Health concerns related to particulate matter (PM) pollution are on the rise globally. This study investigates the effects of the main components of PM on human airway epithelial cells (Calu-3), focusing on three distinct types: PM10-bound PAHs (including Benzo[a]anthracene and Benzo[b]fluoranthene), PM10-bound trace elements (containing arsenic and lead), and PM2.5-bound ions (comprising sodium and calcium). Calu-3 cells were exposed to these PM components at concentrations ranging from 2 to 100 μg/mL. Unexposed Calu-3 cells exhibited a 60% increase in metabolic activity after 12 hours. In contrast, exposure to PM components resulted in significant reductions in cell viability, with PM10-bound PAHs and PM10-bound trace elements causing decreases of 54% and 55% respectively, and PM2.5-bound ions leading to a 63% reduction at 100 μg/mL. Additionally, there was found to be a notable rise in the expression of proinflammatory cytokines IL-8 and TNF-α. Specifically, IL-8 levels increased by 456%, and TNF-α levels rose by 660% after 12 hours of exposure to PM2.5-bound ions. These findings indicate that the size and composition of fine dust particles play a critical role in their cytotoxic effects, contributing to increased cell death, membrane damage, and necrosis in airway epithelial cells.
India has been a member of the BRICS group since 2009. It has been a staunch advocate for the synergistic power. Their summits have focused on a wide range of topics, all of which share the common goal of reorganizing the global economic and political order. The BRICS nations have together accomplished several significant milestones which include the establishment of the New Development Bank, the BRICS Payment System, collaborative anti-terror programs, climate mitigation, green energy, and other such initiatives. South Africa played home to the 15th BRICS Summit, which took place in the August of 2023 and was centered around the theme of “BRICS and Africa: Partnership for Mutually Accelerated Growth, Sustainable Development, and Inclusive Multilateralism.” This essay considers issues from an Indian perspective that may pop up in the future BRICS summit.
Pararhabdepyris Gorbatovsky, 1995, is a small genus in Bethylidae (Hymenoptera, Chrysidoidea), currently comprising only six valid species worldwide. A new species is described and illustrated from South Korea. Pararhabdepyris sp. nov., which appears closely related to P. paradoxus, is characterized by the combination of the following characters: the basal two-thirds of the scape are dark castaneous, coxa and femora are dark castaneous, the median and submedian metapectal-propodeal disc is rugulose, and the transverse posterior carina is straight. Images of diagnostic characteristics and an updated key to the seven world species of the genus are presented.
An ameroid constrictor (AC) was placed to occlude the shunt vessel in a dog diagnosed with a single extrahepatic portocaval shunt, and the patient showed favorable outcomes post-surgery. However, the 1-year postoperative assessment revealed that the shunt vessel was completely occluded, but the AC had migrated into the abdominal cavity. The examination of the surgically removed migrated AC revealed an internal space filled with fibrous tissues with no swelling in the casein, and notably, the key remained securely in place. This is the first veterinary medicine case in which migration of the AC without dislodgement of ameroid key was identified.
전략문화란 한 국가의 전략공동체가 갖는 태도와 신념, 반복된 경험을 통해 습득되는 습관적인 행동 패턴의 총합이라 할 수 있다. 따라서 전략 문화의 관점에서 전쟁의 원인을 분석하는 것은 여타 전쟁의 원인을 분석 하는 데 있어 유용한 방법이 될 것이다. 본 연구에서는 러-우전쟁을 발 발한 러시아와 북한의 전략문화 형성요인을 물리적 요인, 정치·군사적 요 인, 사회·문화적 요인으로 분류하였다. 이어서 전략문화 형성의 핵심요인 을 중심으로 러시아의 방어적·공격적 전략문화의 변화와 특성을 이해하 고 한반도에서의 전쟁발발 가능성에 대한 검토와 대비의 필요성을 제기 하고자 하였다. 연구 결과 러시아는 자국의 방어를 위한 대외적인 팽창 정책, 방어와 공격의 이중성, 섬멸주의를 추구하는 전략문화를 견지하고 있음을 알 수 있었고, 북한은 생존과 이익을 위해 공격적 행위를 추구하 는 전략문화를 견지하고 있었음을 확인할 수 있었다. 이와 같은 러시아 와 북한의 전략문화에 대한 연구는 러-우전쟁의 원인을 규명하고 향후 한반도에서 북한의 공격적 도발 행위를 판단하는 데 설득력을 제공하며, 이에 대한 대비가 요구되고 있다.
본 연구는 가선집재시스템에서 벌도목을 견인 시작 지점에서 Yarder까지 안전하게 운반할 수 있는 최대 하중인 가선경로상의 허용반송량을 분석하여, 가선집재 작업에 필요한 의사결정을 지원하기 위한 목적으로 수행되었다. 이를 위해 허용반송량의 변화를 예측하는 모델을 구현하고, 가선집재시스템 구동에 주요 인자인 지형조건, Yader의 높이, 가선의 직경, 벌도목의 견인형태 및 작업방식에 대한 민감도 분석을 수행하였다. 분석결과, 가선 설치계획에 있어 오목한 지형을 선택하는 것이 안전성과 효율성에 중요한 영향을 미치는 것을 확인할 수 있었고 Yarder의 높이나 Wire rope의 직경, 벌도목의 견인형태 및 시스템의 작업방법과 같은 시스템을 구성하는 여러 요인에 의해 작업 생산량이 달라지는 것을 확인하였다. 이러한 결과는 가선의 설치경로에 대한 허용반송량 분석의 필요성과 시스템의 다양한 구동 요인에 대한 평가가 가선집재시스템의 국내 현장 적용 및 보급에 필요함을 보여준다.
해양공간계획(Marine spatial planning)은 해양의 합리적인 이용과 지속 가능한 해양 공간 활용을 위한 중요한 요소이다. 특히 어업활동 보호구역은 지속 가능한 어업을 위한 핵심 용도구역으로, 해양공간계획 경계 내에서 약 45.6%를 차지한다. 그러나, 현재 어업활동보호구역의 지정 과 평가는 미래 수요와 잠재적 가치를 충분히 반영하지 못하고 있으며, 중장기 계획 수립을 위한 보다 합리적인 평가 방법과 예측 도구가 필요한 상황이다. 이러한 문제를 해결하기 위해, 본 연구는 어업활동보호구역 내 주요 어종인 고등어, 갈치, 멸치, 참조기를 대상으로 어종 분포 예측을 시도하고, 현재 용도구역과의 비교를 통해 예측 도구의 가능성을 평가하였다. 한편, IPCC 6차 기후변화 시나리오(SSP1-2.6 및 SSP5-8.5)를 적용한 종분포 모델(MaxEnt)을 사용하여 미래 기후변화에 따른 어종의 이동 및 분포 변화를 분석한 결과, 고등어, 갈치, 참조기의 분포 면적은 현재보다 약 28~86% 증가했으나, 멸치의 분포 면적은 약 6~11% 감소했다. 이 결과를 바탕으로 주요 4종의 종풍부도 지도를 작성하였으며, 해양공간계획 경 계 내에서 ‘높음’으로 평가된 종풍부도 해역과 어업활동보호구역이 중복되는 비율은 약 15%, SSP1-2.6 시나리오에서 21%, SSP5-8.5 시나리오에서 34%로 증가하였다. 연구 결과는 향후 용도구역 평가나 유보구역 변경 시 과학적 근거로 활용될 수 있으며, 어종의 현재 종분포와 기후변화에 따 른 분포 예측을 통해 현재 용도구역 평가의 한계를 보완하고, 지속 가능한 유용 해양 자원의 이용을 위한 계획 수립에 기여할 것으로 판단된다.
이 연구는 초분광 영상으로 두 품종의 콩(청자 3호, 대찬)의 들불병을 진단할 수 있는 모델과 다중분광 영상센서를 개발하기 위해 수행되었다. 무처리구와 들불병 처리구에서 5 nm full width at half maximum (FWHM)으로 구성된 원시 초분광 중심파장들의 콩 식물 영역 반사율들을 추출하여 10 nm FWHM으로 병합한 후, t-test로 차이가 나타난 blue, green, red, red edge, NIR1 및 NIR2 각 영역에서 선정된 대표 밴드로 121개의 식생지수를 계산하였다. 식생지수를 입력변수로 support vector machine (SVM), random forest (RF), extra tree (EXT), extreme gradient boosting (XGB)의 머신러닝 기법과 shapley additive explanation 변수 선택 기법을 적용하여 들불병 진단에 가장 적절한 모델을 선정하고 사용된 식생지수와 파라미터를 나타내었다. T-test 결과 품종에 상관없이 blue 1개(420 nm), green 2개(500, 540 nm), red 1개(600 nm), red edge 2개(680, 700 nm), NIR1 2개(780, 840 nm), NIR2 1개(920 nm)의 총 9개 대표 밴드들이 선택되었고, 성능 평가를 통해 선정된 모델에 청자 3호의 경우 SVM모델(OA=0.86, KC=0.72, 10 VIs)이 선정되었으나 혼동행렬 분석 결과 정상오분류가 적은 RF모델이 선택되었다. RF모델(식 생지수 : RE/Blue, NSI, GDVI, Green/Blue, 파라미터 : max_depth=6, n_estimators=100)은 OA=0.81, KC=0.60, precision=0.86, recall=0.81, F1 score=0.80의 성능을 나타내었다. 대찬은 EXT모델(식생지수 : YVI, RE/Green, 2YVI, 파라미터 : max_depth=8, n_estimators=10)이 선정되 었고, OA=0.86, KC=0.72, precision=0.86, recall=0.86, F1 score=0.86의 성능을 나타내었다.
The walking-stick insects, Ramulus mikado, are outbreaks in several mountainous areas from 2020 to 2022. In recent, some population of the insect are showed rapidly decline in their abundance, while some of them are still maintained high population density. In worldwide, insects belonging to Phasmida are reported to outbreak in their habitats as mentioned above environments, but knowledge about outbreak pattern of the walking-stick insects is still lacking. In this study, we aimed which biological and environmental factors are related to wax and wane of the insect population. From 2022 to 2023, we studied host tree preferences in natural conditions, ecological stoichiometry in major host trees, overwintering ecology of R. mikado eggs, and infection rate by entomophathogenic fungi during growing season.
As interactive marketing devices that serve as proximity-marketing tools, AI-powered voice assistants (VA) provide consumers with highly innovative convenience, which in turn fosters consumer–brand relationships (Wang, 2021). This research aims to explore the role of AI-powered VAs as a positive technology that offers consumers a sense of positive experiences, thus contributing to building a consumer-brand relationship. Based on the positive technology paradigm and transformation of flow strategy, this research conducted a 2 (locus of agency: high, machine-centric vs. low, human-centric) by 2 (brand image and voice congruency effect: incongruent vs. congruent) between-subjects experimental design. Then, ANOVA and structural equation modeling (SEM) analysis were conducted to explain how perceived control, flow, and happiness induced by the interaction with brands’ AI-powered VAs lead to the formation of brand loyalty under the moderating influences of brand image and VA’s voice congruency. A total of 316 participants were recruited via Prolific. The ANOVA analysis highlights the importance of user-centric agency, as people tend to desire to control their environment (White, 1959). Further, the results suggest that the congruency between brand image and VAs also leads people to positive reactions, as it improves their comfort and control (Rodero, Larrea, & Vázquez, 2013). SEM analysis results found that perceived control was a crucial factor that led participants to flow experience (Ghani et al., 1991). Further, this study found that perceived control could lead to a much broader aspect, such as an increase in happiness. Therefore, the overall study findings support the potential of AI-powered VAs as a positive technology. This research contributes to human-machine interaction, positive technology paradigm, and VA literature. In addition, this study provides beneficial insights for marketers and app developers.
Recently, attention has increasingly been paid to the heterogeneity of firm performance. Some firms seem to extensively outperform their rivals not only in terms of productivity but also regarding sales, returns on investment, etc. Importantly, the chasm between the superstar firms, most successful group of firms in an industry, and their peers has been widening especially in the 21st century (Van Reenen, 2018).Superstar firms’ impacts on economies have gained a great deal of attention in the economics and policy literature. Understanding what helps firms become superstars can guide policy and management but requires further research and input from the management literature. This paper brings the topic of superstar firms to the management literature, develops a theory, and offers an empirical view of the drivers of superstar firms.
Measuring service quality and related key dimensions has been an important problem in Marketing. In this research, we would introduce a smart methodological framework to efficiently identify refined, key sentiment dimensions for measuring the service quality using both traditional survey and unstructured online reviews (natural survey). The proposed framework consists of three parts: (1) steps for preprocessing the unstructured reviews to generate attribute-level sentiments for independent variables (2) Bayesian regression to efficiently identify key groups of correlated attributes and (3) post-hoc analysis for identifying dimensions from the selected groups of correlated attributes and predicting dimension-level effects. Note, the first part of the framework (i.e., preprocessing) is not required for analyzing traditional surveys. Our framework provides two sets of complementing results such as attribute-level effects under the identified dimensions and aggregate dimension-level effects. In the first application study to traditional SERVQUAL data, we successfully validated the proposed framework by comparing the results between our framework and three commonly used existing methods of regression, lasso regression, and factor analysis. In the second empirical application study with the online reviews from a major game review website, STEAM platform, we found that our framework provided a significantly reduced number of key dimensions which were surprisingly efficient for predicting and explaining the service quality ratings, compared with the same set of compared methods in the first study plus the topic model. In particular, with reviews of 2,825 games, three key dimensions of Mechanical playability, Fun in fantasy and Money for value were identified, and we also found that the Mechanical playability could be an important driver of game popularity.
The impact of firms' marketing communication on word of mouth (WOM) has been studied extensively in recent years, with a growing focus on electronic word of mouth (eWOM). The advent of the internet and the participatory web or Web 2.0 has dramatically changed the relationship between marketers and consumers, with consumers playing a more active role. However, there is a gap in understanding this area, including a lack of research on identifying specific groups of consumers that companies should focus on for eWOM marketing. Eye-tracking techniques have been suggested to address this issue, but these methods can be costly and rely on lab-based observations. Analyzing unstructured data from consumer-to-consumer interactions on social media is an underutilized approach in current marketing literature. The authenticity of eWOM is a highly valuable trait, but there can be a tension between commercial and communal norms, even in relatively informal settings like a blogger endorsing a product.
본 연구는 조직이 원격근무를 도입하고자 할 때 실질적으로 고려해야 할 사항들을 분석해 제안하려는 목적으로 실행되었다. COVID-19로 인해 확산된 원격근무는 생산성의 보전 및 일-가정 양립 등의 효용을 가져와 포스트 팬데믹 시대에서도 뉴노멀로 활용될 수 있다는 가능성이 타진되었다. 그러나 원격근무는 전염병으로 인한 위기 상황에서 주입적으로 실행되었을 뿐 그에 맞는 운영 방침이 정해지지 않아 기업들 의 효율적인 도입이 어려웠다. 기존부터 원격근무에 관련된 연구는 진행되고 있었다. 그러나 선행연구들 은 원격근무의 이론적인 방향성을 언급하거나 긍정적인 효과에 대한 기대점을 시사하는 내용이 주를 이루었고 원격근무를 도입하거나 개선하고자 하는 기업을 위해 정량적 기법을 활용하거나 구체적인 제도 수립을 위한 요인 제시에 있어서는 미흡한 상황이다. 이에 본 연구는 원격근무 도입 시 고려해야 할 핵심 요인을 도출하여 기업들의 원격근무 도입에 실용적이고 통합적인 관점을 제안하고자 하였다. 이를 위해 경영학계 교수 및 인사관리 전문가들로 구성된 패널을 대상으로 델파이 조사를 실시하였다. 델파이 연구 는 정립되지 않은 분야에서 방향성을 도출하기에 적합한 사회 연구 방법론이라고 할 수 있다. 따라서 델 파이에 관련된 선행연구를 따라 가장 적합한 방식으로 총 3차에 걸친 델파이 조사를 진행하였으며, 조사 결과 최종적으로 조직문화, 업무환경, 인적자원, 성과관리의 네 가지 영역에 걸친 16가지의 핵심 요인이 도출되었다. 본 연구는 원격근무와 관련된 명확한 가이드라인이 없는 상황에서 원격근무 도입 시 인사 관리자들이 실질적으로 고려할 수 있는 요인들을 체계화했다는 점에서 의의를 지닌다.
In this study, we evaluated the performance of phosphate-functionalized silica in adsorbing uranium and provided insights into optimizing the initial conditions of the uranium solution (concentration and pH), which are often overlooked in uranium adsorption studies. While most studies take into account the effect of pH on both the surface charge of the adsorbents and the dissolved speciation of uranium in solution, they often overlook the formation of solid phases such as β-UO2(OH)2 (cr) and UO3· 2H2O(cr), leading to an overestimation of the adsorption capacity. To address this issue, we considered the speciation of U(VI) calculated using thermodynamic data. Our findings suggest that it is reasonable to evaluate the adsorption performance at pH 4 and concentration below 1.35 mM. The formation of β-UO2(OH)2 (cr) starts at 23 μM (pH 5) and 1 μM (pH 6) and increases sharply with increasing concentration. To avoid interference from the formation of solid phases, experiments should be conducted at lower concentrations, which in turn require very small msorbent/Vsolution ratios. However, controlling small amounts of sorbent can be challenging, and increasing the volume of the solution can generate significant amounts of radioactive waste. We also used UV-vis spectra analysis to investigate the formation of solid phases. We found that a 100 mg L-1 uranium solution resulted in the formation of colloidal particles in the solid phase after 2.5 hours at pH 6, while at pH 4, no significant changes in absorbance were observed over 120 hours, indicating a stable ion phase. Based on these conditions, we obtained an excellent adsorption capacity of 110 mg g-1.