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In 2018, a bacterial disease complex composed of bleached spots and soft rot–blight on onion seedlings was observed in nursery beds in Changnyeong, a major onion-producing county in South Korea. Four bacteria isolated from the diseased lesions were identified: Pseudomonas viridiflava, Acidovorax avenae subsp. avenae, Pantoea ananatis, and Xanthomonas axonopodis, respectively. We referred to the four strains as a “bacterial disease complex” because they were isolated from the same sample with multiple symptoms. We examined the synergistic activity among the four strains to understand their relationships and roles. We monitored in vivo bacterial population density and disease progression after artificially inoculating the bacteria on onion seedlings at a temperature of 22 or 28°C. The disease pattern progressed sooner at 28 than at 22°C (by an average of 4 to 6 days). The rate of disease progression induced by inoculation of P. ananatis alone was consistent with that induced by coinoculation of P. ananatis with the other strains, regardless of the temperature (22 or 28°C). The in vivo growth of P. ananatis on onion seedlings was not different after inoculation alone versus together with the other strains. The rate of disease progression induced by P. viridiflava was similar when inoculated alone and when inoculated with other tree strains at 28°C, but disease progression induced by inoculation alone was slower at 22°C. The in vivo growth of P. viridiflava or X. axonopodis on onion seedlings decreased rapidly or gradually, respectively, when inoculated with the other strains. Coinfection with the other three strains had repression effects on the growth of P. viridiflava, a slight effect on X. axonopodis, and no effect on P. or A. avenae subsp. avenae in vivo. These results indicate that the strains coexist or interact antagonistically, rather than synergistically, depending on the conditions. These results were consistent with the results of the in vitro growth inhibition assay, in which P. viridiflava growth was inhibited by X. axonopodis or P. ananatis. These results also confirmed that X. axonopodis is present on bleached spots and P. viridiflava on soft rot–blight lesions, and that P. viridiflava and P. ananatis cause soft rot–blight but do not coexist. A. avenae subsp. avenae is a minor causative pathogen of bleached spots on onion seedlings, but it is not significantly affected by temperature and has no antagonistic or synergistic interactions with X. axonopodis.

There are many conflicts among online communities' users and there are diverse types of online communities which have their own conflict management. Also, there are many users who perceive their online communities useful both in their cyber and real lives. This study clarifies the effects of jargons and focuses on finding out whether there are considerable relationships among individual inclination, linguistic habits, and conflict management types to affect the user's intention to participate in communities. There are significant relationships among jargons, conflict managements, selfishness, and perceived usefulness. This study also explains whether the frequency usage of jargon in online communities would affect the types of management, perceived usefulness, and community members' participation. Moreover, it may be clear that online jargon effect community members' participation and perceived usefulness.

We evaluated and classified forty five onion cultivars according to bulb initiation, bulb and scale characteristics, minerals and organic compounds contents, and storage quality in South Korea during 2016/2017 and 2017/2018 growing seasons. Field experiment was conducted in randomized block design with three replications. Bulb initiation ranged from 153 days after transplanting (DAT, April 2) to 177 DAT (April 26). Fresh bulb weight (FBW) and bulb index (BI) were 285.5 ± 18.5 g/individual, 0.93 ± 0.05, respectively. Number of scales (NS), number of center (NC), and scale thickness (ST) were 7.6 ± 0.2, 2.3 ± 0.2, and 5.5 ± 0.2 mm/scale, respectively. Chroma and Lightness of bulb skin were 27.1 ± 1.9, 61.2 ± 2.3, respectively. Storage loss (SL) on December 12 was 19.4 ± 5.9%. Nitrogen (N), Carbon (C) and sulfur (S) contents were 1.36 ± 0.14, 37.9 ± 3.2 and 0.40 ± 0.06 mg kg−1 on a fresh weight basis. Total soluble solids (TSS) and total phenolics content (TPC) were 8.6 ± 0.6 °Bx, 164.8 ± 15.6 mg GE kg−1 on a fresh weight basis. Days from transplanting to bulb initiation was significantly positively correlated with bulb height, NC, dry matter, N, C, S, TSS, TPC, total flavonoids content (TFC) etc., while it was negatively correlated with rot loss and SL. Dry matter content was significantly positively correlated with N, C, S, TSS, TPC, TFC etc., while it was negatively correlated with SL. Storage loss was negatively correlated with N, S, Potassium and TSS. Dendrogram of agglomerative hierarchical clustering for the forty five cultivars based on bulb initiation, bulb and scale characteristics, and bulb minerals and organic compounds contents classified five cultivar groups. Cluster 1 featured the earliest bulb initiation and the greatest SL. Cluster 2 featured the fewest NS and NR, and the thickest ST. Cluster 3 featured the greatest FBW, and the most NS and NC. Cluster 4 featured the greatest BI and the thinnest ST. Cluster 5 featured the lowest SL, and the highest minerals and antioxidant compounds contents. This information should be helpful for onion growers to decide onion cultivar and for onion breeders to promote new cultivars depending on their purpose.

This study evaluated the performance of 55 intermediate-day onion cultivars (Allium cepa L.) in southeastern Korea, and clustered the cultivars based on bulb maturity and marketable bulb yield (MBY...

The emission characteristics of mobile air pollution sources belonging to the non-road sector have yet to be thoroughly investigated, especially when compared to those of on-road vehicles. Hence, the present study employed an engine dynamometer to evaluate the emissions of a diesel engine complying with Tier 3 standards during various driving modes (KC1-8, NRSC, and NRTC) and a portable emissions measurement system (PEMS) to assess those of two excavators, one complying with Tier 3 and the other with Tier 4 standards, during real-world working and driving conditions. The characteristics and chemical composition of the emitted regulated pollutants (carbon monoxide (CO), non-methane hydrocarbon (NMHC), nitrogen oxide (NOx), and particulate matter (PM)) and hazardous air pollutants (HAPs), e.g., volatile organic compounds (VOCs), aldehydes, and polycyclic aromatic hydrocarbons (PAHs), were then determined. For the regulated pollutants, NRTC mode generated the highest emissions owing to the rapid changes in engine load and speed during transitions. As a result of the after-treatment systems, which utilized a diesel oxidation catalyst (DOC) and selective catalytic reduction (SCR), CO, NMHC, and NOx emissions from the Tier 4-compliant excavator were lower than those from the Tier 3-compliant diesel engine and excavator. The operating conditions of the diesel engine and construction equipment as well as the after-treatment systems significantly affected the composition of the non-methane volatile organic compound (NMVOC) emissions, which were dominated by alkanes that comprised 23 detected species. Sampling the particle-phase PAHs, we found phenanthrene, fluoranthene, and naphthalene; furthermore, we estimated the concentrations of the gas-phase PAHs with models to obtain the total PAH concentrations. Formaldehyde, which contributed the largest fraction of the aldehydes, was more abundant than the other species. Thus, emissions from non-road sources, including construction equipment, must be controlled because of the considerable health risks from pollutants such as formaldehyde and benzene. Our results will aid in the establishment of a national emission inventory for HAPs.

Gasoline direct injection (GDI) engines emit less carbon dioxide (CO2) than port fuel injection (PFI) engines when fossil fuel conditions are the same. However, GDI engines emit more ultrafine particulate matter, which can have negative health effects, leading to particulate emission regulations. To satisfy these regulations, various studies have been done to reduce particulate matter, and several studies focused on lubricants. This study focuses on the influence of lubricant on the formation of particulate matter and its effect on particulate emissions in GDI engines. An instrumented, combustion and optical singe-cylinder GDI engine fueled by four different lubricant-gasoline blends was used with various injection conditions. Combustion experiments were used to determine combustion characteristics, and gaseous emissions indicated that the lubricant did not influence mixture homogeneity but had an impact on unburned fuels. Optical experiments showed that the lubricant did not influence spray but did influence wall film formation during the injection period, which is a major factor affecting particulate matter generation. Particulate emissions indicated that lubricant included in the wall film significantly affected PN emissions depending on injection conditions. Additionally, the wall film influenced by the lubricant affected the overall particle size and its distribution.

The reactivity controlled compression ignition (RCCI) combustion has the potential to simultaneously reduce the NOX and PM emissions and maintain combustion performance even when injection timing is advanced. Because intake air temperature is an important factor affecting the reactivity of fuels, it is necessary to study optimized fuel supply ratios according to the intake air temperature. Therefore, the purpose of this study was to analyze combustion and exhaust characteristics in relation to the fuel supply ratio, injection timing, and intake air temperature. In this study, ethanol was injected into an intake port; increasing the ethanol supplied ratio increased the ignition delay. Thus, the net indicated mean effective pressure (IMEPnet), compared with conventional diesel combustion, increased from 4.14 to 4.90 bar for the advanced injection timing (BTDC 27°). In addition, because the combustion period was lengthened and combustion temperature lowered, the NOX emission decreased (19.1 → 2.7 g/kWh); however, the THC (1.1 → 2.5 g/kWh) and CO (5.2 → 10.1 g/kWh) emissions increased. Moreover, burning an homogeneous mixture of ethanol decreased the particulate matter emission from 74 to 45 μg/m3. However, under high intake air temperature conditions, the effect of ethanol ratio on ignition delay was small. Therefore, the injection timing at which the maximum IMEPnet occurred was retarded. In addition, as the intake air temperature increased, the THC and CO emissions decreased and that of NOX increased.

This study evaluated the effects of a nonwoven polypropylene (NPP) covering during overwintering with different mulch types and transplant times on bulb onion growth and yield of intermediate-day onions (Allium cepa L.) during the 2015/2016 and 2016/2017 growing seasons. Field experiments were conducted using a split-split plot design with three replicates. Treatments included main plots containing different mulch types (transparent plastic mulch, black plastic mulch, or bare ground), subplots with different transplanting times (20 Oct., 5 Nov., and 20 Nov.), and sub-subplots containing two onion cultivars (Sunpower and Katamaru). NPP was used to cover all plots on 1 Dec., and it was removed on 28 Feb. Mean daily air temperatures during transplanting and root establishment were 2.6 °C higher during the 2015/2016 growing season compared with the 2016/2017 season. NPP covering on bare ground increased soil temperature by 2.1 °C compared with no treatment. Soil water potential with transparent and black mulches and NPP continued to be more than −10 kPa until early March. Number of leaves, and root and leaf weight were significantly greater during the 2015/2016 growing season than during the 2016/2017 growing season; there were also significantly greater for onion plants grown with transparent plastic mulch than for those grown with black plastic mulch or no mulch on 4 Apr. and 5 May. Marketable bulb yield was lower during 2015/2016 (32.0 Mg·ha−1) than during 2016/2017 (38.5 Mg·ha−1); this was due to the increased unmarketable bulb yield, with 33.2 Mg·ha−1 bolters and 3.9 Mg·ha−1 doubled bulbs during 2015/2016 compared with 3.9 Mg·ha−1 bolters and 0.3 Mg·ha−1 doubled bulbs during 2016/2017. Marketable bulb yield of ‘Katamaru’ (38.9 Mg·ha−1) was greater than that of ‘Sunpower’ (31.6 Mg·ha−1). Marketable bulb yield increased with later transplanting times, and onions grown with black plastic mulch achieved the highest bulb yield (43.0 Mg·ha−1), followed by transparent mulch (34.7 Mg·ha−1) and no mulch (28.0 Mg·ha−1). When the temperatures from early November to early December were similar to the 30-year average temperatures, marketable bulb yield could increase with the NPP covering, especially for onions grown with black plastic mulch or no mulch when transplanted from late October to early November.

In general, recent certification procedure for regulatory emission limits is used to the standard test cycles in the laboratory under standardized operating conditions. But, it is proving that the real driving emissions (RDE) of vehicles highly exceed the standard emission limits. In order to tackle this problem, RDE regulation has been proposed with the Potable Emissions Measurement Systems (PEMS). In present study, the PEMS (Portable Emissions Measurement System) equipment, which consists of an exhaust gas flow meter, an exhaust gas sampling device, an exhaust gas analyzer, an OBD data acquisition device, GPS and ambient air sensors, and power supplying device, is installed on 17 test vehicles (Euro 6) sold in Korea currently. And two test driving routes (Route A and B) under 3rd RDE package were developed to include Seoul into urban driving due to reflecting representative traffic and road conditions in Korea. In results, the average NOx emissions of most test vehicles approximately exceeded 6.6 times the emission limit on test routes. Additionally, the on-road NOx emissions of test vehicles by applying SCR during the same trip were not relatively different based on the ambient temperatures. With respect to most test vehicles, the CO2 emissions in the urban section are generally higher than those in the total trip.

Euro 6 standards impose stringent nitrogen oxide (NOx) emission limits on diesel cars. NOx emissions are significantly different between Euro 6 diesel cars and the previous standards in real-world driving. In this research, the NOx concentrations of Euro 6 diesel engines during real-world driving were studied considering various factors. Real driving emission (RDE) tests were conducted using vehicles equipped with portable emissions measurement systems. Urban, rural, and motorway test routes were utilized. Road environment, atmospheric, and after-treatment performance factors were collected in each case. An artificial neural network was used for evaluation using RDE test data and various statistical parameters. It was found that the proposed method predicted the pollutant emissions effectively. Lastly, the relative importance of each predictor was derived, and the NOx concentrations were analyzed. These approaches provide accurate emission information for an environmental effect evaluation that reflects more realistic road conditions.

This study analyzed the characteristics and distribution of emissions from diesel vehicles that are sold in Korea and satisfy the Euro-6 standards, according to after-treatment systems. To identify the emission distribution of diesel vehicles according to after-treatment systems, results of the certification tests conducted on 266 vehicle models were examined. Results of the certification tests on 86 vehicle models that were manufactured based on the standards for RDE after 2017 were examined according to the engine displacement and power. The emission characteristics of six vehicle models equipped with different types of after-treatment systems were verified through certification tests in the New European Driving Cycle and Worldwide Harmonized Light Vehicle Test Procedure modes and RDE tests, according to the after-treatment systems. Specifically, a chassis dynamometer and an emission analyzer were used in the certification test modes; a portable emissions measurement system was used in the RDE test. The results indicated that the amount of NOx emissions from diesel vehicles has been constantly decreasing since 2017 due to the implementation of standards for RDE and advancements in after-treatment systems. Furthermore, it was found that selective catalyst reduction systems must be installed in vehicles to satisfy Euro-6 standards for permissible emissions on real-roads.

This study used emission certification data for vehicles that met Korea's Euro-6 emission standards after 2018. It was analyzed that the distribution of nitrogen oxide (NOX) emission in accordance with the type of after-treatment system under cold and hot start conditions by classifying domestic and imported cars. In addition, the relationship between electronic control unit (ECU)/dosing control unit (DCU) signals and exhaust emissions were analyzed under NEDC and WLTP driving mode conditions. Three models of vehicles equipped with different after-treatment systems were selected among the vehicles subject to the 2019 real road driving test for this study. And it was acquired that ECU and DCU signals, which are expected to be related to emissions as well as emissions. In order to satisfy Euro-6, the LNT + SCR after-treatment system was applied to more than 76% of vehicle models. Among ECU signals, there was a direct relationship between the accelerator pedal and the EGR valve opening degree, and there was a deviation depending on the driving mode. Among the DCU signals, the catalyst temperature, urea-water injection quantity, and injection timing are controlled in accordance with the NOX emission measured by the sensor. In the future, it is necessary to analyze the correlation between the ECU signal and the DCU signal to derive a factor that can be used as a measure to suspect defeat devices.

The purpose of this study is to investigate combustion and exhaust emissions characteristics by applying various split-injection strategies in order to determine the optimal injection that improves fuel efficiency and reduces exhaust emissions, compared with single-injection combustion. The split-injection strategies, such as the change of injection pressure, injection timing, and injection interval, were applied to single-cylinder diesel engine. From the analysis of the experimental results, it was revealed that, when the injection pressure was increased without changing the injection timing in split injection, indicated mean effective pressure (IMEP) and brake mean effective pressure (BMEP) decreased and brake specific fuel consumption (BSFC) deteriorated, owing to the increase of dwell duration. The increase of injection interval induced deterioration of BSFC and caused an increase in NOx and HC emissions with significant reduction in CO and soot emissions. On the other hand, the retardation of injection timing with a fixed injection interval caused an improvement of the BSFC, and a decrease in NOx, CO, and HC emissions. However, soot emission increased. According to the analysis, a short injection interval and injection timing around top dead center (TDC), with not too high injection pressure, improve the BSFC and emission characteristics in split-injection diesel combustion.

Development, availability and users’ participation in the information service of agricultural food sector is slower than that of other sectors in Korea. This phenomenon comes from the lack of development strategies and comparative analyses with other sectors, as well as the agricultural food industry’s own characteristics which is developed based on the offline market. In this research, we will discuss about how to improve the public information service of agricultural food sector based on the example of establishing service improvement strategy by the most representative Okdab. In this research, we have drawn the following implications for development strategy of Okdab service based on three core keywords derived from benchmarking KOSIS. Three core subjects for upgrading public information service are ‘analysis information with expertise and differentiation,’ ‘user cooperation-oriented platform,’ and ‘intuitive nd effective UX,’ and to strength B.I. as an integrated information service of agricultural food sector, we need to identify the users’ satisfaction and needs for the existing service, establish an optimized operating strategy on a short-term, mid-term and long term bases, and implement them in a positive way. Based on this positive action, it can become a trustworthy information service for the users, and we can expect the improvement of the users’ recognition for its consistent usability and efficiency.

This study aimed to evaluate the effect of years and different locations, beef cattle manure compost (BCMC) and mixed oilseed cake (MOC) application rates on bulb and scale characteristics, nutrien...

The cholesterol ester transfer protein (CETP) inhibitor dalcetrapib has been under evaluation for its potential to prevent cardiovascular (CV) events for almost two decades. The current clinical development program, representing new advances in precision medicine and focused on a genetically defined population with acute coronary syndrome (ACS), is supported by a large body of pharmacokinetic and pharmacodynamic data as well as substantial clinical experience in over 13,000 patients and volunteers. Dalcetrapib treatment of 600 mg/day produces significant inhibition of CETP activity, and has been utilized in phase II and III studies, including CV endpoint trials. Numerous studies have investigated the interactions between dalcetrapib and most drugs commonly prescribed to CV patients and have not demonstrated any clinically significant effects. Evaluations in patients with renal and hepatic impairment demonstrate a greater exposure to dalcetrapib than in the non-impaired population, but long-term clinical studies including patients with mild to moderate hepatic and renal dysfunction demonstrate no increase in adverse events. Safety pharmacology and toxicology studies as well as the clinical safety experience support the continuing development of dalcetrapib as an adjunct to 'standard of care' for the ACS population. This article provides a full review of the pharmacokinetics, as well as pharmacodynamics and pharmacology, of dalcetrapib in the context of a large clinical program.

It was recently reported that the Cmax and AUC of rosuvastatin increases when it is coadministered with telmisartan and cyclosporine. Rosuvastatin is known to be a substrate of OATP1B1, OATP1B3, NTCP, and BCRP transporters. The aim of this study was to explore the mechanism of the interactions between rosuvastatin and two perpetrators, telmisartan and cyclosporine. Published (cyclosporine) or newly developed (telmisartan) PBPK models were used to this end. The rosuvastatin model in Simcyp (version 15)'s drug library was modified to reflect racial differences in rosuvastatin exposure. In the telmisartan-rosuvastatin case, simulated rosuvastatin CmaxI/Cmax and AUCI/AUC (with/without telmisartan) ratios were 1.92 and 1.14, respectively, and the Tmax changed from 3.35 h to 1.40 h with coadministration of telmisartan, which were consistent with the aforementioned report (CmaxI/Cmax: 2.01, AUCI/AUC:1.18, Tmax: 5 h → 0.75 h). In the next case of cyclosporine-rosuvastatin, the simulated rosuvastatin CmaxI/Cmax and AUCI/AUC (with/without cyclosporine) ratios were 3.29 and 1.30, respectively. The decrease in the CLint,BCRP,intestine of rosuvastatin by telmisartan and cyclosporine in the PBPK model was pivotal to reproducing this finding in Simcyp. Our PBPK model demonstrated that the major causes of increase in rosuvastatin exposure are mediated by intestinal BCRP (rosuvastatin-telmisartan interaction) or by both of BCRP and OATP1B1/3 (rosuvastatin-cyclosporine interaction).

This study investigated the effects of various ethanol-gasoline blends on the hazardous air pollutants (HAPs) emissions from a wall-guided direct injection passenger vehicle. The fuel economy (FE) as well as regulated and unregulated gaseous emissions was evaluated on a chassis dynamometer using the federal test procedure (FTP-75) mode. Five fuels with varying ethanol contents of E0, E10, E30, E50, and E85 were prepared by blending ethanol into commercial gasoline on a volumetric basis and were analyzed each fuel specification. The engine control schemes of fuel injection quantity for various ethanol blends were adjusted to optimize the engine starting capability, vehicle drivability and emissions performance. The FE of the E85 fueled vehicle decreased by 29% relative to gasoline fuel due to the low energy content of ethanol. Blending ethanol into gasoline produced a dramatic decrease of particulate emission, because pure ethanol has no aromatic compounds and carbon content lower than that of gasoline. As a result, nano-particles were rarely emitted in the vehicle tests of fuels with more than 30% ethanol. Carbonyl compounds emissions, which originate from partial oxidization or incomplete combustion of ethanol, also rose sharply as the ethanol content increased, while volatile organic compound (VOC) emissions were reduced considerably with medium- and high-ethanol formulations due to the lower proportion of aromatic components in these fuels.

Despite the wider introduction of the buy online and pick up in-store (BOPS) service by retailers, research on BOPS is still sparse, especially those from the consumer perspective. This paper employs the scenario-based factorial survey method to investigate how the perceived characteristics of innovation and the perceived risk of online shopping influence the consumers’ intention to use BOPS while also considering the moderating effects of situational factors (location convenience) and product type (involvement). Our findings indicated that the consumer perceptions of relative advantage, complexity, compatibility, and risks involved in online shopping are important antecedents to intention to use BOPS, and that these relationships were significantly moderated by locational convenience and product involvement. The implications of the findings and suggestions for future research are discussed in detail.