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Prophylactic and therapeutic studies on intestinal giant-cystic disease of the Israel carp caused by Thelophanellus kitauei II. Effects of physical and chemical factors on T. kitauei spores in vitro (향어의 장포자충(Thelohanellus kitauei)증의 예방 및 치료에 관한 기초적 연구 II. 물리화학적 요인이 장포자충 포자에 미치는 영향)

  • Lee, Jae-Gu;Kim, Jong-O;Park, Bae-Geun
    • Parasites, Hosts and Diseases
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    • v.28 no.4
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    • pp.241-252
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    • 1990
  • In a basic attempt to develop the prophylactic and therapeutic measures on intestinal giantcystic disease of the Israel carp, C), prinks carpio nudum, the effects of physical and chemical factors on viability or survival of the spores of Thelchcnellus kiteuei were checked in vitro by means of extrusion test on the polar filament. When the fresh spores suspended with 0.45% and 0.9% scdium chloride solution and distilled water were laid at $5^{\circ}C$ and $28^{\circ}C$ for short terms, the extrusion rates increased until the 3rd day, meanwhile when son;e of them were suspended with Tyrode's solution at $-70^{\circ}C$ the rates increased gradually until the 8th day. Viabilities of the spores suspended with 0.9% saline and added antibiotics to the suspension at $5^{\circ}C$ for long terms lasted for 997 days and 1, 256 days (presumed values) at maximum, respectively. The spores suspended with distilled water at $28^{\circ}C$ for long terms survived 152.4 days, but the spores suspended with Tyrode's solution at $-70^{\circ}C$ for long terms showed almost the same viable pattern as early freezing stages up to 780 days. The spores suspended with Tyrode's solution, frozen at $-70^{\circ}C$ and thawed at $5^{\circ}C$, showed the highest rate of extrusion of the polar filament. In the case of frozen spores, the extrusion rates during heating tend to become higher in accordance with the increase of frozen period, and the critical points of 180 day-frozen spores to be killed were generally 78.5 hr. at $60^{\circ}C$, 23.4 hr. at $70^{\circ}C$, 189.1 min. at $80^{\circ}C$ or 10.5 min. at $90^{\circ}C$. The longer the spores were frozen, the more time was needed for the death of spores after thawing; 20 days-17.4 days, 100 days-33.2 days, and 400 days-37.8 days. The longer the spores were frozen, the more time was needed for the death of spores at a conventional when they were dried air drying condition, 540 days-23.5 days, 160 days-21.0 days, and 20 days-14.4 days. On the other hand, the longer the spores were frozen, the more spores were dead rapidly when they were irradiated with 10W UV-ray; 100 days-26.0 hr, 300 days-21.9 hr, and 540 days-13.9 hr. The time needed for killing 200 days-frozen spores by various disinfectants at 1, 000 ppd was 5.2 min. by calcium oxide, 10.4 min. by potassium permanganate, 27.8 min. by malachite green and 14.3 hr. by formalin. Transient inhibitory effects of the extrusion of the polar filament were observed by various antiprotozoal and antifungal agents in the descending order of ketoconazole. metronidasole and dapsone. The above results presume that full drying, followed by spraying CaO and maintaining sunny condition for a few days on the concrete bottoms of knish farm may be an effective method for the prevention of intestinal giant.cystic disease.

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Immunogenicity and Safety of a Haemophilus influenzae Type b Polysaccharide-Tetanus Toxoid Conjugate Vaccine (PRP-T: HiberixTM) in Korean Infants (우리나라 영아에서 PRP-T(HiberixTM)백신의 면역원성 및 안전성에 대한 연구)

  • Chung, Eun Hee;Kim, Yae Jean;Kim, Yun Kyung;Kim, Dong Ho;Seo, Jeong Wan;Lee, Hoan Jong
    • Pediatric Infection and Vaccine
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    • v.10 no.1
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    • pp.71-80
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    • 2003
  • Purpose : Four kinds of Haemophilus influenzae type b protein conjugate vaccines, PRPD, PRP-T, PRP-OMP and PRP-CRM197, have been developed, and PRP-T vaccines are currently produced by two manufacturer, $ActHib^{(R)}$ by Aventis and $Hiberix^{TM}$ by GlaxoSmith-Kline Biologicals. The purpose of this study is to evaluate the immunogenicity and safety of $Hiberix^{TM}$ in Korean infants. Methods : Seventy-three healthy infants(43 male infants) were recruited for this study after parental informed consent was obtained. Each infant was vaccinated at 2, 4 and 6 months of age with the study vaccine. At each visit, infants were also immunized with DTaP, trivalent oral polio vaccine and hepatitis B vaccine when indicated. The serum anti-PRP antibody was measured at prevaccination, 2 month later after the 2nd dose, and 1 month later after the 3rd dose by the ELISA method. The local and systemic adverse reactions of vaccination were monitored for 3 consecutive days after each immunization. Immunogenicity of vaccine was evaluated in infants who received all the scheduled immunization and the adverse reactions were evaluated for infants who received at least one dose of the study vaccine. Results : Among seventy three infants, enrolled in this study; sixty three(37 male infants) completed all the scheduled immunizations. The geometric mean titer(GMT) of anti-PRP antibodies at prevaccination was 0.17 ${\mu}g/mL$(95% confidence interval[CI]; 0.13~0.22). The GMT of anti-PRP antibodies increased to 4.14 ${\mu}g/mL$(95% CI; 2.65~6.48) at 2 month later after the 2nd dose of PRP-T and 14.65 ${\mu}g/mL$(95% CI; 10.83~19.81) at 1 month later after the 3rd dose. Anti-PRP antibody ${\geq}0.15$ ${\mu}g/mL$, was observed in 98.4%(95% CI; 91.8~100) after 2 doses and 100%(95% CI; 100~100) after 3 doses. Anti-PRP antibody ${\geq}1.0$ ${\mu}g/mL$, was obtained in 77.8%(95% CI; 67.5~88.0) after 2 doses, and 98.4%(95% CI; 95.3~100) after 3 doses. Most of the adverse reaction after vaccination were mild. Irritability, the most common systemic reaction, was observed in 45.5%, followed by drowsiness(30.5%), poor feeding(26.7%) and fever(5.6%). Among the local reactions tenderness was observed in 7.9%, redness(${\geq}5$ mm) in 2.8% and swelling(${\geq}5$ mm) in 1.8%. Conclusion : The PRP-T vaccine used in this study was highly immunogenic and safe in Korean young infants. The finding that high GMT and high frequency of infants with a protective titer achieved after 2 doses is consistent with the previous studies which were done with a PRP-T vaccine of other manufacturer. This study suggests that the immunization schedule of PRP-T vaccine for Korean infants may need re-evaluation.

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Decision-making process and satisfaction of pregnant women for delivery method (임산부의 분만방법 결정과정과 만족도)

  • Jun, Hae-Ri;Park, Jung-Han;Park, Soon-Woo;Huh, Chang-Kyu;Hwang, Soon-Gu
    • Journal of Preventive Medicine and Public Health
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    • v.31 no.4 s.63
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    • pp.751-769
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    • 1998
  • This study was conducted to assess the attitude of pregnant women toward delivery method, understanding of the reason for determining her own delivery method, participation in decision-making process and satisfaction with delivery method after labor. Study subjects were 693 pregnant women who had visited obstetric clinic for prenatal care in the last month of pregnancy in one general hospital and one obstetrics-gynecology specialty hospital in Taegu city from February 1 to March 31 in 1998. A questionnaire was administered before and after labor and a telephone interview was done one month after labor. Proportion of women who had health education and/or counselling about delivery method during prenatal care was 24.0% and this proportion was higher for women who had previous c-section(35.5%) than others. Women thought vaginal delivery is better than c-section for both maternal and baby's health regardless of previous delivery method. About 90% of primipara and multiparous women who had previous vaginal delivery wanted vaginal delivery for the index birth, while 85.6% of multiparous women who had previous c-section wanted repeat c-section. Reasons for choosing c-section in pregnant women who preferred vaginal delivery before labor were recommendation of doctors(81.9%), recommendation of husband (0.8%), agreement between doctor and pregnant woman(4.7%), and mother's demand (12.6%). Reasons for choosing vaginal delivery were mother's demand(30.6%) and no indication for c-section(67.2%). Reasons for choosing c-section in pregnant women who preferred c-section before labor were recommendation of doctors(76.2%), mother's demand(20.0%), recommendation of husband(1.3%), and agreement between doctor and pregnant woman(2.5%). Of the pregnant women who had c-section, by doctor's recommendation, the proportion of women who had heard detailed explanation about reason for c-section by doctor was 55.1%. Mother's statement about the reason for c-section was consistent with the medical record in 75.9% . However, over 5% points disparities were shown between mother's statement and medical record in cases of the repeat c-section and mother's demand. In primipara and multiparous women who had previous vaginal delivery, the delivery method for index birth had statistically significant association with the preference of delivery method before labor(p<0.05). All of the women who had previous c-section had delivered the index baby by c-section. Among mothers who had delivered the index baby vaginally, 84.9% of them were satisfied with their delivery method immediately after labor and 85.1% at 1 month after labor. However, mothers who had c-section stated that they are satisfied with c-section in 44.6% immediately after labor and 42.0% at 1 month after labor. Preferred delivery method for the next birth had statistically significant association with delivery method for the index birth both immediately after labor and in 1 month after labor. The proportion of mothers who prefer vaginal delivery for the next birth increased with the degree of satisfaction with the vaginal delivery for the index birth but the proportion of mothers who prefer c-section for the next birth was high and they did not change significantly with the degree of satisfaction with the c-section for the index birth. These results suggest that the current high technology-based, physician-centered prenatal and partritional cares need to be reoriented to the basic preventive and promotive technology-based, and mother-fetus-centered care. It is also suggested that active involvement of pregnant woman in decision-making process for the delivery method will increase the rate of vaginal birth after c-section and decrease c-section rate and improve the degree of maternal satisfaction after delivery.

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A Case-Control Study on Effects of Genetic Polymorphisms of GSTM1, GSTT1, CYP1A1 and CYP2E1 on Risk of Lung Cancer (GSTM1과 GSTT1, 그리고 CYP1A1, CYP2E1 다형성이 폐암발생에 미치는 영향에 대한 환자-대조군연구)

  • Nan, Hong-Mei;Kang, Jong-Won;Bae, Jang-Whan;Choe, Kang-Hyeon;Lee, Ki-Hyeong;Kim, Seung-Taik;Won, Choong-Hee;Kim, Yong-Min;Kim, Heon
    • Journal of Preventive Medicine and Public Health
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    • v.32 no.2
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    • pp.123-129
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    • 1999
  • Objectives: This study was performed to investigate sweets of genetic polymorphisms of glutathione S-transferase M1 (GSTM1), glutathione S-transferase M1 (GSTT1), cytochrome P450 1A1 (CYP1A1) and cytoehrome P450 2E1 (CYP2E1) on lung cancer development. Methods: Ninety-eight lung cancer patients and 98 age-sex matched non-cancer patients hospitalized in Chungbuk National University Hospital form March 1997 to August 1998, were the subjects of this case-control study. Direct interview was done and genotypes of GSTM1, GSTT1, CYP1A1 and CYP2E1 were investigated using multiplex PCR or PCR-RFLP methods with DNA extracted from venous blood. Effects of the polymorphisms of GSTM1, GSTT1, CYP1A1 and CYP2E1, lifestyle factors including smoking, and their interactions on lung rancor were statistically analyzed. Results: GSTM1 was deleted in 67.01% of the cases and 58.16% of the controls, and the odds ratio(95% CI) was 1.46(0.82-2.62). GSTT1 deletion was 58.76% for the lung cancer patients and 50.00% for the controls[OR:1.43(0.81-2.51)]. The frequencies of lle/lle, lle/Val and Val/Val of the CYP1A1 polymorphisms were 59.18-18%, 35.71%, and 5.10% for the cases, and 52.04%, 45.92%, 2.04% for the controls, respectively. Risk of lung cancer was not associated with polymorphism of CYP1A1 ($x^2trend=0.253$, p-value>0.05). The respective frequency of c1/c1 c1/c2, c2/c2 genotypes for CYP2E1 were 50.00%, 42.86%, 7.14% for the lung cancer patients, and 66.33%, 30.61%, 3.06% for the controls $(x^2trend=5.783,\;p<0.05)$. c2 allele was a significant risk factor for lung cancer. We also observed a significant association of cigarette smoking history with lung cancer risk. The odds ratio(95% Cl) of cigarette smoking was 3.03(1.58-5.81). In multiple logistic analysis including genotypes of GSTM1, GSTT1, CYP1A1 and CYP2E1, and smoking habit, only snaking habit came out to be a significant risk factor for lung cancer. Conclusion: Genetic polymorphisms of GSTM1, GSTT1, CYP1A1 and CYP2E1 are not so strongly associated with lung cancer as lifestyle factors including cigarette smoking.

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Clinical Characteristics of Arthrogryposis, Renal Tubular Dysfunction, Cholestasis(ARC) Syndrome in Korea (ARC(Arthrogryposis, Renal Tubular Dysfunction, Cholestasis) 증후군의 발병양상에 관한 연구)

  • Lee Soon Min;Kim Ji Hong;Lee Jae Seung;Han Suk Joo
    • Childhood Kidney Diseases
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    • v.9 no.2
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    • pp.222-230
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    • 2005
  • Purpose : ARC syndrome refers to an association of arthrogryposis, renal tubular dysfunction, and cholestasis. The VPS33B gene was recently identified as the causative gene. So far, 41 cases of ARC syndrome have been reported worldwide, and it has rarely been reported in Korea. This study was conducted to report the clinical findings of seven ARC syndrome cases in Korean children, focusing especially on renal tubular dysfunction. Methods : The hospital records of 7 cases diagnosed as ARC syndrome at Severance Hospital between Mar. 1995 and Aug. 2005 were reviewed and analyzed. Results : Of the 7 cases, 4 were boys and 3 were girls. Six patients(85$\%$) were born with normal birth weight at term, and one was born at preterm. All cases presented with cholestasis and severe jaundice. According to the type of arthrogryposis described by Brown et al, type 3 and 4 were found in 2 patients and type,6, 7, and the undistributed type in one patient respectively. Other associated clinical findings were as follows : failure to thrive in 6(85$\%$), lax skin in 5(71$\%$), and gray platelet syndrome in 4(57$\%$). Urine analysis revealed 6 cases(85$\%$) with proteinuria, 3(43$\%$) with hematuria, 5(71$\%$) with glycosuria, 2(29$\%$) with phosphaturia and 2(29$\%$) with calciuria. Serum electrolytes showed 4 cases(57$\%$) with hyponatremia, 3(43$\%$) with hypokalemia, and 1(14$\%$) with creatinine elevation. Renal tubular dysfunctions were diagnosed as renal tubular acidosis in 6 cases(85$\%$), nephrogenic diabetes insipidus in 2(29$\%$), and Fanconi syndrome in 2(29$\%$). During the follow-up period, 2(29$\%$) had no treatment, 5(85$\%$) had continuous supplementation to correct the electrolyte imbalance and acidosis, and 1(14$\%$) had dialysis. Only one patient had a family history of ARE syndrome in a sibling. Four cases(57$\%$) were diagnosed at the mean age of 8.2 months, and one case was lost during follow-up. Ages of the survived 2 cases were 13 and 25 months, respectively. Conclusion : The rare disease of ARC syndrome Is associated with severe renal dysfunction. However, this study revealed that the renal manifestation of ARC syndrome in Korean children is relatively mild and survival rate is higher than that of previous studies. Contrary to previous reports, this study showed that familial cases are rare and sporadic occurence is possible in Korea. Thus, the diagnosis of this syndrome requires a careful evaluation of the venal function in cases of congenital arthrogryposis, and a mandatory genetic counseling of affected family for prevention of familial occurance. (J Korean Soc Pediatr Nephrol 2005;9:222-230)

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Analysis of Childhood Rapidly Progressive Glomerulonephritis (소아 급속 진행성 사구체신염의 임상적 고찰)

  • Uhm Ji Hyun;Kim Mi Jin;Lee Young-Mock;Kim Ji Hong;Lee Jae Seung;Kim Pyung-Kil;Hong Soon Won;Jeung Hyeun Joo
    • Childhood Kidney Diseases
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    • v.5 no.2
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    • pp.78-86
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    • 2001
  • Purpose: Rapidly progressive glomerulonephritis (RPGN) is characterized by the rapid increase in serum creatitnin and crescents formation involving more than $50\%$ of glomeruli. 10 patients who had been treated for RPGN were studied retrospectively for thier underlying diseases and clinical features Method: Cilinical review was performed on 10 children who were diagnosed with RPGN by clinical features and renal biopsy and followed up at department of pediatrics during tile last 10 years, from May 1990 to May 2000. Result: There were 6 males and 4 females between the ages of 2.1 and 14.3 years (mean $10.9{\pm}3.8$). 3 had Henoch-$Sch{\ddot{o}}nlein$ purpura nephritis; 2, idiopathic rapidly progressive glomerulonephritis; 2, lupus nephritis; 1, hemolytic uremic syndrome; 1, membranous glomerulonephritis and 1, microscopic polyangiitis. The most common chief complaints were gross hematuria and oliguria. Initial clinical features included proteinuria, edema, hypertension, nausea and arthralgia. Mean serum BUN was $74.2{\pm}39.1\;mg/dL$ mean serum creatinin, $3.2{\pm}1.8\;mg/dL$ and mean creatinin clearance, $26.5{\pm}13.2\;mL/min/1.73m^2$. Antineutrophil cytoplasmic antibody was positive only in microscopic polyangiitis. ANA and Anti-DNA antibody were positive in two lupus nephritis patients. Serum complements were decreased in 4 patients. All patients except Hemolytic uremic syndrome received steroid pulse therapy and immunosupressive agents. 3 patients were performed acute peritoneal dialysis and 2 patients were given plasmapheresis. At the last follow up, 1 patient was dead, 4 patients had elevated serum creatinin, 2 of these 4 patients were on chronic ambulatory peritoneal dialysis and 6 patients had normal renal function. Conclusion: Rapidly progressive glomerulonephritis is a medical emergency that requires very rapid diagnosis, classification, and therapy. Appropriate therapy selected on the basis of underlying disease mechanism can substantially improve renal survival. (J. Korean Soc Pediatr Nephrol 2001 ; 5 : 78-86)

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The Effects of Intravenous Methylprednisolone Pulse Therapy by Mendoza Protocol in Primary and Secondary Nephrotic Syndrome (일차성 및 이차성 신증후군에서 Mendoza Protocol에 의한 Intravenous Methylprednisolone Pulse Therapy의 효과)

  • Lee Kyoung-Jae;Han Jae-Hyuk;Lee Young-Mock;Kim Ji-Hong;Kim Pyung-Kil
    • Childhood Kidney Diseases
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    • v.5 no.2
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    • pp.117-124
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    • 2001
  • Purpose : Since Mendoza(1990)'s report that long term methylprednisolone pulse therapy by Mendoza protocol (MP therapy) is a good treatment option in focal segmental glomerulosclerosis(FSGS), there have been reports of the effects of this therapy in steroid-resistant nephrotic syndrome. However, no studies have been performed on the effects of MP therapy in steroid- dependent nephrotic syndrome and secondary nephrotic syndrome. In this study, we investigated the effects of long term MP therapy in primary and secondary nephrotic syndrome in which previous treatment options were not effective. Methods : We chose 10 children who were diagnosed with steroid-dependent minimal change nephrotic syndrome(SD-MCNS), who had shown frequent relapse during the immunocompromised or cytotoxic therapy Period, and 6 children with FSGS and 5 children with secondary nephrotic syndrome children, who had shown no response during the previous therapy period. We treated these patients according to Mendoza protocol involving infusions of high doses of methylprednisolone, often in combination with oral cyclophosphamide for 82 weeks. Results : In all the 10 children with SD-MCNS, complete remission was visible on average of $18{\pm}9$ days after MP therapy was started. However, all these children relapsed during or after MP therapy. In these children, the mean relapse rate prior to MP therapy was $2.1{\pm}1.0$ relpases/year, which was reduced to $1.4{\pm}0.9$ relapses/year during MP therapy(P>0.05) and rose to $2.7{\pm}1.0$ relapse/year after MP therapy. Of the 6 children with FSGS, 4 children($67\%$) showed complete remission, of whom 3 children($50\%$) remained in the remission status during the follow up period, $1.2{\pm}0.7$ years, after the end of MP therapy. 2 children($33\%$) showed no response. All of the 5 children with secondary nephrotic syndrome showed remission and remained in the remissiom status during the follow up period, $1.7{\pm}0.6$ years The only side effect of MP therapy was transient hypertension in 10 children of ail subjects during the intravenous infusion of methylprednisolone. Conclusion : We conclude that although long term MP therapy is not effective in the treatment of SD-MCNS, it is an effective therapy against intractable FSGS and secondary nephrotic syndrome. (J Korean Soc Pediatr Nephrol 2001 ; 5 : 117-24)

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The relationships between lead exposure indicies and urinary δ-ALA by HPLC and colorimetric method in lead exposure workers (연노출근로자에 있어서 흡광광도법과 HPLC법에 의한 요중 δ-ALA 배설량과 연노출지표들 간의 관련성)

  • Ahn, Kyu-Dong;Lee, Sung-Soo;Hwangbo, Young;Lee, Gab-Soo;Yeon, You-Yong;Kim, Yong-Bae;Lee, Byung-Kook
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.6 no.1
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    • pp.77-87
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    • 1996
  • In order to compare the difference of the measurement of delta aminolevulinic acid(${\delta}$-ALA) in urine between HPLC method(HALA) and colorimetric method(CALA), and also to provide useful information for the new diagnostic criteria of ${\delta}$-ALA in urine in lead poisoning, if at all possible in the future, authors studied 234 male lead workers who were selected from 7 storage battery factories, 3 secondary smelting industries, and 2 litharge making industries. Study subjects were selected on the basis of blood Zinc protoporphyrin(ZPP) level from low to high concentration to cover wide range of lead exposure. Study variables for this study were ${\delta}$-ALA measured by two different methods, blood lead(PbB), and blood ZPP. The results were as follows: 1. There was very high correlation between ${\delta}$-ALA measured by two method(r = 0.989 : HALA = -0.8194 + 0.8110 ${\times}$ CALA), but the value of CALA was measured about 2mg/L greater than HALA. 2. While the correlations of ${\delta}$-ALA by two method with blood lead and blood ZPP were 0.46 and 0.37 respectively, they were increased to 0.63 and 0.57 if ${\delta}$-ALA values were log-transformed. 3. Simple linear regression of ${\delta}$-ALA measured by two method on ZPP were as follows: CALA = 2.0421 + 0.0341 ${\times}$ ZPP ($R^2=0.1385$ p = 0.0001) HALA = 0.8006 + 0.0280 ${\times}$ ZPP ($R^2=0.1389$ p = 0.0001) 4. Simple linear regression of ${\delta}$-ALA measured by two method on PbB were as follows: CALA = - 0.4134 + 0.1545 ${\times}$ PbB ($R^2=0.2085$ p = 0.0001) HALA = -1.2893 + 0.1287 PbB ($R^2=0.2154$ p = 0.0001), 5. Simple linear regression of log-transformed ${\delta}$-ALA by two method on ZPP and PbB were as follows: logHALA = 0.3078 + 0.0060 ZPP ($R^2=0.3329$ p = 0.0001) logCALA = 1.0189 + 0.0044 ZPP ($R^2=0.3290$ p = 0.0001) logHALA = -0.0221 + 0.0246 PbB ($R^2=0.4046$ p = 0.0001) logCALA = 0.7662 + 0.0184 PbB ($R^2=0.4108$ p = 0.0001) 6. The cumulative percent of colorimetric method to detect lead workers whose value of PbS and ZPP were over screening level such as $40{\mu}/dl$ and $100{\mu}/dl$ respectively was higher than HPLC method if cut-off level of ${\delta}$-ALA for screening of lead poisoning was 5 mg/L. But if cut-off level of ${\delta}$-ALA measured by HPLC was reduced to 3 mg/L which is compatible to 5 mg/L of ${\delta}$-ALA measured by colorimetric method, there were good agreement between two methods and showed dose-response relationship with other lead exposure indices such as PbB and ZPP.

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A Study on the Physico-Chemical Characteristics of Acid Sulfate Soil in Kimhae Plain (김해평야(金海平野)에 분포(分布)된 특이산성토(特異酸性土)(답)(沓)의 이화학적성질(理化學的性質)에 관(關)한 조사연구(調査硏究))

  • Park, N.J.;Park, Y.S.
    • Korean Journal of Soil Science and Fertilizer
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    • v.2 no.1
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    • pp.15-26
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    • 1969
  • The study on physico-chemical characteristics of the acid sulfate soil present in Kimhae plain was carried out with 28 surface and subsoils from lower and higher produtive area and two representative profile samples from the areas reclaimed a few decades ago and around 10 years ago respectively. 1. There are no differences in soil texture between lower and higher productive soils being mostly silty clay loam and silty clay. 2. Very significant differences in pH, degree of base saturation and extractable aluminium content are observed; lower pH, lower degree of base saturation and higher aluminium in the lower productive soils and subsoils. The pH and degree of base saturation of these soils are extremely low whereas aluminium content is very high compared to ordinary paddy soil. 3. Cation exchange capacity of these soils are slightly higher than ordinary paddy soils. In higher productive soils, exchangeable calcium and magnesium are of same order, whereas in lower productive soils magnesium content is appreciably higher than calcium. 4. Though the soil is derived from marine and estuarine sediment, the soluble salt content is not high. There are only few lower productive surface soils and subsoils having Ec values of the saturation extracts higher than 4 mmhos but lower than 9 mmhos/cm. 5. Organic matter content of these soils is a bit higher compared to ordinary paddy soils, but, nitrogen content is comparatively low. C/N ratio of these soils is around 12. 6. Sulfur content is considerably higher but oxidizable sulfur is found to be very low. Total sulfur is generally high in subsoils and lower productive soils. 7. Active iron and available silica are slightly higher than ordinary paddy soils but easily reducible manganese is very low. Almost no differences are also observed between lower and higher productive soils. 8. Available phosphorus content is extremely low in particular, regardless of higher or lower productive soils. 9. The two representative profiles from the area of earlier reclamation and recent one show that samples from earlier reclaimed area contain less amount of free acids, sulfur compounds, toxic aluminium and soluble salts etc. than the other. This indicate greater leaching and possible addition of lime for a longer period of time. 10. From the results obtained, it can be concluded the higher productivity of group I soils is due to the greater leaching and neutralisation of acidity by liming materials, It can also be concluded that the productivity of both types can be increased by addition of liming materials and improvement of drainage facilities.

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A Statistical model to Predict soil Temperature by Combining the Yearly Oscillation Fourier Expansion and Meteorological Factors (연주기(年週期) Fourier 함수(函數)와 기상요소(氣象要素)에 의(依)한 지온예측(地溫豫測) 통계(統計) 모형(模型))

  • Jung, Yeong-Sang;Lee, Byun-Woo;Kim, Byung-Chang;Lee, Yang-Soo;Um, Ki-Tae
    • Korean Journal of Soil Science and Fertilizer
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    • v.23 no.2
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    • pp.87-93
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    • 1990
  • A statistical model to predict soil temperature from the ambient meteorological factors including mean, maximum and minimum air temperatures, precipitation, wind speed and snow depth combined with Fourier time series expansion was developed with the data measured at the Suwon Meteorolical Service from 1979 to 1988. The stepwise elimination technique was used for statistical analysis. For the yearly oscillation model for soil temperature with 8 terms of Fourier expansion, the mean square error was decreased with soil depth showing 2.30 for the surface temperature, and 1.34-0.42 for 5 to 500-cm soil temperatures. The $r^2$ ranged from 0.913 to 0.988. The number of lag days of air temperature by remainder analysis was 0 day for the soil surface temperature, -1 day for 5 to 30-cm soil temperature, and -2 days for 50-cm soil temperature. The number of lag days for precipitaion, snow depth and wind speed was -1 day for the 0 to 10-cm soil temperatures, and -2 to -3 days for the 30 to 50-cm soil teperatures. For the statistical soil temperature prediction model combined with the yearly oscillation terms and meteorological factors as remainder terms considering the lag days obtained above, the mean square error was 1.64 for the soil surfac temperature, and ranged 1.34-0.42 for 5 to 500cm soil temperatures. The model test with 1978 data independent to model development resulted in good agreement with $r^2$ ranged 0.976 to 0.996. The magnitudes of coeffcicients implied that the soil depth where daily meteorological variables night affect soil temperature was 30 to 50 cm. In the models, solar radiation was not included as a independent variable ; however, in a seperated analysis on relationship between the difference(${\Delta}Tmxs$) of the maximum soil temperature and the maximum air temperature and solar radiation(Rs ; $J\;m^{-2}$) under a corn canopy showed linear relationship as $${\Delta}Tmxs=0.902+1.924{\times}10^{-3}$$ Rs for leaf area index lower than 2 $${\Delta}Tmxs=0.274+8.881{\times}10^{-4}$$ Rs for leaf area index higher than 2.

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