bluuebunny/crossref_metadata_2025 huggingface dataset:
Patterns in the skin microbiota differ in children and teenagers between rural and urban environments
Authors: Lehtimäki Jenni , Karkman Antti , Laatikainen Tiina , Paalanen Laura , von Hertzen Leena , Haahtela Tari , Hanski Ilkka , Ruokolainen Lasse
Published: March 2017

The composition of human microbiota is affected by a multitude of factors. Understanding the dynamics of our microbial communities is important for promoting human health because microbiota has a crucial role in the development of inflammatory diseases, such as allergies. We have studied the skin microbiota of both arms in 275 Finnish children of few months old to teenagers living in contrasting environments. We show that while age is a major factor affecting skin microbial composition, the living environment also discriminates the skin microbiota of rural and urban children. The effect of environment is age-specific; it is most prominent in toddlers but weaker for newborns and non-existent for teenagers. Within-individual variation is also related to age and environment. Surprisingly, variation between arms is smaller in rural subjects in all age groups, except in teenagers. We also collected serum samples from children for characterization of allergic sensitization and found a weak, but significant association between allergic sensitization and microbial composition. We suggest that physiological and behavioral changes, related to age and the amount of contact with environmental microbiota, jointly influence the dynamics of the skin microbiota, and explain why the association between the living environment skin microbiota is lost in teenager.
Sustained delivery of calcium and orthophosphate ions from amorphous calcium phosphate and poly(L-lactic acid)-based electrospinning nanofibrous scaffold
Authors: Niu Xufeng , Liu Zhongning , Tian Feng , Chen Siqian , Lei Lei , Jiang Ting , Feng Qingling , Fan Yubo
Published: March 2017

The purpose of this study is to investigate electrospinning poly(L-lactic acid) (PLLA) nanofibrous scaffold with different contents of amorphous calcium phosphate (ACP), which is suitable for using in bone regeneration through sustained release of calcium and orthophosphate ions. Three groups of nanofibrous scaffolds, ACP-free PLLA, ACP-5 wt%/PLLA and ACP-10 wt%/PLLA, are developed and characterized by scanning electron microscopy and gel permeation chromatography. Calcium and phosphate colorimetric assay kits are used to test ions released from scaffold during hydrolytic degradation. The results show ACP-5 wt%/PLLA and ACP-10 wt%/PLLA scaffolds have relatively high degradation rates than ACP-free PLLA group. The bioactivity evaluation further reveals that ACP-5 wt%/PLLA scaffold presents more biocompatible feature with pre-osteoblast cells and significant osteogenesis ability of calvarial bone defect. Due to the facile preparation method, sustained calcium and orthophosphate release behavior, and excellent osteogenesis capacity, the presented ACP/PLLA nanofibrous scaffold has potential applications in bone tissue engineering.
Enzyme-dependent fluorescence recovery of NADH after photobleaching to assess dehydrogenase activity of isolated perfused hearts
Authors: Moreno Angel , Kuzmiak-Glancy Sarah , Jaimes Rafael , Kay Matthew W.
Published: March 2017

Reduction of NAD+ by dehydrogenase enzymes to form NADH is a key component of cellular metabolism. In cellular preparations and isolated mitochondria suspensions, enzyme-dependent fluorescence recovery after photobleaching (ED-FRAP) of NADH has been shown to be an effective approach for measuring the rate of NADH production to assess dehydrogenase enzyme activity. Our objective was to demonstrate how dehydrogenase activity could be assessed within the myocardium of perfused hearts using NADH ED-FRAP. This was accomplished using a combination of high intensity UV pulses to photobleach epicardial NADH. Replenishment of epicardial NADH fluorescence was then imaged using low intensity UV illumination. NADH ED-FRAP parameters were optimized to deliver 23.8 mJ of photobleaching light energy at a pulse width of 6 msec and a duty cycle of 50%. These parameters provided repeatable measurements of NADH production rate during multiple metabolic perturbations, including changes in perfusate temperature, electromechanical uncoupling, and acute ischemia/reperfusion injury. NADH production rate was significantly higher in every perturbation where the energy demand was either higher or uncompromised. We also found that NADH production rate remained significantly impaired after 10 min of reperfusion after global ischemia. Overall, our results indicate that myocardial NADH ED-FRAP is a useful optical non-destructive approach for assessing dehydrogenase activity.
International incidence and mortality trends of liver cancer: a global profile
Authors: Wong Martin C. S. , Jiang Johnny Y. , Goggins William B , Liang Miaoyin , Fang Yuan , Fung Franklin D. H. , Leung Colette , Wang Harry H. X. , Wong Grace L. H. , Wong Vincent W.S. , Chan Henry L. Y.
Published: March 2017

We examined the global incidence and mortality rates of liver cancer, and evaluated the association between incidence/mortality and socioeconomic development (Human Development Index [HDI] and Gross Domestic Product [GDP]) using linear regression analysis. The average annual percent change (AAPC) of the trends was evaluated from join-point regression analysis. The global incidence of liver cancer varied widely by nine-fold, and was negatively correlated with HDI (men: r = −0.232, p = 0.003; women: r = −0.369, p < 0.001) and GDP per capita (men: r = −0.164, p = 0.036; women: r = −0.212, p = 0.007). Its mortality showed a similarly negative correlation with both indices. The greatest incidence rise in men was observed in Poland (AAPC = 17.5, 95% C.I. = 5.6, 30.9) and Brazil (AAPC = 13.2, 95% C.I. = 5.9, 21.0), whereas Germany (AAPC = 6.6, 95% C.I = 2.0, 11.5) and Norway (AAPC = 6.5, 95% C.I. = 3.2, 10.0) had the greatest increase in women. The mortality rates paralleled the incidence rates in most countries. For mortality, Malta (AAPC = 11.5, 95% C.I. = 3.9, 19.8), Australia (AAPC = 6.8, 95% C.I. = 2.2, 11.5) and Norway (APCC = 5.6, 95% C.I. = 2.8, 8.5) reported the biggest increase among men; whilst Australia (AAPC = 13.4, 95% C.I. = 7.8, 19.4) and Singapore (AAPC = 7.7, 95% C.I. = 4.1, 11.5) showed the most prominent rise among women. These epidemiological data identified countries with potentially increasing trends of liver cancer for preventive actions.
Development of a wash-free immunoassay using Escherichia coli cells with autodisplayed Z-domains
Authors: Pyun Jae-Chul , Jose Joachim , Park Min
Published: March 2017

Escherichia colicells that autodisplay Z-domains have been used to improve the sensitivity and limit of detection (LOD) of immunoassays by controlling antibody orientation.
Frequency-control of protein translocation across an oscillating nanopore
Authors: Cecconi Fabio , Shahzad Muhammad Adnan , Marini Bettolo Marconi Umberto , Vulpiani Angelo
Published: March 2017

The translocation of a lipid binding protein (LBP) is studied using a phenomenological coarse-grained computational model that simplifies both chain and pore geometry.
Raspberry ketone fails to reduce adiposity beyond decreasing food intake in C57BL/6 mice fed a high-fat diet
Authors: Cotten Bradley M. , Diamond Stephanie A. , Banh Taylor , Hsiao Yung-Hsuan , Cole Rachel M. , Li Jinhui , Simons Christopher T. , Bruno Richard S. , Belury Martha A. , Vodovotz Yael
Published: March 2017

As the incidence of obesity continues to increase, identifying novel nutritional therapies to enhance weight loss are needed.
Development of novel β-carboline-based hydroxamate derivatives as HDAC inhibitors with DNA damage and apoptosis inducing abilities
Authors: Liu Ji , Wang Tingting , Wang Xinyang , Luo Lin , Guo Jing , Peng Yanfu , Xu Qibing , Miao Jiefei , Zhang Yanan , Ling Yong
Published: March 2017

A series of novel β-carboline-based hydroxamate derivatives (8a–n) as HDAC inhibitors have been designed and synthesized.
(Co-)polymerization of methylacrylate with NBE/1-hexene by (8-arylimino-5,6,7-trihydroquinolyl)(methyl)palladium chlorides: an approaching mechanism and the polymeric microstructures
Authors: Zeng Yanning , Mahmood Qaiser , Liang Tongling , Sun Wen-Hua
Published: March 2017

The title complexes exhibited a good polymerization performance for MA monomer homopolymerization and copolymerization with either norbornene or 1-hexene as a non-polar monomer affording good co-monomer insertion.
Hybrid preparation of terbium(iii)-doped mesoporous silica particles with calcium phosphates
Authors: Kataoka T. , Shiba K. , Wang L. Y. , Yamada S. , Tagaya M.
Published: March 2017

Terbium-doped mesoporous silica/calcium phosphate interfacial hybrid particles were prepared to demonstrate characteristic luminescence behavior.
A multi-element doping design for a high-performance LiMnPO4 cathode via metaheuristic computation
Authors: Jung Young Hwa , Park Woon Bae , Pyo Myoungho , Sohn Kee-Sun , Ahn Docheon
Published: March 2017

Thanks to the employment of a NSGA-II-based computation, which was used to determine the optimum multi-element doping composition at the Mn site of olivine-structured LiMnPO4, we can propose the first examples of high-performance doped-LiMnPO4 cathodes for Li-ion batteries.
Fully convolutional neural network for removing background in noisy images of uranium bearing particles
Authors: Tarolli Jay G. , Naes Benjamin E. , Butler Lamar , Foster Keeyahna , Gumbs Caleb M. , Howard Andrea L. , Willingham David
Published: March 2017

Removal of background signal with near 99% accuracy from particle SIMS images using a fully convolutional neural network.
Oxidative cyclization of 2-allenyl-1,1′-biphenyls with α-carbonyl alkyl bromides: facile access to functionalized phenanthrenes
Authors: Wang Cheng-Yong , Pan Gao-Hui , Chen Fan , Li Jin-Heng
Published: March 2017

A new copper-facilitated oxidative cyclization of 2-allenyl-1,1′-biphenyls with α-carbonyl alkyl bromides for the synthesis of functionalized phenanthrenes.
Spin-state modulation of molecular FeIII complexes via inclusion in halogen-bonded supramolecular networks
Authors: Jeon Ie-Rang , Jeannin Olivier , Clérac Rodolphe , Rouzières Mathieu , Fourmigué Marc
Published: March 2017

The cationic complex [Fe(qsal)2]+ (Hqsal = N-(8-quinolyl)salicylaldimine) is encapsulated in halogen-bonded 1D and 2D supramolecular networks to modulate its spin-state.
P-Stereogenic bisphosphines with a hydrazine backbone: from N–N atropoisomerism to double nitrogen inversion
Authors: Prades Amparo , Núñez-Pertíñez Samuel , Riera Antoni , Verdaguer Xavier
Published: March 2017

P-Stereogenic C2 diphosphine ligands with a hydrazine backbone are reported. The ligands exist as a mixture of atropo- and nitrogen inversion isomers in slow exchange.
Derivatization and interlaminar debonding of graphite–iron nanoparticle hybrid interfaces using Fenton chemistry
Authors: Agarwal Neha , Bhattacharyya Ruma , Tripathi Narendra K. , Kanojia Sanjay , Roy Debmalya , Mukhopadhyay Kingsuk , Eswara Prasad Namburi
Published: March 2017

Physico-chemical phenomena endure in the nanoscale domains of organic–inorganic interfaces for exfoliation, interfacial debonding and cracking of the graphite sheets.
In situ template synthesis of hollow nanospheres assembled from NiCo2S4@C ultrathin nanosheets with high electrochemical activities for lithium storage and ORR catalysis
Authors: Wu Xiaoyu , Li Songmei , Wang Bo , Liu Jianhua , Yu Mei
Published: March 2017

NiCo2S4@C ultrathin nanosheet assembled hollow nanospheres are fabricated by synchronized sulfurization and in situ template removal, and exhibit high electrochemical activities for lithium storage and ORR catalysis.
Beware of phosphate: evidence of specific dendrimer–phosphate interactions
Authors: Kéri Mónika , Nagy Zoltán , Novák Levente , Szarvas Edit , Balogh Lajos P. , Bányai István
Published: March 2017

G5 PAMAM dendrimers interact with phosphate ions by forming H-bonds with tertiary amino groups in neutral medium.
Ratio-controlled synthesis of phyllosilicate-like materials as precursors for highly efficient catalysis of the formyl group
Authors: Dong Fang , Zhu Yulei , Zhao Haijun , Tang Zhicheng
Published: March 2017

The design and development of heterogeneous catalysts is very critical for the synthesis of various chemicals and fuels derived from superfluous biomass.
Composition-directed FeXMo2−XP bimetallic catalysts for hydrodeoxygenation reactions
Authors: Rensel Dallas J. , Kim Jongsik , Jain Varsha , Bonita Yolanda , Rai Neeraj , Hicks Jason C.
Published: March 2017

Compositional variation in FeXMo2−XP catalysts alters their Lewis acidities, leading to modulated catalytic performance in the hydrodeoxygenation of phenol.
Efficient acceptorless dehydrogenation of secondary alcohols to ketones mediated by a PNN-Ru(ii) catalyst
Authors: Wang Zheng , Pan Bing , Liu Qingbin , Yue Erlin , Solan Gregory A. , Ma Yanping , Sun Wen-Hua
Published: March 2017

The ruthenium(ii) complex, [fac-PNHN]RuCl2(PPh3) (C), in combination with t-BuOK proved an effective and versatile catalyst allowing aromatic-, aliphatic- and cycloalkyl-containing alcohols to be efficiently converted to their corresponding ketones with high values of TON achievable.
Synthesis of microscale and nanoscale ZSM-5 zeolites: effect of particle size and acidity of Zn modified ZSM-5 zeolites on aromatization performance
Authors: Su Xiaofang , Zan Wang , Bai Xuefeng , Wang Gaoliang , Wu Wei
Published: March 2017

Zn/NZ5 zeolite exhibits a higher BTX yield because of the higher mesoporosity and strong Lewis acid sites formed by [ZnOZn]2+species.
Probing the local structure of Prussian blue electrodes by 113Cd NMR spectroscopy
Authors: Flambard A. , Sugahara A. , De S. , Okubo M. , Yamada A. , Lescouëzec R.
Published: March 2017

We demonstrate that 113Cd NMR is a potent technique to monitor the local electronic and structural states of the Prussian blue electrode during Li+ intercalation, providing an atomic-scale insight into the reaction mechanism.
Production and characterization of curcumin microcrystals and evaluation of the antimicrobial and sensory aspects in minimally processed carrots
Authors: Silva Anderson Clayton da , Santos Priscila Dayane de Freitas , Palazzi Nicole Campezato , Leimann Fernanda Vitória , Fuchs Renata Hernandez Barros , Bracht Lívia , Gonçalves Odinei Hess
Published: March 2017

Nontoxic conserving agents are in demand by the food industry due to consumers concern about synthetic conservatives, especially in minimally processed food.
Efficient, selective and sustainable catalysis of carbon dioxide
Authors: Song Qing-Wen , Zhou Zhi-Hua , He Liang-Nian
Published: March 2017

The efficient and selective conversion of CO2as a sustainable C1resource into valuable chemicals and energy-related products through catalysis is reviewed.
Design, synthesis and pharmacological evaluation of new 2-oxo-quinoline derivatives containing α-aminophosphonates as potential antitumor agents
Authors: Yu Yan-Cheng , Kuang Wen-Bin , Huang Ri-Zhen , Fang Yi-Lin , Zhang Ye , Chen Zhen-Feng , Ma Xian-Li
Published: March 2017

Novel 2-oxo-quinoline derivatives containing α-aminophosphonates were synthesized as antitumor agents. Compound 5b blocked HepG2 cell cycle at G2/M phase and induced apoptosis in mitochondrial pathway.
Palladium-catalyzed C–H olefination of uracils and caffeines using molecular oxygen as the sole oxidant
Authors: Zhang Xinyu , Su Lv , Qiu Lin , Fan Zhenwei , Zhang Xiaofeng , Lin Shen , Huang Qiufeng
Published: March 2017

The palladium-catalyzed oxidative C–H olefination of uracils or caffeines with alkenes using an atmospheric pressure of molecular oxygen as the sole oxidant has been disclosed.
Fingerprinting antibiotics with PAE-based fluorescent sensor arrays
Authors: Han Jinsong , Wang Benhua , Bender Markus , Pfisterer Jessica , Huang Wei , Seehafer Kai , Yazdani Mahdieh , Rotello Vincent M. , Rotello Caren M. , Bunz Uwe H. F.
Published: March 2017

We outline an evolution process for 30 tongue elements composed of poly(p-aryleneethynylene)s (PAE) and surfactants, resulting in a powerful pruned tongue for the discrimination of antibiotics.
Superbase catalyzed regio-selective polyhydroalkoxylation of alkynes: a facile route towards functional poly(vinyl ether)s
Authors: Wang Jia , Li Baixue , Xin Dehua , Hu Rongrong , Zhao Zujin , Qin Anjun , Tang Ben Zhong
Published: March 2017

A superbase of t-BuP4 catalysed polyhydroxylation of aromatic diynes was established, and regio-regular poly(vinyl ether)s with versatile properties were produced.
End-chain fluorination of polyesters favors perfluorooctyl bromide encapsulation into echogenic PEGylated nanocapsules
Authors: Houvenagel Sophie , Picheth Guilherme , Dejean Camille , Brûlet Annie , Chennevière Alexis , Couture Olivier , Huang Nicolas , Moine Laurence , Tsapis Nicolas
Published: March 2017

Fluorination of polyesters favors the encapsulation efficiency of perfluorooctyl bromide into nanocapsules.
Facile synthesis of oligo(3-hexylthiophene)s conductive wires with charge-transfer functions
Authors: Öktem Gözde , Sahre Karin , Voit Brigitte , Jordan Rainer , Kiriy Anton
Published: March 2017

A series of fully conjugated oligo(3-hexylthiophene)s bearing different starting- and end-groups have been synthesized by means of externally initiated Kumada catalyst-transfer polymerization (KCTP) and Grignard Metathesis Polymerization (GRIM).
Self-healable hydrogels with cross-linking induced thermo-responsiveness and multi-triggered gel–sol–gel transition
Authors: Wang Xuemeng , Bian Gang , Zhang Miao , Chang Limin , Li Zhiwei , Li Xu , An Heng , Qin Jianglei , Chang Ruixue , Wang Haijun
Published: March 2017

Self-healable hydrogels with cross-linking induced thermo-responsiveness (CIT) were prepared from ketone-group containing P(DMA-stat-DAA).
Electrofluid enhanced hydrolysis of maize starch and its impacts on physical properties
Authors: Zhou Yuyi , Jin Yamei , Yang Na , Xie Zhengjun , Xu Xueming
Published: March 2017

To achieve high-output, successional, and efficient hydrolysis of carbohydrate polymers is an increasing concern in the food and chemical industries.
Stability of carbon and nitrogen isotopic compositions of the protein extracted from milk and their potential as “fingerprints” of geographical origin
Authors: Dong Hao , Xiao Kaijun , Luo Donghui
Published: March 2017

The present work aimed to determine whether isotopic compositions can be used as “fingerprints” in identifying the geographical origin of milk.
Formaldehyde-free melamine microcapsules as core/shell delivery systems for encapsulation of volatile active ingredients
Authors: León G. , Paret N. , Fankhauser P. , Grenno D. , Erni P. , Ouali L. , Berthier D. L.
Published: March 2017

The release of volatile bioactive molecules, such as fragrances, can be controlled by microencapsulation in core–shell polymeric delivery systems.
Controllable synthesis of mesoporous titanosilicates for styrene oxidization using a nanocellulose template strategy
Authors: Shen Dazhi , Liu Jian , Gan Lihui , Huang Naizhong , Long Minnan
Published: March 2017

A nanocellulose-template strategy is reported for the controllable synthesis of mesoporous titanosilicates as efficient catalysts for the oxidization of styrene.
Co9S8@N,P-doped porous carbon electrocatalyst using biomass-derived carbon nanodots as a precursor for overall water splitting in alkaline media
Authors: Liu Rongrong , Zhang Haimin , Zhang Xian , Wu Tianxing , Zhao Huijun , Wang Guozhong
Published: March 2017

Using biomass-derived carbon nanodots as a precursor, Co9S8@N,P-doped porous carbon was fabricated by a molten-salt calcination and post-phosphorization method, and exhibits HER and OER bifunctional catalytic activity.
Significant enhancement of visible light photocatalytic activity of the hybrid B12-PIL/rGO in the presence of Ru(bpy)32+for DDT dehalogenation
Authors: Sun Ying , Zhang Wei , Tong Jian , Zhang Yu , Wu Shuyao , Liu Daliang , Shimakoshi Hisashi , Hisaeda Yoshio , Song Xi-Ming
Published: March 2017

A new hybrid catalyst, B12-PIL/rGO, was prepared. It exhibited enhanced photocatalytic activity for DDT dechlorination in the presence of Ru(bpy)32+.
Metalloradical activation of α-formyldiazoacetates for the catalytic asymmetric radical cyclopropanation of alkenes
Authors: Xu Xue , Wang Yong , Cui Xin , Wojtas Lukasz , Zhang X. Peter
Published: March 2017

For the first time, α-formyldiazoacetates (FDA), have been successfully applied for asymmetric olefin cyclopropanationviaCo(ii)-based metalloradical catalysis.
Cu/Mn bimetallic catalysis enables carbonylative Suzuki–Miyaura coupling with unactivated alkyl electrophiles
Authors: Pye Dominic R. , Cheng Li-Jie , Mankad Neal P.
Published: March 2017

A bimetallic system consisting of Cu-carbene and Mn-carbonyl co-catalysts was employed for carbonylative C–C coupling of arylboronic esters with alkyl halides, allowing for the convergent synthesis of ketones.
Enhanced oxygen evolution on visible light responsive TaON photocatalysts co-loaded with highly active Ru species for IO3− reduction and Co species for water oxidation
Authors: Iwase Yukari , Tomita Osamu , Higashi Masanobu , Abe Ryu
Published: March 2017

Loading an appropriate cocatalyst significantly enhances the activity of semiconductor photocatalysts in both conventional one-step water splitting and Z-scheme-type water splitting with a redox couple.
The role of excess Sn in Cu4Sn7S16 for modification of the band structure and a reduction in lattice thermal conductivity
Authors: He Tongtong , Lin Naiming , Du Zhengliang , Chao Yimin , Cui Jiaolin
Published: March 2017

In this work, we have investigated the band structures of ternary Cu4Sn7+xS16 (x = 0–1.0) compounds with an excess of Sn, and examined their thermoelectric (TE) properties.
Perovskite hybrid solar cells with a fullerene derivative electron extraction layer
Authors: Xu Wenzhan , Yao Xiang , Meng Tianyu , Wang Kai , Huang Fei , Gong Xiong , Cao Yong
Published: March 2017

The performance of perovskite solar cells is enhanced through pyridine-modified PC61BM as an electron extraction layer.
Magnetic poly(2-hydroxyethyl methacrylate) microspheres for affinity purification of monospecific anti-p46 kDa/Myo1C antibodies for early diagnosis of multiple sclerosis patients
Authors: Horák Daniel , Hlídková Helena , Kit Yurii , Antonyuk Volodymyr , Myronovsky Severyn , Stoika Rostyslav
Published: March 2017

The aim of the present study is to develop new magnetic polymer microspheres with functional groups available for easy protein and antibody binding. Monodisperse macroporous poly(2-hydroxyethyl methacrylate) (PHEMA-COOH) microspheres ~4 µm in diameter and containing ∼1 mmol COOH/g were synthesized by multistep swelling polymerization of 2-hydroxyethyl methacrylate (HEMA), ethylene dimethacrylate (EDMA), and 2-[(methoxycarbonyl)methoxy]ethyl methacrylate (MCMEMA), which was followed by MCMEMA hydrolysis. The microspheres were rendered magnetic by precipitation of iron oxide inside the pores, which made them easily separable in a magnetic field. Properties of the resulting magnetic poly(2-hydroxyethyl methacrylate) (mgt.PHEMA) particles with COOH functionality were examined by scanning and transmission electron microscopy (SEM and TEM), static volumetric adsorption of helium and nitrogen, mercury porosimetry, Fourier transform infrared (FTIR) and atomic absorption spectroscopy (AAS), and elemental analysis. Mgt.PHEMA microspheres were coupled with p46/Myo1C protein purified from blood serum of multiple sclerosis (MS) patients, which enabled easy isolation of monospecific anti-p46/Myo1C immunoglobulin G (IgG) antibodies from crude antibody preparations of mouse blood serum. High efficiency of this approach was confirmed by SDS/PAGE, Western blot, and dot blot analyses. The newly developed mgt.PHEMA microspheres conjugated with a potential disease biomarker, p46/Myo1C protein, are thus a promising tool for affinity purification of antibodies, which can improve diagnosis and treatment of MS patients.
Temperament and Early Stuttering Development: Cross-Sectional Findings From a Community Cohort
Authors: Kefalianos Elaina , Onslow Mark , Ukoumunne Obioha C. , Block Susan , Reilly Sheena
Published: March 2017

Purpose

The purpose of this study was to ascertain if there is an association between stuttering severity and behaviors and the expression of temperament characteristics, including precursors of anxiety.

Method

We studied temperament characteristics of a prospectively recruited community cohort of children who stutter (
N
= 173) at ages 3, 4, and 6 years using the Short Temperament Scale STS (Prior, Sanson, Smart & Oberklaid, 2000).

Results

Six of 131 statistical tests of association between stuttering severity and behaviors and temperament traits were statistically significant at the 5% level, which was no more than expected by chance alone.

Conclusions

On the basis of parent responses to the STS, preschoolers who exhibited different levels of stuttering severity and behaviors did not generally express temperament traits differently from one another. Stuttering severity and stuttering behaviors were not associated with the precursors of anxiety. Overall, taking multiple tests into consideration, results show little evidence of association between stuttering severity and temperament up to 4 years of age or between stuttering behaviors and temperament up to 6 years of age.
Analysis of an ideal dual‐impedance network using reference disposition modulation
Authors: Roomi M.M.
Published: March 2017

A single‐impedance network consists of two inductors and capacitors connected in an X‐shape to provide single‐stage energy conversion. This structure eliminates the need for two‐stage energy conversion that is currently employed in traditional converters. A dual‐impedance network includes two individual sets of inductors and capacitors connected in parallel. This network possesses the flexibility of using two different sources as inputs to meet the load demand. In order to provide voltage boosting, the switching must be performed selectively to shoot‐through (ST) the power sources. A modified modulation method has been implemented to introduce the ST for switching. The modified modulation method shares the operating principle with the in‐phase disposition modulation method for multilevel inverters. However, the reference signals are dispositioned via the modified modulation method rather than employing carrier disposition via the traditional modulation methods. Therefore, the circuit analysis of a dual‐impedance network is evaluated whose switching is achieved by a modified modulation method for an ideal condition. The simulations are carried out using the MATLAB/PSIM environment and the results are presented.
Distributed travelling‐wave‐based fault location without time synchronisation and wave velocity error
Authors: Ding Jiali , Li Lixue , Zheng Yihui , Zhao Chunming , Chen Hongtao , Wang Xin
Published: March 2017

Existing single‐ and double‐terminal travelling‐wave fault‐location approaches have some disadvantages including difficulty in distinguishing the sources of reflect and refract waves, system error in time synchronisation and wave propagation velocity. In this study, a distributed travelling‐wave‐based fault‐location system, which eliminates the time synchronisation and wave propagation velocity error, is introduced. This novel system is consisted of three measurement points, which are located at both ends and the mid‐point of the line. At first, the measurement points, installed at both line ends, record the post‐fault current data for a time interval. The measurement point, located at the mid‐point, records the time tags of the three sequential wavefronts as , and separately including the initial wave and following waves reflected at both the ends. Second, by comparing fault current recorded by the three measurement points, the fault interval can be determined based on current deviation theorem. Finally, travelling‐wave propagation velocity is calculated according to mathematic equation in terms of . Then, the fault point is located without the need of time synchronisation. The simulation and hardware tests match the theoretical analysis well, showing that the proposed location method provides not only high accuracy, but also good reliability.
Capacitor impedance estimation utilizing dc‐link voltage oscillations in single phase inverter
Authors: Arya Abhinav , Ahmad Md. Waseem , Agarwal Nikunj , Anand Sandeep
Published: March 2017

Grid tied single‐phase solar inverters offer less operational life when compared with the Photovoltaic (PV) panels due to the use of aluminium electrolytic capacitor (AEC). With time, AEC degrades, resulting in an increase in ripple voltage on PV panel. This would reduce the power extraction efficiency of the system, thereby a loss of revenue. This study proposes a simple and cost‐efficient online technique for monitoring the health of AECs. The proposed technique suggests evaluating the AEC impedance at twice the grid frequency. Sampling of PV voltage, PV current and inductor current is required to determine the second harmonic impedance of AEC. These voltage and current sensors are present in commercially available solar PV inverters for their control operation. The proposed technique could be extended to other single‐phase inverter applications provided that voltage and current sensors are available. Suitable mathematical model of the technique is derived to determine the effect of sampling instant on the accuracy of the results. Criteria for the replacement of capacitor based on impedance monitoring is defined. For validation of the proposed technique, detailed simulation studies are carried out for a single‐phase PV system. The technique is verified experimentally on a scaled down solar PV inverter prototype.
Fourier‐based ISAR imaging using 2D polynomials
Authors: Cantoni Antonio , Martorella Marco
Published: March 2017

Inverse synthetic aperture radar (ISAR) image formation is a problem that has been studied for many decades. Despite the effort made by many researchers and practitioners, it is still an open problem as it involves non‐trivial aspects both in terms of geometry and scattering mechanisms. In this study, the authors introduce a new interpretation of classical ISAR signal modelling, based on two‐dimensional polynomials, providing an alternative perspective that permits the in‐depth investigation of the problem of ISAR image formation when using a Fourier transform‐based approach. The interpretation of target motion compensation and image autofocus are connected through a mathematical formulation that explains in depth what can and should be compensated in the received signal prior to applying the Fourier transform and therefore forming the ISAR image.
Cobalt-Catalyzed Perfluoroalkylation of Quinoline Amides at the C5 Position
Authors: Suo Jian-Feng , Zhao Xue-Mei , Zhang Kai-Xin , Zhou Sheng-Li , Niu Jun-Long , Song Mao-Ping
Published: March 2017

An efficient protocol has been developed for the cobalt-catalyzed perfluoroalkylation of 8-aminoquinoline scaffolds. In the presence of 5 mol% of Co(acac)3 catalyst, the desired products were obtained with exclusive substitution at the C5 position of the quinoline ring after 4 hours. The reaction shows high efficiency and good tolerance for a broad range of functional groups, affording the corresponding products in moderate to good yields.
Complications in Mandibular Midline Distraction
Authors: de Gijt Jan Pieter , Gül Atilla , Wolvius Eppo B. , van der Wal Karel G.H. , Koudstaal Maarten J.
Published: March 2017

Mandibular midline distraction (MMD) is a relatively new surgical technique for correction of transverse discrepancies of the mandible. This study assesses the amount and burden of complications in MMD. A retrospective cohort study was performed on patients who underwent MMD between 2002 and 2014. Patients with congenital deformities or a history of radiation therapy in the area of interest were excluded. Patient records were obtained and individually assessed for any complications. Complications were graded using the Clavien-Dindo classification system (CDS). Seventy-three patients were included of which 33 were males and 40 were females. The mean follow-up was 2.1 years. Twenty-nine patients had minor complications, grades I and II. Two patients had a grade IIIa and three patients had a grade IIIb complication. Common complications were pressure ulcers, dehiscence, and (transient) sensory disturbances of the mental nerve. This study shows that although MMD is a relatively safe method, complications can occur. Mostly the complications are mild, transient, and manageable without the need for any reoperation.
Polygonal pits on silicon surfaces that are created by laser-assisted chemical etching
Authors: Saito Mitsunori , Kimura Saori
Published: March 2017

Laser-assisted chemical etching was conducted for creating periodic textures on silicon surfaces. Silicon plates with the (111) surface orientation were immersed in an aqueous solution of potassium hydroxide, and a pulsed laser beam (532 nm wavelength, 5 ns duration, 10 pulse/s) was irradiated on their surface to promote anisotropic etching. The laser beam was patterned by using a glass capillary plate that contained a hexagonal array of micropores (10μm diameter, 12μm period). The focused beam projected the hexagonal image on the silicon surface, creating bright spots of 4μm period. During the laser irradiation process of 3 min, both laser-induced ablation and chemical etching took place at these bright spots. After stop of laser irradiation, the chemical etching progressed further, and consequently, a periodic array of triangular or hexagonal pits emerged on the silicon surface. The direction of the triangular pits changed by rotation of the silicon plate. When a silicon plate with the (100) surface orientation was used, diamond or rectangular pits were created on its surface. The mechanism of this polygonal texturing was explained by using the normal and intersecting vectors of the (100), (110), and (111) planes that exhibited different etching rates.
Revisiting the hydration structure of aqueous Na+
Authors: Galib M. , Baer M. D. , Skinner L. B. , Mundy C. J. , Huthwelker T. , Schenter G. K. , Benmore C. J. , Govind N. , Fulton J. L.
Published: March 2017

A combination of theory, X-ray diffraction (XRD) and extended x-ray absorption fine structure (EXAFS) are used to probe the hydration structure of aqueous Na+. The high spatial resolution of the XRD measurements corresponds to Qmax = 24 Å−1 while the first-reported Na K-edge EXAFS measurements have a spatial resolution corresponding to 2k = Qmax = 16 Å−1. Both provide an accurate measure of the shape and position of the first peak in the Na–O pair distribution function, gNaO(r). The measured Na–O distances of 2.384 ± 0.003 Å (XRD) and 2.37 ± 0.024 Å (EXAFS) are in excellent agreement. These measurements show a much shorter Na–O distance than generally reported in the experimental literature (Na–Oavg ∼ 2.44 Å) although the current measurements are in agreement with recent neutron diffraction measurements. The measured Na–O coordination number from XRD is 5.5 ± 0.3. The measured structure is compared with both classical and first-principles density functional theory (DFT) simulations. Both of the DFT-based methods, revPBE and BLYP, predict a Na–O distance that is too long by about 0.05 Å with respect to the experimental data (EXAFS and XRD). The inclusion of dispersion interactions (–D3 and –D2) significantly worsens the agreement with experiment by further increasing the Na–O distance by 0.07 Å. In contrast, the use of a classical Na–O Lennard-Jones potential with SPC/E water accurately predicts the Na–O distance as 2.39 Å although the Na–O peak is over-structured with respect to experiment.
Optimizing sparse sampling for 2D electronic spectroscopy
Authors: Roeding Sebastian , Klimovich Nikita , Brixner Tobias
Published: March 2017

We present a new data acquisition concept using optimized non-uniform sampling and compressed sensing reconstruction in order to substantially decrease the acquisition times in action-based multidimensional electronic spectroscopy. For this we acquire a regularly sampled reference data set at a fixed population time and use a genetic algorithm to optimize a reduced non-uniform sampling pattern. We then apply the optimal sampling for data acquisition at all other population times. Furthermore, we show how to transform two-dimensional (2D) spectra into a joint 4D time-frequency von Neumann representation. This leads to increased sparsity compared to the Fourier domain and to improved reconstruction. We demonstrate this approach by recovering transient dynamics in the 2D spectrum of a cresyl violet sample using just 25% of the originally sampled data points.
Local and global dynamics of multi-resolved polymer chains: Effects of the interactions atoms-beads on the dynamic of the chains
Authors: Di Pasquale N. , Carbone P.
Published: March 2017

We present a thorough analysis of the dynamic behaviour of hybrid atomistic/coarse-grained (CG) models of polymer melts. While structural properties are well preserved in a dual-resolved model, we show how the dynamic of the chains can be influenced by the simultaneous presence of atoms and beads. We show that although the polymer chains are long enough to exhibit reptation, the corresponding CG model is unable to capture the expected subdiffusive regimes and seems to still follow the Rouse dynamics. The introduction of atoms in the chain restores the correct dynamic regime, and the dynamics of hybrid systems becomes comparable to that of the atomistic dynamics as the atoms/beads ratio is increased.
Simultaneous feedback control of plasma rotation and stored energy on NSTX-U using neoclassical toroidal viscosity and neutral beam injection
Authors: Goumiri I. R. , Rowley C. W. , Sabbagh S. A. , Gates D. A. , Boyer M. D. , Gerhardt S. P. , Kolemen E. , Menard J. E.
Published: March 2017

A model-based feedback system is presented enabling the simultaneous control of the stored energy through βn and the toroidal rotation profile of the plasma in National Spherical Torus eXperiment Upgrade device. Actuation is obtained using the momentum from six injected neutral beams and the neoclassical toroidal viscosity generated by applying three-dimensional magnetic fields. Based on a model of the momentum diffusion and torque balance, a feedback controller is designed and tested in closed-loop simulations using TRANSP, a time dependent transport analysis code, in predictive mode. Promising results for the ongoing experimental implementation of controllers are obtained.
Reversed interfacial fractionation of carbonate and bicarbonate evidenced by X-ray photoemission spectroscopy
Authors: Lam Royce K. , Smith Jacob W. , Rizzuto Anthony M. , Karslıoğlu Osman , Bluhm Hendrik , Saykally Richard J.
Published: March 2017

The fractionation of ions at liquid interfaces and its effects on the interfacial structure are of vital importance in many scientific fields. Of particular interest is the aqueous carbonate system, which governs both the terrestrial carbon cycle and physiological respiration systems. We have investigated the relative fractionation of carbonate, bicarbonate, and carbonic acid at the liquid/vapor interface finding that both carbonate (CO32−) and carbonic acid (H2CO3) are present in higher concentrations than bicarbonate (HCO3−) in the interfacial region. While the interfacial enhancement of a neutral acid relative to a charged ion is expected, the enhancement of doubly charged, strongly hydrated carbonate anion over the singly charged, less strongly hydrated bicarbonate ion is surprising. As vibrational sum frequency generation experiments have concluded that both carbonate and bicarbonate anions are largely excluded from the air/water interface, the present results suggest that there exists a significant accumulation of carbonate below the depletion region outside of the area probed by sum frequency generation.
Excitonic absorption spectra in graphene nanoflakes: Tuning of exciton binding energy by dielectric environments
Authors: Wang Hao , Sheng Weidong
Published: March 2017

By solving the Bethe-Salpeter equation within the Hartree-Fock formalism, we study the excitonic absorption spectra of graphene nanoflakes embedded in various dielectric environments. With the excitonic effects fully taken into account, the exciton binding energy as a function of the dielectric constant is found to be well described by a single scaling rule in which the scaling factor is found to vary slowly with the size of the nanoflakes. Furthermore, it is revealed that the exciton binding energy scales almost linearly with the on-site interaction energy and exhibits more sensitive dependence in smaller nanoflakes. Our results are found to agree well with the recent experiment.
Current-induced magnetization switching in a nano-scale CoFeB-MgO magnetic tunnel junction under in-plane magnetic field
Authors: Ohshima N. , Sato H. , Kanai S. , Llandro J. , Fukami S. , Matsukura F. , Ohno H.
Published: March 2017

We study current-induced magnetization switching properties of a magnetic tunnel junction with junction diameter of 19 nm and resistance-area product of 6 Ωμm2 in the nanosecond regime with and without in-plane magnetic field. At zero field, for both parallel (P)-to-anti-parallel (AP) and AP-to-P switchings, the probability of switching PSW approaches unity with the increase of pulse voltage duration τP. However, under in-plane magnetic field, PSW for P-to-AP switching starts to saturate at a value lower than unity with increasing τP, while AP-to-P switching remains the same as in the absence of in-plane magnetic field. This in-plane field dependence of PSW can be partially explained by the influence of electric-field modulation of magnetic anisotropy.
Using Mason number to predict MR damper performance from limited test data
Authors: Becnel Andrew C. , Wereley Norman M.
Published: March 2017

The Mason number can be used to produce a single master curve which relates MR fluid stress versus strain rate behavior across a wide range of shear rates, temperatures, and applied magnetic fields. As applications of MR fluid energy absorbers expand to a variety of industries and operating environments, Mason number analysis offers a path to designing devices with desired performance from a minimal set of preliminary test data. Temperature strongly affects the off-state viscosity of the fluid, as the passive viscous force drops considerably at higher temperatures. Yield stress is not similarly affected, and stays relatively constant with changing temperature. In this study, a small model-scale MR fluid rotary energy absorber is used to measure the temperature correction factor of a commercially-available MR fluid from LORD Corporation. This temperature correction factor is identified from shear stress vs. shear rate data collected at four different temperatures. Measurements of the MR fluid yield stress are also obtained and related to a standard empirical formula. From these two MR fluid properties – temperature-dependent viscosity and yield stress – the temperature-corrected Mason number is shown to predict the force vs. velocity performance of a full-scale rotary MR fluid energy absorber. This analysis technique expands the design space of MR devices to high shear rates and allows for comprehensive predictions of overall performance across a wide range of operating conditions from knowledge only of the yield stress vs. applied magnetic field and a temperature-dependent viscosity correction factor.
Magnetic properties and structure of low temperature phase MnBi with island structure
Authors: Ito Masashi , Tanaka Yoshitomo , Satoh Takuya , Mankey Gary , Schad Rainer , Suzuki Takao
Published: March 2017

The magnetic properties of the low temperature phase (LTP) MnBi thin films of islands structure are discussed. The LTP MnBi islands are formed onto silica substrates after the multilayers Bi(3.2nm)/Mn(2nm)x N are deposited and then annealed at 450C for 0.5hr, where N is the number of the repetition of a pair of Mn and Bi layer. Those islands are found to be of the LTP MnBi, with the c-axis orientation along the normal to the sample plane for N=10 ∼ 40. Their size vary from place to place, but are averagely of about a few hundred nm in height and a few μm in width for N from 10 to 40. For N=200, the elongated islands are formed densely, with the length of about a few tens of μm. The coverage of those islands increases with N. The temperature dependence of saturation magnetization Ms is qualitatively similar to that for bulk, though the absolute values for Ms are smaller by 20%. The magnetic anisotropy constants of Ku1 and Ku2 are evaluated for the samples with N=10 ∼ 40, where Ku1 and Ku2 are the magnetic anisotropy constants corresponding to the second and fourth power term in the uniaxial magnetic anisotropy energy expression. It is found that the Ku1 increases with T monotonously, reaching to about 1x107 erg/cc at 400K. On the other hand, the Ku2 remains nearly zero for temperatures below 300K, and then becomes negative, reaching to about 7 x 106 erg/cc at 400K. This is the first to report of the temperature dependence of Ku1 and Ku2 in the LTP MnBi of an island structure. It is also noted that the decrease of Ku for a temperature range beyond around 450 K is possibly due to the decrease of the Ku2 component, as demonstrated in the present study.
Note: A single specimen channel crack growth technique applied to brittle thin films on polymer substrates
Authors: Kim K. , Graham S. , Pierron O. N.
Published: March 2017

We introduce an external-load-assisted thin film channel crack growth technique to measure the subcritical crack growth properties of thin films (i.e., crack velocity, v, versus the strain energy release rate, G), and demonstrate it using 250-nm-thick SiNx films on poly(ethylene terephthalate) substrates. The main particularity of this technique is that it requires a polymer substrate to allow loading to large strains (in order to induce channel cracking) without substrate fracture. Its main advantages are to provide a full v-G curve with a single specimen while relying on a simple specimen preparation and straightforward crack growth characterization. Importantly, the technique can be employed for a much larger range of thin films compared to the residual-stress-driven, thin film channel crack growth tests, including ultrathin films and thin film with residual compressive stresses. The restrictions to a proper use of this technique, related to the (visco)plastic deformation of the substrate, are discussed.
The fate of pancake vortices
Authors: Sutyrin G. G. , Radko T.
Published: March 2017

Nonlinear evolution of pancake-like vortices in a uniformly rotating and stratified fluid is studied using a 3D Boussinesq numerical model at large Rossby numbers. After the initial stage of viscous decay, the simulations reveal exponential growth of toroidal circulation cells (aka Taylor vortices) at the peripheral annulus with a negative Rayleigh discriminant. At the nonlinear stage, these thin cells redistribute the angular momentum and density differently at the levels of radial outflow and inflow. Resulting layering, with a vertical stacking of sharp variations in velocity and density, enhances small-scale mixing and energy decay. Characteristic detectable stretching patterns are produced in the density field. The circulation patterns, induced by centrifugal instability, tend to homogenize the angular momentum in the vicinity of the unstable region. We demonstrate that the peak intensity of the cells and the vortex energy decay are dramatically reduced by the earth’s rotation due to conservation of total absolute angular momentum. The results have important implications for better understanding the fate of pancake vortices and physical mechanisms of energy transfer in stratified fluids.