bluuebunny/crossref_metadata_2025 huggingface dataset:
A upconversion luminescene biosensor based on dual-signal amplification for the detection of short DNA species of c-erbB-2 oncogene
Authors: Lan Jianming , Liu Yingxin , Li Li , Wen Fadi , Wu Fang , Han Zhizhong , Sun Weiming , Li Chunyan , Chen Jinghua
Published: April 2016

High-sensitivity detection of trace amounts of c-erbB-2 oncogene was reported to be equal to or surpass the ability of CA 15-3 for early diagnosis and/or follow-up recurrent screening of breast cancer. Therefore, in the current study, by using upconversion nanoparticles (UCNPs), rare earth-doped NaYF4:Yb3+/Er3+as the luminescent labels, a upconversion luminescent (UCL) biosensor based on dual-signal amplification of exonuclease III (ExoIII)-assisted target cycles and long-range self-assembly DNA concatamers was developed for the detection of c-erbB-2 oncogene. The proposed biosensor exhibited ultrasensitive detection with limit as low as 40 aM, which may express the potential of being used in trace analysis of c-erbB-2 oncogene and early diagnosis of breast cancer.
Negative thermal expansion and broad band photoluminescence in a novel material of ZrScMo2VO12
Authors: Ge Xianghong , Mao Yanchao , Liu Xiansheng , Cheng Yongguang , Yuan Baohe , Chao Mingju , Liang Erjun
Published: April 2016

In this paper, we present a novel material with the formula of ZrScMo2VO12 for the first time. It was demonstrated that this material exhibits not only excellent negative thermal expansion (NTE) property over a wide temperature range (at least from 150 to 823 K), but also very intense photoluminescence covering the entire visible region. Structure analysis shows that ZrScMo2VO12 has an orthorhombic structure with the space group Pbcn (No. 60) at room temperature. A phase transition from monoclinic to orthorhombic structure between 70 and 90 K is also revealed. The intense white light emission is tentatively attributed to the n- and p-type like co-doping effect which creates not only the donor- and acceptor-like states in the band gap, but also donor-acceptor pairs and even bound exciton complexes. The excellent NTE property integrated with the intense white-light emission implies a potential application of this material in light emitting diode and other photoelectric devices.
Multivariate optimization of a simple and sensitive method for the determination of secondary biogenic organic compounds in airborne particles
Authors: Mologousi Athanasia I. , Bakeas Evangelos B.
Published: April 2016

In this study, a simple and sensitive method for the determination of biogenic secondary organic aerosol (SOA) in airborne particles, has been optimized and validated.
A hydrogel based rapid test method for detection of Escherichia coli (E. coli) in contaminated water samples
Authors: Gunda Naga Siva Kumar , Chavali Ravi , Mitra Sushanta K.
Published: April 2016

We have formulated a new chemical composition for rapid detection ofEscherichia coli(E. coli) with currently available enzymatic substrates.
A one-step colorimetric acid–base titration sensor using a complementary color changing coordination system
Authors: Cho Hui Hun , Kim Si Hyun , Heo Jun Hyuk , Moon Young Eel , Choi Young Hun , Lim Dong Cheol , Han Kwon-Hoon , Lee Jung Heon
Published: April 2016

A colorimetric acid–base titration sensor allowing one-step quantitative detection of acid content by naked eyes.
Tethered N-heterocyclic carbene–carboranes: unique ligands that exhibit unprecedented and versatile coordination modes at rhodium
Authors: Holmes Jordan , Pask Christopher M. , Fox Mark A. , Willans Charlotte E.
Published: April 2016

Hybrid ligands combining an N-heterocyclic carbene tethered with carboranes covalently coordinate to RhI through both NHC and carborane moieties.
Electrical properties of flexible multi-channel Si nanowire field-effect transistors depending on the number of Si nanowires
Authors: Kim Do Hoon , Lee Su Jeong , Lee Sang Hoon , Myoung Jae-Min
Published: April 2016

In order to secure high drain current and mobility of Si NW-based FETs, flexible multi-channel Si NW FETs were designed and their reliable electrical and mechanical properties were confirmed.
Glucose-sensitive polymer nanoparticles for self-regulated drug delivery
Authors: Zhao Li , Xiao Chunsheng , wang Liyan , Gai Guangqing , Ding Jianxun
Published: April 2016

Glucose-sensitive polymer nanoparticles based on glucose oxidase, concanavalin A, or phenylboronic acid for self-regulated drug delivery have been reviewed.
Combining solid-state NMR spectroscopy with first-principles calculations – a guide to NMR crystallography
Authors: Ashbrook Sharon E. , McKay David
Published: April 2016

DFT calculations are an important tool in assigning and interpreting NMR spectra of solids: we discuss recent developments and their future potential in the context of NMR crystallography.
Application of ordered mesoporous carbon in solid phase microextraction for fast mass transfer and high sensitivity
Authors: Zheng Juan , Wang Kun , Liang Yeru , Zhu Fang , Wu Dingcai , Ouyang Gangfeng
Published: April 2016

High-surface-area ordered mesoporous carbon-coated fiber exhibits a large adsorption amount, fast mass transport and high sensitivity, presenting an attractive potential candidate for pollution enrichment and detection in environmental samples.
Silver-mediated direct trifluoromethoxylation of α-diazo esters via the −OCF3 anion
Authors: Zha Gao-Feng , Han Jia-Bin , Hu Xiao-Qian , Qin Hua-Li , Fang Wan-Yin , Zhang Cheng-Pan
Published: April 2016

Silver-mediated direct trifluoromethoxylation of α-diazo esters and ketosteroid was disclosed.
Sequential detection of multiple phase transitions in model biological membranes using a red-emitting conjugated polyelectrolyte
Authors: Houston Judith E. , Kraft Mario , Scherf Ullrich , Evans Rachel C.
Published: April 2016

Charge-mediated assembly of an anionic poly(thiophene) leads to a highly sensitive probe of membrane order.
Catalysis mechanisms of CO2 and CO methanation
Authors: Miao Bin , Ma Su Su Khine , Wang Xin , Su Haibin , Chan Siew Hwa
Published: April 2016

This review focuses on the mechanisms of CO2 and CO methanation, and catalysts' deactivation.
Economically sustainable scaling of photovoltaics to meet climate targets
Authors: Needleman David Berney , Poindexter Jeremy R. , Kurchin Rachel C. , Marius Peters I. , Wilson Gregory , Buonassisi Tonio
Published: April 2016

Technological and financial innovations are evaluated to determine what can enable sufficient growth of photovoltaics (PV) manufacturing capacity to meet climate-driven PV deployment targets.
Enhancing the hepatic protective effect of genistein by oral administration with stachyose in mice with chronic high fructose diet consumption
Authors: Li Wenfeng , Li Zhao , Han Xiao , Huang Di , Lu Yalong , Yang Xingbin
Published: April 2016

Stachyose enhances absorption and the hepatoprotective effect of genistein in high fructose-fed mice.
Mediterranean diet and faecal microbiota: a transversal study
Authors: Gutiérrez-Díaz I. , Fernández-Navarro T. , Sánchez B. , Margolles A. , González S.
Published: April 2016

The adherence to Mediterrean Diet pattern is associated with higher abundances of Bacteroidetes and lower of Firmicutes.
Nickel-catalyzed hydrocarboxylation of alkynes with formic acid
Authors: Hou Jing , Yuan Ming-Lei , Xie Jian-Hua , Zhou Qi-Lin
Published: April 2016

A protocol for nickel-catalyzed hydrocarboxylation of alkynes with formic acid was developed.
Characterisation of oxygen permeation into a microfluidic device for cell culture by in situ NMR spectroscopy
Authors: Yilmaz Ali , Utz Marcel
Published: April 2016

A compact microfluidic device for normoxic perfusion culture of mammalian cells under in situ metabolomic observation by NMR spectroscopy is presented.
Lipid dynamics in zebrafish embryonic development observed by DESI-MS imaging and nanoelectrospray-MS
Authors: Pirro V. , Guffey S. C. , Sepúlveda M. S. , Mahapatra C. T. , Ferreira C. R. , Jarmusch A. K. , Cooks R. G.
Published: April 2016

Spatial maps of lipid profiles in intact zebrafish embryos and a description of variation through early development.
Discovery of a potential lead compound for treating leprosy with dapsone resistance mutation in M. leprae folP1
Authors: Nisha J. , Ramanathan K. , Nawaz Khan F. , Dhanasekaran D. , Shanthi V.
Published: April 2016

A potential lead compound to overcome dapsone resistance inM. leprae folP1was identified by a virtual screening strategy.
Design, synthesis, and in vitro evaluation of a fluorescently labeled irreversible inhibitor of the catalytic subunit of cAMP-dependent protein kinase (PKACα)
Authors: Coover Robert A. , Luzi Nicole M. , Korwar Sudha , Casile Maria E. , Lyons Charles E. , Peterson Darrell L. , Ellis Keith C.
Published: April 2016

A new fluorescent-labeled inhibitor for PKACα was developed that potently inhibits the kinase (IC50= 11.8 nM), is >100-fold selective for PKACα, and irreversibly labels Cys199.
Ceramic coated polypropylene separators for lithium-ion batteries with improved safety: effects of high melting point organic binder
Authors: Yu Linghui , Jin Yi , Lin Y. S.
Published: April 2016

A study on Al2O3/poly(vinyl alcohol) coated polypropylene separators is presented providing insights into designing high-performance LIB separators with improved safety.
An effective and environment-friendly system for Cu NPs@RGO-catalyzed C–C homocoupling of aryl halides or arylboronic acids in ionic liquids under microwave irradiation
Authors: Zhao Hongyan , Mao Guijie , Han Huatao , Song Jinyi , Liu Yang , Chu Wenyi , Sun Zhizhong
Published: April 2016

Cu NPs@RGO can effectively catalyze Ullmann C–C homocoupling of aryl halides and arylboronic acids under microwave irradiation in green solvent ionic liquid..
Nanotubes with anatase nanoparticulate walls obtained from NH4TiOF3 nanotubes prepared by anodizing Ti
Authors: Torres Ildefonso Zamudio , de Jesús Pérez Bueno José , Torres López Celeste Yunueth , Rojas Luis Lartundo , Mendoza López Maria Luisa , Vong Yunny Meas
Published: April 2016

In this work, titanium dioxide nanoparticulate nanotubes (NP-NT) in anatase phase from ammonium oxyfluorotitanate nanotubes (NT NH4TiOF3) are shown.
Nitrogen-rich hierarchical porous hollow carbon nanofibers for high-performance supercapacitor electrodes
Authors: Zhan Changzhen , Xu Qiang , Yu Xiaoliang , Liang Qinghua , Bai Yu , Huang Zheng-Hong , Kang Feiyu
Published: April 2016

Nitrogen-rich hierarchical porous hollow carbon nanofibers were prepared by concentric electrospinning and subsequent KCl/K2CO3 activation. It shows great prospect in high-performance supercapacitor applications.
Novel luminescent chiral network liquid-crystalline polymers containing Sm(iii) ions
Authors: Yao Bing , Cong Yuehua , Zhang Baoyan , Wang Zeqing , Chen Fei , Sun Cong
Published: April 2016

Chiral network liquid-crystalline polymers with samarium complexes distributed in spiral matrices can emit soft red light when excited.
Correction: High yielding synthesis of 2,2′-bipyridine macrocycles, versatile intermediates in the synthesis of rotaxanes
Authors: Lewis J. E. M. , Bordoli R. J. , Denis M. , Fletcher C. J. , Galli M. , Neal E. A. , Rochette E. M. , Goldup S. M.
Published: April 2016

Correction for ‘High yielding synthesis of 2,2′-bipyridine macrocycles, versatile intermediates in the synthesis of rotaxanes’ by J. E. M. Lewis et al., Chem. Sci., 2016, DOI: 10.1039/c6sc00011h.
From polymers to proteins: the effect of side chains and broken symmetry on the formation of secondary structures within a Wang–Landau approach
Authors: Škrbić Tatjana , Badasyan Artem , Hoang Trinh Xuan , Podgornik Rudolf , Giacometti Achille
Published: April 2016

Protein-like systems are studied using models of increasing complexity starting from a tangent-beads chain and gradually adding the possibility of overlapping for consecutive beads, as well the presence of additional smaller beads mimicking side chains, using Wang–Landau techniques.
Binding TiO2-B nanosheets with N-doped carbon enables highly durable anodes for lithium-ion batteries
Authors: Chen Chaoji , Zhang Bao , Miao Ling , Yan Mengyu , Mai Liqiang , Huang Yunhui , Hu Xianluo
Published: April 2016

Binding TiO2-B nanocrystals with N-doped carbon promotes interfacial lithium storage, leading to a high-capacity and long-life anode.
Si–C–F decorated porous carbon materials: A new class of electrocatalysts for the oxygen reduction reaction
Authors: Abbas Syed Comail , Ding Kui , Liu Qin , Huang Yiyin , Bu Yakun , Wu Jing , Lv Jiangquan , Ghausi Muhammad Arsalan , Wang Yaobing
Published: April 2016

The development of efficient oxygen reduction reaction (ORR) electrocatalysts composed of low cost and earth abundant elements is imperative for several energy systems.
NiCo2O4@MnMoO4core–shell flowers for high performance supercapacitors
Authors: Gu Zhengxiang , Zhang Xiaojun
Published: April 2016

Hierarchical NiCo2O4@MnMoO4core–shell nanomaterial on nickel foam was designedviaa facile hydrothermal method.
Mesoporous silicon nanoparticles for targeted two-photon theranostics of prostate cancer
Authors: Chaix Arnaud , El Cheikh Khaled , Bouffard Elise , Maynadier Marie , Aggad Dina , Stojanovic Vanja , Knezevic Nikola , Garcia Marcel , Maillard Philippe , Morère Alain , Gary-Bobo Magali , Raehm Laurence , Richeter Sébastien , Durand Jean-Olivier , Cunin Frédérique
Published: April 2016

Porous silicon nanoparticles grafted with a mannose-6-phosphate analogue were designed for targeting prostate cancer cells.
Novel persistent phosphors of lanthanide–chromium co-doped yttrium aluminum gallium garnet: design concept with vacuum referred binding energy diagram
Authors: Xu Jian , Ueda Jumpei , Tanabe Setsuhisa
Published: April 2016

We have developed Pr3+–Cr3+ and Tb3+–Cr3+ co-doped Y3Al2Ga3O12 (YAGG) persistent phosphors with orange (Pr3+) and light green (Tb3+) persistent luminescence.
Role of various defects in the photoluminescence characteristics of nanocrystalline Nd2Zr2O7: an investigation through spectroscopic and DFT calculations
Authors: Gupta Santosh K. , Sudarshan K. , Ghosh P. S. , Srivastava A. P. , Bevara S. , Pujari P. K. , Kadam R. M.
Published: April 2016

Photoluminescence in the blue and green regions is observed for the first time in nanocrystals of Nd2Zr2O7 synthesized by gel combustion method. This emission is attributed to the presence of oxygen vacancies.
α-Lipoic acid promotes α-tubulin hyperacetylation and blocks the turnover of mitochondria through mitophagy
Authors: Stoner Michael W. , Thapa Dharendra , Zhang Manling , Gibson Gregory A. , Calderon Michael J. , St. Croix Claudette M. , Scott Iain
Published: April 2016

Lysine acetylation is tightly coupled to the nutritional status of the cell, as the availability of its cofactor, acetyl-CoA, fluctuates with changing metabolic conditions. Recent studies have demonstrated that acetyl-CoA levels act as an indicator of cellular nourishment, and increased abundance of this metabolite can block the induction of cellular recycling programmes. In the present study we investigated the cross-talk between mitochondrial metabolic pathways, acetylation and autophagy, using chemical inducers of mitochondrial acetyl-CoA production. Treatment of cells with α-lipoic acid (αLA), a cofactor of the pyruvate dehydrogenase complex, led to the unexpected hyperacetylation of α-tubulin in the cytosol. This acetylation was blocked by pharmacological inhibition of mitochondrial citrate export (a source for mitochondria-derived acetyl-CoA in the cytosol), was dependent on the α-tubulin acetyltransferase (αTAT) and was coupled to a loss in function of the cytosolic histone deacetylase, HDAC6. We further demonstrate that αLA slows the flux of substrates through autophagy-related pathways, and severely limits the ability of cells to remove depolarized mitochondria through PTEN-associated kinase 1 (PINK1)-mediated mitophagy.
Video anomaly detection and localisation based on the sparsity and reconstruction error of auto‐encoder
Authors: Sabokrou M. , Fathy M. , Hoseini M.
Published: April 2016

A fast and accurate video anomaly detection and localisation method is presented. The speed and localisation accuracy are two ongoing challenges in real‐world anomaly detection. We introduce two novel cubic‐patch‐based anomaly detector where one works based on power of an auto‐encoder (AE) on reconstituting an input video patch and another one is based on the power of sparse representation of an input video patch. It is found that if an AE is efficiently trained on all normal patches, the anomaly patch in testing phase has a more reconstruction error than a normal patch. Also if a sparse AE is learned based on normal training patches, we expect that the given patch to AE is represented sparsely. If the representation is not enough sparse it is considered as a good candidate to be anomaly. For being more fast, these two detectors are combined as a cascade classifier. First, all small patches on test video frame are scanned, those which have not enough sparse representation are resized and sent to next detector for more careful evaluation. The experiment results show that the method mentioned here has a better performance especially in run‐time measure than state‐of‐the‐art methods on two UMN and UCSD benchmarks.
Subclass representation‐based face‐recognition algorithm derived from the structure scatter of training samples
Authors: Xuan Shibin , Xiang Shuenling , Ma Haiying
Published: April 2016

Representation‐based face‐recognition techniques have received attention in the field of pattern recognition in recent years; however, the well‐known works focus mainly on constraint conditions and dictionary learning. Few researchers study, which sample data features determine the performance of representation‐based classification algorithms. To address this problem, the authors define the structure‐scatter degree, which represents the structural features of training sample sets, to determine whether a set is suitable for the representation‐based classification algorithm. Experimental results show that sets with a higher structure scatter more likely allows a classification algorithm to obtain a higher recognition rate. Further, the block contribution degree (DBC) of a training sample set is defined to evaluate whether a sample set is suitable for block‐based sparse‐representation classification algorithms. Experimental results indicate that if the DBC approaches zero, the block technique is unlikely to improve the performance of a representation‐based classification algorithm. Thus, they devise a self‐adaptive optimisation method to generate an optimal block size, an overlapping degree, and a block‐weighting scheme. Finally, they propose the structure scatter‐based subclass representation classification. Experimental results demonstrate that the proposed algorithm not only improves the recognition accuracy of the representation‐based classification algorithm, but also greatly reduces its time complexity.
Multistatic microwave imaging with arrays of planar cavities
Authors: Yurduseven Okan , Gowda Vinay R. , Gollub Jonah N. , Smith David R.
Published: April 2016

The authors present a multistatic imaging system at microwave frequencies based on arrays of planar cavity sub‐apertures, or panels. The cavity imager consists of sets of transmit and receive panels, loaded with radiating irises distributed over the sub‐apertures in an aperiodic pattern. This frequency‐diverse aperture produces distinct radiation patterns as a function of frequency that encode scene information onto a set of measurements; images are subsequently reconstructed using computational imaging approaches. Similar to previously reported computational imaging systems, the cavity‐based imager presents a simple system architecture, minimising the number and expense of components required in traditional microwave imaging systems. The cavity imager builds on previous frequency‐diverse approaches, such as the recently reported metamaterial and air‐filled cavity systems, by utilising frequency‐diverse panels for both the transmit and receive sub‐apertures of the imaging system. Though the panel‐to‐panel architecture has greater sensitivity to calibration error, this implementation nevertheless increases mode diversity and, in the context of a computational imaging system, results in improved image reconstructions.
Dynamic range considerations in code division multiple input multiple output radar
Authors: Monte Lorenzo Lo , Corigliano Thomas A. , Himed Braham , Baker Christopher J.
Published: April 2016

Multiple input multiple output (MIMO) beamforming is examined both theoretically and experimentally to highlight practical performance aspects that require a careful understanding when deciding if the MIMO concept is appropriate for a given application. Specifically, the time division multiplexing (TDM) and code division multiplexing (CDM) cases are compared. While both TDM and CDM form beams that agree closely with predictions, there are significant differences in system performance due to limits on the orthogonality of waveforms that occur when using CDM. These limits are manifested in the peak‐to‐mean sidelobe ratios, resulting in significant and extended range sidelobes consistent with a value approximately equal to the time‐bandwidth product, and fairly independent from the number of transmitters or receivers used. In many cases, these sidelobes fundamentally limit the dynamic range of the radar. Simulations and experiments using a TDM/CDM MIMO radar validated these observations.
Segmental Surface Referencing during Intraoperative Three-dimensional Image-Guided Spine Navigation: An Early Validation with Comparison to Automated Referencing
Authors: Al-Habib Amro F. , Al-Akkad Salah
Published: April 2016

Study Design

Interventional human cadaver study.

Objective

Intraoperative three-dimensional (3-D)-guided navigation improves spine instrumentation accuracy. However, image acquisition may need to be repeated with segment hypermobility or distant target from reference frame (RF). The current study evaluates the usefulness of internal metal fiducials (IMFs) as surface references in enhancing registration accuracy and avoiding repeating imaging.

Methods

Six fresh-frozen cadaveric human torsos were utilized. Posterior C1–T2 exposure was done, and three IMFs were inserted per level; intraoperative 3-D images were then acquired. Two registration methods were utilized: autoregistration (AR, group 1) and point registration using IMF (IMFR, group 2). Registration accuracy was checked by identifying IMFs in both groups. Pedicle screws inserted into C2, C4, C5, and C7 based on the two registration methods (three cadavers each) with RF on C7 and then on C2.

Results

The mean registration error was lower with IMFR compared with AR (0.35 ± 0.5 mm versus 2.02 ± 0.85 mm, p = 0.0001). Overall, 34 pedicle screws were inserted (AR, 18; IMFR, 16). Final screw placement was comparable using both techniques ( p = 0.58). Lateral screws violations were observed in four IMFR screws (1 to 2 mm) as compared with five in AR group (2 to 3 mm). Reregistration after moving RF to C2 was possible using surface screws in IMFR group, thus avoiding new 3-D image acquisition.

Conclusion

During intraoperative 3-D navigation in spine procedures, surface fiducial registration using IMF provided superior accuracy over automated registration. It allowed repeat registration without repeating radiation during long spine segment instrumentations. More studies are needed to clarify both practical and clinical application of this method.
Maxillary Sinus Mucocele as a Late Complication in Zygomatic-Orbital Complex Fracture
Authors: da Silva de Menezes Juliana Dreyer , Moura LucasBorin , Pereira-Filho ValfridoAntonio , Hochuli-Vieira Eduardo
Published: April 2016

This article presents an unusual case of maxillary sinus mucocele as a late complication of zygomatic-orbital complex fracture, 23 years after the initial treatment. The patient was referring diplopia and decreased visual acuity with signs of dystopia, proptosis, and epiphora. Computed tomographic scan revealed an expansive lesion in the maxillary sinus with surrounding bone erosion and displacement of the eyeball. Treatment option was excisional biopsy and orbital floor reconstruction with titanium mesh restoring the appropriate orbital position. We propose that in the case of postoperative ophthalmological sequelae of facial fractures involving paranasal sinuses, mucocele should be considered in the differential diagnosis.
Complications after Fusion for Thoracolumbar Fractures in Patients with Ankylosing Spondylitis
Authors: Puvanesarajah Varun , Cancienne Jourdan M. , Shimer Adam L. , Shen Francis H. , Hassanzadeh Hamid
Published: April 2016

Study Design

Retrospective analysis of a Medicare database (2005 to 2012).

Objective

To study postoperative complication rates following thoracolumbar fusion for traumatic thoracolumbar fracture in patients with ankylosing spondylitis (AS) compared with patients without AS.

Methods

The PearlDiver database (2005 to 2012) was queried to examine postoperative complication rates in patients with AS undergoing posterior thoracolumbar fusion for thoracolumbar fracture ( n  =  968). Complication rates were compared with proportion-matched controls without AS undergoing the same procedure ( n  =  1,979). We examined and compared the incidence of death, postoperative infection, transfusion, venous thromboembolism, respiratory failure, pneumonia, myocardial infarction, urinary tract infection, and acute renal failure in each cohort within 90 days postoperatively.

Results

Patients with AS had significantly higher rates of surgical site infection (odds ratio [OR] 1.6, 95% confidence interval [CI] 1.2 to 2.2, p  =  0.002), day-of-surgery transfusion rates (OR 1.5, 95% CI 1.3 to 1.8, p < 0.0001), respiratory failure (OR 1.8, 95% CI 1.3 to 2.5, p  =  0.0006), pneumonia (OR 1.8, 95% CI 1.3 to 2.5, p  =  0.0002), acute renal failure (OR 1.6, 95% CI 1.2 to 2.3, p  =  0.005), and total medical complications (OR 1.5, 95% CI 1.2 to 1.9, p < 0.0001). Ninety-day mortality was not different between the two cohorts ( p  =  0.18).

Conclusions

Thoracolumbar fusion for thoracolumbar fracture in patients with AS is associated with increased rates of surgical site infection, transfusion, respiratory failure, pneumonia, and acute renal failure postoperatively compared with patients without AS. The level of evidence in this study was III.
Tuning dissociation using isoelectronically doped graphene and hexagonal boron nitride: Water and other small molecules
Authors: Al-Hamdani Yasmine S. , Alfè Dario , von Lilienfeld O. Anatole , Michaelides Angelos
Published: April 2016

Novel uses for 2-dimensional materials like graphene and hexagonal boron nitride (h-BN) are being frequently discovered especially for membrane and catalysis applications. Still however, a great deal remains to be understood about the interaction of environmentally and industrially relevant molecules such as water with these materials. Taking inspiration from advances in hybridising graphene and h-BN, we explore using density functional theory, the dissociation of water, hydrogen, methane, and methanol on graphene, h-BN, and their isoelectronic doped counterparts: BN doped graphene and C doped h-BN. We find that doped surfaces are considerably more reactive than their pristine counterparts and by comparing the reactivity of several small molecules, we develop a general framework for dissociative adsorption. From this a particularly attractive consequence of isoelectronic doping emerges: substrates can be doped to enhance their reactivity specifically towards either polar or non-polar adsorbates. As such, these substrates are potentially viable candidates for selective catalysts and membranes, with the implication that a range of tuneable materials can be designed.
On effective temperature in network models of collective behavior
Authors: Porfiri Maurizio , Ariel Gil
Published: April 2016

Collective behavior of self-propelled units is studied analytically within the Vectorial Network Model (VNM), a mean-field approximation of the well-known Vicsek model. We propose a dynamical systems framework to study the stochastic dynamics of the VNM in the presence of general additive noise. We establish that a single parameter, which is a linear function of the circular mean of the noise, controls the macroscopic phase of the system—ordered or disordered. By establishing a fluctuation–dissipation relation, we posit that this parameter can be regarded as an effective temperature of collective behavior. The exact critical temperature is obtained analytically for systems with small connectivity, equivalent to low-density ensembles of self-propelled units. Numerical simulations are conducted to demonstrate the applicability of this new notion of effective temperature to the Vicsek model. The identification of an effective temperature of collective behavior is an important step toward understanding order–disorder phase transitions, informing consistent coarse-graining techniques and explaining the physics underlying the emergence of collective phenomena.
An assessment of mean-field mixed semiclassical approaches: Equilibrium populations and algorithm stability
Authors: Bellonzi Nicole , Jain Amber , Subotnik Joseph E.
Published: April 2016

We study several recent mean-field semiclassical dynamics methods, focusing on the ability to recover detailed balance for long time (equilibrium) populations. We focus especially on Miller and Cotton’s [J. Phys. Chem. A 117, 7190 (2013)] suggestion to include both zero point electronic energy and windowing on top of Ehrenfest dynamics. We investigate three regimes: harmonic surfaces with weak electronic coupling, harmonic surfaces with strong electronic coupling, and anharmonic surfaces with weak electronic coupling. In most cases, recent additions to Ehrenfest dynamics are a strong improvement upon mean-field theory. However, for methods that include zero point electronic energy, we show that anharmonic potential energy surfaces often lead to numerical instabilities, as caused by negative populations and forces. We also show that, though the effect of negative forces can appear hidden in harmonic systems, the resulting equilibrium limits do remain dependent on any windowing and zero point energy parameters.
Time resolved interferometric study of the plasma plume induced shock wave in confined geometry: Two-dimensional mapping of the ambient and plasma density
Authors: Choudhury Kaushik , Singh R. K. , Narayan Surya , Srivastava Atul , Kumar Ajai
Published: April 2016

An experimental investigation of the laser produced plasma induced shock wave in the presence of confining walls placed along the axial as well as the lateral direction has been performed. A time resolved Mach Zehnder interferometer is set up to track the primary as well as the reflected shock waves and its effect on the evolving plasma plume has been studied. An attempt has been made to discriminate the electronic and medium density contributions towards the changes in the refractive index of the medium. Two dimensional spatial distributions for both ambient medium density and plasma density (electron density) have been obtained by employing customised inversion technique and algorithm on the recorded interferograms. The observed density pattern of the surrounding medium in the presence of confining walls is correlated with the reflected shock wave propagation in the medium. Further, the shock wave plasma interaction and the subsequent changes in the shape and density of the plasma plume in confined geometry are briefly described.
Experimental study of unsteady aerothermodynamic phenomena on shock-tube wall using fast-response temperature-sensitive paints
Authors: Ozawa Hiroshi
Published: April 2016

This paper describes an experimental study that used a fast-response temperature-sensitive paint (TSP) to investigate the unsteady aerothermodynamic phenomena occurring on a shock-tube wall. To understand these phenomena in detail, a fast-response TSP with high temperature sensitivity developed for transient temperature measurement was applied to the wall. The shock-tube experiment was carried out under the over-tailored condition, with a pressure ratio of 110 for test gases of air in driver/driven tubes. The following aspects were clarified using the TSP: (a) the TSP could be used to visualize the unsteady aerothermodynamic phenomena and estimate the quantitative heat flux on the shock-tube wall; (b) an x-t diagram based on the TSP response showed shock-tube wall characteristics that included the incident/reflected shocks, laminar-to-turbulent boundary-layer transition, streaks in the turbulent boundary layer, reflected shock/turbulent boundary layer interaction, and waves reflected from a contact surface; (c) the TSP graphically showed that a transition front from the plate’s leading edge and turbulent spots moved with 80% of the free-stream velocity behind the incident shock. In addition, the TSP could track the growth of the turbulent spots on the wall.
Electron energy loss spectroscopy of excitons in two-dimensional-semiconductors as a function of temperature
Authors: Tizei Luiz H. G. , Lin Yung-Chang , Lu Ang-Yu , Li Lain-Jong , Suenaga Kazu
Published: April 2016

We have explored the benefits of performing monochromated Electron Energy Loss Spectroscopy (EELS) in samples at cryogenic temperatures. As an example, we have observed the excitonic absorption peaks in single layer Transition Metal Dichalcogenides. These peaks appear separated by small energies due to spin orbit coupling. We have been able to distinguish the split for MoS2 below 300 K and for MoSe2 below 220 K. However, the distinction between peaks is only clear at 150 K. We have measured the change in absorption threshold between 150 K and 770 K for MoS2 and MoSe2. We discuss the effect of carbon and ice contamination in EELS spectra. The increased spectral resolution available made possible with modern monochromators in electron microscopes will require the development of stable sample holders which reaches temperatures far below that of liquid nitrogen.
Development of broadband X-ray interference lithography large area exposure system
Authors: Xue Chaofan , Wu Yanqing , Zhu Fangyuan , Yang Shumin , Liu Haigang , Zhao Jun , Wang Liansheng , Tai Renzhong
Published: April 2016

The single-exposure patterned area is about several 102 × 102 μm2 which is mainly decided by the mask area in multi-beam X-ray interference lithography (XIL). The exposure area is difficult to stitch to a larger one because the patterned area is surrounded by 0th diffraction exposure areas. To block the 0th diffraction beams precisely and effectively, a new large area exposure technology is developed in the Shanghai Synchrotron Radiation Facility by applying an order-sorting aperture with a new in situ monitoring scheme in the XIL system. The patterned area could be stitched readily up to several square centimeters and even bigger by this technology.
Existence of global solutions for a chemotaxis-fluid system with nonlinear diffusion
Authors: Chung Yun-Sung , Kang Kyungkeun
Published: April 2016

We consider a coupled system consisting of the Navier-Stokes equations and a porous medium type of Keller-Segel system that model the motion of swimming bacteria living in fluid and consuming oxygen. We establish the global-in-time existence of weak solutions for the Cauchy problem of the system in dimension three. In addition, if the Stokes system, instead Navier-Stokes system, is considered for the fluid equation, we prove that bounded weak solutions exist globally in time.
Dust on a surface in a plasma: A charge simulation
Authors: Heijmans L. C. J. , Nijdam S.
Published: April 2016

An electrically isolated particle on a substrate surface will be electrically charged when a plasma is applied above it. We show that the magnitude of this charge is determined by a balance of the impeding ion and electron fluxes that are strongly influenced by the nearby substrate. By simulating this process, we find that the charge density of the particle can be much higher than that of the substrate. This is due to the height of the particle, which causes additional electron collection.
Non-contact online thickness measurement system for metal films based on eddy current sensing with distance tracking technique
Authors: Li Wei , Wang Hongbo , Feng Zhihua
Published: April 2016

This paper proposes an online, non-contact metal film thickness measurement system based on eddy current sensing. The slope of the lift-off curve (LOC) is used for characterizing target thickness. Theoretical derivation was conducted to prove that the slope is independent of the lift-off variation. In practice, the measurement has some immunity to the lift-off, but not perfect. The slope of LOC is still affected at some extent by the lift-off. Hence, a height tracking system was also proposed, which could stabilize the distance between the sensor and the target and significantly reduce the lift-off effect. The height tracking system contains a specially designed probe, which could vibrate rapidly to obtain a fast measurement speed, and its height can be adjusted up and down continuously to stabilize the lift-off. The sensor coil in the thickness measurement system was also used as the height sensor in the height tracking system. Several experiments were conducted to test the system performances under static and dynamic conditions. This measurement system demonstrated significant advantages, such as simple and clear conversion between the slope of LOC and target thickness, high resolution and stability, and minimized effect of lift-off variation.
Microscopic thin film optical anisotropy imaging at the solid-liquid interface
Authors: Miranda Adelaide , De Beule Pieter A. A.
Published: April 2016

Optical anisotropy of thin films has been widely investigated through ellipsometry, whereby typically an optical signal is averaged over a ∼1 cm2 elliptical area that extends with increasing angle-of-incidence (AOI). Here, we report on spectroscopic imaging ellipsometry at the solid-liquid interface applied to a supported lipid bilayer (SLB). We detail how a differential spectrally resolved ellipsometry measurement, between samples with and without optically anisotropic thin film on an absorbing substrate, can be applied to recover in and out of plane refractive indices of the thin film with known film thickness, hence determining the thin film optical anisotropy. We also present how optimal wavelength and AOI settings can be determined ensuring low parameter cross correlation between the refractive indices to be determined from a differential measurement in Δ ellipsometry angle. Furthermore, we detail a Monte Carlo type analysis that allows one to determine the minimal required optical ellipsometry resolution to recover a given thin film anisotropy. We conclude by presenting a new setup for a spectroscopic imaging ellipsometry based on fiber supercontinuum laser technology, multi-wavelength diode system, and an improved liquid cell design, delivering a 5 ×–10 × ellipsometric noise reduction over state-of-the-art. We attribute this improvement to increased ellipsometer illumination power and a reduced light path in liquid through the use of a water dipping objective.
Point contacts at the copper-indium-gallium-selenide interface—A theoretical outlook
Authors: Bercegol Adrien , Chacko Binoy , Klenk Reiner , Lauermann Iver , Lux-Steiner Martha Ch. , Liero Matthias
Published: April 2016

For a long time, it has been assumed that recombination in the space-charge region of copper-indium-gallium-selenide (CIGS) is dominant, at least in high efficiency solar cells with low band gap. The recent developments like potassium fluoride post deposition treatment and point-contact junction may call this into question. In this work, a theoretical outlook is made using three-dimensional simulations to investigate the effect of point-contact openings through a passivation layer on CIGS solar cell performance. A large set of solar cells is modeled under different scenarios for the charged defect levels and density, radius of the openings, interface quality, and conduction band offset. The positive surface charge created by the passivation layer induces band bending and this influences the contact (CdS) properties, making it beneficial for the open circuit voltage and efficiency, and the effect is even more pronounced when coverage area is more than 95%, and also makes a positive impact on the device performance, even in the presence of a spike at CIGS/CdS heterojunction.
Shock induced damage in copper: A before and after, three-dimensional study
Authors: Menasche David B. , Lind Jonathan , Li Shiu Fai , Kenesei Peter , Bingert John F. , Lienert Ulrich , Suter Robert M.
Published: April 2016

We report on the microstructural features associated with the formation of incipient spall and damage in a fully recrystallized, high purity copper sample. Before and after ballistic shock loading, approximately 0.8 mm3 of the sample's crystal lattice orientation field is mapped using non-destructive near-field High Energy Diffraction Microscopy. Absorption contrast tomography is used to image voids after loading. This non-destructive interrogation of damage initiation allows for novel characterization of spall points vis-a-vis microstructural features and a fully 3D examination of microstructural topology and its influence on incipient damage. The spalled region is registered with and mapped back onto the pre-shock orientation field. As expected, the great majority of voids occur at grain boundaries and higher order microstructural features; however, we find no statistical preference for particular grain boundary types. The damaged region contains a large volume of Σ–3 (60°〈111〉) connected domains with a large area fraction of incoherent Σ-3 boundaries.
Epidemic spreading with activity-driven awareness diffusion on multiplex network
Authors: Guo Quantong , Lei Yanjun , Jiang Xin , Ma Yifang , Huo Guanying , Zheng Zhiming
Published: April 2016

There has been growing interest in exploring the interplay between epidemic spreading with human response, since it is natural for people to take various measures when they become aware of epidemics. As a proper way to describe the multiple connections among people in reality, multiplex network, a set of nodes interacting through multiple sets of edges, has attracted much attention. In this paper, to explore the coupled dynamical processes, a multiplex network with two layers is built. Specifically, the information spreading layer is a time varying network generated by the activity driven model, while the contagion layer is a static network. We extend the microscopic Markov chain approach to derive the epidemic threshold of the model. Compared with extensive Monte Carlo simulations, the method shows high accuracy for the prediction of the epidemic threshold. Besides, taking different spreading models of awareness into consideration, we explored the interplay between epidemic spreading with awareness spreading. The results show that the awareness spreading can not only enhance the epidemic threshold but also reduce the prevalence of epidemics. When the spreading of awareness is defined as susceptible-infected-susceptible model, there exists a critical value where the dynamical process on the awareness layer can control the onset of epidemics; while if it is a threshold model, the epidemic threshold emerges an abrupt transition with the local awareness ratio α approximating 0.5. Moreover, we also find that temporal changes in the topology hinder the spread of awareness which directly affect the epidemic threshold, especially when the awareness layer is threshold model. Given that the threshold model is a widely used model for social contagion, this is an important and meaningful result. Our results could also lead to interesting future research about the different time-scales of structural changes in multiplex networks.
Room temperature, very sensitive thermometer using a doubly clamped microelectromechanical beam resonator for bolometer applications
Authors: Zhang Y. , Watanabe Y. , Hosono S. , Nagai N. , Hirakawa K.
Published: April 2016

We propose a room temperature, all electrical driving and detecting, very sensitive thermometer structure using a microelectromechanical (MEMS) resonator for bolometer applications. We have fabricated a GaAs doubly clamped MEMS beam resonator whose oscillation can be excited and detected by the piezoelectric effect. When a heating power is applied to a NiCr film deposited on the MEMS beam surface, internal thermal stress is generated in the beam, leading to a reduction in the resonance frequency. The present device detects the shift in the resonance frequency caused by heating and works as a very sensitive thermometer. When the resonator was driven by a voltage slightly below the threshold for the nonlinear, hysteretic oscillation, the thermometer showed a voltage responsivity of about 3300 V/W, while keeping a low noise spectral density of about 60 nV/Hz1/2, demonstrating a noise equivalent power of <20 pW/Hz1/2 even at room temperature. The observed effect can be used for realizing high-sensitivity terahertz bolometers for room-temperature operation.
Theory of intraband plasmons in doped carbon nanotubes: Rolled surface-plasmons of graphene
Authors: Sasaki Ken-ichi , Murakami Shuichi , Yamamoto Hideki
Published: April 2016

A single-wall carbon nanotube possesses two different types of plasmons specified by the wavenumbers in the azimuthal and axial directions. The azimuthal plasmon that is caused by interband transitions has been studied, while the effect of charge doping is unknown. In this paper, we show that when nanotubes are heavily doped, intraband transitions cause the azimuthal plasmons to appear as a plasmon resonance in the near-infrared region of the absorption spectra, which is absent for light doping due to the screening effect. The axial plasmons that are inherent in the cylindrical waveguide structures of nanotubes account for the absorption peak of the metallic nanotube observed in the terahertz region. The excitation of axial (azimuthal) plasmons requires a linearly polarized light parallel (perpendicular) to the tube's axis.
Communication: Influence of nanophase segregation on ion transport in room temperature ionic liquids
Authors: Griffin Philip J. , Wang Yangyang , Holt Adam P. , Sokolov Alexei P.
Published: April 2016

We report measurements of the ionic conductivity, shear viscosity, and structural dynamics in a homologous series of quaternary ammonium ionic liquids (ILs) and a prototypical imidazolium-based IL over a wide range of temperatures down to the glass transition. We find that the ionic conductivity of these materials generally decreases, while the shear viscosity correspondingly increases, with increasing volume fraction of aliphatic side groups. Upon crossing an aliphatic volume fraction of ∼0.40, we observe a sharp, order-of-magnitude decrease in ionic conductivity and enhancement of viscosity, which coincides with the presence of long-lived, nanometer-sized alkyl aggregates. These strong changes in dynamics are not mirrored in the ionicity of these ILs, which decreases nearly linearly with aliphatic volume fraction. Our results demonstrate that nanophase segregation in neat ILs strongly reduces ionic conductivity primarily due to an aggregation-induced suppression of dynamics.