bluuebunny/crossref_metadata_2025_split huggingface dataset:
Malonylated Glycerolipids from the Glandular Trichome Exudate of Ceratotheca triloba
Authors: Ohkawa Akiko , Sakai Takaomi , Ohyama Kiyoshi , Fujimoto Yoshinori 
Published: August 2012

AbstractChemical investigation of the glandular trichome exudate from Ceratotheca triloba (Pedaliaceae) led to the identification of nine 1‐O‐acetyl‐2‐O‐[(R)‐3‐acetyloxy‐fatty acyl]‐3‐O‐malonylglycerols. Among these, 1‐O‐acetyl‐2‐O‐[(R)‐3‐acetyloxyicosanoyl]‐3‐O‐malonylglycerol (7) was the most abundant constituent (41%), followed by 1‐O‐acetyl‐2‐O‐[(R)‐(3‐acetyloxyoctadecanoyl)‐3‐O‐malonylglycerol (2; 21%). Compounds having iso‐ and anteiso‐type structures in the 3‐acetyloxy‐fatty acyl groups in the fatty acyl moiety were also characterized as minor constituents. This is the first report of the isolation of malonylated glycerolipids as natural products.
On CO Egress from, and Re‐Uptake by, the Enzyme MauG, as a Mimic of the Acquisition of Oxidizing Agents by the pre‐MADH_MauG System. A Molecular Mechanics Approach
Authors: Pietra Francesco 
Published: August 2012

AbstractIn this work, by applying a non‐deterministic, randomly‐oriented minimal force to the dissociated CO ligand of the MauG‐CO system, the molecular‐dynamics (MD) behavior of this system could be quickly unraveled. It turned out that CO has no marked directional egress from the high‐spin c‐heme iron distal pocket. Rather, CO is able to exploit all interstices created during the protein fluctuations. Nonetheless, no steady route toward the surrounding solvent was ever observed: CO jumped first into other binding pockets before being able to escape the protein. In a few cases, on hitting the surrounding H2O molecules, CO was observed to reverse direction, re‐entering the protein. A contention that conformational inversion of the P107 ring provides a gate to the iron ion is not supported by the present simulations.
Influence of the antiscatter grid on dose and image quality in pediatric interventional cardiology X‐ray systems
Authors: Ubeda Carlos , Vano Eliseo , Gonzalez Luciano , Miranda Patricia 
Published: August 2012

ObjectiveTo present a methodology and experimental results to assess the influence, in terms of dose and image quality, of the antiscatter grid (AG) in a pediatric cardiology X‐ray system.MethodEntrance surface air kerma and image quality, using a test object and different added thicknesses of polymethyl methacrylate (PMMA), for three different acquisition protocols, were measured with and without the AG, for fluoroscopy and cine modes. The image quality parameters, signal‐to‐noise ratio (SNR), high‐contrast spatial resolution (HCSR) and two figures of merit (FOM) were evaluated.ResultsThe average bucky factor values measured during this experiment were 1.99, 2.49, 2.85, and 3.30, respectively for 4, 8, 12, and 16 cm of PMMA. SNR variations do not appear to be relevant when removing the AG. However, the use of AG improves HCSR significantly. Imaging the test object with 4 cm of PMMA seems appropriate without the AG, but for 8 cm (equivalent to chest thicknesses of 12 cm) and greater thicknesses, a good image quality would require the use of AG.ConclusionsThe AG should not be used for neonates and very young children with chest thicknesses equal to or less than 6 cm and weight less that 6 kg. © 2013 Wiley Periodicals, Inc.
Differential long‐term outcomes of zotarolimus‐eluting stents compared with sirolimus‐eluting and paclitaxel‐eluting stents in diabetic and nondiabetic patients: Two‐year subgroup analysis of the ZEST randomized trial
Authors: Jang Sun‐Joo , Park Duk‐Woo , Kim Won‐Jang , Kim Young‐Hak , Yun Sung‐Cheol , Kang Soo‐Jin , Lee Seung‐Whan , Lee Cheol Whan , Park Seong‐Wook , Park Seung‐Jung 
Published: August 2012

ObjectivesTo evaluate the differential treatment effects of zotarolimus‐eluting stents (ZES), sirolimus‐eluting stents (SES), and paclitaxel‐eluting stents (PES) according to diabetic status.BackgroundDiabetic patients have a higher risk of ischemic complications after stenting than nondiabetic patients.MethodsUsing data from the ZEST randomized trial, comparing ZES with SES and PES, we evaluated relative outcomes among stents in diabetic and nondiabetic patients. The primary outcome was a major adverse cardiac event (MACE), defined as a composite of death, myocardial infarction, or ischemia‐driven target‐vessel revascularization.ResultsOf the 2,645 patients enrolled in the ZEST trial, 760 (29%) had diabetes mellitus. Baseline clinical and angiographic characteristics were similar in the three stent groups, regardless of diabetic status. In diabetic patients, ZES showed similar rates of MACE as compared to PES (13.8% vs. 15.3%, P = 0.58), but higher rates of MACE than SES (13.8% vs. 7.7%, P = 0.05). In nondiabetic patients, ZES showed similar rates of MACE as compared to SES (10.3% vs. 10.8%, P = 0.72), whereas significantly lower rates of MACE compared to PES (10.3% vs. 15.3%, P = 0.01). In comparing the ZES and SES groups, there was a substantial interaction between diabetic status and stent types on MACE occurrence (Interaction P = 0.07). However, in comparison of ZES and PES, there were no significant interactions between diabetes and stent type on MACE (Interaction P = 0.25).ConclusionsIn diabetic patients, SES showed the lowest rate of MACE compared with ZES and PES. But, in nondiabetic patients, SES and ZES showed significantly lower rates of MACE than PES. ZES shows a diabetes‐related interaction on MACE compared with SES, but not with PES. © 2012 Wiley Periodicals, Inc.
Reading of Protein Surfaces in the Native State at Micromolar Concentrations by a Chirogenetic Porphyrin Probe
Authors: Mineo Placido , Micali Norberto , Villari Valentina , Donato Maria Grazia , Scamporrino Emilio 
Published: August 2012

AbstractThe recognition of some globular proteins was carried out in aqueous solution, at micromolar concentrations, by using an uncharged symmetrical cobalt–porphyrin (Co–P). By means of UV/Vis, induced circular dichroism, and fluorescence spectroscopy techniques, it was ascertained that the interactions between specific amino acid residues and Co–P occurred on the protein surface. In particular, spectroscopic evidence showed the formation of supramolecular complexes without disruption of the native structure of the proteins and, furthermore, that signal changes were characteristic of each Co–P/protein system, so that they could be used as a highly sensitive analytical tool for protein recognition. The relative association constants were proportional to the protein molecular masses (and then to the number of amino acid residues).
Anticancer Activity of Hydrogen‐Bond‐Stabilized Half‐Sandwich RuII Complexes with Heterocycles
Authors: Mitra Raja , Das Sangeeta , Shinde Sridevi V. , Sinha Sarika , Somasundaram Kumaravel , Samuelson Ashoka G. 
Published: August 2012

AbstractNeutral half‐sandwich organometallic ruthenium(II) complexes of the type [(η6‐cymene)RuCl2(L)] (H1–H10), where L represents a heterocyclic ligand, have been synthesized and characterized spectroscopically. The structures of five complexes were also established by single‐crystal X‐ray diffraction confirming a piano‐stool geometry with η6 coordination of the arene ligand. Hydrogen bonding between the NH group of the heterocycle and a chlorine atom attached to Ru stabilizes the metal–ligand interaction. Complexes coordinated to a mercaptobenzothiazole framework (H1) or mercaptobenzoxazole (H6) showed high cytotoxicity against several cancer cells but not against normal cells. In vitro studies have shown that the inhibition of cancer cell growth involves primarily G1‐phase arrest as well as the generation of reactive oxygen species (ROS). The complexes are found to bind DNA in a non‐intercalative fashion and cause unwinding of plasmid DNA in a cell‐free medium. Surprisingly, the cytotoxic complexes H1 and H6 differ in their interaction with DNA, as observed by biophysical studies, they either cause a biphasic melting of the DNA or the inhibition of topoisomerase IIα activity, respectively. Substitution of the aromatic ring of the heterocycle or adding a second hydrogen‐bond donor on the heterocycle reduces the cytotoxicity.
Identification and characterization of a novel myosin Ic isoform that localizes to the nucleus
Authors: Ihnatovych Ivanna , Migocka‐Patrzalek Marta , Dukh Mykhaylo , Hofmann Wilma A. 
Published: August 2012

AbstractIn vertebrates, two myosin Ic isoforms that localize to the cytoplasm and to the nucleus have been characterized. The isoform that predominantly localizes to the nucleus is called nuclear myosin I (NMI). NMI has been identified as a key factor involved in nuclear processes such as transcription by RNA polymerases I and II and intranuclear transport processes. We report here the identification of a previously uncharacterized third MYOIC gene product that is called isoform A. Similar to NMI, this isoform contains a unique N‐terminal peptide sequence, localizes to the nucleus and colocalizes with RNA polymerase II. However, unlike NMI, upon exposure to inhibitors of RNA polymerase II transcription the newly identified isoform translocates to nuclear speckles. Furthermore, in contrast to NMI, this new isoform is absent from nucleoli and does not colocalize with RNA polymerase I. Our results suggest an unexpected diversity among nuclear myosin Ic isoforms in respect to their intranuclear localization and interaction with nuclear binding partners that could provide new insights into the regulation of myosin‐dependent nuclear processes. © 2012 Wiley Periodicals, Inc.
Novel actin rings within the secretory cells of honeybee royal jelly glands
Authors: Kheyri Homayoun , Cribb Bronwen W. , Reinhard Judith , Claudianos Charles , Merritt David J. 
Published: August 2012

AbstractWe describe a novel cytoskeletal element within secretory cells of an arthropod gland system, the hypopharyngeal gland of the honeybee, Apis mellifera. The hypopharyngeal secretory cells are the source of royal jelly in nurse bees and enzymes in foragers. Each cell possesses an elongate invagination that is occupied by a tubular cuticular structure, the end‐apparatus, that accumulates secretion and transfers it into a cuticular microtube and then into a collecting duct. Within the secretory cell, a conspicuous series of actin rings, about 3 μm in diameter, follows the same path as the end‐apparatus, surrounding it at spaced intervals. Transmission electron microscopy confirmed that the actin rings lie within septa of the secretory cell that are closely juxtaposed to the end‐apparatus at regularly spaced intervals. We speculate that the function of the actin rings is to hold the end apparatus in place as secretion swells the extracellular compartments between the end apparatus and the cell membrane. To our knowledge, no such cytoskeletal component has been described in animal cells. © 2012 Wiley Periodicals, Inc
A fairness adaptive TDMA scheduling algorithm for wireless sensor networks with unreliable links
Authors: Wang Zhiqi , Yu Fengqi , Tian Jian , Zhang Zusheng 
Published: August 2012

SUMMARYWireless sensor networks consist of a large number of wireless sensor nodes that organize themselves into multihop radio networks. With different link quality, different distance to the sink, nodes in a network are not treated equally, especially in a network with high traffic. In this paper, we propose a fairness adaptive time division multiple access scheduling algorithm (FATS) considering the fairness of network resource allocation. This algorithm, combining several heuristic algorithms, can assign network resources to the nodes to lead to maximizing the minimum end‐to‐end packet delivery success ratio. Because the wireless link is usually time‐varying, this algorithm can also assign the time slots to the nodes adaptively and energy‐efficiently according to the variation of link quality. We define several criteria for the slot assignment and adjustment. The change in slot assignment can be finished quickly during normal packet transmission, which causes little affect to the network. Meanwhile, considering the required data rate, FATS can achieve the maximum transmission capacity of the network with specified static or dynamic reliability. The simulation results show that the FATS can significantly reduce the difference of the end‐to‐end packet delivery ratio, track the variation of link quality quickly, and achieve the fairness of resource allocation.Copyright © 2012 John Wiley & Sons, Ltd.
Jointly optimizing sensing time and resource allocation in multichannel cognitive radio networks
Authors: Li Li , Xu Changqing , He Jian 
Published: August 2012

SUMMARYSpectrum sensing is a key technique for determining the spectrum available in cognitive radio (CR) networks. In this paper, we study how to jointly optimize sensing time and resource allocation to maximize the sum transmission rate of all CR users of a multichannel CR network. We take into consideration the transmission power and interference constraints to protect primary users from harmful interference, as well as constraints of detection probability and false alarm probability. Under these constraints, we propose an asymptotically optimal resource allocation algorithm. The optimal sensing time can be obtained using the traditional one‐dimensional exhaustive search. However, owing to the high complexity of searching for the sensing time, we propose a simplified method to get the optimal sensing time under the assumption that false alarm probability is small. Simulation results show that the simplified method can obtain the optimal sensing time efficiently under strict constraint of false alarm probability. Copyright © 2012 John Wiley & Sons, Ltd.
A bandwidth allocation algorithm with channel quality and QoS aware for IEEE 802.16 base stations
Authors: Yeh Yi‐Hsuan , Lai Yuan‐Cheng , Chen Yen‐Hung , Lai Ching‐Neng 
Published: August 2012

SUMMARYSubscriber stations located in different places encounter various interferences in an IEEE 802.16 network, resulting in that their communication channels experience varying channel conditions. Thus, an excellent bandwidth allocation algorithm should not only satisfy various QoS required by heterogeneous traffic, but also consider the channel quality to maximize bandwidth utilization. In this paper, a bandwidth allocation algorithm with channel quality awareness and QoS guarantee, called CQQ, is proposed. CQQ not only satisfies each connection's QoS requirement, but also dynamically adjusts the downlink/uplink bandwidth to match current downlink/uplink traffic ratio. CQQ allocates more bandwidth to the connections having better channel quality by applying weighted fair queuing strategy to raise the bandwidth usage. CQQ provides lower delay violation ratio and higher goodput than the previous algorithms, as observed from the simulation results. Copyright © 2012 John Wiley & Sons, Ltd.
Recurrent subcutaneous emphysema as a consequence of bulimia nervosa
Authors: McCurdy John M. , McKenzie Courtney E. , El‐Mallakh Rif S. 
Published: August 2012

AbstractObjective:Pneumomediastinum is a rare complica‐tion of increased intrathoracic pressure. It is more likely to occur in individuals with nutritional deficiencies. Pneumomediastinum has been reported in some individuals with anorexia nervosa.Method:Case report.Results:Recurrent subcutaneous emphysema is probably secondary to recurrent pneumomediastinum in a woman with bulimia nervosa.Discussion:It is believed that increased intrathoracic pressure and nutritional deficiency associated with repeated induced vomiting contributed to this complication. This is the only case of recurrent subcutaneous emphysema. While in this case, and in most cases, the course was benign with eventual reabsorption of the subcutaneous air, pneumomediastinum can be a life‐threatening complication of bulimia nervosa. © 2012 by Wiley Periodicals, Inc. (Int J Eat Disord 2013)
Three‐Component, One‐Pot Sequential Synthesis of Tetracyclic Pyrido[2′,1′:2,3]imidazo[5,1‐a]isoquinolinium Compounds as Potent Anticancer Agents
Authors: Zhou Huayong , Wang Wei , Khorev Oleg , Zhang Yongliang , Miao Zehong , Meng Tao , Shen Jingkang 
Published: August 2012

AbstractA new practical method for the synthesis of tetracyclic pyrido[2′,1′:2,3]imidazo[5,1‐a]isoquinolinium compounds by a Yb(OTf)3/AgOTf‐catalyzed (Tf = triflate) three‐component domino reaction was developed. Significantly, the strategy presents a straightforward and efficient approach to constructing a series of compounds with potent cytotoxic activities.
Discovery of a Robust and Efficient Homogeneous Silver(I) Catalyst for the Cycloaddition of Azides onto Terminal Alkynes
Authors: McNulty James , Keskar Kunal 
Published: August 2012

AbstractA highly efficient, chemically stable, and well‐defined homogeneous silver(I) catalyst is reported for the cycloaddition of azides onto terminal alkynes (Ag‐AAC reaction). The Ag‐AAC reaction occurs at room temperature or with heating to deliver exclusively the corresponding 1,4‐triazole. A pronounced ligand effect was discovered through systematic modification to the ligand structure resulting in the discovery of a chemically stable active catalyst for this reaction.
Modeling of a large‐scale magneto‐rheological damper for seismic hazard mitigation. Part I: Passive mode
Authors: Chae Yunbyeong , Ricles James M. , Sause Richard 
Published: August 2012

SUMMARYMagneto‐rheological (MR) dampers are a promising device for seismic hazard mitigation because their damping characteristics can be varied adaptively using an appropriate control law. During the last few decades researchers have investigated the behavior of MR dampers and semi‐active control laws associated with these types of dampers for earthquake hazard mitigation. A majority of this research has involved small‐scale MR dampers. To investigate the dynamic behavior of a large‐scale MR damper, characterization tests were conducted at the Lehigh Network for Earthquake Engineering Simulation equipment site on large‐scale MR dampers. A new MR damper model, called the Maxwell Nonlinear Slider (MNS) model, is developed based on the characterization tests and is reported in this paper. The MNS model can independently describe the pre‐yield and post‐yield behavior of an MR damper, which makes it easy to identify the model parameters. The MNS model utilizes Hershel–Bulkley visco‐plasticity to describe the post‐yield non‐Newtonian fluid behavior, that is, shear thinning and thickening behavior, of the MR fluid that occurs in the dampers. The predicted response of a large‐scale damper from the MNS model along with that from existing Bouc–Wen and hyperbolic tangent models, are compared with measured response from various experiments. The comparisons show that the MNS model achieves better accuracy than the existing models in predicting damper response under cyclic loading. Copyright © 2012 John Wiley & Sons, Ltd.
Effectiveness of superelastic bars for seismic rehabilitation of clay‐unit masonry walls
Authors: Shrestha Kshitij C. , Araki Yoshikazu , Nagae Takuya , Omori Toshihiro , Sutou Yuji , Kainuma Ryosuke , Ishida Kiyohito 
Published: August 2012

SUMMARYThis paper presents the results on shaking table tests of half‐scale brick walls performed to investigate the effectiveness of newly developed Cu–Al–Mn superelastic alloy (SEA) bars in retrofitting of historical masonry constructions. Problems associated with conventional steel reinforcing bars lie in degradation of stiffness and strength, or pinching phenomena, under cyclic loading, and presence of large residual cracks in structures during and after intense earthquakes. This paper attempts to resolve the problems by applying newly developed Cu–Al–Mn SEA bars, characterized by large recovery strain, low material cost, and high machinability, as partial replacements for steel bars. Sets of unreinforced, steel reinforced, and SEA‐reinforced specimens are subjected to scaled earthquake excitations in out‐of‐plane direction. Whereas steel‐reinforced specimens showed large residual inclinations, SEA‐reinforced specimens resulted in stable rocking response with slight residual inclinations. Corresponding nonlinear finite element (FE) models are developed to simulate the experimental observations. The FE models are further used to examine the sensitivity of the response with respect to the variations in experimental conditions. Both the experimental and numerical results demonstrate the superiority of Cu–Al–Mn SEA bars to conventional steel reinforcing bars in avoiding pinching phenomena. Copyright © 2012 John Wiley & Sons, Ltd.
How do aquatic communities respond to contaminants? It depends on the ecological context
Authors: Clements William H. , Hickey Chris W. , Kidd Karen A. 
Published: August 2012

Abstract
Context dependency refers to variation in ecological patterns and processes across environmental or spatiotemporal gradients. Research on context dependency in basic ecology has focused primarily on variation in the relative importance of species interactions (e.g., competition and predation) among communities. In this Focus article, the authors extend this concept to include variation in responses of communities to contaminants and other anthropogenic stressors. Because the structure of communities varies naturally along environmental gradients, their responses to contaminants may also vary. Similar to the way in which aquatic toxicologists assess abiotic factors associated with contaminant bioavailability, observations about context dependency could be used to test hypotheses about ecological mechanisms responsible for differences in sensitivity among communities. Environ. Toxicol. Chem. 2012; 31: 1932–1940. © 2012 SETAC
Recovery of photosynthesis and growth rate in green, blue–green, and diatom algae after exposure to atrazine
Authors: Brain Richard A. , Arnie Joshua R. , Porch John R. , Hosmer Alan J. 
Published: August 2012

Abstract
We evaluated the recovery of photosynthesis and growth rate in green (Pseudokirchneriella subcapitata), blue-green (Anabaena flos-aquae), and diatom (Navicula pelliculosa) algae after pulsed exposure to atrazine. Subsequent to a grow-up period of 24 to 72 h to establish requisite cell density for adequate signal strength to measure photosystem II (PSII) quantum yield, algae were exposed to a pulse of atrazine for 48 h followed by a 48-h recovery period in control media. Photosynthesis was measured at 0, 3, 6, 12, 24, and 48 h of the exposure and recovery phases using pulse amplitude modulation fluorometry; growth rate and cell density were also concomitantly measured at these time points. Exposure to atrazine resulted in immediate, but temporary, inhibition of photosynthesis and growth; however, these effects were transient and fully reversible in the tested species of algae. For all three algal species, no statistically significant reductions (p ≤ 0.05) in growth rate or PSII quantum yield were detected at any of the treatment concentrations 48 h after atrazine was removed from the test system. Effects at test levels up to the highest tested exposure levels were consequently determined to be algistatic (reversible). Both biochemically and physiologically, recovery of photosynthesis and growth rate occur immediately, reaching control levels within hours following exposure. Therefore, pulsed exposure profiles of atrazine typically measured in Midwestern U.S. streams are unlikely to result in biologically meaningful changes in primary production given that the effects of atrazine are temporary and fully reversible in species representative of native populations. Environ. Toxicol. Chem. 2012; 31: 2572–2581. © 2012 SETAC