bluuebunny/crossref_metadata_2025_split huggingface dataset:
Wearable red–green–blue quantum dot light-emitting diode array using high-resolution intaglio transfer printing
Authors: Choi Moon Kee , Yang Jiwoong , Kang Kwanghun , Kim Dong Chan , Choi Changsoon , Park Chaneui , Kim Seok Joo , Chae Sue In , Kim Tae-Ho , Kim Ji Hoon , Hyeon Taeghwan , Kim Dae-Hyeong 
Published: May 2015

AbstractDeformable full-colour light-emitting diodes with ultrafine pixels are essential for wearable electronics, which requires the conformal integration on curvilinear surface as well as retina-like high-definition displays. However, there are remaining challenges in terms of polychromatic configuration, electroluminescence efficiency and/or multidirectional deformability. Here we present ultra-thin, wearable colloidal quantum dot light-emitting diode arrays utilizing the intaglio transfer printing technique, which allows the alignment of red–green–blue pixels with high resolutions up to 2,460 pixels per inch. This technique is readily scalable and adaptable for low-voltage-driven pixelated white quantum dot light-emitting diodes and electronic tattoos, showing the best electroluminescence performance (14,000 cd m−2 at 7 V) among the wearable light-emitting diodes reported up to date. The device performance is stable on flat, curved and convoluted surfaces under mechanical deformations such as bending, crumpling and wrinkling. These deformable device arrays highlight new possibilities for integrating high-definition full-colour displays in wearable electronics.
Role of the Tau N-terminal region in microtubule stabilization revealed by newendogenous truncated forms
Authors: Derisbourg Maxime , Leghay Coline , Chiappetta Giovanni , Fernandez-Gomez Francisco-Jose , Laurent Cyril , Demeyer Dominique , Carrier Sébastien , Buée-Scherrer Valérie , Blum David , Vinh Joëlle , Sergeant Nicolas , Verdier Yann , Buée Luc , Hamdane Malika 
Published: May 2015

AbstractTau is a central player in Alzheimer's disease (AD) and relatedTauopathies, where it is found as aggregates in degenerating neurons. Abnormalpost-translational modifications, such as truncation, are likely involved in thepathological process. A major step forward in understanding the role of Tautruncation would be to identify the precise cleavage sites of the several truncatedTau fragments that are observed until now in AD brains, especially those truncatedat the N-terminus, which are less characterized than those truncated at theC-terminus. Here, we optimized a proteomics approach and succeeded in identifying anumber of new N-terminally truncated Tau species from the human brain. We initiatedcell-based functional studies by analyzing the biochemical characteristics of twoN-terminally truncated Tau species starting at residues Met11 and Gln124respectively. Our results show, interestingly, that the Gln124-Tau fragment displaysa stronger ability to bind and stabilize microtubules, suggesting that the TauN-terminal domain could play a direct role in the regulation of microtubulestabilization. Future studies based on our new N-terminally truncated-Tau speciesshould improve our knowledge of the role of truncation in Tau biology as well as inthe AD pathological process.
Optogenetic stimulation of mPFC pyramidal neurons as a conditioned stimulus supports associative learning in rats
Authors: Wu Guang-yan , Liu Guo-long , Zhang Hui-min , Chen Chong , Liu Shu-lei , Feng Hua , Sui Jian-feng 
Published: May 2015

AbstractIt is generally accepted that the associative learning occurs when a behaviorally neutral conditioned stimulus (CS) is paired with an aversive unconditioned stimulus (US) in close temporal proximity. Eyeblink conditioning (EBC) is a simple form of associative learning for motor responses. Specific activation of a population of cells may be an effective and sufficient CS for establishing EBC. However, there has been no direct evidence to support this hypothesis. Here, we show in rats that optogenetic activation of the right caudal mPFC pyramidal neurons as a CS is sufficient to support the acquisition of delay eyeblink conditioning (DEC). Interestingly, the associative memory was not stably expressed during the initial period of daily conditioning session even after the CR acquisition reached the asymptotic level. Finally, the intensity and consistency of the CS were found to be crucial factors in regulating the retrieval of the associative memory. These results may be of importance in understanding the neural cellular mechanisms underlying associative learning and the mechanisms underlying retrieval process of memory.
Trichostatin A specifically improves the aberrant expression of transcription factor genes in embryos produced by somatic cell nuclear transfer
Authors: Inoue Kimiko , Oikawa Mami , Kamimura Satoshi , Ogonuki Narumi , Nakamura Toshinobu , Nakano Toru , Abe Kuniya , Ogura Atsuo 
Published: May 2015

AbstractAlthough mammalian cloning by somatic cell nuclear transfer (SCNT) has been established in various species, the low developmental efficiency has hampered its practical applications. Treatment of SCNT-derived embryos with histone deacetylase (HDAC) inhibitors can improve their development, but the underlying mechanism is still unclear. To address this question, we analysed gene expression profiles of SCNT-derived 2-cell mouse embryos treated with trichostatin A (TSA), a potent HDAC inhibitor that is best used for mouse cloning. Unexpectedly, TSA had no effect on the numbers of aberrantly expressed genes or the overall gene expression pattern in the embryos. However, in-depth investigation by gene ontology and functional analyses revealed that TSA treatment specifically improved the expression of a small subset of genes encoding transcription factors and their regulatory factors, suggesting their positive involvement in de novo RNA synthesis. Indeed, introduction of one of such transcription factors, Spi-C, into the embryos at least partially mimicked the TSA-induced improvement in embryonic development by activating gene networks associated with transcriptional regulation. Thus, the effects of TSA treatment on embryonic gene expression did not seem to be stochastic, but more specific than expected, targeting genes that direct development and trigger zygotic genome activation at the 2-cell stage.
Metrology of confined flows using wide field nanoparticle velocimetry
Authors: Ranchon Hubert , Picot Vincent , Bancaud Aurélien 
Published: May 2015

AbstractThe manipulation of fluids in micro/nanofabricated systems opens new avenues to engineer the transport of matter at the molecular level. Yet the number of methods for thein situcharacterization of fluid flows in shallow channels is limited. Here we establish a simple method called nanoparticle velocimetry distribution analysis (NVDA) that relies on wide field microscopy to measure the flow rate and channel height based on the fitting of particle velocity distributions along and across the flow direction. NVDA is validated by simulations, showing errors in velocity and height determination of less than 1% and 8% respectively, as well as with experiments, in which we monitor the behavior of 200 nm nanoparticles conveyed in channels of ~1.8 μm in height. We then show the relevance of this assay for the characterization of flows in bulging channels and prove its suitability to characterize the concentration of particles across the channel height in the context of visco-elastic focusing. Our method for rapid and quantitative flow characterization has therefore a broad spectrum of applications in micro/nanofluidics and a strong potential for the optimization of Lab-on-Chips modules in which engineering of confined transport is necessary.
Extraordinary Capability for Water Treatment Achieved by a Perfluorous Conjugated Microporous Polymer
Authors: Yang Rui-Xia , Wang Ting-Ting , Deng Wei-Qiao 
Published: May 2015

AbstractOils, organic solvents, dyes and heavy metal ions are primary pollutants in water resources. Currently, no sorbent material can effectively remove these types of pollutants simultaneously. Here we report a perfluorous conjugated microporous polymer with superhydrophobicity and a large surface area, which exhibits outstanding adsorption capacities, kinetics and recyclability for a wide range of organic solvents, oils, dyes and heavy metal ions. The adsorption capacities of this polymer, 1376.7 mg g−1 for Congo red, 808.2 mg g−1 for Pb(II) and 303.2 mg g−1 for As(V), are higher than the adsorption capacities of any previously described porous materials. Our theoretical calculation reveals that the superior properties of this polymer are due to fluorination and triple bonds within the polymer. A benchmark experiment indicates that this polymer can efficiently remove these pollutants simultaneously. Application of this polymer may lead to the development of next-generation reusable and portable water purification appliances.
Silver (I) as DNA glue: Ag+-mediated guanine pairing revealed by removing Watson-Crick constraints
Authors: Swasey Steven M. , Leal Leonardo Espinosa , Lopez-Acevedo Olga , Pavlovich James , Gwinn Elisabeth G. 
Published: May 2015

AbstractMetal ion interactions with DNA have far-reaching implications in biochemistry and DNA nanotechnology. Ag+ is uniquely interesting because it binds exclusively to the bases rather than the backbone of DNA, without the toxicity of Hg2+. In contrast to prior studies of Ag+ incorporation into double-stranded DNA, we remove the constraints of Watson-Crick pairing by focusing on homo-base DNA oligomers of the canonical bases. High resolution electro-spray ionization mass spectrometry reveals an unanticipated Ag+-mediated pairing of guanine homo-base strands, with higher stability than canonical guanine-cytosine pairing. By exploring unrestricted binding geometries, quantum chemical calculations find that Ag+ bridges between non-canonical sites on guanine bases. Circular dichroism spectroscopy shows that the Ag+-mediated structuring of guanine homobase strands persists to at least 90 °C under conditions for which canonical guanine-cytosine duplexes melt below 20 °C. These findings are promising for DNA nanotechnology and metal-ion based biomedical science.
Soft X-Ray Microscopy Radiation Damage On Fixed Cells Investigated With Synchrotron Radiation FTIR Microscopy
Authors: Gianoncelli A. , Vaccari L. , Kourousias G. , Cassese D. , Bedolla D. E. , Kenig S. , Storici P. , Lazzarino M. , Kiskinova M. 
Published: May 2015

AbstractRadiation damage of biological samples remains a limiting factor in high resolution X-ray microscopy (XRM). Several studies have attempted to evaluate the extent and the effects of radiation damage, proposing strategies to minimise or prevent it. The present work aims to assess the impact of soft X-rays on formalin fixed cells on a systematic manner. The novelty of this approach resides on investigating the radiation damage not only with XRM, as often reported in relevant literature on the topic, but by coupling it with two additional independent non-destructive microscopy methods: Atomic Force Microscopy (AFM) and FTIR Microscopy (FTIRM). Human Embryonic Kidney 293 cells were exposed to different radiation doses at 1 keV. In order to reveal possible morphological and biochemical changes, the irradiated cells were systematically analysed with AFM and FTIRM before and after. Results reveal that while cell morphology is not substantially affected, cellular biochemical profile changes significantly and progressively when increasing dose, resulting in a severe breakdown of the covalent bonding network. This information impacts most soft XRM studies on fixed cells and adds an in-depth understanding of the radiation damage for developing better prevention strategies.
On the superposition principle in interference experiments
Authors: Sinha Aninda , H. Vijay Aravind , Sinha Urbasi 
Published: May 2015

AbstractThe superposition principle is usually incorrectly applied in interference experiments. This has recently been investigated through numerics based on Finite Difference Time Domain (FDTD) methods as well as the Feynman path integral formalism. In the current work, we have derived an analytic formula for the Sorkin parameter which can be used to determine the deviation from the application of the principle. We have found excellent agreement between the analytic distribution and those that have been earlier estimated by numerical integration as well as resource intensive FDTD simulations. The analytic handle would be useful for comparing theory with future experiments. It is applicable both to physics based on classical wave equations as well as the non-relativistic Schrödinger equation.
Magnetic Transition to Antiferromagnetic Phase in Gadolinium Substituted Topological Insulator Bi2Te3
Authors: Kim Jinsu , Lee Kyujoon , Takabatake Toshiro , Kim Hanchul , Kim Miyoung , Jung Myung-Hwa 
Published: May 2015

AbstractThere are many interests to achieve long-range magnetic order in topological insulators of Bi2Se3 or Bi2Te3 by doping magnetic transition metals such as Fe and Mn. The transition metals act as not only magnetic dopants but also electric dopants because they are usually divalent. However, if the doping elements are rare-earth metals such as Gd, which are trivalent, only magnetic moments can be introduced. We fabricated single crystals of Bi2-xGdxTe3 (0 ≤ × ≤ 0.2), in which we observed magnetic phase change from paramagnetic (PM) to antiferromagnetic (AFM) phase by increasing x. This PM-to-AFM phase transition agrees with the density functional theory calculations showing a weak and short-ranged Gd-Gd AFM coupling via the intervening Te ions. The critical point corresponding to the magnetic phase transition is x = 0.09, where large linear magnetoresistance and highly anisotropic Shubnikov-de Haas oscillations are observed. These results are discussed with two-dimensional properties of topological surface state electrons.
Marine lipopeptide Iturin A inhibits Akt mediated GSK3β and FoxO3a signaling and triggers apoptosis in breast cancer
Authors: Dey Goutam , Bharti Rashmi , Dhanarajan Gunaseelan , Das Subhasis , Dey Kaushik Kumar , Kumar B N Prashanth , Sen Ramkrishna , Mandal Mahitosh 
Published: May 2015

AbstractAkt kinase is a critical component of the PI3K/Akt signaling pathway, which is frequently over expressed in human cancers including breast. Therapeutic regimens for inhibiting breast cancer with aberrant Akt activity are essential. Here, we evaluated antitumor effect of a marine bacteria derived lipopeptide ‘Iturin A’ on human breast cancer in vitro and in vivo through disrupting Akt pathway. Proliferation of MDA-MB-231 and MCF-7 breast cancer cells were significantly inhibited by Iturin A and it induced apoptosis as confirmed by increased Sub G1 populations, DNA fragmentation, morphological changes and western blot analysis. Furthermore, Iturin A inhibited EGF induced Akt phosphorylation (Ser473 and Thr308) and its downstream targets GSK3β and FoxO3a. Iturin A inactivated MAPK as well as Akt kinase leading to the translocation of FoxO3a to the nucleus. Gene silencing of Akt in MDA-MB-231 and MCF-7 cells reduced the sensitivity of cancer cells to Iturin A. Interestingly, overexpression of Akt with Akt plasmid in cancer cells caused highly susceptible to induce apoptosis by Iturin A treatment. In a xenograft model, Iturin A inhibited tumor growth with reduced expressions of Ki-67, CD-31, P-Akt, P-GSK3β, P-FoxO3a and P-MAPK. Collectively, these findings imply that Iturin A has potential anticancer effect on breast cancer.
Elemental bioimaging of Cisplatin in Caenorhabditis elegans by LA-ICP-MS
Authors: Crone Barbara , Aschner Michael , Schwerdtle Tanja , Karst Uwe , Bornhorst Julia 
Published: May 2015

Abstract
cis-Diamminedichloroplatinum(ii) (Cisplatin) is one of the most important and frequently used cytostatic drugs for the treatment of various solid tumors. Herein, a laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) method incorporating a fast and simple sample preparation protocol was developed for the elemental mapping of Cisplatin in the model organism Caenorhabditis elegans (C. elegans). The method allows imaging of the spatially-resolved elemental distribution of platinum in the whole organism with respect to the anatomic structure in L4 stage worms at a lateral resolution of 5 μm. In addition, a dose- and time-dependent Cisplatin uptake was corroborated quantitatively by a total reflection X-ray fluorescence spectroscopy (TXRF) method, and the elemental mapping indicated that Cisplatin is located in the intestine and in the head of the worms. Better understanding of the distribution of Cisplatin in this well-established model organism will be instrumental in deciphering Cisplatin toxicity and pharmacokinetics. Since the cytostatic effect of Cisplatin is based on binding the DNA by forming intra- and interstrand crosslinks, the response of poly(ADP-ribose)metabolism enzyme 1 (pme-1) deletion mutants to Cisplatin was also examined. Loss of pme-1, which is the C. elegans ortholog of human poly(ADP-ribose) polymerase 1 (PARP-1) led to disturbed DNA damage response. With respect to survival and brood size, pme-1 deletion mutants were more sensitive to Cisplatin as compared to wildtype worms, while Cisplatin uptake was indistinguishable.
Design of wideband absorbers using RLC screen
Authors: Kim Gunyoung , Lee Bomson 
Published: May 2015

Design equations for wideband single‐layer absorbers based on the condition of zero slope reactance (or susceptance) at a specific centre frequency are presented. Using the design equations, a microwave absorber is realised employing a cross‐shaped strip structure as a unit on an FR‐4 substrate with a relative permittivity of 4.6 and height of 3.2 mm. At a design centre frequency of 10.93 GHz, the size of each unit is 9.6 × 9.6 × 3.2 mm and the overall size of the fabricated absorber is 336 × 336 × 3.2 mm. The EM‐simulated and measured absorptions are close to 100% at the design centre frequency and their 90% bandwidths are about 47% (the limit for the case of the layer with εr = 4.6). The absorption characteristics of the proposed absorber are shown to be almost unaffected by the polarisation angles of normally incident TEM waves.
Front‐to‐back ratio improvement of printed antennas based on electrically small resonators for microwave presence detectors
Authors: Aguilà P. , Zuffanelli S. , Zamora G. , Paredes F. , Martín F. , Bonache J. 
Published: May 2015

The improvement of the front‐to‐back ratio (FBR) in low‐profile antennas to be used in presence detection devices is explored. The main idea is to use electrically small resonators as radiating elements. This minimises the electric currents in the boundary of the ground plane at the working frequency, thus reducing the backward radiation. The choice of the resonant particle and its electromagnetic properties, along with the antenna structure, are discussed. The simulated results indicate that there is good impedance matching (−18 dB) at the operating frequency (3 GHz) and an excellent FBR of 24 dB. These characteristics are validated experimentally and the FBR is compared with that of a conventional patch antenna.
Dual‐broadband dielectric resonator antenna based on modified Sierpinski fractal geometry
Authors: Liu Hu , Liu Ying , Wei Ming , Gong Shuxi 
Published: May 2015

A novel dual‐broadband dielectric resonator antenna (DRA) is presented. The proposed antenna has realised both dual‐band and wideband features by applying the modified Sierpinski structure to the antenna design of the proposed DRA. The measured impedance bandwidths for │S11│ < −10 dB are 2.25–2.6 GHz (14.46%) and 3.1–4.1 GHz (27.78%), which can cover the wireless local area network (WLAN, 2.4–2.484 GHz) and the worldwide interoperability for microwave access (WiMAX, 3.4–3.69 GHz) bands. Meanwhile, stable radiation patterns and gains of about 5 and 3.8 dBi at 2.4 and 3.5 GHz, respectively, have been observed.
Implementation of a new medium voltage asymmetric pulse‐width modulation converter with balanced input capacitor voltages
Authors: Lin Bor‐Ren , Zhang Sheng‐Zhi 
Published: May 2015

A 1.44 kW DC/DC converter with zero voltage switching (ZVS) for medium voltage applications is proposed in this study. Two half‐bridge circuits with split capacitors are connected in series at high voltage side to limit voltage stresses of power switches at Vin/2. Three DC/DC circuits are adopted to share load current and reduce the current stress of rectifier diodes, transformers and output filter inductors. Two balance capacitors are used in the proposed circuit to automatically balance input split capacitor voltages in every switching cycle. The current doubler rectifier is adopted at low voltage side to partially cancel ripple current so that the root‐mean‐square current at output capacitor is reduced. Asymmetric pulse‐width modulation is used to adjust the duty cycle of power switches and regulate output voltage. The output capacitance of power switches and the external resonant inductance are resonant at the transition interval and power metal‐oxide‐semiconductor field‐effect transistors can be turned on under ZVS. The proposed converter can be applied for high input voltage applications such as a three‐phase 380 V/480 V utility system. Experimental results from a 750–800 V input and 24 V/60 A output are provided to demonstrate the performance of proposed converter.
A natural experiment of the consequences of concentrating former prisoners in the same neighborhoods
Authors: Kirk David S. 
Published: May 2015

Significance
There are ∼5 million formerly imprisoned individuals residing in US neighborhoods, yet this population is highly concentrated in a relatively small number of neighborhoods, typically within metropolitan areas. I find that concentrating former prisoners in the same neighborhoods leads to significantly higher recidivism rates than if ex-prisoners were more dispersed across neighborhoods. The reasons why ex-prisoners concentrate in a select few urban neighborhoods include personal factors such as social ties to the neighborhood, but they also include institutional and structural barriers such as parole policies and housing market dynamics. Policy solutions that disperse the geographic concentration of former prisoners, while leading to some geographic displacement of recidivism, would likely yield a net reduction in recidivism in aggregate.