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In August of 2011, a wilting disease of ginseng was observed at Bongwha, Gyeongbuk province, Korea. Affected plants initially show withering symptoms on leaves of ginseng. As the disease progresses, withering leaves spread downward, eventually encompassing the whole plant. Leaves lose vigor but remain pale green. Symptoms of roots were brown, and soft rots characterized by moist and watery decay of the whole ginseng root, which initiated as small brown, water-soaked lesions of hairy roots and enlarged to the entire roots. The causal organism isolated from the infected roots was identified as Serratia plymuthica based on its physiological and biochemical characteristics, by cellular fatty acid composition (GC-FAME), the utilization of carbon sources (BioLog System), and 16S rRNA sequence of the isolated bacterium were 99% homologous to those of Serratia plymuthica strains. Artificial inoculation of the bacterium produced the same brown or soft rot symptoms on the ginseng roots, from which the same bacterium was isolated. This is the first report of bacterial root rot caused by the Serratia plymuthica in ginseng in Korea. Serratia plymuthica has been used as antagonistic microorganism for biological control on several crop plants. But it was proved pathogen of ginseng at humid condition in this study.

A disease, supposedly caused by a virus, was observed from Insam (Panax ginseng) fields of Punggi in year 2006. It has long believed to be a physiological disorder. However, the incidence of the disease has increased every year. When several samples were observed under electron microscope, filamentous virus-like particles were observed. The nucleotide sequences of the virus were analyzed by RT-PCR with specific primer sets derived from the results of DNA chip. The results indicated that the disease was caused by Watermelon mosaic virus (WMV). It revealed that the result of the biological assay by the virus was different from that of WMV previously found in other crops. Therefore, this is the first report that WMV causes the disease in P. ginseng and the virus is named to be WMV-Insam.

Purpose: The purpose of this study is to understand the air traffic control (ATC) threats that cause airline pilots to commit errors during normal operations by identifying the prevalence of ATC threats to reduce ATC communication errors for safe flights. This study deals with ATC communication threats effect on the human performance of pilots through LOSA (line operations safety audit) implemented by Airlines. Methods: This study deals with ATC communication threats effect on the human performance of pilots through LOSA implemented by two domestic Airlines. Results: The prevalence of ATC threats shows that there are 60% of flights with at least one ATC-related threat. The frequent ATC threats have been identified as difficulties in understanding controller accents, changes of the runway, errors by ATC controllers, difficult clearance of altitude change and multiple clearances in one call. The most prevailing ATC threats occurred during the Descend, Approach & Land phase of the flight. Conclusion: In order to prevent accidents related with ATC and improve threats and human errors in the actual environment of pilots, it is necessary to identify and analyze the actual threats and errors in the cockpit regarding ATC. It is required to improve the management of ATC threats proactively. According to LOSA result, ATC threats are a frequent threat to pilots, and the most frequent type of ATC for pilots is difficult Accent or language to understand controller. These findings could be trained in the simulators and cockpit in a similar environment and workload as in actual flight for effective countermeasures.

Purpose: In this study, in order to examine the correlation between non-compliance with standard phraseology and communication errors in pilot-controller communications, investigated the perception of standard phraseology. Methods: First, the definition and regulations of the standard phraseology were confirmed through document review. The Korea’s standard phraseology for air traffic control is based on the Air Traffic Control Procedure and the Manual of Radiotelephony. The standards regulated in these documents is derived from International Civil Aviation Organization (ICAO) and/or the Federal Aviation Administration (FAA). Then, a questionnaire containing 8 test items suitable for checking compliance with the standard phraseology was prepared through expert advice. A total of 55 pilots and controllers including trainees were surveyed. Results: As a result of the survey, most of the respondents thought that the standard phraseology should be complied, but they showed poor results in the test questions about whether their phraseology were appropriate. Overall average score was 3.67 points out of perfect score of 8.00 points. Based on the respondents’ improper answers, the possibility of communication errors and linguistic background were examined through consultation with aviation experts and language experts. Conclusion: Even though they knew the need to comply with standard phraseology, they often used non-standard phraseology because they did not know the exact standard, and some communication errors were likely to occur. In order to supplement this, it is necessary to define accurate standard phraseology and make efforts at the government level as well as aviation workers and the aviation industry to train and learn properly.

Purpose: Most aviation accidents are caused by human factors, and in recent years in Korea, human factors have been identified as the cause of 70% of aviation accidents. Human factors that influence pilots in the aviation field are closely linked to judgment ability and are crucial factors directly impacting flight proficiency. Methods: To explore the human factors that may affect student pilots during flight training, a survey was conducted among flight instructors holding pilot certificates. Results: The results aim not only to identify the human factors that can influence flight performance during training but also to establish a direction for safety by addressing the human factors related to student pilots, with the goal of maintaining safety. Conclusion: Understanding the human factors that affect student pilots, who will be responsible for transporting hundreds of passengers in the future, is essential for cultivating safety knowledge and risk management skills, making it a highly important matter for accident prevention.

The fatigue of pilots is the most threatening factor in aviation safety internationally, requiring continuous management. In order to prevent aircraft accidents that may occur due to fatigue, this paper analyzes fatigue-related accident cases and previous research and suggests ways to improve the fatigue management of pilots. Problems in major fatigue accidents were active communication failure, lack of leadership of the captain, inadequate contingency management, lack of workload management, and the most important factors in accidents were inadequate decision making of continuing an approach without going around. It is necessary to proactively improve and establish go-around culture in the organization and manage human factors with training and procedures of Threat and Error Management and Crew Resource Management. In order to fundamentally prevent accidents related to fatigue fundamentally, it is necessary to establish Fatigue Risk Management and Safety Management System, and identify the actual threats and errors in the cockpit of the aircraft.

The human factors become the most important factor in aviation safety. In order to prevent accident, pilots should manage errors in the cockpit. International Civil Aviation Authority (ICAO) recommends airlines to implement line operation safety audit (LOSA) to identify the management of errors by pilots and understand real errors and the competencies. The LOSA may provide metrics of the prevalence of errors by each types and rate of trapping errors to management enhancing errors. Airlines may understand how crew respond and manage errors. The operator may enhance safety once they identify errors and train crew how they manage to reduce the most mismanagement errors. This study is to provide operators eight recommendations on how to enhance errors and LOSA understanding human errors collected through LOSA and enhancing the implementation of LOSA with guidance according to ICAO and Federal Aviation Administration. [ABSTRACT FROM AUTHOR]

Src family non-receptor tyrosine kinases are involved in signaling pathways which mediate cell growth, differentiation, transformation and tissue remodeling in various organs. In an effort to elucidate functional involvement of p60c-Src (c-Src) in spermatogenesis, the postnatal changes in c-src mRNA and c-Src protein together with kinase activity and subcellular localization were examined in mouse testes. c-src mRNA levels in testes increased during the first 2 weeks of postnatal development (PND). Following a decrease at puberty (PND 28), the c-src mRNA levels re-increased at adulthood (PND 50). Src kinase activity of testes was low at PND 7 but sharply increased prepubertally (PND 15) and highest at adulthood. Upon Western blotting, the level of c-Src protein was the highest in prepubertal testes but rather decreased in adult testes at PND 50. In adult testes, ubiquitination of c-Src proteins was apparent compared with immature one at PND 7, suggesting active turnover of c-Src by ubiquitination. In immature testes, c-Src immunoreactivity was largely found in the cytoplasm of the Sertoli cells. By contrast, in pubertal and adult testes intense immunoreactivity was localized at the adluminal and basal cytoplasm of Sertoli cells bearing elongated spermatids and early germ cells, respectively. The immunoreactivity of c-Src in the Leydig cells was increased during pubertal development, suggesting the functional involvement of c-Src in differentiated adult Leydig cells. Throughout postnatal development, some spermatogonia and spermatocytes showed intensive c-Src immunoreactivity compared with other germ cells, suggesting a possible role of c-Src in germ cell death. Taken together, it is suggested that c-Src may participate in the remodeling of the seminiferous epithelia and functional differentiation of Leydig cells during the postnatal development of mouse testes. [ABSTRACT FROM AUTHOR]

Purpose: The COVID-19 pandemic has wide spread to aviation. This study was conducted to find out the perception of flight training for student pilots in the flight training center in a university with COVID-19 pandemic. Methods: It analyzed through qualitative research by aviation subject matter experts in Korea. Results: The advantages of COVID-19 were the increased flight training opportunities due to significant decrease of aircraft operations in the airports, reduced ground school hours due to Social Distancing concerns of infection, difficulty in communication due to wearing masks, difficulty in purchasing parts for the maintenance, deterioration of skills due to reduced face to face class hours, and laxity in lifestyle were found. Conclusion: It was analyzed that the longer the corona pandemic, the lower the motivation of students due to uncertainty in the job market.

In this study, the major agronomic traits were investigated and RAPD technique was applied for the analysis of the genetic relations between the native ginsengs collected from Poonggi and Geumsan provinces in Korea. The main morphological traits were measured for a total of 54 collections of native ginseng from two areas based on UPOV standard. A total of 58 collections consisting of twenty-one native ginsengs collections from Poonggi area, twenty-nine collections from Geumsan area and four varieties of P. quinquefolium, P. japonicum, Chunpoong and Hwangsuk as controls were analyzed and clustered by RAPD. The results indicated that 01-9, 01-35 and 01-44 collections from Poonggi area were grouped into Geumsan area, while 332001, 332002 and 332003 collections from Geumsan area were grouped into Poonggi area. On comparison to the similarity of Poonggi collections (73-95%), the Geumsan collections showed 65-86% similarity in the population. Thus, the cluster should be applied according to the number of stem, number of leaves per stem and leaflet shape on the regionally native ginseng collections. The fourteen primers such as OPA02, OPA07, OPC08, OPD11, OPD20 and so on, will be used to select the native ginseng in the future studies. [ABSTRACT FROM AUTHOR]