Browsing by Issue Date, starting with "2013-10-02"

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Biomechanical comparison of three stand-alone lumbar cages - a three-dimensional finite element analysis
(2013-10-02)
Chen, Shih-Hao
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Chiang, Ming-Chieh
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Lin, Jin-Fu
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Lin, Shang-Chih
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Hung, Ching-Hua
Background: For anterior lumbar interbody fusion (ALIF), stand-alone cages can be supplemented with vertebral plate, locking screws, or threaded cylinder to avoid the use of posterior fixation. Intuitively, the plate, screw, and cylinder aim to be embedded into the vertebral bodies to effectively immobilize the cage itself. The kinematic and mechanical effects of these integrated components on the lumbar construct have not been extensively studied. A nonlinearly lumbar finite-element model was developed and validated to investigate the biomechanical differences between three stand-alone (Latero, SynFix, and Stabilis) and SynCage-Open plus transpedicular fixation. All four cages were instrumented at the L3-4 level. Methods: The lumbar models were subjected to the follower load along the lumbar column and the moment at the lumbar top to produce flexion (FL), extension (EX), left/right lateral bending (LLB, RLB), and left/right axial rotation (LAR, RAR). A 10 Nm moment was applied to obtain the six physiological motions in all models. The comparison indices included disc range of motion (ROM), facet contact force, and stresses of the annulus and implants. Results: At the surgical level, the SynCage-open model supplemented with transpedicular fixation decreased ROM (>76%) greatly; while the SynFix model decreased ROM 56-72%, the Latero model decreased ROM 36-91%, in all motions as compared with the INT model. However, the Stabilis model decreased ROM slightly in extension (11%), lateral bending (21%), and axial rotation (34%). At the adjacent levels, there were no obvious differences in ROM and annulus stress among all instrumented models. Conclusions: ALIF instrumentation with the Latero or SynFix cage provides an acceptable stability for clinical use without the requirement of additional posterior fixation. However, the Stabilis cage is not favored in extension and lateral bending because of insufficient stabilization.
Using Oxidized Low-Density Lipoprotein Autoantibodies to Predict Restenosis after Balloon Angioplasty in Patients with Acute Myocardial Infarction
(2013-10-03)
Huang, Ching-Hui
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Chang, Chia-Chu
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Huang, Ching-Shan
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Kuo, Chen-Ling
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Chen, Ching-Pei
Objectives: Oxidized low-density lipoproteins (oxLDL) and oxidized low-density lipoprotein autoantibodies (OLAB) have been detected in human plasma and atherosclerotic lesions. OLAB appear to play a role in the clearance of oxLDL from circulation. Higher levels of OLAB appear to be associated with a reduced risk of a wide range of cardiovascular diseases. We investigated the prognostic value of plasma oxLDL and OLAB in patients undergoing primary coronary balloon angioplasty for acute ST-elevation myocardial infarction (STEMI). Methods: Plasma oxLDL and OLAB concentrations were measured in 56 patients with acute STEMI before primary angioplasty, and then 3 days, 7 days and 1 month after the acute event. Follow-up angiography was repeated 6 months later to detect the presence of restensosis (defined as >50% luminal diameter stenosis). The thrombolysis in myocardial infarction (TIMI) risk score was calculated to determine the relationship between OLAB/oxLDL ratio and TIMI risk scores. Results: Of the 56 patients, 18 (31%) had angiographic evidence of restenosis. Plasma OLAB concentrations were significantly lower in the restenosis group before angioplasty (181 +/- 114 vs. 335 +/- 257 U/L, p = 0.003), and at day 3 (155 +/- 92 vs. 277 +/- 185 U/L, p<0.001) and day 7 (177 +/- 110 vs. 352 +/- 279 U/L, p<0.001) after the acute event. There was no difference in oxLDL concentration between the two groups. The ratio of OLAB/oxLDL positively correlated with TIMI risk scores before angioplasty (p for trend analysis, p = 0.004), at day 3 (p = 0.008) and day 7 (p<0.001) after STEMI. Significance: A relative deficit of OLAB, and hence likely impaired clearance of oxLDL, is associated with the risk of arterial restenosis after primary angioplasty for acute STEMI.
Ortho-Para Mixing Hyperfine Interaction in the H2O+ Ion and Nuclear Spin Equilibration
(2013-10-03)
Tanaka, Keiichi
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Harada, Kensuke
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Oka, Takeshi
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應用化學系
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Department of Applied Chemistry
The ortho to para conversion of water ion, H2O+, due to the interaction between the magnetic moments of the unpaired electron and protons has been theoretically studied to calculate the spontaneous emission lifetime between the ortho- and para-levels. The electron spin nuclear spin interaction term, T-ab(S-a Delta I-b + S-b Delta I-a) mixes ortho (I = 1) and para (I = 0) levels to cause the "forbidden" ortho to para vertical bar Delta I vertical bar = 1 transition. The mixing term with T-ab = 72.0 MHz is 4 orders of magnitude higher for H2O+ than for its neutral counterpart H2O where the magnetic field interacting with proton spins is by molecular rotation rather than the free electron. The resultant 10(8) increase of ortho to para conversion rate possibly makes the effect of conversion in H2O+ measurable in laboratories and possibly explains the anomalous ortho to para ratio recently reported by Herschel heterodyne instrument for the far-infrared (HIFI) observation. Results of our calculations show that the ortho <-> para mixings involving near-degenerate ortho and para levels are high (similar to 10(-3)), but they tend to occur at high energy levels, similar to 300 K. Because of the rapid spontaneous emission, such high levels are not populated in diffuse clouds unless the radiative temperature of the environment is very high. The low-lying 1(01) (para) and 1(11) (ortho) levels of H2O+ are mixed by similar to 10(-4) making the spontaneous emission lifetime for the para 1(01) -> ortho 0(00) transition 520 years and 5200 years depending on the F value of the hyperfine structure. Thus the ortho <-> para conversion due to the unpaired electron is not likely to seriously affect thermalization of interstellar H2O+ unless either the radiative temperature is very high or number density of the cloud is very low.
Systems-level Modeling with Molecular Resolution Elucidates the Rate-limiting Mechanisms of Cellulose Decomposition by Cellobiohydrolases
(2013-10-04)
Shang, Barry Z.
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Chang, Rakwoo
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Chu, Jhih-Wei
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生物科技學系
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生物資訊及系統生物研究所
Interprotein and enzyme-substrate couplings in interfacial biocatalysis induce spatial correlations beyond the capabilities of classical mass-action principles in modeling reaction kinetics. To understand the impact of spatial constraints on enzyme kinetics, we developed a computational scheme to simulate the reaction network of enzymes with the structures of individual proteins and substrate molecules explicitly resolved in the three-dimensional space. This methodology was applied to elucidate the rate-limiting mechanisms of crystalline cellulose decomposition by cellobiohydrolases. We illustrate that the primary bottlenecks are slow complexation of glucan chains into the enzyme active site and excessive enzyme jamming along the crowded substrate. Jamming could be alleviated by increasing the decomplexation rate constant but at the expense of reduced processivity. We demonstrate that enhancing the apparent reaction rate required a subtle balance between accelerating the complexation driving force and simultaneously avoiding enzyme jamming. Via a spatiotemporal systems analysis, we developed a unified mechanistic framework that delineates the experimental conditions under which different sets of rate-limiting behaviors emerge. We found that optimization of the complexation-exchange kinetics is critical for overcoming the barriers imposed by interfacial confinement and accelerating the apparent rate of enzymatic cellulose decomposition.
Fungal Small RNAs Suppress Plant Immunity by Hijacking Host RNA Interference Pathways
(2013-10-04)
Weiberg, Arne
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Wang, Ming
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Lin, Feng-Mao
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Zhao, Hongwei
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Zhang, Zhihong
Botrytis cinerea, the causative agent of gray mold disease, is an aggressive fungal pathogen that infects more than 200 plant species. Here, we show that some B. cinerea small RNAs (Bc-sRNAs) can silence Arabidopsis and tomato genes involved in immunity. These Bc-sRNAs hijack the host RNA interference (RNAi) machinery by binding to Arabidopsis Argonaute 1 (AGO1) and selectively silencing host immunity genes. The Arabidopsis ago1 mutant exhibits reduced susceptibility to B. cinerea, and the B. cinerea dcl1 dcl2 double mutant that can no longer produce these Bc-sRNAs displays reduced pathogenicity on Arabidopsis and tomato. Thus, this fungal pathogen transfers "virulent" sRNA effectors into host plant cells to suppress host immunity and achieve infection, which demonstrates a naturally occurring cross-kingdom RNAi as an advanced virulence mechanism.
Diastereoselective Synthesis of Bridged Polycyclic Alkaloids via Tandem Acylation/Intramolecular Diels-Alder Reaction
(2013-10-04)
Chen, Chih-Hau
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Yellol, Gorakh S.
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Tsai, Cheng-Hsun
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Dalvi, Prashant B.
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Sun, Chung-Ming
A mild and efficient stereoselective synthesis of hexacyclic indole alkaloids with a tetrahydro-beta-carboline motif has been developed by utilizing the Pictet-Spengler reaction and tandem N-acylation followed by intramolecular Diels-Alder cyclization. Initially, a diene unit was installed in the tetrahedron beta-carboline skeleton through Pictet-Spengler cyclization of the corresponding aldehyde with tryptophan ester. The dienophile moiety was introduced by N-acylation of tetrahydro-beta-carboline. Successive, in situ, [4 + 2] intramolecular Diels-Alder cycloaddition of the activated dienophile and conjugated diene containing intermediate furnished bridged polycyclic heterocycles with high diastereoselectivity. Formation of four new rings, five new covalent bonds, and five new chiral centers with excellent stereoselectivity is the key, feature of this strategy. The diastereoselective formation of product was attributed to intramolecular chirality transfer through a chiral amino acid. The stereoselective outcome of this tandem reaction was confirmed by X-ray crystallographic studies. The developed synthetic strategy was also explored on a soluble polymer support to incorporate the advantage of rapid synthesis and a high throughput workup process toward the development of a green synthetic protocol for polycyclic alkaloids.
The Post-Resuscitative Urinalysis Associate the Survival of Patients with Non-Traumatic Out-of-Hospital Cardiac Arrest
(2013-10-04)
Chang, Chin-Fu
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Li, Chao-Jui
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Ko, Chih-Jan
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Teng, Tsung-Han
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Lai, Shih-Chang
Objective: To analyze whether urine output and urinalysis results are predictive of survival and neurologic outcomes in patients with non-traumatic out-of-hospital cardiac arrest (OHCA). Methods: Information was obtained from 1,340 patients with non-traumatic OHCA who had achieved a sustained return of spontaneous circulation (ROSC). Factors that were associated with survival in the post-resuscitative period were evaluated. The association between urine output and fluid challenge in the early resuscitative period was analyzed and compared between the survivors and the non-survivors. The results of the initial urinalysis, including the presence of proteinuria and other findings, were used to evaluate the severity of vascular protein leakage and survival. The association between proteinuria and the neurologic outcomes of the survivors was also analyzed. The clinical features of capillary leakage were examined during the post-resuscitative period. Results: Of the 1,340 patients, 312 survived. A greater urine output was associated with a higher chance of survival. The initial urine output increased in proportion to the amount of fluid that was administered during early resuscitation in the emergency department for the survivors but not for the non-survivors (p<0.05). In the initial urinalysis, proteinuria was strongly associated with survival, and severe proteinuria indicated significantly poorer neurologic outcomes (p<0.05 for both comparisons). Proteinuria was associated with a risk of developing signs of capillary leakage, including body mass index gain and pitting edema (both p<0.001). Conclusion: The severity of proteinuria during the early post-resuscitative period was predictive of survival.
Rapid and highly sensitive detection of Enterovirus 71 by using nanogold-enhanced electrochemical impedance spectroscopy (vol 24, 285102, 2013)
(2013-10-04)
Li, Hsing-Yuan
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Tseng, Shing-Hua
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Cheng, Tsai-Mu
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Chu, Hsueh-Liang
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Lu, Yu-Ning
夢想一弦間　鄒世烈
(2013-10-06)
高紫娟
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Department of Communication and Technology
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傳播與科技學系
古典吉他手鄒世烈九月十一日才結束於國家演藝廳舉辦的獨奏會。對音樂有著不同的執著和堅持，非科班出身的他付出比別人更多的心血，才得以實現從小懷抱的吉他夢。
一道菜說人生　美味小影集
(2013-10-06)
許祐嘉
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Department of Communication and Technology
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傳播與科技學系
俗語說：「民以食為天。」從漫畫作品改編製作的日劇《深夜食堂》，到台灣偶像劇《沒有名字的甜點店》。食物除了提供人們營養，也可以是撫慰心靈的良藥，甚至是人的生活縮影，五味雜陳。
從眾文化　流行還是瘤形
(2013-10-06)
徐冠軒
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Department of Communication and Technology
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傳播與科技學系
現今台灣社會，到處充滿從眾現象的「一窩蜂」文化。由最近火紅的貓熊、黃色小鴨和路跑來看台灣民眾對於風潮的行為，究竟這種從眾文化對台灣是好是壞？讓我們看下去。
輕饒舌　慢嘻哈步曲
(2013-10-06)
游瑀萱
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Department of Communication and Technology
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傳播與科技學系
「如果有人，能夠將對嘻哈音樂有著刻板印象的聽眾，做出扭轉與改變，那麼我敢說，那個人，就是蛋堡。」從《收斂水》的俏皮，到《Winter Sweet》的溫馨，再到《你所不知道的杜振熙之內部整修》裡黑暗的他，蛋堡希望能藉著音樂，來呈現完整的「杜振熙」。
風箏升起　飄揚的青春
(2013-10-06)
陳韋琪
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Department of Communication and Technology
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傳播與科技學系
四個朋友，來自不同高中前往不同大學，卻因音樂而熟識，成為彼此最珍貴的陪伴。在音樂創作下，擁有各自特色的他們，互相切戳琢磨，激盪出非凡的火花。
女子歌劇院　日本少女心
(2013-10-06)
林婉婷
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Department of Communication and Technology
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傳播與科技學系
寶塚歌劇團在日本風靡百年，團裡的帥氣男役演出了日本少女理想的白馬王子，讓許多少女為之瘋狂。
總編輯的話
(2013-10-06)
聶薇庭
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Department of Communication and Technology
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傳播與科技學系
本期喀報共二十八篇文章，內容多為文化現象和樂評，範圍小至心理層面，大至社會現象，不難從中發現學生觀點的多元性，閱讀完本期後更可發現大眾所不知道的社會脈絡。
法界流氓　定義新「正義」
(2013-10-06)
李盈如
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Department of Communication and Technology
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傳播與科技學系
正義是什麼？真相又何在？人們的生活中無時無刻都由法律來控制行為，《王牌大律師》以詼諧的法庭攻防戰帶觀眾一步步逼近問題核心，重新定義心中的「正義」。
不「紙」是膠帶
(2013-10-06)
江岱燕
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Department of Communication and Technology
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傳播與科技學系
從純色基本款到條紋進階款，或是結合時令節慶而特地設計的限定版，紙膠帶的定義已不單是「用紙製成，可重覆黏貼的膠帶」。時下流行的紙膠帶是充滿各種風格與花色，可應用在裝飾手帳、製作卡片的萬用小工具。
言論自由　捍衛圖書館
(2013-10-06)
林燕婷
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Department of Communication and Technology
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傳播與科技學系
由小說改編而來，於九月十三日上映的《圖書館戰爭》，在一個架空的年代，為我們訴說著高層管制閱覽自由，控制人民思想，一群挺身捍衛圖書的人們，充滿熱血的故事。
歌武青春　復刻戀情
(2013-10-06)
陳佩瑄
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Department of Communication and Technology
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傳播與科技學系
睽違六年，亞洲天王周杰倫，二度自導自演電影《天台》，是構思整整六年後的第二部正宗周杰倫電影。《天台》這部片以復古為基礎，融合歌唱、舞蹈以及武術三元素，是台灣首部「歌武片」，令人耳目一新。
詐騙新型態　小酌妹兵團
(2013-10-06)
林妍君
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Department of Communication and Technology
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傳播與科技學系
大安區的高檔餐廳裡，一名男子將剛剛點的昂貴紅酒啜入口中，身邊的女網友今天第一次見面，餐廳裡昏黃的燈光讓她臉上更顯嬌媚可愛，男子心想，即使這裡消費高昂，但今天能有佳人相伴，也算值得了。