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This study presents the nutrition survey methods and the updated food composition database for the Korean Genome and Epidemiology Study (KoGES). The KoGES, which is the largest and longest cohort study in Korea, aims to identify genetic and environmental factors associated with chronic diseases. This study has collected dietary data using a validated semi-quantitative food frequency questionnaire and/or the 24-hour recall method. However, these dietary survey methods use different food composition databases, and their nutritional values are out of date. Therefore, it became necessary to update the food composition database by revising nutrient analysis values to reflect improvements in the performance of food ingredient analysis equipment, revising international values to analysis values of Korean agricultural products, adjusting nutrient units, and adding newly reported nutrients related to chronic diseases. For this purpose, we integrated the different food composition databases used in each nutrition survey, updated 23 nutrients, and expanded 48 new nutrients for 3,648 food items using the latest reliable food composition databases published by national and international institutions. This revised food composition database may help to clarify the relationship between various nutrients and chronic diseases. It could serve as a valuable resource for nutritional, epidemiological, and genomic research and provide a basis for determining public health policies.
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Bases de données factuelles , Enquêtes nutritionnelles , Humains , République de Corée/épidémiologie , Études de cohortesRÉSUMÉ
OBJECTIVES: Late mealtime and short sleep are known to be associated with obesity risk due to a misaligned circadian rhythm. This study aimed to investigate the relationship between obesity and mealtime and sleep duration using the Korean Genome and Epidemiology Study (KoGES) data. DESIGN: Longitudinally prospective cohort study. SETTING: Population-based. PARTICIPANTS: KoGES analysed data from 9,474 Korean adults with an average age of 54- years old at baseline. MEASUREMENTS: Meal timing was defined as the eating occasions of the day reported by the participant eating a 24-h dietary recall method. Sleep duration was categorized as <6, 6-7, 7-8, and ≥8 h. The Cox proportional hazard model was used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for incident obesity according to meal timing, sleep duration, and nightly fasting duration. RESULTS: During a mean follow-up of 3.5 years, 826 participants developed obesity. In the multivariable-adjusted analysis, midnight snack eating (HR, 1.20; 95% CI, 1.02-1.41) and higher energy intake from midnight snacks (HR, 1.26; 95% CI, 1.06-1.49) were associated with a higher risk of obesity. Sleeping 8 h or more (HR, 0.67; 95% CI, 0.53-0.85) was associated with a lower risk of obesity. CONCLUSIONS: Our findings highlight the importance of meal and sleep times and suggest that healthy eating habits related to the time of day.
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Ration calorique , Repas , Obésité , Sommeil , Humains , Adulte d'âge moyen , Mâle , Femelle , Études prospectives , Sommeil/physiologie , Obésité/épidémiologie , Incidence , République de Corée/épidémiologie , Études longitudinales , Facteurs temps , Modèles des risques proportionnels , Facteurs de risque , Comportement alimentaire , Casse-croute , Rythme circadien/physiologie , Jeûne , Temps de sommeilRÉSUMÉ
BACKGROUND: Air pollution-induced systemic inflammation and oxidative stress are hypothesized to be the major biological mechanisms underlying pathological outcomes. We examined the association between short-term exposure to ambient air pollutants and biomarkers of inflammation and oxidative stress in 2199 general middle-aged Korean population residing in metropolitan areas. METHODS: Serum levels of inflammatory cytokines (interleukin [IL]-1ß, IL-6, IL-8, IL-10, and tumor necrosis factor [TNF]-α) and urinary levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG) were measured. Daily concentrations of a series of air pollutants (particulate matter [PM]10, PM2.5, SO2, NO2, CO, and O3) were predicted using the Community Multiscale Air Quality modeling system, and participant-level pollutant exposure was determined using geocoded residential addresses. Short-term exposure was defined as the 1- to 7-day moving averages. RESULTS: The multivariable-adjusted linear models controlling for the sociodemographic, lifestyle, temporal, and meteorological factors identified positive associations of PM with IL-1ß, IL-8, IL-10, TNF-α, and 8-OHdG levels; SO2 with IL-10 levels, CO with IL-1ß, IL-10, and TNF-α levels; and O3 with IL-1ß, IL-8, and 8-OHdG levels. O3 levels were inversely associated with IL-10 levels. For each pollutant, the strongest associations were observed for the 7-day average PM and CO with IL-1ß (per 10-µg/m3 increase in PM10: 2.7%, 95% confidence interval [CI] = 0.6-4.8; per 10-µg/m3 increase in PM2.5: 6.4%, 95% CI = 2.4-10.5; per 0.1-ppm increase in CO: 3.3%, 95% CI = 0.3-6.5); the 2-day average SO2 with IL-10 levels (per 1-ppb increase in SO2: 1.1%, 95% CI = 0.1-2.1); and the 7-day average O3 with IL-8 levels (per 1-ppb increase in O3: 1.3%, 95% CI = 0.7-1.9). CONCLUSIONS: Short-term exposure to ambient air pollutants may induce oxidative damage and pro-inflammatory roles, together with counter-regulatory anti-inflammatory response.
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Polluants atmosphériques , Polluants environnementaux , Adulte d'âge moyen , Humains , Polluants atmosphériques/effets indésirables , Polluants atmosphériques/analyse , Études transversales , Interleukine-10 , Interleukine-8 , Facteur de nécrose tumorale alpha , Matière particulaire/effets indésirables , Matière particulaire/analyse , Inflammation/induit chimiquement , Inflammation/épidémiologie , Marqueurs biologiques , Stress oxydatifRÉSUMÉ
BACKGRUOUND: To investigate the association between the time-varying resting heart rate (RHR) and change in RHR (∆RHR) over time and the risk of diabetes mellitus (DM) by sex. METHODS: We assessed 8,392 participants without DM or atrial fibrillation/flutter from the Korean Genome and Epidemiology Study, a community-based prospective cohort study that was initiated in 2001 to 2002. The participants were followed up until December 31, 2018. Updating RHR with biennial in-study re-examinations, the time-varying ∆RHR was calculated by assessing the ∆RHR at the next follow-up visit. RESULTS: Over a median follow-up of 12.3 years, 1,345 participants (16.2%) had DM. As compared with RHR of 60 to 69 bpm, for RHR of ≥80 bpm, the incidence of DM was significantly increased for both male and female. A drop of ≥5 bpm in ∆RHR when compared with the stable ∆RHR group (-5< ∆RHR <5 bpm) was associated significantly with lower risk of DM in both male and female. However, an increase of ≥5 bpm in ∆RHR was significantly associated with higher risk of DM only in female, not in male (hazard ratio for male, 1.057 [95% confidence interval, 0.869 to 1.285]; and for female, 1.218 [95% confidence interval, 1.008 to 1.471]). CONCLUSION: In this community-based longitudinal cohort study, a reduction in ∆RHR was associated with a decreased risk of DM, while an increase in ∆RHR was associated with an increased risk of DM only in female.
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Diabète , Rythme cardiaque , Humains , Mâle , Femelle , Adulte d'âge moyen , Rythme cardiaque/physiologie , Études prospectives , Facteurs de risque , République de Corée/épidémiologie , Diabète/épidémiologie , Incidence , Adulte , Sujet âgé , Facteurs sexuels , Études de suivi , Repos/physiologie , Facteurs tempsRÉSUMÉ
Many quantum dot light-emitting diodes (QLEDs) utilize ZnO nanoparticles (NPs) as an electron injection layer (EIL). However, the use of the ZnO NP EIL material often results in a charge imbalance within the quantum dot (QD) emitting layer (EML) and exciton quenching at the interface of the QD EML and ZnO NP EIL. To overcome these challenges, we introduced an arginine (Arg) interlayer (IL) onto the ZnO NP EIL. The Arg IL elevated the work function of ZnO NPs, thereby suppressing electron injection into the QD, leading to an improved charge balance within the QDs. Additionally, the inherent insulating nature of the Arg IL prevented direct contact between QDs and ZnO NPs, reducing exciton quenching and consequently improving device efficiency. An inverted QLED (IQLED) utilizing a 20 nm-thick Arg IL on the ZnO NP EIL exhibited a 2.22-fold increase in current efficiency and a 2.28-fold increase in external quantum efficiency (EQE) compared to an IQLED without an IL. Likewise, the IQLED with a 20 nm-thick Arg IL on the ZnO NP EIL demonstrated a 1.34-fold improvement in current efficiency and a 1.36-fold increase in EQE compared to the IQLED with a 5 nm-thick polyethylenimine IL on ZnO NPs.
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BACKGROUND: Collagen is a key component of connective tissue and has been frequently used in the fabrication of medical devices for tissue regeneration. Human-originated collagen is particularly appealing due to its low immune response as an allograft biomaterial compared to xenografts and its ability to accelerate the regeneration process. Ethically and economically, adipose tissues available from liposuction clinics are a good resource to obtain human collagen. However, studies are still scarce on the extraction and characterization of human collagen, which originates from adipose tissue. The aim of this study is to establish a novel and simple method to extract collagen from human adipose tissue, characterize the collagen, and compare it with commercial-grade porcine collagen for tissue engineering applications. METHODS: We developed a method to extract the collagen from human adipose tissue under quasi-Good Manufacturing Practice (GMP) conditions, including freezing the tissue, blood removal, and ethanol-based purification. Various techniques, including protein quantification, decellularization assessment, SDS-PAGE, FTIR, and CD spectroscopy analysis, were used for characterization. Amino acid composition was compared with commercial collagen. Biocompatibility and cell proliferation tests were performed, and in vitro tests using collagen sponge scaffolds were conducted with statistical analysis. RESULTS: Our results showed that this human adipose-derived collagen was equivalent in quality to commercially available porcine collagen. In vitro testing demonstrated high cell attachment and the promotion of cell proliferation. CONCLUSION: In conclusion, we developed a simple and novel method to extract and characterize collagen and extracellular matrix from human adipose tissue, offering a potential alternative to animal-derived collagen for xeno-free tissue engineering applications.
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Ingénierie tissulaire , Structures d'échafaudage tissulaires , Suidae , Animaux , Humains , Ingénierie tissulaire/méthodes , Structures d'échafaudage tissulaires/composition chimique , Tissu adipeux/métabolisme , Collagène/composition chimique , Matrice extracellulaireRÉSUMÉ
Demand is increasing for photovoltaics (PVs) as a result of the development of the Internet of Things and edge computing technologies. As the lighting environment is different for the applications, thus, PVs must be adjustable to various light environments in which systems are installed. PVs should therefore be capable of easily changing their morphology without damaging the cells. To address this problem, in this work, a three-dimensional (3D) structure that increases power output under omnidirectional light was applied to a crystalline silicon solar cell array using a block-type method. The resultant block-type 3D indoor PV could operate a Bluetooth low-energy module in conjunction with a power management integrated circuit when the illuminance was 532 lx and 1620 lx and each PV installation area was 129.9cm2 and 32.48 cm2 respectively.
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This paper presents a study that aims to enhance the performance of quantum dot light-emitting didoes (QLEDs) by employing a solution-processed molybdenum oxide (MoOx) nanoparticle (NP) as a hole injection layer (HIL). The study investigates the impact of varying the concentrations of the MoOx NP layer on device characteristics and delves into the underlying mechanisms that contribute to the observed enhancements. Experimental techniques such as an X-ray diffraction and field-emission transmission electron microscopy were employed to confirm the formation of MoOx NPs during the synthesis process. Ultraviolet photoelectron spectroscopy was employed to analyze the electron structure of the QLEDs. Remarkable enhancements in device performance were achieved for the QLED by employing an 8 mg/mL concentration of MoOx nanoparticles. This configuration attains a maximum luminance of 69,240.7 cd/cm2, a maximum current efficiency of 56.0 cd/A, and a maximum external quantum efficiency (EQE) of 13.2%. The obtained results signify notable progress in comparison to those for QLED without HIL, and studies that utilize the widely used poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) HIL. They exhibit a remarkable enhancements of 59.5% and 26.4% in maximum current efficiency, respectively, as well as significant improvements of 42.7% and 20.0% in maximum EQE, respectively. This study opens up new possibilities for the selection of HIL and the fabrication of solution-processed QLEDs, contributing to the potential commercialization of these devices in the future.
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199Three-dimensional (3D) scaffolds composed of various biomaterials, including metals, ceramics, and synthetic polymers, have been widely used to regenerate bone defects. However, these materials possess clear downsides, which prevent bone regeneration. Therefore, composite scaffolds have been developed to compensate these disadvantages and achieve synergetic effects. In this study, a naturally occurring biomineral, FeS2, was incorporated in PCL scaffolds to enhance the mechanical properties, which would in turn influence the biological characteristics. The composite scaffolds consisting of different weight fractions of FeS2 were 3D printed and compared to pure PCL scaffold. The surface roughness (5.77-fold) and the compressive strength (3.38-fold) of the PCL scaffold was remarkably enhanced in a dose-dependent manner. The in vivo results showed that the group with PCL/ FeS2 scaffold implanted had increased neovascularization and bone formation (2.9-fold). These results demonstrated that the FeS2 incorporated PCL scaffold might be an effective bioimplant for bone tissue regeneration.
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Until recent, there are no ideal small diameter vascular grafts available on the market. Most of the commercialized vascular grafts are used for medium to large-sized blood vessels. As a solution, vascular tissue engineering has been introduced and shown promising outcomes. Despite these optimistic results, there are limitations to commercialization. This review will cover the need for extrusion-based 3D cell-printing technique capable of mimicking the natural structure of the blood vessel. First, we will highlight the physiological structure of the blood vessel as well as the requirements for an ideal vascular graft. Then, the essential factors of 3D cell-printing including bioink, and cell-printing system will be discussed. Afterwards, we will mention their applications in the fabrication of tissue engineered vascular grafts. Finally, conclusions and future perspectives will be discussed.
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Ambient air pollutants reportedly increase inflammatory responses associated with multiple chronic diseases. We investigated the effects of long-term exposure to ambient air pollution on high-sensitivity C-reactive protein (hs-CRP) using data from 60,581 participants enrolled in the Korean Genome and Epidemiology Study-Health Examinees Study between 2012 and 2017. Community Multiscale Air Quality System with surface data assimilation was used to estimate the participants' exposure to criteria air pollutants based on geocoded residential addresses. Long-term exposure was defined as the 2-year moving average concentrations of PM10, PM2.5, SO2, NO2, and O3. Multivariable linear and logistic regression models were utilized to estimate the percent changes in hs-CRP and odds ratios of systemic low-grade inflammation (hs-CRP > 3 mg/L) per interquartile range increment in air pollutants. We identified positive associations between hs-CRP and PM10 (% changes: 3.75 [95% CI 2.68, 4.82]), PM2.5 (3.68, [2.57, 4.81]), SO2 (1.79, [1.10, 2.48]), and NO2 (3.31, [2.12, 4.52]), while negative association was demonstrated for O3 (-3.81, [-4.96, -2.65]). Elevated risks of low-grade inflammation were associated with PM10 (odds ratio: 1.07 [95% CI 1.01, 1.13]), PM2.5 (1.08 [1.02, 1.14]), and SO2 (1.05 [1.01, 1.08]). The odds ratios reported indicated that the exposures might be risk factors for inflammatory conditions; however, they did not reflect strong associations. Our findings suggest that exposure to air pollutants may play a role in the inflammation process.
Sujet(s)
Polluants atmosphériques , Pollution de l'air , Polluants environnementaux , Ozone , Polluants atmosphériques/effets indésirables , Polluants atmosphériques/analyse , Pollution de l'air/effets indésirables , Pollution de l'air/analyse , Protéine C-réactive/métabolisme , Études transversales , Poussière , Exposition environnementale/effets indésirables , Exposition environnementale/analyse , Humains , Inflammation/induit chimiquement , Inflammation/épidémiologie , Dioxyde d'azote/analyse , Ozone/effets indésirables , Ozone/analyse , Matière particulaire/effets indésirables , Matière particulaire/analyseRÉSUMÉ
Public concern about the adverse health effects of air pollution has grown rapidly in Korea, and there has been increasing demand for research on ways to minimize the health effects of air pollution. Integrating large epidemiological data and air pollution exposure levels can provide a data infrastructure for studying ambient air pollution and its health effects. The Korean Genome and Epidemiology Study (KoGES), a large population-based study, has been used in many epidemiological studies of chronic diseases. Therefore, KoGES cohort data were linked to air pollution data as a national resource for air pollution studies. Air pollution data were produced using community multiscale air quality modeling with additional adjustment of monitoring data, satellite-derived aerosol optical depth, normalized difference vegetation index, and meteorological data to increase the accuracy and spatial resolution. The modeled air pollution data were linked to the KoGES cohort based on participants' geocoded residential addresses in grids of 1 km (particulate matter) or 9 km (gaseous air pollutants and meteorological variables). As the integrated data become available to all researchers, this resource is expected to serve as a useful infrastructure for research on the health effects of air pollution.
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Polluants atmosphériques , Pollution de l'air , Humains , Pollution de l'air/effets indésirables , Pollution de l'air/analyse , Polluants atmosphériques/effets indésirables , Polluants atmosphériques/analyse , Matière particulaire/effets indésirables , Études épidémiologiques , République de Corée/épidémiologie , Exposition environnementale/effets indésirablesRÉSUMÉ
Exposure to ambient air pollution and its threat to human health is a global concern, especially in the elderly population. Therefore, more in-depth studies are required to understand the extent of the harmful effects of particulate matter (PM) based on duration and levels of exposure. An investigation was conducted to determine the association between short- (1-14 days), medium- (1, 3, and 6 months), and long-term (1, 2, and 3 years) exposure to air pollutants (PM2.5 and PM10) and cognitive function among Koreans (4175 participants, mean age 67.8 years, 55.2% women) aged over 50 years. Higher levels of PM2.5 exposure for short to long term and PM10 exposure for medium to long term were found to be associated with decreased cognitive function, as indicated by lower scores of the Mini-Mental State Examination adopted in Korean (K-MMSE). There were significant effect modifications by sex, age group, alcohol consumption, physical activity, and smoking status in the association between long-term PM2.5 and PM10 exposure and cognitive function. These findings, which underscore the importance of the efforts to reduce the exposure levels and durations of air pollutants, especially in the vulnerable elderly population, provide evidence for establishing more stringent policies for air pollution regulations.
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Polluants atmosphériques , Pollution de l'air , Sujet âgé , Polluants atmosphériques/analyse , Polluants atmosphériques/toxicité , Pollution de l'air/effets indésirables , Pollution de l'air/analyse , Cognition , Exposition environnementale/effets indésirables , Exposition environnementale/analyse , Femelle , Humains , Mâle , Adulte d'âge moyen , Matière particulaire/analyse , Matière particulaire/toxicitéRÉSUMÉ
Prevention strategies for atrial fibrillation (AF) are lacking. This study aimed to identify modifiable risk factors (MRFs) and estimate their impact on AF in the midlife general population. We assessed 9049 participants who were free of prevalent AF at baseline from the Korean Genome and Epidemiology Study. Cox models with time-varying assessment of risk factors were used to identify significant MRFs for incident AF. The MRF burden was defined as the proportion of visits with MRFs during follow-up. Over a median follow-up of 13.1 years, 182 (2.01%) participants developed AF. Three MRFs, including systolic blood pressure (SBP) ≥ 140 mmHg, obesity with central obesity, and an inactive lifestyle were significantly associated with incident AF. Among participants with 3, 2, 1, and 0 MRFs at baseline, 16 (3.9%), 51 (2.5%), 90 (1.8%) and 25 (1.5%) had incident AF, respectively. Compared to participants with three MRFs, those with one or no MRFs had a decreased risk of AF (hazard ratio [95% CI] for one MRF, 0.483 [0.256-0.914]; and for no MRF, 0.291 [0.145-0.583]). A decreasing MRF burden was associated with reduced AF risk (hazard ratio [95% CI] per 10% decrease in burden for SBP ≥ 140 mmHg, 0.937 [0.880-0.997]; for obesity with central obesity, 0.942 [0.907-0.978]; for inactivity, 0.926 [0.882-0.973]). Maintaining or achieving MRF ≤ 1 was associated with decreased AF risk, suggesting that minimizing the burden of MRF might help prevent AF.
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Fibrillation auriculaire , Fibrillation auriculaire/épidémiologie , Humains , Incidence , Obésité/complications , Obésité/épidémiologie , Obésité abdominale , Études prospectives , Facteurs de risqueRÉSUMÉ
Occupational noise is known to be one of the most hazardous risk factors, frequently exceeding the exposure limit thus causing hearing loss and other health outcomes among many field workers in various industries and workplaces. This study aims to characterize the levels of occupational noise exposure during the daily working hours and break periods (sampling preparation and lunch break), identify work-related characteristics affecting the noise exposure levels when including or excluding the break periods and finally determine the most effective approach for occupational noise exposure assessment by using the Korean and U.S. OSHA's guidelines. A total of 1575 workers employed by a large shipbuilding company participated in this study, and the historical exposure datasets of noise dosimeters, collected from 2016 to 2018, were classified by characteristics. A threshold level (TL) for the noise dosimeter was set as a value of 80 dBA during the break periods, including the preparation time for sampling instruments and one hour for the lunch break. The shipbuilding workers were exposed to high levels of occupational noise during the break periods, especially for those working in heating, grinding, and power processes in the painting-related departments. Out of 1575 samples, most cases were related to the preparation time (N = 1432, 90.9%) and lunch break (N = 1359, 86.9%). During the break time, the levels of noise exposure were measured depending on task-specific characteristics. When including the break time, the noise levels increased by approximately 1 dBA during the break, combining 0.8 dBA in the lunch hours and 0.2 dBA for the preparation of the sampling instrument. When excluding the break time, the levels of noise exposure collected using a Korean Occupational Safety and Health Administration (KOSHA) guide tended to be underestimated compared to those using the U.S. OSHA method. When including the break times, the proportion of noise exposure levels exceeding the compliance exposure limit declined from 37.9% to 34.5%, indicating that the break times might affect the decrease in the noise exposure levels. Taken together, shipbuilding workers could possibly be exposed to much greater amounts of noise exposure during break times in the shipbuilding processes, and the noise exposure levels in the department of painting were high. Therefore, it is recommended that industrial hygienists collect exposure monitoring data of occupational noise one hour after their job tasks begin and then consecutively monitor the noise exposure levels for at least 6 h including the break periods for each day.
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Bruit au travail , Exposition professionnelle , Humains , Industrie , Bruit au travail/effets indésirables , Exposition professionnelle/analyse , République de Corée , États-Unis , Occupational Safety and Health Administration (USA)RÉSUMÉ
A novel harvesting interface for multiple piezoelectric transducers (PZTs) is proposed for high-voltage energy harvesting. Pre-biasing a PZT prior to its mechanical deformation increases its damping force, resulting in higher energy extraction. Unlike the conventional harvesters where a PZT-generated output is assumed to be continuous sinusoidal and output polarity is assumed to be alternating every cycle, PZT-generated output from human motion is expected to be random. Therefore, in the proposed approach, energy is invested to the PZT only when PZT deformation is detected. Upon the motion detection, energy stored at a storage capacitor (CSTOR) from earlier energy harvesting cycle is invested to pre-bias PZT, enhancing energy extraction. The harvested energy is transferred to back CSTOR for energy investment on the next cycle and then excess energy is transferred to the battery. In addition, partial electric charge extraction (PECE) is adapted to extract a partial amount of charges from the PZT every time its voltage approaches the process limit of 40 V. Simulations with 0.35 µm BCD process show 7.61× (with PECE only) and 8.38× (with PECE and energy investment) improvement compared to the conventional rectifier-based harvesting scheme Proposed harvesting interface successfully harvests energy from excitations with open-circuit voltages up to 100 V.
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Among many biomaterials, gelatin methacrylate (GelMA), a photocurable protein, has been widely used in 3D bioprinting process owing to its excellent cellular responses, biocompatibility and biodegradability. However, GelMA still shows a low processability due to the severe temperature dependence of viscosity. To overcome this obstacle, we propose a two-stage temperature control system to effectively control the viscosity of GelMA. To optimize the process conditions, we evaluated the temperature of the cooling system (jacket and stage). Using the established system, three GelMA scaffolds were fabricated in which different concentrations (0, 3 and 10 wt%) of silanated silica particles were embedded. To evaluate the performances of the prepared scaffolds suitable for hard tissue regeneration, we analyzed the physical (viscoelasticity, surface roughness, compressive modulus and wettability) and biological (human mesenchymal stem cells growth, western blotting and osteogenic differentiation) properties. Consequently, the composite scaffold with greater silica contents (10 wt%) showed enhanced physical and biological performances including mechanical strength, cell initial attachment, cell proliferation and osteogenic differentiation compared with those of the controls. Our results indicate that the GelMA/silanated silica composite scaffold can be potentially used for hard tissue regeneration.
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This study aims to evaluate occupational exposure models by comparing model estimations of Stoffenmanager, version 8.2, and exposure scores calculated using a new exposure model with personal exposure measurements for styrene used in the fiberglass-reinforced plastic (FRP) lamination processes in Korea. Using the collected exposure measurements (n = 160) with detailed contextual information about the type of process, working conditions, local exhaust ventilation, respiratory protections, and task descriptions, we developed a new model algorithm to estimate the score for occupational exposures on situation level. We assumed that the source of exposure originates from the near field only (within the breathing zone of workers). The new model is designed as a simple formula of multiplying scores for job classification, exposure potential, engineering controls, chemical hazard, and exposure probability and then dividing the score for workplace size. The final score is log-transformed, ranging from 1 to 14, and the exposure category is divided into four ratings: no exposure (1), low (2), medium (3), and high (4) exposures. Using the contextual information, all the parameters and modifying factors are similarly entered into the two models through direct translation and coding processes with expert judgement, and the exposure estimations and scores using the two models are calculated for each situation. Overall bias and precision for Stoffenmanager are -1.00 ± 2.07 (50th) and -0.32 ± 2.32 (90th) for all situations (n = 36), indicating that Stoffenmanager slightly underestimated styrene exposures. Pearson's correlation coefficients are significantly high for Stoffenmanager (r = 0.87) and the new model (r = 0.88), and the correlation between the two models is significantly high (r = 0.93) (p < 0.01). Therefore, the model estimations using Stoffenmanager and the new model are significantly correlated with the styrene exposures in the FRP lamination process. Further studies are needed to validate and calibrate the models using a larger number of exposure measurements for various substances in the future.
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Polluants atmosphériques d'origine professionnelle , Verre , Exposition professionnelle , Matières plastiques , Styrène , Polluants atmosphériques d'origine professionnelle/analyse , Polluants atmosphériques d'origine professionnelle/toxicité , Surveillance de l'environnement , Verre/analyse , Humains , Modèles théoriques , Matières plastiques/analyse , Matières plastiques/toxicité , République de Corée , Appréciation des risques , Styrène/analyse , Styrène/toxicitéRÉSUMÉ
Chinese hamster ovary (CHO) cells are used for industrial production of protein-based therapeutics (i.e., "biologics"). Here we describe a method for combining systems-level kinetic models with a synthetic biology platform for multigene overexpression to rationally perturb N-linked glycosylation. Specifically, we sought to increase galactose incorporation on a secreted Immunoglobulin G (IgG) protein. We rationally design, build, and test a total of 23 transgenic cell pools that express single or three-gene glycoengineering cassettes comprising a total of 100 kilobases of engineered DNA sequence. Through iterative engineering and model refinement, we rationally increase the fraction of bigalactosylated glycans five-fold from 11.9% to 61.9% and simultaneously decrease the glycan heterogeneity on the secreted IgG. Our approach allows for rapid hypothesis testing and identification of synergistic behavior from genetic perturbations by bridging systems and synthetic biology.
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Produits biologiques/synthèse chimique , Immunoglobuline G/métabolisme , Génie métabolique/méthodes , Maturation post-traductionnelle des protéines , Animaux , Séquence nucléotidique , Cellules CHO , Cricetinae , Cricetulus , Galactose/métabolisme , Galactosyltransferases/génétique , Galactosyltransferases/métabolisme , Glycosylation , Humains , Polyosides/métabolisme , Protéines recombinantes/génétique , Protéines recombinantes/métabolisme , Biologie synthétique/méthodes , TransgènesRÉSUMÉ
An energy-harvesting interface for kinetic energy harvesting from high-voltage piezoelectric and triboelectric generators is proposed in this paper. Unlike the conventional kinetic energy-harvesting interfaces optimized for continuous sinusoidal input, the proposed harvesting interface can efficiently handle irregular and random high voltage energy inputs. An N-type mosfet (NMOS)-only power stage design is introduced to simplify power switch drivers and minimize conduction loss. Controller active mode power is also reduced by introducing a new voltage peak detector. For efficient operation with potentially long intervals between random kinetic energy inputs, standby power consumption is minimized by monitoring the input with a 43 pW wake-up controller and power-gating all other circuits during the standby intervals. The proposed harvesting interface can harvest energy from a wide range of energy inputs, 10 s of nJ to 10 s of µJ energy/pulse, with an input voltage range of 5-200 V and an output range of 2.4-4 V under discontinuous as well as continuous excitation. The proposed interface is examined in two scenarios, with integrated power stage devices (maximum input 45 V) and with discrete power stage devices (maximum input 200 V), and the harvesting efficiency is improved by up to 600% and 1350%, respectively, compared to the case when harvesting is performed with a full bridge rectifier.