bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reactions of 1,2,4‐Trithiolane, 1,2,5‐Trithiepane, 1,2,5‐Trithiocane and 1,2,6‐Trithionane with Nonacarbonyldiiron: Structural Determination and Electrochemical Investigation
Authors: Windhager Jochen , Rudolph Manfred , Bräutigam Silvio , Görls Helmar , Weigand Wolfgang 
Published: April 2007

AbstractThe reactions of 1,2,4‐trithiolane (1), 1,2,5‐trithiepane (6), 1,2,5‐trithiocane (12) and 1,2,6‐trithionane (10) with nonacarbonyldiiron (2) have been investigated. A novel diiron model complex, which can serve as a model complex of the active site of [Fe‐only]‐hydrogenase, was formed from the reaction with 1. In contrast, the reaction of 6 with 2 afforded the trinuclear iron cluster 7. Interestingly, the diiron compound 11 was obtained with 1,2,6‐trithionane (10), which can be attributed to the more flexible dithiolato ligand 10. Furthermore, the reaction with 1,2,5‐trithiocane (12) yielded the trinuclear cluster 13. X‐ray structure analyses were performed on compounds 3, 7, 10, 11 and 13. The reactions of the reduced iron species 3 with pivalic acid (HP) were studied electrochemically. The most significant features of the experimental cyclic voltammograms (CVs) could be reproduced by digital simulation on the basis of a reaction scheme that includes both the coordination of HP as well as the catalytic generation of hydrogen. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Asymmetric Synthesis of Aliphatic 2‐Hydroxy Ketones by Enzymatic Carboligation of Aldehydes
Authors: Domínguez de María Pablo , Pohl Martina , Gocke Dörte , Gröger Harald , Trauthwein Harald , Stillger Thomas , Walter Lydia , Müller Michael 
Published: April 2007

AbstractBenzaldehyde lyase (BAL) and benzoylformate decarboxylase (BFD) catalyse the asymmetric ligation of aliphatic aldehydes to afford enantiomerically enriched 2‐hydroxy ketones. Carboligation of linear aldehydes with both enzymes results in high levels of conversion and in enantioselectivities of up to 80 % ee. In cases involving branched aliphatic aldehydes, BAL enables the carboligation of 3‐methylbutanal with a high level of conversion and an enantioselectivity of 89 % ee.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Isotope distribution of dissolved carbonate species in southeastern coastal aquifers of Sicily (Italy)
Authors: Schiavo M. A. , Hauser S. , Povinec P. P. 
Published: April 2007

AbstractConcentrations of major ions and the δ13C composition of dissolved inorganic carbon in groundwater and submarine groundwater discharges in the area between Siracusa and Ragusa provinces, southeastern Sicily, representing coastal carbonate aquifers, are presented and discussed. Most of groundwater analysed belongs to calcium bicarbonate type, in agreement with the geological nature of carbonate host rocks. Carbonate groundwater acquires, besides the dissolution of carbonate minerals, dissolved carbon (and the relative isotopic composition) from the atmosphere and from soil biological activity. In fact, δ13C values and total dissolved inorganic carbon contents show that both these sources contribute to carbon dissolved species in the waters studied. Finally, mixing with seawater in the second main factor of groundwater mineralization Copyright © 2007 John Wiley & Sons, Ltd.
God's will, God's punishment, or God's limitations? Religious coping strategies reported by young adults living with serious mental illness
Authors: Phillips Russell E. , Stein Catherine H. 
Published: April 2007

AbstractQualitative research has demonstrated that religious meaning‐making coping, defined as attributions of a stressful life event that involve the sacred, is particularly relevant to persons with serious mental illness. However, recent research advances in the study of religious coping have yet to be employed in clinical samples. This longitudinal study examines religious meaning‐making coping in a sample of 48 young adults diagnosed with schizophrenia or bipolar disorder over a one‐year period. Young adults with mental illness generally reported using religious meaning‐making coping in levels comparable to nonpsychiatric samples. Reports of benevolent religious reappraisals were associated with perceptions of positive mental health, whereas punishing God reappraisals and reappraisals of God's power were associated with self‐reported distress and personal loss. Religious coping variables accounted for variation in adults' reports of psychiatric symptoms and personal loss one year later over and above demographic and global religious variables. Implications of findings for clinical practice are discussed. © 2007 Wiley Periodicals, Inc. J Clin Psychol.
Occult hepatitis B virus infection in the setting of hepatitis C virus (HCV) and human immunodeficiency virus (HIV) co‐infection: Clinically relevant or a diagnostic problem?
Authors: Rodríguez‐Torres M. , Gonzalez‐Garcia J. , Bräu N. , Solá R. , Moreno S. , Rockstroh J. , Smaill F. , Mendes‐Correa M.C. , DePamphilis J. , Torriani F.J. ,   for the APRICOT investigators
Published: April 2007

AbstractThe clinical relevance of occult hepatitis B virus (HBV) infection, defined as detectable HBV DNA serum/liver, in the absence of hepatitis B surface antigen (HBsAg), is unclear. We determined the prevalence of serum occult HBV infection in HIV/HCV co‐infected patients enrolled in APRICOT, a randomized multinational trial that investigated the efficacy and safety of peginterferon alfa‐2a (40 kDa) plus ribavirin for treatment of HCV. We also examined the effect of prior HBV exposure to liver histology at baseline. Only HBsAg‐negative patients were eligible. At screening, serum HBV DNA was assessed by commercial assay (detection limit = 200 copies/mL). Patients were divided into four serological groups: anti‐HBs+/anti‐HBc+; anti‐HBs−/anti‐HBc+; anti‐HBs+/ anti‐HBc−; anti‐HBs−/anti‐HBc−. Baseline liver biopsy grade and stage were compared among groups. Serum HBV DNA was undetectable in all patients, (n = 866). Results of anti‐HBs and anti‐HBc was available for 176 patients: 60 (34.1%) anti‐HBs+/anti‐HBc+; 60 (34.1%) anti‐HBs−/anti‐HBc+; 11 (6.3%) anti‐HBs+/anti‐HBc−; 45 (25.6%) anti‐HBs−/anti‐HBc−. There were no differences among the groups in the histological grade or stage at baseline liver biopsies. Occult HBV infection in serum was not detected in this large immunocompetent cohort. Moreover, prior exposure to HBV did not appear to have any affect on baseline liver histology. J. Med. Virol. 79: 694–700, 2007. © 2007 Wiley‐Liss, Inc.
Enhanced poly(ADP‐ribose) polymerase‐1 activation contributes to recombinant tissue plasminogen activator‐induced aggravation of ischemic brain injury in vivo
Authors: Crome Olaf , Doeppner Thorsten R. , Schwarting Sönke , Müller Barbara , Bähr Mathias , Weise Jens 
Published: April 2007

AbstractRecombinant tissue plasminogen activator (rt‐PA) treatment improves functional outcome after acute ischemic stroke, inducing reperfusion by its thrombolytic activity. Conversely, there is evidence that rt‐PA can mediate neuronal damage after ischemic brain injury in vivo. In addition to other mechanisms, enhancement of N‐methyl‐D‐aspartate (NMDA) receptor signalling has been proposed to underlie rt‐PA‐mediated neurotoxicity. However, the role of poly(ADP‐ribose) polymerase‐1 (PARP‐1) activation, which mediates postischemic excitotoxic cell death, in rt‐PA‐mediated aggravation of ischemic brain injury has not been established and was therefore addressed in this study. After permanent focal cerebral ischemia, intravenous rt‐PA application significantly increased early postischemic PARP‐1 activation within ischemic hemispheres and infarct volumes compared with control mice without affecting cerebral blood flow. Rt‐PA induced increase in PARP‐1 activation, and infarct volumes could be blocked by the PARP inhibitor 3‐aminobenzamide. Moreover, the rt‐PA‐induced increase in PARP‐1 activation was also prevented by the NMDA antagonist MK‐801. In summary, we demonstrate that rt‐PA treatment enhances postischemic PARP‐1 activation, which contributes to rt‐PA induced aggravation of ischemic brain injury in vivo. Furthermore, we provide evidence that NMDA receptor activation is required for rt‐PA‐mediated effects on postischemic PARP‐1 activation. © 2007 Wiley‐Liss, Inc.
Mechanics of oriented electrospun nanofibrous scaffolds for annulus fibrosus tissue engineering
Authors: Nerurkar Nandan L. , Elliott Dawn M. , Mauck Robert L. 
Published: April 2007

AbstractEngineering a functional replacement for the annulus fibrosus (AF) of the intervertebral disc is contingent upon recapitulation of AF structure, composition, and mechanical properties. In this study, we propose a new paradigm for AF tissue engineering that focuses on the reconstitution of anatomic fiber architecture and uses constitutive modeling to evaluate construct function. A modified electrospinning technique was utilized to generate aligned nanofibrous polymer scaffolds for engineering the basic functional unit of the AF, a single lamella. Scaffolds were tested in uniaxial tension at multiple fiber orientations, demonstrating a nonlinear dependence of modulus on fiber angle that mimicked the nonlinearity and anisotropy of native AF. A homogenization model previously applied to native AF successfully described scaffold mechanical response, and parametric studies demonstrated that nonfibrillar matrix, along with fiber connectivity, are key contributors to tensile mechanics for engineered AF. We demonstrated that AF cells orient themselves along the aligned scaffolds and deposit matrix that contributes to construct mechanics under loading conditions relevant to the in vivo environment. The homogenization model was applied to cell‐seeded constructs and provided quantitative measures for the evolution of matrix and interfibrillar interactions. Finally, the model demonstrated that at fiber angles of the AF (28°–44°), engineered material behaved much like native tissue, suggesting that engineered constructs replicate the physiologic behavior of the single AF lamella. Constitutive modeling provides a powerful tool for analysis of engineered AF neo‐tissue and native AF tissue alike, highlighting key mechanical design criteria for functional AF tissue engineering. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:1018–1028, 2007
Measurement of varus–valgus and internal–external rotational knee laxities in vivo—part i: assessment of measurement reliability and bilateral asymmetry
Authors: Shultz Sandra J. , Shimokochi Yohei , Nguyen Anh‐Dung , Schmitz Randy J. , Beynnon Bruce D. , Perrin David H. 
Published: April 2007

AbstractWe examined the capabilities of the Vermont Knee Laxity Device (VKLD) in measuring varus (VR)–valgus (VL) and internal (INT)–external (EXT) rotational laxities by quantifying measurement consistency and absolute measurement error (N = 10). Based on the expected measurement error, we then examined side‐to‐side differences (N = 20). For all measures, the knee was flexed 20°, the thigh securely fixed, and counterweights applied to the thigh and shank to create an initial zero shear and compressive load across the tibiofemoral joint. A 10‐Nm torque was applied to the knee for VL and VR during non‐weight‐bearing, and a 5‐Nm torque was applied for INT and EXT during non‐weight‐bearing and weight‐bearing conditions. Position sensors measured angular displacements (deg). Except for INT during weight bearing, measurement consistency was good to excellent (range, 0.68–0.96), with absolute measurement errors generally less than 2° for VR–VL and 3–4° for INT–EXT. Although side‐to‐side differences were observed, they did not exceed absolute measurement errors. The VKLD yields reliable measures of VR–VL and INT–EXT laxities, with sufficient measurement precision to yield clinically relevant differences. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:981–988, 2007
A comparison of mass removal, thermal injury, and crater morphology of cortical bone ablation using wavelengths 2.79, 2.9, 6.1, and 6.45 µm
Authors: Youn Jong‐In , Sweet Paula , Peavy George M. 
Published: April 2007

AbstractBackground and ObjectivePrevious investigations have reported evidence of wavelength dependence on cortical bone ablation. This study used mid‐infrared laser wavelengths generated by a free electron laser (FEL) and mass removal measurements to further examine the ablation efficiency of a wavelength (2.79 µm) not previously reported and three wavelengths (2.9, 6.1, and 6.45 µm) previously demonstrated by crater morphology alone to be efficient for cortical bone removal.Study Design/Materials and MethodsThe wavelengths examined were provided by an FEL emitting 4 microseconds macropulses consisting of 1–2 picoseconds duration micropulses delivered at 350 picoseconds intervals. The mass removal measurements were conducted by a microbalance, and the collateral thermal injury and crater morphology of cortical bone were examined by light microscopy following standard histologic processing.ResultsThe study demonstrated that the highest mass removal was achieved at λ = 6.1 µm followed by, in order, λ = 2.9, 6.45, and 2.79 µm. The zones of thermal injury and crater morphology created in cortical bone at the selected wavelengths were examined at the radiant exposure of 28.3 J/cm2. Ablation using λ = 6.1 µm provided the largest crater size and the least collateral thermal injury. The greatest amount of collateral thermal injury was produced by λ = 2.79 µm at both the sides and base of the ablation crater.ConclusionsThe mass removal of cortical bone produced by FEL ablation at selected mid‐IR wavelengths was measured as a function of incident radiant exposure. The ablation efficiency was found to be dependent upon wavelength. The λ = 2.79 µm did not offer any improvement over the other wavelengths evaluated, suggesting that a potential shift in the dynamic optical properties of water during tissue irradiance with the FEL does not present an advantage to the cutting of cortical bone. The λ = 6.1 µm provided the highest ablation efficiency with deepest crater and the least amount of collateral thermal injury. Lasers Surg. Med. 39: 332–340, 2007. © 2007 Wiley‐Liss, Inc.
Novel Organic Activators for Single Site Iron Catalysts
Authors: Tudella Joana , Ribeiro Maria Rosário , Cramail Henri , Deffieux Alain 
Published: April 2007

AbstractThe synthesis of new organo‐aluminum derivatives based on the reaction of carboxylic acids with trialkylaluminum and their use as co‐catalysts for ethylene polymerization, in the presence of iron catalyst is described. These co‐catalysts were obtained through the reaction of acetic acid, benzoic acid, or benzoic acid derivatives with different trialkylaluminums. The most promising co‐catalyst was obtained from the reaction of benzene tricarboxylic acid (BTCA) with trimethylaluminum (TMA). The influence of alkylaluminum/BTCA ratio, reaction time, and temperature on the ethylene polymerization activity was investigated. 1H NMR spectra of some of the most active co‐catalysts confirm the formation of alumoxane‐type species.Polymerization activities of the same order or even higher to those found using “pure” trialkylaluminums or methylaluminoxane (MAO) co‐catalysts were obtained.magnified image
Zur Differentialgeometrie singulärer RIEMANNscher Räume
Authors: Dautcourt G. 
Published: April 2007

AbstractSinguläre RIEMANNsche Räume V mit einem metrischen Tensor gμv vom Matrixrang n — d (wobei 0 < d ≦ n) sind in mehrfacher Hinsicht in der allgemeinen Relativitätstheorie von Bedeutung. In die indefinite Raum‐Zeit eingebettet können sie im Falle n = 3, d = 1 als Ausbreitungsfronten ruhmasseloser Strahlung, als Welthorizonte usw. auftreten. Weniger geklärt ist ihre Rolle als spezielle, von den EINTEINschen Feldgleichungen erlaubte Typen von Singularitäten der Raum‐Zeit. Die hier gegebene differentialgeometrische Behandlung singulärer Räume beruht auf dem Umstand, daß ihre isotropen Richtungen ausgezeichnete Kurvenkongruenzen definieren. Mit ihnen läßt sich eine Klasse affiner Zusammenhänge angeben, die eine geeignete Verallgemeinerung des Lemmas von RICCI erfüllen. Lokale geometrische Eigenschaften sind dann mit Hilfe der zugehörigen RICCIschen Rotationskoeffizienten der Kurvenkongruenzen ausdrückbar, wie Reduzibilität bzw. totale Reduzibilität, die explizite Gestalt von Differentialinvarianten usw.
Surface Phase Separation and Morphology of Stimuli Responsive Complex Micelles
Authors: Ma Rujiang , Wang Beilei , Xu Yanling , An Yingli , Zhang Wangqing , Li Guiying , Shi Linqi 
Published: April 2007

AbstractComplex micelles with a P4VP core surrounded by a mixed PNIPAM/PEG shell were prepared by comicellization of PNIPAM93‐b‐P4VP58 and PEG114‐b‐P4VP58 in aqueous solutions. Increasing the temperature above the LCST of the PNIPAM induced a phase separation of the mixed shell due to the collapse of the PNIPAM block. The morphology of the collapsed PNIPAM was dependent on the composition of the mixed shell; a lower content of the PNIPAM resulted in separately distributed domains on the surface of the P4VP core, while a higher content of the PNIPAM led to the formation of continuous membrane around the P4VP core. When the continuous membrane was formed, the hydrophilic PEG block could connect the inner P4VP core and the outer milieu to form channels across the PNIPAM membrane for water and other small molecules to pass through.magnified image
Reversible Thermally Responsive and Luminescent Coil–Rod–Coil Triblock Copolymers
Authors: Xiao Xing , Fu Ya‐qin , Zhou Jian‐jun , Bo Zhi‐shan , Li Lin , Chan Chi‐Ming 
Published: April 2007

AbstractA functional coil–rod–coil triblock copolymer containing a terfluorene unit as the rigid segment and poly(N‐isopropylacrylamide) (PNIPAAm) as the flexible block was successfully synthesized via reversible addition–fragmentation chain‐transfer (RAFT) polymerization using terfluorene‐based dithioester as the RAFT agent. The temperature‐responsive optical properties were investigated with the aid of dynamic light scattering and fluorescence techniques. Additionally, the relationship between the optical properties and the reversible phase transition of the doping system formed by blending the copolymer with tetraphenylporphine tetrasulfonic acid was studied. Above the lower critical solution temperature, the energy transfer efficiency decreased as a result of the globule–to–coil transition from PNIPAAm segments. The result indicates that these copolymers have a potential to be used as responsive fluorescent probes in facile detection of dye‐labeled biopolymers.magnified image
STAT3: A critical transcription activator in angiogenesis
Authors: Chen Zhong , Han Zhong Chao 
Published: April 2007

AbstractAngiogenesis, the formation of new blood vessels from the pre‐existing vasculature, is a complex multistage process regulated by a number of signal transduction pathways. Accumulating evidence suggests that signal transducer and activator of transcription (STATs), mainly STAT3, play an important role in angiogenesis under both physiological and pathological conditions in addition to cell survival, proliferation, differentiation, and oncogenesis. STAT3, as a critical multifunctional mediator, regulates many aspects of angiogenesis at the transcriptional level. This review will highlight the pivotal role of STAT3 in well‐studied tumorous angiogenesis and cardiac angiogenesis, and summarize various potential mechanisms utilized by STAT3 to regulate the transcriptional activation of VEGF. © 2007 Wiley Periodicals, Inc. Med Res Rev, 28, No. 2, 185–200, 2008
Improving k‐t SENSE by adaptive regularization
Authors: Xu Dan , King Kevin F. , Liang Zhi‐Pei 
Published: April 2007

AbstractThe recently proposed method known as k‐t sensitivity encoding (SENSE) has emerged as an effective means of improving imaging speed for several dynamic imaging applications. However, k‐t SENSE uses temporally averaged data as a regularization term for image reconstruction. This may not only compromise temporal resolution, it may also make some of the temporal frequency components irrecoverable. To address that issue, we present a new method called spatiotemporal domain‐based unaliasing employing sensitivity encoding and adaptive regularization (SPEAR). Specifically, SPEAR provides an improvement over k‐t SENSE by generating adaptive regularization images. It also uses a variable‐density (VD), sequentially interleaved k‐t space sampling pattern with reference frames for data acquisition. Simulations based on experimental data were performed to compare SPEAR, k‐t SENSE, and several other related methods, and the results showed that SPEAR can provide higher temporal resolution with significantly reduced image artifacts. Ungated 3D cardiac imaging experiments were also carried out to test the effectiveness of SPEAR, and real‐time 3D short‐axis images of the human heart were produced at 5.5 frames/s temporal resolution and 2.4 × 1.2 × 8 mm3 spatial resolution with eight slices. Magn Reson Med 57:918–930, 2007. © 2007 Wiley‐Liss, Inc.
Wear of Tools Coated with Various PVD Films: Correlation with Impact Test Results by Means of FEM Simulations
Authors: Bouzakis Konstantinos‐Dionysios , Mirisidis Ioannis , Michailidis Nikolaos , Lili Eleftheria , Sampris Anastasios , Erkens Georg , Cremer Rainer 
Published: April 2007

AbstractThe use of appropriate cutting conditions and coatings is an issue of pivotal significance since it affects the overall tool performance in manufacturing processes. This paper introduces a quick and innovative procedure for characterizing the coating cutting performance based on the film impact resistance. A correlation between coating impact resistance and cutting performance under various conditions is established. Depending on the coated tool and the workpiece parameters, there are concrete cutting speed and feed rate regions, which can be effectively detected considering the previously mentioned correlation, leading to an enhanced cutting performance.magnified image
Antimicrobial films for food applications: a quantitative analysis of their effectiveness
Authors: Joerger Rolf D. 
Published: April 2007

AbstractA tremendous effort has been made over the last decade to develop and test films with antimicrobial properties to improve food safety and shelf life. This review catalogues and analyses the outcome of these research efforts. The bacteriocin nisin was the antimicrobial most commonly incorporated into films, followed by food‐grade acids and salts, chitosan, plant extracts, and the enzymes lysozyme and lactoperoxidase. The methodologies for measuring antimicrobial activity of both edible and inedible films varied considerably among the studies. Results, defined as the difference in the log10 colony‐forming unit (CFU) of a test organism exposed to a control film and the log10 CFU of the organism exposed to the antimicrobial film, ranged from 0 to 9 for many of the antimicrobials tested. Even for antimicrobials such as nisin, chitosan or antimicrobial acids with a ‘long’ history of studying their incorporation into antimicrobial films, the majority of results centred around 2 log10 reductions. The results suggest that antimicrobial films still face limitations and are perhaps still best viewed as part of a hurdle strategy to provide safe foods. Copyright © 2007 John Wiley & Sons, Ltd.