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      • SCOPUSKCI등재

        Vegetation change and emerging research feedback for Korean National Long Term Ecological Research (KNLTER)

        Cho, Yong-Chan,Lee, Chang-Seok,Cho, Hyun-Je,Lee, Kyu-Song,Park, Pil-Sun The Ecological Society of Korea 2011 Journal of Ecology and Environment Vol.34 No.1

        Various responses of forest ecosystems to climate change underscore the need to improve our understanding of the environmentally-driven changes in forests, most effectively by long-term monitoring protocols. We have explored vegetation dynamics based on changes in community structure, species composition, diversity and demographics in four Korean National Long Term Ecological Research (KNLTER) sites--Mt. Nam, Mt. Jeombong, Mt. Worak, and Mt. Jiri--between 2004 and 2009. Most of the sites and forests studied exhibited increments in total basal area, but this was not observed in Quercus mongolica forests in Mt. Nam and Mt. Worak. Stem density exhibited various changes. Altitude gradient was the representative factor in differences in species composition. Two patterns of compositional change--convergence and divergence--were detected. The vegetation of Mt. Nam and Q. mongolica community of Mt. Work showed relatively larger changes in composition. However, in the other sites, few changes were observed. Changes of species richness were not notable except for Mt. Nam, where three species were added in the pine forest, whereas one species disappeared in the oak forest. In the oak forests, mortality rate was as follows (in descending order): Mt. Nam (25.5%), Mt. Jeombong (24.3%), Mt. Worak (16.4%) and Mt. Jiri (0.8%). In the pine forest, the recruitment rate was as follows (in descending order): Mt. Nam (63.7%), Mt. Worak (12.9%), Mt. Jeombong (7.6%) and Mt. Jiri (7.3%). The mortality rate and change rate of basal area were strongly negatively correlated (r = -0.9, P = 0.002), and the recruitment rate and change rate of density were positively correlated (r = 0.77, P = 0.026). In the KNLTER sites, larger vegetation changes were attributed to anthropogenic activities such as salvage logging. Suppression or competition for resources would also affect these changes. Research suggestions such as monitoring to clarify the causes of species mortality were discussed.

      • Aflatoxin B_1 투여가 急性 肝 病變에 미치는 영향에 對한 病理學的 硏究

        장선문,이충식,강대영 충남대학교 의과대학 지역사회의학연구소 1989 충남의대잡지 Vol.16 No.1

        In an attempt of elucidate the pathologic and histochemical changes of aflatoxin B_2-induced hepatie lesions, the present study in male Sprague-Dawley rats was undertaken to evalute the relation between pathologic change of the liver and histochemical changes of several enzymes : alkaline phosphatase, acid phosphatase and succinic dehydrogenase at 3. 9. 24. 48. 72, and 144 hours after single administration of aflatoxin B_1 by gastric tube. The aflatoxin B_1 was dissolved in peanut oil(0.5㎎ aflatoxin B_1 to 0.5ml peanut oil). Grouop of male rats received aflatoxin B_1 1㎎ per ㎏ of body weight, respectively. Control animals were given a similar volume of peanut oil alone. The results on morphologic and histochemical changes were as follows: 1. The necrotic change of liver was mainly periportal, and it became most severe at 24 hours and was more prominent in the large dose group than the small dose group. 2. Biliary ductular cell proliferation started to appear within 72 hours and after became regressed later in the small dose group, but it remained approximately 144 hours after exposure in the large dose group. 3. Electron microscopically, all three groups showed irregular nuclear membrane and nucleolar change characterized by segregation of granular and fibrillar elements. All the group showed cytoplasmie changes such as dilatation of rough endoplasmic reticulum with detached ribosome, hyperplasia of smooth endoplasmic reticulum, increased numbers of lipid droplets and mitochondrial alteration. The above change in the large dose group was more severe than those of the small dose group. 4. In the histochemical study of experimental animals, there was a decrease in the intensity of the staining reaction of alkaline phosphatase and succinic dehydrogenase within 24 hours and a progressive decrease in staining intensity was noted at 144 hours. And then the staining intensity of the acid phosphatase was similar to that shown by the control animal. In summary, the data obtained by present experiments indicate aflatoxin B_1 exerts periportal necrosis of hepatic lobules accompanied by bile ductular cell proliferation, and inhibition of protein synthesis, as jedged by elertron microscopic and histochemical changes.

      • KCI등재

        보조호르몬요법을 받는 여성 유방암 환자의 모발 변화와 치료 실태에 대한 기초 연구

        이재경 ( Jae Kyung Lee ),김창현 ( Chang-hyun Kim ),홍동균 ( Dongkyun Hong ),정경은 ( Kyung Eun Jung ),서영준 ( Young-joon Seo ),김창덕 ( Chang-deok Kim ),이진선 ( Jin Sun Lee ),권인선 ( In Sun Kwon ),박상현 ( Sanghyun Park ),이영 대한피부과학회 2021 대한피부과학회지 Vol.59 No.7

        Background: Hormone therapy, which includes tamoxifen and aromatase inhibitors, is the most common adjuvant therapy used for breast cancer. However, only a few studies have reported endocrine therapy induced alopecia. Objective: We investigated the effects of long-term adjuvant hormone therapy on hair in patients with breast cancer, in addition to patients’ concerns and current treatment for hair loss. Methods: Patients completed a questionnaire that included information on self-perceived hair changes after each adjuvant therapy session, distress, and current treatment for hair loss. Using a folliscope, we measured hair density and thickness in each patient and in healthy controls. Results: The study included 93 patients with breast cancer (mean age 51.9±9.8 years). The density and hair thickness were 106.36±21.85 hairs/cm2 and 0.07±0.01 mm in the patient group and 147.86±30.67 hairs/cm2 and 0.07±0.01 mm in the control group (n=98, mean age 52.10±8.40 years), respectively. The mean hair density was significantly lower in the patient group than in the control group; however, no statistically significant intergroup difference was observed in hair thickness. Among 76 patients who perceived hair changes after adjuvant therapy, 71.1% (n=54) were distressed with regard to hair changes. However, only 7.8% of the patients, including two who were treated by dermatologists, currently received treatment for hair changes. Conclusion: Dermatologists should be familiar with hair changes in patients with breast cancer and provide appropriate education to encourage patients to consult dermatologists for hair loss and thinning after breast cancer treatment. (Korean J Dermatol 2021;59(7):521∼526)

      • KCI등재

        전통주 주박의 항혈전 활성 평가

        김미선(Mi-Sun Kim),이예슬(Ye-Seul Lee),김종식(Jong Sik Kim),신우창(Woo-Chang Shin),손호용(Ho-Yong Sohn) 한국생명과학회 2014 생명과학회지 Vol.24 No.8

        전통주 주박을 이용한 고부가가치 식품소재 개발을 위해, 상업적 시설에서 생산된 3종 약주(J-B, J-S, J-Y) 및 2종 탁주(J-H, J-W) 주박의 ethanol 추출물 및 열수 추출물을 조제하고 이들의 혈액응고 저해활성, 혈소판 응집저해 활성 및 인간 적혈구 용혈활성을 평가하였다. 5종 주박의 pH는 3.90~4.29로 유사하였으나, brix는 5.0~27.0으로 다양하게 나타났으며, 수분 및 알코올 함량에서도 시료에 따라 1.8배의 차이를 나타내었다. 주박의 색차와 성분은 첨가된 부재료 및 사용누룩에 좌우되었으며, J-W 주박의 경우 수분함량이 80.3%, brix 13, 알코올 함량 1.8%를 함유하여 다른 주박에 비해 다양한 식품제조에 용이하게 이용 가능하리라 판단되었다. Ethanol 추출효율은 J-H, J-W, J-B, J-S, J-Y의 순, 열수 추출효율은 J-S, J-B, J-W, J-H, J-Y의 순으로 높았으며, 총폴리페놀 및 총플라보노이드함량은 ethanol 추출물 중에서는 J-H, 열수 추출물 중에서는 J-Y 주박에서 가장 높았다. 5종 주박의 10종 추출물은 모두 5 mg/ml 농도까지 인간 적혈구에 대한 용혈활성이 나타나지 않았으며, J-B, J-S, J-Y의 약주 주박의 ethanol 추출물에서 유의적인 혈액응고저해 활성이 나타났으며, J-W 탁주 주박의 열수 추출물에서 thrombin 저해 활성과 J-B, J-S 및 J-H 주박 열수 추출물에서 혈액 응고인자 저해활성을 확인하였다. 혈소판 응집저해 활성평가의 경우 J-W 탁주 주박의 ethanol 및 열수 추출물에서만 아스피린에 필적하는 우수한 활성이 확인되었다. 본 연구결과는 다양한 약주 및 탁주 주박이 항혈전 활성을 가지고 있으며, 주박으로부터 항혈전제 개발이 가능함을 제시하고 있다. In this study, ethanol and hot water extracts of lees from Korean traditional wine (J-B, J-S, J-Y, J-H, and J-W) were prepared, and their effects on blood coagulation, platelet aggregation, and hemolysis of human red blood cells (hRBCs) were investigated to develop functional food ingredients from lees. The pH and brix of the lees ranged from 3.90 to 4.29 and 5.0 to 27.0o, respectively, and there was a huge difference in the water and ethanol content among the lees. The nuruk and additives used affected the color and physicochemical properties of lees. The J-W takju made from only rice and traditional nuruk, which has 13o brix and 1.8% of alcohol, has potential as functional food ingredient. With regard to the extraction yields of lees, higher yields were obtained from J-H, which contains different medicinal plants, in ethanol, followed by J-W, J-B, J-S, and J-Y. Higher extraction yields of lees were obtained from J-S in hot water, followed by J-B, J-W, J-H, and J-Y, respectively. The ethanol extract of J-H and the hot water extract of J-Y had the highest contents of total polyphenol and total flavonoids among the lees extracts. The 10 lees extracts did not show hemolysis activity against hRBCs up to 5 mg/ml. In an anticoagulation activity assay, the ethanol extracts of three yakju lees (J-B, J-S, and J-Y) and the hot water extract of J-W inhibited thrombin activity, whereas the hot water extract of J-B, J-S, and J-H inhibited blood coagulation factors. In an antiplatelet aggregation activity assay, only the J-W takju lees showed significant inhibition activity. Our results suggest that lees from traditional wine had high potential as a novel antithrombosis agent.

      • Carotenoids 식이와 알코올이 혈액학적 성분과 간조직에 미치는 영향에 관한 연구

        조만희,김연선,이상한,우기민,장예진,김창세 순천향의학연구소 1999 Journal of Soonchunhyang Medical Science Vol.5 No.2

        Alcohol is well known agent which can damage the human tissues such as liver via stimulating lipid peroxidation and storage, denaturation of macromolecules, and inhibiting protein metabolism. On the other hand, carotenoids in addition to vitamins A, C, E and lipoic acid, play important roles in protecting these oxidative damages as well as preventing the production of free radicals. This study was carried out to elucidate the precise effects of alcohol administration into rats on the antioxidative functions of dietary carotenoids and isolated β-carotene, and to find out any parameters to uncover more detailed biochemical mechanisms of these agents. For these purposes, two different approaches were performed: 1) examination of the changes in hematological parameters (e.g., total proteins, A/G ratio, ALT/AST et. al) and statistical correlations among inter- and intragroups, 2) examination of the histopathological changes by an electron microscope. The results were analyzed and summarized as following; (1) Carrot diet for one week caused a slight increase in albumin. A/G ratio and AST levels, and a slight decrease in ALT, ALP, BUN and uric acid levels. Two-week alcohol administration following carrot diet increased total proteins, albumin A/G ratio and BUN levels. However, both groups were shown to have little significant changes in cholesterol concentrations. (2) Cheese diet for one week caused a significant increase in total proteins, albumin, AST, ALP, uric acid and total cholesterol levels, and a significant decrease in A/G ratio and glucose concentrations. However, two-week β-carotene diet following cheese intake increased total proteins albumin, A/G ratio, BUN and total cholesterol levels, whereas AST, ALT, ALP and uric acid levels were decreased. (3) Alcohol administration for one week caused an increase in AST activities and a decrease in total proteins, albumin, ALT, ALP and BUN levels. A successive β-carotene diet following alcohol administration increased total proteins, albumin, ALT, ALP and BUN levels, whereas decreased AST and uric acid levels. However, there were not significant changes in A/G ratio, glucose and total cholesterol levels in both groups. (4) β-carotene diet for one week caused a slight increase in albumin, glucose, AST and uric acid levels, and a slight decrease in ALP and BUN levels. Two-weeks alcohol administration following β-carotene diet increased albumin, glucose, BUN and total cholesterol levels, whereas decreased AST, ALT, ALP and uric acid levels. (5) Although the pathological investigation on the liver did not reveal significant changes, cheese diet group (CH-BC/1-CH) was shown to have some lipid deposits. Some results were unexpected and different from typical hematological changes shown by other researchers. Nonetheless, these results strongly suggest that the liver damage or hepatism caused by alcohol intake affects many kinds of biochemical metabolisms, which results in significant changes in many hematological parameters. In addition, dietary carotenoid and isolated β-carotene were shown to have protective roles against the biochemical changes by alcohol intake.

      • SCOPUSKCI등재

        Causes and Predictive Factors Associated with "Diagnosis Changed" Outcomes in Patients Notified as Tuberculosis Cases in a Private Tertiary Hospital

        Kang, Byung Ju,Jo, Kyung-Wook,Park, Tai Sun,Yoo, Jung-Wan,Lee, Sei Won,Choi, Chang-Min,Oh, Yeon-Mok,Lee, Sang-Do,Kim, Woo Sung,Kim, Dong Soon,Shim, Tae Sun The Korean Academy of Tuberculosis and Respiratory 2013 Tuberculosis and Respiratory Diseases Vol.75 No.6

        Background: The aim of our study was to evaluate the "diagnosis changed" rate in patients notified as tuberculosis (TB) on the Korean TB surveillance system (KTBS). Methods: A total of 1,273 patients notified as TB cases on the KTBS in one private tertiary hospital in 2011 were enrolled in the present study. Patients were classified into three groups: "diagnosis maintained", "diagnosis changed" (initially notified as TB, but ultimately diagnosed as non-TB), and "administrative error" (notified as TB due to administrative errors). Results: Excluding 17 patients in the "administrative error" group, the "diagnosis maintained" and "diagnosis changed" groups included 1,097 (87.3%) and 159 patients (12.7%), respectively. Common causes of "diagnosis changed" were nontuberculous mycobacterial (NTM) disease (51.7%, 61/118), and pneumonia (17.8%) in cases notified as pulmonary TB, and meningitis (19.5%, 8/41) and Crohn's disease (12.2%) in cases notified as extrapulmonary TB. Being older than 35 years of age (odds ratio [OR], 2.18) and a positive acid-fast bacilli stain (OR, 1.58) were positive predictors and a TB-related radiological finding (OR, 0.42) was a negative predictor for a "diagnosis changed" result via multivariate logistic regression analysis in pulmonary TB cases. Conclusion: Because of a high "diagnosis changed" rate in TB notifications to the KTBS, the TB incidence rate measured by the KTBS may be overestimated. Considering the worldwide trend toward increased NTM disease, the "diagnosis changed" rate may increase over time. Thus, when reporting the annual TB notification rate in Korea, the exclusion of "diagnosis changed" cases is desirable.

      • SCOPUSKCI등재

        Causes and Predictive Factors Associated with “Diagnosis Changed” Outcomes in Patients Notified as Tuberculosis Cases in a Private Tertiary Hospital

        ( Byung Ju Kang ),( Kyung Wook Jo ),( Tai Sun Park ),( Jung Wan Yoo ),( Sei Won Lee ),( Chang Min Choi ),( Yeon Mok Oh ),( Sang Do Lee ),( Woo Sung Kim ),( Dong Soon Kim ),( Tae Sun Shim ) 대한결핵 및 호흡기학회 2013 Tuberculosis and Respiratory Diseases Vol.75 No.6

        Background: The aim of our study was to evaluate the “diagnosis changed” rate in patients notified as tuberculosis (TB) on the Korean TB surveillance system (KTBS). Methods: A total of 1,273 patients notified as TB cases on the KTBS in one private tertiary hospital in 2011 were enrolled in the present study. Patients were classified into three groups: “diagnosis maintained”, “diagnosis changed” (initially notified as TB, but ultimately diagnosed as non-TB), and “administrative error” (notified as TB due to administrative errors). Results: Excluding 17 patients in the “administrative error” group, the “diagnosis maintained” and “diagnosis changed” groups included 1,097 (87.3%) and 159 patients (12.7%), respectively. Common causes of “diagnosis changed” were nontuberculous mycobacterial (NTM) disease (51.7%, 61/118), and pneumonia (17.8%) in cases notified as pulmonary TB, and meningitis (19.5%, 8/41) and Crohn`s disease (12.2%) in cases notified as extrapulmonary TB. Being older than 35 years of age (odds ratio [OR], 2.18) and a positive acid-fast bacilli stain (OR, 1.58) were positive predictors and a TB-related radiological finding (OR, 0.42) was a negative predictor for a “diagnosis changed” result via multivariate logistic regression analysis in pulmonary TB cases. Conclusion: Because of a high “diagnosis changed” rate in TB notifications to the KTBS, the TB incidence rate measured by the KTBS may be overestimated. Considering the worldwide trend toward increased NTM disease, the “diagnosis changed” rate may increase over time. Thus, when reporting the annual TB notification rate in Korea, the exclusion of “diagnosis changed” cases is desirable.

      • SCOPUSKCI등재

        제왕절개술을 위한 경막외 마취시 술전 투여 수액이 신생아 혈당치에 미치는 영향

        이혜원,김선희,신정순,장성호,임혜자,채병국 대한마취과학회 1993 Korean Journal of Anesthesiology Vol.26 No.4

        It is common for patient undergoing cesarean section under epidural anesthesia to have lower blood pressure because of not only supine hypotension syndrome but vasodilation due to sympathetic blockade. So it is necessary to give large volume of fluid before perfarming epidural anesthesia to prevent hypotension. When we use the dextrose containing fluid for that purpose, newborn baby could have a high blood glucose at delivery and low blood glucose level due to high insulin level after birth. The authors examined the blood glucose level at delivery and two hours after birth following use of 5% dextrose in lactated Ringers solution(HD group, n=24) or lactated Ringers solution (HS group, n=24) for prevention of hypotension during epidural anesthesia for cesarean section. The results were as follows; 1) The total amount of fluid was 789.6±264.2 ml in HD group and 741.1±253.5 ml in HS group. 2) The glucose level of mother at delivery was 300.9±76.3 mg/dl in HD group and 98.7±24.6 mg/dl in HS group and there wastistical significance(p$lt;0.01). 3) In HD group, the glucose level of newborn baby was 212.2±57.2 mg/dl at delivery and 465.±20.3 mg/dl at 2 hours after birth. The change of amount during 2 hours after birth was highly related to the glucose level at birth. Higher level of glucose at birth, larger amount of change during 2 hours after birth. 4) In HS group, the glucose level of newborn baby was 66.8±10.2 mg/dl at birth and 67.0±12.1 mg/dl at 2 hours after birth. There was no significant change.

      • KCI등재후보

        2003년 국내 중증급성호흡기증후군 진료 현황 및 문제점 분석

        이진수,김은실,정문현,백제중,정선화,안주희,최영화,이선희,고철우,김성범,김민자,박승철,기현균,송재훈,최상호,김양수,이상오,조용균,박영훈,정숙인,김연숙,이흥범,손창희,장성희,정희진,김우주 대한감염학회 2004 감염과 화학요법 Vol.36 No.3

        목적 : 2002년 말 중국에서 SARS가 발생한 이후 국내에서도 2003년 10월까지 총 3명의 추정환자, 17명의 의심환자가 보고되었다. 향후 추가적인 SARS의 유행이 우려되는 상황에서, 그간의 SARS 환자 진료에 있어서의 실질적인 준비사항, 진료 현황 등에 대한 조사를 통해 문제점을 파악하여, 향후 더 나은 대비가 될 수 있도록 개선점을 제시하고자 하였다. 재료 및 방법 : SARS로 의심되는 환자를 진료 경험이 있는 병원의료진을 대상으로 2003년 10월에 설문조사를 실시하였다. 설문에는 SARS 환자 진료 시의 실질적인 조치, 진료 현황, 병실, 응급실 및 외래에서의 격리 시설과 준비사항, 보건당국의 관리와 지원에 관한 사항을 포함하였다. 결과 : 대상이 되는 22개 병원 중 17개(17/22, 77.2%) 병원이 설문에 응하였다. SARS 환자를 위한 격리실은 응급실, 외래, 일반병실 및 중환자실에서 각각 9개(9/17, 52.9%), 5개(5/17, 29.4%), 15개(15/16, 93.7%), 4개(4/16, 25%) 병원에서 음압처리가 되어있지 않은 일인실 혹은 다인실이 사용되었고, 1개(1/16, 6.3%) 병원에서만 일반병실에서 음압격리실이 운영되었다. 입원환자의 진찰 시 개인보호구의 착용은 거의 모든 의료기관에서 이루어졌다. 보건당국에서 SARS지정병원의 시설 등을 사전에 확인한 곳은 1곳(1/12, 8.3%)이였고, 14개 병원(14/15, 93.3%)에서는 보건당국에 의뢰한 검사결과를 통하 받지 못하였다. 결론 : 의료기관에서 SARS 환자용 격리실뿐만 아니라 기존의 격리실 설비 등이 미흡하였으며, 특히 중환자실 및 외래의 준비가 더욱 부족하였다. 보건당국의 의료기관에 대한 종합적인 지원이 부족하였고, 병원과의 원활한 연계가 잘 이루어지지 않았다. SARS 만이 아닌 격리를 필요로 하는 질환의 적절한 진료를 위해 향후 병원 시설의 정비와 정부차원에서의 보다 구체적이고 실질적인 대책마련이 필요하다. Background : There was an worldwide outbreak of the Severe Acute Respiratory Syndrome (SARS) originated from China in late 2002. During that period three cases of suspected SARS and 17 cases of probable SARS were reported in Korea. With the concerns about the reemergence of SARS-coV transmission, it is important to be prepared for any possibility. So, this study is aimed to analysis the past measures in managing SARS and propose the amendatory plans to improve the preparedness. Materials & Methods : Questionnaires were collected among clinicians with any experience in managing the probable or suspected SARS cases in Oct. 2003. 17 out of 22 hospitals responded to the questionnaire. The contents in the questionnaire were practical activities, personal equipments, response plans, isolation facilities in emergency centers, outpatient clinics, general wards and intensive care units, and relationship with the public health department. Results : The dedicated isolation rooms in emergency centers, outpatient clinics, general wards, and intensive care units were prepared in 9 (9/17, 52.9%), 5 (5/17, 29.4%), 15 (15/16, 93.7%), and 4 (4/16, 25.0%) hospitals, respectively. Except for one hospital that newly made negative pressure room for SARS, single or multi-bed rooms without airborne infection control were used in all the other hospitals. The personal precaution principles were kept quite well in general wards. Before the designation of SARS hospital by the public health department prior evalution to see if the hospital was suitable for managing SARS was conducted in only 1 (1/12, 8.3%) hospital. The results of laboratory diagnosis were reported back in 1 (1/15, 6.6%) hospital. Conclusions : The isolation facilities which can control airborne infection were almost deficient not only for SARS but also for other respiratory transmissible diseases. For the infection control of transmissible diseases including SARS, more investment is needed on medical facilities and comprehensive support from the public health department required.

      • SCIESCOPUSKCI등재

        Modeling of CO<sub>2</sub> Emission from Soil in Greenhouse

        Lee, Dong-Hoon,Lee, Kyou-Seung,Choi, Chang-Hyun,Cho, Yong-Jin,Choi, Jong-Myoung,Chung, Sun-Ok Korean Society of Horticultural Science 2012 원예과학기술지 Vol.30 No.3

        Greenhouse industry has been growing in many countries due to both the advantage of stable year-round crop production and increased demand for fresh vegetables. In greenhouse cultivation, $CO_2$ concentration plays an essential role in the photosynthesis process of crops. Continuous and accurate monitoring of $CO_2$ level in the greenhouse would improve profitability and reduce environmental impact, through optimum control of greenhouse $CO_2$ enrichment and efficient crop production, as compared with the conventional management practices without monitoring and control of $CO_2$ level. In this study, a mathematical model was developed to estimate the $CO_2$ emission from soil as affected by environmental factors in greenhouses. Among various model types evaluated, a linear regression model provided the best coefficient of determination. Selected predictor variables were solar radiation and relative humidity and exponential transformation of both. As a response variable in the model, the difference between $CO_2$ concentrations at the soil surface and 5-cm depth showed are latively strong relationship with the predictor variables. Segmented regression analysis showed that better models were obtained when the entire daily dataset was divided into segments of shorter time ranges, and best models were obtained for segmented data where more variability in solar radiation and humidity were present (i.e., after sun-rise, before sun-set) than other segments. To consider time delay in the response of $CO_2$ concentration, concept of time lag was implemented in the regression analysis. As a result, there was an improvement in the performance of the models as the coefficients of determination were 0.93 and 0.87 with segmented time frames for sun-rise and sun-set periods, respectively. Validation tests of the models to predict $CO_2$ emission from soil showed that the developed empirical model would be applicable to real-time monitoring and diagnosis of significant factors for $CO_2$ enrichment in a soil-based greenhouse.

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