Herbicides have consistently contributed to yield increases in crop production for many decades however, those same herbicides are facing the loss of effectiveness because of the rapid spread of weed resistance. Since the first instance of herbicide resistance to triazine herbicides over 50 years ago, resistant biotypes have been observed to the major herbicides numbering more than 150 different weed species due to excessive use of single mode of action (MoA)treatments combined with limited crop rotation practices. In the US, the most well-known broad-spectrum herbicide used in major crops, glyphosate is facing huge challenges due to the appearance of many resistant weed species. The consequences of the loss of effectiveness of the current herbicide choices, coinciding with an increasing world population with improved living standards, is beginning to present a severe constraint on food security globally. Unfortunately, the agriculture industry has been unable to find any new mechanism in the last 30 years. The absence of choices of novel active ingredients along with the increased costs of developing new entities is forcing the industry to rely on older modes of action which, with limited application, means lower annual yields of the major crops as the number of resistant weed species increases. The Chemical Genomics group in FMC Agricultural Solutions Discovery has been building ‘Chemistry to Gene’ (C2G) capability to identify new MoAsby applying chemical genomics tools. We have recently discovered that compounds described in WO2017075559A1, are potent selective herbicides with novel action that control many grasses. As a result of knowledge of the mechanism of this area of chemistry, we have extended the work to include a ‘Gene to Chemistry’ (G2C) approach to provide new structural starting points for more synthesis projects.

Growing resistance to insecticides, especially pyrethroids, poses an increased risk for insect control world-wide. Thus, alternative compounds are urgently needed. Accordingly, my laboratory has been investigating synthetic materials, as well as natural products, which are an attractive source of new chemistries. We have examined the insecticidal and synergistic activity of new compounds using Drosophila melanogaster and the mosquitoes Aedes aegypti and Anopheles gambiae as model insects. In addition, we have also been investigating the modes of action of experimental molecules in various physiological preparations. Natural product research included thymol, which was toxic to Ae. aegypti adults at doses (3-50 μg/mg) similar to published toxicities for the cabbage looper larvae, Trichoplusia ni. On homomultimeric Anopheles gambiae GABA receptor-chloride channel complex expressed in Xenopus laevis oocytes, thymol acts as a positive allosteric modulator, increasing the potency and maximal effectiveness of applied GABA, consistent with the sluggish paralysis it elicits in exposed insects. Other studies investigated matrine; a bioactive component extracted from Sophora flavescens that is used as the main ingredient in Chinese bio-pesticidal products. Matrine caused flaccid paralysis in headless fourth instar larvae of Ae. aegypti (50% paralysis in 5 hours at 8 ppm) and was toxic to adult females by contact (topical LD50 = 258 ng/mg). Adult toxicity was increased about 2-fold by pretreatment with the mono-oxygenase inhibitor, piperonyl butoxide. Interestingly, this compound was much less effective on D. melanogaster in either glass contact or feeding bioassays. Adult mosquito knockdown was rapid, with little or no expression of hyperactivity or hyperexcitability. Matrine (ca. 1 mM) had effects similar to thymol on expressed An. gambiae GABA receptors, and reduced EPSP amplitude at the Musca domestica neuromuscular junction, without any evidence of neuroexcitation or membrane depolarization. These physiological actions are sufficient to explain the whole animal intoxication by matrine, but require relatively high concentrations to manifest themselves. Other studies tested a series of potassium channel blockers, including 1-((2-chlorophenyl)diphenylmethyl)-1H-pyrazole (TRAM-34), 11-dansylaminoundecanoic acid (DAUDA), and 5-hydroxydecanoic acid (5-HDC) as insecticides and synergists of pyrethroids. We also evaluated the action of these compounds in patch clamp recordings of engineered HEK cells expressing Anopheles gambiae Kv2.1 channels. Patch clamp studies revealed that fatty acid compounds without functional groups in the alkyl chain (e.g., decanoate, DAUDA) yielded a more potent blocking action on Kv2.1 currents than substituted fatty acids (e.g., 5-HDC). Also, in comparison to 2-methoxy-N-((1-phenylcyclopentyl)methyl)benzamide (2S-65465), a known Kv2 channel blocker (IC50 = 100 nM), decanoate and DAUDA were 6-fold and 12-fold less active, respectively, as blockers of potassium current. TRAM-34 was the least potent inhibitor tested in patch clamp studies (IC50 = 30 uM). When tested on D. melanogaster CNS, the compounds typically gave an initial increase in firing rate, followed by a decrease, both effects at micromolar concentrations. Various toxicity assays showed the same potency ranking as that obtained through patch-clamp recordings, indicating a possible connection between channel block and whole organism effects. In order to possibly improve the insecticidal activity of the fatty acids, we synthesized derivatized analogs (e.g., methyl esters) presumed to better penetrate the cuticular barrier, but activity did not improve. Finally, in contrast to a published patent, we found that fatty acids did not show much synergism with pyrethroids. The implications of this work for resistance management will be discussed.

In this study, we investigated the dynamic stability of the system and the semi-analytical solution of the shallow arch. The governing equation for the primary symmetric mode of the arch under external load was derived and expressed simply by using parameters. The semi-analytical solution of the equation was obtained using the Taylor series and the stability of the system for the constant load was analyzed. As a result, we can classify equilibrium points by root of equilibrium equation, and classified stable, asymptotical stable and unstable resigns of equilibrium path. We observed stable points and attractors that appeared differently depending on the shape parameter h, and we can see the points where dynamic buckling occurs. Dynamic buckling of arches with initial condition did not occur in low shape parameter, and sensitive range of critical boundary was observed in low damping constants.

Now that problems with force-based seismic design have been clearly identified, design is inclined toward displacement-based methods. One such widely used method is Direct-Displacement-Based Design (DDBD). Yet, one of the shortcomings of DDBD is considering higher-mode amplification of story shear, moments, and displacements using equations obtained from limited parametric studies of regular planar frames. In this paper, a different approach to account for higher-mode effects is proposed. This approach determines the lateral secant stiffness of the building frames that fulfill the allowable inter-story drift without exceeding the desired story displacements. Using the stiffness, an elastic response spectrum analysis is carried out to determine elastic higher-mode force effects. These force effects are then combined with DDBD-obtained first-mode force effects using the appropriate modal superposition method so that design can be performed. The proposed design procedure is verified using Nonlinear Time History Analysis (NTHA) of twelve planar frames in four categories accounting for mass and stiffness irregularity along the height. In general, the NTHA response outputs compared well with the allowable limits of the performance objective. Thus, it fulfills the aim of minimizing the use of NTHA for planar frame buildings, thereby saving computational resources and effort.

The purpose of this study was to investigate the structural relationship between environmental factors, personal factors, ease of use, usefulness and behavioral intention of delivery application by applying the extended Technology Acceptance Model (TAM). An online survey was conducted based on a self-administered questionnaire to a selected sample who had an experience of using delivery application at least once. The survey was conducted in September, 2017. The data obtained was analyzed using SPSS 24.0 for windows and AMOS 24.0. The findings of the study showed that among environmental factors, social influence had a significant effect on perceived usefulness and perceived ease of use and facilitating conditions had a significant effect on perceived ease of use only. Among personal factors, anxiety had a significant effect on perceived usefulness, while innovation had a significant effect on perceived ease of use. Both of perceived usefulness and perceived ease of use had a significant effect on behavioral intention. This study suggests the importance of environmental and personal factors for increase of behavioral intention of delivery application.

In the current study, we investigated the inhibitory activity of water soluble β-glucan from oat (Avena sativa) against various digestive enzymes such as α-glucosidase, sucrase, maltase and glucoamylase. Inhibition of these enzymes involved in the absorption of disaccharide can significantly decrease the post-prandial increase of blood glucose level after a mixed carbohydrate diet. The β-glucan had the highest documented rate of small intestinal sucrase inhibitory activity (2.83 mg/mL, IC50) relevant for potentially managing post-prandial hyperglycemia. Furthermore, we evaluated the effects of β-glucan on the level of post-prandial blood glucose in animal model. The post-prandial blood glucose levels were tested two hours after sucrose/starch administration, with and without β- glucan (100, and 500 mg/kg-body weight). The maximum blood glucose levels (Cmax) of β-glucan administration group were decreased by about 23% (from 219.06±27.82 to 190.44±13.18, p<0.05) and 10% (from 182.44±13.77 to 165.64±10.59, p<0.01) in starch and sucrose loading test, respectively, when compared to control in pharmacodynamics study. The β -Glucan administration significantly lowered the mean, maximum, and minimum level of post-prandial blood glucose at 30 min after meal. In view of the foregoing, it is felt that our findings suggest that β-glucan from oat serves to reduce post-prandial blood glucose rise secondary to slower absorption of glucose in the small intestine, via carbohydrate hydrolyzing enzymes inhibition.

대기오염에 대한 관심은 국내·외에서 점진적으로 상승하고 있으며, 자동차 및 연료 연구자들은 청정(친환경 대체연료) 연료와 연료품질 향상 등을 이용하여 새로운 엔진 설계, 혁신적인 후처리 시스템 등의 연구를 통하여 차량 배기가스 및 온실가스를 감소시키고자 노력하고 있다. 이에 본 연구에서는 각기 다른 차량기술이 적용된 휘발유, 경유, LPG를 연료로 사용하는 7대의 차량을 대상으로 국내·외에서 법적시험모드로 사용되고 있는 도심모드, 고속모드, 급가·감속, 에어컨사용 및 겨울철 특성을 반영한 저온모드에서 온실가스의 배출특성을 확인하고자 하였다. 사용연료에 관계없이 대부분의 온실가스는 저온인 Cold FTP-75 모드에서 가장 안 좋은 결과가 나타나는 경향을 가지고 있다. 각 차량별 온실가스 증가 요인으로는 가솔린 차량인 A차량(2.0 MPI)과 B차량(2.4 GDI)에서는 최고속 및 급가·감속 , 에어컨 사용 , 저온 조건의 순인데 비해 E차량(1.6 T-GDI)은 에어컨 사용, 최고속 및 급가·감속 , 저온 조건의 순이다. G차량 (LPLi)은 에어컨 사용 , 저온 , 최고속 및 급가·감속 조건의 순으로 가솔린 차량과 다른 특성을 가지고 있다. 경유 차량에 있어서는 A차량(2.0 w/o DPF)과 B차량(2.2 w/ DPF)은 최고속 및 급가·감속 , 에어컨 사용, 저온 조건의 순이었고, F차량(1.6 w/ DPF)은 저온, 에어컨 사용, 최고속 및 급가·감속 조건의 순으로 확인되었다. 따라서, 각 연료별로 배출가스 저감 기술을 다르게 적용하여야 효과적인 방법이라고 할 수 있겠다.

Theory of Earth’s free oscillation is revisited. Firstly, we summarized the underlying formulations, such as the equation of motion and its conversion into numerically integrable form and then explained computational procedures including the treatment of inner core-outer core boundary and core-mantle boundary, while the latter information has not been explicitly given in most publications. Secondly, we re-calculated the periods of Earth’s free oscillation modes (period >200 s) for PREM model. In doing so we acquired the values of modes missing in Dziewonski and Anderson (1981). As a case observation, one seismogram after 2011 Tohoku earthquake recorded at Daejeon, Korea (KIGAM seismic station) was briefly analyzed to identify free oscillation mode excitations on its spectra. The material in this article will be most clear guide for those on calculating the Earth’s free oscillation mode.

The combustion instability in a dual swirl combustor was investigated experimentally. The effects of thermal power and combustor length on combustion instability were evaluated. Pressure and heat release fluctuation were measured simultaneously. In a conventional combustor, the frequency was decreased with increasing combustor length and decreasing thermal power. However, it showed different results with a dual swirl combustor. In regime 1 where thermal power was relatively high, the results showed same tendency with a conventional combustor. In regime 2 where thermal power was relatively low, the frequency was almost constant with increasing combustor length. It was found that a beating phenomenon occurred with increased combustor length in regime 2 by measuring sound pressure fluctuation. By confirming that beating phenomenon occurs only in regime 2, it is considered that beating phenomenon is the dominant factor of combustion instability in regime 2. This beating phenomenon inside combustion chamber greatly affected to combustion instability. The reason of the beating phenomenon seemed to be the difference oscillating period between main flame and pilot flame.

Trophic associations of lepidopteran larvae have been formed from a long period of evolution. The larva of Oecophoridaecan keep being concealed with several strategies. They may be sheltered within a web or hidden under bark or deadwood, or inside leaves rolled by them. Sometimes they bore stem or trunk or burrow under bark or hide in soil. In addition,they can also be found in very diverse and specialized microhabitats. This study was to assess the ancestral characterstate of microhabitat and larva sheltering strategy within the phylogenetic relationship of Oecophoridae to understand theirevolutionary transition and the adaptation of larva to microhabitats using sheltering strategies. Also, it is to investigatethe historical biogeography and evolution of the family Oecophoridae and related higher taxa for understanding their globalradiation and distribution.

The stability of the steady Rossby-Haurwitz wave (R-H wave) in the nondivergent barotropic model (NBM) on the sphere was investigated with the normal mode method. The linearized NBM equation with respect to the R-H wave was formulated into the eigenvalue-eigenvector problem consisting of the huge sparse matrix by expanding the variables with the spherical harmonic functions. It was shown that the definite threshold R-H wave amplitude for instability could be obtained by the normal mode method. It was revealed that some unstable modes were stationary, which tend to amplify without the time change of the spatial structure. The maximum growth rate of the most unstable mode turned out to be in almost linear proportion to the R-H wave amplitude. As a whole, the growth rate of the unstable mode was found to increase with the zonal- and total-wavenumber. The most unstable mode turned out to consist of more-than-one zonal wavenumber, and in some cases, the mode exhibited a discontinuity over the local domain of weak or vanishing flow. The normal mode method developed here could be readily extended to the basic state comprised of multiple zonalwavenumber components as far as the same total wavenumber is given.

Recently, for efficiency increase of the wind turbine tower, turbine has been enlarged and installation location has been transferring to offshore. The importance of the support structure is emphasized when a wind turbine tower is installed on offshore. The support structure is influenced not only by the system operating loads but also by various marine condition loads. Accurate and safe design is essential because the connection between the support structure and the wind tower can be relatively fragile. In particular, the type of foundation pile and sleeve grout connection were adapted from DNV, API, and ISO that are typically used for wind towers, and they have been continuously studied by many researchers. However, the experimental results by researchers are different from the design equations, and it needs to modify the formula according to connection properties and material. Therefore, this study investigates the design equation presented in existing design criteria and the results of research conducted by existing researchers, and analyzes ultimate strength and failure modes.

Insecticidal crystal toxins from the bacterium Bacillus thuringiensis (Bt) kill insects via a complex mode of action resulting in the creation of cytolytic pores in the membrane of midgut epithelial cells. These toxins are expressed in transgenic cotton and maize which have been adopted worldwide to control lepidopteran pests while reducing dependence on chemical insecticides. However, insect resistance to Bt toxins is increasing in certain key pest species. Beginning with Heliothis virescens, genetic studies in Bt-resistant Lepidoptera and Coleoptera have found mutations in ABC transporters. Cry1A, Cry1C, Cry2A, and Cry3B toxins each appear to target a different member of the ABC superfamily. These studies confirm the essential role of ABC proteins in Bt toxin mode of action. It is proposed that ABC proteins assist in the insertion of the toxin into the midgut epithelial membrane, a crucial step for which the mechanism has not been known in detail. Properties of ABC transporters suggest strategies to increase efficacy of Bt toxins and to delay the evolution of Bt toxin resistance in target insect pests.

The purpose of this research is to explore the interaction patterns in an English (L2)-mediated Mandarin Chinese (L3) class (native-taught) for young monolingual Korean (L1) learners. Twenty-nine class videos were collected and transcribed into 152 pages of Chinese, English, and Korean for this analysis. The interaction patterns in the English-mediated Chinese classes were analyzed using the IRF framework of Sinclair and Coulthard (1975) and Tsui (1994). The results and discussions were integrated into four main patterns to interpret the English-mediated Chinese classes: 1) the native Chinese teacher’s needs for class assistance, 2) the students’ enthusiastic but inadequate use of English, 3) the students’ voluntary Korean scaffolding, and 4) the students’ class participation needs. On the one hand, this research has provided the students’ response to the teacher’s use of Chinese and English (in a foreign language-only environment), which is intended for a better understanding of a classroom with a trilingual teacher and monolingual students. On the other hand, the research has implications for understanding use of an L2 to facilitate an L3 classroom, particularly in the situation of using two foreign languages in one classroom.

The Infrared Camera onboard the AKARI satellite carried out spectroscopic observations with a grism mode named NG, whose wavelength coverage was 2.5{5.0 m. We reinvestigate the current ux calibration for the NG grism mode, with which calculated ux density implausibly decreases at 4.9 m especially for red objects due to the second-order light contamination. We perform a new spectral response calibration using blue and red standard objects simultaneously. New response curves which contain both the rst- and second-order light are able to separate each contribution consistently and useful for studies of red objects such as CO ro-vibrational absorption in active galactic nuclei.

This study compared aural and written modes of presentation for the two item types, to explore the effects of question/option presentation mode and item type on EFL learners’ listening comprehension performance and their perception. One hundred and fifteen Korean college students who were divided into three different proficiency groups participated in the study. The participants took a listening test which consisted of dialogue-completion and Q&A multiple-choice items in the aural and written modes, followed by a survey on their perceptions, and a stimulated recall interview. The results showed that the least proficient group was more critically affected by the mode than the other two groups. The least proficient group performed significantly better in the written mode than in the aural mode, while they received similar scores on the two item types. The major factors that caused the discrepancy among the groups were memory capacity in the aural mode and reading ability in the written mode. The implications and suggestions on listening test development are discussed.