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  • 제목/요약/키워드: Pulse-on duration

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플라즈마 강화 원자층 증착법에 의한 TaNx 박막의 전기 전도도 조절 (Electrical Conductivity Modulation in TaNx Films Grown by Plasma Enhanced Atomic Layer Deposition)

  • 류성연;최병준
    • 한국재료학회지
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    • 제28권4호
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    • pp.241-246
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    • 2018
  • TaNx film is grown by plasma enhanced atomic layer deposition (PEALD) using t-butylimido tris(dimethylamido) tantalum as a metalorganic source with various reactive gas species, such as N2+H2 mixed gas, NH3, and H2. Although the pulse sequence and duration are the same, aspects of the film growth rate, microstructure, crystallinity, and electrical resistivity are quite different according to the reactive gas. Crystallized and relatively conductive film with a higher growth rate is acquired using NH3 as a reactive gas while amorphous and resistive film with a lower growth rate is achieved using N2+H2 mixed gas. To examine the relationship between the chemical properties and resistivity of the film, X-ray photoelectron spectroscopy (XPS) is conducted on the ALD-grown TaNx film with N2+H2 mixed gas, NH3, and H2. For a comparison, reactive sputter-grown TaNx film with N2 is also studied. The results reveal that ALD-grown TaNx films with NH3 and H2 include a metallic Ta-N bond, which results in the film's higher conductivity. Meanwhile, ALD-grown TaNx film with a N2+H2 mixed gas or sputtergrown TaNx film with N2 gas mainly contains a semiconducting Ta3N5 bond. Such a different portion of Ta-N and Ta3N5 bond determins the resistivity of the film. Reaction mechanisms are considered by means of the chemistry of the Ta precursor and reactive gas species.

안정된 만성폐쇄성폐질환 환자의 기류제한 정도와 주관적 건강상태 (The Airflow Obstruction and Subjective Health Status Among Stable Chronic Obstructive Pulmonary Disease Patients Residing in the Community)

  • 송희영
    • Journal of Korean Biological Nursing Science
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    • 제19권1호
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    • pp.38-47
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    • 2017
  • Purpose: This study was undertaken to examine the relationship between airflow obstruction and subjective health status reported by stable patients with chronic obstructive pulmonary disease (COPD) residing in the community. Methods: A cross-sectional descriptive study was conducted with 78 stable COPD patients aged 69.7 years old on average and selected by a convenient sampling from an outpatient department of pulmonology in tertiary hospitals. They completed a constructed questionnaire including general characteristics, smoking history, dyspnea by modified medical research council (mMRC) scale, and health status by COPD assessment test (CAT). Anthropometric measurements were performed for body mass index (BMI) and pulse oxymetry for O2 saturation (Sat O2). Medical records were reviewed to obtain disease-related characteristics including duration of the disease, cardiovascular comorbidity, and forced expiratory volume in 1 second (FEV1). Data were analyzed using PASW statistics 20.0. Results: Mean FEV1 and CAT scores were 55.11% and 17.73, respectively. Those in the lower stage of mMRC showed significantly higher FEV1 and lower CAT. FEV1 and CAT showed significant negative correlations; age and BMI with FEV1, and Sat O2 with CAT. Conclusion: The findings suggest that the less airway obstruction was, the better health status was, and provide the support for using subjective measures in clinical practices for COPD patients.

Transformation of Bacillus stearothermophilus No. 236 by Changing Incubation Temperature after Electroporation

  • Ha, Gyong-Sik;Kim, Joon;Choi, Yong-Jin
    • Journal of Microbiology and Biotechnology
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    • 제9권5호
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    • pp.687-690
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    • 1999
  • Bacillus stearothermophilus No. 236 isolated from the soil is a strong xylan degrader producing all the xylanolytic enzymes. However, the strain was discovered to be highly intractable to its transformation. In the present study, we have developed a reliable method for transformation of B. stearothermophilus No. 236 by a systematic examination of several factors which might have an influence on the efficiency of electrotransformation. Notably, we found that the most critical factor influencing the transformation efficiency (TE) was the incubation temperature after pulsing, with its optimum incubation of 37C.At50C, the optimum growth temperature of the B. stearothermophilus strain, the transformants could not be obtained at a recognizable level. The combination of field strength of 7.5 kV/cm along with pulse duration of 10 msec (resistance of 400Ωandcapacitanceof25μF) was shown to be the best electrical parameters at the incubation temperature of 37. A higher TE was obtained when the cells were harvested at an early-exponential phase. Twenty percent of PEG-8000 in a suspension buffer and an addition of 0.1% glycine in the growth medium resulted in about 4-fold and 3-fold increases in TE, respectively. We also found that the plasmid DNA which had been cycled through the host B. stearothermophilus cells enhanced TE by one order of magnitude higher. Under the presently described conditions, $2.5{\times}10^{5} transformants per μg DNA was attained.

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아르곤 레이저 조사시 치근면 변화에 관한 주사 전자 현미경적 연구 (The Effects of the Argon Laser Irradiation on the Root Surface : A Scanning Electronic Microscopic Study)

  • 은희종;임성빈;정진형
    • Journal of Periodontal and Implant Science
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    • 제29권4호
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    • pp.861-872
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    • 1999
  • Since pathologic changes of exposed root surface inhibit cell attachment and new attachment of connective tissue have been made, many efforts were apply to change the exposed root surface condition. Scaling and root planing can not remove the endotoxin completely and forms the smear layer which prohibits the new attachment of connective tissue. Therefore, many kinds of chemicals were used for controlling the pathologic change of the root surface. The purposes of this study was to compare and observe the changes of the exposed root surface treated by scaling and root planning, Tetracycline HCl and Argon Laser. After the scaling and root planning of ten extracted premolars, the differences & the root surface among groups were observed under SEM. Control group showed smear layer and irregular amorphous surface. The dentinal tubule was not exposed. The debris and scale like texture were also observed. Tetracycline HCl treated group showed relatively smooth surface and the collagen fiber was observed in the dentinal tubule. Argon Laser treated group showed the most effective results under the conditions of 0.8 to 1.0w irradiation for 0.5 to 1.0 sec with pulse wave. The results of this study showed that the root surface change was associated with the intensity and the duration of Argon Laser irradiation. Further investigation for the surface change with the Argon Laser irradiation is recommended for understanding of clinical effect.

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교감신경 중재 통증 보유 모델 쥐에서 교감신경 활동에 의한 배근절세포의 흥분성 (Sympathetic Excitation of Afferent Neurons within Dorsal Root Ganglia in a Rat Model of Sympathetically Medicated Pain)

  • 임중우;강민정;백광세;남용택
    • The Korean Journal of Pain
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    • 제9권1호
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    • pp.26-38
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    • 1996
  • In a normal state, sympathetic efferent activity does not elicit discharges of sensory neurons, whereas it becomes associated with and excites sensory neurons in a pathophysiological state such as injury to a peripheral nerve. Although this sympathetic-sensory interaction is reportedly adrenergic, involved subtypes of adrenoreceptors are not yet clearly revealed. The purpose of this study was to determine which adrenorceptor subtypes were involved in sympathetic-sensory interaction that was developed in rats with an experimental peripheral neuropathy. Using rats that received a tight ligation of one or two of L4-L6 spinal nerves 10~15 days previously, a recording was made from afferent fibers in microfilaments teased from the dorsal root that was in continuity with the ligated spinal nerve. Electrical stimulation of sympathetic preganglionic fibers in T13 or L1 ventral root (50 Hz, 2-5 mA. 0.5 ms pulse duration, 10 sec) was made to see if the activity of recorded afferents was modulated. About half of afferents showing spontaneous discharges responded to sympathetic stimulation, and had the conduction velocities in the A-fiber range. Most of the sympathetically induced afferent responses were excitation. This sympathetically induced excitation occurred in the dorsal root ganglion (DRG), and was blocked by yohimbine (α2 blocker), neither by propranolol (β blocker) not by prazosine (α1 blocker). The results suggest that after spinal nerve ligation, sympathetic efferents interact with sensory neurons having A-fiber axons in DRG where adrenaline released from sympathetic nerve endings excites the activity of sensory neurons by acting on 2-adrenoreceptors. This 2-adrenoreceptor mediated excitation of sensory neurons may account for sympathetic involvement in neuropathic pain.

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Involvement of spinal muscarinic and serotonergic receptors in the anti-allodynic effect of electroacupuncture in rats with oxaliplatin-induced neuropathic pain

  • Lee, Ji Hwan;Go, Donghyun;Kim, Woojin;Lee, Giseog;Bae, Hyojeong;Quan, Fu Shi;Kim, Sun Kwang
    • The Korean Journal of Physiology and Pharmacology
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    • 제20권4호
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    • pp.407-414
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    • 2016
  • This study was performed to investigate whether the spinal cholinergic and serotonergic analgesic systems mediate the relieving effect of electroacupuncture (EA) on oxaliplatin-induced neuropathic cold allodynia in rats. The cold allodynia induced by an oxaliplatin injection (6 mg/kg, i.p.) was evaluated by immersing the rat's tail into cold water (4C) and measuring the withdrawal latency. EA stimulation (2 Hz, 0.3-ms pulse duration, 0.2~0.3 mA) at the acupoint ST36, GV3, or LI11 all showed a significant anti-allodynic effect, which was stronger at ST36. The analgesic effect of EA at ST36 was blocked by intraperitoneal injection of muscarinic acetylcholine receptor antagonist (atropine, 1 mg/kg), but not by nicotinic (mecamylamine, 2 mg/kg) receptor antagonist. Furthermore, intrathecal administration of M2 (methoctramine, 10μg) and M3 (4-DAMP, 10μg) receptor antagonist, but not M1 (pirenzepine, 10μg) receptor antagonist, blocked the effect. Also, spinal administration of 5HT3 (MDL-72222, 12μg) receptor antagonist, but not 5HT1A (NAN-190, 15μg) or 5HT2A (ketanserin, 30μg) receptor antagonist, prevented the anti-allodynic effect of EA. These results suggest that EA may have a significant analgesic action against oxaliplatin-induced neuropathic pain, which is mediated by spinal cholinergic (M2, M3) and serotonergic (5HT3) receptors.

족삼리(足三里), 상거허(上巨虛), 하거허(下巨虛)의 배혈(配穴)에 따른 전침(電鍼)의 실험적 연구 (Experimental Study of The Combined Effects of ST36, ST37, and ST39 Using Electroacupuncture)

  • 박민철;김대중;이호섭;조남근;주영승;육태한;유윤조;조은희
    • Journal of Acupuncture Research
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    • 제23권5호
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    • pp.79-92
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    • 2006
  • Acupuncture has acupoints to treat, prevent, and reduce disease and to recover health by meridian guidance and reflexion. In the oriental medicine, meridian and acupoints are the foundations of treatment. Therefore, in the clinical treatment, we have to decide the therapeutic methods, meridian, acupoints, acupoint place, and acupoint match according to the disease. This study was designed to investigate the combined effects of ST36, ST37, and ST39 using electroacupuncture in rats. The present study was conducted to see the effects produced by combined electro-acupuncture(EA) at ST36, ST37, and ST39 on small intestine transportation in rats. EA(2 Hz, 5mA, pulse duration 1 ms) was applied for 30 minutes at acupoints of ST36, ST37, and ST39. The results are as follows. Compared to other acupoint place matches, ST36(left)+ ST37(right), ST36(left)+ST39(right), and ST37(left)+ST39 (right) were more effective than ST36(right)+ST37(left), ST36 (right)+ST39(left), and ST37(right)+ST39(left) for small intestine transporation(+ means acupoint place match). In terms of acupoint placement, ST36(left), ST37(right), and ST39(right) were more effective than the other sides for small intestine transporation. The data suggests that we have to consider acupoint place and acupoint match for acupucture therapy.

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첨두 출력 1.5 kW급 준연속 이터븀 첨가 광섬유 레이저 (Quasi-continuous-wave Yb-doped Fiber Lasers with 1.5 kW Peak Power)

  • 전민지;정예지;김지원;정훈
    • 한국광학회지
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    • 제27권3호
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    • pp.95-100
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    • 2016
  • 본 논문에서는 이터븀(Yb)이 첨가된 이중 클래딩 광섬유를 이용한 고출력 고품질 준연속 레이저 시스템에 대한 연구 개발과 레이저 특성에 대해 보고한다. 이론적 수치 모사를 통해 최적화된 준연속 레이저 발진 조건을 찾았고, 그것을 바탕으로 공진기 구조와 MOPA (Master-Oscillator Power-Amplifier) 구조를 가진 광섬유 레이저 시스템을 각각 구축하였다. 두 레이저 시스템 모두 10 Hz 반복률, 10 ms로 작동시킬 때 최고 평균 출력 >150 W, 첨두 출력 >1.5 kW 이상의 준연속 레이저 빔을 발생시키는데 성공하였고, 레이저 발진 특성 및 빔 특성을 각각 비교하였다. 그리고 향후 더 높은 출력을 얻기 위한 방법과 전망에 대해 논의할 것이다.

Predictive score of uncomplicated falciparum malaria patients turning to severe malaria

  • Tangpukdee, Noppadon;Krudsood, Srivicha;Thanachartwet, Vipa;Duangdee, Chatnapa;Paksala, Siriphan;Chonsawat, Putza;Srivilairit, Siripan;Looareesuwan, Sornchai;Wilairatana, Polrat
    • Parasites, Hosts and Diseases
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    • 제45권4호
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    • pp.273-282
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    • 2007
  • In acute uncomplicated falciparum malaria, there is a continuum from mild to severe malaria. However, no mathematical system is available to predict uncomplicated falciparum malaria patients turning to severe malaria. This study aimed to devise a simple and reliable model of Malaria Severity Prognostic Score (MSPS). The study was performed in adult patients with acute uncomplicated falciparum malaria admitted to the Bangkok Hospital for Tropical Diseases between 2000 and 2005. Total 38 initial clinical parameters were identified to predict the usual recovery or deterioration to severe malaria. The stepwise multiple discriminant analysis was performed to get a linear discriminant equation. The results showed that 4.3% of study patients turned to severe malaria. The MSPS = 4.38 (schizontemia) + 1.62 (gametocytemia) + 1.17 (dehydration) + 0.14 (overweight by body mass index; BMI) + 0.05 (initial pulse rate) + 0.04 (duration of fever before admission)-0.50 (past history of malaria in last 1 year). 0.48 (initial serum albumin)-5.66. Based on the validation study in other malaria patients, the sensitivity and specificity were 88.8% and 88.4%, respectively. We conclude that the MSPS is a simple screening tool for predicting uncomplicated falciparum malaria patients turning to severe malaria. However, the MSPS may need revalidation indifferent geographical areas before utilized at specific places.

Chronic kisspeptin delays puberty and reduces feed intake and body weight in female rats

  • Sathagopam, Sriravali;Ullewar, Meenal Prabhakar;Harne, Rakhi;Velmurugan, Sathya
    • 한국동물생명공학회지
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    • 제36권1호
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    • pp.25-34
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    • 2021
  • Kisspeptin is a key player in the central control of reproductive axis. Central administration of kisspeptin has been shown to advance puberty in rats. Stimulation of hypothalamic GnRH pulse generating mechanism by kisspeptin has been proposed to be the mechanism behind the onset of puberty. We hypothesized that chronic high doses of kisspeptin administration suppresses the reproductive axis and hence delays the pubertal onset. Hence, we investigated the effect of peripheral administration of chronic high doses of kisspeptin on pubertal onset, feed intake and body weight in female rats. Rats were treated with saline or kisspeptin (100 nmoles per day; intraperitoneal) for 26 days (day 25 to day 50 postnatal) and the day of vaginal opening was marked as day of puberty. Kisspeptin treated rats had delayed pubertal onset and reduced feed intake and body weight. Gonadal GPR54 mRNA was reduced suggesting that chronic high doses of kisspeptin may suppress the reproductive functions possibly by downregulation of GPR54 receptor. However, delay in puberty due to reduction in feed intake and body weight could not be ruled out in this study. Further, our study emphasizes the importance of dosage and duration of kisspeptin administration in the manipulation of reproductive axis. Our study, for the first time, suggests that kisspeptin and its analogues, if proven beneficial, could be used to treat precocious puberty in children. It appears that, though a promising tool for enhancing fertility, kisspeptin acts as a double-edged sword and has to be cautiously used to manipulate reproduction.