• 제목/요약/키워드: ACG

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Low Complexity Subcarrier Allocation Scheme for OFDMA Systems (OFDMA 시스템을 위한 저 복잡도 부반송파 할당기법)

  • Woo, Choong-Chae;Wang, Han-Ho
    • Journal of the Institute of Convergence Signal Processing
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    • v.13 no.2
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    • pp.99-105
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    • 2012
  • The focus of this paper is a proposal for a computationally efficient dynamic subcarrier allocation (DSA) algorithm for orthogonal frequency-division multiple access (OFDMA) systems. The proposed DSA algorithm considerably reduces the computational complexity and the amount of channel quality information (CQI) compared to amplitude craving greedy (ACG) algorithms, which use full CQI. At the same time, the performance of the proposed algorithm closely appear to ACG algorithms. Moreover, the authors present a new bandwidth-assignment algorithm produced by modifying bandwidth assignment based on the signal-to-noise ratio (BABS). This modified BABS algorithm enables the proposed DSA algorithm to produce a strong outage performance gain over the conventional scheme.

Evaluation of glycerol encapsulated with alginate and alginate-chitosan polymers in gut environment and its resistance to rumen microbial degradation

  • Gawad, Ramadan;Fellner, Vivek
    • Asian-Australasian Journal of Animal Sciences
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    • v.32 no.1
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    • pp.72-81
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    • 2019
  • Objective: To determine the effect of gut pH and rumen microbial fermentation on glycerol encapsulated in alginate and alginate-chitosan polymers. Methods: Glycerol was encapsulated at 2.5%, 5%, 7.5%, or 10% (w/w) with sodium alginate (A) and alginate-chitosan (AC) polymers. Surface morphology and chemical modifications of the beads were evaluated using scanning electron microscopy and Fourier transform infrared (FTIR) spectra. Encapsulation efficiency was determined at the 5% glycerol inclusion level in two experiments. In experiment 1, 0.5 g of alginate-glycerol (AG) and alginate-chitosan glycerol (ACG) beads were incubated for 2 h at $39^{\circ}C$ in pH 2 buffer followed by 24 h in pH 8 buffer to simulate gastric and intestinal conditions, respectively. In experiment 2, 0.5 g of AG and ACG beads were incubated in pH 6 buffer at $39^{\circ}C$ for 8 h to simulate rumen conditions. All incubations were replicated four times. Free glycerol content was determined using a spectrophotometer and used to assess loading capacity and encapsulation efficiency. An in vitro experiment with mixed cultures of rumen microbes was conducted to determine effect of encapsulation on microbial fermentation. Data were analyzed according to a complete block design using the MIXED procedure of SAS (SAS Institute, Cary, NC, USA). Results: For AG and ACG, loading capacity and efficiency were 64.7%, 74.7%, 70.3%, and 78.1%, respectively. Based on the FTIR spectra and scanning electron microscopy, ACG treatment demonstrated more intense and stronger ionic bonds. At pH 6, 36.1% and 29.7% of glycerol was released from AG and ACG, respectively. At pH 2 minimal glycerol was released but pH 8 resulted in 95.7% and 93.9% of glycerol released from AG and ACG, respectively. In vitro microbial data show reduced (p<0.05) fermentation of encapsulated glycerol after 24 h of incubation. Conclusion: The AC polymer provided greater protection in acidic pH with a gradual release of intact glycerol when exposed to an alkaline pH.

Development of Alginate-Celite Immobilization Technique for the Improvement of Ethanol Productivity (에탄올 생산성 향상을 위한 Alginate-Celite 고정화 방법의 개발)

  • 김승욱;김은영홍영기
    • KSBB Journal
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    • v.11 no.1
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    • pp.77-85
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    • 1996
  • The optimal initial pH for the ethanol production by Saccharomyces K35 was found to be 5.0, and about 80% of yield was obtained when 200g/$\ell$ of glucose was used as a substrate, which showed sugar tolerant. As the additives and cross-linking agent, the addition of 1.67%(w/v) Celite R-634 together with 0.33%(v/v) of glutaraldehyde(ACG bead) resulted in better stability, ethanol productivity and cell viability than Ca-alginate bead. Also, ACG bead seemed to be more resistant to phosphate ion than Ca-alginate bead, considering outgrowing cell concentration in the media. Scanning electron microscopic observation depicted that the surface of ACG bead was almost similar to the original state but not for Ca-alginate bead. When repealpd-batch culture was performed with Ca-alginate bead for 60 days in a 500m1 Erlenmeyer flask, ethanol and cell concentration were maintained about 138g/$\ell$-gel and 29~30g/$\ell$-gel, respectively, up to 40 days(7th run number), and then both were rapidly decreased. In the case of ACG bead, ethanol and cell concentration were maintained about 130~150g/$\ell$-gel and 32~35g/$\ell$-gel, respectively, up to 60days(10th run number). Cell viability was maintained about 70%, and outgrowing cell concentration was below 5.8% of total cell concentration.

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Aggressive Subchannel Allocation Algorithm for Optimize Transmission Efficiency Among Users in Multiuser OFDMA System (다중 사용자 OFDMA 시스템에서의 사용자간 전송효율 최적화를 위한 Aggressive Subchannel Allocation 알고리즘)

  • Ko Sang-Jun;Heo Joo;Chang Kyung-Hi
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.6A
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    • pp.617-626
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    • 2006
  • In this paper, we propose an ASA(Aggressive Subchannel Allocation) algorithm, which is an effective dynamic channel allocation algorithm considering all user's channel state to maximize downlink sector throughput in OFDMA system. We compare an ASA algorithm with Round Robin, ACG(Amplitude Craving Greedy), RCG(Rate Craving Greedy) and GPF(General Proportional Fair) in the 2-tier environment of FRF(Frequency Reuse Factor) 1 and then analyze the performance of each algorithms, through compute simulation. Simulation results show that the proposed ASA algorithm gets 58 %, 190 %, 130 % and 8.5 % better sector throughput compared with the Round Robin, ACG, RCG and GPF respectively.

A Study on Optimum Technics in Angiocardiography (심장혈관조영촬영(心臟血管造影撮影)의 촬영조건(撮影條件)에 대(對)한 검토(檢討))

  • Ahn, Bong-Seon
    • Journal of radiological science and technology
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    • v.4 no.1
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    • pp.37-44
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    • 1981
  • It is a experimental report to investigate optimum exposure technics in angiocardiography. Because of x-ray absorption and rapid voluntary motion in the heart region, it bound that discrimination ability of the exposed film is being decreased in ACG To circumvent these disadvantage it must be necessary to use short time exposure technics and also high capacity equipment in ACG. But in the case of using the low tube voltage to improve contrast on the exposed film, it will be result in a many difficulties in interpretation of the image due to increased contrast in vertebral images. Therefore the ranges 80 kVp to 90 kVp of could be suitable for the purpose of good contrast and an excellent discrimination ability and under this circumstance the optimum grid ratio for ACG was 8:1 to 12:1.

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Cortical thickness of the rostral anterior cingulate gyrus is associated with frailty in patients with end-stage renal disease undergoing hemodialysis in Korea: a cross-sectional study

  • Sang Hyun Jung;Jong Soo Oh;So-Young Lee;Hye Yun Jeong
    • Journal of Yeungnam Medical Science
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    • v.40 no.4
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    • pp.381-387
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    • 2023
  • Background: Frailty is defined as a condition of being weak and delicate, and it represents a state of high vulnerability to adverse health outcomes. Recent studies have suggested that the cingulate gyrus is associated with frailty in the elderly population. However, few imaging studies have explored the relationship between frailty and the cingulate gyrus in patients with end-stage renal disease (ESRD) undergoing hemodialysis. Methods: Eighteen right-handed patients with ESRD undergoing hemodialysis were enrolled in the study. We used the FreeSurfer software package to estimate the cortical thickness of the regions of interest, including the rostral anterior, caudal anterior, isthmus, and posterior cingulate gyri. The Beck Depression Inventory, Beck Anxiety Inventory, and laboratory tests were also conducted. Results: The cortical thickness of the right rostral anterior cingulate gyrus (ACG) was significantly correlated with the Fried frailty index, age, and creatinine level. Multiple regression analysis indicated that the cortical thickness of the right rostral ACG was associated with frailty after controlling for age and creatinine level. Conclusion: Our results indicate that the cortical thickness of the rostral ACG may be associated with frailty in patients with ESRD on hemodialysis and that the rostral ACG may play a role in the frailty mechanism of this population.

Primary angle-closure glaucoma, a rare but severe complication after blepharoplasty: Case report and review of the literature

  • Maria Kappen, Isabelle Francisca Petronella;Nguyen, Duy Thuan;Vos, Albert;van Tits, Hermanus Wilhelmus Hendricus Joseph
    • Archives of Plastic Surgery
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    • v.45 no.4
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    • pp.384-387
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    • 2018
  • Blepharoplasty is one of the most commonly performed aesthetic procedures. Surgical complications are rare, but can have severe consequences, such as permanent vision loss. In this report, we describe a patient who developed primary angle-closure glaucoma (ACG) with associated vision loss after a oculoplastic procedure using local anesthesia. So far, six similar cases have been described in the literature. It is believed that acute ACG is triggered by the surgical procedure in patients with predisposing risk factors such as a cataract. Surgical triggering factors include the use of buffered lidocaine/xylocaine with adrenaline/epinephrine, stress, and coverage of the eyes postoperatively. Due to postoperative analgesic use, the clinical presentation can be mild and atypical, leading to a significant diagnostic delay. Acute ACG should therefore be excluded in each patient with postoperative complaints by assessing pupillary reactions. If a fixed mid-wide pupil is observed in an ophthalmologic examination, an immediate ophthalmology referral is warranted. Surgeons should be aware of this rare complication in order to offer treatment at an early stage and to minimize the chance of irreversible vision loss.

Studies on the Oranization and Expression of tRNA Genes in Aspergillus nidulans (V) The Molecular Structure of $tRNA^{Arg}$ in Aspergillus nidulans (Aspergillus nidulans의 tRNA유전자의 구조와 발현에 관한 연구 V Aspergillus nidulansd의 $tRNA^{Arg}$ 분자구조)

  • 이병재;강현삼
    • Korean Journal of Microbiology
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    • v.24 no.2
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    • pp.79-85
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    • 1986
  • We have determined the sequence of $tRNA^{Arg}$ of A. nidulans partially by enzymatic rapid RNA sequencing technique. The sequence was 5'GGCCGGCUGGCCCAAXUGGCAAGGXUCUGAXUACGAAXCAGGAGAUUGCACXXXXXGAGCXXUXXGUCGGUCACCA3' The cloverleaf structure was made from above data. As a result, the anticodon sequence was identified as ACG. This result was confirmed with charging test. The complete sequence was proposed by supplementing the DNA sequence to and by assigning the position of minor bases to this RNA sequence.

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Effects of Two Traditional Chinese Cooking Oils, Canola and Pork, on pH and Cholic Acid Content of Faeces and Colon Tumorigenesis in Kunming Mice

  • He, Xiao-Qiong;Duan, Jia-Li;Zhou, Jin;Song, Zhong-Yu;Cichello, Simon Angelo
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.15
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    • pp.6225-6229
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    • 2015
  • Faecal pH and cholate are two important factors that can affect colon tumorigenesis, and can be modified by diet. In this study, the effects of two Chinese traditional cooking oils (pork oil and canola/rapeseed oil) on the pH and the cholic acid content in feces, in addition to colon tumorigenesis, were studied in mice. Kunming mice were randomized into various groups; negative control group (NCG), azoxymethane control group (ACG), pork oil group (POG), and canola oil Ggroup (COG). Mice in the ACG were fed a basic rodent chow; mice in POG and COG were given 10% cooking oil rodent chow with the respective oil type. All mice were given four weekly AOM (azoxymethane) i.p. injections (10mg/kg). The pH and cholic acid of the feces were examined every two weeks. Colon tumors, aberrant crypt foci and organ weights were examined 32 weeks following the final AOM injection. The results showed that canola oil significantly decreased faecal pH in female mice (P<0.05), but had no influence on feces pH in male mice (P>0.05). Pork oil significantly increased the feces pH in both male and female mice (P<0.05). No significant change was found in feces cholic acid content when mice were fed 10% pork oil or canola oil compared with the ACG. Although Kunming mice were not susceptible to AOM-induced tumorigenesis in terms of colon tumor incidence, pork oil significantly increased the ACF number in male mice. Canola oil showed no influence on ACF in either male or female mice. Our results indicate that cooking oil effects faecal pH, but does not affect the faecal cholic acid content and thus AOM-induced colon neoplastic ACF is modified by dietary fat.