bluuebunny/crossref_metadata_2025_split huggingface dataset:
Gold Nanoplate‐Enhanced Chemiluminescence and Macromolecular Shielding for Rapid Microbial Diagnostics
Authors: Bui Minh‐Phuong Ngoc , Brockgreitens John , Abbas Abdennour 
Published: April 2018

AbstractWith the global rise of antimicrobial resistance, rapid screening and identification of low concentrations of microorganisms in less than 1 h becomes an urgent technological need for evidence‐based antibiotic therapy. Although many commercially available techniques are labeled for rapid microbial detection, they often require 24–48 h of cell enrichment to reach detectable levels. Here, it is shown that the widely used reducing agent tris(2‐carboxyethyl)phosphine (TCEP) can also act as a powerful oxidant on gold nanoplates and subsequently lead to a strong catalysis of luminol chemiluminescence. The catalytic reaction results in up to 100‐fold signal enhancement and unprecedented stable luminescence for up to 10 min. However, when TCEP is exposed to microorganisms, it is oxidized by the microbial surface proteins and loses its catalytic properties, leading to a decrease in chemiluminescence. The competitive interaction of TCEP with Au nanoplates and microorganisms is used to introduce a homogenous rapid detection method that allows microbial screening in less than 10 min with a limit of detection down to 100 cfu mL−1. Furthermore, the concept of microbial macromolecular shielding using antibody‐conjugated polymers is introduced. The combination of TCEP redox activity and macromolecular shielding enables specific microbial identification within 1 h, without preconcentration, cell enrichment, or heavy equipment other than a hand‐held luminometer. The technique is demonstrated by specific detection of methicillin‐resistant Staphylococcus aureus in environmental and urine samples containing a mixture of microorganisms.
Impact of the NO Anneal on the Microscopic Structure and Chemical Composition of the Si‐Face 4H‐SiC/SiO2 Interface
Authors: Gruber Gernot , Gspan Christian , Fisslthaler Evelin , Dienstleder Martina , Pobegen Gregor , Aichinger Thomas , Meszaros Robert , Grogger Werner , Hadley Peter 
Published: April 2018

AbstractUnderstanding the microscopic structure of the SiC/SiO2 interface is crucial for the improvement of SiC based metal‐oxide‐semiconductor field‐effect transistors (MOSFETs). It is well established that interface states degrade the performance and reliability of SiC MOSFETs and that passivation can be achieved by anneals in NO‐containing atmospheres. However, the structural changes associated with the NO anneal and the improvement of the channel electron mobility are still not fully understood. In this study, the SiC/SiO2 interface of the state‐of‐the art 4H‐SiC n‐channel MOSFETs with a deposited oxide is extensively investigated with advanced scanning transmission electron microscopy (STEM) and spatially resolved electron energy‐loss spectroscopy (EELS) methods. The samples are treated with different postoxidation anneals (NO vs O2), resulting in strongly differing mobility and point defect density. The most notable structural difference between the samples is an increased N concentration located in the transition region between the SiC and the SiO2 of the NO‐annealed sample. The N signal is evenly distributed along the whole faceted interface and has a half‐width of wN = (1.8 ± 0.7) nm and an estimated areal density of cN = (4 ± 1) × 1014 cm−2. The observations support the idea that the N incorporation happens predominantly directly at the SiC/SiO2 interface where defect states are passivated.
Folding of Nanoparticle Chains into 2D Arrays: Structural Change of DNA‐Functionalized Gold Nanoparticle Assemblies
Authors: Shiraishi Shota , Yu Li , Akiyama Yoshitsugu , Wang Guoqing , Kikitsu Tomoka , Miyamura Kazuo , Takarada Tohuru , Maeda Mizuo 
Published: April 2018

AbstractNanoparticle (NP) arrays exhibit collective physical and chemical properties, which are potentially applicable to various nanodevices, such as data storage media and biosensors. In this Communication, a spontaneous method of constructing the 2D NP arrays from precursory 1D chains of DNA‐modified NPs is described. The single‐stranded (ss) DNA‐modified gold NPs are hybridized to a long repetitive ssDNA synthesized with rolling circle amplification to produce the precursory NP chains. Transmission electron microscopy reveals that the chains of fully matched double‐stranded (ds) DNA‐modified NPs undergo shrinkage and folding during evaporation to afford the 2D NP arrays. In particular, the chains of long dsDNA‐modified NPs with short interparticle spacing form the NP arrays with anisotropic interparticle spacing. The present approach could be useful for readily aligning NPs on the substrate surface.
White‐Light Generation through Nonlinear Optical Response of 1,3,5,7‐Tetraphenyladamantane: Amorphous versus Crystalline States
Authors: Rosemann Nils W. , Locke Harald , Schreiner Peter R. , Chatterjee Sangam 
Published: April 2018

AbstractThe vast optical nonlinearity of 1,3,5,7‐tetraphenyladamantane (AdPh4) enables efficient frequency conversion. The observed spectrum depends heavily on the material's habitus. In particular, it shows nonlinear white‐light generation when its powder form is irradiated in the near‐infrared, similar to an analogous organotin sulfide cluster [(PhSn)4S6]. In contrast, single crystals of AdPh4 exclusively exhibit narrow‐band second‐harmonic generation, i.e., discrete conversion within the crystal, rather than spectrally broadband white‐light emission. This shows that crystallinity restricts the nonlinear response to the symmetry‐allowed higher‐harmonics, in this case the even‐numbered, second harmonic, and inhibits the quasi‐continuum white‐light emission. Using the diamondoid‐based material significantly enhances compatibility with conventional production techniques using photorefractive polymers and is thus an important step towards the fabrication of all‐integrated white‐light emitting devices.
Modulation of the Optical Properties of Lithium Manganese Oxide via Li‐Ion De/Intercalation
Authors: Joshi Yug , Hadjixenophontos Efi , Nowak Susann , Lawitzki Robert , Ghosh Prakriti K. , Schmitz Guido 
Published: April 2018

AbstractThe optical response of lithium manganese oxide (LiMn2O4, LMO) on intercalation with Li ions is quantitatively characterized. For this purpose, a layer of LMO and a layer of platinum, acting as current collector/reflector, are deposited on oxidized silicon wafers. The active layer is structurally characterized using X‐ray diffractogram and transmission electron microscopy. Well‐defined intercalation states are prepared electrochemically and investigated by optical spectrometry in reflectance geometry. The measured dispersion curves are described by the Clausius–Mossotti dispersion equation to derive the complex refractive index as a function of wavelength and intercalation state. The observed variation of the effective resonant wavelength is consistent with the change in the band structure of LMO with lithium intercalation. Furthermore, the electrochromic reversibility is demonstrated in situ during the electrochemical reaction. From the calculations, a 1350 nm thick layer of LMO is sufficient to cause a phase shift of π at a wavelength of 750 nm, which indicates the material as a promising candidate to perform reliable optical switching.
Monocharged Electret Generator for Wearable Energy Harvesting Applications
Authors: Gong Shaobo , Wang Chenchen , Zhang Jinxi , Zhang Chi , West James E. , Ren Kailiang 
Published: April 2018

AbstractPolytetrafluoroethylene (PTFE)‐based electret materials have emerged as one of the most widely used materials in underwater transducer, microphone, and transistor applications. In this paper, it is shown for the first time that a monocharged (single type, electron) PTFE electret material can be used in energy harvesting and self‐powered device applications, such as wristband and shoe insole devices. At first, a theory based on the electrostatic effect is derived for the first time for monocharged electret generator (MCEG). For a hand‐shaking movement, the MCEG‐based wristband device can generate an output voltage and current of 14 V and 0.65 µA, respectively. Furthermore, it is found that the MCEG‐based shoe insole device can generate a maximum output voltage of 178 V and a current of 2.85 µA during walking. The maximum harvested power obtained is ≈35.63 µW in shoe insole‐based devices under a resistor load. Additionally, the power generated from the shoe insole device can light up 55 light‐emitting diodes with a single step of walking. Because of the relatively large output power density, ease of fabrication, and chemical stability, this device shows great promise for wearable self‐powered device applications.
Recent Progress in the Theoretical Investigation of Electrocatalytic Reduction of CO2
Authors: Tian Ziqi , Priest Chad , Chen Liang 
Published: April 2018

AbstractThe worldwide combustion of fossils produces anthropogenic CO2, which has deleterious effects on global climate patterns. An ideal solution is to develop high‐performance CO2 capture and utilization technologies that can convert CO2 into commercial products by means of electrocatalytic reduction with renewable energy. The design of electrocatalysts can be facilitated by accurate computational simulations based on density functional theory (DFT). Herein, commonly used models, from the computational hydrogen electrode model with constant charge assumption, to the explicit and implicit solvation model under constant potential condition, are reviewed. Thereafter, the applications of recent data‐driven methods, such as neutral network and machine learning, are introduced. Also, based on DFT calculations, four composition based classes of electrodes are further discussed, including (1) bulk metals and alloys, (2) nanoparticles, (3) metal‐nonmetal compounds and (4) carbon‐based materials. In this Review, several theoretical investigations which have been realized in practice are highlighted in particular, such as metal‐hydride nanocluster and carbon nitride supported copper complex for high‐efficiency CO2 reduction. It shows that the theoretical study can not only explain experimental phenomena but also predict improved candidates.
Prognostic factors after ultrasound‐guided percutaneous ablation of colorectal liver metastases: A systematic review
Authors: Klubien Jeanett , Kohl Andreas P. , Nolsøe Christian P. , Rosenberg Jacob , Pommergaard Hans‐Christian 
Published: April 2018

AbstractIntroductionLiver metastases from colorectal cancer are common and ablation therapy is a favourable treatment option for selected patients not suited for surgical resection. This study aimed to systematically review the literature and present prognostic factors associated with survival and local recurrence after percutaneous ultrasound‐guided ablation treatment.Materials and methodsThis review is reported according to the PRISMA. PubMed, Embase and Scopus were searched and records were independently screened by two authors, initially on title and abstract and subsequently on full‐text basis. The quality of the studies was assessed using the Newcastle‐Ottawa quality assessment scale.ResultsOf 2.882 records screened, 18 studies were included. The median survival was 23 months. One‐year survival was median 95% and 3‐year survival was median 58%. Complete ablation response and adjuvant chemotherapy produce considerably improved survival and low local recurrence rate outcomes.ConclusionPercutaneous ultrasound‐guided ablation technique for colorectal liver metastases provides impressive survival rates for patients not suited for surgical resection. However, there are some factors related to poorer prognosis, which may be considered when selecting patients.
A W‐Shaped Ga‐Dy‐Dy‐Dy‐Ga Cluster: Synthesis, Characterization, and Magnetic Properties
Authors: Peng Yan , Anson Christopher E. , Powell Annie K. 
Published: April 2018

AbstractA W‐shaped {Ga‐Dy‐Dy‐Dy‐Ga} coordination cluster, [Ga2Dy3(L)6(MeO)2(MeOH)3]⋅NO3⋅7 MeOH (1) with H2L, (E)‐2‐(2‐hydroxy‐3‐methoxy‐benzylideneamino)phenol was synthesized, characterized, and the magnetic properties investigated. The magnetic measurements indicate that the compound shows single‐molecule magnet (SMM) behavior under zero dc field. This suggests that the combination of GaIII ions and DyIII ions (4 f) is a successful strategy to assemble SMM clusters. The combination of these metal ions also offers prospects in dual functionality therapeutics for medical applications.
Optimization of Hexadentate Bispidine Ligands as Chelators for 64CuII PET Imaging
Authors: Comba Peter , Starke Miriam , Wadepohl Hubert 
Published: April 2018

AbstractThe coordination chemistry of the hexadentate bispidine ligand L1 with three pyridine, one pyridazine, and two tertiary amine donors with CuII and ZnII is reported. The substitution of one of the two cis‐disposed pyridine donors in‐plane with the two tertiary amines of the bispidine backbone by a pyridazine group was predicted to substantially reduce distortion from planarity of the tetradentate subunit and therefore was assumed to lead to higher CuII complex stability. The X‐ray single‐crystal structures of the ZnII and CuII complexes, which are in excellent agreement with the DFT‐ and MM‐optimized structures, confirmed this prediction but indicated that deviation from planarity is appreciable. This also emerges from solution spectroscopy (UV/Vis/NIR and EPR of the CuII complex), which indicated that the in‐plane ligand field is only slightly increased. The geometric parameters together with the lower basicity of pyridazine versus pyridine (pKa=2.33 vs. 5.23) are also in agreement with an only slightly more negative redox potential of the CuII/I couple (Eo=−780 vs. −760 mV, MeCN, vs. Fc/Fc+), and the potentiometrically determined CuII stability constant with L1 is slightly lower than that with the parent ligand L2 (log K=12.7 vs. 14.5). Therefore, modification of the donor groups is a more promising approach to increasing the stabilities of these complexes and yields 64CuII chelators that outperform known hexadentate bispidine ligands.
Brain gene expression analyses in virgin and mated queens of fire ants reveal mating‐independent and socially regulated changes
Authors: Calkins Travis L. , Chen Mei‐Er , Arora Arinder K. , Hawkings Chloe , Tamborindeguy Cecilia , Pietrantonio Patricia V. 
Published: April 2018

AbstractTranscriptomes of dissected brains from virgin alate and dealate mated queens from polygyne fire ants (Solenopsis invicta) were analyzed and compared. Thirteen genes were upregulated in mated queen brain, and nine were downregulated. While many of the regulated genes were either uncharacterized or noncodingRNAs, those annotated genes included two hexamerin proteins, astakine neuropeptide, serine proteases, and serine protease inhibitors. We found that for select differentially expressed genes in the brain, changes in gene expression were most likely driven by the changes in physiological state (i.e., age, nutritional status, or dominance rank) or in social environment (released from influence of primer pheromone). This was concluded because virgins that dealated after being separated from mated queens showed similar patterns of gene expression in the brain as those of mated queens forhexamerin 1,astakine, andXR_850909.Abaecin(XR_850725), however, appears upregulated only after mating. Therefore, our findings contribute to distinguish how specific gene networks, especially those influenced by queen primer pheromone, are regulated in queen ants. Additionally, to identify brain signaling pathways, we mined the fire ant genome and compiled a list of G‐protein‐coupled receptors (GPCRs). The expression level ofGPCRs and other genes in the “genetic toolkit” in the brains of virgin alates and mated dealate queens is reported.
Inference for a geometric‐poisson‐Rayleigh distribution under progressive‐stress accelerated life tests based on type‐I progressive hybrid censoring with binomial removals
Authors: Nadarajah Saralees , Abdel‐Hamid Alaa H. , Hashem Atef F. 
Published: April 2018

AbstractBased on failures of a parallel‐series system, a new distribution called geometric‐Poisson‐Rayleigh distribution is proposed. Some properties of the distribution are discussed. A real data set is used to compare the new distribution with other 6 distributions. The progressive‐stress accelerated life tests are considered when the lifetime of an item under use condition is assumed to follow the geometric‐Poisson‐Rayleigh distribution. It is assumed that the scale parameter of the geometric‐Poisson‐Rayleigh distribution satisfies the inverse power law such that the stress is a nonlinear increasing function of time and the cumulative exposure model for the effect of changing stress holds. Based on type‐I progressive hybrid censoring with binomial removals, the maximum likelihood and Bayes (using linear‐exponential and general entropy loss functions) estimation methods are considered to estimate the involved parameters. Some point predictors such as the maximum likelihood, conditional median, best unbiased, and Bayes point predictors for future order statistics are obtained. The Bayes estimates are obtained using Markov chain Monte Carlo algorithm. Finally, a simulation study is performed, and numerical computations are performed to compare the performance of the implemented methods of estimation and prediction.
Multilayer Graphene–GeSn Quantum Well Heterostructure SWIR Light Source
Authors: Cong Hui , Yang Fan , Xue Chunlai , Yu Kai , Zhou Lin , Wang Nan , Cheng Buwen , Wang Qiming 
Published: April 2018

AbstractThe problem of light source always prevents silicon‐based photonics from achieving a final integration. Although some optical pump lasers have been reported in recent years, an electrical pumping laser is considered as the ultimate solution. To fabricate a Si‐based laser, there are some crucial obstacles that need to be solved such as difficulties in material epitaxy, light absorption by metal electrodes, and compatibility with the existing complementary metal–oxide–semiconductor transistor process. Here, a multilayer graphene and GeSn/Ge quantum well (QW) heterostructure is designed and fabricated as a Si‐based light source. Specially designed Ge0.9Sn0.1/Ge QWs are used as active layer, which achieves a photoluminescence (PL) peak at 2050 nm. Graphene, which has a high transmittance for all bands of light, lessens the burden of growing thick cladding layer and perfectly breaks the deadlock of light disappearance in metal contacts. The electroluminescence (EL) spectrum of the device is achieved at a peak of 2100 nm under an injection current density of 100 A cm−2. Both the PL and EL measurements show the heterostructure has good performance as a short‐wave infrared (SWIR) light source. Therefore, the results provides a good alternative for the light source in silicon‐based photonics.
Vertical ZnO Nanotube Transistor on a Graphene Film for Flexible Inorganic Electronics
Authors: Oh Hongseok , Park JunBeom , Choi Woojin , Kim Heehun , Tchoe Youngbin , Agrawal Arpana , Yi Gyu‐Chul 
Published: April 2018

AbstractThe bottom‐up integration of a 1D–2D hybrid semiconductor nanostructure into a vertical field‐effect transistor (VFET) for use in flexible inorganic electronics is reported. Zinc oxide (ZnO) nanotubes on graphene film is used as an example. The VFET is fabricated by growing position‐ and dimension‐controlled single crystal ZnO nanotubes vertically on a large graphene film. The graphene film, which acts as the substrate, provides a bottom electrical contact to the nanotubes. Due to the high quality of the single crystal ZnO nanotubes and the unique 1D device structure, the fabricated VFET exhibits excellent electrical characteristics. For example, it has a small subthreshold swing of 110 mV dec−1, a high Imax/Imin ratio of 106, and a transconductance of 170 nS µm−1. The electrical characteristics of the nanotube VFETs are validated using 3D transport simulations. Furthermore, the nanotube VFETs fabricated on graphene films can be easily transferred onto flexible plastic substrates. The resulting components are reliable, exhibit high performance, and do not degrade significantly during testing.
Ultrasound‐assisted low‐density‐solvent‐based solvent‐demulsified dispersive liquid–liquid microextraction for the quantification of amino acids in biological samples
Authors: Zare Fahimeh , Razmi Mahdi 
Published: April 2018

AbstractAn ultrasound‐assisted low‐density‐solvent‐based solvent‐demulsified dispersive liquid–liquid microextraction followed by high‐performance liquid chromatography with ultraviolet detection method has been established for the purpose of microextraction and recognition of tyrosine, phenylalanine and tryptophan from plasma and urine samples. For the preconcentration of analytes, 10 mL of sample solution was placed in test tube. A blend of 200 μL 1‐dodecanol and 100 μL acetonitrile were quickly injected into the sample solution and then shaken for 4.8 min using ultrasonic irradiation. The addition of demulsifier into the formed emulsion results in rapid separation of the mixture into two phases. The central composite design was used for optimization of microextraction conditions. Under the optimized conditions, the calibration graphs of tyrosine, phenylalanine and tryptophan were linear in the range of 1–200 μmol L−1. Limits of detection and quantification were 0.17–0.32 and 0.64–1.09 μmol L−1, respectively. This procedure was successfully used to determine target analytes in spiked plasma and urine samples; the relative mean recoveries ranged from 84.7 to 96.4%.
Estudo mecânico das propriedades dos fios de sutura usados em cirurgias ortopédicas
Authors: Gomide Leandro Cardoso , Campos Dagoberto de Oliveira , Araújo Cleudmar Amaral , Menegaz Gabriela Lima , Cardoso Rafael Silva , Saad Júnior Sérgio Crosara 
Published: April 2018

Resumo
Objetivo Avaliar as propriedades mecânicas dos fios de sutura normalmente usados nas cirurgias ortopédicas e caracterizar seu comportamento por meio de ensaios de tração para verificar qual deles apresenta maior resistência mecânica.
Método Os ensaios de tração dos diferentes tipos de fios de sutura foram feitos na máquina de ensaios mecânicos BME 10 kN, com célula de carga de capacidade máxima de 50 kgf. Foram ensaiadas sete amostras de cada tipo de fio de sutura, foram fixadas cada uma das extremidades da amostra na garra metálica própria para o ensaio de fios e manteve-se o comprimento inicial de 5 cm. Os ensaios foram feitos com uma velocidade de 20 mm/minuto e à temperatura ambiente, registraram-se os dados de força máxima e o deslocamento máximo na ruptura dos fios.
Resultados A força média de ruptura mais elevada foi observada na sutura FiberWire® 2 (Artrhex, Naples, FL, EUA) (240,17 N), seguida pela HiFi® 2 (Conmed, Utica, NY, EUA) (213,39 N) e Ethibond® 5 (Ethicon Inc., Somerville, NJ, EUA) (207,38 N). A menor força média de ruptura foi obtida para o fio Ethibond® 2 (Ethicon Inc., Somerville, NJ, EUA) (97,8 N).
Conclusão Os fios de sutura não absorvíveis de polimistura trançada, de surgimento mais recente, são superiores ao fio de sutura convencional de poliéster trançado. O FiberWire® 2 é o mais resistente dos fios avaliados no presente estudo.