• The Korean Journal of Mycology
• /
• v.51 no.4
• /
• pp.429-440
• /
• 2023

Wild Lentinula edodes (shiitake) strains are an important breeding material for developing new varieties suitable for various consumer preferences and environmental conditions. The morphological characteristics of 100 wild shiitake strains collected from 14 regions were investigated in a sawdust block cultivation. The characteristics of their fruiting bodies were diverse. Among them, 38% of the caps was convex, 33% was broadly umbonate, 27% was applanate, and 2% was shallowly depressed. In terms of their stipes, 55, 23, and 22% were the column, clavate, and funnel type, respectively. The shape of the cap was the most diverse on Mt. Hwaak, whereas the shape of the stipe showed various phenotypes from various regions. Even among strains collected from the same forest, different types of mushrooms were observed. In conclusion, wild shiitake strains that have adapted to various environmental stress can be used to develop new varieties. Thus, securing various genetic resources and studying their traits are important for researching breeding technology.

• Information Systems Review
• /
• v.20 no.4
• /
• pp.59-78
• /
• 2018

With the advent of the various device types and marketing communication, customer's search and purchase behavior have become more complex and segmented. However, extant research on multichannel marketing effects of the purchase funnel has not reflected the specific features of device User Interface (UI) and User Experience (UX). In this study, we analyzed the marketing channel effects of multi-device shoppers using a unique click stream dataset from global online retailers. We examined device types that activate online shopping and compared the differences between marketing channels that promote visits. In addition, we estimated the direct and indirect effects on visits and purchase revenue through customer's accumulated experience and channel conversions. The findings indicate that the same customer selects a different marketing channel according to the device selection. These results can help retailers gain a better understanding of customers' decision-making process in multi-marketing channel environment and devise the optimal strategy taking into account various device types. Our empirical analyses yield business implications based on the significant results from global big data analytics and contribute academically meaningful theoretical framework using an economic model. We also provide strategic insights attributed to the practical value of an online marketing manager.

• Applied Biological Chemistry
• /
• v.15 no.1
• /
• pp.49-57
• /
• 1972

Varietal difference in root distribution and other root characteristics were investigated under fold and water culture condition. The results were as follows: 1. IR667 showed funnel type of root distribution in soil profit while Jinheung had barrel type, and each type appearance was more distinguishable with fertilizer application. 2. Root weight per tiller was smaller in IR667 than in Jinheung and IR667 had more root in 0 to 5cm of soil depth but Jinheung had more in 5 to l0cm depth. 3. Horizontal distribution of root was dencer near to stem base without fertilizer than with fertilizer in both IR667 and Jinheung indicating structural construction for intensive nutrient uptake. Between varieties this 'dence to stem base' trend accompaning 'dence to wide spacing side' was greater in IR667 without fertilizer and these were quite true with fertilizer in Jinheung. 4. The decreasing rates of root and ear weight by fertilizer application were greater in IR667 than in Jinheung. This and other characteristics indicated that the root of IR667 is likely to be panicle-number type comparing with Jinheung. 5. The root of IR667 had lower oxidizing power of ${\alpha}-naphthylamine$ than that of Jinheung indicating weaker resistance to reductive soil but cation exchange capacity of water-cultured root was higher in IR667 suggesting stronger nutrient uptake. 6. The content of phosphorus and especially potassium in root were higher with fertilizer but lower without fertilizer in IR667 than in Jinheung indicating that IR667 is more sensitive to root environment. 7. The contents of N, K and CEC were increasing toward root tip while P content was decreasing. The root from surface soil had higher N and K content than that from subsoil. The contents of N,P,K, and CEC of root at harvesting stage were about 1.0%, 0.1%, 0.5% and 15me/100g at dry weight base, respectively.

• Journal of Periodontal and Implant Science
• /
• v.23 no.1
• /
• pp.77-96
• /
• 1993

This in vitro study was undertaken to observe whether citric acid application aids the attachment and proliferation of human periodontal ligament cells to the root surfaces of periodontally diseased teeth. The roots were prepared so that the comparison could be made among the control healthy root surface, citric acid demineralized and non-demineralized root planted surfaces. Prior to the cell attachment experiment, each groups were prepared for scanning electron microscopic (SEM) examinations of root surface morphology, All specimens were fixed with phosphate buffered glutaraldehydes, postfixed with phosphate buffered osmium tetraoxide and stained with phosphate buffered tannic acid. dehydrated in ethanol, critical point dried, sputter coated with gold and examined under the SEM. In the cell attachement experiment, human cultured periodontal ligament cells at concentration to $4.5{\times}\;10^4\;cells/ml$ were seeded in each culture well which contained prepared roots and incubated for 30min 1, 2, 6, 12 and 24 hours at 37, 5% $CO_2$air incubator. Than the specimens were prepared for SEM examination using, the same methods as described above. In the cell proliferation experiment, $5{\times}\;10^4\;cells/ml$ cells were seeded incubated with the specimens for 6 hours. Then, all of the specimens were moved into fresh culture well and incubated for 24, 48, and 72 hours. The cell counting was done after trypsinization, under light microscope. The results were as follows. When viewed the surface morphology prior to the cell attachment, the non acid treated root planed surface displayed scaling striation and occasional bacteria and calculus. The citric acid treated specimens displayed little debris on the surface and funnel shaped orifices of dentinal tubules. There were no apparent differences in the morphology of cells attached to the control and experiment groups. However, in initial attachement, there was a slight more enhanced appearance in attachment in citric acid treated groups than other root surfaces. After 6 hours of incubation, most of the cells initiated the alteration of cell morphology from ovoid to spindle shapes. After 24 hours of incubation, most of the cells displayed proliferated appearance and connected with each other via numerous processes. In the cell proliferation experiments, there were statistically significant increased number of cells in citic acid treated groups than other groups.

• Journal of Korean Society of Forest Science
• /
• v.106 no.4
• /
• pp.509-517
• /
• 2017

This study was conducted to assess effect of thiacloprid fogging on non-target insect communities in Korean white pine forests. In addition, we assessed effect of thiacloprid fogging on mortality of Monochamus saltuarius as a vector of pine wood nematodes, and Apis mellifera as a non-target species. We compared abundance, species richness, and compostion of insects, and mortality of two insects among four treatment groups (control and thiacloprid-fogged groups with 3 different doses) located in the Kangwon National University Forest. For sampling of insects, 6 pitfall and 2 multi-funnel traps and 3 waterproof cloth sheets were placed in each study plot. In addition, M. saltuarius and A. mellifera were put into each meshed cage which installed at 7 m and 15 m heights in center of each study plot. Thiacloprid was fogged only once (middle May) in each plot using a fogging machine. Overall, thiacloprid fogging was appeared to be low toxicity to the abundance, species richness, and compostion of insects and mortality of A. mellifera, while it seems effectively impact on the mortality of M. saltuarius. However, thiacloprid fogging seems more influenced by microclimates in forests because the mortality of M. saltuarius in mesh cages was different according to heights and spatial locations. To control the population density and dispersal of M. saltuarius using by fogging techniques, therefore, it may be necessary to minimize the uncertainty about the effectiveness of thiacloprid fogging by improving the fogging techniques.

• Journal of Mushroom
• /
• v.10 no.3
• /
• pp.109-114
• /
• 2012

To develop new variety of oyster mushroom, 63 intra-specific hybrids between the strain Suhan and #Nongi201 were developed using hyphal anastomosis technique in 2004. The Po2008-275 hybrid between the dikaryon strain 04-154(Suhan x #Nongi201) and the monokaryon strain derived from ASI2487 were developed using hyphal anastomosis in 2008. The Po2008-275 was shown the best cultural characteristics, selected to be a new variety and named as 'Guseol'. The new commercial strain, 'Guseol' had dark grey pilei and grows well under spring and autumn conditions in Korea. The fruiting bodies of 'Guseol' were of an excellent quality in that not only the stipe was thick and long but also the pileus was small and hard. The optimum temperatures for mycelial growth and fruiting body development were $25{\sim}30^{\circ}C$ and $10{\sim}16^{\circ}C$, respectively. Time period required for the initiation of the first fruiting body was about 3 to 5 days depending on the temperatures. The shape of fruiting body was thin funnel shape. Fruiting body production per box($43{\times}43{\times}12cm$) was about $1545{\pm}400.9g$ which was almost 137% quantity compared to that of parental strain 04-154. Relatively low temperature incubation ($11^{\circ}C$) resulted in the development of better quality of 'Guseol' mushrooms. When two different media including potato dextrose medium and mushroom complete medium were compared, the mycelial growth of this mushroom were much faster in mushroom complete medium. Similar results were observed with other variety '#Chunchu2'. Analysis of the genetic characteristics of the new commercial strain 'Guseol' showed a major DNA profile as that of the parental 04-154 when primer URP 1, primer URP 2 and primer URP 5 were used, but different to '#Chunchu2' that was used as a control. This new variety of the dark grey oyster mushroom had smart and high quality image that corresponds well to "health food". We therefore expect that this new strain will satisfy the consumers demand for variety and excellent mushrooms.

• Pediatric Infection and Vaccine
• /
• v.23 no.2
• /
• pp.109-116
• /
• 2016

Purpose: Recent observational studies have found that vitamin D deficiency is associated with respiratory tract infections. However, randomized controlled trials (RCTs) regarding the efficacy of vitamin D in childhood respiratory tract infection (RTI) have yield inconsistent results. We performed a systematic review and meta-analysis to evaluate the association between vitamin D supplementation and the risk of RTI. Methods: A comprehensive search was conducted using MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trial. Randomized controlled trials of vitamin D supplementation for prevention of RTI in children were included for the analysis. Cochrane Collaboration's tool for assessing the risk of bias was used to assess the quality of the studies. Pooled risk ratios with 95% confidence intervals (CIs) were meta-analyzed using Review Manager 5.3. Results: A total of seven RCTs were included in the meta-analysis. According to a random-effects model, the risk ratio for vitamin D supplementation was 0.82 (95% CI: 0.69-0.98) and $I^2=62%$ for heterogeneity. On subgroup analysis, heterogeneity decreased in the subgroup with follow-up less than 1 year, participants ${\geq}5years$ of age, patients subgroup, and subgroup with dosing daily. Funnel plot showed that there might be publication bias in the field. Conclusions: The present meta-analysis supports a beneficial effect of vitamin D supplementation for the prevention of RTI in children. However, the result should be interpreted with caution due to limitations including a small number of available RCTs, heterogeneity among the studies, and potential publication bias.

• Journal of Chest Surgery
• /
• v.36 no.3
• /
• pp.164-174
• /
• 2003

Background: The Nuss procedure is a recently developed technique for minimally invasive repair of pectus excavatum using a metal bar. Although its technical simplicity and cosmetic advantages are remarkable, applications have been limited to children with standard pectus excavatum. We report a single center experience of the technique that has been evolving in order to correct asymmetric pectus configurations and adult patients. Material and Method: Between August 1999 and June 2002, 322 consecutive patients un-derwent repair by the Nuss technique and its modifications. Among them, 71 (22%) were adults. For the precise correction, morphology of the pectus was classified as symmetric and asymmetric types. Asymmetric type was subdivided into eccentric and unbalanced types. In repair, differently shaped bars were applied to individual types of pectus to achieve symmetric correction. Result: Symmetric type was 57.5% (185/322) and asymmetric type was 42.5% (137/322). Eccentric, unbalanced, and combined types were 71, 47 and 19, respectively, Major modifications were bar shaping and fixation. In asymmetric group, different shapes of asymmetric bars were applied (n=125, 38.8%). For adult patients, double bar or compound bar technique was used (n=51, 15.8%). To prevent bar rotation, multipoint wire fixations to ribs were used. Major postoperative complications were pneumothorax (n=24, 7.5%) and bar displacement (n=11, 3.4%). 42 patients had bar removal 2 years after the initial procedure. Conclusion: The Nuss procedure is safe and effective. Modifications of the techniques in accordance with precise morphological classification enabled the correction of all variety of pectus excavatum including asymmetric types and adult patients.

• Journal of Chest Surgery
• /
• v.35 no.12
• /
• pp.882-889
• /
• 2002

Acute Complications of Remodelling Plasty of Costochondral Rib Cage For Pectus excavatum Recently, Remodelling Plasty of Costochondral Rib Cage has been introduced as an minimally invasive procedure and expanded its application for pectus excavatum. Outcomes and acute complications were reviewed Material and Method: A retrospective survey of 55 patients who underwent Remodelling Plasty of Costochondral Rib Cage from September, 1999 to February, 2002 was conducted to review complications, postoperative treatments, and outcomes. Result: Age ranged from 1 to 27 years(mean 11.4 $\pm$ 7.1). 35(64%) were less than 15-year old and 20(36%) were more than 15-year old. There were 44(80%) Male patients and 11(20%) female patients. Length of hospital stay was 7.8 $\pm$ 2.1 days for less than 15-Y-old group, 10.6 $\pm$ 6.2 days for more than 15-Y-old group(p ＝ 0.042) One substernal bar was inserted in 52 patients and two substernal bars were inserted in 3 patients. As for stabilizer, one lateral side was fastened in 15 patients and both lateral sides were fastened in 6 patients. In the less than 15-Y-old group, 4 patients needed stabilizer, whereas in the more than 15-Y-old group, 18 patients needed stebilizer(s)(p ＝ 0.000). Including all kinds of complications, 28(51 %)patients had postoperative complications. Of them, only 7 patients were treated for complications(C-tube insertion was done in 7 patients and reoperation for bar refixation or removal was done in 3 patients of them). Conclusion: Most complications after Remodelling Plasty of Costochondral Rib Cage For Pectus Excavatum were trivial without treatment although C-tube drainage was needed in some patients. However bar displacement such as rotation and lateral sliding should be corrected as soon as detected in order not to remove the bar(the worst situation).

• Journal of Chest Surgery
• /
• v.37 no.6
• /
• pp.524-529
• /
• 2004

Background: Since the Nuss procedure for the correction of pectus excavatum is in its early stage, there have been problems that need to be solved. We examined complications in a single-institute experience of the Nuss technique in order to develop possible solutions to prevent them. Material and Method: 335 consecutive patients, who underwent the modified Nuss procedure between August 1999 and October 2002, were studied retrospectively. Median age was 8 years (range 1 to 46). 264 patients (78.8%) were in pediatric group (age$\leq$15) and 71 patients (21.2%) were in adult group (age> 15). 193 patients (57.6%) had symmetric and 142 patients (42.4%) had asymmetric pectus configurations. Risk factors predicting postoperative complications were analyzed using multi-variate logistic regression. Result: Postoperative complication rates were 18.9% (61/335) in total patients. Frequent complications were pneumothorax 24 (7.5%), bar displacement 11 (3.4%), and wound seroma 10 (3.1%) in order. Early complications (within a month, 49 cases, 15.2%) were pneumothorax (n=23, 6.9%), wound seroma (n=12, 3.6%), and bar displacement (n=8, 2.4%). Late complications (after a month, 12 cases, 3.7%) were pericarditis and pericardial effusion (n=5, 1.5%), bar displacement (n=4, 1.2%), and hemothorax (n=3, 0.9%). Techniques were modified to prevent complications especially in bar shaping and fixation, which led to decrease complication rate in later experience (Operation Date 1: 15/51 (29.4%) vs Operation Date 2: 34/284 (12.0%), p=0.004). Grand Canyon type (eccentric long canal type) showed higher complication rate than other types (GC type: 12/30(40%) vs Others: 37/305 (12.1%), p<0.001). Major risk factors are severity of pectus (OR=2.88, p=0.038), Grand Canyon type (OR=2.82, p=0.044), and Op. Date 1 (OR=4.05, p=0.001). Conclusion: Major complications were related to severe eccentric type of pectus configuration (Grand Canyon type) and lack of surgeon's experience (Op. Date 1). Com-plication rate was reduced with accumulation of experience and advancement of surgical techniques. The Nuss procedure can be performed at a low risk of complications with our current technique.