bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thermal Oxidation Kinetics of Refined Hazelnut Oil
Authors: Solak Rukiye , Turan Semra , Kurhan Sebnem , Erge Hande S. , Karabulut Ihsan 
Published: May 2018

AbstractIn this study, oxidation kinetics of refined hazelnut oil heated at the temperature range from 80 to 180 °C was evaluated. The changes in peroxide value, p‐anisidine value, polymer triglyceride content, α‐tocopherol content, and color values during oxidation were best fitted to zero‐order kinetic model. The rate constants for the p‐anisidine value, polymer triglyceride content, and degradation of α‐tocopherol of hazelnut oil increased at the temperatures between 80 and 160 °C, while the rate constant for peroxide value decreased at the temperatures between 80 and 140 °C. The activation energies for the formation of peroxides (at 80–140 °C), secondary oxidation products such as alkenals, the polymer triglycerides, and degradation of α‐tocopherol were found as 47.49, 29.95, 52.65, and 14.22 kJ mol−1, respectively. The induction period of hazelnut oil was observed to reduce with increasing oxidation times. The increase in the b* value with the oxidation time and temperature was attributed to the fact that the heating process intensified the yellow color of the oil.
Zum Tragverhalten CFK‐umschnürter Stahlbetonstützen mit Kreisquerschnitt
Authors: Käseberg Stefan , Holschemacher Klaus , Curbach Manfred 
Published: May 2018

AbstractNeben CFK‐(carbonfaserverstärkten Kunststoff)Lamellen, die als zusätzlich aufgeklebte oder eingeschlitzte Zugbewehrung bereits seit den 1990er Jahren erfolgreich zur Ertüchtigung bestehender Stahlbetonbauteile Einsatz finden, werden in der Baupraxis in zunehmendem Maß auch CFK‐Gelege verwendet. Mit derartigen Gelegen kann neben der Biege‐ und Querkrafttragfähigkeit von Stahlbetonplatten und ‐balken auch die Tragfähigkeit von Stahlbetonstützen nachträglich erhöht werden. Die CFK‐Gelege werden dabei mittels Epoxidharzkleber vollflächig über die gesamte Höhe der zu ertüchtigenden Stahlbetonstütze entlang ihres Umfangs angeordnet. Der auf der Oberfläche entstehende CFK‐Werkstoff behindert durch die hohe Steifigkeit der Carbonfasern die Dehnung und Ausbreitung des Betons in Querrichtung, wodurch dieser in einen dreidimensionalen Spannungszustand versetzt wird. Dies resultiert in höheren Druckfestigkeiten des umschnürten Betons und führt zu einer Veränderung des Verformungsverhaltens. Der Beitrag gibt zunächst einen Überblick zum Stand der Technik hinsichtlich Planung und Bemessung von CFK‐Umschnürungen gemäß der DAfStb‐Richtlinie „Verstärken von Betonbauteilen mit geklebter Bewehrung“ [1]. Daran anschließend werden Forschungsergebnisse aus der internationalen Literatur mit den Ergebnissen eines an der HTWK Leipzig durchgeführten Versuchsprogramms verglichen und ein Bemessungsvorschlag für CFK‐umschnürte Stützen mit Kreisquerschnitt vorgestellt.
Stereoconvergent 1,4‐Addition Reaction of 5H‐Oxazol‐4‐ones with E,Z Isomeric Mixture of Alkylidene β‐Ketoesters Catalyzed by Chiral Guanidines
Authors: Misaki Tomonori , Tatsumi Toshifumi , Okamoto Tatsumasa , Hayashi Yusuke , Jin Nari , Sugimura Takashi 
Published: May 2018

AbstractA 1,4‐addition reaction of 5H‐oxazol‐4‐ones to alkylidene β‐ketoesters, which was catalyzed by using chiral guanidines via a dynamic kinetic resolution process that involved geometric isomerization of the alkylidene β‐ketoesters, was developed. This method allowed using E,Z isomeric mixture of various acyclic alkylidene β‐ketoesters to obtain the products stereoselectively. The relation between the geometry and the stereoselectivity of products was investigated, and the derivatization of the products to the corresponding α‐acyl‐γ‐lactone was performed.
Septin 9 isoform 1 (SEPT9_i1) specifically interacts with importin‐α7 to drive hypoxia‐inducible factor (HIF)‐1α nuclear translocation
Authors: Tazat Keren , Schindler Susanne , Depping Reinhard , Mabjeesh Nicola J. 
Published: May 2018

AbstractWe have shown previously that septin 9 isoform 1 (SEPT9_i1) protein associates with hypoxia‐inducible factor (HIF)‐1α to augment HIF‐1 transcriptional activity by driving its importin‐α‐mediated nuclear translocation. Using in vitro and in vivo binding assays we identified that HIF‐1α interacts with importin‐α5 and importin‐α7 in prostate cancer cells but only importin‐α7 interacts with SEPT9_i1. The interaction with importin‐α7 was dependent on the first 25 amino acids of SEPT9_i1 that are unique compared to other members of the mammalian septin family. Depletion of endogenous importin‐α7 reduced HIF‐1α levels in the nucleus. Our results provide evidence that there are importin‐α specificities in the cytosolic/nuclear translocation process of HIF‐1α protein, which may act differently under certain pathophysiological circumstances where SEPT9_i1 is overexpressed.
Quantitative survival impact of composite treatment delays in head and neck cancer
Authors: Ho Allen S. , Kim Sungjin , Tighiouart Mourad , Mita Alain , Scher Kevin S. , Epstein Joel B. , Laury Anna , Prasad Ravi , Ali Nabilah , Patio Chrysanta , Clair Jon Mallen‐St. , Zumsteg Zachary S. 
Published: May 2018

BACKGROUNDMultidisciplinary management of head and neck cancer (HNC) must reconcile increasingly sophisticated subspecialty care with timeliness of care. Prior studies examined the individual effects of delays in diagnosis‐to‐treatment interval, postoperative interval, and radiation interval but did not consider them collectively. The objective of the current study was to investigate the combined impact of these interwoven intervals on patients with HNC.METHODSPatients with HNC who underwent curative‐intent surgery with radiation were identified in the National Cancer Database between 2004 and 2013. Multivariable models were constructed using restricted cubic splines to determine nonlinear relations with overall survival.RESULTSOverall, 15,064 patients were evaluated. After adjustment for covariates, only prolonged postoperative interval (P < .001) and radiation interval (P < .001) independently predicted for worse outcomes, whereas the association of diagnosis‐to‐treatment interval with survival disappeared. By using multivariable restricted cubic spline functions, increasing postoperative interval did not affect mortality until 40 days after surgery, and each day of delay beyond this increased the risk of mortality until 70 days after surgery (hazard ratio, 1.14; 95% confidence interval, 1.01‐1.28;P = .029). For radiation interval, mortality escalated continuously with each additional day of delay, plateauing at 55 days (hazard ratio, 1.25; 95% confidence interval, 1.11‐1.41;P < .001). Delays beyond these change points were not associated with further survival decrements.CONCLUSIONSIncreasing delays in postoperative and radiation intervals are associated independently with an escalating risk of mortality that plateaus beyond certain thresholds. Delays in initiating therapy, conversely, are eclipsed in importance when appraised in conjunction with the entire treatment course. Such findings may redirect focus to streamlining those intervals that are most sensitive to delays when considering survival burden.Cancer2018.©2018 American Cancer Society.
Coupling Glucose Dehydrogenation with CO2 Hydrogenation by Hydrogen Transfer in Aqueous Media at Room Temperature
Authors: Ding Guodong , Su Ji , Zhang Cheng , Tang Kan , Yang Lisha , Lin Hongfei 
Published: May 2018

AbstractConversion of CO2 into value‐added chemicals and fuels provides a direct solution to reduce excessive CO2 in the atmosphere. Herein, a novel catalytic reaction system is presented by coupling the dehydrogenation of glucose with the hydrogenation of a CO2‐derived salt, ammonium carbonate, in an ethanol–water mixture. For the first time, the hydrogenation of CO2 to formate by glucose has been achieved under ambient conditions. Under the optimal reaction conditions, the highest yield of formate reached approximately 46 %. We find that the apparent pH value in the ethanol–water mixture plays a central role in determining the performance of the hydrogen‐transfer reaction. Based on the 13C NMR and ESI–MS results, a possible pathway of the coupled glucose dehydrogenation and CO2 hydrogenation reactions was proposed.
Combined in situ infrared reflection absorption spectroscopy–quartz crystal microbalance investigation of the initial growth stages of plasma‐deposited SiOx on polypropylene
Authors: Dietrich J. , Hoppe C. , de los Arcos T. , Grundmeier G. 
Published: May 2018

The early growth stages of SiOx deposited onto polypropylene by plasma‐enhanced chemical vapour deposition were investigated by means of quartz crystal microbalance monitoring in combination with in vacuo characterization of the layers by infrared reflection absorption spectroscopy (IRRAS). Additional ex situ characterization of the thin film morphology was done by atomic force microscopy. The combined analysis allowed us to identify three growth stages. Below the film thickness of 4 nm, the growth is dominated by substrate etching, and the volatile etched fragments are incorporated into the SiOx film. Between 4 and 10 nm thickness, deposition dominates over etching, but etching is still possible through open channels through a not fully cross‐linked SiOx matrix. For thickness above 10 nm, etching of the substrate is completely suppressed, and the SiOx film presents the characteristics of a fully cross‐linked structure.
Efficient detection in uniform linear and planar arrays MIMO systems under spatial correlated channels
Authors: Negrão João Lucas , Abrão Taufik 
Published: May 2018

SummaryIn this paper, the efficiency of various multiple‐input multiple‐output (MIMO) detectors was analyzed from the perspective of highly correlated channels, where MIMO systems have a lack of performance, besides in some cases, an increasing complexity. Considering this hard but a useful scenario, various MIMO detection schemes were accurately evaluated concerning complexity and bit error rate performance. Specifically, successive interference cancellation, lattice reduction, and the combination of them were associated with conventional linear MIMO detection techniques. To demonstrate effectiveness, a wide range of the number of antennas and modulation formats have been considered aiming to verify the potential of such MIMO detection techniques according to their performance‐complexity trade‐off. We have also studied the correlation effect when both transmit and receiver sides are equipped with uniform linear array and uniform planar array antenna configurations. The performance of different detectors is carefully compared when both antenna array configurations are deployed considering a different number of antennas and modulation order, especially under near‐massive MIMO condition. We have also discussed the relationship between the array factor and the bit error rate performance of both antenna array structures.
When phylogeny and ecology meet: Modeling the occurrence of Trichoptera with environmental and phylogenetic data
Authors: Godoy Bruno Spacek , Camargos Lucas Marques , Lodi Sara 
Published: May 2018

AbstractEcological studies are increasingly considering phylogenetic relationships among species. The phylogeny is used as a proxy or filter to improve statistical tests and retain evolutionary elements, such as niche conservation. We used the phylogenetic topology to improve the model for occurrence of Trichoptera genera in Cerrado (Brazilian Savanna) streams. We tested whether parameters generated by logistic models of occurrence, using phylogenetic signals, are better than models generated without phylogenetic information. We used a model with Bayesian updating to examine the influence of stream waterpHand phylogenetic relationship among genera on the occurrence of Trichoptera genera. Then, we compared this model with the logistic model for each Trichoptera genus. The probability of occurrence of most genera increased with waterpH, and the phylogeny‐based explicit logistic model improved the parameters estimated for observed genera. The inferred relationship between genera occurrence and streampHimproved, indicating that phylogeny adds relevant information when estimating ecological responses of organisms. Water with elevated acidity (lowpHvalues) may be restrictive for the occurrence of Trichoptera larvae, especially if the regional streams exhibit neutral to alkaline water, as is observed in the Cerrado region. Using phylogeny‐based modeling to predict species occurrence is a prominent opportunity to extend our current statistical framework based on environmental conditions, as it enables a more precise estimation of ecological parameters.
Can the narrow red bands of dragonflies be used to perceive wing interference patterns?
Authors: Brydegaard Mikkel , Jansson Samuel , Schulz Marcus , Runemark Anna 
Published: May 2018

AbstractDespite numerous studies of selection on position and number of spectral vision bands, explanations to the function of narrow spectral bands are lacking. We investigate dragonflies (Odonata), which have the narrowest spectral bands reported, in order to investigate what features these narrow spectral bands may be used to perceive. We address whether it is likely that narrow red bands can be used to identify conspecifics by the optical signature from wing interference patterns (WIPs). We investigate the optical signatures of Odonata wings using hyperspectral imaging, laser profiling, ellipsometry, polarimetric modulation spectroscopy, and laser radar experiments. Based on results, we estimate the prospects for Odonata perception of WIPs to identify conspecifics in the spectral, spatial, intensity, polarization, angular, and temporal domains. We find six lines of evidence consistent with an ability to perceive WIPs. First, the wing membrane thickness of the studied Odonata is 2.3 μm, coinciding with the maximal thickness perceivable by the reported bandwidth. Second, flat wings imply that WIPs persist from whole wings, which can be seen at a distance. Third, WIPs constitute a major brightness in the visual environment only second after the solar disk. Fourth, WIPs exhibit high degree of polarization and polarization vision coincides with frontal narrow red bands in Odonata. Fifth, the angular light incidence on the Odonata composite eye provides all prerequisites for direct assessment of the refractive index which is associated with age. Sixth, WIPs from conspecifics in flight make a significant contribution even to the fundamental wingbeat frequency within the flicker fusion bandwidth of Odonata vision. We conclude that it is likely that WIPs can be perceived by the narrow red bands found in some Odonata species and propose future behavioral and electrophysiological tests of this hypothesis.
Macadamia Oil Extraction With Alcoholic Solvents: Yield and Composition of Macadamia Oil and Production of Protein Concentrates From Defatted Meal
Authors: Navarro Sandra L. B. , Rodrigues Christianne E. C. 
Published: May 2018

The aim of this study is to evaluate the performance of ethanol and isopropanol in the extraction of macadamia oil and the production of protein concentrates from the defatted meal. Partially defatted macadamia cake is submitted to batch extractions in one stage of contact at 60, 75, and 90 °C, while the sequential extraction trials considering four stages are performed at 75 °C. Oil extraction yield is influenced by the solvent type, temperature, and pre‐treatment of the material. Absolute isopropanol at 90 °C enables to extract 66% of the oil while in the sequential configuration, oil yield up to 96% is attained after four stages. The retention of the solution adhered to the fiber (liquid holdup, LH) is affected by the type of solvent and characteristics of the raw material, being obtained LH values higher than 2. The oil extraction conditions affect negatively on the nitrogen solubility index of the defatted meal. The solvents in absolute degree impact less on the solubility of the proteins, enabling the production of macadamia protein concentrates (protein content of 70%) with functional properties suitable for using in the food industry.Practical Applications: This study is useful to oilseed processors and researchers because it addresses the issue of using macadamia cake as raw material to oil extraction with alcoholic solvents, ethanol, and isopropanol, which are less flammable and toxic than hexane. In addition, it is evaluated the effect of process variables on the oil yield, liquid holdup, and characteristics of the extraction products (oil and defatted meal). The results of this work could help to develop macadamia oil extraction process safe for the workers of oil industry and consumers and, simultaneously, to enable the use of by‐products (defatted meal) in the protein concentrates production.Macadamia oil extraction, from partially defatted macadamia cake, is carried out using ethanol and isopropanol (absolute and hydrated) as solvents. The products of macadamia oil extraction are characterized, thus the extracted oils show typical fatty acid composition and the defatted meal presented higher protein content than raw material. Therefore, from these defatted meals are produced macadamia protein concentrates, which show good functional properties to be used as food ingredients.
Performance of multihop detect‐and‐forward relaying system over fluctuating two‐ray fading channels
Authors: Dixit Dharmendra , Sahu P. R. 
Published: May 2018

AbstractThe performance of multihop detect‐and‐forward relaying system is analyzed over fluctuating two‐ray fading channels for 28 GHz millimeter wave communications. Exact closed‐form expressions for outage probability and average symbol error rate of various modulation schemes over nonidentically distributed fluctuating two‐ray fading channels have been obtained. The derived expressions are given in terms of the Lauricella hypergeometric functions
and
. Moreover, the derived expressions also accommodate several others reported results in the literature for two‐wave diffuse power, Rician, Rician shadowed, Nakagami‐m, and Hoyt fading channels. Asymptotic outage probability and average symbol error rate expressions are also derived, which provide useful insights on the factors governing the performance of the considered system. The numerical results have been verified with Monte‐Carlo simulation results.
Novel underdetermined blind source separation algorithm based on compressed sensing and K‐SVD
Authors: Ruan Guoqing , Guo Qiang , Gao Jingpeng 
Published: May 2018

AbstractIn this paper, a novel two‐stage underdetermined blind source separation (UBSS) algorithm based on eigenvalue decomposition and compressed sensing (CS) is proposed. UBSS techniques can separate the complex mixed signals into multiple single signal components, which are widely applied in the field of electronic surveillance, spectrum management, radar applications, etc. Our major contributions are summarized as follows: (1) deriving a single source points detection algorithm based on eigenvalue decomposition; (2) proposing a novel hierarchical coupling dictionary training method based on K‐means singular value decomposition; and (3) using the two‐stage method to realize the separation of radar signals under the condition of unknown prior information. In the first stage, we present a single source point detection method involving eigenvalue decomposition to estimate the unknown mixing matrix. In this method, the eigenvector corresponding to the maximum eigenvalue is estimated and clustered as a vector of mixing matrix. The second stage is the recovery of sources from the observed signals utilizing the mixing matrix estimated by the first step. In the second stage, we first build the unified model of UBSS and CS, thus the reconstruction algorithm in the CS field can be applied to UBSS. Then, a hierarchical coupling dictionary training method based on K‐means singular value decomposition is proposed. The dictionary training method obtains the prior training signals by pre‐separation and employs the hierarchical coupling idea to train the dictionary efficiently. Simulations illustrate the validity of the method and show that the proposed method outperforms the traditional methods in source separation, especially in real‐world noncooperative cases without prior knowledge.
Content of phenolic compounds and vitamin C and antioxidant activity in wasted parts of Sudanese citrus fruits
Authors: Sir Elkhatim Khitma A. , Elagib Randa A. A. , Hassan Amro B. 
Published: May 2018

AbstractPhenolic compounds, vitamin C, and the antioxidant activity of wasted parts of citrus (orange, lemon, and grapefruit) fruits were investigated. Ethanolic extracts from whole fruit, peel, and pulp containing seeds of each type of citruses were prepared. Within each type of citrus, results revealed that peels contained a higher amount of phenolic compound, flavonoids, vitamin C, and antioxidant activity than those of their inner wasted parts (pulp and seeds). Peels of grapefruit had the highest total phenolic content followed by lemon and orange, which was found to be 77.3, 49.8, and 35.6 mg of gallic acid equivalent/g of peels, respectively. In contrast, orange peels contain the highest amount of flavonoids (83.3 mg of catechin equivalent/g) and vitamin C (110.4 mg/100 g) compared to the peels of the other citrus fruit used in this study. In general, the high content of antioxidant capacity and activity of citrus waste, particularly the peels, indicated that they may impart health and nutritional benefit when involving in the food industry as a natural antioxidant.
Geological suitability and capacity of CO2 storage in the Jiyang Depression, East China
Authors: Wang Shu , Vincent Ceri J. , Zeng Rongshu , Stephenson Michael H. 
Published: May 2018

AbstractCarbon dioxide capture and storage (CCS) is an effective technology to reduce carbon dioxide (CO2) emissions in China. In this paper, the authors considered storage opportunities offered by oil reservoirs and deep saline aquifers in the Jiyang Depression, in east China. Based on detailed geological analysis and assessment of CO2 storage suitability, the Dongying Sag and Linyi‐Shanghe areas of the Huimin Sag within the Jiyang Depression appear promising for CO2 storage. Following more detailed characterization, the second and third members of the Shahejie Formation located in these two areas appear the most promising for CO2 storage. Within the areas identified as having potential for storage, 55 primary and 62 secondary recommended storage units were defined, with a total theoretical capacity of 5.02 × 108 tonnes (t) CO2. This represents storage of CO2 emissions from large‐scale sources in the Jiyang Depression for more than 30 years at current emission rates. © 2018 Society of Chemical Industry and John Wiley & Sons, Ltd.