rapid valorization platform for OWMs. Indeed, OWMs were collected from the eutrophication site, and OWMs were mainly comprised of lignocellulosic biomass, microalgae (cyanobacteria) and the diverse types of bacteria (commonly observed from livestock waste). In an attempt to offer more sustainable valorization route for OWMs, CO2 was used as a raw material in pyrolysis process. From the CO2-assisted pyrolysis, the conversion of CO2 and OWMs into gaseous fuel (CO) was observed. A cheap Ni-based catalyst was used in pyrolysis of OWMs as a strategic practice to promote conversion of CO2 into CO. Indeed, syngas production (38 %) was enhanced from catalytic pyrolysis over Ni/SiO2 under CO2 condition as compared to inert condition (N2).

Compressing deep graph convolution network with multi-staged knowledge distillation.

Given a trained deep graph convolution network (GCN), how can we effectively compress it into a compact network without significant loss of accuracy? Compressing a trained deep GCN into a compact GCN is of great importance for implementing the model to environments such as mobile or embedded systems, which have limited computing resources. However, previous works for compressing deep GCNs do not consider the multi-hop aggregation of the deep GCNs, though it is the main purpose for their multiple GCN layers. In this work, we propose MustaD (Multi-staged knowledge Distillation), a novel approach for compressing deep GCNs to single-layered GCNs through multi-staged knowledge distillation (KD). MustaD distills the knowledge of 1) the aggregation from multiple GCN layers as well as 2) task prediction while preserving the multi-hop feature aggregation of deep GCNs by a single effective layer. Extensive experiments on four real-world datasets show that MustaD provides the state-of-the-art performance compared to other KD based methods. Specifically, MustaD presents up to 4.21%p improvement of accuracy compared to the second-best KD models.

3D print material study to reproduce the function of pig heart tissue.

BACKGROUND: Three-dimensional (3D) printing technology for heart simulation can be represented as complex anatomical structures, and objective information can be provided. OBJECTIVE: We studied 3D print material to find a material with the same elastic coefficient as pig elastic coefficient. METHODS: Pig heart sample, Agilus sample, Tango sample, TPU sample, and silicone sample were studied. The elastic coefficient of each specimen was measured using an elastic coefficient measuring instrument. The analysis was performed using the average value of ten specimens of the same size. We suggested an equation to find the elastic coefficient of material by the thickness using the elastic coefficient of Agilus, Tango, and silicone. RESULTS: The sample with similar elasticity to the pig sample did not show the same coefficient of elasticity at the same sample size. In Tango, the 0.5 mm high elastic force was about 3 times higher than the pig sample 7 mm elastic force. CONCLUSIONS: The study was conducted using 3D print material and silicone which can reproduce the elasticity of pig heart. However, no material is currently available to reproduce pig heart sample of the same size. However, if the heart is developed considering only elasticity, it can be sufficiently reproduced using the research results.

Enhancement of sophorolipids production in Candida batistae, an unexplored sophorolipids producer, by fed-batch fermentation.

Sophorolipids (SLs) from Candida batistae has a unique structure that contains ω-hydroxy fatty acids, which can be used as a building block in the polymer and fragrance industries. To improve the production of this industrially important SLs, we optimized the culture medium of C. batistae for the first time. Using an optimized culture medium composed of 50 g/L glucose, 50 g/L rapeseed oil, 5 g/L ammonium nitrate and 5 g/L yeast extract, SLs were produced at a concentration of 24.1 g/L in a flask culture. Sophorolipids production increased by about 19% (28.6 g/L) in a fed-batch fermentation using a 5 L fermentor. Sophorolipids production more increased by about 121% (53.2 g/L), compared with that in a flask culture, in a fed-batch fermentation using a 50 L fermentor, which was about 787% higher than that of the previously reported SLs production (6 g/L). These results indicate that a significant increase in C. batistae-derived SLs production can be achieved by optimization of the culture medium composition and fed-batch fermentation. Finally, we successfully separated and purified the SLs from the culture medium. The improved production of SLs from C. batistae in this study will help facilitate the successful development of applications for the SLs.

Comparative study on carbon dioxide-cofed catalytic pyrolysis of grass and woody biomass.

This study investigated the mechanistic functions of CO2 on the pyrolysis of two different biomasses to elucidate the effect of CO2 on syngas formations during pyrolysis. To this end, CO2-assisted pyrolysis of cellulosic biomass (barnyard grass, Echinochloa) and lignin-rich woody biomass (retinispora, Chamaecyparis obtusa) were compared. The confirmed mechanistic effectiveness of CO2 on pyrolysis of biomass was gas phase reactions between CO2 and volatile matters from biomass pyrolysis. Lignin-rich biomass had more CO2 susceptibility, resulting in more enhanced CO formation via the gas phase reactions. To expedite the slow reaction rate of the gas phase reactions during biomass pyrolysis, earth-abundant catalysts (Co/SiO2 and Ni/SiO2) were employed for pyrolysis of two biomass substrates. With Co and Ni catalysts, the syngas formations were 2 and 3 times higher comparing to the pyrolysis of without catalyst. The cumulative formations of syngas from lignin-rich biomass was nearly doubled than that from cellulosic biomass.

Non-inferiority study of the efficacy of two hyaluronic acid products in post-extraction sockets of impacted third molars.

BACKGROUND: Hyaluronic acid (HA) is well known to exert an anti-inflammatory effect during oral wound healing and is commonly applied after tooth extraction. However, no double-blind randomized controlled study comparing two hyaluronate mouthwash products has been conducted so far. The aim of this study was to comparatively analyze the efficacy of Mucobarrier® and Aloclair® in terms of clinical symptoms. RESULTS: A total of 112 patients were randomly assigned to assess the degree of discomfort, pain reduction, redness, burning sensation, and swelling between two groups on the day of surgery and 7 days later in a double blind test, with a total 56 Aloclair patients and 56 Mucobarrier patients. There was no statistically significant difference in the overall discomfort, degree of pain reduction, redness, burning sensation, and swelling between the Mucobarrier and Aloclair groups. CONCLUSION: The local application of hyaluronic acid mouth wash after wisdom tooth extraction is beneficial in reducing overall discomfort and pain reduction, and the clinical utility of Mucobarrier® is no different from Aloclair®. TRIAL REGISTRATION: Institutional Review Board of Yonsei University College of Dentistry, 2-2018-0036. Registered 10 September 2018-prospectively registered, https://eirb.yuhs.ac/.