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Life history theory suggests that in harsh, unpredictable environments, individuals may benefit from adopting a fast life history strategy. This may involve experiencing boredom more frequently and intensely as an adaptive mechanism to seek novel stimuli, potentially increasing the number of sexual partners and offspring. This study explored the relationship between trait boredom—a chronic characteristic of feeling bored—and fast life history strategies. Our findings confirmed a positive association between boredom proneness and fast life history strategies at both individual and country levels. In Study 1, fast life history strategy was positively correlated with boredom proneness and mediated the relationship between perceived childhood support/resources and boredom proneness. In Study 2, we conducted a multi-level analysis using secondary data from 15 countries. The results showed that countries with higher boredom proneness scores showed more indicators of faster life history strategies. These results suggest that trait boredom may be a functional characteristic of fast life history strategists. This study is the first empirical investigation of trait boredom within a life history framework, highlighting trait boredom's functional role from evolutionary and ecological perspectives.

Sarcoptic mange, caused by Sarcoptes scabiei, has been reported in various wildlife species, with the potential to impact populations. While it has been documented in some wildlife species and domestic animals, it has not been previously reported in wild boars in South Korea. In March and April 2022, skin samples from nine wild boars and one raccoon dog with suspected sarcoptic mange were submitted to the NIWDC. These samples were tested and confirmed the presence of S. scabiei in six wild boars and one raccoon dog. Genetic analysis of the cox-1 gene from mites indicated that the gene was identical and belonged to the same haplotype in both host species. Serological survey of 658 wild boars, collected from March 2022 to February 2023, revealed a nationwide seroprevalence of 5.47%. The highest seroprevalence was in Gyeongsangnam-do (9.82%); however, regional differences in seroprevalence across the country were not statistically significant, suggesting the disease may be endemic across South Korea. Seroprevalence was highest in spring (16.84%), likely due to increased contact during winter. This study provides fundamental data on the genetic characteristics and distribution of S. scabiei mites in South Korean wild boars, emphasizing the need for continued surveillance to prevent further spread.

The reliability of inverse-mode silicon-germanium (SiGe) heterojunction bipolar transistors (HBTs) under dc stress and its potential impact on the performance of basic analog amplifiers are investigated. In order to properly reflect the stress effects in various circuit applications, the degradations under three different configurations (active bias, diode connection, and off state) were experimentally characterized with the stress voltages applied up to 3000 s for each case. Based on the changes in the Gummel response, the degradations in device parameters such as current gain (β), transconductance (gm), and base-to-emitter resistance (rπ) were extracted and compared with the forward-mode counterpart. In addition, with the use of a small-signal equivalent model of a SiGe HBT, simple single-stage analog amplifiers were simulated as representative examples and their circuit-level performance metrics including gain and bandwidth were studied to estimate degradation characteristics with accumulated stress. It was found that transimpedance gain decreases and operation bandwidth increases to different levels due to device degradation, whereas a voltage amplifier exhibited much less changes.

We investigated feeding by Calanus sinicus in the Yellow Sea over four seasons in 2019–2022 using the gut pigment method. Studying the feeding of copepods is important for understanding processes within food webs, but little is known about the feeding ecology of C. sinicus, a major consumer of primary production in the Yellow Sea. The seasonal mean ingestion rate of C. sinicus was 16.6–42.1 for copepodite stage I (CI), 24.1–41.8 for CII, and 32.7–58.5 ng chl ind.−1 d−1 for CIII, with different seasonal fluctuations in each stage. The seasonal mean ingestion rate was 45.8–114.4 for CIV, 50.2–189.3 for CV, 96.9–438.9 for females, and 69.8–132.3 ng chl ind.−1 d−1 for males, with higher values in spring and lower values in summer. The combined grazing impacts of C. sinicus from the CI to adult stages were 1.66%, 1.43%, 2.04%, and 0.65% in spring, summer, autumn, and winter, respectively. The ingestion rate of later developmental stages from CIV to adults was positively related to chlorophyll-a concentration rather than water temperature or salinity, according to a redundancy analysis. These results suggest that C. sinicus population in the Yellow Sea actively feeds on phytoplankton in spring and that most of the grazing impact is attributed to females.

This manuscript presents a comprehensive study on the assembly of microchips using fluidic self-assembly (FSA) technology, with a focus on optimizing the spacing between binding sites to improve yield and assembly. Through a series of experiments, we explored the assembly of microchips on substrates with varying binding site spacings, revealing the impact of spacing on the rate of undesired chip assembly across multiple sites. Our findings indicate a significant reduction in incorrect assembly rates as the spacing increases beyond a critical threshold of 140 μm. This study delves into the mechanics of chip alignment within the fluid medium, hypothesizing that the extent of the alloy’s grip on the chips at different spacings influences assembly outcomes. By analyzing cases of undesired assembly, we identified the relationship between binding site spacing and the area of chip contact, demonstrating a decrease in the combined left and right areas of chips as the spacing increases. The results highlight a critical spacing threshold, which, when optimized, could significantly enhance the efficiency and precision of microchip assembly processes using FSA technology. This research contributes to the field of microcomponent assembly, offering insights into achieving higher integration densities and precision in applications, such as microLED displays and augmented reality (AR) devices.

Reversible N6-adenosine methylation of mRNA, referred to as m6A modification, has emerged as an important regulator of post-transcriptional RNA processing. Numerous studies have highlighted its crucial role in the pathogenesis of diverse diseases, particularly cancer. Post-translational modifications of m6A-related proteins play a fundamental role in regulating the m6A methylome, thereby influencing the fate of m6A-methylated RNA. A comprehensive understanding of the mechanisms that regulate m6A-related proteins and the factors contributing to the specificity of m6A deposition has the potential to unveil novel therapeutic strategies for cancer treatment. This review provides an in-depth overview of our current knowledge of post-translational modifications of m6A-related proteins, associated signaling pathways, and the mechanisms that drive the specificity of m6A modifications. Additionally, we explored the role of m6A-dependent mechanisms in the progression of various human cancers. Together, this review summarizes the mechanisms underlying the regulation of the m6A methylome to provide insight into its potential as a novel therapeutic strategy for the treatment of cancer.

African swine fever (ASF), a highly contagious and severe hemorrhagic viral disease in swine, is emerging as a major threat not only in Korea but also worldwide. The first confirmed case of ASF in Korea was reported in 2019. Despite the occurrence of ASF in Korea, only a few studies have genetically characterized the causative ASF virus (ASFV). In this study, we aimed to genetically characterize the ASFV responsible for the 2019 outbreak in Korea. The genome of the ASFV isolated during the first outbreak in Korea was analyzed. The Korea/YC1/2019 strain has 188,950 base pairs, with a GC content of 38.4%. The complete genome sequence was compared with other ASFV genomes annotated in the NCBI database. The Korea/YC1/2019 strain shared the highest similarity with Georgia 2007, Belgium 2018/1, and ASFV-wbBS01 strains. This study expands our knowledge of the genetic diversity of ASFV, providing valuable information for epidemiology, diagnostics, therapies, and vaccine development.

Abstract This study aims to improve the efficiency of task switching in hospital laboratories. In a laboratory, several medical technicians perform multiple tasks. Technicians are not aware of the marginal amount of time it takes to switch between tasks, and this accumulation of lost minutes can cause the technician to worry more about the remaining working time than work quality. They rush through their remaining tasks, thereby rendering their work less efficient. For time optimization, we identified work changeover times to help maintain the work quality in the laboratory while reducing the number of task switching instances. We used the turnaround time (TAT) compliance rate of emergency room samples as an indicator to evaluate laboratory performance and the number of task switching instances as an index of the task performer perspective (TPP). We experimented with a monitoring system that populates the time for sample classification according to the optimal time for task switching. Through the proposed methodology, we successfully reduced not only the instances of task switching by 10% but also the TAT non-compliance rate from 4.97 to 2.66%. Consequently, the introduction of new methodology has greatly increased work efficiency.

African swine fever (ASF), a viral disease caused by the African swine fever virus (ASFV), is associated with high mortality rates in domestic pigs and wild boars. ASF has been spreading since its discovery in wild boars in Korea in October 2019. Genomic analyses have provided insights into the genetic diversity of the ASFV isolated from various regions, enabling a better understanding of the virus origin and transmission patterns. We conducted a genome analysis to evaluate the diversity and mutations of ASFV spreading among wild boars in Korea during 2019–2022. We compared the genomes of ASFV strains isolated from Korean wild boars and publicly available ASFV genomes. Genomic analysis revealed several single-nucleotide polymorphisms within multigene families (MGFs) 360-1La and 360-4L in Korean ASFV. MGF 360-1La and 360-4L variations were not observed in other ASFV strains, including those of genotype II. Finally, we partially analyzed MGFs 360-1La and 360-4L in ASFV-positive samples between 2019 and 2022, confirming the geographical distribution of the variants. Our findings can help identify new genetic markers for epidemiological ASFV analysis and provide essential information for effective disease management.

For improving self-heating effects (SHEs) in gate-all-around metal-oxide-semiconductor field-effect transistors (GAA MOSFETs), hetero-gate-dielectric (HGD) is utilized. The HGD consists of hafnium dioxide (HfO2) and silicon dioxide (SiO2), which has high thermal conductivity, hence SHEs are improved. In order to validate the HGD, technology computer-aided design (TCAD) simulation is performed through Synopsys Sentaurus three-dimensional (3D) tool. As a result, when the HGD is adopted in GAA MOSFETs, SHEs can be significantly improved from 498 K to 415 K. In addition, suppression of gate current, more than 2 orders, is also achieved because of bigger bandgap of SiO2 in HGD. Consequently, this structure takes advantage of higher thermal conductivity and bigger bandgap of SiO2, and higher permittivity of HfO2 for improving SHEs and gate leakage current.

Due to the prolonged COVID-19 pandemic, wearing masks has become essential for social interaction, disturbing emotion recognition in daily life. In the present study, a total of 39 Korean participants (female = 20, mean age = 24.2 years) inferred seven emotions (happiness, surprise, fear, sadness, disgust, anger, surprise, and neutral) from uncovered, mask-covered, sunglasses-covered faces. The recognition rates were the lowest under mask conditions, followed by the sunglasses and uncovered conditions. In identifying emotions, different emotion types were associated with different areas of the face. Specifically, the mouth was the most critical area for happiness, surprise, sadness, disgust, and anger recognition, but fear was most recognized from the eyes. By simultaneously comparing faces with different parts covered, we were able to more accurately examine the impact of different facial areas on emotion recognition. We discuss the potential cultural differences and the ways in which individuals can cope with communication in which facial expressions are paramount.

Spending money on one's self, whether to solve a problem, fulfill a need, or increase enjoyment, often heightens one's sense of happiness. It is therefore both surprising and important that people can be even happier after spending money on someone else. We conducted a close replication of a key experiment from Dunn, Aknin, and Norton (2008) to verify and expand upon their findings. Participants were given money and randomly assigned to either spend it on themselves or on someone else. Although the original study (N = 46) found that the latter group was happier, when we used the same analysis in our replication (N = 133), we did not observe a significant difference. However, we report an additional analysis, focused on a more direct measure of happiness, that does show a significant effect in the direction of the original. Follow-up analyses shed new insights into people's predictions about their own and others' happiness and their actual happiness when spending money for themselves or others.

In this article, an investigation has been performed to statistically analyze the entire subthreshold characteristics of tunnel field-effect transistor (TFET) depending on a gate work function variation (WFV). Firstly, the current variations are evaluated through turn-on voltage (VON) and threshold voltage (VT) with help of technology computer-aided design (TCAD) simulation. Secondly, the variation of VT and VON are quantitatively analyzed by coefficient of determination (R2) in the regression analysis. The R2 values are extracted according to the divided the gate prats. Finally, it is confirmed that the WFV of the gate parts causes the current variation in areas where tunneling is varied mainly according to the gate bias.

A feedback field-effect transistor (FBFET) is a novel device that uses a positive feedback mechanism. FBFET has a high on-/off ratio and is expected to realize ideal switching characteristics through steep changes from off-state to on-state. In this paper, we propose and optimize FBFET devices with asymmetric source/drain doping concentrations. Additionally, we discuss the changes in electrical characteristics across various channel length and channel thickness conditions and compare them with those of FBFET with a symmetric source/drain. This shows that FBFET with an asymmetric source/drain has a higher on-/off ratio than FBFET with a symmetric source/drain.

The Yellow Sea Bottom Cold Water (YSBCW) refers to seawater with a water temperature of 10 °C or less found at the bottom of the center of the Yellow Sea. The spatiotemporal variability of the YSBCW directly affects the distribution of organisms in the marine ecosystem. In this study, hydroacoustic and net surveys were conducted in April (spring) to understand the spatial distribution of the sound scattering layer (SSL) and estimate the density of Euphausia pacifica (E. pacifica) in the YSBCW. Despite the shallow water in the YSBCW region, E. pacifica formed an SSL, which was distributed near the bottom during the daytime; it showed a diel vertical migration (DVM) pattern of movement toward the surface during the nighttime. The mean upward and downward swimming speeds around sunset and sunrise were approximately 0.6 and 0.3–0.4 m/min, respectively. The E. pacifica density was estimated in the central, western, and eastern regions; the results were approximately 15.8, 1.3, and 10.3 g/m2, respectively, indicating significant differences according to region. The results revealed high-density distributions in the central and eastern regions related to the water temperature structure, which differs regionally in the YSBCW area. Additional studies are needed regarding the spatial distribution of E. pacifica in the YSBCW and its relationship with various ocean environmental parameters according to season. The results of this study contribute to a greater understanding of the structure of the marine ecosystem in the YSBCW.

Activation of microglia, the primary mediators of inflammation in the brain, is a major component of gliosis and neuronal loss in a number of age-related neurodegenerative disorders, such as Alzheimer’s disease (AD). The role of activated microglia in white matter, and its relationship with cognitive decline during aging are unknown. The current study evaluated microglia densities in the white matter of postmortem specimens from cognitively normal young adults, cognitively normal older adults, and cognitive “SuperAgers,” a unique group of individuals over age 80 whose memory test scores are at a level equal to or better than scores of 50-to-65-year-olds. Whole hemisphere sections from cognitively normal old, young, and “SuperAgers” were used to quantify densities of human leukocyte antigen-D related (HLA-DR)-positive activated microglia underlying five cortical regions. Statistical findings showed a significant main effect of group on differences in microglia density where cognitively normal old showed highest densities. No difference between SuperAgers and young specimens were detected. In two autopsied SuperAgers with MRI FLAIR scans available, prominent hyperintensities in periventricular regions were observed, and interestingly, examination of corresponding postmortem sections showed only sparse microglia densities. In conclusion, activated microglia appear to respond to age-related pathologic changes in cortical white matter, and this phenomenon is largely spared in SuperAgers. Findings offer insights into the relationship between white matter neuroinflammatory changes and cognitive integrity during aging.

Metal gate technology is one of the most important methods used to increase the low on-current of tunnel field-effect transistors (TFETs). However, metal gates have different work-functions for each grain during the deposition process, resulting in work-function variation (WFV) effects, which means that the electrical characteristics vary from device to device. The WFV of a planar TFET, double-gate (DG) TFET, and electron-hole bilayer TFET (EHBTFET) were examined by technology computer-aided design (TCAD) simulations to analyze the influences of device structure and to find strategies for suppressing the WFV effects in TFET. Comparing the WFV effects through the turn-on voltage (Vturn-on) distribution, the planar TFET showed the largest standard deviation (σVturn-on) of 20.1 mV, and it was reduced by −26.4% for the DG TFET and −80.1% for the EHBTFET. Based on the analyses regarding metal grain distribution and energy band diagrams, the WFV of TFETs was determined by the number of metal grains involved in the tunneling current. Therefore, the EHBTFET, which can determine the tunneling current by all of the metal grains where the main gate and the sub gate overlap, is considered to be a promising structure that can reduce the WFV effect of TFETs.

In this paper, an investigation is performed to analyze the L-shaped tunnel field-effect transistor (TFET) depending on a gate work function variation (WFV) with help of technology computer-aided design (TCAD) simulation. Depending on the gate voltage, the three variations occur in transfer curves. The first one is the on-state current (ION) variation, the second one is the hump current (IHUMP) variation, and the last one is ambipolar current (IAMB) variation. According to the simulation results, the ION variation is sensitive depending on the size of the tunneling region and could be reduced by increasing the tunneling region. However, the IHUMP and IAMB variations are relatively irrelevant to the size of the tunneling region. In order to analyze the cause of this difference, we investigated the band-to-band tunneling (BTBT) rate according to WFV cases. The results show that when ION is formed in L-shaped TFET, the BTBT rate relies on the WFV in the whole region of the gate because the tunnel barrier is formed in the entire area where the source and the gate meet. On the other hand, when the IHUMP and IAMB are formed in L-shaped TFET, the BTBT rate relies on the WFV in the edge of the gate.

In this paper, analysis and optimization of surrounding channel nanowire (SCNW) tunnel field-effect transistor (TFET) has been discussed with the help of technology computer-aided design (TCAD) simulation. The SCNW TFET features an ultra-thin tunnel layer at source sidewall and shows a high on-current (ION). In spite of the high electrical performance, the SCNW TFET suffers from hump effect which deteriorates subthreshold swing (S). In order to solve the issue, an origin of hump effect is analyzed firstly. Based on the simulation, the transfer curve in SCNW TFET is decoupled into vertical- and lateral-BTBTs. In addition, the lateral-BTBT causes the hump effect due to low turn-on voltage (VON) and low ION. Therefore, the device design parameter is optimized to suppress the hump effect by adjusting thickness of the ultra-thin tunnel layer. Finally, we compared the electrical properties of the planar, nanowire and SCNW TFET. As a result, the optimized SCNW TFET shows better electrical performance compared with other TFETs.

In this report, a novel tunnel field-effect transistor (TFET) named ‘F-shaped TFET’ has been proposed and its electrical characteristics are analyzed and optimized by using a computer-aided design simulation. It features ultra-thin and a highly doped source surrounded by lightly doped regions. As a result, it is compared to an L-shaped TFET, which is a motivation of this work, the F-shaped TFET can lower turn-on voltage (VON) maintaining high on-state current (ION) and low subthreshold swing (SS) with the help of electric field crowding effects. The optimized F-shaped TFET shows 0.4 V lower VON than the L-shaped TFET with the same design parameter. In addition, it shows 4.8 times higher ION and 7 mV/dec smaller average SS with the same VON as that for L-shaped TFET.

The main challenge for tunnel field-effect transistors (TFETs) is achieving high on-current (Ion) and low subthreshold swing (SS) with reasonable ambipolar characteristics. In order to address these challenges, Ge-channel heterostructure TFET with Si source and drain region is proposed, and its electrical characteristics are compared to other TFET structures. From two-dimensional (2-D) device simulation results, it is confirmed that the Si/Ge heterostructure source junction improves Ion and SS characteristics by using the direct band-to-band tunneling current. Furthermore, the proposed structure shows suppressed ambipolar behavior since the Ge/Si heterostructure is used at the drain junction.

In this paper, a novel tunnel field-effect transistor (TFET) has been demonstrated. The proposed TFET features a SiGe channel, a fin structure and an elevated drain to improve its electrical performance. As a result, it shows high-level ON-state current (ION) and low-level OFF-state current (IOFF); ambipolar current (IAMB). In detail, its ION is enhanced by 24 times more than that of Si control group and by 6 times more than of SiGe control group. The IAMB can be reduced by up to 900 times compared with the SiGe control group. In addition, technology computer-aided design (TCAD) simulation is performed to optimize electrical performance. Then, the benchmarking of ON/OFF current is also discussed with other research group’s results.