Honey bees are crucial pollinators for agricultural and natural ecosystems, but are experiencing heavy mortality in Korea due to a complex suite of factors. Extreme winter losses of honey bee colonies are a major threat to beekeeping but the combinations of factors underlying colony loss remain debatable. Finding solutions involves knowing the factors associated with high loss rates. To investigate whether loss rates are related to Varroa control and climate condition, we surveyed beekeepers in korea after wintering (2021–2022 to 2022–2023). The results show an average colony loss rate of 46%(2022) and 17%(2023), but over 40% colony loss before wintering at 2022. Beekeepers attempt to manage their honey bee colonies in ways that optimize colony health. Disentangling the impact of management from other variables affecting colony health is complicated by the diversity of practices used and difficulties handling typically complex and incomplete observational datasets. We propose a method to 1) Varroa mite population Control by several methods , and 2) Many nursing bee put in hive before wintering.

South Korea has over 0.38 million of managed honey bee (Apis cerana) colonies before 2009 years ago, which produce the highest quantity of honey in the Korea; however, almost colony (90%) were collapsed by Korean Sacbrood Virus (KSBV) in South Korea. Korean Sacbrood Virus (KSBV) is the pathogen of A. cerana Sacbrood disease, which poses a serious threat to honeybee A. cerana, and tends to cause bee colony and even the whole apiary collapse. Colony collapse of A. cerana was first reported on the Pyeong-Chang of the South Korea in 2009. Several scientists and governments has been tried research for cure the sacbrood disease in A. cerana colony by medicines and management techniques. Unfortunately, The sacbrood disease dosen’t improve. So, we were developed a better breed of A. cerana for resistance of sacbrood virus by selection and then artificial insemination. A. cerana breeding technique was first successful applied with A. cerana in Korean. Queens was grafted from sacbrood resistance line and then it was growing in sacbrood disease colony that was survived 100%. Altogether selected 18 queens were artificially inseminated and 2,000 drones of A. cerana in Korea was used to evaluate amount of semen collection. We are select two scabrood resistance A. cerana line (R and H). R line be used for rearing the Queen. Drone was reared in H line colony. The RH hybrid were not infected sacbrood virus even spread sacbrood virus (2×106). RH colonies have very excellent hygienic behavior, brood, and sacbrood disease resistance activity.

Ochratoxin A, which is frequently detected in cereals and infant diets worldwidely, is a mycotoxin to damage mainly the kidney and liver. Because ochratoxin A is highly thermostable compound. it is necessary to study ways of reducing level of ochratoxin A by controling processing steps. However, food processes, including extrusion, expansion, roasting, and steam cooking, which are used in order to mitigate the contents of ochratoxin A, are known to produce polycyclic aromatic hydrocarbons, which are generated from radicals decomposed by pyrolysis. Therefore, this study analyzed the levels of 4 polycyclic aromatic hydrocarbons, benz (a) anthracene, chrysene, benzo (b) fluoranthene and benzo (a) pyrene in rice-based products made in high pressure and heating process. Rice samples were finely ground, and homogenized samples were alkaline treatement with 1 M KOH/EtOH and extracted with liquid-liquid extraction method using n-hexane. The extracted solution was pretreated with a silica cartridge. The purified solution was dried with nitrogen gas and dissolved in 1 mL of dichloromethane and injected into GC/MSD. We had overall recoveries for 4 polycyclic aromatic hydrocarbons spiked into rice samples ranging from 92.8 to 110.2%. The limit of quantitations of benz (a) anthracene, chrysene, benzo (b) fluoranthene and benzo (a) pyrene in rice-based product were 0.19 ng/g, 0.38 ng/g, 0.51 ng/g, and 0.31 ng/g, respectively. However, these 4 polycyclic aromatic hydrocarbons in all processed rice samples were not detected.

The cabbage whitefly Aleyrodes proletella L. (Hemiptera: Aleyrodidae) is a specialized insect that uses its mouthparts(stylets) to feed from the phloem of its host plants, which are found among the Brassicaceae and Asteraceae. Female whiteflies lay their eggs in circular patterns embedded in wax on the underside of the leaves. These were collected from the leaf of triangular lettuce, Crepidiastrum sonchifolium throughout the whole Chungnam province, 2013. We reared the cabbage whitefly on the egg-plant. The elongate-oval eggs are laid upright in a semicircle on the underside of Brassica leaves but didn’t in lab. Initially pale and translucent, the eggs become darker. Nymphs are scale-like and covered with wax; their color is white with two yellow spots on the abdomen. On the dorsal surface of the last abdomial segment is the vasiform orifice charactersitic of the group. The fourth instar is called the “pupa”. The pupa is thicker, immobile, and pale in color with red eyes. The adults are tiny, about 1.5 mm long, and moth-like. The head and thorax are dark. The abdomen is yellow and covered by a conspicuous white waxy layer. The forewings have a faint, dark bar. If disturbed, the adults fly readily. The duration of development of immature stages of Aleyrodes proletella decreased with increase in temperature, the mortality was higher below 16 ℃ and above 28 ℃.

Several Mites are currently the most serious threat to the world bee industry. The ectoparasitic honey bee mites was originally confined to the Asian honey bee(Apis cerana etc.). Varroa destructor and Tropilaelaps clareae has plagued European honey bees, Apis mellifera. Differences in mite tolerance are reported between two honey bee species A. mellifera and A. cerana. We were amplified antimicrobial peptide cDNA genes (Defencin, Abaecin, Royalisin, Apidaecin and Hymenoptaecin) by RT-PCR. We explored the transcriptional response to mite parasitism in A. mellifera 4th instars larvae which differ in susceptibility to V. destructor and T. clareae, comparing parasitized and non-parasitized 4th instars larvae (worker and Drone) from same hive. Differential gene expression of worker bees and Drone bees induced by mites (V. destructor and T. clareae) infection was investigated by northern blot. Mites (V. destructor and T. clareae) parasitism caused changes in the expression of genes related to sex distinction. Bees tolerant to mites (V. destructor and T. clareae) were mainly characterized by differences in the expression of genes regulating antimicrobial gene expression. It provides a first step toward better understanding molecular expression involved in this differential sex distinction host-parasite relationship. We were detected bee virus in A. mellifera, comparing parasitized and non-parasitized 4th instars larvae (worker and Drone). Therefore, this result was demonstrated that mites were another possible route of horizontal transmission, as several viruses were detected in mites and their hosts.

South Korea has over 38 millions of managed honey bee (Apis cerana) colonies before 2009 years ago, which produce the highest quantity of honey in the Korea; however, almost colony (99%) were collapsed by Korean Sacbrood Virus (KSBV) in South Korea. Korean Sacbrood Virus (KSBV) is the pathogen of A. cerana Sacbrood disease, which poses a serious threat to honeybee A. cerana, and tends to cause bee colony and even the whole apiary collapse. Colony collapse of A. cerana was first reported on the Pyeong-Chang of the South Korea in 2009. Symptoms of KSBV include the rapid transmission of larval stage honeybees (A. cerana), many dead larvae found in the bottom of hive and comb. Honeybees (A. cerana) are a very important species because they provide a number of pollination services for various ecosystems in some provinces (ex. jeon-nam, jeon-buk province). They are also extremely important organisms within human society, both agriculturally and economically. The fact that a direct cause has been determined suggests that colony collapse is a complex problem with a combination of natural and anthropogenic factors. Possible instigators of colony collapse include: wax moth, viral and fungal diseases, increased population, decreased genetic diversity, climate changing and a variety of other factors. The interaction among these potential causes may be resulting in immunity loss for honeybees and the increased likelihood of collapse.

Most traditional genome sequencing projects involving infectious viruses include culturing and purification of the virus. This can present difficulties as an analysis of multiple populations from multiple locations may be required to acquire sufficient amount of high-quality DNA for sequence analysis. The electrophoretic method provides a strategy whereby the genomic DNA sequences of the Korean isolate of Pieris rapae granulovirus (PiraGV-K) were analyzed by purifying it from host DNA by pulsed-field gel electrophoresis, thus simplifying sampling and labor time. The genomic DNA of infected P. rapae was embedded in agarose plugs, digested with a restriction nuclease and methylase, and pulsed-field gel electrophoresis (PFGE) was used to separate PiraGV-K DNA from the DNA of P. rapae, followed by mapping of fosmid clones of the separated viral DNA. The double-stranded circular genome of PiraGV-K encodes 120 open reading frames (ORFs), covering 92% of the sequenced genome. BLAST and ORF arrangement showed the presence of 78 homologs to other genes in the database. The mean overall amino acid identity of PiraGV-K ORFs was highest with the Chinese isolate of PiraGV (~99%), followed up with Choristoneura occidentalis ORFs at 58%. PiraGV-K ORFs were grouped, according to function, into 10 genes involved in transcription, 11 involved in replication, 25 structural protein genes, and 15 auxiliary genes. Genes for Chitinase (ORF 10) and cathepsin (ORF11), involved in the liquefaction of the host, were found in the genome. The recovery of PiraGV-K DNA genome by pulse-field electrophoretic separation from host genomic DNA had several advantages, compared with its isolation from particles harvested as virions or inclusions from the P. rapae host. We have sequenced and analyzed the 108,658 bp PiraGV-K genome purified by the pulsed field electrophoretic method. The method appears to be applicable to the analysis of genomes of large viruses. The chitinase, identified by PiraGV-K genome sequence, was functionally characterized by quantitative PCR, Western blot analysis, immunohistochemistry and transmission electron microscopy.

The traditional use of insects as food continues to be widespread in tropical and subtropical countries and to provide significant nutritional, economic and ecological benefits for rural communities. Specially, Bee brood serves as a food source to humans in many countries although limited data exists concerning its nutrient composition. Bee brood (pupa and larvae) were analyzed for Carbohydrate, Saturated fatty acid, Cholesterol, protein, fat, fiber, minerals, and vitamins. Bee brood was high in protein(46.4%～46.73%), fat(18.84%～ 20.75%),carbohydrate(24.66 %～35.79 %), Folic acid(222.30 ㎍/100g), and vitamins. Differentially, folic acid had been contained by high density in pupa of drone. While low in iron, bee brood was a good source of folic acid, and carbohydrate. The fat was composed mostly of saturated and mono-unsaturated fatty acids. The present data suggest bee brood to be an excellent source of many valuable nutrients including energy, amino acids, many essential minerals, and B-vitamins. These data suggest bee brood could be a valuable source of nutrients to various populations.

The current status of insect pollinator use was surveyed. Honeybee was larger than mason bee and bumblebee in average use area per farm household at kinds of insect pollinator. Insect pollinator was used at 19 crops. Among them, tomato was the most used crop, which was 44.9%, and in order to apple 26.7%, strawberry 13.1%, red-pepper 7.7% and watermelon 3.7%. In the use of insect pollinators, bumblebee, which was 56.9%, was higher than honeybee (31.3%) and mason bee (11.8%). The most farmers were a positive intention except for 1.5% of farmer in the use of insect pollinator for crop pollination. The best advantage in insect pollinator use was improvement of seed setting percentage, which was 28.3% and the worst problem was low activity at bad weather, which was 25.8%. And also, 97% of farmers have an intention to use continuously insect pollinator.

Sacbrood virus(SBV) causes a fatal disease(sacbrood) of honeybee larvae, which fail to pupate, change color and shape, and finally die. The complete nucleotide sequence of SBV has recently been determined, and with these data, we now report a Reverse Transcription-PCR(RT-PCR) test for the direct, rapid, and sensitive detection of these viruses. To detect the SBV infection in Korea, we collect beekeepers from various apiaries, which the RT-PCR technique was used. And we designed SBV specific primers in conserved region of the viral genome in the GenBank database. We confirmed the SBV amplicon using cloning and sequence. Homology between determined sequences of SBV korean strain and published virus sequences were 97% in DNA sequence, and 100% in amino acid sequence. We describe the first time that presence of sacbrood virus(SBV) in Korea honey bee colonies using RT-PCR. We also developed and validated a RT-PCR assay for the detection of SBV in Korea.

Viruses of the honeybee, Apis mellifera L. are known to reside at low levels in colonies, typically showing no apparent signs of infection. Chronic paralysis virus(CBPV) is known to induce significant losses in honey bee colonies. The pathology is characterized by clusters of trembling, flightless, crawling bees and by individual bees, sometimes hairless, standing at the hive entrance. A minusstrand-specific RT-PCR was used to assess viral replication. This is the first report on the infection of CBPV in Korea. Using (-)RT-PCR, 27 apiaries in korea were screened for the honeybee viruses, with positive colonies being analysed for viral genetic diversity. We got 550-nt PCR product from CBPV genomic RNA. Nucleotide sequences were aligned to the complete CBPV genomic RNA sequence deposited in the GenBank database and was revealed 96%(AM-CBPV) identity, respectively. Sequence comparison with other CBPV and honeybee virus.

Mortality of honeybees is a serious problem that beekeepers have to face periodically in Korea and worldwide. The presence of RNA viruses, in addition to other pathogens may be one of its possible causes. In this work, we detected Deformed wing virus(DWV), Israle Acute Paralysis Virus (IAPV), Black queen cell virus (BQCV), Cloudy wing virus(CWV), Kashmir bee virus(KBV), Sacbrood virus(SBV), Chronic bee paralysis virus(CBPV) in samples of korea honeybees with or without Varroa destructor and Nosema apis. The detection of viruses in all provinces, simultaneous co-infection of colonies by several viruses and the fact that 96.3% of the samples were infected with one or more virus, indicates they are widely spread in the region. Using uniplex and multiplex RT-PCR we screened honey bee colonies for the presence of several bee viruses, including DWV, IAPV, BQCV, KBV, CWV, and described the detection of mixed virus infections in bees from these colonies. Conclusively, investigated disease of the bee, and confirmed new virus that lead to bee disease, this is thought by valuable thing as data for development of beekeeping industry such as CCD(Colony Collapse Disorder)'s cause searching examination.

The main objective of this paper is to analyze the r('ctangular stiffened plates with two opposite ends elasti cally restrained and t he others simply supported subjected to in-plane bending by Finite Element κ1ethod. Another objecti ve is to develope Classical Method analyzing the unstiffened rectangular plates with the above boundary conditions. In order to validate finite element and classical methods, the buck , ling strengths of the rectangular plates with four simply supported ends, and with two simply supported and the others fixed ends by fini te element method and classical method are compared with those of references. In finite element method, elas tically restrained ends can be obtained as considering torsional and warping rigidities of end stiffeners. The buckling strengths of the rectangular plates with elastically restrained ends by finit e element and classical methods are calcu lated and compared with each other.In case of stiffened plates, to validate finite elernent rnethod, the buckling strengths of the rectangular stiffened plates with four sirnply supported ends, and with two sirnply supported and the others fixed ends are also cornpared with those of references. The buckling strengths of the rectangular stiffened plates with elastically restrained ends by finite elernent rnethod are calculated as solving eigenvalue problerns which are obtained as assernbling rectangular plate elernents and bearn elernents considered torsional and warping rigidities. The buckling strengths of rectangular stiffened plates according to various positions of rectangular intermediate stiffener, J and 1" of end stiffeners are also obtained, which are cornpared to deterrnine the efficient position of interrnediate stiffener.

열간압연된 형강은 수직재나 휨재 등으로 사용할 때 파이프나 덕트 등의 설비에 필요한 공간을 확보하기 위해 웨브에 개구부를 두기도 한다. 개구부를 갖는 형강의 웨브는 면내력을 받는 사각형 평판으로 고려하여 좌굴하중을 구하였다. 재하변은 단순지지로 하고 재하변은 직각인 변은 탄성지지단으로 보고 해석하였으며, 국부좌굴에 대한 보강을 위해 개구부 주위(하중 방향과 평행한 두변)에 보강재를 두어 단면 손실에 대한 좌굴하중의 감소를 보강하였다. 본 연구에서는 평판에 대한 고전적인 이론해와 유한요소에 의한 해석해를 비교하여, 해석에 대한 해의 정확성을 검증한 후 개구부의 크기, 보강재의 크기와 탄성지지단의 비틀림 상수의 변화에 대한 효과를 알아보았다. 그 결과 이론해와 해석해의 오차는 0.31%로 상당히 정밀한 해석해를 얻었으며, 비틀림 상수의 크기와 보강재의 크기에 따라 유공 보강판의 효과적인 개구부 크기를 결정하였다.

Acinetobacter baumannii is usually considered an opportunistic pathogen that it responsible for a variety of nosocomial infections, such as, pneumonia, tracheobronchitis, meningitis, endocarditis, peritonitis, skin and soft tissue infections, and urinary tract infections. However, over the years, the organism has developed substantial antimicrobial resistance, and thus, the management of infections has become more difficult. The less common infective endocarditis is one of the more serious consequences of nosocomial bacteremia. Here, we report the successful treatment of the first case of multidrug-resistant A. baumannii endocarditis in a 33-year-old patient.