bluuebunny/crossref_metadata_2025 huggingface dataset:
Quantifying response to intracranial pressure normalization in idiopathic intracranial hypertension via dynamic neuroimaging
Authors: Lublinsky Svetlana , Kesler Anat , Friedman Alon , Horev Anat , Shelef Ilan
Published: September 2017

Background

Idiopathic intracranial hypertension (IIH) is characterized by elevated intracranial pressure without a clear cause.

Purpose

To investigate dynamic imaging findings in IIH and their relation to mechanisms underlying intracranial pressure normalization.

Study Type

Prospective.

Population

Eighteen IIH patients and 30 healthy controls.

Field Strength/Sequence

T1‐weighted, venography, fluid attenuation inversion recovery, and apparent diffusion coefficients were acquired on 1.5T scanner.

Assessment

The dural sinus was measured before and after lumbar puncture (LP). The degree of sinus occlusion was evaluated, based on 95% confidence intervals of controls. We studied a number of neuroimaging biomarkers associated with IIH (sinus occlusion; optic nerve; distribution of cerebrospinal fluid into the subarachnoid space, sulci and lateral ventricles (LVs); Meckel's caves; arachnoid granulation; pituitary and choroid plexus), before and after LP, using a set of specially developed quantification techniques.

Statistical Tests

Relationships among various biomarkers were investigated (Pearson correlation coefficient) and linked to long‐term disease outcomes (logistic regression). The t‐test and the Wilcoxon rank test were used to compare between controls and before and after LP data.

Results

As a result of LP, the following were found to be in good accordance with the opening pressure: relative compression of cerebrospinal fluid (R = –0.857, P < 0.001) and brain volumes (R = –0.576, P = 0.012), LV expansion (R = 0.772, P < 0.001) and venous volume (R = 0.696, P = 0.001), enlargement of the pituitary (R = 0.640, P = 0.023), and shrinkage of subarachnoid space (R = –0.887, P < 0.001). The only parameter that had an impact on long‐term prognosis was cross‐sectional size of supplemental drainage veins after LP (sensitivity of 92%, specificity of 20%, and area under the curve of 0.845, P < 0.001).

Data Conclusion

We present an approach for quantitative characterization of the intracranial venous system and its implementation as a diagnostic assistance tool. We conclude that formation of supplementary drainage veins might serve as a long‐lasting compensatory mechanism.

Level of Evidence: 2

Technical Efficacy: Stage 3

J. Magn. Reson. Imaging 2018;47:913–927.
Inhibitory motor dysfunction in parkinson's disease subtypes
Authors: Gong Tao , Xiang Yuanyuan , Saleh Muhammad G. , Gao Fei , Chen Weibo , Edden Richard A.E. , Wang Guangbin
Published: September 2017

Background

Parkinson's disease (PD) is divided into postural instability gait difficulty (PIGD) and tremor‐dominant (TD) subtypes. Increasing evidence has suggested that the GABAergic neurotransmitter system is involved in the pathogenesis of PD.

Purpose

To evaluate the differences of GABA levels between PD motor subtypes using MEscher‐GArwood Point Resolved Spectroscopy (MEGA‐PRESS).

Study Type: Cohort.

SUBJECTS: PD patients were classified into PIGD (n = 13) and TD groups (n = 9); 16 age‐ and sex‐matched healthy controls were also recruited. All subjects were right‐handed.

Sequence

All subjects underwent an magnetic resonance spectroscopy scan including MEGA‐PRESS at 3.0T.

ASSESSMENT

The detected GABA signal also contains signal from macromolecules (MM) and homocarnosine, so it is referred to as GABA+. GABA + levels and Creatine (Cr) levels were quantified in the left basal ganglia (BG) using Gannet 2.0 by Tao Gong.

Statistical Tests

Differences in GABA + levels between the three groups were analyzed using analysis of covariance. The relationship between GABA levels and a unified PD rating scale (UPDRS) was also analyzed.

Results

GABA + levels were significantly lower in left BG regions of PD patients compared with healthy controls (P < 0.001). In PD patients, the GABA concentration was lower in the TD group than the PIGD group (P = 0.019). Cr levels in PIGD and TD were lower than controls (P = 0.020; P = 0.002). A significant negative correlation was found in PIGD between GABA levels and UPDRS (r = −0.572, P = 0.041), while no correlation was found in TD (r = −0.339, P = 0.372).

Data Conclusion

Low BG GABA levels in PD patients, and differences between PIGD/TD patients, suggest that GABAergic dysfunction may play an important role in the pathogenesis of Parkinson's disease.

Level of Evidence: 1

Technical Efficacy: Stage 2

J. Magn. Reson. Imaging 2018;47:1610–1615.
A systematic tandem mass spectrometric study of anion attachment for improved detection and acidity evaluation of nitrogen‐rich energetic compounds
Authors: Gaiffe Gabriel , Bridoux Maxime C. , Costanza Christine , Cole Richard B.
Published: September 2017

The development of rapid, efficient, and reliable detection methods for the characterization of energetic compounds is of high importance to security forces concerned with terrorist threats. With a mass spectrometric approach, characteristic ions can be produced by attaching anions to analyte molecules in the negative ion mode of electrospray ionization mass spectrometry (ESI‐MS). Under optimized conditions, formed anionic adducts can be detected with higher sensitivities as compared with the deprotonated molecules. Fundamental aspects pertaining to the formation of anionic adducts of 1,3,5,7‐tetranitro‐1,3,5,7‐tetrazocane (HMX), 1,3,5‐trinitro‐1,3,5‐triazinane (RDX), pentaerythritol tetranitrate (PETN), nitroglycerin (NG), and 1,3,5‐trinitroso‐1,3,5‐triazinane energetic (R‐salt) compounds using various anions have been systematically studied by ESI‐MS and ESI tandem mass spectrometry (collision‐induced dissociation) experiments. Bracketing method results show that the gas‐phase acidities of PETN, RDX, and HMX fall between those of HF and acetic acid. Moreover, PETN and RDX are each less acidic than HMX in the gas phase. Nitroglycerin was found to be the most acidic among the nitrogen‐rich explosives studied. The ensemble of bracketing results allows the construction of the following ranking of gas‐phase acidities: PETN (1530‐1458 kJ/mol) > RDX (approximately 1458 kJ/mol) > HMX (approximately 1433 kJ/mol) > nitroglycerin (1427‐1327.8 kJ/mol).
Personality‐based selection of entrepreneurial borrowers to reduce credit risk: Two studies on prediction models in low‐ and high‐stakes settings in developing countries
Authors: Dlugosch Thorsten Johannes , Klinger Bailey , Frese Michael , Klehe Ute‐Christine
Published: September 2017

Small business growth is critical for economic development and poverty reduction in emerging markets, yet there remains an over $2 trillion gap in financing these entrepreneurs. This study explores the potential of personality assessments to help lenders solve this problem and lend to more entrepreneurs and contributes to psychological selection research by examining the effect of high versus low stakes on response distortions and predictive validity in a new area—entrepreneurship with a new dependent variable—paying back credit. Results of Study 1 show that personality assessments are indeed related to credit risk, but response patterns depend significantly on whether or not the assessment is taken as a mandatory part of the credit application (high stakes) or as an optional research survey after the credit has already been provided (low stakes), and predictive relationships do not generalize between these situations. In Study 2, the distributions of personality dimensions relevant for entrepreneurs applying for a credit—conscientiousness, extraversion, and integrity—are shown to be different for applicants when in high‐ versus low‐stakes settings. These findings convey several implications for the research on and practice of lending to entrepreneurs in emerging markets and offer new directions for future research.
Multi‐decadal evolution characteristics of global surface temperature anomaly data shown by observation and CMIP5 models
Authors: Zhu Xian , Dong Wenjie , Wei Zhigang , Guo Yan , Gao Xiaoqing , Wen Xiaohang , Yang Shili , Zheng Zhiyuan , Yan Dongdong , Zhu Yuyao , Chen Juan
Published: September 2017

Based on methods of statistical analysis, the time series of global surface air temperature (SAT) anomalies from 1860 to 2014 has been defined by three types of phase changes that occur through the division of temperature changes into different stages. The characteristics of the three types of phase changes simulated by Coupled Model Inter‐Comparison Project (CMIP5) models were evaluated. The conclusion is as follows: the SAT from 1860 to 2014 can be divided into six stages according to trend differences, and this subdivision is proved to be statistically significant. Based on trend analysis and the distribution of slopes between any two points (two points' slope) in every stage, the six stages can be summarized as three phase changes of warming, cooling, and hiatus. Between 1860 and 2014, the world experienced three heating phases (1860–1878, 1909–1942, and 1975–2004), one cooling phase (1878–1909), and two hiatus phases (1942–1975 and 2004–2014). Using the definition method, whether the next year belongs to the previous phase can be estimated. Furthermore, the temperature in 2015 was used as an example to validate the feasibility of this method. The simulations of the heating period by CMIP5 models are well; however, the characteristics shown by SAT during the cooling and hiatus period cannot be represented by CMIP5 models. As such, the projections of future heating phases using the CMIP5 models are credible, but for cooling and hiatus events they are unreliable.
Temporal continuity of extreme precipitation events using sub‐daily precipitation: application to floods in the Ebro basin, northeastern Spain
Authors: Merino A. , Fernández‐González S. , García‐Ortega E. , Sánchez J. L. , López L. , Gascón E.
Published: September 2017

Extreme precipitation events have been studied widely in various regions because of their implications for hazard assessment and risk management, particularly those of a hydrologic nature. Extreme precipitation events have been commonly defined using daily precipitation series owing to a lack of long‐term data at higher temporal resolution. However, because of their potentially dramatic consequences, intense sub‐daily precipitation is of great importance for risk assessment. Here, we define a new concept of extreme precipitation event based on temporal continuity of that event through run analysis using hourly precipitation. The aim of this definition is to record intense precipitation events over a very short period as well as very persistent rainfall events that produce heavy accumulated precipitation over several days. Both types of event can present considerable hydrologic hazards and are not considered in the definition of extreme precipitation event that is based on a daily time scale. We applied this method to the 29 greatest flood events in the Ebro River basin during 2000–2014 to determine whether our definition can be used to identify events producing hydrologic risks. In addition, we compared the synoptic patterns and trends of events defined using this method and those based on a daily time scale. The results show that the new definition allowed for identification of the 29 analysed flood events (as opposed to extreme events based on a daily time scale), among which eight events were not identified. Moreover, using the new definition facilitates establishment of synoptic patterns and more detailed study of trends by discriminating events according to their duration. The results reveal how the use of daily precipitation can hide trends of shorter events, because positive trends are more dominant in extreme precipitation events at sub‐daily scale.
Optimizing silver‐capped silicon nanopillars to simultaneously realize macroscopic, practical‐level SERS signal reproducibility and high enhancement at low costs
Authors: Wu Kaiyu , Rindzevicius Tomas , Schmidt Michael S. , Thilsted Anil H. , Boisen Anja
Published: September 2017

The ideal surface‐enhanced Raman spectroscopy (SERS) substrate should fulfil the following: (a) predictable SERS enhancement, (b) macroscale SERS signal uniformity, and (c) suitability for mass production at low costs. Macroscale SERS uniformity and reproducibility at practical levels are big obstacles, which have been preventing most SERS substrates from reliable sensing applications. We have previously shown that SERS‐active nanopillar structures, fabricated by lithography‐free processes, exhibit high average SERS enhancements and are mass producible. Here, we report an optimized process and show that the improved structures exhibit unrivalled macroscale SERS uniformities (RSD: ∼2.5% in millimeter scale, ∼7% in wafer scale) and reproducibility (RSD: ∼1.5% across 3 wafers), while at the same time exhibiting a very large average SERS enhancement factor of >108. The obtained SERS uniformity (~2.5% RSD in millimeter scale) is the best to date measured on large‐area solid SERS substrates. Fast and reproducible SERS analysis of trans‐1,2‐bis (4‐pyridyl) ethylene down to 4 × 10−13 mol is demonstrated using the optimized structures. We emphasize that achieving simultaneously macroscopic, practical‐level SERS signal reproducibility and high enhancement via a lithography‐free process is a notable advance towards industrialization of substrate‐based SERS sensors.
Characterization of a thermostable recombinant l‐rhamnose isomerase from Caldicellulosiruptor obsidiansis OB47 and its application for the production of l‐fructose and l‐rhamnulose
Authors: Chen Ziwei , Xu Wei , Zhang Wenli , Zhang Tao , Jiang Bo , Mu Wanmeng
Published: September 2017

BACKGROUND

l‐Hexoses are rare sugars that are important components and precursors in the synthesis of biological compounds and pharmaceutical drugs. l‐Rhamnose isomerase (L‐RI, EC 5.3.1.14) is an aldose–ketose isomerase that plays a significant role in the production of l‐sugars. In this study, a thermostable, l‐sugar‐producing L‐RI from the hyperthermophile Caldicellulosiruptor obsidiansis OB47 was characterized.

RESULTS

The recombinant L‐RI displayed maximal activity at pH 8.0 and 85 °C and was significantly activated by Co2+. It exhibited a relatively high thermostability, with measured half‐lives of 24.75, 11.55, 4.15 and 3.30 h in the presence of Co2+ at 70, 75, 80 and 85 °C, respectively. Specific activities of 277.6, 57.9, 13.7 and 9.6 U mg−1 were measured when l‐rhamnose, l‐mannose, d‐allose and l‐fructose were used as substrates, respectively. l‐Rhamnulose was produced with conversion ratios of 44.0% and 38.6% from 25 and 50 g L−1 l‐rhamnose, respectively. l‐Fructose was also efficiently produced by the L‐RI, with conversion ratios of 67.0% and 58.4% from 25 and 50 g L−1 l‐mannose, respectively.

CONCLUSION

The recombinant L‐RI could effectively catalyze the formation of l‐rhamnulose and l‐fructose, suggesting that it was a promising candidate for industrial production of l‐rhamnulose and l‐fructose. © 2017 Society of Chemical Industry
Dispersive liquid–liquid microextraction based on the solidification of deep eutectic solvent for the determination of benzoylureas in environmental water samples
Authors: Zeng Haozhe , Qiao Kexin , Li Xin , Yang Miyi , Zhang Sanbing , Lu Runhua , Li Jing , Gao Haixiang , Zhou Wenfeng
Published: September 2017

We present a novel dispersive liquid–liquid microextraction method based on the solidification of deep eutectic solvent coupled with high‐performance liquid chromatography with a variable‐wavelength detection for the detection of five benzoylureas in real water samples. In this work, a green solvent consisting of 1‐octyl‐3‐methylimidazolium chloride and 1‐dodecanol was used as an extraction solvent, yielding the advantages of material stability, low density, and a suitable freezing point near room temperature. Parameters that significantly affect extraction efficiency were optimized by the one‐factor‐at‐a‐time approach. Under optimal conditions, the recoveries of five target compounds were obtained ranging from 87.39 to 98.05% with correlation coefficients ranging from 0.9994 to 0.9997 for pure water. The limits of detection were in the range of 0.09–0.16 μg/L. The enrichment factors were in the range of 171–188. Linearities were achieved in the range of 0.5–500 μg/L. The proposed method was successfully applied to determine benzoylureas in environmental water samples with a satisfactory recovery of approximately 81.38–97.67%.
Quantifying small‐magnitude soil erosion: Geomorphic change detection at plot scale
Authors: Balaguer‐Puig Matilde , Marqués‐Mateu Ángel , Lerma José Luis , Ibáñez‐Asensio Sara
Published: September 2017

Soil erosion is a big concern in bare soils from burnt areas and agricultural lands that lack a vegetation cover. In those unprotected soils, intense rain episodes, typical in Mediterranean climate, cause severe soil erosion processes that have been well studied previously using a number of procedures, such as the geomorphic change detection (GCD) method. This method uses digital elevation models (DEMs) of the soil surface and determines the morphological changes in terms of both erosion and deposition by DEMs of difference (DoDs). However, some types of soil erosion, such as diffuse and sheet erosion, may have a small magnitude, at a millimetre scale, and their determination requires methods adapted to that scale. In this paper, we analyse the suitability of the GCD method to account for small magnitude soil erosion. We present a laboratory procedure and setup to represent and quantify sediment budget in small experimental soil plots through differences of DEMs obtained from images using photogrammetric structure from motion. This study explores several key aspects of the technique: establishment of a common reference system for DEMs; determination of errors in the generation of DEMs; selection of appropriate criteria to obtain reliable changes in DoDs; error propagation using Monte Carlo simulation; and validation of the procedure by comparing the results with actual sediments collected during the experiment. Results showed an overestimation of 13% in accumulated soil loss and confirmed that GCD approach with structure from motion‐based DoDs is a suitable method to quantify small‐magnitude erosion events.
Complex Brush‐Like Macromolecular Architectures via Anionic and Ring Opening Metathesis Polymerization: Synthesis, Characterization, and Thermal Properties
Authors: Theodosopoulos George V. , Bitsi Spyridoula‐Lida , Pitsikalis Marinos
Published: September 2017

Combination of anionic and ring opening metathesis (ROMP) polymerizations is conducted for the synthesis of different series of brush polymers adopting the macromonomer methodology. Specifically, poly(tert‐butoxystyrene) (PtBOS), polystyrene (PS), and poly(ethylene oxide) (PEO) macromonomers, having end norbornene groups, are prepared by anionic polymerization techniques and suitable termination reactions or functional anionic initiators. These macromonomers are either homopolymerized or copolymerized by ROMP employing Ruthenium Grubbs catalysts of the 1st or 3rd generation leading to the formation of polymer brushes. Using this synthetic approach, PtBOS polymacromonomers, PtBOS‐PEO block and random copolymacromonomers, and PtBOS‐PS random copolymacromonomers are prepared. Acidic hydrolysis of the tert‐butoxy groups of the PtBOS brushes affords the corresponding polyhydroxystyrene (PSOH) brushes. Subsequent activation of the hydroxyl groups upon reaction with triphenylmethyl potassium and addition of ethylene oxide lead to the formation of PEO brushes on the PSOH brushes (brush on brush structures). These materials are thoroughly characterized by size exclusion chromatography, and 1H‐NMR spectroscopy. The thermal properties are studied by differential scanning calorimetry, thermogravimetric analysis , and differential thermogravimetry.
Cyclic Poly(l‐lactide) via Ring‐Expansion Polymerization by Means of Dibutyltin 4‐Tert‐Butylcatecholate
Authors: Kricheldorf Hans R. , Weidner Steffen M. , Scheliga Felix
Published: September 2017

Five new catalysts are prepared from dibutyltin oxide and catechol (HCa), 2,3‐dihydroxynaphthalene (NaCa), 4‐tert‐butyl catechol (BuCa), 4‐cyano catechol (CyCa), and 4‐benzoyl catechol (BzCa), but only BuCa gives useful results. When benzyl alcohol is used as an initiator, linear chains having benzyl ester end groups are formed in a slow polymerization process. In contrast to cyclic or noncyclic dibutyltin bisalkoxides, neat BuCa yields cyclic poly(l‐lactide)s via a fast ring‐expansion polymerization. Under certain conditions, a high‐melting crystalline phase (T
m = 191 °C) is obtained. At 160 °C and short reaction times even‐numbered cycles are slightly prevailing, but, surprisingly, at 120 °C, odd‐numbered cycles are predominantly formed. These results definitely prove that a ring‐expansion mechanism is operating.
Stability of Adsorbed Polystyrene Nanolayers on Silicon Substrates
Authors: Jiang Naisheng , Cheung JustinM. , Guo Yichen , Endoh Maya K. , Koga Tadanori , Yuan Guangcui , Satija Sushil K.
Published: September 2017

The solid–polymer melt interface is of great scientific interest due to its vital importance in governing a wide array of physical and mechanical properties of polymer thin films. Recent studies have elucidated the coexistence of two different chain conformations of polymer chains adsorbed on a solid (i.e., loosely adsorbed chains and flattened chains). In this work, film stabilities of the polystyrene (PS) “interfacial sublayer” (composed of outer loosely adsorbed chains and inner flattened chains) and flattened layer (composed of the lone flattened chains) prepared on silicon (Si) substrates are investigated. The atomic force microscopy studies reveal that the as‐rinsed PS flattened layer is subjected to spinodal‐like dewetting during a post‐thermal annealing process even at temperatures below the bulk glass transition temperature. Furthermore, it is found that the surface morphology of the flattened layer can be reversibly changed from a homogeneous pattern under good solvent conditions to spinodal‐like droplets under poor solvent conditions. By contrast, it is found that the PS interfacial sublayer remains stable under both good and poor solvent conditions. These findings illuminate the role which density variations within the adsorbed layers play in the mechanism behind the wetting‐dewetting transition.
Influence of Anion and Crosslink Density on the Ionic Conductivity of 1,2,3‐Triazolium‐Based Poly(ionic liquid) Polyester Networks
Authors: Nguyen Anh , Rhoades Taylor C. , Johnson R. Daniel , Miller Kevin M.
Published: September 2017

Covalently crosslinked, 1,2,3‐triazolium‐containing poly(ionic liquid) networks are prepared using Michael addition polymerization. Crosslink density and counteranion are varied in order to decipher the relationships between poly(ionic liquid) (PIL) structure and their thermal, mechanical, and conductive properties. An increase in acrylate concentration leads to a higher crosslink density, as reflected by an increase in the differential scanning calorimetry Tg, dynamic mechanical analyzer E′, and a decrease in the ionic conductivity. Most notable with variable counteranion PILs is that analysis of the ionic conductivity curves reveals a common “crossover” point at ≈85 °C (same acrylate:acetoacetate ratio). Below this crossover temperature, the ionic conductivity appears to be more dependent upon network/polymer chain dynamics. Above 85 °C, the conductivity correlates best with the size of the counteranion. All of the PILs reported here exhibit good ionic conductivities (10−6 to 10−8 S cm−1@25 °C, 30% RH), supporting the notion that 1,2,3‐triazolium‐containing PILs represent a vastly underrated electroactive material platform.
An eigenvalue approach for the automatic scaling of unknowns in model‐based reconstructions: Application to real‐time phase‐contrast flow MRI
Authors: Tan Zhengguo , Hohage Thorsten , Kalentev Oleksandr , Joseph Arun A. , Wang Xiaoqing , Voit Dirk , Merboldt K. Dietmar , Frahm Jens
Published: September 2017

The purpose of this work is to develop an automatic method for the scaling of unknowns in model‐based nonlinear inverse reconstructions and to evaluate its application to real‐time phase‐contrast (RT‐PC) flow magnetic resonance imaging (MRI). Model‐based MRI reconstructions of parametric maps which describe a physical or physiological function require the solution of a nonlinear inverse problem, because the list of unknowns in the extended MRI signal equation comprises multiple functional parameters and all coil sensitivity profiles. Iterative solutions therefore rely on an appropriate scaling of unknowns to numerically balance partial derivatives and regularization terms. The scaling of unknowns emerges as a self‐adjoint and positive‐definite matrix which is expressible by its maximal eigenvalue and solved by power iterations. The proposed method is applied to RT‐PC flow MRI based on highly undersampled acquisitions. Experimental validations include numerical phantoms providing ground truth and a wide range of human studies in the ascending aorta, carotid arteries, deep veins during muscular exercise and cerebrospinal fluid during deep respiration. For RT‐PC flow MRI, model‐based reconstructions with automatic scaling not only offer velocity maps with high spatiotemporal acuity and much reduced phase noise, but also ensure fast convergence as well as accurate and precise velocities for all conditions tested, i.e. for different velocity ranges, vessel sizes and the simultaneous presence of signals with velocity aliasing. In summary, the proposed automatic scaling of unknowns in model‐based MRI reconstructions yields quantitatively reliable velocities for RT‐PC flow MRI in various experimental scenarios.
New Era in shared cellular networks: Moving into open and virtualized platform
Authors: Narmanlioglu Omer , Zeydan Engin
Published: September 2017

Software‐defined networking (SDN) concept provides many features including hardware abstraction, programmable networking and centralized policy control. This allows benefiting from recently developed open source frameworks to build service platforms from a dynamic softwarized ecosystem of networking. There are two major technologies for building the next generation mobile network: Radio Access Network (RAN) sharing and Cloud RAN (C‐RAN). RAN sharing ensures efficient usage of network equipment among multiple mobile network operators (MNOs) and C‐RAN benefits installation, evolution, management, and performance improvements. One of the main benefits that can be used along with these features is dynamic virtualization of RAN and core/backhaul networks to ensure network sharing among multiple MNOs for efficient usage of their network infrastructures. In this work, we propose an SDN‐based C‐RAN architecture managed by C‐RAN controllers, which are integrated with a virtualization controller that is crucial for core/backhaul network sharing of the proposed next generation cellular network architecture. We further provide a use case study of shared mobile architecture for channel‐aware remote radio head (RRH) assignment to multiple MNOs. Two C‐RAN–aided cooperative algorithms, named ANCESTOR and MORGAN, that ensure load balancing among RRHs and better received signal strength levels are provided. Moreover, by selecting MNO assignments judiciously, MORGAN is shown to converge to a pure strategy Nash Equilibrium with high probability in the shared network architecture. The results reveal the proposed methods' performance advantages over static distribution and convergence properties.
An Investigation on Reliable Analytical and Numerical Methods for the Riesz Fractional Nonlinear Schrödinger Equation inQuantum Mechanics
Authors: Saha Ray Santanu
Published: September 2017

In the article, a nonlinear Schrödinger equation with the Riesz fractional derivative has been considered. This equation has been solved by two reliable methods to investigate the accuracy of the solutions. In the implicit finite difference numerical scheme, the fractional centered difference is utilized to approximate the Riesz fractional derivative. Also, a novel modified optimal homotopy asymptotic method with Fourier transform (MOHAM‐FT) has been proposed to compute the approximate solution of Riesz fractional nonlinear Schrödinger equation(RFNLSE). Further the numerical solutions of RFNLSE obtained by proposed implicit finite difference method, have been compared with that obtained by MOHAM‐FT to exhibit the effectiveness of the suggested methods. Finally, the obtained solutions have been presented graphically to justify the efficiency of the methods.
Graphene‐polymer nanocomposites for biomedical applications
Authors: Silva Magda , Alves Natália M. , Paiva Maria C.
Published: September 2017

Despite the significant efforts in the synthesis of new polymers, the mechanical properties of polymer matrices can be considered modest in most cases, which limits their application in demanding areas. The isolation of graphene and evaluation of its outstanding properties, such as high thermal conductivity, superior mechanical properties, and high electronic transport, have attracted academic and industrial interest, and opened good perspectives for the integration of graphene as a filler in polymer matrices to form advanced multifunctional composites. Graphene‐based nanomaterials have prompted the development of flexible nanocomposites for emerging applications that require superior mechanical, thermal, electrical, optical, and chemical performance. These multifunctional nanocomposites may be tailored to synergistically combine the characteristics of both components if proper structural and interfacial organization is achieved. The investigations carried out in this aim have combined graphene with different polymers, leading to a variety of graphene‐based nanocomposites. The extensive research on graphene and its functionalization, as well as polymer graphene composites, aiming at applications in the biomedical field, are reviewed in this paper. An overview of the polymer matrices adequate for the biomedical area and the production techniques of graphene composites is presented. Finally, the applications of such nanocomposites in the biomedical field, particularly in drug delivery, wound healing, and biosensing, are discussed.
Synthesis and electromagnetic shielding behaviour of poly(o‐toluidine)/red mud composite
Authors: Gairola S.P. , Pande Anu , Gairola Preeti , Sharma Sudesh , Purohit L.P. , Dhawan S.K.
Published: September 2017

This paper is an attempt to find out application of red mud in controlling electromagnetic pollution. Composite of PoT/RM has been prepared by in‐situ chemical oxidative polymerization and has been tested for electromagnetic shielding effectiveness. Red mud here acted as a filler material. The incorporation of 50 wt% red mud in the polymer matrix results in a shielding effectiveness of 8.9 dB in 8.2 to 12.4 GHz frequency range (X‐band). Furthermore, the structural analysis, morphology, and magnetization have been studied using XRD, TEM, and VSM techniques, respectively. TEM image of the composite shows the distribution of red mud particles in the polymer matrix. The magnetization decreases on incorporation of red mud in the polymer matrix.
Constituting of a new surface‐initiating system on polymeric microspheres and preparation of basic protein surface‐imprinted material in aqueous solution
Authors: Gao Baojiao , Chen Tao , Cui Kunli
Published: September 2017

In this work, a new surface‐initiating system was constituted on the surfaces of cross‐linked polyvinyl alcohol (CPVA) microspheres, and on this basis, papain surface‐imprinted material was successfully prepared in aqueous solution. CPVA microspheres were modified with chlorethamin as reagent, and so a mass of primary amino group was introduced onto CPVA microspheres. Whereupon, a surface initiating system (−NH2/S2O82−) was formed at the interface between the microspheres and aqueous solution, in which papain as template protein, 4‐styrene sulfonate (SSS) as functional monomer, N,N′‐methylenebisacrylamide (MBA) as cross‐linker and (NH4)2S2O8 as initiator were all dissolved. In neutral solution, the polypeptide chains of papain as a basic protein were positively charged, and the molecules of anionic monomer SSS would spontaneously gather around papain polypeptide chain, forming complex by right of strong electrostatic interaction. The free radicals produced on CPVA microspheres initiated the monomer SSS around papain polypeptide chain and the cross‐linker MBA to produce graft/cross‐linking polymerization, and at the same time, papain macromolecules were embed in the cross‐linked networks. As a result, the graft/cross‐linking polymerizing of SSS and the molecule imprinting of papain were synchronously carried out, and papain surface‐imprinted material, MIP‐PSSS/CPVA microspheres, was obtained. The experimental results show that the papain surface‐imprinted material has excellent binding affinity and high recognition selectivity for papain. The binding capacity of MIP‐PSSS/CPVA microspheres for papain reaches 44 mg/g, and relative to another basic protein, trypsin (TRY) as contrast protein, the selectivity coefficient of MIP‐PSSS/CPVA microspheres for papain is 14.35, displaying very high recognition specificity.
Vitamin D deficiency and outcomes in pediatric hematopoietic stem cell transplantation
Authors: Beebe Kristen , Magee Kyrie , McNulty Annmarie , Stahlecker Jennifer , Salzberg Dana , Miller Holly , Mirea Lucia , Adams Roberta , Ngwube Alexander
Published: September 2017

Background

Pediatric patients undergoing hematopoietic stem cell transplantation (HSCT) are frequently diagnosed with vitamin D deficiency, which may impact outcomes.

Objectives

: To estimate the prevalence of vitamin D deficiency and examine its association with short‐term survival in pediatric HSCT patients.

Methods

Patients undergoing HSCT at Phoenix Children's Hospital were retrospectively identified. Routine serum 25‐hydroxyvitamin D measurements were described prior to transplant and at 100 days and 1‐year post‐HSCT. Associations of pre‐HSCT vitamin D groups (i.e., normal ≥30 ng/ml, insufficient 20–29 ng/ml, and deficient <30 ng/ml) with demographics, clinical factors, and outcomes were examined using nonparametric tests and Cox proportional hazards analyses.

Results

: Among 72 study subjects, the median vitamin D pre‐HSCT was 26 ng/ml (range: 19–34 ng/ml). Levels were insufficient and deficient in 25 (35%) and 20 (28%) patients, respectively, with only two (3%) patients on supplemental therapy pre‐HSCT. Despite supplemental therapy provided to 46 (74%) subjects, insufficient/deficient rates did not significantly change between pre‐HSCT and 100 days post‐HSCT, but mean vitamin D levels significantly increased by 1‐year post‐HSCT (P = 0.01).Vitamin D pre‐HSCT was not associated with the development of acute or chronic graft‐versus‐host disease (GVHD) or delayed engraftment. Overall 1‐year survival was significantly lower for patients with deficient (65%) compared to normal (93%) pre‐HSCT vitamin D (P = 0.001).

Conclusion

Suboptimal vitamin D levels are common in pediatric patients scheduled to receive HSCT and are associated with lower overall 1‐year survival. Further study is warranted to delineate the mechanisms underlying the role of vitamin D in successful HSCT.
Resistance mechanism of Fusarium fujikuroi to phenamacril in the field
Authors: Hou Yi‐Ping , Qu Xiang‐Pu , Mao Xue‐Wei , Kuang Jing , Duan Ya‐Bing , Song Xiu‐shi , Wang Jian‐Xin , Chen Chang‐Jun , Zhou Ming‐Guo
Published: September 2017

BACKGROUND

Rice bakanae disease, mainly caused by Fusarium fujikuroi, is an important disease of rice. Phenamacril has been used to control the disease for a few years in China. In 2016, nine phenamacril‐resistant strains were found in the field in Zhejiang Province. The aim of the study was to clarify the mechanism of resistance of F. fujikuroi to phenamacril and the fitness of resistant strains.

RESULTS

The nine F. fujikuroi strains examined were highly resistant to phenamacril. Eight of them had the point mutation TCA (Ser) → CCA (Pro) at codon 219 in the Myosin‐5 protein, while the other had the point mutation TCA (Ser) → TTA (Leu) at codon 219. Myosin‐5 replacement between resistant and sensitive strains confirmed that the point mutation in Myosin‐5 caused the resistance of F. fujikuroi to phenamacril. Docking of phenamacril into the modeled binding pocket of Myosin‐5 showed that the affinity between phenamacril and Myosin‐5 decreased and a hydrogen bond could not be formed between phenamacril and the amino acid at codon 219 after it changed to Pro or Leu. There was no cross‐resistance between phenamacril and other fungicides. The eight resistant strains containing the point mutation S219P had almost the same fitness as the sensitive strains, while the one resistant strain containing the point mutation S219 L showed decreased mycelial growth, sporulation and pathogenicity.

CONCLUSION

In the field, the point mutation S219P or S219 L in Myosin‐5 conferred high resistance to phenamacril in F. fujikuroi. The point mutation S219P did not affect the fitness of F. fujikuroi, while the point mutation S219 L decreased its fitness. © 2017 Society of Chemical Industry
Coherence Properties and Quantum Control of Silicon Vacancy Color Centers in Diamond
Authors: Becker Jonas Nils , Becher Christoph
Published: September 2017

Atomic‐scale impurity spins, also called color centers, in an otherwise spin‐free diamond host lattice have proven to be versatile tools for applications in solid‐state‐based quantum technologies ranging from quantum information processing (QIP) to quantum‐enhanced sensing and metrology. Due to its wide band gap, diamond can host hundreds of different color centers. However, their suitability for QIP or sensing applications has only been tested for a handful of these, with the nitrogen vacancy (NV) strongly dominating this field of research. Due to its limited optical properties, the success of the NV for QIP applications however strongly depends on the development of efficient photonic interfaces. In the past years the negatively charged silicon vacancy (SiV−) center received significant attention due to its highly favourable spectral properties such as narrow zero phonon line transitions and weak phonon sidebands. Here, the recent work investigating the SiV center's orbital and electron spin coherence properties is reviewed as well as techniques to coherently control its quantum state using microwave as well as optical fields. Also, potential future experimental directions to improve the SiV's coherence time scale and to develop it into a valuable tool for QIP applications are outlined.
Aqueous Extracts of Wild Mushrooms Show Antimicrobial and Antiadhesion Activities against Bacteria and Fungi
Authors: Klančnik Anja , Megušar Polona , Sterniša Meta , Jeršek Barbara , Bucar Franz , Smole Možina Sonja , Kos Janko , Sabotič Jerica
Published: September 2017

Mushrooms represent promising sources of novel bioactive compounds and can be applied as innovative strategies to control microbial contamination and infection via the food chain. We characterized aqueous extracts from 21 wild basidiomycete mushrooms and the cultivated oyster mushroom, Pleurotus ostreatus, as putative sources of antimicrobial and antiadhesive compounds. Broth microdilutions and adhesion to a polystyrene surface were evaluated on Gram‐positive and Gram‐negative bacteria and on fungi. The aqueous extracts tested showed antimicrobial and antiadhesive activities against these microorganisms. Biochemical analyses of the P. ostreatus extract indicated the involvement of several compounds with different molecular masses. Copyright © 2017 John Wiley & Sons, Ltd.
Electron affinity of modified benzene
Authors: Driver Nicholas , Jena Purusottam
Published: September 2017

The electron affinities of organic molecules obeying Hückel's rule of aromaticity are vanishingly small, if not negative. For example, benzene, a classic example of an aromatic molecule, has an electron affinity of −1.15 eV. Using density functional theory, we have systematically calculated the electron affinities and vertical detachment energies of C6H6 by substituting H with halogen (F) and superhalogen (BO2) moieties, as well as replacing one of the C atoms with B. The ground state geometries were obtained by examining about 330 isomers. The electron affinities are found to steadily increase with these substitutions/replacements, even surpassing that of Cl, the element with the highest electron affinity in the periodic table, in the case of C5BH(BO2)5. In some special cases such as C6H5(BO2) the electron affinity and vertical detachment energy differ by as much as 5 eV, indicating substantial changes in the geometry as the electron is removed from the anion. We hope that the ability to change the negative electron affinity of C6H6 to large positive values by substituting H and/or replacing C atom will motivate experimental studies.
Aluminum‐poor hexacarbalane structures: The transition from localized organoaluminum structures to delocalized polyhedra
Authors: Attia Amr A. A. , Lupan Alexandru , King Robert Bruce
Published: September 2017

The series of hexacarbalanes C6Aln–6Men (n = 7–11) represent a progression from localized organoaluminum structures to delocalized polyhedral structures en route to experimentally known 13‐ and 14‐vertex hexacarbalanes such as (AlMe)8(CCH2Ph)5(µ4H), (AlMe)8(CCH2Ph)5(CCPh), [R4N+]2[(AlH)8(CR)6], and (AlNMe3)2(AlR)6(CR)6. In this connection, the lowest energy seven‐vertex C6AlMe7 structure has a tetrahapto benzene ring with the four AlC(cage) bonding interactions required to give the aluminum the favored octet configuration. Related eight‐vertex C6Al2Me8 structures are found with a benzene ring bound to an Al2 unit with a short AlAl distance of ∼2.55 Å suggesting a formal double bond. However, the lowest energy C6Al2Me8 structure has a dialuminacyclobutene unit fused to a tricyclohexane unit through an Al2 edge. Other relatively low‐energy C6AlMe7 and C6Al2Me8 structures consist of a six‐carbon hexatriene chain either forming a seven‐membered C6Al ring in the seven‐vertex structure or acting as a “flyover” between an Al2 unit. The lowest energy nine‐vertex hexacarbalane C6Al3Me9 has two separate C3 units bridged by both an Al2 pair and a single aluminum atom. Higher energy C6Al3Me9 hexacarbalanes contain a pentadienyl chain and an isolated carbon atom with an imbedded bonded Al3 triangle. The low‐energy 10‐vertex C6Al4Me10 structures have a central Al4 butterfly with nonbonding distances between the wingtips ranging from 3.35 to 3.91 Å. The lowest energy 11‐vertex C6Al5Me11 structure has a central Al4 quadrilateral with a diagonal bridged by the fifth aluminum atom. Higher energy C6Al5Me11 structures have an edge rather than a diagonal of the central Al4 quadrilateral bridged by the fifth aluminum atom.
Quantitative analysis of trace levels of surface contamination by X‐ray photoelectron spectroscopy. Part II: Systematic uncertainties and absolute quantification
Authors: Faradzhev Nadir S. , Hill Shannon B. , Powell Cedric J.
Published: September 2017

We discuss analyses of trace levels of surface contamination using X‐ray photoelectron spectroscopy (XPS). The problem of quantifying common sources of statistical and systematic uncertainties for these measurements is formulated in terms of the needs of extreme ultraviolet lithography, but the results and conclusions are applicable to a broad range of XPS applications. We quantify the systematic uncertainties introduced by particular cases of overlapping peaks on different substrate structures by simulating measured spectra with the National Institute of Standards and Technology Database for the Simulation of Electron Spectra for Surface Analysis (SESSA). One example demonstrates that the relative atomic concentrations of trace elements such as S, P, and halogens on a Ru surface could be dramatically overestimated if the fitting of the overlapping Ru 3d and C 1s peaks excludes the contribution from carbon. We also show how spectra generated by SESSA can be compared with measured spectra to determine absolute amounts of surface impurities on layered samples of the type used for extreme ultraviolet lithography. We provide estimates of the total uncertainty for such measurements by considering the systematic limitations of SESSA and the statistical uncertainties of the measurements. The same procedure can be employed for other multilayered materials. Finally, we describe two approaches for converting XPS detection limits for an elemental impurity in an elemental matrix to the corresponding detection limits for the impurity as a thin film on the surface of the matrix material.
Heterogeneity of the Transmembrane Protein Conformation in Purple Membranes Identified by Infrared Nanospectroscopy
Authors: Giliberti Valeria , Badioli Michela , Nucara Alessandro , Calvani Paolo , Ritter Eglof , Puskar Ljiljana , Aziz Emad Flear , Hegemann Peter , Schade Ulrich , Ortolani Michele , Baldassarre Leonetta
Published: September 2017

Cell membranes are intrinsically heterogeneous, as the local protein and lipid distribution is critical to physiological processes. Even in template systems embedding a single protein type, like purple membranes, there can be a different local response to external stimuli or environmental factors, resulting in heterogeneous conformational changes. Despite the dramatic advances of microspectroscopy techniques, the identification of the conformation heterogeneity is still a challenging task. Tip‐enhanced infrared nanospectroscopy is here used to identify conformational changes connected to the hydration state of the transmembrane proteins contained in a 50 nm diameter cell membrane area, without the need for fluorescent labels. In dried purple membrane monolayers, areas with fully hydrated proteins are found among large numbers of molecules with randomly distributed hydration states. Infrared nanospectroscopy results are compared to the spectra obtained with diffraction‐limited infrared techniques based on the use of synchrotron radiation, in which the diffraction limit still prevents the observation of nanoscale heterogeneity.
Scalable processing and autocovariance computation of big functional data
Authors: Brisaboa Nieves R. , Cao Ricardo , Paramá José R. , Silva‐Coira Fernando
Published: September 2017

This paper presents 2 main contributions. The first is a compact representation of huge sets of functional data or trajectories of continuous‐time stochastic processes, which allows keeping the data always compressed even during the processing in main memory. It is oriented to facilitate the efficient computation of the sample autocovariance function without a previous decompression of the data set, by using only partial local decoding. The second contribution is a new memory‐efficient algorithm to compute the sample autocovariance function. The combination of the compact representation and the new memory‐efficient algorithm obtained in our experiments the following benefits. The compressed data occupy in the disk 75% of the space needed by the original data. The computation of the autocovariance function used up to 13 times less main memory, and run 65% faster than the classical method implemented, for example, in the R package.