bluuebunny/crossref_metadata_2025_split huggingface dataset:
Oxidative stress induces senescence in chondrocytes
Authors: Brandl Anita , Hartmann Andreas , Bechmann Volker , Graf Bernhard , Nerlich Michael , Angele Peter 
Published: January 2011

AbstractCellular senescence is a program activated during diverse situations of cell stress. Chondrocytes differ from other somatic cells as articular cartilage is an avascular tissue. The effects of oxidative stress on chondrocytes are still unknown. Our studies were to investigate into the proliferation potential, cytological features and the telomere linked stress response system of human osteoarthritic chondrocytes, subjected to acute or prolonged oxidant challenge with hydrogen peroxide. Telomere length was measured using the telomere restriction fragment assay, gene expression was determined by RT‐PCR. Sub‐lethal doses of oxidative stress induced cell‐cycle arrest, senescent‐morphological features and senescence‐associated β‐galactosidase positivity. Prolonged oxidative treatment had no effects on cell proliferation or morphology. Sub‐lethal and prolonged low doses of oxidative stress considerably accelerated telomere attrition. The effects of sub‐lethal oxidative stress regarding proliferation and telomere biology were more distinct in senescent cells. Acute oxidant insult caused up‐regulation of p21 expression to levels comparable to senescent cells. TRF2 protects telomere ends and showed elevated expression levels. SIRT1 and XRCC5 enable cells to cope with unfavorable growing conditions. Both were up‐regulated after oxidant insult, but expression levels decreased in aging cells. Taken together, oxidative stress considerably accelerated telomere shortening and cellular aging in chondrocytes. Senescent cells showed a reduced tolerance to oxidative stress. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29: 1114–1120, 2011
Effect of organic amendments on uptake of selenium and biochemical grain composition of wheat and rape grown on seleniferous soils in northwestern India
Authors: Sharma Sucheta , Bansal Abhey , Dogra Ritu , Dhillon Surjit K. , Dhillon Karaj S. 
Published: February 2011

AbstractCrops grown in seleniferous soil may accumulate selenium (Se) to levels considered highly toxic for animal and human consumption. Furthermore, higher Se content in plant tissues leads to considerable deterioration in product quality. Application of organic amendments plays an important role in improving soil physical, chemical, and biological conditions and influencing nutrient availability. A field trial was conducted to evaluate the effect of organic amendments, namely poultry manure (PM), sugar cane press mud (SCPM), and farmyard manure (FYM), on Se uptake and grain quality of wheat and oilseed rape grown on a seleniferous soil in Punjab, India. Selenium accumulation by wheat and oilseed rape grains decreased significantly (75%–95%) with the application of PM and SCPM, while FYM application resulted in a significant decrease (23%) only in case of wheat grains. The amount of Se associated with seed proteins varied in proportion to its uptake under different treatments. Quality of wheat grains improved considerably with respect to total soluble sugars, reducing sugars, starch, lipids, and sulfur concentrations only after application of SCPM and PM. Treating a Se‐contaminated soil with organic amendments significantly increased the oil concentration and changed the proportion of various fatty acids in rape grains. It is concluded that applying organic amendments to Se‐contaminated soils can alleviate the deleterious effects of Se and restore the nutritional quality of grains.
Orthogonal array design for the optimization of ionic liquid‐based dispersive liquid–liquid microextraction of benzophenone‐type UV filters
Authors: Ye Lei , Liu Juanjuan , Yang Xin , Peng Yan , Xu Li 
Published: February 2011

AbstractIn the present study, dispersive liquid–liquid microextraction (DLLME) using an ionic liquid (IL) as the extractant was successfully developed to extract four benzophenone‐type UV filters from the different water matrices. Orthogonal array experimental design (OAD), based on five factors and four levels (L16(45)), was employed to optimize IL‐dispersive liquid–liquid microextraction procedure. The five factors included pH of sample solution, the volume of IL and methanol addition, extraction time and the amount of salt added. The optimal extraction condition was as follows. Sample solution was at a pH of 2.63 in the presence of 60 mg/mL sodium chloride; 30 μL IL and 15 μL methanol were used as extractant and disperser solvent, respectively; extraction was achieved by vortexing for 4 min. Using high‐performance liquid chromatography‐UV analysis, the limits of detection of the target analytes ranged between 1.9 and 6.4 ng/mL. The linear ranges were between 10 or 20 ng/mL and 1000 ng/mL. This procedure afforded a convenient, fast and cost‐saving operation with high extraction efficiency for the model analytes. Spiked waters from two rivers and one lake were examined by the developed method. For the swimming pool water, the standard addition method was employed to determine the actual concentrations of the UV filters.
Assessment of soil erosion in karst regions of Havana, Cuba
Authors: Febles‐González J.M. , Vega‐Carreño M.B. , Tolón‐Becerra A. , Lastra‐Bravo X. 
Published: January 2011

ABSTRACTOnly recently have erosion models begun to be used in research work in Cuba, specifically the USLE and the thematic cartography of factors in a GIS framework without using a specific model. It therefore becomes necessary to include simulation models for karst regions that make possible an integral assessment of the specific types of soil erosion in those environments and take into consideration the effects of climate change in soil management systems. Morphometric analysis of karst doline absorption forms in regions of La Habana Province in 1986, 1997, and 2009 allowed the characterisation and application of the Morgan Morgan Finney (MMF) conceptual empirical erosion model in the Country for the first time. The results showed previously unreported losses of 12·3–13·7 t of soil ha −1 y−1, which surpasses the permissible erosion threshold. Furthermore, it clearly shows the unsustainable trend of Red Ferralitic and Ferrasol Rhodic (World Reference Base) soils use. The model applied considered the effects of extreme rainfall events associated with climate change in recent years. The results found have led to strategies for coping with future climate change in each scenario and have made it possible to evaluate the consequences. Copyright © 2011 John Wiley & Sons, Ltd.
Classical and quantum control of electrons using the carrier‐envelope phase of strong laser fields
Authors: Abel M. , Neumark D.M. , Leone S.R. , Pfeifer T. 
Published: February 2011

AbstractElectrons are among the lightest quantum particles in nature, yet they are of paramount importance in any kind of chemical reaction as they are the essence of molecular bonds. For several years, laser fields have been used towards the final goal of controlling chemical reaction dynamics. While early experiments focused mainly on the control of the internuclear wavefunction of rather heavy molecules, advances in short‐pulse laser technology now allow the control of lighter molecules all the way down to hydrogen and even the direct control of electrons and their quantum wavefunctions. In this context, the stabilization and control of the carrier‐envelope phase (CEP) of laser pulses has been one of the crucial technological advances that set off a revolution in ultrafast laser science. The authors review and summarize some of the past and current experimental achievements and theoretical ideas on CEP laser control of electrons. It will become clear that in some cases, depending on the control scenario, electrons can be considered to behave as classical particles and the control of their trajectories follow the laws of classical Newtonian mechanics while in other cases, the quantum nature of electrons is directly exploited to steer electron dynamics by means of quantum interference.
Hot dip galvanizing behavior of advanced high strength steel
Authors: Li F. , Liu H. , Shi W. , Liu R. , Li L. 
Published: February 2011

AbstractThis work studied the hot dip galvanizing behavior of three advanced high strength steels annealed under different protective atmospheres. The coating quality, surface oxides, and the mechanical property of steel matrix were examined. The experimental results show that annealing atmosphere can influence the galvanizability and thermodynamics calculation can predict the surface selective oxidation. It was shown for the first time in this work that annealing atmosphere may also influence the mechanical property of the steel matrix.
Transformation/dissolution studies on the release of iron and chromium from particles of alloys compared with their pure metals and selected metal oxides
Authors: Hedberg Y. , Wallinder I. Odnevall 
Published: February 2011

AbstractTransformation/dissolution (T/D) data for different Cr‐ and Fe‐based alloys (a FeCr alloy, stainless steel AISI 316L, an alloy side product (SP) from stainless steel production) compared with their pure metals (Cr, Fe) and selected metal oxides (Cr2O3, Fe3O4) was generated and is used throughout the entire REACH assessment documentation of chromium metal and ferrochromium alloys to derive conclusions regarding their acute and chronic ecotoxicity hazard classification.Short and long term tests were conducted to assess data for acute and chronic aquatic toxicity following the recognized standardized T/D protocol. Tests were performed in media of different pH (pH 6.0 and pH 8.0), time periods, and solution composition, also investigating the effect of different experimental parameters.Generated data elucidates the complexity of the metal release process and its dependence on many interacting material‐, surface‐, and experimental factors as well as on the chemistry of the metal–water system being metal species specific. It is evident that the extent of metal release cannot be predicted by either the bulk or the surface composition, and that metal speciation measurements of released metals are essential to assess aquatic toxicity induced by metal/alloy particles. Observed released Fe and Cr concentrations were significantly lower than reported acute and chronic ecotoxicological endpoints.
The effect of absorbed hydrogen on the corrosion behavior of sintered NdFeB magnet
Authors: Yang H. , Mao S. , Song Z. 
Published: February 2011

AbstractThe absorption of hydrogen by NdFeB magnet has been investigated by using the electrochemical charging technique at constant cathodic current density Ic ranging from 0 to 4 mA/cm2. Open circuit potential measurements (OCP) and polarization curves were carried out to study the corrosion behavior of the charged NdFeB magnet in 0.01 mol/L NaCl solution. The results showed that hydrogen had a strong influence on the corrosion of NdFeB magnet. The open circuit potential became gradually negative due to the hydrogen incorporation into the NdFeB magnet. The corrosion resistance was reduced gradually with the increasing cathodic current density Ic. The surface structure and the morphology of the charged NdFeB magnet were examined by XRD and SEM. The results revealed that the effect of the absorbed hydrogen focused mostly on accelerating the exfoliation corrosion of Nd2Fe14B matrix grain.
Preparation and characterization of inorganic and organic coatings on AZ91D magnesium alloy with electroless plating pretreatment
Authors: Zhang S. Y. , Li Q. , Yang X. K. , Zhang H. X. , Wang S. Y. , Liu F. 
Published: February 2011

AbstractIn this paper, a protective coating scheme was applied for the corrosion protection of AZ91D magnesium alloy. Electroless Ni coating (EN coating) as bottom layer, electrodeposited Ni coating (ENN coating), and silane‐based coating (ENS coating) as top layer, respectively, were successfully prepared on AZ91D magnesium alloy by combination techniques. Scanning electron microscopy and X‐ray diffraction were employed to investigate the surface and phase structure of coatings, respectively. The electrochemical corrosion behaviors of coatings in neutral 3.5 wt% NaCl solution were evaluated by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization techniques. The corrosion testing showed that the three kinds of coatings all could provide corrosion protection for AZ91D magnesium alloy to a certain extent, and the corrosion resistance of ENN and ENS was superior to EN. In order to further study the corrosion protection properties of ENN and ENS, a comparative investigation on the evolution of EIS of ENN and ENS was carried out by dint of immersion test in neutral 3.5 wt% NaCl solution. The results indicated that, compared with ENN, the ENS could provide longer corrosion protection for AZ91D magnesium alloy. It is significant to determine the barrier effect of each coating, which could provide reference for industry applications.
A zinc/silicon dioxide composite film: Fabrication and anti‐corrosion characterization
Authors: Lin Z. F. , Zhang D. , Wang Y. , Wang P. 
Published: February 2011

AbstractA zinc/silicon dioxide composite film has been electrodeposited on carbon steel surface via adding tetraethylorthosilicate (TEOS) in zinc nitrate solution. The advantage of this method is that the metal/inorganic composite film can be fabricated without adding solid particles in solution. Polarization curve results showed that the composite film obtained at a TEOS concentration of 0.012 M had the best corrosion resistance. Electrochemical impedance spectroscopy results indicated that this film had a corrosion protection effect in 3.5 wt% sodium chloride solution for hundreds of hours. This kind of composite film can be potentially applied as anti‐corrosion coating for metal corrosion protection.
Magnetic properties of multi‐walled carbon nanotubes modified with cobalt
Authors: Grechnev G.E. , Desnenko V.A. , Fedorchenko A.V. , Panfilov A.S. , Prylutskyy Y.I. , Grybova M.I. , Matzui L.Y. , Ritter U. , Scharff P. , Kolesnichenko Y.A. 
Published: February 2011

AbstractMagnetic properties of multi‐walled carbon nanotubes (MWCNT) modified with cobalt were studied in detail in the temperature range (4.2–290) K. MWCNT which encapsulate Co nanoparticles were obtained using CVD methods. The low temperature SQUID magnetization measurements were supplemented by structural investigations with thermogravimetric analysis, HRTEM and SEM.Die magnetischen Eigenschaften von mit Kobalt‐modifizierten mehrwandigen Kohlenstoffnanoröhren (MWCNT) wurden im Detail in einem Temperaturbereich von 4,2 bis 290 K untersucht. Die MWCNT mit Kobalteinschlüssen wurden durch CVD Methoden erhalten. Die bei niedrigen Temperaturen gemessenen SQUID Magnetisierungen konnten durch Strukturuntersuchungen mit thermogravimetrischen Analysen und Rasterelektronenmessungen ergänzt werden.
Variation of defect spectra in Si ionizing radiation detectors depending on irradiation
Authors: Kalendra V. , Kažukauskas V. , Vainorius N. , Vaitkus J. V. , Bozhko V. 
Published: February 2011

AbstractThe defect properties of Si ionizing radiation detectors were investigated depending on the irradiation by high energy neutrons. The investigations were performed in the framework of WODEAN project of CERN‐RD50 collaboration. The p+‐n‐n+ samples were irradiated with the fluencies 1·1013 to 1·1016 n/cm2. The photoconductivity spectra indicated that upon irradiation deep levels below the middle of the band gap were created. Their activation energies were 0.49–0.52 eV, 0.77–0.81 eV, 0.88–0.91 eV, and 1.02–1.11 eV. The effective densities of these levels were depending on the fluencies and on the isochronal thermal treatments at low temperatures. The variations of the defect level population induced by annealing have been compared with the steady state lifetimes and photoconductivity decay constants.Die Defekteigenschaften von Si‐Detektoren für ionisierende Strahlung wurden in Abhängigkeit von der Bestrahlung durch hochenergetische Neutronen untersucht. Die Untersuchungen wurden im Rahmen des Projekts WODEAN der CERN‐RD50 Kollaboration durchgeführt. Die p+‐n‐n+ Proben wurden mit Flussdichten von 1·1013 bis 1·1016 n/cm2 bestrahlt. Die Photoleitfähigkeitsspektren ergaben, dass bei der Bestrahlung tiefe Niveaus unterhalb der Mitte der Bandlücke erzeugt wurden. Die Aktivierungsenergien dieser Niveaus betragen 0,49 bis 0,52 eV, 0,77 bis 0,81 eV, 0,88 bis 0,91 eV und 1,02 bis 1,11 eV. Die effektiven Dichten dieser Niveaus hängen sowohl von der Flussdichte als auch von der isochron thermischen Behandlung bei niedrigen Temperaturen ab. Die Variation der Besetzung des Niveaus durch Erhitzen wurde mit den Gleichgewicht‐Lebensdauern und den Photoleitfähigkeit‐Abbaukonstanten verglichen.
A comparative STM‐investigation of monolayers of n‐alkanes and arachidic acid on the liquid tetradecane‐graphite interface
Authors: Senenko A.I. , Stryzheus. D.V. , Marchenko A.A. , Naumovets A.G. 
Published: February 2011

AbstractHighly ordered monolayer films of an n‐alkane and arachidic acid were deposited on graphite surface from their solutions in n‐tetradecane, and their molecular structure was investigated by scanning tunneling microscopy. Close‐packed lamella‐like structures with long range order were observed. In alkane monolayers, each lamella is composed by single molecules, while in the case of acid, lamellas consist of dimers formed by acid molecules due to interaction between their carboxylic groups, probably via hydrogen bonds. An increased brightness of carboxyl head in each fifth acid molecule was observed, which is attributed to nonequivalent positions of acid molecules with respect to the substrate carbon atoms.Hochgeordnete Monoschichtfilme von einem n‐Alkan und von Arachidonsäure wurden auf einer Graphitoberfläche aus Lösungen in n‐Tetradecan abgeschieden und ihre Molekularstruktur wurde untersucht. Beobachtet wurden dichtgepackte lamellenartigen Strukturen mit weitreichender Ordnung. In Alkan‐Monoschichten besteht jede Lamelle aus einzelnen Molekülen, während bei Säuren die Lamellen aus Dimerenbestehen, die aus Säuremolekülen über die Wechselwirkung zwischen ihren Carboxylgruppen gebildet wurden, wahrscheinlich durch Wasserstoffbrückenbindung. Eine verstärkte Helligkeit des Carboxylat‐Endes wurde in jedem fünften Säuremolekül beobachtet, was für nichtäquivalente Position von Säuremolekülen in Bezug auf einer Schichtunterlage aus Kohlenstoffatomen typisch ist.
Effect of flavonoids on basal and insulin‐stimulated 2‐deoxyglucose uptake in adipocytes
Authors: Claussnitzer Melina , Skurk Thomas , Hauner Hans , Daniel Hannelore , Rist Manuela J. 
Published: January 2011

AbstractScope: The adipose tissue is a major site of insulin action and contributes substantially to energy homeostasis. Insulin increases the extraction of glucose from circulation into adipose tissue by recruiting the glucose transporter GLUT4 to the plasma membrane. It has been proposed that dietary flavonoids may interfere with glucose transport processes.Methods and results: We have used murine 3T3‐L1 adipocytes and isolated mature human adipocytes to assess the interaction of selected flavonoids with glucose uptake, both in the basal state and after insulin stimulation. Kinetic characterization of 2‐deoxyglucose uptake in the basal state revealed in both cell types an apparent Km of around 8 mM with no change in affinity but a significant increase in maximal influx in the presence of insulin. A screening of representative flavonoids of different structural classes revealed the flavanone naringenin and the isoflavone daidzein to affect glucose transport significantly with half‐maximal inhibition at concentrations of around 60–80 μM for basal and 70–110 μM for insulin‐stimulated glucose uptake in both 3T3‐L1 adipocytes and mature human adipocytes.Conclusion: Considering attainable plasma concentrations of flavonoids in vivo, we assume that even under physiological conditions naringenin and daidzein could impair glucose removal from plasma, which may pose a risk to patients with diabetes mellitus.
Stabilization of small heterodimer partner mRNA by grape seed procyanidins extract in cultured hepatocytes
Authors: Inoue Jun , Tanaka Minako , Nanmoku Manami , Yashiro Takuya , Sato Ryuichiro 
Published: January 2011

AbstractScope: Consumption of dietary grape seed procyanidins extract (GSPE) has improved the plasma lipid profile in humans and experimental animals. The effect of GSPE on the reduction of the postprandial plasma triglyceride (TG) levels has been attributed to the activation of the small heterodimer partner (SHP). GSPE increases SHP gene expression in rat liver and the TG‐lowering effect of GSPE is abolished in SHP‐deficient mice. However, the mechanism by which GSPE increases SHP mRNA levels remains unclear. This study addressed the effect of GSPE on SHP mRNA stability.Methods and results: The present study shows for the first time that SHP mRNA is rapidly degraded, as measured by actinomycin D‐based mRNA chase experiments, and GSPE transiently stabilizes SHP mRNA in HepG2 cells. This degradative effect was completely abolished with 2 h of prolonged treatment with GSPE. However, treatment of fresh HepG2 cells with a pretreated GSPE‐containing medium also stabilized SHP mRNA, indicating that GSPE inactivation is not responsible for the transient effects that GSPE has on SHP mRNA stability.Conclusion: SHP expression is intricately controlled by mRNA stabilization, which is transiently increased by GSPE, along with at the transcriptional and posttranslational levels.
Evaluation of periodic electrodiagnostic measurements to monitor motor recovery after different peripheral nerve lesions in the rat
Authors: Korte Nele , Schenk Henning C. , Grothe Claudia , Tipold Andrea , Haastert‐Talini Kirsten 
Published: January 2011

AbstractIntroduction:The advantage of minimally invasive electrodiagnostic methods for periodic evaluation of reinnervation at predefined time intervals does not seem to be widely recognized. In this study, using a rat model, we assessed the utility of periodic electrodiagnostic measurements for monitoring ongoing motor recovery after peripheral nerve injuries of differing severity.Methods:In a comparative study, either unilateral sciatic nerve crush injury (n = 10), end‐to‐end coaptation (n = 5), or 10‐mm nerve autotransplantation (n = 10) were performed. During the 6–16‐week period thereafter compound muscle action potentials (CMAPs) were recorded percutaneously every week in anesthetized animals. Motor nerve conduction velocity and percentage of axon loss were calculated and compared with footprint analyses (static sciatic index, SSI) and evaluations of sensory recovery.Results:Our results clearly demonstrate that, although SSI measurements reliably demonstrated progress of regeneration after nerve crush injury only, differences in electrodiagnostically determined values precisely remodeled differences in axonal regeneration, which was confirmed by histomorphometric analysis of axonal regeneration.Conclusions:Percutaneous electrodiagnostic measurements enable reliable estimation of axonal regeneration parameters such as myelination and nerve fiber density and display in close proximity the actual status of axonal regeneration. Muscle Nerve 44: 63–73, 2011