• Title/Summary/Keyword: $O_2$ plasma

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A Study on Contact Dermatitis-Causing Substances Concentration in Commercial Oxidative Hair-Coloring Products (유통 산화형 염모제의 접촉성피부염 유발물질 함량 연구)

  • Na, Young Ran;Koo, Hee Soo;Lee, Seung Ju;Kang, Jung Mi;Jin, Seong Hyeon
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.40 no.2
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    • pp.203-214
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    • 2014
  • We measured the contact dermatitis-causing substances concentrations in 28 commercial oxidative hair-coloring products. This study was aimed to provide the fundamental data about oxidative hair-coloring products. We selected 10 oxidation dyes (p-phenylenediamine, toluene-2,5-diamine, m-phenylenediamine, nitro-p-phenylenediamine, p-aminophenol, m-aminophenol, o-aminophenol, p-methylaminophenol, N,N'-bis(2-hydroxyethyl)-p-phenylenediamine sulfate, 2-methyl-5-hydroxyethylaminophenol) and 4 heavy metal (nikel; Ni, chromium; Cr, cobalt; Co, copper; Cu) as contact dermatitis-causing substances. To identify 10 oxidation dyes, hexane-2% sodium sulfite was used for the rapid and simple extraction and ultra performance liquid chromatography (UPLC) analysis was used for simultaneous analysis in 12 minutes. 10 oxidative dyes were detected as indicated on the product packaging and each concentration was lower than prescribed upper concentration limit by pharmaceutical manufacturing standards. And we analysed inductively coupled plasma-optical emission spectrophotometer (ICP-OES) for content search of heavy metal after microwave digestion. The heavy metal average concentration in oxidative hair-coloring products was 0.572 ${\mu}g/g$ for Ni, 3.161 ${\mu}g/g$ for Cr, 2.029 ${\mu}g/g$ for Co, 0.420 ${\mu}g/g$ for Cu, respectively. The average of concentration in powder type (henna) was higher than those of other foam and cream type oxidative hair-coloring products as follows; 1.800 ${\mu}g/g$ for Ni, 10.127 ${\mu}g/g$ for Cr, 7.082 ${\mu}g/g$ for Co, 1.451 ${\mu}g/g$ for Cu. Hair coloring products were classified into the six colors - black, dark brown, brown, dark brown, light brown, red brown and analyzed. Brown color had the highest average concentration of Co and the others had the highest average concentration of Cr.

Property of Nickel Silicide with 60 nm and 20 nm Hydrogenated Amorphous Silicon Prepared by Low Temperature Process (60 nm 와 20 nm 두께의 수소화된 비정질 실리콘에 따른 저온 니켈실리사이드의 물성 변화)

  • Kim, Joung-Ryul;Park, Jong-Sung;Choi, Young-Youn;Song, Oh-Sung
    • Journal of the Korean Vacuum Society
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    • v.17 no.6
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    • pp.528-537
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    • 2008
  • 60 nm and 20 nm thick hydrogenated amorphous silicon(a-Si:H) layers were deposited on 200 nm $SiO_2$/single-Si substrates by inductively coupled plasma chemical vapor deposition(ICP-CVD). Subsequently, 30 nm-Ni layers were deposited by an e-beam evaporator. Finally, 30 nm-Ni/(60 nm and 20 nm) a-Si:H/200 nm-$SiO_2$/single-Si structures were prepared. The prepared samples were annealed by rapid thermal annealing(RTA) from $200^{\circ}C$ to $500^{\circ}C$ in $50^{\circ}C$ increments for 40 sec. A four-point tester, high resolution X-ray diffraction(HRXRD), field emission scanning electron microscopy(FE-SEM), transmission electron microscopy(TEM), and scanning probe microscopy(SPM) were used to examine the sheet resistance, phase transformation, in-plane microstructure, cross-sectional microstructure, and surface roughness, respectively. The nickel silicide from the 60 nm a-Si:H substrate showed low sheet resistance from $400^{\circ}C$ which is compatible for low temperature processing. The nickel silicide from 20 nm a-Si:H substrate showed low resistance from $300^{\circ}C$. Through HRXRD analysis, the phase transformation occurred with silicidation temperature without a-Si:H layer thickness dependence. With the result of FE-SEM and TEM, the nickel silicides from 60 nm a-Si:H substrate showed the microstructure of 60 nm-thick silicide layers with the residual silicon regime, while the ones from 20 nm a-Si:H formed 20 nm-thick uniform silicide layers. In case of SPM, the RMS value of nickel silicide layers increased as the silicidation temperature increased. Especially, the nickel silicide from 20 nm a-Si:H substrate showed the lowest RMS value of 0.75 at $300^{\circ}C$.

Preparation of ITO and Insulator Layer Using Shadow Mask Method

  • Seo, In-Ha;Lee, Jong-Ho;Choe, Beom-Ho
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.08a
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    • pp.321-323
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    • 2012
  • 유기 발광 다이오우드는(OLEDs) 자체 발광 소자로써 높은 시야각, 높은 효율, 그리고 빠른 응답속도 등의 장점을 가지고 있어 차세대 디스플레이 및 조명 소자로서 많은 연구가 진행되고 있다. 특히 유기 발광 다이오우드는 차세대 반도체 조명 소자로서 조명의 패러다임을 바꿀 수 있는 기술로 인식되고 있다. 하지만, 유기 발광 다이오우드 조명의 상용화를 위해서는 가격 경쟁력을 갖추는 것이 시급하며, 이를 위해 저가 공정 개발이 필요하다. 본 연구에서는 유기발광 다이오우드 조명 제작에 필수적인 전면 전극 및 절연막 증착 공정을 기존의 노광 공정이 아닌 shadow mask 기술을 적용하여 형성하였다. 먼저 유리 기판 상에 150 nm 두께의 ITO 막을 shadow mask를 이용하여 증착하였다. 기존 공정에서는 노광 및 식각 공정을 이용하여 증착하는 것이 일반적이며, 광학적, 전기적 특성 또한 타 공정 방법에 비해 우수하다. 하지만 일련의 복잡한 공정으로 인해 제조 원가를 상승 시키는 단점이 있다. Fig. 1은 shadow mask를 이용하여 ITO를 증착을 수행한 공정의 모식도이다. ITO 박막 증착 후 표면 거칠기 제어 및 면저항 제어를 위해 O2 plasma 처리와 RTA 공정을 추가 수행하였다. Fig. 2(a)는 플라즈마 처리 및 열처리 공정 수행 후에 측정한 표면 AFM 사진이다. 열처리 및 플라즈마 처리 후에 ITO 박막의 표면 거칠기는 10배 이상 향상되었으며, 이는 유기 발광 다이오우드 조명 소자의 전면 투명 전극으로 사용되기에 적합한 값이다. 또한 전기적 특성 중 하나인 면저항 값은 열처리 및 플라즈마 처리 전/후의 값에서 많은 차이를 보인다. 표면 거칠기가 향상됨에 따라 면저항 값 역시 향상되는 결과를 보여주는데, 표면 처리전후의 면저항 값은 각각 28.17, 13.18 ${\Omega}/{\Box}$이다. 일반적으로 유기 발광 다이오우드의 전면 투명 전극으로 사용되기 위해서는 15 ${\Omega}/{\Box}$이하의 면저항 값이 필요한데, 표면 처리 후의 면저항값들은 이로한 조건을 만족한다. Fig. 3은 shadow mask 기술을 이용하여 절연막까지 형성한 유기 발광 다이오우드 소자의 전자 현미경 사진으로, 기존의 공정을 이용한 경우와 큰 차이는 없으며, 다만 shadow tail이 약 $30{\mu}m$ 정도 발생함을 확인할 수 있다. 절연막의 특성 평가 기준인 누설 전류 밀도는 $10-5A/cm^2$으로 기존의 공정을 이용한 경우에 비해 95% 수준으로서 shadow mask를 이용한 공정이 기존의 노광 및 식각 공정을 이용한 경우에 비해 공정 수는 9개가 단축됨에도 불구하고, 각 증착 박막의 특성에는 큰 차이가 없음을 알 수 있다.

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Studies on Several Hormone Responses Following Intravenous Alimentation - II. Insulin-and growth hormone responses following oral or intravenous alimentation in patient with far advanced gastric cancer (영양물 정주시의 체내호르몬 반응에 관한 연구 - II. 위암환자에서 본 영양물 투여시의 insulin 및 HGH 반응)

  • Sung, H.K.;Koh, J.H.;Ryu, Y.W.;Lee, J.O.;Lee, C.W.;Kim, J.Y.;Lee, J.K.
    • The Korean Journal of Nuclear Medicine
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    • v.9 no.2
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    • pp.23-28
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    • 1975
  • Glucose tolerance, insulin and growth hormone responses following glucose or amino acids administration by means of parenteral or oral load were studied in patients with far advanced gastric cancer. Hormone responses following nutrients load showed in patients with gastric cancer were compared to those of healthy subjects. Results were as follows: 1. Blood sugar appearance following oral glucose administration was diminished in patients with far advanced gastric cancer. 2. The insulin responses of gastric cancer following oral glucose were also diminished as compared to that of normal subjects and were identical with parenteral route. 3. Parenteral administration of glucose or amino acids to patients with gastric cancer result ed in a increase of plasma growth hormone level. 4. Lower insulin response to amino acids was observed on parenteral administration in patient with gastric cancer as in healthy subjects. 5. Author discussed that the low insulin response after oral glucose administration showed in gastric cancer, and any additional insulin requirement arise when longer periods of parenteral amino acid administration are necessary, as in the patient with malnutritions.

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Clinical Practice Guideline for the Treatment of Traumatic Shock Patients from the Korean Society of Traumatology

  • Jung, Pil Young;Yu, Byungchul;Park, Chan-Yong;Chang, Sung Wook;Kim, O Hyun;Kim, Maru;Kwon, Junsik;Lee, Gil Jae;Korean Society of Traumatology (KST) Clinical Research Group
    • Journal of Trauma and Injury
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    • v.33 no.1
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    • pp.1-12
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    • 2020
  • Purpose: Despite recent developments in the management of trauma patients in South Korea, a standardized system and guideline for trauma treatment are absent. Methods: Five guidelines were assessed using the Appraisal of Guidelines for Research and Evaluation II instrument. Results: Restrictive volume replacement must be used for patients experiencing shock from trauma until hemostasis is achieved (1B). The target systolic pressure for fluid resuscitation should be 80-90 mmHg in hypovolemic shock patients (1C). For patients with head trauma, the target pressure for fluid resuscitation should be 100-110 mmHg (2C). Isotonic crystalloid fluid is recommended for initially treating traumatic hypovolemic shock patients (1A). Hypothermia should be prevented in patients with severe trauma, and if hypothermia occurs, the body temperature should be increased without delay (1B). Acidemia must be corrected with an appropriate means of treatment for hypovolemic trauma patients (1B). When a large amount of transfusion is required for trauma patients in hypovolemic shock, a massive transfusion protocol (MTP) should be used (1B). The decision to implement MTP should be made based on hemodynamic status and initial responses to fluid resuscitation, not only the patient's initial condition (1B). The ratio of plasma to red blood cell concentration should be at least 1:2 for trauma patients requiring massive transfusion (1B). When a trauma patient is in life-threatening hypovolemic shock, vasopressors can be administered in addition to fluids and blood products (1B). Early administration of tranexamic acid is recommended in trauma patients who are actively bleeding or at high risk of hemorrhage (1B). For hypovolemic patients with coagulopathy non-responsive to primary therapy, the use of fibrinogen concentrate, cryoprecipitate, or recombinant factor VIIa can be considered (2C). Conclusions: This research presents Korea's first clinical practice guideline for patients with traumatic shock. This guideline will be revised with updated research every 5 years.

대기압 유전체 배리어 방전을 이용한 폴리머 박막의 증착과 특성 분석에 대한 연구

  • Kim, Gi-Taek;Suzaki, Yoshifumi;Kim, Yun-Gi
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2011.10a
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    • pp.38.2-38.2
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    • 2011
  • 폴리머 박막은 그 고유한 특성으로 인해 여러 산업적으로 널리 사용되고 있는 재료이다 예로 의약품이나 식품 포장지의 배리어, 전자부품의 절연체, 반도체 공정에서의 사용, 혹은 부식방지를 위해 사용 되어지기도 한다. 이 폴리머 박막을 증착 하기 위한 방법으로 이전부터 CVD (Chemical Vapor Deposition) 방법이 많이 사용되었고 지금까지도 가장 많이 사용되는 방법이다. CVD를 사용하여 $SiO_2$-like 필름의 증착은 전구체(precursor)로 Silane ($SiH_4$)을 사용하였으며, 플라즈마 발생 소스(source)로 열 혹은 전기장 등을 사용 하며 공정 시 압력 또한 대부분 저압 하에서 실시 하였다. 이와 같은 이전 CVD 방법의 문제는 사용되는 Silane 자체가 인체에 해로울 정도로 독성이 있으며 폭발성도 같이 가지고 있어 작업환경의 위험성이 높으며 열을 사용한 CVD의 경우 높은 공정 온도로 인해 증착 할 수 있는 대상이 제한 되어 지며 높은 열의 발생을 위해 많은 에너지의 소비가 필요하다. 저압 플라즈마를 사용한 CVD 는 공정상 높은 열의 발생이 일어나지 않아 기판 운용상 문제가 되지 않지만 저압 환경에서 해당 공정이 이루어기 때문에 인해 필수적으로 고가의 진공 챔버가 필수적이며 저압을 유지할 고가의 진공 펌프나 추가 장비들이 필요하게 된다, 또한 챔버 내에서 이루어지는 공정으로 인해 공정의 연속성이 떨어져 시잔비용 또한 많이 잡아 먹는다. 이러한 열 혹은 저압 플라즈마등을 사용한 공정의 단점을 해결하기 위해 여러 연구자들이 다양한 방법을 통해 연구를 하였다. 대기압 유전체 배리어 방전(AP-DBD: Atmospheric Pressure-Dielectric Barrier Discharge)을 사용한 폴리머 박막의 증착은 이전 전통적인 방법에 비해 낮은 장비 가격과 낮은 공정 온도 그리고 연속적인 공정 등의 장점이 있는 폴리머 박막 증착 방법 이다. 대기압 유전체 배리어 방전 공정 변수로 공급 전압 및 주파수 그리고 공급 전압의 영향, 전구체를 유전체 배리어 방전 전극으로 이동 시키기 위해 사용된 캐리어 가스의 종류 및 유량, 화학양론적 계수를 맞추기 위해 같이 포함되는 산소 가스의 유량, DBD 전극의 형태에 따른 증착 박막의 균일성 등 이 존재하며 이런 많은 변수 들에 대한 연구가 진행 되었지만 아직 이 대기압 DBD를 이용한 폴리머 박막의 증착에 대한 명확한 이해는 아직 완전 하다 할 수 없다. 본 연구에서는 이러한 대기압 DBD를 이용하여 폴리머 박막의 증착시 영향을 미치는 많은 공정 변수 등이 박막생성에 미치는 영향과 증착된 박막의 성질에 대한 연구를 진행 하였다.

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Bioequivalence of Terbinex Tablet to Lamisil Tablet (Terbinafine 125mg) (라미실 정(테르비나핀 125mg)에 대한 터비넥스 정의 생물학적동등성)

  • 고현철;홍정희;신인철
    • Biomolecules & Therapeutics
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    • v.11 no.1
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    • pp.65-71
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    • 2003
  • Terbinafine is a synthetic allylamine that is available in an oral formulation and is used at a dosage of 250mg/day. It is used as an active antifungal agent and inhibits the fungal enzyme squalene epoxidase, which leads to the accumulation of the sterol squalene, which is toxic to the organism. The purpose of the present study was to evaluate the bioequivalence of two terbinafine tablets, Lamisil (Novartis Korea Ltd.) and Terbinex (C-TRI Ltd.), according to the guidelines of Korea Food and Drug Administration (KFDA). Eighteen normal male volunteers, 26.00$\pm$2.57 year in age and 70.51$\pm$9.36 kg in body weight, were divided into two groups and a randomized 2${\times}$2 cross-over study was employed. After one tablet containing 125 mg of terbinafine was orally administered, blood was taken at predetermined time intervals and the concentrations of terbinafine in plasma were determined using HPLC with UV detector. Pharmacokinetic parameters such as AUC, $C_{max}$ and $T_{max}$ were calculated and ANOVA test was utilized for the statistical analysis of the parameters. The results showed that the differences in AUC, $C_{max}$ and $T_{max}$ between two tablets were -4.191%, 5.223% and -25.720%, respectively when calculated against the Lamisil, tablet. The powers (1-$\beta$) for AUC, $C_{max}$ and $T_{max}$ were 81%, 87% and below 60%, respectively. Minimum detectable differences(.il) at alpha=O.1 and 1-/3=0.8 were less than 20% (e.g., 19.72% and 17.77% for AUC and $C_{max}$, respectively). But minimum detectable differences($\Delta$) at alpha=0.1 and 1-$\beta$=0.8 for $T_{max}$ were more than 20% (e.g., 26.25%). The 90% confidence intervals were within $\pm$20% (e.g., -17.440∼9.06 and -6.713∼17.160 for AUC and $C_{max}$ respectively). But 90% confidence intervals for $T_{max}$ were not within $\pm$20% (e.g., -43.346∼8.083). Another ANOVA test was conducted for logarithmically transformed AUC and $C_{max}$. These results showed that there are no significant differences in AUC and $C_{max}$ between the two formulations: The differences between the formulations in these log transformed parameters were all for less than 20% (e.g., -4.19% and 5.22% for AUC and $C_{max}$, respectively). The 90% confidence intervals for the log transformed data were not the acceptance range of log 0.8 to log 1.25 in AUC but the acceptance range of log 0.8 to log 1.25 in $C_{max}$ (e.g., log 1.13∼log 1.50 and log 0.94-log 1.22 for AUC and $C_{max}$ respectively). The major parameters, AUC and $C_{max}$ met the criteria of KFDA for bioequivalence although $T_{max}$ did not meet the criteria of KFDA (1998 year) for bioequivalence, indicating that Onfran tablet is bioequivalent to Zofran tablet. But in another ANOVA test AUC did not meet the criteria of KFDA (2002) for bioequivalence but $C_{max}$ met the criteria of KFDA (2002 year) for bioequivalence.or bioequivalence.equivalence.equivalence.equivalence.

Thiopental Prevents A Beta-Endorphin Response to Cardiopulmonary Bypass (체외순환전 투여된 Thiopental이 Beta-endorphin치 변화에 미치는 영향)

  • Song, Sun-Ok;Carr, Daniel B.;Park, Dae-Pal;Jee, Dae-Lim;Kim, Sae-Yeon
    • Journal of Yeungnam Medical Science
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    • v.14 no.2
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    • pp.350-358
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    • 1997
  • We studied the effects of adding a single bolus(500 mg) of sodium thiopental to a continuous infusion of low-dose fentanyl on plasma beta-endorphin immunoreactivity(iBE) responses to cardiopulmonary bypass(CPB) in 28 patients undergoing elective coronary artery bypass grafting or valve procedures. Thiopental was injected just prior to the initiation of CPB. The iBE levels and the hemodynamic indices such, as mean arterial pressure, cardiac output and systemic vascular resistance were measured before CPB, at 30 min and again at 60 min after the initiation of the bypass. The results were as follows. After the initiation of CPB, iBE levels increased at 30 min and 60 min(P=0.006, P=0.004 respectively) in the control group, but not in the thiopental group. There were significant differences in the changes of iBE levels between the groups(F=8.7, G-G=0.002, P=0.001). The hemodynamic indices were similar in both groups. In conclusion, pretreatment with thiopental just before the initiation of CPB prevents the stress-induced beta-endorphin response to CPB.

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Characterization of Membrane Fouling and It's Optimal Chemical Cleaning Method in MF Process using D dam water (D댐수를 이용한 정밀여과 공정에서 막오염 특성 및 최적 화학세정방법 조사)

  • Kim, Chung H.;Lim, Jae L.;Lee, Byung G.;Chae, Seon H.;Park, Min G.;Park, Sang H.
    • Journal of Korean Society of Water and Wastewater
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    • v.21 no.5
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    • pp.559-569
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    • 2007
  • The purposes of this study were to find the main foulant of membrane and the optimal chemical cleaning method for MF(microfiltration) drinking water treatment system using D dam water as water source. The MF pilot plant which can treat maximum $500m^3/d$ consisted of 3 racks and was operated for 10 months under various operation conditions. After 10 months operation, $1^{st}$ and $2^{nd}$ rack of membrane pilot plant system were cleaned chemically and the degree of the restoration of the fouled membrane in terms of the pure water flux was detemnined. Inorganic compounds which contained in chemical cleaning waste was analyzed by Inductively Coupled Plasma (ICP). One membrane module for 3rd rack was disjointed and membrane fouling materials, especially inorganic compounds were investigated by Electron Probe Microanlysis (EPMA) to elucidate the reason of TMP increase. And also, the various chemical reagents (1N HCl or $H_2SO_4$, oxalic acid as acid and 0.3% NaOCl as alkali) were tested by combination of acid and alkali to determine the optimal chemical cleaning method for the MF system using micro-modules manufactured using the disjointed module. It was verified that the inside and outside of membrane module was colorized with black. As a result of the quantitative and semi-qualitative analysis of membrane foulant by ICP, most of inorganic foulant was manganese which is hard to remove by inorganic acid such as HCI. Especially, it was observed by EPMA that Mn was attached more seriously in inside surface of membrane than in outside surface of that. It was supposed that Mn fouling in inside surface of membrane might be caused by the oxidation of soluble manganese (Mn(II)) to insoluble manganese ($MnO_2$) by chlorine containing in backwashing water. The optimal cleaning method for the removal of manganese fouling was consecutive cleaning with the mixture of 1N HCl and 1% of oxalic acid, 0.3% NaOCl, and 1N HCl showing 91% of the restoration of the fouled membrane.

Effects of Chromium Yeast on Performance, Insulin Activity, and Lipid Metabolism in Lambs Fed Different Dietary Protein Levels

  • Yan, Xiaogang;Zhang, Wei;Cheng, Jianbo;Wang, Runlian;Kleemann, David O.;Zhu, Xiaoping;Jia, Zhihai
    • Asian-Australasian Journal of Animal Sciences
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    • v.21 no.6
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    • pp.853-860
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    • 2008
  • This experiment was conducted to study the effects of chromium (Cr), dietary crude protein (CP) level and potential interactions between these two factors on growth rate and carcass response, insulin activity and lipid metabolism in lambs. Forty-eight, 9-week-old weaned lambs (Dorper$\times$Small-tail Han sheep, mean initial body weight = $22.96kg{\pm}2.60kg$) were used in a $2{\times}3$ factorial arrangement of supplemental Cr (0 ppb, Cr0; 400 ppb, Cr1; or 800 ppb, Cr2 from chromium yeast) and CP levels (157 g/d to 171 g/d for each animal, LP; or 189 g/d to 209 g/d for each animal, HP). Growth data and blood samples were collected at the beginning and end of the feed trial, after which the lambs were killed. Both Cr additive groups and the HP group increased final weight and average daily gain, especially the Cr1 and HP group (p<0.01). HP increased pelvic fat weight (p<0.05), fat thickness of the 10th rib (p<0.05), longissimus muscle area (p<0.01) and rate of deposition of intramuscular fat (p<0.01). Supplemental Cr decreased the rate of deposition of intramuscular fat (p<0.05). Fasting insulin level and the ratio of insulin to glucose were lower with Cr1 than other groups, but with no significant difference. Glucose concentration was not affected by any treatment. Nonesterified fatty acids increased in the Cr1 (p<0.05) and HP (p<0.05) conditions and there was a significant $Cr{\times}CP$ interaction (p<0.05). Cr1 decreased triglycerides (p<0.05) and total cholesterol (p = 0.151) and HP increased high-density lipoprotein cholesterol (p<0.05). Cr1 decreased lipoprotein lipase activity in subcutaneous adipose tissue (aLPL, p<0.05) and the ratio of aLPL to lipoprotein lipase activity in skeletal muscle (mLPL, p = 0.079). mLPL and hepatic lipase (hHL) were not affected by any treatment. In the present study, Cr had limited effects on growth rate and carcass response, whereas Cr and CP had some notable effects on plasma metabolites and enzyme activities. Cr has a potential effect on energy modulation between lipid and muscle tissue. In addition, few $Cr{\times}CP$ interactions were observed.