bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of frying on the trans‐fatty acid formation in soybean oils
Authors: Hou Jun‐Cai , Jiang Lian‐Zhou , Zhang Chun‐Wei 
Published: December 2011

AbstractTo evaluate the effects of repeated deep‐frying on the trans‐fatty acid (TFA) formation in soybean oils, simultaneous frying experiments were carried out. French fries were prepared using three different types of soybean oil (pressed soybean oil, PSBO; first‐grade solvent extracted soybean oil, FG‐SESBO; and third‐grade solvent extracted soybean oil, TG‐SESBO). French fries were fried intermittently at 180–185°C for a total frying time of 32 h and at an interval time of 30 min. It was found that the initial amount of total TFAs was 0.29 g/100 g, 0.31 g/100 g, and 0.90 g/100 g in PSBO, TG‐SESBO, and FG‐SESBO, respectively. Before the frying started, the C18:1,t‐9, trans‐linoleic acid (TLA), trans‐linolenic acid (TLNA), and total TFA content of the PSBO and TG‐SESBO were significantly lower than in the FG‐SESBO (p<0.05). However, in the frying oil samples, the final concentration of total TFA in the PSBO, TG‐SESBO, and FG‐SESBO were 1.79 ± 0.17 g/100 g, 1.12 ± 0.10 g/100 g, and 1.70 ± 0.07 g/100 g, which was 6.17‐, 3.61‐, and 1.89‐fold higher that in fresh oil, respectively. The highest increasing slopes of C18:1,t‐9, TLA, TLNA, and total TFA were observed in the PSBO.Practical applications: A high intake of TFAs has been shown to lead to an increased risk of coronary heart disease. Plant oils, particularly soybean oil, have been widely used in the food industry in China. Frying is one of the most common methods to cook food. The formation of TFAs during frying has been shown to be closely related to the temperature and duration of the frying process. However, the effects of frying on the formation of TFAs in different soybean oils have not been well studied. In the present study, we demonstrated that increasing the number of frying cycles can cause an intensive increase in the concentration of TFAs in different types of soybean oil, but especially in PSBO.
The effects of acyl moiety and temperature on the polymerization of sterols
Authors: Lehtonen Mari , Lampi Anna‐Maija , Agalga Flora , Struijs Karin , Piironen Vieno 
Published: December 2011

AbstractUnsaturated lipids are prone to oxidize and polymerize when they are exposed to oxygen, heat, and light. Polymerization of the lipids changes the properties of the media, and it is therefore considered a deterioration process. In the present study, the polymerization of steryl esters was investigated. The effects of acyl moiety and temperature were examined by oxidizing neat cholesteryl stearate, oleate, and linoleate and free cholesterol at two temperatures (100 and 140°C). The formed reaction products were characterized by SEC‐RI and silver coordination ion MS (Ag+‐CIS‐MS). Moreover, the secondary oxidation products of sterol were determined by GC‐FID/MS. High‐molecular size compounds could be detected in the steryl esters after the heat treatment, and the presence of oligomers up to pentamers and hexamers could be indicated. In cholesteryl stearate, 79 mg/g of oligomers were measured after 3 days of heating at 100°C, while in cholesteryl oleate and cholesteryl linoleate, the contents were 569 and 809 mg/g, respectively. As the temperature was increased to 140°C, the rate of polymerization increased. After 1 day of heating, 428 mg/g of oligomers were measured in cholesteryl stearate, 552 mg/g in cholesteryl oleate, and 679 mg/g in cholesteryl linoleate. Free cholesterol remained unaltered at 100°C, but at 140°C, 420 mg/g of oligomers were measured after 1 day of heating. In conclusion, polymerization was a considerable reaction as part of the autoxidation of steryl esters. Moreover, the reaction competed with the formation of secondary oxidation products.Practical applications: Several types of food products are fortified with plant sterols because of their ability to lower serum cholesterol levels. Therefore, it is important to study the oxidation behavior of sterols and their conjugates. The subject is relevant since radicals and oxidation products of sterols may form during the manufacture of the preparations, thus leading to higher contents of oxides and possibly oligomers in the final food products. Polymerization of lipids could affect also the cholesterol‐lowering efficiency of plant sterols in fortified food products. The obtained results improve the knowledge on how the primary and secondary oxidation products react into more stable products that may accumulate during prolonged heating.
Water Management in A PEMFC: Water Transport Mechanism and Material Degradation in Gas Diffusion Layers
Authors: Kandlikar S. G. , Garofalo M. L. , Lu Z. 
Published: December 2011

AbstractIt has now been well recognized that both the performance and durability of proton exchange membrane fuel cells (PEMFCs) are closely related to the water accumulation and transport inside its porous components, particularly in the gas diffusion layer (GDL), and microporous layer (MPL). In this paper, the key GDL and MPL properties that affect water transport through them are first discussed and a review of GDL degradation mechanisms is presented. An intermittent water drainage mechanism across the GDL is discussed. The capillary breakthrough pressure (CBP) and the dynamic capillary pressure (DCP), or recurrent breakthrough dynamics, have been identified as key GDL properties that affect its water management performance and function as indicators of the degradation of GDL material. This work uses a novel ex situ experiment to degrade a GDL by exposing it to an accelerated stress test (AST) that subjects the GDL to elevated operation conditions seen at the cathode side of a PEMFC for an extended period of time. In turn, the effect of the AST on the CBP and DCP is investigated. As a result, a loss of hydrophobicity occurred on the MPL surface. This altered the CBP and DCP, thus decreasing water management in the GDL.
Thermal Effect on Water Transport in Proton Exchange Membrane Fuel Cell
Authors: Thomas A. , Maranzana G. , Didierjean S. , Dillet J. , Lottin O. 
Published: December 2011

AbstractAdequate water management is critical in proton exchange membrane fuel cells for improving performance and durability. In this paper, we present results of experiments allowing to quantify the effect of a temperature difference between anode and cathode flow field plates on the transport of water. The results confirm the existence of a temperature‐gradient driven flux between the anode and cathode compartments. They show the strong interplay between water management and heat management and they confirm that water flows mostly in vapor form through the porous media of the MEA. Apart from the current density and the difference between the temperature of the electrodes and of the flow field plates, the water flux in the direction perpendicular to the membrane is also (weakly) dependent on the humidification of the gases. No significant effect has been measured as a function of the GDL thickness as well as of the presence or absence of a MPL. However, using a MPL improves significantly the performance of the fuel cell.
Erk1/2 MAPK and mTOR signaling sequentially regulates progression through distinct stages of oligodendrocyte differentiation
Authors: Guardiola‐Diaz Hebe M. , Ishii Akihiro , Bansal Rashmi 
Published: December 2011

AbstractMyelination is the culmination of a complex process in which oligodendrocyte (OL) progenitors transition through defined stages in a well‐coordinated differentiation program. The signaling mechanisms that regulate this progression are poorly understood. Here we investigate the role of extracellular signal‐regulated‐kinase‐1,‐2 (Erk1/2) and the mammalian target of rapamycin (mTOR), downstream effectors of the Ras/Raf/Mek/Erk and PI3K/Akt/mTOR pathways, at specific stages of OL development in vitro. Using a panel of developmental stage‐specific antigenic markers and pharmacological inhibitors, we provide evidence that Erk1/2 signaling regulates transition of early progenitors to the late progenitor stage and, as a consequence, to the immature OL stage, but not the transition of immature OL to the mature OL stage. In contrast, mTOR signaling is not required for early progenitor transition to late progenitor stage. Surprisingly, it is also not required for the transition of late progenitors to terminally differentiated immature OLs, as has been reported previously, but is required for the next sequential transition of immature OLs to the mature OL stage. Furthermore, mTOR signaling regulates OL cytoskeletal organization and major myelin protein expression. These in vitro findings correlate with our in vivo data showing that inhibition of mTOR by rapamycin injection attenuated the onset of myelination in the early postnatal brain. Thus, these studies demonstrate that Erk1/2 and mTOR signaling sequentially regulates distinct stages of OL progenitor differentiation and suggest that cells in the OL‐lineage require distinct signaling mechanisms to transition through specific stages of their development. © 2011 Wiley Periodicals, Inc.
Glutamate released by Japanese encephalitis virus‐infected microglia involves TNF‐α signaling and contributes to neuronal death
Authors: Chen Chun‐Jung , OU Yen‐Chuan , Chang Cheng‐Yi , Pan Hung‐Chuan , Liao Su‐Lan , Chen Shih‐Yun , Raung Shue‐Ling , Lai Ching‐Yi 
Published: December 2011

AbstractThe substantial activation of microglia in Japanese encephalitis virus (JEV)‐induced Japanese encephalitis found in numerous studies demonstrates that the disease pathogenesis involves bystander damage caused by microglia‐released mediators. Previously, we reported that microglia synthesized and secreted bioactive mediators with neurotoxic potential into the cultured supernatants in response to JEV infection. In this study, we found that the supernatants of JEV‐infected microglia caused MK801‐inhibitable neuronal damage in cultured neurons, indicating a potential excitotoxic mechanism. Infection with JEV was found to elicit the extracellular glutamate accumulation from microglia but not from neuron and astrocyte cultures. The glutaminase inhibitor 6‐diazo‐5‐oxo‐L‐norleucine, cystine/glutamate antiporter inhibitor α‐aminoadipic acid, and the gap junction inhibitor carbenoxolone reduced JEV infection‐induced microglial glutamate release and neurotoxicity. We further demonstrated that tumor necrosis factor‐alpha (TNF‐α) was a key cytokine which stimulated extensive microglial glutamate release by up‐regulating glutaminase expression via signals involving protein kinase C, cAMP responsive element‐binding protein, and CAAT‐enhancer‐binding protein‐beta. Although the elevated expression of excitatory amino acid transporter 1 and 2 was observed in JEV‐infected cells, the glutamate uptake activity was significantly inhibited by TNF‐α. The JEV infection‐induced alterations, such as the extracellular glutamate release and glutamate‐mediated excitoneurotoxicity, also occurred in neuron/glia cultures. Our findings support a potential link between neuroinflammation and the development of excitotoxic neuronal injury in Japanese encephalitis. The link between neuroinflammation and excitotoxic death may involve a mechanism in which TNF‐α released by microglia plays a facilitory role in glutamate excitoneurotoxicity via up‐regulation of glutamate synthesis and down‐regulation of glutamate uptake. © 2011 Wiley Periodicals, Inc.
Impact of multimodal feedback on simulated ergonomic measurements in a virtual environment: A case study with manufacturing workers
Authors: Hu Bo , Zhang Wei , Salvendy Gavriel 
Published: December 2011

AbstractThe purpose of this study was to evaluate the impact of multimodal feedback on ergonomic measurements in a virtual environment (VE) for a typical simulated drilling task. In total, sixty male manufacturing industry workers were divided into five groups. One group performed the working task in a real environment (RE), and ergonomic measurements for this group were used as the baseline for evaluation. The other four groups performed the same task in a virtual environment with different feedback treatments (visual with or without auditory and/or tactile feedback). Five indices – task completion time, maximum force capacity reduction, body part discomfort, rated perceived exertion, and rated task difficulty – were used to evaluate the measurements of each of the four treatments in VE in comparison to the baseline group in RE. The results indicate that the five indices for each of the four treatment groups were significantly higher than those of the RE group. Moreover, the indices of the visual‐only group were significantly higher than those of the other three groups with auditory and/or tactile feedback treatments. The findings of this study can provide a guideline for ergonomic evaluations of work designs in VE and for establishing a virtual reality simulation system. © 2011 Wiley Periodicals, Inc.
Learning From Our Mistakes: What Matters When Incorporating Blogging in the Content Area Literacy Classroom
Authors: Hungerford‐Kresser Holly , Wiggins Joy , Amaro‐Jiménez Carla 
Published: December 2011

AbstractThis manuscript explores the inclusion of blogging as a pedagogical tool with preservice secondary teachers from a variety of content areas. The authors focus on data collected over two and a half years with preservice teachers in the content literacy classroom setting, specifically highlighting the qualitative data collected to determine students’ perceptions of blogging as a pedagogical strategy. Once the study is discussed, and qualitative findings outlined, the authors provide suggestions for other practitioners considering the use of blogging in their classrooms.
Literate Bodies: Multigenerational Participatory Action Research and Embodied Methodologies as Critical Literacy
Authors: Fox Madeline 
Published: December 2011

AbstractThe recent study Polling for Justice (PFJ) used a multigenerational participatory action research approach with embodied methodologies to document youth experiences of education, criminal justice, and public health in New York City. Through an exploration of the PFJ project, this column demonstrates how participatory action research and embodied methodologies can open up new possibilities for developing critical literacies across difference. Youth and adult researchers in PFJ negotiated with each other, with the literature, and with the public to produce new understandings of the language of criminalization and policing through theatre, images, art, and, most fundamentally, through valuing many kinds of expertise. We found that when we included personal experiences as well as survey data, and when we embodied data, through sculptures, images or scenes, we made room for multiple interpretations of language and data to come into our research collective and enrich the overall analysis.
Raman spectroscopy as a detection and analysis tool for in vitro specific targeting of pancreatic cancer cells by EGF‐conjugated, single‐walled carbon nanotubes
Authors: Karmakar Alokita , Iancu Cornel , Bartos Dana Monica , Mahmood Meena W. , Ghosh Anindya , Xu Yang , Dervishi Enkeleda , Collom Samuel L. , Khodakovskaya Mariya , Mustafa Thikra , Watanabe Fumiya , Biris Alexandru R. , Zhang Yongbin , Ali Syed F. , Casciano Dan , Hassen Samar , Nima Zeid , Biris Alexandru S. 
Published: December 2011

ABSTRACTSingle‐walled carbon nanotubes (SWCNTs) were covalently linked to epidermal growth factor (EGF) proteins through an esterification process that was found to be responsible for the docking of SWCNTs on the human pancreatic cancer cells (PANC‐1) surface, thus providing a mechanism for the enhanced delivery and internalization of the nanotubes. Micro Raman spectroscopy and enzyme‐linked immunosorbent assay were used to evaluate the delivery process and kinetics of the SWCNTs. In vitro studies indicated that the delivery kinetics of SWCNT–EGF conjugates, at a concentration of 85 µg ml−1, to the PANC‐1 cell surfaces was significant in the first 30 min of incubation, but reached a plateau with time in accordance with the establishment of equilibrium between the association and the dissociation of EGF with the cell receptors. SWCNT–EGF conjugates could act as strong thermal ablation agents and could induce higher percentages of cellular death compared with the nontargeted SWCNTs alone. Copyright © 2011 John Wiley & Sons, Ltd.
Alder‐ene reaction: Aromaticity and activation‐strain analysis
Authors: Fernández Israel , Bickelhaupt F. Matthias 
Published: December 2011

AbstractWe have computationally explored the trend in reactivity of the Alder‐ene reactions between propene and a series of seven enophiles using density functional theory at M06‐2X/def2‐TZVPP. The reaction barrier decreases along the enophiles in the order H2CCH2> HCCH > H2CNH > H2CCH(COOCH3) > H2CO > H2CPH > H2CS. Thus, barriers drop in particular, if third‐period atoms become involved in the double bond of the enophile. Activation‐strain analyses show that this trend in reactivity correlates with the activation strain associated with deforming reactants from their equilibrium structure to the geometry they adopt in the transition state. We discuss the origin of this trend and its relationship with the extent of synchronicity between H transfer from ene to enophile and the formation of the new CC bond. © 2011 Wiley Periodicals, Inc. J Comput Chem, 2011
Differential nanofiller cluster formations in dental adhesive systems
Authors: Osorio Estrella , Toledano Manuel , Yamauti Monica , Osorio Raquel 
Published: December 2011

AbstractNanofillers are added to dental adhesives to improve mechanical properties of the hybrid layer. Ethanol or water added to the demineralized dentin to improve adhesive infiltration may produce filler aggregation. OBJECTIVE: To assess the effect of 5 vol% water or ethanol addition on nanoparticles distribution in dental adhesives. METHODS: Six available commercial adhesives systems were selected: Clearfil SE Bond (CSE), Clearfil Protect Bond (CPB), FL‐Bond (FLB), Clearfil S3 (CS3), Bond Force (BF), One Up Bond F plus (OUB), and an experimental adhesive system without filler (EXP). Polymer films were obtained by adding 0 (control) or 5 vol% water or ethanol into the bonding resins. Preparations were light‐cured (40 s). Three specimens were analyzed for each mixture. Three phases and 3D images were taken from each specimen by means of an atomic force microscope in taping mode (TM/AFM). Cluster sizes and surface nanoroughness were assessed. RESULTS: Control specimens from CSE, FLB, OUB, and BF presented clusters. The addition of solvents lead to particles aggregation in tested bonding resins. Ethanol addition produced more aggregates, particularly in adhesives containing fluoraluminosilicate as fillers. CONCLUSIONS: Nanofillers aggregation occurred in all adhesive systems in presence of additional solvents. In general, aggregate sizes were higher after the addition of ethanol. Formed clusters size values are always above the dimensions of the spaces existing between the demineralized collagen fibers. Microsc. Res. Tech. 75:749–757, 2012. © 2011 Wiley Periodicals, Inc.
Pro‐opiomelanocortin gene delivery suppresses the growth of established Lewis lung carcinoma through a melanocortin‐1 receptor‐independent pathway
Authors: Tsai Han‐En , Liu Li‐Feng , Dusting Gregory J. , Weng Wen‐Tsan , Chen San‐Cher , Kung Mei‐Lan , Tee Richard , Liu Guei‐Sheung , Tai Ming‐Hong 
Published: December 2011

AbstractBackgroundPro‐opiomelanocortin (POMC) is the precursor of several neuropeptides, such as corticotropin, melanocyte‐stimulating hormone and the endogenous opioid (β‐endorphin). Our previous studies have indicated that POMC gene delivery inhibited the progression and metastasis of B16‐F10 melanoma via the α‐ melanocyte‐stimulating hormone/melanortin‐1 receptor (MC‐1R) pathway.MethodsIn the present study, the therapeutic efficacy of POMC gene therapy was evaluated in mice bearing established Lewis lung carcinoma (LLC) models both in vitro and in vivo. We also investigated the MC‐1R‐independent mechanism underlying POMC gene therapy.ResultsWe found that POMC gene delivery significantly inhibited the growth and colony formation in MC‐1R‐deficient LLC cells. In addition, POMC gene transfer effectively suppressed the growth of established LLC in mice. The inhibitory mechanisms underlying POMC gene delivery were attibuted to be inhibition of proliferation and the induction of apoptosis. Moreover, POMC gene delivery attenuated tumor β‐catenin signaling by reducing protein levels of β‐catenin and its downstream proto‐oncogenes, including cyclin D1 and c‐myc. Lastly, POMC gene delivery induced a significant suppression of tumor vasculature.ConclusionsThese results support the existence of an MC‐1R‐independent pathway for POMC gene therapy, which further expands the therapeutic spectrum of POMC therapy for multiple types of cancer. Copyright © 2012 John Wiley & Sons, Ltd.
A unified approach to known and unknown cases of Berge's conjecture
Authors: Berger Eli , Hartman Irith Ben‐Arroyo 
Published: December 2011

AbstractBerge's elegant dipath partition conjecture from 1982 states that in a dipath partition P of the vertex set of a digraph minimizing , there exists a collection Ck of k disjoint independent sets, where each dipath P∈P meets exactly min{|P|, k} of the independent sets in C. This conjecture extends Linial's conjecture, the Greene–Kleitman Theorem and Dilworth's Theorem for all digraphs. The conjecture is known to be true for acyclic digraphs. For general digraphs, it is known for k=1 by the Gallai–Milgram Theorem, for k⩾λ (where λis the number of vertices in the longest dipath in the graph), by the Gallai–Roy Theorem, and when the optimal path partition P contains only dipaths P with |P|⩾k. Recently, it was proved (Eur J Combin (2007)) for k=2.There was no proof that covers all the known cases of Berge's conjecture. In this article, we give an algorithmic proof of a stronger version of the conjecture for acyclic digraphs, using network flows, which covers all the known cases, except the case k=2, and the new, unknown case, of k=λ−1 for all digraphs. So far, there has been no proof that unified all these cases. This proof gives hope for finding a proof for all k.
An investigation on reference crop evapotranspiration trend from 1975 to 2005 in Iran
Authors: Kousari Mohammad Reza , Ahani Hossein 
Published: December 2011

AbstractEvapotranspiration is one of the most important factors in agriculture and the hydrological cycle that can be influenced by global warming and climatic changes. In this study, the trend of reference crop evapotranspiration (ET0) computed by penman Penman‐Monteith equation and surveyed in 42 synoptic weather stations during last 3 decades (1975–2005). Nonparametric statistical test, Kendall's rank correlation (or τ test) was used to determine ET0 trends. Although, downward and upward trends were observed, increasing trends had more frequency. Spatial analysis of results indicated upward trends especially in the boundary parts of the country while, no significant trends were distributed in central parts. In addition, correlation analysis between ET0 trend and other climatic parameters trend (the trend of mean temperature, mean of minimum temperature, and mean of maximum temperature, mean of relative humidity, mean of wind speed and mean of sunshine duration) showed that wind is the most effective parameter on ET0. Iran losses more than 70% of annual precipitation by ET0. It is obvious that in this country where there are many limitations for water resources management, increase in ET0 could lead to more problems. Copyright © 2011 Royal Meteorological Society