• Korean journal of applied entomology
• /
• v.57 no.4
• /
• pp.261-269
• /
• 2018

The cowpea aphid Aphis craccivora Koch (Hemiptera: Aphididae) is a polyphagous species with a worldwide distribution. We investigated the temperature effects on development periods of nymphs, and the longevity and fecundity of apterous female of A. craccivora. The study was conducted at six constant temperatures of 10.0, 15.0, 20.0, 25, 30.0, and $32.5^{\circ}C$. A. craccivora developed successfully from nymph to adult stage at all temperatures subjected. The developmental rate of A. craccivora increased as temperature increased. The lower developmental threshold (LT) and thermal constant (K) of A. craccivora nymph stage were estimated by linear regression as $5.3^{\circ}C$ and 128.4 degree-days (DD), respectively. Lower and higher threshold temperatures (TL, TH and TH-TL, respectively) were calculated by the Sharpe_Schoolfield_Ikemoto (SSI) model as $17.0^{\circ}C$, $34.6^{\circ}C$ and $17.5^{\circ}C$. Developmental completion of nymph stages was described using a three-parameter Weibull function. Life table parameters were estimated. The intrinsic rate of increase was highest at $25^{\circ}C$, while the net reproductive rate was highest at $20^{\circ}C$. Biological characteristics of A. craccivora populations from different geographic areas were discussed.

• Korean Journal of Environment and Ecology
• /
• v.33 no.3
• /
• pp.266-279
• /
• 2019

We investigated the characteristics of fish communities and habitat status of endangered species Rhodeus pseudosericeus in Heuk Stream, a tributary of the Han River, from April to October 2018. During this period, we collected 47 species of 14 families from 10 survey stations using kick nets, cast nets, and long bag set nets. The dominant and subdominant species were Zacco platypus (37.6%) and Z. koreanus (13.8%), respectively. The next most abundant species were Squalidus gracilis majimae (11.1%), Pungtungia herzi (7.7%), Rhodeus pseudosericeus (5.0%), Microphysogobio yaluensis (4.3%), and Hemibarbus longirostris (3.0%). Among the fish collected, 19 species (40.4%) were Korean endemic species. Endangered species were R. pseudosericeus and Acheilognathus signifer while exotic species were Micropterus salmoides and Oncorhynchus mykiss, and land-locked species were Plecoglossus altivelis and Rhinogobius brunneus. The community analysis showed that the dominance and evenness indexes were mostly low and that the diversity and richness indexes were high. Moreover, the river health (index of biological integrity) was mostly excllent (1 site is good, 9 sites are very good). R. pseudosericeus inhabited widely from St. 3 to St. 9 in Heuk Stream, and its population size was large. Age groups for R. pseudosericeus estimated by the frequency distribution of total length in spawning season (April) indicated the 32~45 mm group as 1-year old, the 46~59 mm group as 2-years old, 60~69 mm group as 3-years old, and the 70~89 mm group as 4-years or older. Total length range of male and female was similar, and the sex ratio of female (426) to male (394) was 1 : 0.95. A. signifer, which had been released in Heuk Stream, inhabited from St. 4 to St. 5, but its population size was small. Lastly, this paper discusses a conservation plan for fish in Heuk Stream.

• Korean Journal of Environmental Biology
• /
• v.40 no.2
• /
• pp.148-156
• /
• 2022

Ecological occupation in irrigation ponds is a well-acknowledged fact that is essential for biodiversity conservation in agricultural ecosystems. However, there are few studies on the ecological functions and relationship between a paddy field and irrigation using macroinvertebrates in an environmentally friendly paddy field. The objective of this study is to identify the community and distribution characteristics of macroinvertebrates in an agricultural paddy field and irrigation pond ecosystems, and to provide basic data on the ecological function of an environmentally friendly paddy field. Macroinvertebrate sampling was conducted from May to September in an agricultural paddy field and irrigation pond in an environment-friendly paddy field in Boryeong city. We conducted a study to identify the distribution characteristics using macroinvertebrate species analysis, such as Functional Feeding Groups (FFGs), Habitat Oriented Groups (HOGs), rarefaction curve, and a two-way dendrogram. A total of 37 species of macroinvertebrates in 28 families, 13 orders were collected study during the period of the investigation. Dominant taxa of macroinvertebrates included Coleoptera, Hemiptera, and Odonata. In terms of FFGs, predators and gathering collectors accounted for approximately 70%, in relation to HOGs, and climbers and swimmers occupied more than 50% from both the paddy field and irrigation pond. With respect to the rarefaction curve, the irrigation pond (July) was high as E (S, 141)=18 species, while the paddy field (May) was comparatively low as E (S, 141)=9 species. In conclusion, our results revealed that macroinvertebrates, such as Notonecta triguttata, Peltodytes intermedius, Appasus major, Laccotrephes japonensis, Appasus japonicus, Sigara substriata, Enochrus simulans, and Sternolophus rufipes, were used as a habitat and spawning ground in both paddy field and irrigation pond. The irrigation pond appears to be a very important spawning ground for macroinvertebrates.

• Korean journal of applied entomology
• /
• v.46 no.1 s.145
• /
• pp.109-115
• /
• 2007

This study was carried out to determine occurrence and damage of golden apple snail, Pomacea canaliculata on water seeding area in Jeonnam province. The density of golden apple snail maintained hlgh until October 2003, but quickly decreased from November. They overwintered only in a portion of the water canals but could not find in dried paddy field. They reproduced from May and June in the canal water and paddy field, respectively. Feeding time of golden apple snail on rice seedlings was 235.2 seconds, feeding length of that was 8.4cm. When golden apple snail fed rice seedlings, the stem remain only 2.5cm from areal part which could not recover. The more density of golden apple snail, the fester feeding rate. Density and number of eggs laid of golden apple snail after overwintering was higher on bank around of paddy field than on middle of that. The percent of shell size after over wintering was higher in small (below 25mm) than big (over 36mm). But in case of Boseong area, the slze was reverse because the soil has soft mud. The survival rate of overwintering golden apple snail was lower than that of breeding. They did not move when the temperature changed rapidly, but the temperature increased they start to move. They dead almost below $-3^{\circ}C$. The damage of rice by golden apple snail in the direct water seeding was 20%. In machine transplanting, rice damaged only fore-end of leaf and recovered subsequently. When golden apple snail release in direct water seeding field, the percent of damage was 5.6% in immediately release plot. The later release, the lower damage.

• Journal of Hospice and Palliative Care
• /
• v.10 no.1
• /
• pp.35-42
• /
• 2007

Purpose: Colorectal ranter is the 4th leading cause of cancer death in Korea and the prevalence is increasing continuously. This study was aimed to figure out the problems through the clinical consideration about terminal colorectal ranter patients who had died in hospice unit. Methods: We retrospectively reviewed the medical records in 78 patients with colorectal ranter who had admitted, received palliative care, and died in a hospice unit between April 2003 and November 2006. Results: The median age of patients was 59.6 years with 45 men (58%) and 24 women (42%). The median survival in hospice and palliative care was 36 days. The median hospitalization was 22 days. The most prevalent reason for admission was pain (38 patients, 49%), and the most common symptom was also pain (70 patients, 90%). Forty eight patients (62%) took analgesics before hospice referral. Twenty seven patients (65%) of 45 patients with intestinal obstruction have been performed palliative procedures. Median survival of patients with palliative procedure was higher than that of no palliative procedure group (47 days vs 19 days, P-value=0.005). Conclusion: The duration of hospice and palliative care was not enough to care the terminal colorectal cancer. Therefore, we suggest that proper education and information should be provided to physician, patients and their family members for effective hospice and palliative care.

• Korean Journal of Ecology and Environment
• /
• v.40 no.1
• /
• pp.130-142
• /
• 2007

This study was to examine impacts of turbid water on fish community in the downstream of Yongdam Dam during the period from June to October 2006. For the research, we selected six sampling sites in the field: two sites were controls with no influences of turbid water from the dam and other remaining four sites were the stations for an assessment of potential turbid effects. We evaluated integrative health conditions throughout applications of various models such as necropsy-based fish health assessment model (FHA), Index of Biological Integrity (IBI) using fish assemblages, and Qualitative Habitat Evaluation Index (QHEI). Laboratory tests on fish exposure under 400 NTU were performed to find out impact of turbid water using scanning electron microscope (SEM). Results showed that fine solid particles were clogging in the gill in the treatments, while particles were not found in the control. This results indicate that when inorganic turbidity increases abruptedly, fish may have a mechanical abrasion or respiratory blocking. The stream health condition, based on the IBI values, ranged between 38 and 48 (average: 42), indicating a "excellent" or "good" condition after the criteria of US EPA (1993). In the mean time, physical habitat condition, based on the QHEI, ranged 97 to 187 (average 154), indicating a "suboptimal condition". These biological outcomes were compared with chemical dataset: IBI values were more correlated (r=0.526, p<0.05, n=18) with QHEI rather than chemical water quality, based on turbidity (r=0.260, p>0.05, n=18). Analysis of the FHA showed that the individual health indicated "excellent condition", while QHEI showed no habitat disturbances (especially bottom substrate and embeddeness), food-web, and spawning place. Consequently, we concluded that the ecological health in downstream of Yongdam Dam was not impacted by the turbid water.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.16 no.1
• /
• pp.12-16
• /
• 2012

Purpose : In conventional PET image reconstruction, iterative reconstruction methods such as OSEM (Ordered Subsets Expectation Maximization) have now generally replaced traditional analytic methods such as filtered back-projection. This includes improvements in components of the system model geometry, fully 3D scatter and low noise randoms estimates. SharpIR algorithm is to improve PET image contrast to noise by incorporating information about the PET detector response into the 3D iterative reconstruction algorithm. The aim of this study is evaluation of SharpIR reconstruction method in PET/CT. Materials and Methods: For the measurement of detector response for the spatial resolution, a capillary tube was filled with FDG and scanned at varying distances from the iso-center (5, 10, 15, 20 cm). To measure image quality for contrast recovery, the NEMA IEC body phantom (Data Spectrum Corporation, Hillsborough, NC) with diameters of 1, 13, 17 and 22 for simulating hot and 28 and 37 mm for simulating cold lesions. A solution of 5.4 kBq/mL of $^{18}F$-FDG in water was used as a radioactive background obtaining a lesion of background ratio of 4.0. Images were reconstructed with VUE point HD and VUE point HD using SharpIR reconstruction algorithm. For the clinical evaluation, a whole body FDG scan acquired and to demonstrate contrast recovery, ROIs were drawn on a metabolic hot spot and also on a uniform region of the liver. Images were reconstructed with function of varying iteration number (1~10). Results: The result of increases axial distance from iso-center, full width at half maximum (FWHM) is also increasing in VUE point HD reconstruction image. Even showed an increasing distances constant FWHM. VUE point HD with SharpIR than VUE point HD showed improves contrast recovery in phantom and clinical study. Conclusion: By incorporating more information about the detector system response, the SharpIR algorithm improves the accuracy of underlying model used in VUE point HD. SharpIR algorithm improve spatial resolution for a line source in air, and improves contrast recovery at equivalent noise levels in phantoms and clinical studies. Therefore, SharpIR algorithm can be applied as through a longitudinal study will be useful in clinical.

• Korean Journal of Poultry Science
• /
• v.12 no.1
• /
• pp.31-38
• /
• 1985

To learn more about the productivity of edible meat and its functional properties of spent hen, 60 White Leghorn fowls at 20 month of age were randomly divided into 6 groups, 10 hen for each group, and processed. As the productivity of edible meat, the yield of dressed carcass, giblets, cut-up meat, and breast and leg (thigh and drustick) muscles were determined. The approximate chemical composition, the content of salt-soluble protein, the emulsifying capacity and W.H.C. of breast and leg muscle were measured as the functional properties. The results were summarized as follows. 1. The average live weight of spent hen was 1,576.7g from which the yield of dressed carcass and giblets were 998.9g(63.4%) and 75.3g(4.8%) respectively. It means the yield of ready-to-cook form was 1,074.2g(68.2%) and the inedible byproducts was 502.5g (31.8%). 2. The average, weight of each part of cut-up chicken were: neck 41.0g(4.1%), wings 135.9g (13.6%), breast 276.7g (27.7%), legs 323.6g (42.4%). back 176.1g(17.6%) and the cutting-loss was 45.6g(4.6%). 3. The average weight of total edible muscle from breast and leg was 51.5g(85.86% of breast and leg cut weight) and the percentages based on the carcass and live weights were 51.6% and 32.7%, respectively. 4. The contents of H$_2$O, protein, fat and water-protein ratio of breast muscle were 72.95%, 20.54%, 1.59% and 3.55, respectively and those of leg muscle were 71.9%, 19.12%, 3.96% and 3.76%, respectively. 5. The salt-soluble protein contents of breast and leg muscle were 7.97% and 6.26% and their concentrations based on the total protein content were 38.8% and 32.74%, respectively. 6. The emulsifying capacity of breast and leg muscle was 43.23$m\ell$and 43.23$m\ell$, respectively. 7. The W. H. C- of breast and leg muscle was 54.23% and 52.61%, respectively.

• Korean Journal of Remote Sensing
• /
• v.33 no.5_1
• /
• pp.559-570
• /
• 2017

A partial least squares regression (PLSR) model was developed to map the internal soluble solids content (SSC) of apples using a ground-based hyperspectral scanner that could simultaneously acquire outdoor data and capture images of large quantities of apples. We evaluated the applicability of various preprocessing techniques to construct an optimal prediction model and calculated the optimal band through a variable importance in projection (VIP)score. From the 515 bands of hyperspectral images extracted at wavelengths of 360-1019 nm, 70 reflectance spectra of apples were extracted, and the SSC ($^{\circ}Brix$) was measured using a digital photometer. The optimal prediction model wasselected considering the root-mean-square error of cross-validation (RMSECV), root-mean-square error of prediction (RMSEP) and coefficient of determination of prediction $r_p^2$. As a result, multiplicative scatter correction (MSC)-based preprocessing methods were better than others. For example, when a combination of MSC and standard normal variate (SNV) was used, RMSECV and RMSEP were the lowest at 0.8551 and 0.8561 and $r_c^2$ and $r_p^2$ were the highest at 0.8533 and 0.6546; wavelength ranges of 360-380, 546-690, 760, 915, 931-939, 942, 953, 971, 978, 981, 988, and 992-1019 nm were most influential for SSC determination. The PLSR model with the spectral value of the corresponding region confirmed that the RMSEP decreased to 0.6841 and $r_p^2$ increased to 0.7795 as compared to the values of the entire wavelength band. In this study, we confirmed the feasibility of using a hyperspectral scanner image obtained from outdoors for the SSC measurement of apples. These results indicate that the application of field data and sensors could possibly expand in the future.

• The Korean Journal of Food And Nutrition
• /
• v.11 no.1
• /
• pp.61-67
• /
• 1998

Effects of various jelly prepared with different concentrations of agar and sugars on overall acceptability of the peach jelly were investigated. The preparations of peach for experimental jelly were carried by the mixture of peach pulp and juice(MPJ), and the extract form peach(EP). The results were summarized as follows ; 1. The pH for MPJ and EP were 3.95 to 4/31, respectively, and the brix degree were 13.0% and 11.5%, respectively. 2. The jelly prepared with MPJ added 3% agar and 30% sugar were most effective in appearance, hardness, springiness and overall acceptability. The relation of samples(P<0.001) was found to be significant. On the other hand, the jelly prepared with EP was higher scored than that with MPJ in overall acceptability, but there was no significant differences between samples. 3. The Hunter values of L*, a* and b* were the highest in both the jelly prepared with MPJ and that with EP, added 2% agar and 10% sugar. However, the L*, a* and b* values of the jelly added MPJ were higher than those of the sample added EP. 4. Texture and color scores of both the jelly added EP became higher as the concentrations of agar and sugars increased and there was significant differences between samples. 5. The relation between springiness and overall acceptability, and L* value of the jelly added MPJ showed negative at P<0.05 and that between springiness and overall acceptability of the jelly added EP also showed negative.