bluuebunny/crossref_metadata_2025 huggingface dataset:
Recruitment of bone marrow CD11b+Gr-1+ cells by polymeric nanoparticles for antigen cross-presentation
Authors: Yang Ya-Wun , Luo Wen-Hui
Published: March 2017

The objective of this study was to investigate the function of poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) on the activation of antigen-specific CD8+T cell responses via the CD11b+Gr−1+myeloid subpopulations in murine bone marrow (BM). PLGA NPs containing ovalbumin (OVA) were fabricated by the double-emulsion method. The CD11b+Gr-1lowLy-6Chighand CD11b+Gr-1highLy-6Clowsubsets from mice bone marrow were sorted and treated with the PLGA/OVA NPs, followed by co-culture with the carboxyfluorescein succinimidyl ester (CFSE)-labelled OT-I CD8+cells. Co-culture of OT-I CD8+T cells with PLGA/OVA NPs-primed CD11b+Gr-1+subsets upregulated the expression of IL-2, TNF-α, INF-γ, granzyme B, and perforin, resulting in proliferation of CD8+T cells and differentiation into effector cytotoxic T lymphocytes (CTLs).In vivoproliferation of CFSE-labelled OT-I CD8+cells in response to OVA was also obtained in the animals immunized with PLGA/OVA NPs. The results presented in this study demonstrate the ability of polymeric NPs to recruit two CD11b+Gr−1+myeloid subsets for effective presentation of exogenous antigen to OT-I CD8+T cells in the context of major histocompatibility complex (MHC) class I, leading to an induction of antigen-specific cell proliferation and differentiation into effector cells.
Cyclooxygenase‐2 facilitates dengue virus replication and serves as a potential target for developing antiviral agents
Authors: Lin Chun-Kuang , Tseng Chin-Kai , Wu Yu-Hsuan , Liaw Chih-Chuang , Lin Chun-Yu , Huang Chung-Hao , Chen Yen-Hsu , Lee Jin-Ching
Published: March 2017

Cyclooxygenase-2 (COX-2) is one of the important mediators of inflammation in response to viral infection, and it contributes to viral replication, for example, cytomegalovirus or hepatitis C virus replication. The role of COX-2 in dengue virus (DENV) replication remains unclear. In the present study, we observed an increased level of COX-2 in patients with dengue fever compared with healthy donors. Consistent with the clinical data, an elevated level of COX-2 expression was also observed in DENV-infected ICR suckling mice. Using cell-based experiments, we revealed that DENV-2 infection significantly induced COX-2 expression and prostaglandin E2 (PGE2) production in human hepatoma Huh-7 cells. The exogenous expression of COX-2 or PGE2 treatment dose-dependently enhanced DENV-2 replication. In contrast, COX-2 gene silencing and catalytic inhibition sufficiently suppressed DENV-2 replication. In an ICR suckling mouse model, we identified that the COX-2 inhibitor NS398 protected mice from succumbing to life-threatening DENV-2 infection. By using COX-2 promoter-based analysis and specific inhibitors against signaling molecules, we identified that NF-κB and MAPK/JNK are critical factors for DENV-2-induced COX-2 expression and viral replication. Altogether, our results reveal that COX-2 is an important factor for DENV replication and can serve as a potential target for developing therapeutic agents against DENV infection.
High Thermoelectric Power Factor of a Diketopyrrolopyrrole-Based Low Bandgap Polymer via Finely Tuned Doping Engineering
Authors: Jung In Hwan , Hong Cheon Taek , Lee Un-Hak , Kang Young Hun , Jang Kwang-Suk , Cho Song Yun
Published: March 2017

We studied the thermoelectric properties of a diketopyrrolopyrrole-based semiconductor (PDPP3T) via a precisely tuned doping process using Iron (III) chloride. In particular, the doping states of PDPP3T film were linearly controlled depending on the dopant concentration. The outstanding Seebeck coefficient of PDPP3T assisted the excellent power factors (PFs) over 200 μW m−1K−2 at the broad range of doping concentration (3–8 mM) and the maximum PF reached up to 276 μW m−1K−2, which is much higher than that of poly(3-hexylthiophene), 56 μW m−1K−2. The high-mobility of PDPP3T was beneficial to enhance the electrical conductivity and the low level of total dopant volume was important to maintain high Seebeck coefficients. In addition, the low bandgap PDPP3T polymer effiectively shifted its absorption into near infra-red area and became more colorless after doping, which is great advantage to realize transparent electronic devices. Our results give importance guidance to develop thermoelectric semiconducting polymers and we suggest that the use of low bandgap and high-mobility polymers, and the accurate control of the doping levels are key factors for obtaining the high thermoelectric PF.
Minocycline treatment suppresses juvenile development and growth by attenuating insulin/TOR signaling in Drosophila animal model
Authors: Yun Hyun Myoung , Noh Sujin , Hyun Seogang
Published: March 2017

Minocycline is a broad spectrum, semi-synthetic tetracycline analog that is used to treat bacterial infection. Recently, this drug has been receiving increasing attention for its non-antibiotic properties, including anti-inflammatory, tumor suppressive, and neuroprotective effects. Drosophila is a useful model organism for studying human metabolism and disease. In this study, we investigated the effects of minocycline on juvenile development and growth in Drosophila. Feeding minocycline to Drosophila larvae suppresses larval body growth and delays the timing of pupation in a dose-dependent manner. We found that the drug treatment decreased the activated form of Akt and S6K in peripheral tissues, which suggested that the insulin/target of rapamycin (TOR) signaling had been attenuated. Specifically enhancing TOR activity in the prothoracic gland (PG), the ecdysone-generating organ, attenuated the drug-induced developmental delay, which is consistent with the critical role of PG’s TOR signaling in determining pupation time. Our results reveal previously unrecognized effects of minocycline and offer a new potential therapeutic opportunity for various pathological conditions associated with insulin/TOR signaling.
Tuning the multiferroic mechanisms of TbMnO3 by epitaxial strain
Authors: Shimamoto Kenta , Mukherjee Saumya , Manz Sebastian , White Jonathan S. , Trassin Morgan , Kenzelmann Michel , Chapon Laurent , Lippert Thomas , Fiebig Manfred , Schneider Christof W. , Niedermayer Christof
Published: March 2017

A current challenge in the field of magnetoelectric multiferroics is to identify systems that allow a controlled tuning of states displaying distinct magnetoelectric responses. Here we show that the multiferroic ground state of the archetypal multiferroic TbMnO3 is dramatically modified by epitaxial strain. Neutron diffraction reveals that in highly strained films the magnetic order changes from the bulk-like incommensurate bc-cycloidal structure to commensurate magnetic order. Concomitant with the modification of the magnetic ground state, optical second-harmonic generation (SHG) and electric measurements show an enormous increase of the ferroelectric polarization, and a change in its direction from along the c- to the a-axis. Our results suggest that the drastic change of multiferroic properties results from a switch of the spin-current magnetoelectric coupling in bulk TbMnO3 to symmetric magnetostriction in epitaxially-strained TbMnO3. These findings experimentally demonstrate that epitaxial strain can be used to control single-phase spin-driven multiferroic states.
Ultra-wide range field-dependent measurements of the relaxivity of Gd1−xEuxVO4 nanoparticle contrast agents using a mechanical sample-shuttling relaxometer
Authors: Chou Ching-Yu , Abdesselem Mouna , Bouzigues Cedric , Chu Minglee , Guiga Angelo , Huang Tai-Huang , Ferrage Fabien , Gacoin Thierry , Alexandrou Antigoni , Sakellariou Dimitris
Published: March 2017

The current trend for Magnetic Resonance Imaging points towards higher magnetic fields. Even though sensitivity and resolution are increased in stronger fields, T1 contrast is often reduced, and this represents a challenge for contrast agent design. Field-dependent measurements of relaxivity are thus important to characterize contrast agents. At present, the field-dependent curves of relaxivity are usually carried out in the field range of 0 T to 2 T, using fast field cycling relaxometers. Here, we employ a high-speed sample shuttling device to switch the magnetic fields experienced by the nuclei between virtually zero field, and the center of any commercial spectrometer. We apply this approach on rare-earth (mixed Gadolinium-Europium) vanadate nanoparticles, and obtain the dispersion curves from very low magnetic field up to 11.7 T. In contrast to the relaxivity profiles of Gd chelates, commonly used for clinical applications, which display a plateau and then a decrease for increasing magnetic fields, these nanoparticles provide maximum contrast enhancement for magnetic fields around 1–1.5 T. These field-dependent curves are fitted using the so-called Magnetic Particle (MP) model and the extracted parameters discussed as a function of particle size and composition. We finally comment on the new possibilities offered by this approach.
Novel hypophysiotropic AgRP2 neurons and pineal cells revealed by BAC transgenesis in zebrafish
Authors: Shainer Inbal , Buchshtab Adi , Hawkins Thomas A. , Wilson Stephen W. , Cone Roger D. , Gothilf Yoav
Published: March 2017

The neuropeptide agouti-related protein (AgRP) is expressed in the arcuate nucleus of the mammalian hypothalamus and plays a key role in regulating food consumption and energy homeostasis. Fish express two agrp genes in the brain: agrp1, considered functionally homologous with the mammalian AgRP, and agrp2. The role of agrp2 and its relationship to agrp1 are not fully understood. Utilizing BAC transgenesis, we generated transgenic zebrafish in which agrp1- and agrp2-expressing cells can be visualized and manipulated. By characterizing these transgenic lines, we showed that agrp1-expressing neurons are located in the ventral periventricular hypothalamus (the equivalent of the mammalian arcuate nucleus), projecting throughout the hypothalamus and towards the preoptic area. The agrp2 gene was expressed in the pineal gland in a previously uncharacterized subgroup of cells. Additionally, agrp2 was expressed in a small group of neurons in the preoptic area that project directly towards the pituitary and form an interface with the pituitary vasculature, suggesting that preoptic AgRP2 neurons are hypophysiotropic. We showed that direct synaptic connection can exist between AgRP1 and AgRP2 neurons in the hypothalamus, suggesting communication and coordination between AgRP1 and AgRP2 neurons and, therefore, probably also between the processes they regulate.
Complete genome sequencing and antibiotics biosynthesis pathways analysis of Streptomyces lydicus 103
Authors: Jia Nan , Ding Ming-Zhu , Luo Hao , Gao Feng , Yuan Ying-Jin
Published: March 2017

More and more new natural products have been found in Streptomyces species, which become the significant resource for antibiotics production. Among them, Streptomyces lydicus has been known as its ability of streptolydigin biosynthesis. Herein, we present the genome analysis of S. lydicus based on the complete genome sequencing. The circular chromosome of S. lydicus 103 comprises 8,201,357 base pairs with average GC content 72.22%. With the aid of KEGG analysis, we found that S. lydicus 103 can transfer propanoate to succinate, glutamine or glutamate to 2-oxoglutarate, CO2 and L-glutamate to ammonia, which are conducive to the the supply of amino acids. S. lydicus 103 encodes acyl-CoA thioesterase II that takes part in biosynthesis of unsaturated fatty acids, and harbors the complete biosynthesis pathways of lysine, valine, leucine, phenylalanine, tyrosine and isoleucine. Furthermore, a total of 27 putative gene clusters have been predicted to be involved in secondary metabolism, including biosynthesis of streptolydigin, erythromycin, mannopeptimycin, ectoine and desferrioxamine B. Comparative genome analysis of S. lydicus 103 will help us deeply understand its metabolic pathways, which is essential for enhancing the antibiotic production through metabolic engineering.
Upregulation of skeletal muscle PGC-1α through the elevation of cyclic AMP levels by Cyanidin-3-glucoside enhances exercise performance
Authors: Matsukawa Toshiya , Motojima Hideko , Sato Yuki , Takahashi Shinya , Villareal Myra O. , Isoda Hiroko
Published: March 2017

Regular exercise and physical training enhance physiological capacity and improve metabolic diseases. Skeletal muscles require peroxisome proliferator-activated receptor-gamma coactivator-1α (PGC-1α) in the process of their adaptation to exercise owing to PGC-1α’s ability to regulate mitochondrial biogenesis, angiogenesis, and oxidative metabolism. Cyanidin-3-glucoside (Cy3G) is a natural polyphenol and a nutraceutical factor, which has several beneficial effects on human health. Here, the effect of Cy3G on exercise performance and the underlying mechanisms involved were investigated. ICR mice were given Cy3G (1 mg/kg, orally) everyday and made to perform weight-loaded swimming exercise for 15 days. The endurance of mice orally administered with Cy3G was improved, enabling them to swim longer (time) and while the levels of exercise-induced lactate and fatigue markers (urea nitrogen, creatinine and total ketone bodies) were reduced. Additionally, the expression of lactate metabolism-related genes (lactate dehydrogenase B and monocarboxylate transporter 1) in gastrocnemius and biceps femoris muscles was increased in response to Cy3G-induced PGC-1α upregulation. In vitro, using C2C12 myotubes, Cy3G-induced elevation of intracellular cyclic AMP levels increased PGC-1α expression via the Ca2+/calmodulin-dependent protein kinase kinase pathway. This study demonstrates that Cy3G enhances exercise performance by activating lactate metabolism through skeletal muscle PGC-1α upregulation.
Wide dynamic range enrichment method of semiconducting single-walled carbon nanotubes with weak field centrifugation
Authors: Reis Wieland G. , Tomović Željko , Weitz R. Thomas , Krupke Ralph , Mikhael Jules
Published: March 2017

The potential of single–walled carbon nanotubes (SWCNTs) to outperform silicon in electronic application was finally enabled through selective separation of semiconducting nanotubes from the as-synthesized statistical mix with polymeric dispersants. Such separation methods provide typically high semiconducting purity samples with narrow diameter distribution, i.e. almost single chiralities. But for a wide range of applications high purity mixtures of small and large diameters are sufficient or even required. Here we proof that weak field centrifugation is a diameter independent method for enrichment of semiconducting nanotubes. We show that the non-selective and strong adsorption of polyarylether dispersants on nanostructured carbon surfaces enables simple separation of diverse raw materials with different SWCNT diameter. In addition and for the first time, we demonstrate that increased temperature enables higher purity separation. Furthermore we show that the mode of action behind this electronic enrichment is strongly connected to both colloidal stability and protonation. By giving simple access to electronically sorted SWCNTs of any diameter, the wide dynamic range of weak field centrifugation can provide economical relevance to SWCNTs.
Genetic association between the cyclin-dependent kinase inhibitor gene p27/Kip1 polymorphism (rs34330) and cancer susceptibility: a meta-analysis
Authors: Cheng Xiao-Ke , Wang Xue-Jun , Li Xiao-Dong , Ren Xue-Qun
Published: March 2017

The p27 rs34330 (-79C/T) polymorphism has been widely studied for human cancer susceptibility. The current findings, however, still remained controversial. Therefore, we performed the meta-analysis to provide a more accurate result. Eligible studies were identified from PubMed database up to June 2015. The association of p27 rs34330 polymorphism and cancer susceptibility was estimated with odds ratios and corresponding 95% confidence intervals. The meta-analysis was performed with Stata 12. A total of ten studies with 11,214 cases and more than 8,776 controls were included in the meta-analysis (including breast, lung, thyroid, endometrial, and hepatocellular cancer). In pooled analysis, p27 gene rs34330 polymorphism significantly increased the cancer susceptibility. Subgroup analysis indicated that the elevated risk was observed under all the genetic models for Asians and under three genetic models for Caucasians. Results of sensitivity analysis were similar to the overall results. The results suggested that the p27 rs34330 polymorphism increased the cancer susceptibility, especially in Asians. Further well-designed and large sample size studies are warranted to verify the conclusion.
Extreme adaptations for probable visual courtship behaviour in a Cretaceous dancing damselfly
Authors: Zheng Daran , Nel André , Jarzembowski Edmund A. , Chang Su-Chin , Zhang Haichun , Xia Fangyuan , Liu Haoying , Wang Bo
Published: March 2017

Courtship behaviours, frequent among modern insects, have left extremely rare fossil traces. None are known previously for fossil odonatans. Fossil traces of such behaviours are better known among the vertebrates, e.g. the hypertelic antlers of the Pleistocene giant deerMegaloceros giganteus. Here we describe spectacular extremely expanded, pod-like tibiae in males of a platycnemidid damselfly from mid-Cretaceous Burmese amber. Such structures in modern damselflies, help to fend off other suitors as well as attract mating females, increasing the chances of successful mating. Modern Platycnemidinae and Chlorocyphidae convergently acquired similar but less developed structures. The new findings provide suggestive evidence of damselfly courtship behaviour as far back as the mid-Cretaceous. These data show an unexpected morphological disparity in dancing damselfly leg structure, and shed new light on mechanisms of sexual selection involving intra- and intersex reproductive competition during the Cretaceous.
Rigid High Temperature Heat-Shrinkable Polyimide Tubes with Functionality as Reducer Couplings
Authors: Kong Deyan , Xiao Xinli
Published: March 2017

Flexible and semi-rigid heat-shrinkable tubes (HSTs) have been used in thousands of applications, and here rigid high temperature HSTs are reported for the first time. These rigid HSTs are prepared with shape memory polyimides possessing glass transition temperatures (Tgs) from 182 to 295 °C, and the relationships between Tg and their molecular structures are studied. The polyimide HSTs (PIHSTs) can fix expanded diameters and shrink back to original diameters very well, and the mechanisms of their heat-shrinkage performance are discussed. Their differences from commercially available HSTs in heat-shrinkage are also analyzed. They can withstand low temperature of −196 °C, much lower than those of other HSTs. The PIHSTs can also connect subjects of different sizes by heat-shrinkage and then fix them upon cooling like reducer couplings, and the possible mechanisms of their reducer coupling effect are analyzed. With their unique characteristics, PIHSTs will expand the application areas of HSTs enormously.
Targeting Glycans of HIV Envelope Glycoproteins for Vaccine Design
Authors: Behrens Anna-Janina , Seabright Gemma E. , Crispin Max
Published: March 2017

The surface of the envelope spike of the human immunodeficiency virus (HIV) is covered with a dense array of glycans, which is sufficient to impede the host antibody response while maintaining a window for receptor recognition. The glycan density significantly exceeds that typically observed on self glycoproteins and is sufficiently high to disrupt the maturation process of glycans, from oligomannose- to complex-type glycosylation, that normally occurs during glycoprotein transit through the secretory system. It is notable that this generates a degree of homogeneity not seen in the highly mutated protein moiety. The conserved, close glycan packing and divergences from default glycan processing give a window for immune recognition. Encouragingly, in a subset of individuals, broadly neutralizing antibodies (bNAbs) have been isolated that recognize these features and are protective in passive-transfer models. Here, we review the recent advances in our understanding of the glycan shield of HIV and outline the strategies that are being pursued to elicit glycan-binding bNAbs by vaccination.
Design, Synthesis and Evaluation of Mucin Glycopeptide Based Cancer Vaccine
Authors: Sun Zhanyi , Chen Puguang , Liu Yanfang , Li Yanmei
Published: March 2017

Immunotherapy is one of the most effective techniques for the treatment of diseases. Anti-tumor vaccines have been widely researched. Mucin glycopeptides are considered to be one of the most promising antigens for anti-tumor vaccines. Mucin glycopeptides have weak immunogenicity and numerous immune-stimulating structures have been incorporated through chemical synthesis. In this chapter, we mainly focus on the mucin-based glycopeptide antitumor vaccines, including their design, synthesis and evaluation.
Carbon nanotube-enhanced double-walled phase-change microcapsules for thermal energy storage
Authors: Huang Yi-Tian , Zhang He , Wan Xue-Juan , Chen Da-Zhu , Chen Xue-Fei , Ye Xing , Ouyang Xing , Qin Si-Yin , Wen Hai-Xia , Tang Jiao-Ning
Published: March 2017

Carbon nanotube-incorporated double-walled phase-change microcapsules with excellent thermal and mechanical properties were realized via a facile layer-by-layer self-assembly technique.
Fluorescence detection of dopamine based on nitrogen-doped graphene quantum dots and visible paper-based test strips
Authors: Chen Xueqian , zheng Na , Chen Shufan , Ma Qiang
Published: March 2017

Novel fluorescence detection of dopamine based on nitrogen-doped graphene quantum dots and visible paper-based test strips.
Synthesis of coenzyme Q0 through divanadium-catalyzed oxidation of 3,4,5-trimethoxytoluene with hydrogen peroxide
Authors: Zalomaeva Olga V. , Evtushok Vasilii Yu. , Maksimov Gennadii M. , Maksimovskaya Raisa I. , Kholdeeva Oxana A.
Published: March 2017

The divanadium-substituted polyoxometalate (Bu4N)5−nHn[γ-PW10V2O40] (n = 1–2) is an efficient and recyclable catalyst used for the synthesis of coenzyme Q0 using hydrogen peroxide as a green oxidant.
Preparing artificial latexes using a switchable hydrophilicity solvent
Authors: Su Xin , Jessop Philip G. , Cunningham Michael F.
Published: March 2017

Artificial latexes of poly(butyl methacrylate) (PBMA), natural rubber, and other polymers were separately prepared from the bulk polymer using the CO2-responsive switchable hydrophilicity solvent N,N-dicyclohexylmethylamine (Cy2NMe) with the help of CO2.
Metal-free phosphonation of heteroarene N-oxides with trialkyl phosphite at room temperature
Authors: Chen Ming-Tao , You Xia , Bai Li-Gang , Luo Qun-Li
Published: March 2017

Heteroarene N-oxides were successfully converted to heteroarylphosphonates in a very short time under mild conditions through in situ activation with CBrCl3.
Copolymerization of norbornene and butyl methacrylate at elevated temperatures by a single centre nickel catalyst bearing bulky bis(α-diimine) ligand with strong electron-withdrawing groups
Authors: He Xiaohui , Deng Yingjiao , Jiang Xiong , Wang Zijie , Yang Yingping , Han Zhilong , Chen Defu
Published: March 2017

Bis(α-diimine) single nickel(ii) catalyst with strong electron-withdrawing group was applied to catalyze polymerization and copolymerization of norbornene and butyl methacrylate.
One-pot synthesis of pH-responsive hyperbranched polymer–peptide conjugates with enhanced stability and loading efficiency for combined cancer therapy
Authors: Cheng Dong-Bing , Yang Pei-Pei , Cong Yong , Liu Fu-Hua , Qiao Zeng-Ying , Wang Hao
Published: March 2017

Nanoparticles as drug-delivery systems have received significant attention due to their merits such as prolonged circulation time and passive targeting of a tumor site.
Explicit roles of diverse directing groups in determining transition state energy and reaction exothermicity of C–H activation pathways
Authors: Zhang Lei , Fang De-Cai
Published: March 2017

Effects of directing groups on the C–H activation transition state.
Efficiency of hydrophobic phosphonium ionic liquids and DMSO as recyclable cellulose dissolution and regeneration media
Authors: Holding Ashley J. , Parviainen Arno , Kilpeläinen Ilkka , Soto Ana , King Alistair W. T. , Rodríguez Héctor
Published: March 2017

Hydrophobic, long-chain tetraalkylphosphonium acetate salts (ionic liquids) were combined with DMSO and the feasibility of these solvent systems for cellulose dissolution and regeneration was studied.
Pine-branch-like TiO2 nanofibrous membrane for high efficiency strong corrosive emulsion separation
Authors: Zhang Yuanyuan , Chen Yuee , Hou Lanlan , Guo Fengyun , Liu Jingchong , Qiu Shanshan , Xu Yue , Wang Nü , Zhao Yong
Published: March 2017

A bioinspired pine-branch-like TiO2 membrane for high efficiency strong corrosive acidic, basic and salt emulsion separation.
Highly efficient blueish-green fluorescent OLEDs based on AIE liquid crystal molecules: from ingenious molecular design to multifunction materials
Authors: Wang Yafei , Liao Yuanwei , Cabry Christopher P. , Zhou Di , Xie Guohua , Qu Zuoming , Bruce Duncan W. , Zhu Weiguo
Published: March 2017

Two novel aggregation-induced emission-based (AIE) liquid crystal materials of TPE-PBN and TPE-2PBN have been prepared and characterized.
Facile fabrication of homogeneous and gradient plasmonic arrays with tunable optical properties via thermally regulated surface charge density
Authors: Ye Shunsheng , Wang Hongyu , Su Hongyang , Chang Lingxia , Wang Shuli , Zhang Xuemin , Zhang Junhu , Yang Bai
Published: March 2017

Homogeneous and gradient plasmonic arrays with tunable optical properties were fabricated by regulating the surface charge density of polymer films.
Light-directed growth of metal and semiconductor nanostructures
Authors: Tan Che , Qin Chu , Sadtler Bryce
Published: March 2017

This Review article explores the use of illumination to direct the growth of metal and semiconductor nanostructures.
Solution-processed visible-blind UV-A photodetectors based on CH3NH3PbCl3 perovskite thin films
Authors: Zheng Erjin , Yuh Brian , Tosado Gabriella A. , Yu Qiuming
Published: March 2017

Solution-processed visible-blind UV-A photodetectors based on smooth, pinhole-free CH3NH3PbCl3 perovskite thin films with a high UV-visible rejection ratio.
kP ‐stable regions in the space of PID controller coefficients
Authors: Almodaresi Elham , Bozorg Mohammad
Published: March 2017

Evaluating a set of coefficients of a PID controller that stabilises a given plant is an important topic in designing such a controller. In the literature, the stability boundaries of the coefficients are already computed in the kP –kI –kD space. However, in the existing methods, one of the coefficients must be swept to compute the stable regions in the plane of the two other coefficients. A novel method is presented to compute the regions in the plane of two controller coefficients such that some stable interval exists for the third coefficient. Therefore, the stability crossing boundaries are no longer required to be computed. The main idea used here is to compute the controller coefficients where the Nyquist plot gets tangent to the real axis and the values where the plot has self‐intersections on the real axis. This leads to the main contribution of the study that eliminates the need to sweep the proportional coefficient to plot the stability domains in the kI /kP ‐kD /kP plane.
Distributed output feedback model predictive control for a team of coupled linear subsystems
Authors: Liu Jiang , Xiao Haiyang
Published: March 2017

A distributed output feedback model predictive control (MPC) algorithm is proposed for a team of linear discrete‐time subsystems, for which the states are not measurable. The subsystems are coupled by the cost function. A synchronous update strategy is adopted to formulate a tractable optimisation problem in distributed manner. The terminal controller is specified as the form of output feedback. The weight matrix shared by the terminal region and the terminal cost is designed by solving one optimisation problem. Thereby the terminal region is positively invariant with the terminal controller. Furthermore, the compatibility constraint is tailored for each subsystem to confine the deviation between the real outputs and its assumed ones. The recursive feasibility of the resulting optimisation problem is ensured and the stability of the whole system in closed‐loop operation is guaranteed. Finally, a numerical example is given to illustrate the effectiveness of the proposed algorithm, which can perform faster than the corresponding centralised MPC in spite of a little higher cost.
Cross‐voltage short‐circuit calculation for mixed‐voltage quadruple‐circuit lines on the same tower
Authors: Zheng Tao , Zhang Jiaqin , Wu Dan , Huang Shaofeng , Wang Xiaoli
Published: March 2017

Cross‐voltage faults, i.e. multi‐circuit faults that occur between different voltage level systems, in mixed‐voltage quadruple‐circuit transmission lines occur at times. The short‐circuit calculations, which are the basis of the relay protection settings, for different faults are required. This study proposes a new method based on the theory of multiple fault analysis. First, the cross‐voltage fault is regarded as a double multiple fault of the system. By retaining the fault nodes and the ground node, while eliminating all the intermediate nodes, the equivalent impedance of each sequence is obtained. Next, the fault reference phase is selected and the two‐port network of each sequence that belongs to the reference phase is formed. Further, the port voltages of each sequence are transferred to a special phase using phase‐shifting transformers. Then, a unified composite sequence network is formed according to the boundary conditions of the special phase. Finally, a set of equations are listed based on the composite sequence network in order to determine the fault currents and voltages. The simulation results in PSCAD agree well with the results calculated using the above algorithm, verifying the accuracy of this method.
Process for fabricating microactuator membranes of piezoelectric inkjet print head using multi‐step deep reactive ion etching process
Authors: Wang Wenqiang , Li Chen , Xu Wencai , Zou Helin
Published: March 2017

As part of an effort to develop piezoelectric inkjet print head (PIPH), a process for fabricating its Si‐cups and actuator membranes of multi‐layered structures was investigated. The manufacture of this device was enabled by the use of deep reactive ion etching (DRIE). Based on that, multi‐step DRIE process was proposed to etch the multi‐layered actuator membranes on silicon on insulator wafers. Due to the appropriate parameters of the etching process, undesirable effects, such as Si grasses, notching effect of Si‐cups and the bowing formation on the sidewalls, were also avoided. The way to eliminate the over‐etching of SiO2 membranes by controlling the appropriate platen power and process duration simultaneously was also presented. High quality PIPH actuator membranes were finally obtained, making great contributes to the successful inkjet test.
Anisotropic free-discontinuity functionals as theΓ-limit of second-order elliptic functionals
Authors: Bach Annika
Published: March 2017

We provide an approximation result for free-discontinuity functionals of the form

        𝓕(u) = ∫Ωf(x, u, ∇u)dx + ∫Su∩Ωθ(x, νu)d𝓗n−1,     u ∈ SBV2(Ω),

wherefis quadratic in the gradient-variable andθis an arbitrary smooth Finsler metric. The approximating functionals are of Ambrosio-Tortorelli type and depend on the Hessian of the edge variable through a suitable nonhomogeneous metricϕ.
Elective Primary or Secondary Delayed Sternal Closure Improves Outcome in Severely Compromised Patients
Authors: Calafiore Antonio , Sheikh Azmat , Alfonso Juan , Tantawi Tarek , Maklouf Belgeit , Shawki Ahmed , Allam Ahmed , Awadi Mohammed , Osman Ahmed , Habib Aly , Di Mauro Michele
Published: March 2017

Background Delayed sternal closure (DSC) in patients with severely compromised preoperative hemodynamics can be helpful as the chest sometimes cannot be able to contain both lungs and heart. We report our experience to evaluate the midterm results of this strategy in an adult population.

Materials and Methods From May 2009 till July 2015, 33 patients had DSC as first treatment of severe hemodynamic deterioration after cardiac surgery. Surgical procedures were valvular (9.27%) or coronary artery bypass grafting + others (24.73%). Stepwise logistic regression (SLR) showed that patients with lower ejection fraction, dilated right ventricle, and severe pulmonary hypertension were more likely to need DSC. Patients were divided in two groups: group A (n = 17), when the sternum was reopened before any hemodynamic collapse, or was never closed, and group B (n = 16), when the sternum was reopened after hemodynamic collapse.

Results Inhospital mortality was 39% (n = 13), 18% in group A and 62% in group B (p < 0.0001). In 28 patients where the sternum was reopened, cardiac index increased from 1.7 (1.6, 1.9) L/m2 to 2.8 (2.4, 3) L/m2, p < 0.0001. The sternum was closed in 28 patients (85%), 94% in group A and 75% in group B (p = 0.13), after a median of 4 (2.5) days. SLR showed that only group B (p < 0.0001) was a risk factor for early death. Two-year survival was 48 ± 9%, higher in group A (71 ± 13) than in group B (25 ± 11), p < 0.0001. Cox's analysis showed that group B (p < 0.0001) and redo (p < 0.0001) were risk factors for lower survival.

Conclusion Elective DSC represents a useful strategy in severely compromised patients, entailing an improvement of hemodynamics and a higher survival.
The Ethics of Teaching Physicians Electronic Fetal Monitoring: And Now for the Rest of the Story
Authors: Sartwelle Thomas , Johnston James , Arda Berna
Published: March 2017

Electronic fetal monitoring (EFM) does not predict or prevent cerebral palsy (CP), but this myth remains entrenched in medical training and practice. The continued use of this ineffectual diagnostic modality increases the cesarean section rate with concomitant harms to mothers and babies alike. EFM, as it is used in defensive medical practice, is a violation of patient autonomy and raises serious ethical concerns. This review addresses the need for improved graduate medical education so that physicians and medical residents are taught both sides of the EFM–CP story.
Coronary Endarterectomy or Patch Angioplasty for Diffuse Left Anterior Descending Artery Disease
Authors: Pirundini Paul , Leshem Eyal , Consalvi Carrie , McGurk Siobhan , King Quincy , Loberman Dan , Bitan Ohad
Published: March 2017

Background Coronary endarterectomy and patch angioplasty for the left anterior descending (LAD) artery have been shown to be effective adjunct techniques to surgical revascularization for severe coronary lesions. The objective of this study is to review the short- and long-term results of these two methods in our institution.

Methods We retrospectively reviewed 166 consecutive patients who underwent internal thoracic artery grafting to the LAD, with either adjunct endarterectomy (95 patients) or patch angioplasty (71 patients) between 2002 and 2014. We compared the early and late outcomes between groups.

Results The endarterectomy patients were older than the patch angioplasty patients (71 vs. 67 years, p = 0.007) and had lower rates of recent myocardial infarction (25% vs. 45%, respectively, p = 0.008). Median pulmonary bypass times and aortic cross clamp times were significantly longer in the endarterectomy group compared with the patch angioplasty group by 47 minutes (p < 0.001) and 42 minutes (p < 0.001), respectively. Median follow-up time was 6.9 years. No significant differences in operative mortality, perioperative myocardial infarction, and long-term survival were found. Freedom from percutaneous coronary intervention at 1 and 5 years was significantly higher in the endarterectomy group compared with the patch angioplasty group (p = 0.002).

Conclusions Endarterectomy and patch angioplasty are comparable methods to reach complete revascularization for highly selected patients with diffuse atherosclerotic disease in the LAD. Compared with patch angioplasty, complete extraction of the atherosclerotic plaque with an endarterectomy leads to similar short-term outcomes and long-term survival while significantly reducing the need for further interventions in the future.
Occipitosacral Fusion for Multiple Vertebral Fractures with Kyphotic Deformity in a Patient with Mutilating Rheumatoid Arthritis: A Case Report
Authors: Tanouchi Tetsu , Shimizu Takachika , Ino Masatake , Toda Naofumi , Manabe Nodoka , Itoh Kanako , Fueki Keisuke
Published: March 2017

Osteoporotic vertebral fractures are well-known complications of rheumatoid arthritis. The management of multiple vertebral fractures with kyphotic deformity is controversial. We present a case of a patient with mutilating rheumatoid arthritis who had multiple vertebral fractures with kyphotic deformity after occipitothoracic fusion for rheumatoid cervical disorder. Occipitosacral fusion was effective to create stable spine with better sagittal alignment in this case, but careful clinical assessment for early detection and management of postoperative insufficient pelvic fracture were required.
Sozioökonomische Gradienten bei der Inanspruchnahme zahnärztlicher Leistungen in Deutschland
Authors: Leonhardt Konrad , Hirsch Christian
Published: March 2017

Ziel der vorliegenden Studie war es Unterschiede in der zahnärztlichen Versorgung in Deutschland in Abhängigkeit vom sozioökonomischen Status (SES) und Haushaltsnettoeinkommen (HHN) zu betrachten. Die Analysen beruhen auf bundesweit repräsentativen Querschnittsbefragungen von Erwachsenen im Alter von 18 bis 79 Jahren (Durchschnittsalter 49,1 Jahre; 55% weiblich) durch den Bertelsmann Gesundheitsmonitor von 2002–2009. Die Zugänglichkeit zur zahnärztlichen Versorgung (im Mittel 2,4 Zahnarztbesuche pro Jahr) war für alle Patienten gleich. Bei höherem HHN zahlten Patienten pro Einkommensgruppe 34 € (95%-Konfidenzintervall [KI]: 6 €–63 €) mehr zu ihrem Zahnersatz zu. Im Vergleich zur niedrigen SES-Schicht hatte die mittlere 1,86 -mal (95%-KI: 1,58–2,18) und die hohe 2,37 -mal (95%-KI: 1,96–2,86) so häufig Zahnzusatzversicherungen abgeschlossen. Mit steigendem SES bzw. HHN nimmt die Fähigkeit zu, Zuzahlungen zum Zahnersatz zu leisten und Zahnzusatzversicherungen abzuschließen. Diese Entwicklung begünstigt stärkere sozioökonomische Diskrepanzen in der zahnmedizinischen Versorgung.
Smoothed particle hydrodynamics method from a large eddy simulation perspective
Authors: Di Mascio A. , Antuono M. , Colagrossi A. , Marrone S.
Published: March 2017

The Smoothed Particle Hydrodynamics (SPH) method, often used for the modelling of the Navier–Stokes equations by a meshless Lagrangian approach, is revisited from the point of view of Large Eddy Simulation (LES). To this aim, the LES filtering procedure is recast in a Lagrangian framework by defining a filter that moves with the positions of the fluid particles at the filtered velocity. It is shown that the SPH smoothing procedure can be reinterpreted as a sort of LES Lagrangian filtering, and that, besides the terms coming from the LES convolution, additional contributions (never accounted for in the SPH literature) appear in the equations when formulated in a filtered fashion. Appropriate closure formulas are derived for the additional terms and a preliminary numerical test is provided to show the main features of the proposed LES-SPH model.
A novel gas-vacuum interface for environmental molecular beam studies
Authors: Johansson Sofia M. , Kong Xiangrui , Papagiannakopoulos Panos , Thomson Erik S. , Pettersson Jan B. C.
Published: March 2017

Molecular beam techniques are commonly used to obtain detailed information about reaction dynamics and kinetics of gas-surface interactions. These experiments are traditionally performed in vacuum and the dynamic state of surfaces under ambient conditions is thereby excluded from detailed studies. Herein we describe the development and demonstration of a new vacuum-gas interface that increases the accessible pressure range in environmental molecular beam (EMB) experiments. The interface consists of a grating close to a macroscopically flat surface, which allows for experiments at pressures above 1 Pa including angularly resolved measurements of the emitted flux. The technique is successfully demonstrated using key molecular beam experiments including elastic helium and inelastic water scattering from graphite, helium and light scattering from condensed adlayers, and water interactions with a liquid 1-butanol surface. The method is concluded to extend the pressure range and flexibility in EMB studies with implications for investigations of high pressure interface phenomena in diverse fields including catalysis, nanotechnology, environmental science, and life science. Potential further improvements of the technique are discussed.
Femtosecond filament initiated, microwave heated cavity-free nitrogen laser in air
Authors: Kartashov Daniil , Shneider Mikhail N.
Published: March 2017

We present the results of numerical modeling of the igniter-heater concept for initiation of standoff, cavity free lasing action in the atmosphere when a femtosecond laser filament is used for plasma generation (igniter) and a microwave heater provides electron-collision pumping of electronic states in molecular nitrogen. By solving numerically the kinetic equation for the energy distribution function of electrons, generated in a femtosecond laser filament and heated by a microwave beam, we identify the conditions enabling single-pass, standoff UV-laser from molecular nitrogen in the atmosphere. The plasma density, the minimum amplitude of the microwave field, and the small-signal gain, necessary to achieve the lasing, are determined. We demonstrate that lasing build up time can be minimized and efficiency improved by using elliptically polarized laser pulses for filamentation. It is shown that realization of the filament-igniter, microwave-heater concept of the sky laser at low altitudes would require a microwave source of hundreds of kilowatt-megawatt power. The required microwave power can be reduced by several orders of magnitude when the igniter-heater scheme is used at the 10–30 km range of altitudes.
Design and modeling of compact phase shifter based on graphene electro-refraction effects
Authors: Hu Xiao , Wang Jian
Published: March 2017

By exploiting the electro-refraction effect of graphene, we present a graphene-based compact phase shifter. The waveguide structure consists of a silica substrate, a high index silicon (Si) vertical slot waveguide, a Si3N4 dielectric spacer, two graphene layers, and two metal electrodes. The phase shifter performance is comprehensively studied in terms of working range, insertion loss, bandwidth, and V2π for transverse magnetic and transverse electric modes. The obtained results show a linear relationship between the applied voltage and phase shift.
Colossal photo-conductive gain in low temperature processed TiO2 films and their application in quantum dot solar cells
Authors: Mandal Debranjan , Goswami Prasenjit N. , Rath Arup K.
Published: March 2017

Colloidal quantum dot (QD) solar cells have seen remarkable progress in recent past to reach the certified efficiency of 10.6%. Anatase titanium oxide (TiO2) is a widely studied n-type widow layer for the collection of photogenerated electrons in QD solar cells. Requirement of high temperature (∼500 °C) processing steps proved to be disadvantageous for its applications in flexible solar cells and roll to roll processing, and it also has adverse commercial implications. Here, we report that solar light exposure to low temperature processed (80 °C–150 °C) TiO2 and niobium doped TiO2 films leads to unprecedented enhancement in their electron densities and electron mobilities, which enables them to be used as efficient n-type layers in quantum dot solar cells. Such photoinduced high conducting states in these films show gradual decay over hours after the light bias is taken off and can be retrieved under solar illumination. On the contrary, TiO2 films processed at 500 °C show marginal photo induced enhancements in their characteristics. In bilayer configuration with PbS QDs, photovoltaic devices based on low temperature processed TiO2 films show improved performance over high temperature processed TiO2 films. The stability of photovoltaic devices also improved in low temperature processed TiO2 films under ambient working conditions.
Macroscopic ferroelectricity and piezoelectricity in nanostructured NaNbO3 ceramics
Authors: Chao Lumen , Hou Yudong , Zheng Mupeng , Yue Yunge , Zhu Mankang
Published: March 2017

NaNbO3 sits at an instability between its ferroelectric and antiferroelectric phases, but its nanoscale polarization behavior is rarely reported. In this work, we produced high-density NaNbO3 nanostructured ceramics with a grain size of 50 nm by spark plasma sintering of nanocrystalline powder, which was obtained by mechanosynthesis. The nanostructured ceramics exhibited a symmetrical ferroelectric loop and increased relative permittivity. We believe that the increased internal stress at the nanoscale stabilized the ferroelectric domain structure, which promoted macroscopic piezoelectricity, demonstrating its potential uses in nanoelectromechanical systems.
Excitonic lasing of strain-free InP(As) quantum dots in AlInAs microdisk
Authors: Lebedev D. V. , Kulagina M. M. , Troshkov S. I. , Vlasov A. S. , Davydov V. Y. , Smirnov A. N. , Bogdanov A. A. , Merz J. L. , Kapaldo J. , Gocalinska A. , Juska G. , Moroni S. T. , Pelucchi E. , Barettin D. , Rouvimov S. , Mintairov A. M.
Published: March 2017

Formation, emission, and lasing properties of strain-free InP(As)/AlInAs quantum dots (QDs) embedded in AlInAs microdisk (MD) cavity were investigated using transmission electron microscopy and photoluminescence (PL) techniques. In MD structures, the QDs have the nano-pan-cake shape with the height of ∼2 nm, the lateral size of 20–50 nm, and the density of ∼5 × 109 cm−2. Their emission observed at ∼940 nm revealed strong temperature quenching, which points to exciton decomposition. It also showed unexpected type-I character, indicating In-As intermixing as confirmed by band structure calculations. We observed lasing of InP(As) QD excitons into whispering gallery modes in MD having the diameter of ∼3.2 μm and providing a free spectral range of ∼27 nm and quality factors up to Q∼13 000. Threshold of ∼50 W/cm2 and spontaneous emission coupling coefficient of ∼0.2 were measured for this MD-QD system.
The formation and decomposition of D2-triazolines derived from Bicyclo[2,2,1]-heptadienes
Authors: Halton B , Woolhouse AD
Published: March 2017

The reactions of a series
of bicyclo[2,2,1]heptadienes with phenyl azide have been examined and the
resultant Δ2-triazolines (2) and (3) characterized. The
photolysis of these latter compounds provides a convenient route to several
exo- and endo-3-aza-tricyclooctenes (6) and (7).