bluuebunny/crossref_metadata_2025_split huggingface dataset:
FMR investigations of half‐metallic ferromagnets
Authors: Rameev B. , Yildiz F. , Kazan S. , Aktas B. , Gupta A. , Tagirov L. R. , Rata D. , Buergler D. , Gruenberg P. , Schneider C. M. , Kämmerer S. , Reiss G. , Hütten A. 
Published: April 2006

AbstractThin films of various half‐metallic ferromagnets, such as chromium dioxide (CrO2) and Heusler alloys (Co2Cr0.6Fe0.4Al, Co2MnSi) have been investigated by ferromagnetic resonance (FMR) technique. It is demonstrated that FMR is a very efficient method to study the nanoscale magnetic properties, in particular to probe the magnetic anisotropy and magnetic inhomogeneities of ferromagnetic thin films. Epitaxial CrO2 thin films of various thicknesses (25–535 nm) have been deposited on TiO2(100) substrates by chemical vapor deposition process. It is shown that the magnetic behavior of the CrO2 films results from a competition between the magnetocrystalline and strain anisotropies. For the ultrathin CrO2 film (25 nm) the magnetic easy axis switches from the c‐direction to the b‐direction of the rutile structure. Thin‐film Co2Cr0.6Fe0.4Al samples (25 nm or 100 nm) have been grown by DC magnetron sputtering either on unbuffered SiO2(100) substrates or on the substrates capped by a 50 nm thick V buffer layer. The effects of the vanadium buffer layer and of the film thickness are revealed by FMR studies of the Co2Cr0.6Fe0.4Al samples. Well‐resolved multiple spin‐wave modes are observed in the unbuffered Co2Cr0.6Fe0.4Al sample with a thickness of 100 nm and the exchange stiffness constant has been estimated. Thin films of Co2MnSi (4–100 nm) have been grown by DC sputtering on silicon substrates on top of a 42 nm thick V seed layer and capped either by Al2O3 or by Co and V layers. A set of the 80 nm thick films has been annealed at different temperatures in the range of 425–550 °C. FMR studies of the Co2MnSi samples shows that at the fixed annealing temperature (450 °C) the highest magnetization is observed in the sample with a thickness of 61 nm, while the thicker samples (100 nm) reveal not only a lower magnetization but greater magnetic inhomogeneity as well. An annealing treatment at T ≥ 450 °C is essential to obtain higher magnetization as well as uniform magnetic properties in the Co2MnSi films. Weak SWR modes have also been observed in the thick Heusler films. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Differentiation of estriol glucuronide isomers by chemical derivatization and electrospray tandem mass spectrometry
Authors: Lampinen‐Salomonsson Matilda , Bondesson Ulf , Petersson Carl , Hedeland Mikael 
Published: April 2006

AbstractThis paper describes a way of differentiating between the three isomers of estriol glucuronide by the use of chemical derivatization and liquid chromatography/electrospray tandem mass spectrometry (MS/MS). In their native form, these isomers gave rise to almost identical product ion spectra, involving the neutral loss of 176 Da (i.e. monodehydrated glucuronic acid), which made it impossible to determine the position of conjugation by MS/MS alone. In order to change the fragmentation pathways, positive charges were introduced into the analytes by chemical derivatization. The following reagents were tested: 2‐chloro‐1‐methylpyridinium iodide, 1‐ethyl‐3‐(3‐dimethylaminopropyl)carbodiimide and 2‐picolylamine. Interestingly, derivatization using a combination of all three reagents gave a selective fragmentation pattern that could differentiate between the isomers estriol‐16‐glucuronide and estriol‐17‐glucuronide. Estriol‐3‐glucuronide, which lacks a free phenolic group, could be differentiated through a different type of reaction product when exposed to 2‐chloro‐1‐methylpyridinium iodide. Furthermore, in order to assist structural assignment of the fragments, their accurate masses were determined using a hybrid quadrupole time‐of‐flight mass spectrometer and fragmentation pathways were elucidated by the use of MS3 on an ion trap mass spectrometer. Copyright © 2006 John Wiley & Sons, Ltd.
Characterization of a mini membrane inlet mass spectrometer for on‐site detection of contaminants in both aqueous and liquid organic samples
Authors: Janfelt Christian , Frandsen Helle , Lauritsen Frants R. 
Published: April 2006

AbstractA mini membrane inlet mass spectrometer (mini‐MIMS) of a total weight of 12 kg was constructed using a miniature Multipole mass spectrometer, a small vacuum system and a flexible flat sheet membrane inlet, where the exposed membrane area can be changed by a factor of 80. The variable membrane area together with the possibility of operating the Multipole at pressures up to 1 × 10−3 Torr made it possible to test the system with three microporous membranes (cellulose, polyether sulfone and polypropylene) normally not compatible with standard electron ionization MIMS systems and a standard non‐porous polydimethylsiloxane membrane. We found that the hydrophilic cellulose and polyether sulfone membranes had selectivity characteristics opposite to those of the standard silicone membrane. They demonstrated preferential detection of hydrophilic compounds in hydrophobic organic solvents, whereas the silicone membrane preferentially detects hydrophobic organic compounds in aqueous solution. Using the cellulose membrane, organic contaminants and water could be detected in organic solvents at 10–100 ppm levels by weight, the relative high detection limits primarily caused by interference from a high chemical background from the solvent. When being used with the standard silicone membrane the mini‐MIMS behaved just like most standard MIMS systems with detection limits of volatile organic compounds in water at concentrations just below 1 ppm. The hydrophobic microporous polypropylene membrane was not found to be useful with the mini‐MIMS. Copyright © 2006 John Wiley & Sons, Ltd.
A high‐performance liquid chromatography/tandem mass spectrometry method for the determination of artemisinin in rat plasma
Authors: Xing Jie , Yan Hongxia , Zhang Shuqiu , Ren Guolian , Gao Yanhui 
Published: April 2006

AbstractArtemisinin is a widely used antimalarial drug. To evaluate the pharmacokinetics of artemisinin in rats, a sensitive and specific liquid chromatography/tandem mass spectrometric (LC/MS/MS) method was developed and validated for the determination of artemisinin in rat plasma. For detection, a Sciex API 4000 LC/MS/MS instrument with an electrospray ionization (ESI) TurboIonSpray inlet in the positive ion multiple reaction monitoring (MRM) mode was used to monitor precursor ([M+NH4]+) → product ions of m/z 300.4 → 209.4 for artemisinin and m/z 316.4 → 163.4 for artemether, the internal standard (IS). The plasma samples were pretreated by a simple liquid‐liquid extraction with ether. The standard curve was linear (r > 0.99) over the artemisinin concentration range of 1.0–200.0 ng/mL in plasma. The method had a lower limit of quantification of 1.0 ng/mL for artemisinin in 100 µL of plasma, which offered a satisfactory sensitivity for the determination of artemisinin. The intra‐ and inter‐day precisions were measured to be within ±5.3% and accuracy between −2.6% and 1.2% for all quality control samples, lower limit of quantification and upper limit of quantification samples. The extraction recoveries of artemisinin and the IS were 95.4 ± 4.5% and 92.8 ± 3.9%, respectively. This present method was successfully applied to the characterization of the pharmacokinetic profile of artemisinin in rats after oral administration. Copyright © 2006 John Wiley & Sons, Ltd.
Metabolism of a new P‐glycoprotein inhibitor HM‐30181 in rats using liquid chromatography/electrospray mass spectrometry
Authors: Paek In Bok , Ji Hye Young , Kim Maeng Sup , Lee Gwansun , Lee Hye Suk 
Published: April 2006

AbstractHM‐30181, 4‐oxo‐4H‐chromene‐2‐carboxylic acid, [2‐(2‐{4‐[2‐(6,7‐dimethoxy‐3,4‐dihydro‐1H‐isoquinolin‐2‐yl)‐ethyl]‐phenyl}‐2H‐tetrazol‐5‐yl)‐4,5‐dimethoxyphenyl]amide, is a new P‐glycoprotein inhibitor. This study was performed to identify the in vitro and in vivo metabolic pathway of HM‐30181 in rats. Rat liver microsomal incubation of HM‐30181 in the presence of NADPH resulted in the formation of four metabolites, M1–M4. M1 and M2 were identified as 2‐(2‐{4‐[2‐(6,7‐dimethoxy‐3,4‐dihydro‐1H‐isoquinolin‐2‐yl)‐ethyl]‐phenyl}‐2H‐tetrazol‐5‐yl)‐4,5‐dimethoxyaniline and 4‐ or 5‐O‐desmethyl‐HM‐30181, respectively, on the basis of liquid chromatography/tandem mass spectrometry (LC/MS/MS) analysis with the synthesized authentic standards. M3 and M4 were suggested to be 6‐ or 7‐O‐desmethyl‐HM‐30181 and hydroxy‐HM‐30181, respectively. These in vitro metabolites were also detected in feces and urine samples after an intravenous administration of HM‐30181 to male rats. The metabolic routes for HM‐30181 were O‐demethylation of the methoxy group to M2 and M3, hydrolysis of the amide group to M1, and hydroxylation to M4. Copyright © 2006 John Wiley & Sons, Ltd.
The use of recently described ionisation techniques for the rapid analysis of some common drugs and samples of biological origin
Authors: Williams Jonathan P. , Patel Vibhuti J. , Holland Richard , Scrivens James H. 
Published: April 2006

AbstractThree ionisation techniques that require no sample preparation or extraction prior to mass analysis have been used for the rapid analysis of pharmaceutical tablets and ointments. These methods were (i) the novel direct analysis in real time (DART), (ii) desorption electrospray ionisation (DESI), and (iii) desorption atmospheric pressure chemical ionisation (DAPCI). The performance of the three techniques was investigated for a number of common drugs. Significant differences between these approaches were observed. For compounds of moderate to low polarity DAPCI produced more effective ionisation. Accurate DESI and DAPCI tandem mass spectra were obtained and these greatly enhance the selectivity and information content of the experiment. The detection from human skin of the active ingredients from ointments is reported together with the detection of ibuprofen metabolites in human urine. Copyright © 2006 John Wiley & Sons, Ltd.
Structural assignment of isomeric 2‐aminopyridine‐derivatized monosialylated biantennary N‐linked oligosaccharides using negative‐ion multistage tandem mass spectral matching
Authors: Deguchi Kisaburo , Takegawa Yasuhiro , Ito Hiroki , Miura Nobuaki , Yoshioka Shinji , Nagai Shinji , Nakagawa Hiroaki , Nishimura Shin‐Ichiro 
Published: April 2006

AbstractThe original article to which this Erratum refers was published in Rapid Commun. Mass Spectrom. 2006; 20: 412–418
Robotic mitral surgery at East Carolina University: a 6 year experience
Authors: Rodríguez Evelio , Kypson Alan P. , Moten Simon C. , Nifong L. Wiley , Chitwood W. Randolph 
Published: April 2006

AbstractBackgroundRobotic mitral valve repair using the da Vinci™ telemanupilation system has become the standard of care at many centres worldwide. We perform the first robotic MV repair in the United States in the year 2000. This article reviews our 6 year experience and current technique of robotic MV repair as well as future trends in the field.MethodsRetrospective review of our initial 200 robotic MV repairs. Patient demographics, operative times, type of repairs, morbidities, mortality, success of the repair including need for reoperations were reviewed.ResultsThe average age was 57 ± 0.9 years. Average time for CPB was 156 minutes and for cross clamp 119 minutes. There was one operative death (0.5%) with no device related complications. Postoperative TEE demonstrated no MR in 187 (93.5%) patients, trace MR in 6 (3%) patients, moderate MR in 5 (2.5%) patients, and SAM in 2 (1%) patients. Five (2.5%) patients required reoperation for failed repairs.ConclusionsRobotic MV repair operations are safe with excellent early results. Follow‐up studies are needed to determine repair longevity. We must continue to improve the current technology in order to develop the next generation of tools that will facilitate robotic MV repairs. Copyright © 2006 John Wiley & Sons, Ltd.
A surgical telemanipulator for femur shaft fracture reduction
Authors: Westphal R. , Winkelbach S. , Gösling T. , Hüfner T. , Faulstich J. , Martin P. , Krettek C. , Wahl F. M. 
Published: April 2006

AbstractBackgroundWe present a surgical telemanipulator system supporting long bone fracture reduction procedures. This paper gives an overview of the robotic system developed by our working group and describes a possible workflow for telemanipulated fracture reduction. The concepts enabling an intuitive control of the robot using a joystick with force feedback as input device are also described.MethodsWith our robotic set‐up we performed a test series, in order to evaluate the achievable reposition accuracies and operation times. 11 femoral shaft fractures in seven human donors have been reduced with the telemanipulator and the results have been compared with those achieved by conventional manual and navigated manual repositions.ResultsAll fractures in our test series could be reduced successfully with the telemanipulator, achieving a mean rotational deviation of 4.9° in axial direction and 2.5° and 3.5° in AP and lateral direction. We could find no statistically significant difference between the accuracies achieved by the telemanipulator and those achieved by the two manual procedures. The image intensifier usage times of our telemanipulated repositions were conspicuously lower compared to the conventional manual repositions and statistically significant lower compared to the navigated repositions.ConclusionWe could show that robot‐assisted fracture reduction is possible, yielding good accuracies and a conspicuous reduction of X‐ray irradiation. However, we also show the limitations regarding reposition accuracies of telemanipulated fracture reduction when it is based on 2D X‐ray imaging only. From the combination of 3D imaging, automated computation of the reduction parameters, and automated force/torque guided reduction by the robot we expect to overcome these limitations in our future work. Copyright © 2006 John Wiley & Sons, Ltd.
Genome‐wide identification of genes required for growth of Saccharomyces cerevisiae under ethanol stress
Authors: van Voorst Frank , Houghton‐Larsen Jens , Jønson Lars , Kielland‐Brandt Morten C. , Brandt Anders 
Published: April 2006

AbstractThe Saccharomyces cerevisiae deletion collection was screened for impaired growth on glucose‐based complex medium containing 6% ethanol. Forty‐six mutants were found. Genes encoding proteins involved in vacuolar function, the cell integrity pathway, mitochondrial function, subunits of the co‐chaperone complex GimC and components of the SAGA transcription factor complex were in this way found to be important for the growth of wild‐type Saccharomyces yeast in the presence of ethanol. Several mutants were also sensitive to Calcofluor white (14 mutants), sorbic acid (9), increased temperature (5) and NaCl (3). The transcription factors Msn2p and Ars1p, tagged with green fluorescent protein, were translocated to the nucleus upon ethanol stress. Only one of the genes that contain STRE elements in the promoter was important under ethanol stress; this was TPS1, encoding trehalose 6‐phosphate synthase. The map kinase of the cell integrity pathway, Slt2p, was phosphorylated when cells were treated with 6% ethanol. Two out of three mutants tested fermented 20% glucose more slowly than the wild‐type. Copyright © 2006 John Wiley & Sons, Ltd.
Evaluation of relative density indices for sika deer in eastern Hokkaido, Japan
Authors: Uno Hiroyuki , Kaji Koichi , Saitoh Takashi , Matsuda Hiroyuki , Hirakawa Hirofumi , Yamamura Kohji , Tamada Katsumi 
Published: April 2006

AbstractWe evaluated relative density indices of sika deer (Cervus nippon) to aid in population management. We monitored sika deer population trends from 1992 to 2002 in the eastern part of Hokkaido Island, northern Japan, using spotlight surveys, aerial surveys, catch per unit effort (CPUE), sighting per unit effort (SPUE), and cost of damage to agriculture and forestry. We assumed that the artificial bias in the spotlight index would be lower than in other indices, and compared temporal patterns of other indices to those produced using spotlight surveys using model II regression. There was a significant correlation between the damage cost index and the spotlight index, and both indices indicated consistent population trends. Managers used CPUE as a tool to determine hunting quota efficiency. The SPUE index had the smallest standard error among the indices, and the spotlight survey index had the second smallest standard error. Overall, the spotlight survey was the most useful index because its estimate error was small and it was precise in showing population trends; however, spotlight surveys did lead to underestimation once in 1994. The SPUE index seems to be effective in checking the validity of the spotlight index, but there are so many environmental and demographic uncertainties that several independent indices should be used and crosschecked for accurate evaluation of population trends.
Coupled ecological and social dynamics in a forested landscape: the deviation of individual decisions from the social optimum
Authors: Satake Akiko , Iwasa Yoh 
Published: April 2006

AbstractWe present a Markov chain model for land‐use dynamics in a forested landscape. This model emphasizes the importance of coupling socioeconomic and ecological processes underlying landscape change. We assume that a forest is composed of many land parcels, each of which is in one of a finite list of land‐use states. The land‐use state of each land parcel changes stochastically. The transition probability is determined by two processes: the forest succession and the decision of landowners. The landowner tends to choose the land‐use state which has a high expected discounted utility, i.e., the sum of the current and the future utilities of the land parcel. Landowners take the likelihood of future landscape changes into account when making decisions. We focus on a three‐state model in which forested, agricultural, and abandoned states are considered. The land‐use composition at equilibrium was analyzed and compared with the social optimum that maximizes the net benefit of all landowners in a society. We show that when landowners make a myopic choice focused on short‐term benefits, their individual decisions tend to push the entire landscape toward an agricultural state even if the forested state represents the highest utility. This land‐use composition at equilibrium is very different from the social optimum. A long‐term management perspective and an enhanced rate of forest recovery can eliminate the discrepancy.
Gender differences in the self‐defining activities and identity experiences of adolescents and emerging adults
Authors: Sharp Erin Hiley , Coatsworth J. Douglas , Darling Nancy , Cumsille Patricio , Ranieri Sonia 
Published: April 2006

AbstractActivity participation provides a unique context for adolescents and emerging adults to explore interests, talents, and skills and for identity work to occur. Research has found consistent gender differences in the types of activities in which males and females participate. The current study drew on Eudaimonistic identity theory to examine the subjective identity‐related experiences of personal expressiveness, flow experiences, and goal‐directed behaviour [Waterman, 1984; Waterman, 2004. Finding someone to be: Studies on the role of intrinsic motivation in identity formation. Identity, 4, 209–228] within a special type of activity, self‐defining activities, or those activities that participants identify as being important to who they are as a person. This study also tested for gender and country differences in a sample of 572 adolescents and emerging adults from the United States, Italy, and Chile. Findings indicate gender and country differences in the types of self‐defining activities for males and females, but no gender differences in the reported identity‐related experiences within those activities. This finding held across the three countries. Results from Multivariate Analyses of Variance also indicate that identity‐related experiences differ significantly across seven broad activity classes. Findings are discussed in the context of the growing literature on adolescent activity involvement and time use, gender, and their relations to identity exploration.
How is impulsivity related to depression in adolescence? Evidence from a French validation of the cognitive emotion regulation questionnaire
Authors: d’Acremont Mathieu , Van der Linden Martial 
Published: April 2006

AbstractThe aim of this study was to validate a French version of the Cognitive Emotion Regulation Questionnaire (CERQ; Garnefski, N., Kraaij, V., & Spinhoven, P., 2001. Negative life events, cognitive emotion regulation and emotional problems.Personality and Individual Differences,30, 1311–1327) and to explore its relationships with impulsivity and depression. Teenagers from a junior secondary (, 13–16 years) and a secondary school (, 15–19 years) completed the CERQ, which assesses regulation strategies in response to negative events. The secondary school adolescents also completed the UPPS Impulsive Behavior Scale (Whiteside, S. P., & Lynam, D. R., 2001. The five factor model and impulsivity: Using a structural model of personality to understand impulsivity.Personality and Individual Differences,30, 669–689) and the Reynolds Adolescent Depression Scale (Reynolds, W. M., 1987.Reynolds Adolescent Depression Scale: Professional manual. Odessa, FL: Psychological Assessment Resources). Factor analysis for the CERQ confirmed the presence of the nine original regulation strategies. In the secondary school students, impulsivity was related to depression. A path analysis revealed that regulation strategies mediated this relationship. The role of emotion regulation in the development of adolescent psychopathology is discussed.
Regulation of ERK1/2 activity by ghrelin‐activated growth hormone secretagogue receptor 1A involves a PLC/PKCɛ pathway
Authors: Mousseaux Delphine , Le Gallic Lionel , Ryan Joanne , Oiry Catherine , Gagne Didier , Fehrentz Jean‐Alain , Galleyrand Jean‐Claude , Martinez Jean 
Published: April 2006

The growth hormone secretagogue receptor 1a (GHSR‐1a) is a G‐protein coupled receptor, involved in the biological actions of ghrelin by triggering inositol phosphates and calcium intracellular second messengers. It has also been reported that ghrelin could activate the 44‐ and 42‐kDa extracellular signal‐regulated protein kinases (ERK1/2) in different cell lines, but it is not clear whether this regulation is GHSR‐1a dependent or not.
To provide direct evidence for the coupling of GHSR‐1a to ERK1/2 activation, this pathway has been studied in a heterologous expression system.
Thus, in Chinese hamster ovary (CHO) cells we showed that ghrelin induced, via the human GHSR‐1a, a transient and dose‐dependent activation of ERK1/2 leading to activation of the transcriptional factor Elk1.
We then investigated the precise mechanisms involved in GHSR‐1a‐mediated ERK1/2 activation using various specific inhibitors and dominant‐negative mutants and found that internalization of GHSR‐1a was not necessary. Our results also indicate that phospholipase C (PLC) was involved in GHSR‐1a‐mediated ERK1/2 activation, however, pathways like tyrosine kinases, including Src, and phosphoinositide 3‐kinases were not found to be involved. GHSR‐1a‐mediated ERK1/2 activation was abolished both by a general protein kinase C (PKC) inhibitor, Gö6983, and by PKC depletion using overnight pretreatment with phorbol ester. Moreover, the calcium chelator, BAPTA‐AM, and the inhibitor of conventional PKCs, Gö6976, had no effect on the GHSR‐1a‐mediated ERK1/2 activation, suggesting the involvement of novel PKC isoforms (ɛ, δ), but not conventional or atypical PKCs. Further analyses suggest that PKCɛ is required for the activation of ERK1/2.
Taken together, these data suggest that ghrelin, through GHSR‐1a, activates the Elk1 transcriptional factor and ERK1/2 by a PLC‐ and PKCɛ‐dependent pathway.

British Journal of Pharmacology (2006) 148, 350–365. doi:10.1038/sj.bjp.0706727