bluuebunny/crossref_metadata_2025_split huggingface dataset:
Oxyfuel CFBC: status and anticipated development
Authors: Anthony E.J.(Ben) 
Published: March 2013

AbstractMany technologies are now being explored to permit the combustion of fossil fuels while achieving CO2 capture in a state suitable for compression, transporting, and sequestration. Among the chief contenders are processes in which the fuel is first decarbonized, usually by gasification, followed by the use of a shift reaction to produce pure H2; post‐combustion capture, in which the CO2 is removed from the flue gases either at high temperatures (e.g. carbonate or Ca looping) or at near‐ambient temperatures (e.g. amine scrubbing); chemical looping in which the fuel is converted in the presence of a solid oxide carrier, thus producing a stream of gas consisting primarily of CO2 and H2O; and finally, oxyfuel combustion in which the fuel is burned in a stream of pure, or nearly pure, oxygen. The latter technology is already being investigated for application with pulverized fuel or coal, but more recently, the possibility of using oxyfuel combustion with circulating fluidized beds has been receiving increasing attention. There is already a 30 MWth demonstration unit operating in Spain, with plans to build a 300 MWe plant. This perspective describes the current status of oxyfuel research and development. © 2013 Society of Chemical Industry and John Wiley & Sons, Ltd
Height‐dependent transition from 3‐D to 2‐D turbulence in the hurricane boundary layer
Authors: Byrne David , Zhang Jun A. 
Published: March 2013

AbstractHere we show, from in situ aircraft measurements in the hurricane boundary layer, a height‐dependent transition of the flow from 3‐D to 2‐D turbulence. This marks a fundamental change in the energy dynamics of the hurricane boundary layer due to the fact that in 3‐D, energy flows downscale from larger to smaller scales, whereas in 2‐D, it flows upscale, from smaller to larger scales. These results represent the first measurement of the 2‐D upscale energy flux in the atmosphere and also the first to characterize the transition from 3‐D to 2‐D. It is shown that the large‐scale parent vortex may gain energy directly from small scales in tropical cyclones.
Tropical coral reef habitat in a geoengineered, high‐CO2 world
Authors: Couce E. , Irvine P. J. , Gregoire L. J. , Ridgwell A. , Hendy E. J. 
Published: March 2013

AbstractContinued anthropogenic CO2 emissions are expected to impact tropical coral reefs by further raising sea surface temperatures (SST) and intensifying ocean acidification (OA). Although geoengineering by means of solar radiation management (SRM) may mitigate temperature increases, OA will persist, raising important questions regarding the impact of different stressor combinations. We apply statistical Bioclimatic Envelope Models to project changes in shallow water tropical coral reef habitat as a single niche (without resolving biodiversity or community composition) under various representative concentration pathway and SRM scenarios, until 2070. We predict substantial reductions in habitat suitability centered on the Indo‐Pacific Warm Pool under net anthropogenic radiative forcing of ≥3.0 W/m2. The near‐term dominant risk to coral reefs is increasing SSTs; below 3 W/m2 reasonably favorable conditions are maintained, even when achieved by SRM with persisting OA. “Optimal” mitigation occurs at 1.5 W/m2 because tropical SSTs overcool in a fully geoengineered (i.e., preindustrial global mean temperature) world.
Determination of rock acoustic properties at low frequency: A differential acoustical resonance spectroscopy device and its estimation technique
Authors: Zhao Jianguo , Tang Genyang , Deng Jixin , Tong Xiaolong , Wang Shangxu 
Published: March 2013

AbstractA laboratory device, Differential Acoustic Resonance Spectroscopy (DARS), has been developed to investigate the acoustic properties of rock materials below 1 KHz. The device is based on analyzing shifts of resonance frequency of a cavity perturbed by the presence of a small sample. Numerical and experimental studies have previously shown that this technique can be used to estimate the compressibility of samples. In this study, we adopt a nonlinear least‐squares whole‐curve‐fitting inversion approach, which for the first time allows estimation of both the compressibility and density of rock samples. In comparison to previous estimation techniques, this inversion method provides more reliable estimation of rock acoustic properties. This research proves that the DARS laboratory device, in conjunction with the calibration technique proposed herein, is a useful tool to estimate the properties of small rock samples. In addition, the simultaneous estimation of compressibility and density can potentially provide information on porosity and, by extension, a link between porosity and acoustic modulus at low frequency.
P‐Dodecylbenzenesulfonic Acid: A Highly Efficient Catalyst for One‐Pot Synthesis of α‐Aminophosphonates in Aqueous Media
Authors: Movassagh Barahman , Alapour Saba 
Published: March 2013

ABSTRACTA highly efficient one‐pot three‐component reaction of aldehydes or ketones, amines, and trimethyl or triethyl phosphite catalyzed by p‐dodecylbenzensulfonic acid is developed for the synthesis of α‐aminophosphonates at room temperature in water. © 2013 Wiley Periodicals, Inc. Heteroatom Chem 24:174–178, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/hc.21079
Iridoids from the Roots of Valeriana jatamansi
Authors: Li Yuan‐Dan , Wu Zhao‐Yuan , Li Hong‐Mei , Li Hai‐Zhou , Li Rong‐Tao 
Published: March 2013

AbstractThree new iridoids, jatamanins N–P (1–3), along with the seven known iridiods 4–10, were isolated from the roots of Valeriana jatamansi. Compound 1 is an unusual iridoid bearing two epoxy bridges between C(3) and C(6) and between C(1) and C(10), forming a unique cage‐like rigid skeleton. The structures of the new compounds were assigned on the basis of spectroscopic methods.
Temperature‐Dependent Product Selectivity in the VilsmeierHaack Reaction on Bis(phenylhydrazones) of Bis(aroylmethyl) Sulfides (=1,1′‐[Thiobis(methylene)]bis[arylmethanone] Bis(2‐phenylhydrazones)): Synthesis of 3‐Aroylindoles (=Aryl(1H‐indol‐3‐yl)methanones)
Authors: Paul Nidhin , Muthusubramanian Shanmugam 
Published: March 2013

AbstractThe bis(phenylhydrazone) of substituted diphenacyl sulfides (=1,1′‐[thiobis(methylene)]bis[arylmethanone] bis(2‐phenylhydrazones)) 1 underwent a tandem sequence of reactions upon treatment with Vilsmeier reagent, ultimately yielding 3‐aroylindoles (=aryl(1H‐indol‐3‐yl)methanones) 3 (Scheme 1 and Table 1). The reaction seems to be product selective depending upon the reaction temperature.
A Novel Xanthone from Garcinia oligantha
Authors: Gao Xue‐Mei , Cui Ming‐Zhu , Yu Ting , Hu Qiu‐Fen , Pu Jian‐Xin , Du Xue , Liu Tian‐Cheng , Qian Luo Kathy 
Published: March 2013

AbstractOne novel xanthone, oliganthone A (1), was isolated from the stems of the plant Garcinia oligantha. It features the O‐bearing C(3)‐atom and absence of C(4) compared with the structures of related known xanthones, which have never been reported before. The structure of this compound was elucidated by spectroscopic analysis. Compound 1 showed strong HeLa cell growth‐inhibiting effects with IC50 values below 10 μM.
Two New Pentacyclic Triterpenes from Abelmoschus esculentus
Authors: Zhou Yonghui , Jia Xin , Shi Jinmin , Xu Yinpeng , Jing Linlin , Jia Lu 
Published: March 2013

AbstractTwo new pentacyclic triterpenes, (3β,21β)‐19,21‐epoxylup‐20(29)‐en‐3‐yl acetate (1) and (3β)‐9,18‐dihydroxyolean‐12‐en‐3‐yl acetate (2), were isolated from Abelmoschus esculentus (L.) Moench. Their structures were determined on the basis of detailed analyses of their 1D‐ and 2D‐NMR‐spectroscopic and MS data.
New Selenosemicarbazides Derived from Imidazole‐Based Carbohydrazides
Authors: Pieczonka Adam M. , Ciepielowski Krzysztof , Cebulska Zofia , Mlostoń Grzegorz , Linden Anthony , Heimgartner Heinz 
Published: March 2013

AbstractImidazole‐based carbohydrazides, i.e., 3‐oxidoimidazole‐4‐carbohydrazides 1 and 2‐[(imidazol‐2‐yl)sulfanyl]acetohydrazides 6, react with aryl isoselenocyanates 4 in MeOH at room temperature to give the corresponding selenosemicarbazides 5 and 7, respectively, in good yields. On heating 7b in DMF in the presence of air to 100°, 1,3,4‐oxadiazole 8a was formed via cyclization and formal elimination of H2Se. Product 8a was also obtained after heating of a mixture of 4a and 6b under the same conditions. On the other hand, on heating of a solution of 7c in MeOH at reflux, a cyclization occurred to give the corresponding 1,2,4‐triazole‐3‐selone 9b. Again, the same product was formed when a mixture of 4b and 6b was heated in MeOH. Surprisingly, analogous cyclizations of selenosemicarbazides of type 5 under the same conditions failed, and only decomposition was observed. The structures of 7a, 7d, and 9b have been established by X‐ray crystallography.
Enantiomer‐specific profenofos‐induced cytotoxicity and DNA damage mediated by oxidative stress in rat adrenal pheochromocytoma (PC12) cells
Authors: Lu Xianting , Yu Cheng 
Published: March 2013

ABSTRACTRecent studies have shown that chiral pesticides could enantioselectively induce cytotoxicity and genotoxicity. However, investigations on molecular mechanisms of enantioselective toxicity of pesticides are limited. In this study, the role of oxidative stress in enantiomer‐specific, profenofos (PFF)‐induced cytotoxicity and genotoxicity was investigated using PC12 cells. The results demonstrated that PFF enantioselectively reduced cell viability and induced DNA damage in PC12 cells. A concentration‐ and time‐dependent significant induction of reactive oxygen species (ROS), malondialdehyde and gene expression encoding antioxidant enzyme (Cu‐ZnSOD, GST and CAT) and stress protein (HSP 70 and HSP 90) was observed in (−)­PFF, whereas (+)­PFF and rac‐PFF exhibited these effects to lesser degrees. Pre‐treatment with vitamin E (600 μM) caused a significant attenuation in the toxic effect; reversing subsequent PFF‐induced elevation of ROS and malondialdehyde (MDA) levels, further strengthening the involvement of oxidative stress in PFF‐mediated toxicity. In addition, the results also showed that PFF‐dependent ROS accumulation, MDA release and oxidative stress gene expression preceded the loss of cell viability and induction of DNA damage, and already significantly changed at concentrations which are not yet cytotoxic or genotoxic. These results indicate that oxidative stress may contribute to PFF‐induced toxicity and that it was not a consequence of it. Copyright © 2013 John Wiley & Sons, Ltd.
Multispectral fluorescence lifetime imaging system for intravascular diagnostics with ultrasound guidance: in vivo validation in swine arteries
Authors: Bec Julien , Ma Dinglong M. , Yankelevich Diego R. , Liu Jing , Ferrier William T. , Southard Jeffrey , Marcu Laura 
Published: March 2013

AbstractFluorescence lifetime technique has demonstrated potential for analysis of atherosclerotic lesions and for complementing existing intravascular imaging modalities such as intravascular ultrasound (IVUS) in identifying lesions at high risk of rupture. This study presents a multimodal catheter system integrating a 40 MHz commercial IVUS and fluorescence lifetime imaging (FLIm) using fast helical motion scanning (400 rpm, 0.75 mm/s), able to acquire in vivo in pulsatile blood flow the autofluorescence emission of arterial vessels with high precision (5.08 ± 0.26 ns mean average lifetime over 13 scans). Co‐registered FLIm and IVUS data allowed 3D visualization of both biochemical and morphological vessel properties. Current study supports the development of clinically compatible intravascular diagnostic system integrating FLIm and demonstrates, to our knowledge, the first in vivo intravascular application of a fluorescence lifetime imaging technique. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Architecture of the osteocyte network correlates with bone material quality
Authors: Kerschnitzki Michael , Kollmannsberger Philip , Burghammer Manfred , Duda Georg N , Weinkamer Richard , Wagermaier Wolfgang , Fratzl Peter 
Published: March 2013

ABSTRACT

In biological tissues such as bone, cell function and activity crucially depend on the physical properties of the extracellular matrix which the cells synthesize and condition. During bone formation and remodeling, osteoblasts get embedded into the matrix they deposit and differentiate to osteocytes. These cells form a dense network throughout the entire bone material. Osteocytes are known to orchestrate bone remodeling. However, the precise role of osteocytes during mineral homeostasis and their potential influence on bone material quality remains unclear. To understand the mutual influence of osteocytes and extracellular matrix, it is crucial to reveal their network organization in relation to the properties of their surrounding material. Here we visualize and topologically quantify the osteocyte network in mineralized bone sections with confocal laser scanning microscopy. At the same region of the sample, synchrotron small-angle X-ray scattering is used to determine nanoscopic bone mineral particle size and arrangement relative to the cell network. Major findings are that most of the mineral particles reside within less than a micrometer from the nearest cell network channel and that mineral particle characteristics depend on the distance from the cell network. The architecture of the network reveals optimization with respect to transport costs between cells and to blood vessels. In conclusion, these findings quantitatively show that the osteocyte network provides access to a huge mineral reservoir in bone due to its dense organization. The observed correlation between the architecture of osteocyte networks and bone material properties supports the hypothesis that osteocytes interact with their mineralized vicinity and thus, participate in bone mineral homeostasis.
Expression and function of K(ATP) channels in normal and osteoarthritic human chondrocytes: Possible role in glucose sensing
Authors: Rufino Ana T. , Rosa Susana C. , Judas Fernando , Mobasheri Ali , Lopes M. Celeste , Mendes Alexandrina F. 
Published: March 2013

AbstractATP‐sensitive potassium [K(ATP)] channels sense intracellular ATP/ADP levels, being essential components of a glucose‐sensing apparatus in various cells that couples glucose metabolism, intracellular ATP/ADP levels and membrane potential. These channels are present in human chondrocytes, but their subunit composition and functions are unknown. This study aimed at elucidating the subunit composition of K(ATP) channels expressed in human chondrocytes and determining whether they play a role in regulating the abundance of major glucose transporters, GLUT‐1 and GLUT‐3, and glucose transport capacity. The results obtained show that human chondrocytes express the pore forming subunits, Kir6.1 and Kir6.2, at the mRNA and protein levels and the regulatory sulfonylurea receptor (SUR) subunits, SUR2A and SUR2B, but not SUR1. The expression of these subunits was no affected by culture under hyperglycemia‐like conditions. Functional impairment of the channel activity, using a SUR blocker (glibenclamide 10 or 20 nM), reduced the protein levels of GLUT‐1 and GLUT‐3 by approximately 30% in normal chondrocytes, while in cells from cartilage with increasing osteoarthritic (OA) grade no changes were observed. Glucose transport capacity, however, was not affected in normal or OA chondrocytes. These results show that K(ATP) channel activity regulates the abundance of GLUT‐1 and GLUT‐3, although other mechanisms are involved in regulating the overall glucose transport capacity of human chondrocytes. Therefore, K(ATP) channels are potential components of a broad glucose sensing apparatus that modulates glucose transporters and allows human chondrocytes to adjust to varying extracellular glucose concentrations. This function of K(ATP) channels seems to be impaired in OA chondrocytes. J. Cell. Biochem. 114: 1879–1889, 2013. © 2013 Wiley Periodicals, Inc.
Regulation of selective PPARγ modulators in the differentiation of osteoclasts
Authors: Wu Haochen , Li Long , Ma Yong , Chen Yongjun , Zhao Jingfa , Lu Yan , Shen Pingping 
Published: March 2013

AbstractDiabetes is the most common chronic disease in the world and causes complications with many diseases, such as heart disease and osteoporosis. Osteoporosis is a systemic bone disease characterized by imbalance in bone resorption and bone formation. Osteoclast is type of bone cell that functions in bone resorption and plays a critical role in bone remodeling. Rosiglitazone and pioglitazone, which belong to Thiazolidinediones(TZDs), are commonly used antidiabetic drugs. As PPARγ full agonists, they can activate PPARγ in a ligand‐dependent way. Recent studies indicate that these PPARγ full agonists have some side effects, such as weight gain and bone loss, which may increase the risk of osteoporosis. In contrast, selective PPARγ Modulators (SPPARγMs) are novel PPARγ ligands that can activate PPARγ in different ways and lead to distinct downstream genes. Mice bone marrow cells were stimulated with recombinant mouse RANKL and M‐CSF to generate osteoclasts. To determine the effect on osteoclasts formation, PPARγ ligands (Rosiglitazone, Fmoc‐L‐Leu, and Telmisartan) were added at the beginning of the culture. Rosiglitazone significantly increased the differentiation of multinucleated osteoclasts, while osteoclasts formation triggered by SPPARγMs was much less than that displayed by rosiglitazone. We found that the enhancement of PPARγ ligands may be associated with TRAF6 and downstream ERK signal pathway. We also demonstrated osteoclasts show characteristic M2 phenotype and can be further promoted by PPARγ ligands, especially rosiglitazone. In conclusion, reduced osteoclasts differentiation characteristic of SPPARγMs highlights SPPARγMs potential as therapeutic targets in diabetes, versus traditional antidiabetic drugs. J. Cell. Biochem. 114: 1969–1977, 2013. © 2013 Wiley Periodicals, Inc.
Sclerostin is expressed in osteoclasts from aged mice and reduces osteoclast‐mediated stimulation of mineralization
Authors: Ota Kuniaki , Quint Patrick , Ruan Ming , Pederson Larry , Westendorf Jennifer J. , Khosla Sundeep , Oursler Merry Jo 
Published: March 2013

AbstractOsteoclast‐mediated bone resorption precedes osteoblast‐mediated bone formation through early adulthood, but formation fails to keep pace with resorption during aging. We previously identified several factors produced by osteoclasts that promote bone formation. In this study, we determined if osteoclast‐produced factors contribute to the impaired bone formation with aging. We previously found that mice between the ages of 18 and 22 months develop age‐related bone loss. Bone marrow‐derived pre‐osteoclasts were isolated from 6‐week, 12‐month, and 18‐ to 24‐month‐old mice and differentiated into osteoclasts in vitro. Conditioned media were collected and compared for osteoblast mineralization support. Conditioned medium from osteoclasts from all ages was able to support mineralization of bone marrow stromal cells. Concentrating the conditioned medium from 6‐week‐old and 12‐month‐old mouse marrow cells‐derived osteoclasts enhanced mineralization support whereas concentrated conditioned medium from 18‐ to 24‐month‐old mouse marrow‐derived osteoclasts repressed mineralization compared to base medium. This observation suggests that an inhibitor of mineralization was secreted by aged murine osteoclasts. Gene and protein analysis revealed that the Wnt antagonist sclerostin was significantly elevated in the conditioned media from 24‐month‐old mouse cells compared to 6‐week‐old mouse cells. Antibodies directed to sclerostin neutralized the influences of the aged mouse cell concentrated conditioned media on mineralization. Sclerostin is primarily produced by osteocytes in young animals. This study demonstrates that osteoclasts from aged mice also produce sclerostin in quantities that may contribute to the age‐related impairment in bone formation. J. Cell. Biochem. 114: 1901–1907, 2013. © 2013 Wiley Periodicals, Inc.
Mechanisms of ceramide‐induced COX‐2‐dependent apoptosis in human ovarian cancer OVCAR‐3 cells partially overlapped with resveratrol
Authors: Lin Hung‐Yun , Delmas Dominique , Vang Ole , Hsieh Tze‐Chen , Lin Sharon , Cheng Guei‐Yun , Chiang Hsiao‐Ling , Chen Chiao En , Tang Heng‐Yuan , Crawford Dana R. , Whang‐Peng Jacqueline , Hwang Jaulang , Liu Leroy F. , Wu Joseph M. 
Published: March 2013

AbstractCeramide is a member of the sphingolipid family of bioactive molecules demonstrated to have profound, diverse biological activities. Ceramide is a potential chemotherapeutic agent via the induction of apoptosis. Exposure to ceramide activates extracellular‐signal‐regulated kinases (ERK)1/2‐ and p38 kinase‐dependent apoptosis in human ovarian cancer OVCAR‐3 cells, concomitant with an increase in the expression of COX‐2 and p53 phosphorylation. Blockade of cyclooxygenase‐2 (COX‐2) activity by siRNA or NS398 correspondingly inhibited ceramide‐induced p53 Ser‐15 phosphorylation and apoptosis; thus COX‐2 appears at the apex of the p38 kinase‐mediated signaling cascade induced by ceramide. Induction of apoptosis by ceramide or resveratrol was inhibited by the endocytosis inhibitor, cytochalasin D (CytD); however, cells exposed to resveratrol showed greater sensitivity than ceramide‐treated cells. Ceramide‐treated cells underwent a dose‐dependent reduction in trans‐membrane potential. Although both ceramide and resveratrol induced the expressions of caspase‐3 and ‐7, the effect of inducible COX‐2 was different in caspase‐7 expression induced by ceramide compared to resveratrol. In summary, resveratrol and ceramide converge on an endocytosis‐requiring, ERK1/2‐dependent signal transduction pathway and induction of COX‐expression as an essential molecular antecedent for subsequent p53‐dependent apoptosis. In addition, expressions of caspase‐3 and ‐7 are observed. However, a p38 kinase‐dependent signal transduction pathway and change in mitochondrial potential are also involved in ceramide‐induced apoptosis. J. Cell. Biochem. 114: 1940–1954, 2013. © 2013 Wiley Periodicals, Inc.
Modeling in Engineering: The Role of Representational Fluency in Students' Conceptual Understanding
Authors: Moore Tamara J. , Miller Ronald L. , Lesh Richard A. , Stohlmann Micah S. , Kim Young Rae 
Published: March 2013

AbstractBackgroundModeling abilities play an important role in engineering. The creation and use of representations is a central aspect of modeling, and students who are learning to model often use a variety of representations to express, test, revise, and communicate their own thinking. Consequently, model development often depends on representational fluency and the ability to translate between and within different representational forms.PurposeThis study investigates the role that representations and representational fluency play in conceptual understanding during a complex modeling task related to heat transfer.Design/MethodThis study involved 16 teams of 3 or 4 college students in a first‐semester heat transfer course participating in a complex modeling task. The task of the student teams was to develop a model to predict the interface temperature and the sensation felt by human skin when touching a utensil made of a given material at a given temperature. Data sources included audio recordings of student teams, as well as student‐generated artifacts.ResultsThe results show teams thinking about their model through multiple representations and through translations within and among representations. Students' early ways of thinking used a variety of interacting representations but were often unstable and involved incomplete notions of the system to be modeled. Model development involved increasing representational fluency as well as parallel and interacting progress along a variety of dimensions.ConclusionsThis study furthers the understanding of representational fluency in undergraduate engineering students in a heat transfer setting and how representational fluency contributes to conceptual and application understanding.