Publications by authors named "Jeong-Seop Lee"

Article Synopsis
  • Microalgae are a promising and sustainable biomass resource, but research on large-scale harvesting processes is limited despite available technologies.
  • A new harvesting system has been developed that combines dissolved air flotation and screw-press filtration, resulting in lower energy consumption and high biomass harvest efficiency (93%) for chlorella sp.
  • This system is more energy-efficient than traditional centrifugation methods, using 60.5% less energy, and demonstrates strong potential for scaling up microalgae biomass harvesting for industrial use.
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The extraction of astaxanthin from Haematococcus pluvialis involves the utilization of petroleum-derived organic solvents or supercritical CO, beset by safety concerns, high costs, and environmental sustainability limitations. This study, in contrast, employed a method involving the adjustment of salt concentration, propylene glycol, and vegetable oil fraction to disrupt emulsion in aqueous cell lysates for facilitating the separation of astaxanthin. Under optimized conditions, an astaxanthin-containing oil with a content of 1.

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Article Synopsis
  • A new biosensor using a single plasmonic asymmetric nanobridge (PAN) has been developed to differentiate between mild cognitive impairment (MCI) and Alzheimer's disease (AD) by analyzing phosphorylated tau proteins (p-tau) in blood samples.
  • The PAN biosensor features a unique design that enhances sensitivity, allowing it to detect very low levels of p-tau, which is closely related to the progression of AD.
  • By incorporating machine learning techniques, the diagnostic system achieves a high accuracy rate of 94.47% in predicting health status among individuals, indicating its potential for early detection of Alzheimer's disease.
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Autism spectrum disorder (ASD) is a heterogeneous developmental disorder characterized by impairments in two core areas: 1) social communication and interaction and 2) restricted and repetitive patterns of behaviors and interests. In general, ASD is known to be a lifelong disorder. Follow-up studies from childhood to adulthood have reported that the severity of the key symptoms ASD decreases over time.

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Bioplastic production using cyanobacteria can be an effective strategy to cope with environmental problems caused by using petroleum-based plastics. Synechococcus elongatus UTEX 2973 with heterogeneous phaCAB can produce bioplastic polyhydroxybutyrate (PHB) with a high CO uptake rate. For cost-effective production of PHB in S.

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Wastewater treatment plants are indispensable facilities, which emit a massive amount of greenhouse gases. To boost CO mitigation and wastewater treatment performance, mixotrophic microalgae cultivation using wastewater has recently been proposed. In this study, food industry wastewater (waste soy sauce) was applied to Chlorella sorokiniana UTEX 2714 cultivation.

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Photosynthetic polyhydroxybutyrate (PHB) production is an attractive technology for realizing a sustainable society by simultaneously producing useful biodegradable plastics and mitigating CO. It is necessary to establish an economical large-scale photobioreactor (PBR) capable of effectively cultivating photosynthetic microorganisms such as cyanobacteria. A roll-to-roll winding machine/heat-sealer hybrid system for fabricating an easy-to-scale-up PBR was developed in the present study.

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Objectives: This study aimed to compare the quality of life (QoL) of children with attention-deficit/hyperactivity disorder (ADHD) before and during coronavirus disease-2019 (COVID-19) and to examine how their QoL is affected by emotional and environmental factors during COVID-19.

Methods: Participants in the pre-COVID-19 (n=43) and COVID-19 (n=36) groups were recruited from the same university hospital. The Pediatric Quality of Life Inventory (PedsQL) 4.

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The microalgae-based bioconversion process is a promising carbon utilization technology because it can upgrade CO into valuable substances, but a multiplex monitoring system required for process control to maximize biomass productivity has not been well established. Herein, a 3D printed real-time optical density monitoring device (RTOMD) combined platform was presented. This platform enables precise kinetics analysis by maintaining high accuracy (over 95 %) under raucous outdoor conditions.

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Due to industrialization and rapid increase in world population, the global energy consumption has increased dramatically. As a consequence, there is increased consumption of fossil fuels, leading to a rapid increase in CO concentration in the atmosphere. This accumulated CO can be efficiently used by autotrophs as a carbon source to produce chemicals and biopolymers.

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The microalgae Haematococcus pluvialis biologically converts CO into natural astaxanthin that possesses a strong antioxidant activity; its low carbon footprint and economic viability have allowed it to garner great attention. However, low efficiency of the cultivation process is a major hurdle in its commercial production. Here, additional nitrogen was provided to fully grown cells to induce efficient cyst germination, thereby rapidly increasing the number of cells containing astaxanthin.

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Plasmonic coupling of metallic nanostructures with two-dimensional molybdenum disulfide (MoS2) atomic layers is an important topic because it provides a pathway to manipulate the optoelectronic properties and to overcome the limited optical cross-section of the materials. Plasmonic enhanced light-matter interaction of a MoS2 layer is known to be mainly governed by optical field enhancement and the Purcell effect, while the discrimination of the contribution from each mechanism to the plasmonic enhancement is challenging. Here, we investigate photoluminescence (PL) enhancement from few-layer MoS2 transferred on Au nanostructure arrays with controlled localized surface plasmon resonance (LSPR) spectral positions that were detuned from the excitation wavelengths.

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Fabrication of plasmonic nanostructures in a precise and reliable manner is a topic of huge interest because their structural details significantly affect their plasmonic properties. Herein, we present nanotip indentation lithography (NTIL) based on atomic force microscopy (AFM) indentation for the patterning of plasmonic nanostructures with precisely controlled size and shape. The size of the nanostructures is controlled by varying the indentation force of AFM tips into the mask polymer; while their shapes are determined to be nanodisks (NDs) or nanotriangles (NTs) depending on the shapes of the AFM tip apex.

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Industrial application of cyanobacterial poly-β-hydroxybutyrate (PHB) production from CO is currently challenged by slow growth rate and low photoautotrophic PHB productivity of existing cyanobacteria species. Herein, a novel PHB-producing cyanobacterial strain was developed by harnessing fast-growing cyanobacteria Synechococcus elongatus UTEX 2973 with introduction of heterologous phaCAB genes. Under photoautotrophic condition, the engineered strain produced 420 mg L (16.

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Background: KBG syndrome (OMIM #148050) is a rare, autosomal dominant inherited genetic disorder caused by heterozygous mutations in the ankyrin repeat domain-containing protein 11 (ANKRD11) gene or by microdeletion of chromosome 16q24.3. It is characterized by macrodontia of the upper central incisors, distinctive facial dysmorphism, short stature, vertebral abnormalities, hand anomaly including clinodactyly, and various degrees of developmental delay.

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Economically feasible photosynthetic cultivation of microalgal and cyanobacterial strains is crucial for the biological conversion of CO and potential CO mitigation to challenge global warming. To overcome the economic barriers, the production of value-added chemicals was desired by compensating for the overall processing cost. Here, we engineered cyanobacteria for photosynthetic squalene production and cultivated them in a scalable photobioreactor using industrial flue gas.

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Microalgae have a high potential to be utilized as feedstock for biofuels because they have high growth rates and do not compromise food production. Commercialized algae-based biofuel production relies on the development of strains with high lipid content. Based on the relatively low density of lipids compared to other cellular components, density gradient centrifugation was used to isolate high lipid content algal strains from Chlamydomonas reinhardtii mutant libraries.

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Objectives: This study aimed to compare the quality of life reported by patients with attention-deficit/hyperactivity disorder (ADHD) to the patients' quality of life as reported by their caregivers. In addition, it aimed to examine how emotional problems, including depression and anxiety, and the severity of the symptoms affect the quality of life reported by the patients and their caregivers.

Methods: The patients' quality of life and their degree of depression and anxiety were measured using the Pediatric Quality of Life Inventory (PedsQL) 4.

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Direct combustion of biomass is considered the most effective and simple means to contribute to CO reduction. In this context, the life-cycle potential of microalgal solid fuel, which has been overlooked so far, was comprehensively scrutinized ranging from cultivation to direct combustion. According to the quantitative data, using the raw fuel was confirmed to offer great benefits over the conventional lipid-targeted microalgal fuel systems through exploiting all of the biomass' energy potential, thereby being able to significantly increase the energy yield from biomass.

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Microalgae have been rising as a feedstock for biofuel in response to the energy crisis. Due to a high lipid content, composed of fatty acids favorable for the biodiesel production, microalgae are still being investigated as an alternative to biodiesel. Environmental factors and process conditions can alternate the quality and the quantity of lipid produced by microalgae, which can be critical for the overall production of biodiesel.

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We report the nonresonant plasmonic terahertz (THz) wave detector based on the silicon (Si) field effect transistor (FET) with a technology computer-aided design (TCAD) platform. The plasma wave behavior has been modeled by a quasi-plasma electron box as a two-dimensional electron gas (2DEG) in the channel of the FET. The incoming alternating current (AC) signal as the THz wave radiation can induce the direct-current (DC) voltage difference between the source and drain, which is called the photoresponse.

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Purpose: The purpose of this study was to identify and understand nurses' experiences of the death of patients in geriatric hospitals.

Methods: Van Manen's hermeneutic phenomenological analysis was applied in the interpretation of experiential descriptions of seven nurses who had experienced the death of patients in a geriatric hospital.

Results: The essential subjects derived from the experience of the nurses on the death of patients in a geriatric hospital are covered in the following 7 themes.

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