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The Road to My Car: The Development and Limitation of Koreans Desire for Car Ownership
No full text화석에너지를 토대로 만들어진 현대문명은 기후위기와 생태계 파괴 등으로 파생되는 각종 문제가 일어나고 지구 생태계와 인류 사회가 위협받게 되면서 그 존립 기반이 흔들리고 있다. 자동차는 화석에너지 체제와 대량생산‧대량소비 사회의 상징으로서, 현대문명의 위기 문제를 성찰하는 데 적절한 대상이 된다. 이러한 문제의식에서 한국에서의 자동차 소유 욕망을 비판적으로 살펴보았다.
먼저 한국에서 다수가 자가용을 갖게 되는 마이카 시대의 기점을 살펴보았다. 자동차 등록 대수와 마이카 담론 추이를 볼 때, 3저 호황과 더불어 1인당 GDP가 급상승하고 자동차의 대량생산체제가 확립되는 1980년대 후반에 비로소 마이카 시대에 접어들었다. 1970년대 이후 한국 사회에서의 자동차 소유 욕구가 시간이 갈수록 더욱 확산했고, 1980년대 들어서면 자동차에 대한 경쟁적이고 과시적인 소비 현상이 나타났다. 다음으로 자동차 소유 욕망이 함께한 자동차 보급은 사회 전반의 이동성(mobility)을 증대시키며 자동차 여행의 확장, 외식과 쇼핑문화의 확대로 이어졌고, 자동차 연관 산업의 발달을 촉진했다. 이러한 사회문화적, 산업적 변화는 자동차 중심 교통체계의 형성과 함께했다. 한국의 교통예산은 자동차 운행을 위한 도로 중심으로 편성되었다. 육교와 지하도 등 교통시설은 자동차 운행을 이동의 중심에 놓고 교통약자의 보행권을 배제한 것이었다. 한편, 자동차 소유 욕망의 실현과 자동차 중심 교통체계는 사회생태적 비용을 증가시켰다. 교통 정체와 교통사고 등 외부비용의 증가와 생태계 파괴, 대기오염 및 온실가스 배출은 현재까지 계속되고 있다. 끝으로 대량생산-유통-소비-폐기의 물질대사에 따른 인간의 다른 인간과 자연에 대한 착취와 기후위기를 일으키는 자동차 사회로부터 벗어나기 위한 로드맵을 제시하고자 하였다.
Modern civilization, which was built on fossil energy, is shaken by various problems such as climate crisis and ecological destruction. As a symbol of the fossil energy system, mass production and mass consumption society, the automobile is an appropriate object to reflect on the crisis of modern civilization. With this in mind, I critically examined the desire for car ownership in Korea.
First, I considered the beginning of the My Car Era, when the majority of Korea began to have their cars. Based on the number of car registrations and the trend of my car discourse, the my car era was finally entered in the late 1980s, when GDP per capita rose rapidly along with the three-low boom and the mass production system of cars was established. Since the 1970s, Korean societys desire for car ownership has become more widespread over time, and the competitive and ostentatious consumption of automobiles became prominent in the 1980s. Next, the proliferation of automobiles, coupled with the desire for car ownership, increased mobility across society, leading to the expansion of automobile travel, the expansion of dining and shopping culture, and the development of automobile-related industries. These socio-cultural and industrial changes have been accompanied by the formation of an automobile-centered transportation system. South Korea's transportation budget was organized around roads for automobile transportation. Transportation facilities such as overpasses and underpasses put automobiles at the center of movement and excluded the right to walk for the transportation disadvantaged. Meanwhile, the realization of the desire to own a car and the car-centred transportation system increased the socio-ecological costs. The increase in transportation external costs such as traffic congestion and traffic accidents, ecosystem destruction, air pollution, and greenhouse gas emissions continue to this day. Finally, this paper attempted to present a roadmap to escape from the car society that causes climate crisis and human exploitation of humans and nature through the material metabolism of mass production, distribution, consumption, and disposal.N
Attention Failures Cause Workplace Accidents: Why Workers Ignore Hazards and What To Do About It
No full textAccidents readily occur when workers are not attentive to the hazards of their work. For some professionals, such as workers in the construction and mining industry, exposure to workplace hazards occurs on a daily basis. Such repetitive exposure to workplace hazards poses unique challenges for the attention of workers. This review explores how, in the absence of negative consequences, repetitive exposure to hazards decreases attention to them. Recommendations, informed by the science of attention, suggest how to combat the tendency to ignore frequently-exposed hazards and restore worker vigilance, thereby reducing the frequency of workplace accidents. Experiential training incorporating virtual reality holds some promise.N
Genetic Characterization and Phylogeographic Analysis of the First H13N6 Avian Influenza Virus Isolated from Vega Gull in South Korea
No full textAvian influenza virus (AIV) is a pathogen with zoonotic and pandemic potential. Migratory birds are natural reservoirs of all known subtypes of AIVs, except for H17N10 and H18N11, and they have been implicated in previous highly pathogenic avian influenza outbreaks worldwide. This study identified and characterized the first isolate of the H13N6 subtype from a Vega gull (Larus vegae mongolicus) in South Korea. The amino acid sequence of hemagglutinin gene showed a low pathogenic AIV subtype and various amino acid substitutions were found in the sequence compared to the reference sequence and known H13 isolates. High sequence homology with other H13N6 isolates was found in HA, NA, PB1, and PA genes, but not for PB2, NP, M, and NS genes. Interestingly, various point amino acid mutations were found on all gene segments, and some are linked to an increased binding to human-type receptors, resistance to antivirals, and virulence. Evolutionary and phylogenetic analyses showed that all gene segments are gull-adapted, with a phylogeographic origin of mostly Eurasian, except for PB2, PA, and M. Findings from this study support the evidence that reassortment of AIVs continuously occurs in nature, and migratory birds are vital in the intercontinental spread of avian influenza viruses.Y
Effectiveness of a collagen matrix seal and xenograft in alveolar ridge preservation: an experimental study in dogs
No full textMajority of previous studies on alveolar ridge preservation (ARP) used collagen membranes as barrier membranes, and further evidence for ARP in dehiscent extraction sockets with a deproteinized bovine bone mineral (DBBM) and matrix is needed. The aim of this study is to assess the impact of non-cross linked collagen membranes (membrane) and crosslinked collagen matrices (matrix) on ARP using DBBM in extraction sockets with buccal dehiscence. In six mongrel dogs, the mesial roots of three mandibular premolars (P2, P3, and P4) were extracted 1month after dehiscence defect induction. Two experimental groups were randomly assigned: (1) DBBM with a membrane (DBBM/membrane group) and (2) DBBM with a matrix (DBBM/matrix group). Three-dimensional (3D) volumetric, microcomputed tomography (μCT), and histologic analyses were performed to assess the ridge preservation. Both groups were effective to maintain the ridge width (p > 0.05), and the DBBM/matrix group showed more favorable soft tissue regeneration and bone quality in the histological analysis (p = 0.05). Based on these results, DBBM/matrix could be better choice for ARP in cases of buccal dehiscence defects. © 2024, The Author(s).Y
Phase Engineering of Two-Dimensional Transition Metal Dichalcogenides
No full textSince the successful isolation of single-layer graphene with an atomic thickness, various van der Waals (vdW) materials have been intensively studied owing to their unique properties. Among the families of vdW materials, transition metal dichalcogenides (TMDs) have served as representatives because of their diverse band structures and intriguing quantum states, unlike those observed in their bulk counterparts. Particularly, unconventional polymorphic phases of TMDs increase the degrees of freedom in device fabrication and property modulation. As variations in structural phases significantly change the electrical, physical, and chemical properties of materials, phase engineering is essential for the new paradigm of TMD-based devices. In this review, diverse strategies that can induce and control structural phases in TMDs are explored. After introducing the polymorphic phase changes and the resulting electronic band structures, the various empirical approaches used for manipulating phases in vdW materials, including phase-selective synthesis and post-synthesis treatments, are summarized. The group-VI TMDs are considered as reference, and the analysis is extended to other TMDs across various groups in the periodic table. In addition to providing a comprehensive survey of the recent progress in TMD applications, the challenges for TMD applications and potential opportunities in emerging fields are discussed. This review critically explores strategies for inducing and controlling structural phases in vdW transition metal dichalcogenides (TMDs). It covers empirical methods like phase-selective synthesis and postsynthesis treatments, focusing on group-VI TMDs as a primary reference and extending the analysis to other TMDs. The review also addresses potential challenges and opportunities concerning TMD applications in emerging fields.image (c) 2023 WILEY-VCH GmbHY
High Thermoelectric Performance in Solution-Processed Semicrystalline PEDOT:PSS Films by Strong Acid-Base Treatment: Limitations and Potential
No full textThermoelectric (TE) generation with solution-processable conducting polymers offers substantial potential in low-temperature energy harvesting based on high tunability in materials, processes, and form-factors. However, manipulating the TE and charge transport properties accompanies structural and energetic disorders, restricting the enhancement of thermoelectric power factor (PF). Here, solution-based strong acid-base treatment techniques are introduced to modulate the doping level of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) thin films with preserving its molecular orientation, enabling to achieve a remarkably high PF of 534.5 mu W m(-1) K-2. Interestingly, theoretical modeling suggested that further de-doping can increase the PF beyond the experimental value. However, it is impossible to reach this value experimentally, even without any degradation of PEDOT crystallinity. Uncovering the underlying reason for the limitation, an analysis of the relationship among the microstructure-thermoelectric performance-charge transport property revealed that inter-domain connectivity via tie-chains and the resultant percolation for transport are crucial factors in achieving high TE performance, as in charge transport. It is believed that the methods and fundamental understandings in this work would contribute to the exploitation of conducting polymer-based low-temperature energy harvesting.Y
Fast and accurate protein structure search with Foldseek
No full textAs structure prediction methods are generating millions of publicly available protein structures, searching these databases is becoming a bottleneck. Foldseek aligns the structure of a query protein against a database by describing tertiary amino acid interactions within proteins as sequences over a structural alphabet. Foldseek decreases computation times by four to five orders of magnitude with 86%, 88% and 133% of the sensitivities of Dali, TM-align and CE, respectively. Foldseek speeds up protein structural search by four to five orders of magnitude.Y
Bridging the Gap Between Self-Report and Behavioral Laboratory Measures: A Real-Time Driving Task With Inverse Reinforcement Learning
No full textA major challenge in assessing psychological constructs such as impulsivity is the weak correlation between self-report and behavioral task measures that are supposed to assess the same construct. To address this issue, we developed a real-time driving task called the "highway task," in which participants often exhibit impulsive behaviors mirroring real-life impulsive traits captured by self-report questionnaires. Here, we show that a self-report measure of impulsivity is highly correlated with performance in the highway task but not with traditional behavioral task measures of impulsivity (47 adults aged 18-33 years). By integrating deep neural networks with an inverse reinforcement learning (IRL) algorithm, we inferred dynamic changes of subjective rewards during the highway task. The results indicated that impulsive participants attribute high subjective rewards to irrational or risky situations. Overall, our results suggest that using real-time tasks combined with IRL can help reconcile the discrepancy between self-report and behavioral task measures of psychological constructs.Y
Neural correlates of model-based behavior in internet gaming disorder and alcohol use disorder
No full textBackground: An imbalance between model-based and model-free decision-making systems is a common feature in addictive disorders. However, little is known about whether similar decision-making deficits appear in internet gaming disorder (IGD). This study compared neurocognitive features associated with model-based and model-free systems in IGD and alcohol use disorder (AUD). Method: Participants diagnosed with IGD (n = 22) and AUD (n = 22), and healthy controls (n = 30) performed the two-stage task inside the functional magnetic resonance imaging (fMRI) scanner. We used computational modeling and hierarchical Bayesian analysis to provide a mechanistic account of their choice behavior. Then, we performed a model-based fMRI analysis and functional connectivity analysis to identify neural correlates of the decision-making processes in each group. Results: The computational modeling results showed similar levels of model-based behavior in the IGD and AUD groups. However, we observed distinct neural correlates of the model-based reward prediction error (RPE) between the two groups. The IGD group exhibited insula-specific activation associated with model-based RPE, while the AUD group showed prefrontal activation, particularly in the orbitofrontal cortex and superior frontal gyrus. Furthermore, individuals with IGD demonstrated hyper-connectivity between the insula and brain regions in the salience network in the context of model-based RPE. Discussion and Conclusions: The findings suggest potential differences in the neurobiological mechanisms underlying model-based behavior in IGD and AUD, albeit shared cognitive features observed in computational modeling analysis. As the first neuroimaging study to compare IGD and AUD in terms of the model-based system, this study provides novel insights into distinct decision-making processes in IGD.Y
Gingivo-Periosteal Expansion of Edentulous Jaw Crest with An Osmotic Self-Inflatable Expander: A Preclinical in Vivo Study
No full textThis study examined the biocompatibility and expansion volume of tissue expanders utilizing rabbits and beagles as experimental models. The self-inflatable expander was provided using a Tissue balloon® (Neobiotech Co., Seoul, Korea). In 9 adult rabbits, a Tissue balloon® was placed under the lateral mandibular periosteum via an extraoral approach. After 2, 3, and 4 weeks (n=3), the expanders were removed, and soft tissue and bone samples were collected for analysis. Histomorphometric analysis and measurements of expander characteristics were performed. In 5 Beagles, all premolars were extracted. Three months after extraction, tissue expanders were placed in the maxilla and mandible, adjacent to dental extraction sites, and removed after 3 weeks. Gingival parameters were measured before and after expansion. Blood perfusion in the oral mucosa was assessed using a laser Doppler flowmeter at different time points. After three weeks, dogs were euthanized, and tissue samples were collected for histologic analysis, focusing on inflammatory response, bone formation, and gingival thickness changes. In the rabbit study, measurements of size, weight, and volume showed significant increases over 4 weeks. Swelling peaked at 2 weeks postimplantation and then gradually stabilized. Histologic examination revealed no signs of inflammation, and expanders were covered by collagen-rich capsules. Some bone resorption was noted due to pressure from the expanders, but the resorption was not significant. In the beagle study, twenty tissue expanders were implanted; 1 expander was lost, and 9 wounds dehisced during soft tissue healing. However, no signs of infection were noted. Histologic evaluation showed bone atrophy, attributed to swelling pressure, at the recipient site. Gingival thickness was not decreased. Perfusion measurements indicated that expansion did not affect microvascular circulation adversely. Overall, both studies suggest that tissue expanders demonstrate biocompatibility and successful expansion volume in vivo, with minimal adverse effects on surrounding tissues and microvascular circulation.N