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1 Zn2+ detection by MRI using Ln3+-based complexes: The central role of coordination chemistry 2018-05-20             

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Publication date: 15 August 2018
Source:Coordination Chemistry Reviews, Volume 369

Author(s): Célia S. Bonnet

This review deals with the rational design of Gd3+-based complexes for Zn2+ detection. It describes the different possible mechanisms underlying Zn2+ detection with such responsive probes. Those probes are composed of three parts: the Gd3+ complex, the Zn2+ binding unit, and a linker. The role and the importance of each part will be described separately through various examples, and it will be shown how it affects the stability, affinity, and efficacy of the probes. Finally, it will be demonstrated how, knowing the mechanism of action of the complex for Zn2+ detection, such probes can be optimized. The aim is to try to establish relationships between the structure and the efficacy of the agents to design rationally more efficient contrast agents in the future.

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2 Simultaneous inhibition of acrylamide and oil uptake in deep fat fried potato strips using gum Arabic-based coating incorporated with antioxidants extracted from spices 2018-05-19             

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Publication date: October 2018
Source:Food Hydrocolloids, Volume 83

Author(s): Rasha Mousa Ahmed Mousa

Modified hydrocolloid gum Arabic (GA) layers on potato strips have been easily prepared by incorporating individual, binary or ternary combinations of antioxidants extracted from widely used spices (black pepper, red chili, turmeric, coriander and cumin) with gum Arabic before deep-frying. The methodological approach for antioxidants incorporation with GA has been firstly investigated to reduce simultaneously acrylamide (AA) and oil uptake in the final deep fat fried potato strips (DFFPS). Results revealed that the antioxidant capacity of markers and their adsorbed amounts are limiting factors for the efficiency of modified GA layer. It is interesting to observe that the use of antioxidants in ternary combinations improved markedly the performance of GA for the inhibition of AA giving values in the range of 112.1 ± 4.5 to 560.4 ± 6.6 μg/kg that are very close or lower than the acceptable EU benchmark level 500 μg/kg AA in DFFPS. The addition of ternary mixtures (1.5%, w/v) of red chili, turmeric and coriander into the GA (1%, w/v) coating solution (1:2, w/v) for 60 min at ambient temperature has been identified as the most promising inhibitor of AA formation (reduction up to 88%) and oil uptake (reduction up to 84.1%). However, non-modified GA layer attenuated only 20% of AA formation (747.2 ± 9.0 μg/kg) and 45.8% of oil uptake compared with the control sample. These results could be attributed to the formation of modified GA hydrocolloid coating on potato strips with the highest antioxidant capacity (485.3 ± 8.2 TE/100 g) and highest recovery by markers capsaicin, curcumin and linalool. Scanning electron microscope (SEM) photographs confirmed the formation of a rigid (thermal gelation and/or crosslinking) network during frying that has to help cement the cell wall of potato tissue. Furthermore, texture, color and sensory analyses indicated that the proposed GA modified coating had maintained the overall acceptability of DFFPS products.

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3 Consistent clustering of entries in large pairwise comparison matrices 2018-05-17             

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Publication date: 1 December 2018
Source:Journal of Computational and Applied Mathematics, Volume 343

Author(s): J. Benítez, S. Carpitella, A. Certa, A.E. Ilaya-Ayza, J. Izquierdo

In multi-attribute decision making the number of decision elements under consideration may be huge, especially for complex, real-world problems. Typically these elements are clustered and then the clusters organized hierarchically to reduce the number of elements to be simultaneously handled. These decomposition methodologies are intended to bring the problem within the cognitive ability of decision makers. However, such methodologies have disadvantages, and it may happen that such a priori clustering is not clear, and/or the problem has previously been addressed without any grouping action. This is the situation for the case study we address, in which a panel of experts gives opinions about the operation of 15 previously established district metered areas in a real water distribution system. Large pairwise comparison matrices may also be found when building comparisons of elements using large bodies of information. In this paper, we address a consistent compression of an AHP comparison matrix that collapses the judgments corresponding to a given number of compared elements. As a result, an a posteriori clustering of various elements becomes possible. In our case study, such a clustering offers several added benefits, including the identification of hidden or unknown criteria to cluster the considered elements of the problem.





4 Current knowledge of ammonite assemblages from the Štramberk Limestone (Tithonian–lower Berriasian) at Kotouč Quarry, Outer Western Carpathians (Czech Republic) 2018-05-16             

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Publication date: October 2018
Source:Cretaceous Research, Volume 90

Author(s): Zdeněk Vašíček, Petr Skupien, John W.M. Jagt

Forty-two species of perisphinctoid ammonites from the Štramberk Limestone at Kotouč Quarry near Štramberk (Moravia, Czech Republic) have been taxonomically assessed since 2013. Some of these species are contained in old collections at various Moravian-Silesian museums, while others are in the collections of two of us (ZV and PS); all are from Kotouč Quarry. In view of the fact that the Štramberk Limestone usually lacks distinct bedding, the stratigraphical position (ammonite zones) of the taxa identified is derived from literature data. Ammonite species identified document the entire Tithonian to the lower Berriasian. One taxon of early Berriasian age is described as new, Neocosmoceras eliasi. The Tithonian ammonite assemblage, with the exception of the uppermost portion of that stage, is close to those on record from the Mediterranean bioprovince in adjacent countries. In the uppermost Tithonian, a cosmopolitan species, Substeueroceras koeneni, appears. In the lower Berriasian, in addition to Mediterranean representatives, taxa that are known from the Crimean Peninsula and, exceptionally, those from the Subboreal Russian Platform Basin, are present.





5 Spatial comparison of CT-based surrogates of lung ventilation with hyperpolarized Helium-3 and Xenon-129 gas MRI in patients undergoing radiation therapy 2018-05-12             

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Publication date: Available online 10 May 2018
Source:International Journal of Radiation Oncology*Biology*Physics

Author(s): B.A. Tahir, P.J.C. Hughes, S.D. Robinson, H. Marshall, N.J. Stewart, G. Norquay, A. Biancardi, H.-F. Chan, G.J. Collier, K.A. Hart, J.A. Swinscoe, M.Q. Hatton, J.M. Wild, R.H. Ireland

Purpose To develop and apply an image acquisition and analysis strategy for spatial comparison of CT-ventilation images with hyperpolarized gas MRI. Methods 11 lung cancer patients underwent 129Xe and 3He ventilation MRI and co-registered 1H anatomical MRI. Expiratory and inspiratory breath-hold CTs were used for deformable image registration and calculation of three CT-ventilation metrics: Hounsfield unit (CTHU), Jacobian (CTJac) and specific gas volume change (CTSGV). Inspiration CT and hyperpolarized gas ventilation MRI were registered via same-breath anatomical 1H-MRI. Voxel-wise Spearman correlation coefficients were calculated between each CT-ventilation image and its corresponding 3He/129Xe-MRI, and for the mean values in regions of interest (ROIs) ranging from fine to coarse in-plane dimensions of 5x5, 10x10, 15x15 and 20x20, located within the lungs as defined by the same-breath 1H-MRI lung mask. Correlation of 3He and 129Xe-MRI was also assessed. Results Spatial correlation of CT-ventilation against 3He/129Xe-MRI increased with ROI size. For example, for CTHU, mean±SD Spearman coefficients were 0.37±0.19/0.33±0.17 at the voxel-level and 0.52±0.20/0.51±0.18 for 20x20 ROIs, respectively. Correlations were stronger for CTHU than for CTJac or CTSGV. Correlation of 3He with 129Xe-MRI was consistently higher than either gas against CT-ventilation maps over all ROIs (p<0.05). No significant differences were observed between CT-ventilation vs 3He-MRI and CT-ventilation vs 129Xe-MRI. Conclusion Comparison of ventilation-related measures from CT and registered hyperpolarized gas MRI is feasible at a voxel level using a dedicated acquisition and analysis protocol. Moderate correlation between CT-ventilation and MRI exists at a regional level. Correlation between MRI and CT is significantly less than between 3He and 129Xe-MRI, suggesting that CT-ventilation surrogate measures may not be measuring lung ventilation alone.

Teaser

This paper describes: an imaging protocol for acquiring pulmonary CT, 1H, 3He and 129Xe-MRI with similar breath-holds and posture to facilitate accurate spatial comparison of CT-ventilation and hyperpolarized gas ventilation maps via deformable image registration, a validation of CT-ventilation, generated from multi-inflation breath-hold CT, against hyperpolarized gas MRI, a comparison of CT-ventilation against two commonly-used hyperpolarized noble gases (3He and 129Xe) for ventilation imaging, a voxel-wise and ROI-based comparison of CT-ventilation and hyperpolarized gas MRI.



6 Obtaining antimicrobial bilayer starch and polyester-blend films with carvacrol 2018-05-12             

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Publication date: October 2018
Source:Food Hydrocolloids, Volume 83

Author(s): Raquel Requena, María Vargas, Amparo Chiralt

Bilayer films using polyester blends (P) and starch (S) were obtained and characterized, incorporating carvacrol as active compound. Carvacrol was incorporated by spraying it between melt blended and compression moulded sheets or through its incorporation into the chloroform P solution used to obtain P cast films. Different PLA-PHBV ratios (75:25 and 65:35) were tested, with and without 15 wt% of PEG1000, whereas the 75:25 ratio with PEG was only used for cast sheets, based on its better overall properties. Mono and bilayers were characterized as to their tensile and water vapour barrier properties and thermal behaviour. Release kinetics of carvacrol in different food simulants and in in vitro antibacterial activity against Listeria innocua and Escherichia coli were also analysed. Incorporating carvacrol by spraying it between the polyester and starch sheets was not effective at retaining the compound in the bilayers. However, the incorporation of carvacrol into cast P films, and the subsequent formation of bilayers with the S sheets, was highly effective at providing practically total carvacrol retention. These active bilayers exhibited highly improved tensile and water vapour barrier capacity with respect to the S monolayer (87% reduction in WVP, 840% increase in elastic modulus) and inhibited the growth of L. innocua and E. coli from both P or S contact sides of bilayers, depending on the internal diffusion of carvacrol through the bilayer and its adequate release of the compound into the culture medium.

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7 Modifying textural and microstructural properties of low fat Cheddar cheese using sodium alginate 2018-05-11             

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Publication date: October 2018
Source:Food Hydrocolloids, Volume 83

Author(s): Bal Kumari Sharma Khanal, Bhesh Bhandari, Sangeeta Prakash, Dasong Liu, Peng Zhou, Nidhi Bansal

Low fat Cheddar cheese (LFC) with up to 91% fat reduction were prepared using four levels of sodium alginate (alginate): 0.12 (LFCA1), 0.17 (LFCA2), 0.18 (LFCA3) and 0.23% (w/w) (LFCA4). Control full fat cheese (CFFC) and control low fat cheese (CLFC) were used for comparison. Physical characteristics, namely texture profile, microstructure, transverse relaxation time (T2) distribution (measured by low-field NMR) and color were analysed periodically during ripening until 180 days. Texture profile analysis illustrated a significant improvement in texture of alginate added LFC (P < 0.05) as compared to CLFC. The textural attributes of LFCA1 ripened for 30 days were comparable to CFFC ripened for 60 days and beyond. A close resemblance in textural attributes between alginate added LFC and CFFC, not previously reported when using other fat replacers, was observed. Scanning electron micrograph (SEM) images revealed that alginate added LFCs had smoother surfaces as compared to CFFC and CLFC, and the dense and compact protein matrix characteristic of CLFC was not observed. Confocal laser scanning microscopy (CLSM) suggested that the fat particle size, area and volume were affected in all LFCs due to their lower fat level and these parameters increased during ripening in CFFC. NMR results revealed increase in higher mobility water fraction in alginate added cheese compared to CFFC and CLFC. Hunter L, a and b values for alginate added LFCs indicated that they were whiter than CLFC and less yellowish than CFFC at the beginning of ripening; the color of some of the alginate added LFCs was comparable to CFFC after 120 days of ripening. Overall, addition of alginate significantly improved the textural, microstructural properties and color of LFCs, affirming its potential as a promising texture modifier.

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8 Simulation of cross-correlated random field samples from sparse measurements using Bayesian compressive sensing 2018-05-07             

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Publication date: November 2018
Source:Mechanical Systems and Signal Processing, Volume 112

Author(s): Tengyuan Zhao, Yu Wang

Cross-correlated random field samples (RFSs) of engineering quantities (e.g., mechanical properties of materials) are often needed for stochastic analysis of structures when cross-correlation between engineering quantities and spatial/temporal auto-correlation of each quantity are considered. Theoretically, cross-correlated RFSs may be simulated using a cross-correlated random field generator with prescribed random field parameters and cross-correlation. In engineering practice, random field parameters and cross-correlation are often unknown, and they need to be estimated from extensive measurements. When the number of measurements is sparse and limited, due to sensor failure, budget limit etc., it is challenging to accurately estimate random field parameters or properly simulate cross-correlated RFSs. This paper aims to address this challenge by developing a cross-correlated random field generator based on Bayesian compressive sampling (BCS) and Karhunen–Loève (KL) expansion. The generator proposed only requires sparse measurements as input, and provides cross-correlated RFSs with a high resolution as output. The cross-correlated RFSs are able to simultaneously characterize the cross-correlation between different quantities and the spatial/temporal auto-correlation for each quantity. The generator proposed is illustrated using numerical examples. The results show that proposed generator performs reasonably well.





9 Rechargeable batteries based on anion intercalation graphite cathodes 2018-05-02             

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Publication date: January 2019
Source:Energy Storage Materials, Volume 16

Author(s): Miao Zhang, Xiaohe Song, Xuewu Ou, Yongbing Tang

Owing to the low cost, abundance and high working voltage, graphite cathodes have attracted tremendous attention in rechargeable batteries, especially in aluminum ion batteries (AIBs) and dual-ion batteries (DIBs). In this review, firstly, a general introduction is given to distinguish the working mechanism of graphite from the conventional metal oxide used as cathode in batteries. Secondly, the characterization methods of anion intercalated compounds, theoretical simulation of anion intercalation behavior into the graphitic cathode and the kinetic study of anion diffusion in graphite are discussed. Then, progresses and challenges of AIBs with different types of graphite cathode materials are presented. Next, typical DIBs systems with graphite cathode, a variety of anodes and electrolytes are introduced in detail. Finally, a conclusion for battery systems with anion intercalation graphite cathodes is draw, and a perspective is outlined to address the existing technical barriers that need to be overcome in future research direction.





10 Optimization of piston type extrusion (PTE) techniques for 3D printed food 2018-05-02             

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Publication date: October 2018
Source:Journal of Food Engineering, Volume 235

Author(s): Namsoo Peter Kim, Jae-Seok Eo, Diana Cho

The piston type extrusion (PTE) method with the employ of the Internet of Things (IoT) technology for ejecting bio-materials and high viscosity material by using an extruder have been successfully optimized in terms of the head traveling speed and the piston pressure with food materials of various viscosities. Along with mathematical approach by using Hagen Poisoulle (HP) equation governing high viscosity flow, the study demonstrated that the material's qv (volumetric flow rate) has constant output at 3.6 × 10−8 m3/s with the material viscosity of 0.001–1000 Pa.S. and the PTE method has shown to be effective when the water content is higher than 33 wt %. When the high viscosity material is stacked more than 20 layers at an optimized height, the three-dimensional shape can be maintained between the head traveling speed of 1.5 × 10−2 and 2.0 × 10−2 m/s.





 
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