• Title/Summary/Keyword: Difference-In-Difference (DiD)

Search Result 34, Processing Time 0.027 seconds

Reactive Extraction of Organic Acid with Amine Extractant, I. (A Study on the Effects of Extractant and Solvent on the Degree of Extraction in Reactive Extraction of Organic Acid) (아민 추출제에 의한 유기산의 반응추출(I) (유기산의 반응추출시 추출도에 미치는 추출제 및 용매의 영향에 관한 연구))

  • Ryu, Oon-Hyung;Lee, Han-Seob;Yoo, Chul-Hwi;Kim, Yong-Yeul;Kang, An-Soo
    • Applied Chemistry for Engineering
    • /
    • v.7 no.1
    • /
    • pp.203-213
    • /
    • 1996
  • In physical and reactive extraction system using equilibrium extraction equipment, the effects of extractants, concentration of extractant, and solvent on the degree of extraction were investigated. The organic acids used were acrylic acid and metacrylic acid. Extractants were n-octylamine(OA), di-n-octylamine(DOA), tri-n-octylamine(TOA) and tri-octylmetyl ammonium chloride(TOMAC ; Aliquat 336). We found that the degree of extraction for reactive extraction was 2~9 times than that for physical extraction and that effect of extractants on the degree of extraction of organic acid was the order of OA

  • PDF

A new analytical-numerical solution to analyze a circular tunnel using 3D Hoek-Brown failure criterion

  • Ranjbarnia, Masoud;Rahimpour, Nima;Oreste, Pierpaolo
    • Geomechanics and Engineering
    • /
    • v.22 no.1
    • /
    • pp.11-23
    • /
    • 2020
  • In this study, a new analytical-numerical procedure is developed to give the stresses and strains around a circular tunnel in rock masses exhibiting different stress-strain behavior. The calculation starts from the tunnel wall and continues toward the unknown elastic-plastic boundary by a finite difference method in the annular discretized plastic zone. From the known stresses in the tunnel boundary, the strains are calculated using the elastic-plastic stiffness matrix in which three dimensional Hoek-Brown failure criterion (Jiang and Zhao 2015) and Mohr-Coulomb potential function with proper dilation angle (i.e., non-associated flow rule) are employed in terms of stress invariants. The illustrative examples give ground response curve and show correctness of the proposed approach. Finally, from the results of a great number of analyses, a simple relationship is presented to find out the closure of circular tunnel in terms of rock mass strength and tunnel depth. It can be valuable for the preliminary decision of tunnel support and for prediction of tunnel problems.

The Effect of Newly Synthesized Compounds on the Photosynthetic Electron Transport of Cyanobacteria (Anacystis nidulans $R_2$) (신규(新規) 합성화합물들이 cyanobacteria의 광합성전자전달계에 미치는 영향)

  • Hwang, I.T.;Kim, J.S.;Cho, K.Y.;Yoneyama, K.;Yoshida, S.
    • Korean Journal of Weed Science
    • /
    • v.13 no.2
    • /
    • pp.89-95
    • /
    • 1993
  • The Inhibiting activity of newly synthesized phenol (E-series) and triazine (T-series) derivatives was evaluated by using thylakoid membranes extracted from cyanobacteria (Anacystis nidulans $R_2$). There were no significant differences between phenol derivatives and dinoseb to the thylakoid membrane extracted from wild type in the Hill reaction. However, a phenol derivative, E-24 which has no -Cl at phenyl ring, did not show any activity. The longer the length of R substituents was in phenol derivatives, the lower inhibiting activity was in the Hill reaction. Triazine derivatives, T-27, T-28, T-40, T-41, T-47 and T-48 were also compared with diuron and atrazine. Among triazine compounds, T-27 and T-28 showed 10 and 30 times activity as high as atrazine to wild type, respectively. Other triazine derivatives, T-40, T-41, T-47 and T-48 showed low inhibiting activity to wild and mutant type. A structural difference of T-27 and T-28 from T-40, T-41, T-47 and T-48 was the presented of -C-NH-. Both T-27 and T-28 were very closely associated with serine, an amino acid located at the 264th position of D1 protein because of the resistant ratio(R/S) to mutant G-264 were higher than that of atrazine.

  • PDF

MO Interpretation for Anticancer Activity of Pt-complexes (백금착물 (II) 의 항암성에 관한 분자궤도론적 해석 (제1보))

  • Byung-Kak Park;Yeo Hwhan-Jin
    • Journal of the Korean Chemical Society
    • /
    • v.29 no.4
    • /
    • pp.348-355
    • /
    • 1985
  • Extended Huckel Calculation of cis-and trans-dichloro diammine platinum(II), dichloroethylene diamine platinum(II) and their N-mono, di, tri and tetra-methylated or ethylated ones were carried out to investigate their anticancer activity. It was found that the net charge of two chlorine atoms in cis-isomers are greater than those in trans-ones and Pt-Cl bond energies of the former are less than that of the latter, indicating that Pt-Cl bond in cis-isomers has greater ionic character than that in trans-ones and Cl atoms in the former are easier to dissociated as Cl- than those in the latter. Also, the values of $b_{2g}-b_{1g}$ energy difference, ${\Delta}_1$ were found to be greater in cis-isomers than in trans-one without exceptions. For the substitution of methyl for H atom in ammine and ethylenediamine Pt-Cl bond strength shows the tendency to increase with increasing in number of methyl group. Accordingly, We believe that two Cl atoms in $PtLCl_2$-complexes (L: NH$_3$, en) are dissociated in the first step of the action of anticancer.

  • PDF

Optimizing Fat Grafting Using a Hydraulic System Technique for Fat Processing: A Time and Cost Analysis

  • Verdura, Vincenzo;Guastafierro, Antonio;Di Pace, Bruno;Faenza, Mario;Nicoletti, Giovanni Francesco;Rubino, Corrado
    • Archives of Plastic Surgery
    • /
    • v.49 no.2
    • /
    • pp.266-274
    • /
    • 2022
  • Background Many authors have researched ways to optimize fat grafting by looking for a technique that offers safe and long-term fat survival rate. To date, there is no standardized protocol. We designed a "hydraulic system technique" optimizing the relationship among the quantity of injected fat, operative time, and material cost to establish fat volume cutoffs for a single procedure. Methods Thirty-six patients underwent fat grafting surgery and were organized into three groups according to material used: standard, "1-track," and "2-tracks" systems. The amount of harvested and grafted fat as well as material used for each procedure was collected. Operating times were recorded and statistical analysis was performed to establish the relationship with the amount of treated fat. Results In 15 cases the standard system was used (mean treated fat 72 [30-100] mL, mean cost 4.23 ± 0.27 euros), in 11 cases the "1-track" system (mean treated fat 183.3 [120-280] mL, mean cost 7.63 ± 0.6 euros), and in 10 cases the "2-tracks" one (mean treated fat 311[220-550] mL, mean cost 12.47 ± 1 euros). The mean time difference between the standard system and the "1-track" system is statistically significant starting from three fat syringes (90 mL) in 17.66 versus 6.87 minutes. The difference between the "1-track" system and "2-tracks" system becomes statistically significant from 240 mL of fat in 15 minutes ("1-track") versus 9.3 minutes for the "2-tracks" system. Conclusion Data analysis would indicate the use of the standard system, "1-track," and "2-tracks" to treat an amount of fat < 90 mL of fat, 90 ÷ 240 mL of fat, and ≥ 240 mL of fat, respectively.

Effect of Coordination Environment on the Photophysical Properties of Luminescent Europium(III) Complexes

  • Baek, Nam-Seob;Kim, Yong-Hee;Lee, Dong-Hyun;Seo, Kang-Deuk;Kim, Hwan-Kyu
    • Bulletin of the Korean Chemical Society
    • /
    • v.30 no.7
    • /
    • pp.1553-1558
    • /
    • 2009
  • A series of Eu(III) complexes with various neutral ligands (2,2’:6’,2"-terpyridine (T), diglyme (D), 1N-(2-dimethylamino) ethyl)-1N, 2N, 2N-trimethylethane-1,2-diamine (PT), di-(2-picolyl)-amine derivative (HT), and multidentate terpyridine derivative (DT)) were synthesized to investigate the effect of coordination environment on the sensitized luminescence of Eu(III) complexes. The nine coordination sites of the $Eu^{3+}$ ion are occupied by three bidentate carboxylate moieties and one neutral ligand. The highest emission intensity is obtained for $Eu^{3+}$- $[NA]_3$ (PT), due to the difference in energy transfer efficiency and symmetry of the first coordination sphere of $Eu^{3+}$ ion. But, the lowest emission intensity is obtained for $Eu^{3+}$-$[NA]_3$(T). Terpyridine may not play an important role antenna for photosensitizing $Eu^{3+}$ ion. It could be attributed to the weak spectral overlap integral J value between its phosphorescence band and $Eu^{3+}$ion absorption band. Therefore, different coordination environment of $Ln^{3+}$ ion play an important role in providing sensitization of lanthanide ion emission.

Study of Philosophical Background of '虛' Described in "Huang Di Nei Jing" ("황제내경(黃帝內經)"의 '허(虛)'와 그 철학적 배경에 대한 연구)

  • Lee, Jin-Woo;Hong, Moo-Chang;Bae, Hyun-Su;Shin, Min-Kyu
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.20 no.4
    • /
    • pp.766-783
    • /
    • 2006
  • This study describes philosophical background regarding '虛' in oriental medicine in an effort to understand the relationships among some of the Eastern philosophy in accordance with differentiated meanings in several resources by analyzing examples of '虛' in Huang Di Nei Jing. The various usages of '虛' used in Huang Di Nei Jing are as follows: naming; condition of pulse; emptiness; '太虛' which was referred universal space by Chinese ; insufficiency, lack or scarcity, deficiency ; and the description of vitality, mental faculties. 外丹修煉(training by external substances) had the attitude do that withdraw the death by taking external materials. The meaning of '虛'in 外丹修煉 is similar to that in oriental medicine in terms of deficiency. That is, both 外丹修煉 and the oriental medicine consider that the death and disease are caused by the deficiency of something. However, there also exists difference between 外丹修煉 and the oriental medicine. 外丹修煉 supplements through withdrawal prohibition due to the characteristic of unchangeability and stern or immortal while oriental medicine provides concrete object of deficiency. 精(essence of life), 氣(ki, functional activity), and fe(vitality) not only have been considered as basic component of human body, but they also have been an important subject of health preservation for longevity with health in Taoism and oriental medicine. In oriental medicine, 精 and 氣 have been perceived as physical basis of human body and 神 as controller. 內丹修煉(Training of internal active substances) 掠nds to return to '虛', the early state of life through individual training, and attempts to withdraw death through continuous recurrence. The oriental medicine and 內丹修煉 held great value of 神 among health preservation of 精, 氣, and 神. They seek theoretical basis from philosophical Taoism. However, '虛' in Taoism is different from that in training by internal substances and oriental medicine: '虛' in philosophical Taoism has metaphysical concept which refers overcome of life and death, but '虛' in 內丹修煉 and oriental medicine have empirical concept. '太虛' is considered as formless space where it is emp Dut filled with 氣. It is conceptualized with the premise of the relevant adaptation of human body to natural environment theory referring that the interaction between the heaven and the earth makes changes; all creation is originated , and human is affected by the interaction of the heaven and the earth. Furthermore, in $\ulcorner$運氣七篇$\lrcorner$ (Seven chapters described about the five circuit phases and the six atmospheric influences), the expression that the earth is in the center of '太虛' and huge amount of 氣 supports it proves that $\ulcorner$運氣七篇$\lrcorner$ adapts '渾天設'(Chaotic universe thee). In Taoism, '虛' is the grounds where all creation is generated in the optimal condition of Tao. As regards the aspect of mentality, it is the condition in which one can free from the dualistic concepts such as right and wrong, beauty and ugliness, life and death, and so on. Although the ultimate goal of oriental medicine, the achievement of longevity without sickness, might contrast with the Taoist belief that perceives life and death as the natural phenomena or the flowing of the 氣, and eliminates all international, the idea of Taoism that one should live substantial life with naivety, and make Harmony with the nature might be influential to the oriental medicine.

Folic acid supplementation regulates key immunity-associated genes and pathways during the periparturient period in dairy cows

  • Khan, Muhammad Zahoor;Zhang, Zhichao;Liu, Lei;Wang, Di;Mi, Siyuan;Liu, Xueqin;Liu, Gang;Guo, Gang;Li, Xizhi;Wang, Yachun;Yu, Ying
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.33 no.9
    • /
    • pp.1507-1519
    • /
    • 2020
  • Objective: The current research was aimed to profile the transcriptomic picture of the peripheral blood lymphocytes (PBLs) associated with immunity in Chinese Holsteins supplemented orally with coated folic acid during the periparturient period. Methods: The total of 123 perinatal cows were selected for this study and divided into three groups; group A (n = 41, 240 mg/500 kg cow/d), group B (n = 40, 120 mg/500 kg cow/d) and group C (n = 42, 0 mg/cow/d) based on the quantity of folic acid fed. Three samples of PBLs were selected from each folic acid treated group (high, low, and control) and RNA sequencing method was carried out for transcriptomic analysis. Results: The analysis revealed that a higher number of genes and pathways were regulated in response to high and low folic acid supplementation compared to the controls. We reported the novel pathways tumor necrosis factor (TNF) signaling, antigen processing and presentation, Staphylococcus aureus infection and nuclear factor (NF)-kappa B signaling pathways) and the key genes (e.g. C-X-C motif chemokine ligand 10, TNF receptor superfamily member 1A, cluster difference 4, major histocompatibility complex, class II, DQ beta, NF-kappa-B inhibitor alpha, and TNF superfamily 13) having great importance in immunity and anti-inflammation in the periparturient cows in response to coated folic acid treatment. Conclusion: Collectively, our study profiled first-time transcriptomic analysis of bovine lymphocytes and compared the involved cytokines, genes, and pathways between high vs control and low vs control. Our data suggest that the low folic acid supplementation (120 mg/500 kg) could be a good choice to boost appropriate immunity and anti-inflammation as well as might being applied to the health improvement of perinatal dairy cows.

Weed Control in the Field of Cnidium officinale Makino (일천궁재배지(日川芎裁培地)의 효율적(效率的) 잡초방제(雜草防除) 방법(方法))

  • Kwon, Tae-Young;Jung, Ki-Chai;Park, No-Kwuan;Park, Sun-Do;Choi, Boo-Sull
    • Korean Journal of Medicinal Crop Science
    • /
    • v.5 no.4
    • /
    • pp.255-259
    • /
    • 1997
  • The effects of slow-release fertilizer, C. D. U. (cyclo-di-urea), vinyl mulching and herbicides in different combinations were tested for weed control as well as the growth and yield of Cnidium officinale and economics were analyzed. Black vinyl mulching, ethalfluralin EC+white vinyl mulching, and ethalfluralin EC controlled weed completely till 60days after planting. When pendimethalin GR was sprayed more than 4.5kg/10a weed control value was $93.7{\sim}97.3%$, so significant difference was recognized with the recommended application rate (3.0kg/10a).

  • PDF

Effect of machining precision of single ceramic restorations on the marginal and internal fit (단일 도재 수복물의 가공 정밀도가 변연 및 내면 적합도에 미치는 영향)

  • Son, Keunbada;Yu, Beom-Young;Lee, Kyu-Bok
    • The Journal of Korean Academy of Prosthodontics
    • /
    • v.58 no.4
    • /
    • pp.313-320
    • /
    • 2020
  • Purpose: The purpose of this study was to evaluate the machining precision and the marginal and internal fit of single restorations fabricated with three types of lithium disilicate ceramic blocks and to evaluate the correlation. Materials and methods: Single restorations were designed using a CAD software program. The crown designed model file was extracted from the CAD software program. Three types of lithium disilicate blocks (Rosetta; HASS, IPS e.max CAD; Ivoclar vivadent, VITA Suprinity; VITA) were milled using a milling machine. For the fabrication of the crown scanned model file, the intaglio surface of the restoration was digitized using a contact scanner. Then, using the three-dimensional inspection software (Geomagic control X; 3D Systems), the process of the overlap of the crown designed model and the scanned model and 3-dimensional analysis was conducted. In addition, the marginal and internal fit of the crowns was evaluated by a silicone replication method. The difference among three types of single ceramic crown was analyzed using a Kruskal-Wallis H test, and Spearman correlation analysis was performed to analyze the correlation between machining precision and fitness (α=.05). Results: There was a significant difference in the machining precision and the marginal and internal fit according to the type of ceramic block (P<.001). In addition, the machining precision and the marginal and internal fit were positively correlated (P<.001). Conclusion: The marginal fit of crowns fabricated according to the types of ceramic blocks was within the clinically acceptable range (< 120 ㎛), so it can be regarded as appropriate machining precision applicable to all clinical as aspects in terms of the marginal fit.