bluuebunny/crossref_metadata_2025_split huggingface dataset:
Microarray analysis of cellular thermotolerance
Authors: Beckham Josh T. , Wilmink Gerald J. , Opalenik Susan R. , Mackanos Mark A. , Abraham Alex A. , Takahashi Keiko , Contag Chris H. , Takahashi Takamune , Jansen E. Duco 
Published: January 2011

AbstractBackground and ObjectivesPreviously, we have shown that a 43°C pretreatment can provide thermotolerance to a following, more severe, thermal stress at 45°C. Using cells that lack the Hsp70 gene, we have also shown that there is still some thermotolerance in the absence of HSP70 protein. The purpose of this study was to determine which genes play a role in thermotolerance by measuring viability and proliferation of the cells at 2 days after heating. Specifically, we wanted to understand which pathways may be responsible for protecting cells in the absence of HSP70.Study Design/Materials and MethodsMurine embryonic fibroblast cells with and without Hsp70 (MEF(+/+) and MEF(−/−), respectively) were exposed to a mild heat shock of 43°C for 30 minutes in a constant temperature water bath. After 3 hours of recovery, RNA was harvested from three heated samples alongside three untreated controls using a MicroRNeasy kit with DNAse treatment. RNA quality was verified by an Agilent Bioanalyzer. The RNA was then converted to cDNA and hybridized to Affymetrix gene expression DNA microarrays. The genes that showed a twofold change (up or down) relative to unheated controls were filtered by t‐test for significance at a threshold of P < 0.05 using Genespring software. Data were verified by qRT‐PCR. Genes were then categorized based upon their ontology.ResultsWhile many genes were similarly upregulated, the main difference between cell types was an increase in transcription factors and nucleic acid binding proteins. Several genes known to be involved in the heat response were upregulated more than twofold (Hsp70, Hsp40, Hsp110, Hsp25, Atf3), however, another well studied heat responsive gene Hsp90 only increased by 1.5‐fold under these conditions despite its role in thermotolerance.ConclusionsThe data herein presents genetic pathways which are candidates for further study of pretreatment protocols in laser irradiation. Lasers Surg. Med. 42:912–925, 2010. © 2010 Wiley‐Liss, Inc.
The fidelity of spin trapping with DMPO in biological systems
Authors: Ranguelova Kalina , Mason Ronald P. 
Published: January 2011

AbstractUnlike direct ESR, spin trap methodology depends on the absolute fidelity of the spin trap reaction. Two alternative reactions of 5,5‐dimethyl‐1‐pyrrolineN‐oxide (DMPO) leading to radical adduct artifacts have been discovered and investigated: inverted spin trapping and the Forrester–Hepburn nucleophilic mechanism. These two alternate pathways to radical adducts are a combination of one‐electron oxidation and nucleophilic addition, in either order. In biological systems, serious artifacts have been reported due to the Forrester–Hepburn mechanism, which is initiated by the addition of a nucleophile to DMPO. It has recently been demonstrated that (bi)sulfite (hydrated sulfur dioxide) can react with DMPO via a nonradical, nucleophilic reaction, and it has been further proposed that DMPO/•SO3−formation in biological systems is an artifact and not the result of spin trapping of sulfur trioxide anion radical (•SO3−). The one‐electron oxidation of (bi)sulfite catalyzed by horseradish peroxidase (HRP)/hydrogen peroxide (H2O2) has been reinvestigated by ESR spin trapping with DMPO and oxygen uptake studies to obtain further evidence for the radical reaction mechanism. In the absence of DMPO, the initial rate of (bi)sulfite‐dependent oxygen and H2O2consumption was determined to be half of the initial rate of DMPO/•SO3−radical adduct formation as determined by ESR, demonstrating that, under our experimental conditions, DMPO exclusively forms the radical adduct by trapping the•SO3−. Copyright © 2011 John Wiley & Sons, Ltd.
A CW‐EPR, ENDOR and special TRIPLE resonance study of a novel magnesium ketyl radical
Authors: Murphy Damien M. , McDyre Lucia E. , Carter Emma , Stasch Andreas , Jones Cameron 
Published: January 2011

AbstractIn this paper, the paramagnetic properties of a novel magnesium ketyl radical (compound 1), formed by reduction of benzophenone with a dimeric Mg(I) complex in the presence of dimethylaminopyridine, are described. Using CW EPR, ENDOR and special TRIPLE resonance, the spin distribution in the radical has been explored at variable temperatures (200–298 K). At 298 K, most of the unpaired spin is found to be confined to the (OCPh2•) fragment based on the hyperfine couplings (hfc's) of o‐H = 8.30, m‐H = 3.00 and p‐H = 9.95 MHz. Smaller hfc's to 25 Mg (5.54 MHz) and 14NDMAP (0.90 MHz) were also evidenced in the 298 K EPR spectrum, indicating some spin delocalisation onto the Mg(Nacnac)(DMAP) fragment. At lower temperatures, restricted rotations of the diphenyl rings create an inequivalent spin distribution in the two rings, with o1‐H = 8.80, o2‐H = 7.85, m‐H = 3.00 and p‐H = 10.00 MHz. Copyright © 2011 John Wiley & Sons, Ltd.
Maternal role attainment with medically fragile infants: Part 1. measurement and correlates during the first year of life
Authors: Miles Margaret Shandor , Holditch‐Davis Diane , Burchinal Margaret R. , Brunssen Susan 
Published: January 2011

AbstractThe purpose of this study was to extend scholarship on maternal role attainment (MRA). We used a triangulation of behavioral and self‐report variables to measure MRA—identity, presence, and competence—with mothers of medically fragile infants (n = 81), and explored characteristics that influenced MRA longitudinally. Competence and presence were best measured using both self‐report and observational methods, whereas identity was best measured with a questionnaire. Mothers with less worry reported higher levels of identity. Presence was higher with less alert infants, whereas competence was higher with more alert infants, lower parental role stress, higher education, and being married. Mothers with more illness‐related distress and less alert infants, and unmarried and less educated mothers may need interventions to enhance MRA. © 2011 Wiley Periodicals, Inc. Res Nurs Health 34:20–34, 2011
Western Australian children with acute lymphoblastic leukemia are taller at diagnosis than unaffected children of the same age and sex
Authors: Davis Esther , Jacoby Peter , de Klerk Nicholas H. , Cole Catherine , Milne Elizabeth 
Published: January 2011

AbstractBackgroundAcute lymphoblastic leukemia (ALL) is the commonest childhood malignancy in Australian children. Recently published data from Western Australia suggest a link between proportion of optimal birth weight and the risk of ALL, but few studies have investigated the relationship between growth during infancy and early childhood and risk of leukemia. The aim of this study was to determine whether children diagnosed with ALL in Western Australia were taller at the time of diagnosis than children of the same age and sex in the general population.MethodsRecords of children diagnosed with ALL between January 1984 and June 2008 were accessed. Height before the commencement of chemotherapy was recorded and compared to the height of population norms derived from the Longitudinal Study of Australian Children.ResultsOn average, male cases were 0.67 cm (95% CI −0.21, 1.54 cm) taller and female cases were 0.30 cm (95% CI −0.68, 1.28 cm) taller than population controls.ConclusionsOur results suggest that children diagnosed with ALL in Western Australia are slightly taller than their counterparts in the general population. These findings are consistent with at least one previous study. While this increase in height may be too small to be recognizable clinically, it is consistent with the notion that growth factors play a role in the pathogenesis of ALL beyond infancy. Pediatr Blood Cancer 2011;56:767–770. © 2011 Wiley‐Liss, Inc.
Photoactive liquid crystalline polymers: A comprehensive study of linear and hyperbranched polymers synthesized by A2B2, A2B3, A3B2, and A3B3 approaches
Authors: Rao V. Srinivasa , Samui A. B. 
Published: January 2011

AbstractA series of linear and hyperbranched polyester epoxies, with varied structural parameters such as kinked structure and different dendritic architectures, were synthesized by A2 + B2, A2 + B3, A3 + B2, and A3 + B3 approaches. The structures of synthesized monomers and polymers were confirmed by Fourier transform infrared, 1H NMR, and 13C NMR spectroscopic techniques. The effect of varied structural parameters on phase behavior and photoresponsive properties was investigated by using differential scanning calorimeter, thermal optical polarized microscope, UV–visible spectroscopy, photoviscosity, and refractive index studies. The transition temperatures of hyperbranched polymers were higher than that of the corresponding linear analogues. All the polymers showed nematic phase (nematic droplets) over a broad temperature range. The effect of kinked structural unit on photoresponsive property is less in both linear and hyperbranched architectures. Although the effect of architectural nature is highly considerable within the hyperbranched architectures, the polymer (HPE–33) synthesized by A3 + B3 approach showed highest rate of photocrosslinking, followed by HPE–I 32; HPE–T 32, and HPE–23, which were synthesized by A3 + B2 and A2 + B3 approaches, respectively. The findings in photoresponsive properties were further supported by molecular modeling studies. Substantial variation of refractive index (0.015–0.024) indicates that these polymers could be used for optical recording. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Impact of chorioamnionitis on exhaled nitric oxide and endotracheal aspirate levels of nitrites–nitrates and interleukin‐8 in mechanically ventilated preterm neonates
Authors: Figueras‐Aloy Josep , Salvia‐Roiges Maria Dolors , Rodriguez‐Miguélez J. Manuel , Miracle‐Echegoyen Xavier , Botet‐Mussons Francesc , Marín‐Soria J. Luís , Carbonell‐Estrany Xavier 
Published: January 2011

AbstractObjectivesTo assess the influence of maternal chorioamnionitis on early exhaled nitric oxide (NO) and levels of nitrites–nitrates and interleukin (IL)‐8 in endotracheal aspirate fluid in mechanically ventilated preterm neonates.Study DesignCross‐sectional study.Patient–Subject SelectionBetween September 2007 and August 2009, 54 mechanically ventilated preterm neonates were included. Patients were divided into two groups according to the presence or absence of maternal chorioamnionitis, and those without chorioamnionitis (controls) were further stratified into two subgroups by birth weight < or ≥2,000 g.MethodologyThe ventilator used was a Babylog 8000. The NO level assessed was the plateau value given by the software of the Sievers NOA apparatus. Collection of endotracheal aspirate fluid samples was performed coinciding with routine aspirations and using the dry technique.ResultsThe two groups of control neonates showed statistically significant differences in exhaled NO expressed as nl/min and normalized exhaled NO expressed as either nl/min or nl/min/kg, so they are not homogeneous and cannot be used in clinical practice. Serum C‐reactive protein and endotracheal aspirate levels of nitrites–nitrates were significantly higher in the chorioamnionitis group than in controls (3.6 vs. 1.07 µmol/L; P = 0.035). Nitrites–nitrates levels were positively correlated with exhaled NO in ppb (ρ = 0.367; P = 0.006). Minute exhaled endogenous NO was significantly higher in the chorioamnionitis group (0.48 vs. 0.27 nl/min/kg; P = 0.021).ConclusionsIn mechanically ventilated preterm infants weighing <2,000 g, maternal chorioamnionitis was associated with an increase of early exhaled NO (nl/min/kg) and serum levels of C‐reactive protein and levels of nitrites–nitrates in endotracheal aspirate fluid. Pediatr. Pulmonol. 2011; 46:595–603. © 2011 Wiley‐Liss, Inc.
Structural changes of Listeria monocytogenes sortase A: A key to understanding the catalytic mechanism
Authors: Tian Boxue , Eriksson Leif A. 
Published: January 2011

AbstractListeria monocytogenes is one of the most virulent foodborne pathogens. L. monocytogenes Sortase A (SrtA) enzyme, which catalyzes the cell wall anchoring reaction of the leucine, proline, X, threonine, and glycine proteins (LPXTG, where X is any amino acid), is a target for the development of antilisteriosis drugs. In this study, the structure of the L. monocytogenes SrtA enzyme‐substrate complex was obtained using homology modeling, molecular docking and molecular dynamics simulations. Explicit enzyme‐substrate interactions in the inactive and active forms of the enzyme were compared, based on 30ns simulations on each system. The active site arginine (Arg 197) was found to be able change its hydrogen donor interactions from the LP backbone carbonyl groups of the LPXTG substrate in the inactive form, to the TG backbone carbonyls in the active form, which could be of importance for holding the substrate in position for the catalytic process. Proteins 2011; © 2011 Wiley‐Liss, Inc.
Computation of ionization and various excited state energies ofhelium and helium‐like quantum dots
Authors: Yakar Yusuf , Çakir Bekir , Özmen Ayhan 
Published: January 2011

AbstractIn the effective mass approximation, we calculated the wave functions and some energy states of helium and helium‐like quantum dots (QDs) with impurity charges Z = 0, 1, 2, 3, and 4. In addition, we carried out the ionization energies of these QDs as a function of dot radius, and we investigated the influence of impurity on the ionization energy. We utilized the method that is a combination of quantum genetic algorithm (QGA) and Hartree‐Fock Roothaan (HFR). The results are in a good agreement with literature results. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Influence of the active space on CASSCF nonadiabatic dynamics simulations
Authors: Szymczak Jaroslaw J. , Barbatti Mario , Lischka Hans 
Published: January 2011

AbstractNonadiabatic dynamics simulations are performed at four different extended ab initio CASSCF levels for 4‐aminopyrimidine, which had been selected because of its structural relationship to DNA nucleobases, aiming at the assessment of the influence of the active space composition on the qualitative and quantitative dynamics predictions. Reaction pathways connecting the Franck‐Condon region to the three main regions of the conical intersection seam were also computed at the same four levels and also using the CASPT2 method. The results show that the theoretical approach has significant influence on quantitative aspects of the dynamics. Nevertheless, relatively uniform qualitative predictions are obtained independently of the CAS level. A well‐balanced treatment of lone‐pair orbitals in the active space was shown to be a key factor for the reliability of the results. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem 111:3307–3315, 2011
An Ab initio theoretical investigation on the geometrical and electronic structures of BAun−/0 (n = 1–4) clusters
Authors: Li Da‐Zhi , Li Si‐Dian 
Published: January 2011

AbstractAn ab initio theoretical investigation on the geometrical and electronic structures and photoelectron spectroscopies (PES) of BAun−/0 (n = 1–4) auroboranes has been performed in this work. Density functional theory and coupled cluster method (CCSD(T)) calculations indicate that BAu (n = 1–4) clusters with n‐Au terminals possess similar geometrical structures and bonding patterns with the corresponding boron hydrides BH. The PES spectra of BAu (n = 1–4) anions have been simulated computationally to facilitate their future experimental characterizations. In this series, the Td BAu anion appears to be unique and particularly interesting: it possesses a perfect tetrahedral geometry and has the highest vertical electron detachment energy (VDE = 3.69 eV), largest HOMO‐LUMO gap (ΔEgap = 3.0 eV), and the highest first excitation energy (Eex = 2.18 eV). The possibility to use the tetrahedral BAu unit as the building block of Li+[BAu4]− ion‐pair and other [BAu4]−‐containing inorganic solids is discussed. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Characterization and selectivity studies of molecular imprinted membranes of Puerarin using scanning electron microscopy
Authors: Qin Peiyong , Yang Jie , Karim M. Nazmul 
Published: January 2011

AbstractMolecular‐imprinted membranes of Puerarin were prepared by phase inversion technique with acrylonitrile–acrylic acid copolymer (P (AN‐co‐AA)). To characterize P (AN‐co‐AA), ubbelohde viscometer was used to measure its viscosity–molecular weight. P (AN‐co‐AA) with different molecular weight was used to prepare membranes. The copolymer–dimethyl sulfoxide solution with Puerarin (PU) template was coagulated in water at various temperatures. The increase in P (AN‐co‐AA) molecular weight and the decrease in coagulation temperature caused an increase in PU recognition property of the resultant membrane. The PU imprinted membrane prepared with P (AN‐co‐AA) showed good selective ability to PU. The purity of PU increased from 56.51 to 98.41 wt%. Surface and cross‐section morphology of the membranes were analyzed by using scanning electron micrograph. High‐performance liquid chromatography was used for the quantification of Puerarin in isolated fraction. SCANNING 33: 7–12, 2011. © 2011 Wiley Periodicals, Inc.
A dynamic model of counterinsurgency policy including the effects of intelligence, public security, popular support, and insurgent experience
Authors: Anderson Edward G. 
Published: January 2011

AbstractA system dynamics model of insurgencies is built using the U.S. Army and Marine Counterinsurgency Manual (FM 3‐24) as a basis. It must, however, be supplemented by additional theory from outside sources to enable calibration to a historical dataset. Parameter and policy analyses are conducted. These highlight the criticality of some features of insurgencies described by FM 3‐24 such as the importance of obtaining and maintaining popular support and employing sufficient counterinsurgency forces to gather intelligence. Other features, not highlighted by FM 3‐24, are also shown to be important such as the rate at which the number of violent incidents committed per insurgent increases during the insurgency and how easily detained/eliminated insurgents can be replaced. A number of sensitivity and policy tests are conducted. One finding, which supports conventional wisdom, is that the timing of withdrawal of counterinsurgency forces is critical. In particular, if the withdrawal is too early, the insurgency may end up being worse than if no counterinsurgency forces had ever been deployed. A second result is support for the contention that counterinsurgency policies are synergistic, which implies that policies are most effective if deployed together. Finally, contraindicating the expectations of FM 3‐24 and other conventional wisdom, results from optimization simulations suggest that counterinsurgency forces should in many cases initially emphasize intelligence‐gathering efforts and minimize direct combat action against the insurgents. Only later in the counterinsurgency effort should counterinsurgency forces reverse this policy and ramp up direct combat action against the insurgents. Copyright © 2011 System Dynamics Society.
Time‐dependent ROC analysis under diverse censoring patterns
Authors: Li Jialiang , Ma Shuangge 
Published: January 2011

AbstractIn biomedical studies, statistical approaches based on the Receiver Operating Characteristic (ROC) analysis have been extensively used in the evaluation of classification performance of markers and construction of classifiers. In this article, we investigate time‐dependent ROC approaches for censored survival data. While most existing studies have been focused on uncensored and right‐censored data, insufficient attention has been paid to other censoring schemes. This study advances from existing studies by investigating more diverse censoring schemes and developing ROC measurements under such censoring. Both estimation and inference are investigated. We conduct simulation and find satisfactory performance of the proposed approaches. We apply the proposed approaches to two real data sets, compare the prognostic power of markers, and investigate whether their linear combinations have better prognostic performance. We also explore graphical tools that can assist diagnostics and efficiently monitor the classification performance. Copyright © 2011 John Wiley & Sons, Ltd.
Multiwalled Carbon‐Nanotube‐Functionalized Microelectrode Arrays Fabricated by Microcontact Printing: Platform for Studying Chemical and Electrical Neuronal Signaling
Authors: Fuchsberger Kai , Goff Alan Le , Gambazzi Luca , Toma Francesca Maria , Goldoni Andrea , Giugliano Michele , Stelzle Martin , Prato Maurizio 
Published: January 2011

AbstractA facile method is proposed for the deposition of multiwalled carbon nanotube (MWCNT) layers onto microelectrode arrays by means of a microcontact printing technique, leading to the fabrication of MEAs characterized by well defined electrical and morphological properties. Using polydimethyl siloxane stamps, produced from different mold designs, a flexibility of printing is achieved that provides access to microscale, nanostructured electrodes. The thickness of MWCNT layers can be exactly predetermined by evaluating the concentration of the MWCNT solution employed in the process. The electrode morphology is further characterized using laser scanning and scanning electron microscopy. Next, by means of impedance spectroscopy analysis, the MWCNT–electrode contact resistance and MWCNT film resistance is measured, while electrochemical impedance spectroscopy is used to estimate the obtained electrode–electrolyte interface. Structural and electrochemical properties make these electrodes suitable for electrical stimulation and recording of neurons and electrochemical detection of dopamine. MWCNT‐functionalized electrodes show the ability to detect micromolar amounts of dopamine with a sensitivity of 19 nA μm−1. In combination with their biosensing properties, preliminary electrophysiological measurements show that MWCNT microelectrodes have recording properties superior to those of commercial TiN microelectrodes when detecting neuronal electrical activity under long‐term cell‐culture conditions. MWCNT‐functionalized microelectrode arrays fabricated by microcontact printing represent a versatile and multipurpose platform for cell‐culture monitoring.
Handover of relay stations for load balancing in IEEE 802.16
Authors: Mach Pavel , Becvar Zdenek , Bestak Robert 
Published: January 2011

ABSTRACTThe load balancing in wireless networks is a very effective way for maximization of a system throughput. The paper proposes a new load balancing scheme in order to avoid a congestion of base stations (BSs) in IEEE 802.16 standards. While in many technical studies the load balancing is achieved by a handover (HO) of mobile stations (MSs), the novelty of our approach lies in the utilization of the HO of relay stations (RSs). Hence, the algorithm enabling load balancingviaRSs is developed and optimized. Furthermore, the paper contemplates the implementation of the proposed mechanism to networks based on IEEE 802.16 standards. The performance of the mechanism is evaluated in terms of achieved system throughput and signaling overhead both at the air interface and over the wired backbone. The obtained results indicate that the load balancing mechanism through the HO of RSs outperforms existing load balancing mechanisms exploiting conventional HO of MSs. Copyright © 2011 John Wiley & Sons, Ltd.