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Effects of Composts and Soil Amendments on Physicochemical Properties of Soils in Relation to Phytophthora Root and Crown Rot of Bell Pepper

  • Kim, Ki-Deok;Nemec, Stan;Musson, George
    • The Plant Pathology Journal
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    • v.16 no.5
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    • pp.283-285
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    • 2000
  • Two field tests were conducted in 1995 to examine the effects of composts and soil amendments on physicochemical properties of soil in relation to Phytophthora root and crown rot of bell pepper. Chitosan, crab shell waste, humate, sewage sludge-yard trimmings, and wood chips were applied to test plots, some of which affected the levels of P, K, Mg, pH, and H. Physicochemical properties were not related with disease incidence, but percent organic matter, estimated nitrogen release, K, and Mg were correlated with total microbial activity. The elements K and Mg were especially responsible for the increased soil microbial activity that could affect development of root and crown rot of pepper.

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Development of dot blot hybridization method using non-radio labeled probes for the diagnosis of malignant catarrhal fever (Dot blot hybridization에 의한 malignant catarrhal fever virus의 진단법 개발)

  • Kim, Ok-Jin
    • Korean Journal of Veterinary Pathology
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    • v.7 no.1
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    • pp.1-4
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    • 2003
  • Malignant catarrhal fever (MCF) is a systemic disease of ruminants caused by a gamma herpesvirus, ovine herpesvirus 2 (OvHV-2). Dot blot hybridization (DBH) protocols for detecting and differentiating this MCF virus were developed. OvHV-2 specific primer pairs, 556/555, were used for the amplification of target DNA. Then, the amplified DNA was labeled with incorporation of digoxigenin (DIG). The Dig-labeled probe was able to detect and differentiate specifically OvHV-2 DNA. This DBH technique can be applied to confirm the presence of MCF virus on clinical samples and to differentiate specifically between OvHV-2 infection and other viral infections.

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Mural folliculitis and alopecia caused by infection with malignant catarrhal fever virus in goat (Capra hircus) (Malignant catarrhal fever virus 감염과 관련된 goat (Capra hircus)의 mural folliculitis와 alopecia)

  • Kim, Ok-Jin;Crawford, Timothy B.
    • Korean Journal of Veterinary Pathology
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    • v.7 no.1
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    • pp.5-9
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    • 2003
  • Malignant catarrhal fever (MCF) is a systemic disease of ruminants caused by a gamma herpesvirus, ovine herpesvirus 2 (OvHV-2). Four 1-year old goats (Capra hircus), which were infected with MCF virus, OvHV-2, by being housed together with MCF virus-infected seep, were referred with a I-month history of chronic dermatitis. On the other hand, MCF virus-negative goats, which were isolated for negative control, had not those kinds of skin problems. Examination of the affected goats revealed generalized alopecia, patchy erythema, and superficial erosions with histologic evidence of mural folliculitis. Fungal culture tests and external parasite tests with the scraping skin samples were negative. However, polymerase chain reaction revealed the existence of MCF virus DNAs in the lesion. These results suggested that MCF virus may induce mural folliculitis and alopecia in goat.

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REMARKS ON THE INNER POWER OF GRAPHS

  • JAFARI, S.;ASHRAFI, A.R.;FATH-TABAR, G.H.;TAVAKOLI, Mostafa
    • Journal of applied mathematics & informatics
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    • v.35 no.1_2
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    • pp.25-32
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    • 2017
  • Let G be a graph and k is a positive integer. Hammack and Livesay in [The inner power of a graph, Ars Math. Contemp., 3 (2010), no. 2, 193-199] introduced a new graph operation $G^{(k)}$, called the $k^{th}$ inner power of G. In this paper, it is proved that if G is bipartite then $G^{(2)}$ has exactly three components such that one of them is bipartite and two others are isomorphic. As a consequence the edge frustration index of $G^{(2)}$ is computed based on the same values as for the original graph G. We also compute the first and second Zagreb indices and coindices of $G^{(2)}$.

On-the-go Soil Strength Profile Sensor to Quantify Spatial and Vertical Variations in Soil Strength

  • Chung, Sun-Ok;Sudduth, Kenneth A.
    • Agricultural and Biosystems Engineering
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    • v.6 no.2
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    • pp.39-46
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    • 2005
  • Because soil compaction is a concern in crop production and environmental pollution, quantification and management of spatial and vertical variability in soil compaction for soil strength) would be a useful aspect of site -specific field management. In this paper, a soil strength profile sensor (SSPS) that could take measurements continuously while traveling across the field was developed and the performance was evaluated through laboratory and field tests. The SSPS obtained data simultaneously at 5 evenly spaced depths up to 50 em using an array of load cells, each of which was interfaced with a soil-cutting tip. Means of soil strength measurements collected in adjacent, parallel transects were not significantly different, confirming the repeatability of soil strength sensing with the SSPS. Maps created with sensor data showed spatial and vertical variability in soil strength. Depth to the restrictive layer was different for different field locations, and only 5 to 16% of the tested field areas were highly compacted.

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Ground Speed Control of a Direct Injection Sprayer

  • Koo, T.M.;Sumner, H.R.
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 1996.06c
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    • pp.500-510
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    • 1996
  • A Direct injection -mixing total -flow -control sprayer was developed and evaluated . The system provided precise application rates and minimized operator exposure to chemicals as well as providing a possibility for recycling container so f unused chemicals that can causes environmental contamination. Chemicals were metered and injected proportionally to the diluent flow rate to provide constant concentrations. The main diluent flow was varied in response to changes in travel speed. Experimental variables of the sprayer were the control interval, the sensitivity of flow regulating valve, the tolerance of control object and the sensitivity of the injection pump system. The optimal performance of the flow control system was with an average response time of 8.5 sec at an absolute steady state of error of 0.067 L/min (0.8% of flow rate). The average response time of the injection rate was -0.53 sec and the coefficient of variation (CV) of concentration was 3.2%.

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Bayesian Estimation of k-Population Weibull Distribution Under Ordered Scale Parameters (순서를 갖는 척도모수들의 사전정보 하에 k-모집단 와이블분포의 베이지안 모수추정)

  • 손영숙;김성욱
    • The Korean Journal of Applied Statistics
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    • v.16 no.2
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    • pp.273-282
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    • 2003
  • The problem of estimating the parameters of k-population Weibull distributions is discussed under the prior of ordered scale parameters. Parameters are estimated by the Gibbs sampling method. Since the conditional posterior distribution of the shape parameter in the Gibbs sampler is not log-concave, the shape parameter is generated by the adaptive rejection sampling. Finally, we applied this estimation methodology to the data discussed in Nelson (1970).

Regulation of Pathogenesis by Light in Cercospora zeae-maydis: An Updated Perspective

  • Kim, Hun;Ridenour, John B.;Dunkle, Larry D.;Bluhm, Burton H.
    • The Plant Pathology Journal
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    • v.27 no.2
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    • pp.103-109
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    • 2011
  • The fungal genus Cercospora is one of the most ubiquitous groups of plant pathogenic fungi, and gray leaf spot caused by C. zeae-maydis is one of the most widespread and damaging foliar diseases of maize in the world. While light has been implicated as a critical environmental regulator of pathogenesis in C. zeae-maydis, the relationship between light and the development of disease is not fully understood. Recent discoveries have provided new insights into how light influences pathogenesis and morphogenesis in C. zeae-maydis, particularly at the molecular level. This review is focused on integrating old and new information to provide an updated perspective of how light influences pathogenesis, and provides a working model to explain some of the underlying molecular mechanisms. Ultimately, a thorough molecular-level understanding of how light regulates pathogenesis will augment efforts to manage gray leaf spot by improving host resistance and disease management strategies.

Systemic Eosinophil Infiltration by Ovine Lungworm Infection (양 폐충 감염증에 의한 전신 호산구 침윤증)

  • Kim, Ok-Jin
    • Korean Journal of Veterinary Pathology
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    • v.6 no.1
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    • pp.7-9
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    • 2002
  • Case 1 was showed severe caughing and nasal discharge, who was one of 5-month-old 18 male sheep taking inspection for MCF experiment. Pathological examination of case 1 was conducted. Macroscopic observations were the foamy sticky fluids in nasal and tracheal cavity, the grey spots with 2-4 mm diameter on the surface of lung. Histopathological observations were severe eosinophil and other round cell infiltration in general organs including lung, trachea, small intestine, large intestine, liver. Also, in the lung, there were parasite-cutting lesions in some alveolar spaces and bronchioles. Following these observations, case 1 was diagnosed as ovine lungworm infection.

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