Browsing by Issue Date, starting with "2018-06-20"

Now showing 1 - 20 of 10441

Programmable Synaptic Metaplasticity and below Femtojoule Spiking Energy Realized in Graphene-Based Neuromorphic Memristor
(2018-06-20)
Liu, Bo
;
Liu, Zhiwei
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Chiu, In-Shiang
;
Di, MengFu
;
Wu, YongRen
Memristors with rich interior dynamics of ion migration are promising for mimicking various biological synaptic functions in neuromorphic hardware systems. A graphene-based memristor shows an extremely low energy consumption of less than a femtojoule per spike, by taking advantage of weak surface van der Waals interaction of graphene. The device also shows an intriguing programmable metaplasticity property in which the synaptic plasticity depends on the history of the stimuli and yet allows rapid reconfiguration via an immediate stimulus. This graphene-based memristor could be a promising building block toward designing highly versatile and extremely energy efficient neuromorphic computing systems.
Transient AID expression for in situ mutagenesis with improved cellular fitness
(2018-06-20)
Al-Qaisi, Talal Salem
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Su, Yu-Cheng
;
Roffler, Steve R.
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生物科技學系
;
Department of Biological Science and Technology
Activation induced cytidine deaminase (AID) in germinal center B cells introduces somatic DNA mutations in transcribed immunoglobulin genes to increase antibody diversity. Ectopic expression of AID coupled with selection has been successfully employed to develop proteins with desirable properties. However, this process is laborious and time consuming because many rounds of selection are typically required to isolate the target proteins. AID expression can also adversely affect cell viability due to off target mutagenesis. Here we compared stable and transient expression of AID mutants with different catalytic activities to determine conditions for maximum accumulation of mutations with minimal toxicity. We find that transient (3-5 days) expression of an AID upmutant in the presence of selection pressure could induce a high rate of mutagenesis in reporter genes without affecting cells growth and expansion. Our findings may help improve protein evolution by ectopic expression of AID and other enzymes that can induce DNA mutations.
Liquid-Crystal Active Tamm-Plasmon Devices
(2018-06-20)
Cheng, Hao-Chi
;
Kuo, Ching-Yung
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Hung, Yu-Ju
;
Chen, Kuo-Ping
;
Jeng, Shie-Chang
We demonstrate a liquid-crystal (LC)-tuned Tamm-plasmon (TP) resonance device. The term TP polariton refers to plasmonic resonance at the interface between a photonic crystal (PC) and a metallic film. We formulate a precise optical analysis of the proposed device using the transfer-matrix method. A single resonance dip in the photonic band-gap region guarantees that the thickness of the LC layer between the PC and the metallic film can be as small as about 180 nm. Tuning phase retardation in the LC layer is shown to shift the resonance wavelength tens of nanometers, depending on the birefringence and width of the LC layer. Simulation results are in good agreement with the experimental data.
交大e-News第257期-交大、中國醫大攜手於腫瘤免疫療法有重大突破
(2018-06-20)
國立交通大學秘書室
;
Secretariat
Double thermoelectric power factor of a 2D electron system
(2018-06-20)
Zhang, Yuqiao
;
Feng, Bin
;
Hayashi, Hiroyuki
;
Chang, Cheng-Ping
;
Sheu, Yu-Miin
Two-dimensional electron systems have attracted attention as thermoelectric materials, which can directly convert waste heat into electricity. It has been theoretically predicted that thermoelectric power factor can be largely enhanced when the two-dimensional electron layer is far narrower than the de Broglie wavelength. Although many studies have been made, the effectiveness has not been experimentally clarified thus far. Here we experimentally clarify that an enhanced two-dimensionality is efficient to enhance thermoelectric power factor. We fabricated superlattices of [N unit cell SrTi1-xNbxO3 vertical bar 11 unit cell SrTiO3](10)-there are two different de Broglie wavelength in the SrTi1-xNbxO3 system. The maximum power factor of the superlattice composed of the longer de Broglie wavelength SrTi1-xNbxO3 exceeded similar to 5 mWm(-1) K-2, which doubles the value of optimized bulk SrTi1- xNbxO3. The present approach-use of longer de Broglie wavelength-is epoch-making and is fruitful to design good thermoelectric materials showing high power factor.
Halbleitervorrichtung und Verfahren zur Herstellung derselben
(2018-06-21)
CHANG EDWARD YI
;
LIU SHIH-CHIEN
;
HUANG CHUNG-KAI
;
WU CHIA-HSUN
;
HAN PING-CHENG
A semiconductor device includes a substrate, a channel layer, a barrier layer, a recess, a charge trapping layer, a ferroelectric material layer, a gate, a source and a drain. The channel layer is disposed on the substrate. The barrier layer is disposed on the channel layer. The barrier layer has a recess, and a portion of the barrier layer under the recess has a thickness. The source and the drain are disposed on the barrier layer. The charge trapping layer covers the bottom of the recess. The ferroelectric material is disposed on the charge trapping layer. The gate is disposed on the ferroelectric material.
NONINVASIVE STEREOTACTIC ASSEMBLY
(2018-06-21)
Bing-Shiang Yang
;
Yu-Hsiang Hao
A noninvasive stereotactic assembly for guiding an instrument to a target within a patient's head includes a head frame subassembly and an instrument positioning subassembly. The head frame subassembly is secured to a skull in the patient's head to determine an X-axis and a Y-axis of a three-dimensional coordinate system. According to the coordinate of the target in the three-dimensional coordinate system, ring members, a movable bracket, a swivel member, and an instrument holder of the instrument positioning subassembly are displaced by predetermined angles to guide the instrument toward the target.
半導体装置及びその製造方法
(2018-06-21)
張翼
;
劉世謙
;
▲黄▼ 崇▲カイ▼
;
▲呉▼ 佳勳
;
韓秉承
【課題】閾値を６Ｖよりも大きくし、誤起動の発生を効果的に避ける半導体装置及びその製造方法を提供する。【解決手段】半導体装置は、基材１１０と、チャネル層１２０と、バリア層１３０と、溝と、電荷トラップ層２２０と、強誘電体材料２３０と、ゲート２５０と、ソースＳと、ドレインＤと、を含む。チャネル層１２０は、基材１１０に配置される。バリア層１３０は、チャネル層１２０に配置される。バリア層１３０は溝を有し、且つ、溝の下方のバリア層１３０は、厚さを有する。ドレインＤとソースＳは、バリア層１３０に配置される。電荷トラップ層２２０は、溝の底面を覆う。強誘電体材料２３０は、電荷トラップ層２２０に配置される。ゲート２５０は、強誘電体材料２３０に設けられる。【選択図】図４Ａ
SEMICONDUCTOR DEVICE AND METHOD OF MANUFACTURING THE SAME
(2018-06-21)
Edward Yi CHANG
;
Shih-Chien LIU
;
Chung-Kai HUANG
;
Chia-Hsun WU
;
Ping-Cheng HAN
A semiconductor device includes a substrate, a channel layer, a barrier layer, a recess, a charge trapping layer, a ferroelectric material layer, a gate, a source and a drain. The channel layer is disposed on the substrate. The barrier layer is disposed on the channel layer. The barrier layer has a recess, and a portion of the barrier layer under the recess has a thickness. The source and the drain are disposed on the barrier layer. The charge trapping layer covers the bottom of the recess. The ferroelectric material is disposed on the charge trapping layer. The gate is disposed on the ferroelectric material.
Development of oxide heteroepitaxy for soft technology
(2018-06-21)
Wu, Ping-Chun
;
Chu, Ying-Hao
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材料科學與工程學系
;
電子物理學系
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Department of Materials Science and Engineering
Soft technology has been an emerging field since flexible and wearable electronics started flourishing. In this research field, oxides can play an important role due to their intriguing functionalities and superior thermal and chemical stabilities. To deliver high-quality thin films or structures based on oxides, heteroepitaxy is essential. However, the lack of a suitable approach remains an obstacle for flexible oxide heteroepitaxy. Recently, due to the advancement of growth facilities and characterization tools, various techniques have been employed to acquire flexible oxide heteroepitaxy. This review highlights the methods as well as direct and indirect approaches that are essential for developing oxide heteroepitaxy with mechanical flexibility. We also provide an overview, classifying the fields in terms of applications involving flexible oxide heteroepitaxy and the development of oxide-based approaches.
Recurrent symbiont recruitment from fungal parasites in cicadas
(2018-06-26)
Matsuura, Yu
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Moriyama, Minoru
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Lukasik, Piotr
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Vanderpool, Dan
;
Tanahashi, Masahiko
Diverse insects are associated with ancient bacterial symbionts, whose genomes have often suffered drastic reduction and degeneration. In extreme cases, such symbiont genomes seem almost unable to sustain the basic cellular functioning, which comprises an open question in the evolution of symbiosis. Here, we report an insect group wherein an ancient symbiont lineage suffering massive genome erosion has experienced recurrent extinction and replacement by host-associated pathogenic microbes. Cicadas are associated with the ancient bacterial co-obligate symbionts Sulcia and Hodgkinia, whose streamlined genomes are specialized for synthesizing essential amino acids, thereby enabling the host to live on plant sap. However, our inspection of 24 Japanese cicada species revealed that while all species possessed Sulcia, only nine species retained Hodgkinia, and their genomes exhibited substantial structural instability. The remaining 15 species lacked Hodgkinia and instead harbored yeastlike fungal symbionts. Detailed phylogenetic analyses uncovered repeated Hodgkinia-fungus and fungus-fungus replacements in cicadas. The fungal symbionts were phylogenetically intermingled with cicada-parasitizing Ophiocordyceps fungi, identifying entomopathogenic origins of the fungal symbionts. Most fungal symbionts of cicadas were uncultivable, but the fungal symbiont of Meimuna opalifera was cultivable, possibly because it is at an early stage of fungal symbiont replacement. Genome sequencing of the fungal symbiont revealed its metabolic versatility, presumably capable of synthesizing almost all amino acids, vitamins, and other metabolites, which is more than sufficient to compensate for the Hodgkinia loss. These findings highlight a straightforward ecological and evolutionary connection between parasitism and symbiosis, which may provide an evolutionary trajectory to renovate deteriorated ancient symbiosis via pathogen domestication.
Hierarchical Polymer Structures Using Templates and the Modified Breath Figure Method
(2018-06-26)
Lee, Lin-Ruei
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Liu, Chih-Ting
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Tseng, Hsiao-Fan
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Lin, Kuan-Ting
;
Chu, Chien-Wei
Hierarchical structures are commonly observed in nature and possess unique properties. The fabrication of hierarchical structures with well-controlled sizes in different length scales, however, is still a great challenge. To further understand the morphologies and properties of the hierarchical structures, here we present a novel strategy to prepare hierarchical polymer structures by combining the modified breath figure method and the template method. Poly(methyl methacrylate) (PMMA) honeycomb films with regular micropores are first prepared using the modified breath figure method by dipping PMMA films into mixtures of chloroform and methanol. The polymer chains on the honeycomb films are then annealed and wetted into the nanopores of anodic aluminum oxide templates via capillary forces, resulting in the formation of hierarchical polymer structures. The morphologies of the polymer structures, which can be controlled by the molecular weights of the polymers and the concentrations of the polymer solutions, are characterized by scanning electron microscopy. The surface wettabilities of the polymer structures are also examined by water contact angle measurements, and the hierarchical structures are observed to be more hydrophobic than the flat films and honeycomb films. This work not only provides a feasible approach to fabricate hierarchical polymer structures with controlled sizes but also gives a better understanding of the relationship between surface morphologies and properties.
Cross-linked Triarylamine-Based Hole-Transporting Layer for Solution-Processed PEDOT:PSS-Free Inverted Perovskite Solar Cells
(2018-06-27)
Chang, Chia-Chih
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Tao, Jhih-Hao
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Tsai, Che-En
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Cheng, Yen-Ju
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Hsu, Chain-Shu
The device performance of inverted organic metallohalide perovskite solar cells (OMPSCs) is optimized via tailoring the electrode surfaces with electron- and hole-transporting materials. This work demonstrates the fabrication of PEDOT:PSS-free OMPSCs using' a hole-transporting composite material consisting of bilayered vanadium oxide (VOx) and a thermally cross-linked triarylamine-based material X-DVTPD, which contributes to higher V-oc and J(sc) values. The hydrophobicity of X-DVTPD resulted in the formation of large perovskite crystals and enhanced the stability of OMPSCs. Integration of ionic fullerene derivative, fulleropyrrolidinium iodide, in OMPSCs as a hole-blocking interfacial layer at the interface with Ag proves effective to further boost the device efficiency to 18.08%.
Femtosecond Laser Trapping Dynamics of Nanoparticles: A Single Transient Assembly Formation Leading to Their Directional Ejection
(2018-06-28)
Chiang, Wei-Yi
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Usrnan, Anwar
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Sugiyama, Teruki
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Hofkens, Johan
;
Masuhara, Hiroshi
We investigated femtosecond laser trapping dynamics of silica nanoparticles with different hydrophobic surface properties. We demonstrated that the hydrophobic surface on the silica nanoparticles facilitates mutual association of the nanoparticles in the optical trapping site. Such association of optically trapped nanoparticles is a prerequisite to induce their directional ejection away from the trapping site. The directional ejection of the optically trapped nanoparticles is most probably due to asymmetric three-dimensional ejecting forces generated by the electromagnetic interaction between transient assembly in the focal spot and the incident pulses. These findings provide important insights into the directional ejection of nanoparticles from the trapping site in the femtosecond laser trapping, and this physicochemical phenomenon is controlled by both the trapping laser and material properties.
Anisotropic power-law inflation of the five dimensional scalar-vector and scalar-Kalb-Ramond model
(2018-06-28)
Do, Tuan Q.
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Kao, W. F.
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物理研究所
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Institute of Physics
We will study the cosmological implications of the five dimensional scalar-vector and scalar-Kalb-Ramond model. In particular, a new set of Bianchi type I power-law analytic solution will be obtained for this model. The cosmic no-hair conjecture can be shown to break down in the presence of the scalar-vector and scalar-Kalb-Ramond couplings. The effect of the Kalb-Ramond field in the presence of the power-law solution will be shown explicitly. We will also show that the presence of a phantom field does, however, destabilize the corresponding Bianchi type I power-law inflationary solutions.
Plasmon-Assisted Polarity Switching of a Photoelectric Conversion Device by UV and Visible Light Irradiation
(2018-06-28)
Nakamura, Keisuke
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Oshikiri, Tomoya
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Ueno, Kosei
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Katase, Takayoshi
;
Ohta, Hiromichi
The plasmon-induced charge separation between metallic nanoparticles and a semiconductor following an electron transfer process has been extensively studied as one of the mechanisms in plasmonic light energy conversion devices. In this study, we propose that the switching of photocurrent polarity can be realized by changing the rectification properties of plasmonic photoelectric conversion devices and utilizing the difference in carrier mobility between electrons and holes. We fabricated plasmonic photoelectric conversion devices using gold nanoparticles (Au-NPs), nickel oxide (NiO), and mobility-limited TiO2 (ML-TiO2) to control the photocurrent polarity according to irradiation wavelengths of visible and UV light. A pulsed laser deposition technique was employed to deposit the ML-TiO2 and NiO layers. The photoelectric properties were measured, and in situ spectroelectrochemical measurements were performed to investigate the relationship between the rectification properties of the plasmonic photoelectric conversion devices and the change in the Fermi level of the Au-NPs under UV light irradiation condition. Additionally, UV and visible light irradiation selectively induced the current of opposite polarity with the small applied voltage. The electron transfer phenomena from ML-TiO2 to Au-NPs and from Au-NPs to ML-TiO2 give us important information to understand plasmon-related charge separation.
Correction of center of rotation and projection angle in synchrotron X-ray computed tomography
(2018-06-29)
Cheng, Chang-Chieh
;
Ching, Yu-Tai
;
Ko, Pai-Hung
;
Hwu, Yeukuang
;
資訊工程學系
An error in tomographic reconstruction parameters can result considerable artifacts in the reconstructed image, particularly in micro-computed tomography and nano-computed tomography. This study involved designing an automatic method for efficiently correcting errors resulting from incorrectly determined rotational axes and projection angles. In this method, errors are corrected by minimizing the "total variation" of a reconstructed image, and minimization is accomplished by using the gradient descent method. Compared with two previous methods, the proposed method achieved the best reconstruction results.
【醫療器材法規與實務講座】系列十一
(國立陽明大學, 2018-06-29)
陽明電子報編輯小組
美國為全球醫療器材主要市場之一，亦為台灣主要輸入與輸出區域，醫療器材產品相關管理規範成熟，一直為台灣醫材業者所關注。醫療器材著重產品的安全性與有效性，因此從產品設計開發、製造、測試、臨床試驗、銷售等，皆受美國TFDA監管。
熱血陽明，今夏捐血破紀錄
(國立陽明大學, 2018-06-29)
陽明電子報編輯小組
本學期第二次捐血活動，在衛保組大力宣傳下，許多師生熱烈反應，6月6、7日兩天共有308人捐血，共募得349袋熱血，創下歷年來最佳紀錄。衛保組表示，本次捐血活動獲得校友總會、校友中心以及國際獅子會的熱心贊助，推出捐血成功獎、早鳥獎、首捐獎等將近500份獎品，鼓勵大家踴躍捐血，特別是未曾捐過血的師生勇於嘗試，以擴增血源，結果獲得308人響應，其中258人捐血成功，91人更捐血500c.c.。
「校長盃」羽球賽，人社院首度奪冠
(國立陽明大學, 2018-06-29)
陽明電子報編輯小組
每到學年結束，就是「校長盃」教職員工羽球聯誼賽登場的時候。今年比賽在 6月20、21兩日熱鬧開打，共有各單位、系所約70位羽球愛好者一起切磋球技。比賽結果，由高手雲集的人社院首度奪冠。實力相當的研發處、物輔系、學務B三隊積分相同，最後根據點數分列亞軍、季軍、殿軍。首度參加「校長盃」羽球聯誼賽的郭校長，在開幕式勉勵大家說，振興體育是學校目前的重要工作之一，不管是軟硬體、教職員或學生，或者競賽型、休閒型，都希望能做得更好，謝謝體育室的籌辦和大家的參與；也希望透過兩天的聯誼賽，大家能夠聯誼、交朋友、獲得運動的樂趣，進一步提昇學校羽球的水準。