The Challan instrument is a solar full-disk imaging spectroscopic telescope planned to be installed at three sites with a 120-degree longitudinal difference, enabling continuous 24-hour observations of the Sun. It will take data every 2.5 min with a spatial resolution of 2–3′′ and a spectral resolving power (R) of >43,000 in Hα and Ca ii 8542 Å bands simultaneously. Challan is composed of two modules, each dedicated to a specific waveband. This modular design is beneficial in minimizing the scattered light and simplifying the structure and engineering. The primary scientific goal of Challan is to investigate solar flares and filament eruptions. It is also expected to detect small-scale events in the solar chromosphere. In 2025, Challan will be installed at the Big Bear Solar Observatory for test observational runs, followed by scientific runs in 2026.
말라리아는 Anopheles 모기들에 의해 전파되며, 대한민국에서는 코로나 팬데믹 기간 동안(2020~2022) 약 200~300명대의 말라리아 환자가 발생하였으나, 지난 2023년에는 그 수가 폭증해 약 800명의 환자가 발생하였다. 현재까지 모기를 방제하기 위한 가장 효율적인 수단은 살충제를 사용한 방제이나, 지속적으로 이러한 화합물에 노출된 모기 개체군은 살충제에 저항성을 갖게 되는 것으로 알려져 있다. 이에 본 연구에서는 대한민국의 주요 말라리아 발생 지역인 비무장지대 부근 및 이외 지역인 용산, 평택, 오산에서 채집을 진행하였으며, 채집된 An. sinensis에 대해서 살충제 저항성과 관련되어 있다고 알려진 유전자인 acetylcholinesterase-1(ace-1)와 voltage-gated sodium channel(vgsc) 영역에 대한 저항성 돌연변이 보유 여부를 각각 확인하였다. 실험 결과 채집된 모든 지역에서 G119S(ace-1), L1014F,C(vgsc) 돌연변이가 발견되었으며, 그 빈도는 계절과 장소에 따라 차이를 나타내었다. 본 실험 결과는 향후 말라리아 감염 억제를 위한 매개체 연구에 활용될 수 있을 것으로 기대된다.
A facile and efficient method was developed to prepare highly stretchable and conductive graphene conductors with wrinkled structures by the mechanical stretching and shrinking of elastomeric substrates, in which graphene inks were printed on a prestretched elastomeric substrate. Stretchable and exfoliated graphene inks were prepared by mixing graphite and Ecoflex in a shear-assisted fluid dynamics reactor. The resultant graphene conductor exhibited excellent stretchability at 150% strain and high electrical conductivity of 64 ± 1.2 S m− 1. The resistance of the conductor did not change in bent, twisted, and stretched states. The resistance did not change during 10,000 cycles of stretching/releasing, with a maximum strain of 150%. Based on the graphene conductor, a stretchable conductometric sensor with a two-electrode configuration was fabricated to measure impedance changes at different concentrations of electrolyte ions. This sensor exhibited a good and linear sensitivity curve (298.61 Ω mM− 1, R2 = 0.999) in bent and stretched states.
The effects of supplementing ESP-FM (Erythrobactor sp.), freshwater Chlorella (Chlorella sp.), and baker’s yeast (Saccharomyces cerevisiae) on the nutritional value and mass production of Moina macrocopa, which is used as a live feed for fish fry production, was investigated. Consequently, the effects of feeding the enriched M. macrocopa to the nutritional composition of larval rockfish (Sebastes schlegel) and carp (Cyprinus carpio) was also investigated. Maximum density of M. macrocopa was reached within 15-21 days after inoculation (0.5 to 22 individual/mL), at various temperatures, and either decreased or remained almost constantly thereafter. Protein content and amino acids composition of M. macrocopa were found to be influenced by their respective diets while lipid and ash contents did not considerably change. M. macrocopa fed with baker’s yeast were low in n-3 HUFA content, and those fed on the freshwater chlorella were high in the 18:2n-6 and 18:3n-3 HUFA content, and in cultures treated with ESP-FM were high content in n-3 HUFA. The utilization of M. macrocopa as a substitute fish feed for carp and rockfish showed the enrichment nutritional content.
Retailers procure private labels from several sources including national brand manufacturers, dedicated private label manufactures (often overseas or regional), and own manufacturing facilities.2 In the first case, the supplier utilizes its expertise and excess capacity to supply PLs. In the other two cases, the suppliers are dedicated to manufacturing PLs for single or multiple retailers. Consumers generally consider PLs as value substitutes of the corresponding national brands. As private labels become proliferated, more retailers are introducing premium PLs that oftentimes replace marginal national brands. It is natural to assume that the PL sourced from the excess capacity of the NB manufacturer is identical to the corresponding NB except for the branding and packaging. In this paper, we examine a retailer’s problem of tiered PL sourcing, in which a premium PL is supplied such a NB manufacturer (dual brander), and an economy PL is supplied by a dedicated PL supplier. We decompose the value of a product into three components: the NB’s brand equity, the retailer’s reputation, and the intrinsic quality of the NB. In this distribution channel, the NB’s wholesale and retail prices are determined by the traditional bilateral Nash game. However, the premium PL’s transfer price is determined through a profit-sharing negotiation between the channel members. Based on this game scenario, we build a model of price competition, given the quality, brand equity, and retailer reputation parameters, in order to examine strategic implications of the parameters to the equilibrium prices. In our bilateral pricing game, the NB manufacture and the retailer play a Nash pricing game, augmented by a profit sharing negotiation for the premium PL. In the negotiation process, the retailer’s negotiation power over the NB manufacture is reflected in the ratio of incremental profits from the premium PL. From an equilibrium-negotiation solution, we derive profit implications of each of the value components as well as the negotiation power of the retailer. Among several findings, the most interesting takeaway is that, even if the retailer holds a strong negotiation power, it is optimal for the retailer to leave some chips on the table for the NB manufacturer during the transfer pricing negotiation.