Publications by authors named "Jun Koo"

Article Synopsis
  • The study investigates the use of Precautionary Allergen Labeling (PAL) in baby food products in Korea, finding that it is present in 91.8% of items but only validated in 16.7% of cases.
  • ELISA tests revealed minimal contamination from cow’s milk, while no hen's egg white was detected, indicating possible gaps in safety.
  • Surveys showed that guardians, especially those with children having food allergies, are dissatisfied with current PAL practices and prefer clearer, more informative labeling, suggesting a need for a comprehensive revision to improve safety.
View Article and Find Full Text PDF

Most triblock copolymer-based physical hydrogels form three-dimensional networks through micellar packing, and formation of polymer loops represents a topological defect that diminishes hydrogel elasticity. This effect can be mitigated by maximizing the fraction of elastically effective bridges in the hydrogel network. Herein, we report hydrogels constructed by complexing oppositely charged multiblock copolymers designed with a sequence pattern that maximizes the entropic and enthalpic penalty of micellization.

View Article and Find Full Text PDF

This Review presents an overview of all-organic nanocomposites, a sustainable alternative to organic-inorganic hybrids. All-organic nanocomposites contain nanocellulose, nanochitin, and aramid nanofibers as highly rigid reinforcing fillers. They offer superior mechanical properties and lightweight characteristics suitable for diverse applications.

View Article and Find Full Text PDF

The accumulation of petroleum-based plastics on our planet is causing serious environmental pollution. Biodegradable plastics, promoted as eco-friendly solutions, hold the potential to address this issue. However, their impact on the environment and the mechanisms of their natural degradation remain inadequately understood.

View Article and Find Full Text PDF

Self-healing polymeric materials, which can repair physical damage, offer promising prospects for protective applications across various industries. Although prolonged durability and resource conservation are key advantages, focusing solely on mechanical recovery may limit the market potential of these materials. The unique physical properties of self-healing polymers, such as interfacial reduction, seamless connection lines, temperature/pressure responses, and phase transitions, enable a multitude of innovative applications.

View Article and Find Full Text PDF

The structure-property paradox of biological tissues, in which water-rich porous structures efficiently transfer mass while remaining highly mechanically stiff, remains unsolved. Although hydrogel/sponge hybridization is the key to understanding this phenomenon, material incompatibility makes this a challenging task. Here we describe hydrogel/sponge hybrids (hydrospongels) that behave as both ultrastiff water-rich gels and reversibly squeezable sponges.

View Article and Find Full Text PDF
Article Synopsis
  • Growing concerns over plastic waste have led to the search for biodegradable alternatives like poly(lactic acid) (PLA), but issues like low hydrolysis resistance limit their durability.
  • This study explores a layer-by-layer (LBL) assembly approach to coat PLA with biodegradable nanocellulose/nanochitin, enhancing its resistance to hydrolysis through microwave irradiation and crosslinking.
  • Results showed that this coating improved PLA's durability, maintaining its mechanical properties and offering potential for sustainable packaging solutions with a longer shelf life.
View Article and Find Full Text PDF

Background: Mobile health (mHealth) services enable real-time measurement of information on individuals' biosignals and environmental risk factors; accordingly, research on health management using mHealth is being actively conducted.

Objective: The study aims to identify the predictors of older people's intention to use mHealth in South Korea and verify whether chronic disease moderates the effect of the identified predictors on behavioral intentions.

Methods: A cross-sectional questionnaire study was conducted among 500 participants aged 60 to 75 years.

View Article and Find Full Text PDF
Article Synopsis
  • The study highlights the importance of low-density lipoprotein (LDL) cholesterol as a key marker for cardiovascular disease and critiques the Friedewald equation for estimating LDL, especially for South Korean populations.
  • Utilizing data from the Korean National Health and Nutrition Examination Survey (2009-2019), researchers developed a new equation tailored to estimate LDL cholesterol specifically for South Koreans.
  • Results showed that the new estimation model outperformed existing equations, with lower misclassification rates and better accuracy, particularly when triglyceride levels were below 400 mg/dL.
View Article and Find Full Text PDF

Objectives: This study was conducted to elucidate the effects of an air quality warning system (AQWS) implemented in January 2015 in Korea by analyzing changes in the incidence and exacerbation rates of environmental diseases.

Methods: Data from patients with environmental diseases were extracted from the National Health Insurance Service-National Sample Cohort database from 2010 to 2019, and data on environmental risk factors were acquired from the AirKorea database. Patient and meteorological data were linked based on residential area.

View Article and Find Full Text PDF

This study aims to explore regional health disparities in hypertension-related hospitalizations and confirm this difference according to the states of continuity of care (COC). We used the National Health Insurance Service National Sample Cohort data from 2002 to 2019. The dependent variable, hypertension-related hospitalization, included hospitalization for hypertensive diseases (I10-I13, I15), ischemic heart disease (I20-I25), and cerebrovascular disease (I60-I69).

View Article and Find Full Text PDF

Composite materials have been extensively studied to optimize properties such as lightness and strength, which are the advantages of plastics. We prepared a highly concentrated (30 wt %) nylon/chitosan nanowhisker (CSW) masterbatch by blending nylon 6,10 and CSW by solvent casting to achieve high dispersion efficiency while considering an industrial setting. Subsequently, 0.

View Article and Find Full Text PDF

Among plastic items, single-use straws are particularly detrimental to marine ecosystems because such straws, including those made of poly(lactic acid) (PLA), are sharp and extremely slowly degradable in the ocean. While paper straws are promising alternatives, they exhibit hydration-induced swelling even when coated with a non-degradable plastic coating and promote effervescence (fizzing) in soft drinks owing to their surface heterogeneities. In this study, upgraded paper straw is coated with poly(butylene succinate) cellulose nanocrystal (PBS/CNC) composites.

View Article and Find Full Text PDF

Background: Catastrophic health expenditure (CHE) represents out-of-pocket payment as a share of household income. Most previous studies have focused on incidence aspects when assessing health policy effects. However, because CHE incidence is a binary variable, the effect of the health policy could not accurately be evaluated.

View Article and Find Full Text PDF

This study aimed to determine the effect of the presence or absence of avoidable hospitalization before acquiring coronavirus disease (COVID-19) on COVID-19-related deaths. This study used the total NHIS-COVID-19 dataset comprising domestic COVID-19 patients, provided by the National Health Insurance Service (NHIS) in South Korea. We conducted logistic regression and double robust estimation (DRE) to confirm the effect of avoidable hospitalization on COVID-19-related deaths.

View Article and Find Full Text PDF

To assess the effectiveness of continuity of care policies by identifying the impact of a chronic disease management program on the continuity of care in patients with hypertension in South Korea. The propensity score matching method was used to control selection bias, and the difference-in-differences method was used to compare the impact on the treatment and control groups according to the policy intervention. The continuity of care index of hypertensive patients using the difference-in-differences analysis outcome of the chronic disease management program was higher than that of the non-participating hypertensive patients.

View Article and Find Full Text PDF

As plastic consumption has increased, environmental problems associated with the accumulation of plastic wastes have started to emerge. These include the non-degradability of plastic and its disintegration into sub-micron particles. Although some biodegradable plastic products have been developed to relieve the landfill and leakage burden, a significant portion of discarded plastics are inevitably still incinerated.

View Article and Find Full Text PDF

Although biodegradable plastics are gradually emerging as an effective solution to alleviate the burgeoning plastic pollution, their performance is currently trivial for commercialization. A proposed two-pronged strategy to overcome this limitation includes (1) preparation of the nanocomposites from biorenewable nano-fillers to preserve their biodegradability and (2) tailoring their properties to meet the diverse demands in various applications. Herein, we report the preparation of biodegradable nanocomposites composed of poly(butylene succinate) (PBS) and cellulose nanocrystals (CNCs) (loading of 0.

View Article and Find Full Text PDF

Gluing dynamic, wet biological tissue is important in injury treatment yet difficult to achieve. Polymeric adhesives are inconvenient to handle due to rapid cross-linking and can raise biocompatibility concerns. Inorganic nanoparticles adhere weakly to wet surfaces.

View Article and Find Full Text PDF

Aluminum-coated polypropylene films are commonly used in food packaging because aluminum is a great gas barrier. However, recycling these films is not economically feasible. In addition, their end-of-life incineration generates harmful alumina-based particulate matter.

View Article and Find Full Text PDF

Background: Bone tumors can cause severe pain and poor quality of life due to recurrence and non-achievement of complete remission after surgery, chemotherapy, or radiotherapy. Radiofrequency ablation (RFA) can be considered for minimally invasive treatment of bone tumors that are difficult to radically excise. In this study, RFA was performed for bone tumors that were difficult to radically excise and did not respond to surgery, chemotherapy, or radiotherapy due to their large sizes and/or locations.

View Article and Find Full Text PDF

In the precarious situation caused by the COVID-19 pandemic, the use of messenger ribonucleic acid (mRNA) vaccines is promising for prevention against the infection. However, this type of vaccine has not been effectively commercialized because it needs to be stored and transported at ultracold conditions. mRNA vaccines exposed to undesired temperatures may not show any visible changes but can deteriorate and cause negative effects.

View Article and Find Full Text PDF

The demand for face masks is increasing exponentially due to the coronavirus pandemic and issues associated with airborne particulate matter (PM). However, both conventional electrostatic- and nanosieve-based mask filters are single-use and are not degradable or recyclable, which creates serious waste problems. In addition, the former loses function under humid conditions, while the latter operates with a significant air-pressure drop and suffers from relatively fast pore blockage.

View Article and Find Full Text PDF

Objective: The study aims to understand the relationship between the living-alone period and depressive symptoms among the elderly in South Korea.

Methods: The study obtained data on the elderly over 65 years old from the 2006 to 2019 Korea Welfare Panel Study. Generalized estimating equation (GEE) analysis was performed to understand changes in depressive symptoms over periods of living alone.

View Article and Find Full Text PDF

Biodegradable aliphatic polyesters need to be tough for commodity-plastic applications, such as disposable bags. Herein, we show that chitosan nanowhiskers (CsWs) prepared from naturally abundant chitin is an effective nanofiller that reinforces the strength and toughness of poly(butylene succinate) (PBS). In-situ polycondensation of an aqueous solution of processed CsWs led to a PBS nanocomposite with the highest tensile strength (77 MPa) and elongation at break (530%) reported to date for all PBS types at a minimal nanofiller content of 0.

View Article and Find Full Text PDF