bluuebunny/crossref_metadata_2025_split huggingface dataset:
Extracellular enzymes in sludge flocs collected at 14 full‐scale wastewater treatment plants
Authors: Yu Guanghui , He Pinjing , Shao Liming , Lee Duujong 
Published: July 2008

AbstractBACKGROUND: Extracellular enzymes and chemical composition of sludge flocs affect the wastewater treatment capability. Here a fractionation protocol is presented describing the distributions of extracellular enzymes, proteins (PN) and polysaccharides (PS) in sludge flocs. Sludge floc samples collected from 14 full‐scale wastwater treatment plants (WWTPs), including those treating sewage, leachate and industrial wastewaters, were fractionated through centrifugation and ultrasound into five fractions: (1) supernatant; (2) slime; (3) loosely bound extracellular polymeric substances (LB‐EPS); (4) tightly bound EPS (TB‐EPS); and (5) pellets.RESULTS: The distributions of extracellular enzymes, PN and PS in different types of sludge flocs were almost identical. Considerable quantities of α‐amylase were bound with the pellet fraction, while the remainder was uniformly dispersed over the sludge matrix. Conversely, alkaline phosphatase, acid phosphatase and protease bound mainly with the pellet and TB‐EPS fractions.CONCLUSION: The enzyme activities distributed in sludge flocs achieved from 14 full‐scale WWTPs revealed a non‐wastewater‐specific manner. This work for the first time demonstrated that the activities of enzymes correlated with the characteristics of the wastewaters treated, and raised the possibility of manipulating the hydrolysis reactions using process parameters. Copyright © 2008 Society of Chemical Industry
Sieve‐based device for MALDI sample preparation. I. Influence of sample deposition conditions in oligonucleotide analysis to achieve significant increases in both sensitivity and resolution
Authors: Molin Laura , Cristoni Simone , Crotti Sara , Bernardi Luigi Rossi , Seraglia Roberta , Traldi Pietro 
Published: July 2008

AbstractSpraying of oligonucleotide‐matrix solutions through a stainless steel (ss) sieve (38 µm, 450 mesh) leads to the formation, on the matrix‐assisted laser desorption/ionization (MALDI) sample holder, of uniformly distributed microcrystals, well separated from each other. When the resulting sample holder surface is irradiated by laser, abundant molecular species form, with a clear increase in both intensity and resolution with respect to values obtained by ‘Dried Droplet’, ‘Double Layer’, and ‘Sandwich’ deposition methods. In addition, unlike the usual situation, the sample is perfectly homogeneous, and identical spectra are obtained by irradiating different areas. On one hand, the data indicate that this method is highly effective for oligonucleotide MALDI analysis, and on the other, that it can be validly employed for fully automated MALDI procedures. Copyright © 2008 John Wiley & Sons, Ltd.
Mass and lifetime measurements of exotic nuclei in storage rings
Authors: Franzke Bernhard , Geissel Hans , Münzenberg Gottfried 
Published: July 2008

AbstractMass and lifetime measurements lead to the discovery and understanding of basic properties of matter. The isotopic nature of the chemical elements, nuclear binding, and the location and strength of nuclear shells are the most outstanding examples leading to the development of the first nuclear models. More recent are the discoveries of new structures of nuclides far from the valley of stability. A new generation of direct mass measurements which allows the exploration of extended areas of the nuclear mass surface with high accuracy has been opened up with the combination of the Experimental Storage Ring ESR and the FRragment Separator FRS at GSI Darmstadt. In‐flight separated nuclei are stored in the ring. Their masses are directly determined from the revolution frequency. Dependent on the half‐life two complementary methods are applied. Schottky Mass Spectrometry SMS relies on the measurement of the revolution frequency of electron cooled stored ions. The cooling time determines the lower half‐life limit to the order of seconds. For Isochronous Mass Spectrometry IMS the ring is operated in an isochronous ion‐optical mode. The revolution frequency of the individual ions coasting in the ring is measured using a time‐of‐flight method. Nuclides with lifetimes down to microseconds become accessible. With SMS masses of several hundreds nuclides have been measured simultaneously with an accuracy in the 2 × 10−7‐range. This high accuracy and the ability to study large areas of the mass surface are ideal tools to discover new nuclear structure properties and to guide improvements for theoretical mass models. In addition, nuclear half‐lives of stored bare and highly charged ions have been measured. This new experimental development is a significant progress since nuclear decay characteristics are mostly known for neutral atoms. For bare and highly charged ions new nuclear decay modes become possible, such as bound‐state beta decay. Dramatic changes in the nuclear lifetime have been observed in highly charged ions compared to neutral atoms due to blocking of nuclear decay channels caused by the modified atomic interaction. High ionization degrees prevail in hot stellar matter and thus these experiments have great relevance for the understanding of the synthesis of elements in the universe and astrophysical scenarios in general. © 2008 Wiley Periodicals, Inc., Mass Spec Rev 27: 428–469, 2008
Femtosecond laser ablation inductively coupled plasma mass spectrometry: Fundamentals and capabilities for depth profiling analysis
Authors: Pisonero Jorge , Günther Detlef 
Published: July 2008

AbstractLaser ablation coupled to inductively coupled plasma mass spectrometry has become a versatile and powerful analytical method for direct solid analysis. The applicability has been demonstrated on a wide variety of samples, where major, minor, and trace element concentrations or isotope ratio determinations have been of interest. The pros and cons of UV‐nsec laser ablation have been studied in detail, and indicate that aerosol generation, aerosol transport, and aerosol excitation–ionization within the ICP contribute to fractionation effects, which prevent this method from a more universal application to all matrices and all elements. Recent progresses in IR‐fs and UV‐fs laser ablation coupled to ICP‐MS have been reported, which increase the inter‐matrix and multi‐element quantification capabilities of this method. These fundamental improvements in LA‐ICP‐MS are of significant importance for entering new applications in material science and related research fields. In particular, because coatings (conducting and non‐conducting) consist of single or multilayers of various elemental composition and of different thickness (nm–mm range), significant progress in the field of depth profiling with fs‐laser ablation can be expected. Therefore, in‐depth profile analysis of polymers, semiconductors, and metal sample investigations, using ultra‐fast laser ablation for sampling and the currently achievable figures of merit, are discussed. In this review manuscript, the enhanced capabilities of fs‐LA‐ICP‐MS for direct solid sampling are highlighted, and it is discussed about current methods used for quantitative analysis and depth profiling, the ablation process of UV‐ns and UV‐fs, the influence of the laser beam profile, aerosol structure and transport efficiency, as well as the influence of the ICP‐MS (e.g., vaporization and ionization efficiency in the plasma, and type of mass analyzer). © 2008 Wiley Periodicals, Inc., Mass Spec Rev 27: 609–623, 2008
Mass spectrometry in systems biology: An overview
Authors: Feng Xiaojun , Liu Xin , Luo Qingming , Liu Bi‐Feng 
Published: July 2008

AbstractAs an emerging field, systems biology is currently the talk of the town, which challenges our philosophy in comprehending biology. Instead of the reduction approach advocated in molecular biology, systems biology aims at systems‐level understanding of correlations among molecular components. Such comprehensive investigation requires massive information from the “omics” cascade demanding high‐throughput screening techniques. Being one of the most versatile analytical methods, mass spectrometry has already been playing a significant role at this early stage of systems biology. In this review, we documented the advances in modern mass spectrometry technologies as well as nascent inventions. Recent applications of mass spectrometry‐based techniques and methodologies in genomics, proteomics, transcriptomics and metabolomics will be further elaborated individually. Undoubtedly, more applications of mass spectrometry in systems biology can be expected in the near future. © 2008 Wiley Periodicals, Inc., Mass Spec Rev 27: 635–660, 2008
Identifying patterns of adverse event reporting for four members of the angiotensin II receptor blockers class of drugs: revisiting the Weber effect
Authors: McAdams Mara A. , Governale Laura A. , Swartz Lynette , Hammad Tarek A. , Dal Pan Gerald J. 
Published: July 2008

AbstractPurposeTo evaluate the evidence for temporal reporting patterns, such as the Weber effect, in spontaneous post‐marketing adverse event (AE) reports submitted to the Food and Drug Administration (FDA), for four members of the angiotensin II receptor blockers drug class (ARBs).MethodsFor losartan, valsartan, irbesartan, and candesartan, we evaluated temporal trends in reporting for the total number of AE reports, serious AE reports, and direct reports from consumers or health care providers (direct reports) to FDA. Reporting patterns were considered consistent with the Weber effect when the peak occurred 2 years after US marketing and the number of reports declined thereafter. We tabulated the number of reports by year since the first report. We adjusted the total number of reports, number of serious AE reports, and number of direct reports by the number of US dispensed prescriptions.ResultsThere were no clear temporal reporting patterns for the total number of reports, direct reports, or serious AE reports. We observed a consistent trend for the adjusted number of direct and serious AE reports. The adjusted number was highest in the first year and continually decreased over time for all four ARBs. For the adjusted total number of reports, the decline was not constant over time.ConclusionA characteristic temporal pattern in the adjusted number of reports, in which the adjusted number was highest in the first year and declined thereafter, was identified. However, we did not observe a pattern consistent with the Weber effect for these four ARBs. Copyright © 2008 John Wiley & Sons, Ltd.
Genome‐wide enzyme annotation with precision control: Catalytic families (CatFam) databases
Authors: Yu Chenggang , Zavaljevski Nela , Desai Valmik , Reifman Jaques 
Published: July 2008

AbstractIn this article, we present a new method termed CatFam (Catalytic Families) to automatically infer the functions of catalytic proteins, which account for 20–40% of all proteins in living organisms and play a critical role in a variety of biological processes. CatFam is a sequence‐based method that generates sequence profiles to represent and infer protein catalytic functions. CatFam generates profiles through a stepwise procedure that carefully controls profile quality and employs nonenzymes as negative samples to establish profile‐specific thresholds associated with a predefined nominal false‐positive rate (FPR) of predictions. The adjustable FPR allows for fine precision control of each profile and enables the generation of profile databases that meet different needs: function annotation with high precision and hypothesis generation with moderate precision but better recall. Multiple tests of CatFam databases (generated with distinct nominal FPRs) against enzyme and nonenzyme datasets show that the method's predictions have consistently high precision and recall. For example, a 1% FPR database predicts protein catalytic functions for a dataset of enzymes and nonenzymes with 98.6% precision and 95.0% recall. Comparisons of CatFam databases against other established profile‐based methods for the functional annotation of 13 bacterial genomes indicate that CatFam consistently achieves higher precision and (in most cases) higher recall, and that (on average) CatFam provides 21.9% additional catalytic functions not inferred by the other similarly reliable methods. These results strongly suggest that the proposed method provides a valuable contribution to the automated prediction of protein catalytic functions. The CatFam databases and the database search program are freely available at http://www.bhsai.org/downloads/catfam.tar.gz. Proteins 2009. © 2008 Wiley‐Liss, Inc.
Dipolar interaction in ordered superlattices of ferromagnetic nanoparticles
Authors: Tartakovskaya Elena V. , Vovk Andriy , Golub Vladimir 
Published: July 2008

AbstractAn analytic expression is derived in the real space representation for the demagnetizing factors of long stripes and finite dots of rectangular cross section. The result depends on the arrangement in corresponding superlattices of nanoparticles. The influence of the demagnetizing factors on dynamical properties of nanoparticle arrays is discussed. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Approximation of magnetic behavior of complex nanomagnetic materials, using the “P ” curves for structural characterization of magnetic suspensions
Authors: Popa N. C. , Siblini A. , Rousseau J. J. , Blanc‐Mignon M.‐F. , Chatelon J. P. 
Published: July 2008

AbstractThe “P ” curves for the structural characterization of magnetic nanoparticles suspensions (complex fluids, complex powders, complex composite materials, or living biological materials having magnetic properties) are the graphical representation of the first derivative (relative to the magnetic field strength H) of the magnetization curve relative to its saturation magnetization. In the case of the above materials, the magnetic properties are conferred to various carrier liquids by artificially integrating in their structure ferromagnetic particles of different sizes. The magnetic properties are usually shown by the hysteresis curve. The structure can be seen by (electronic) micrography. The P curves offer another possibility to determine the structure of the magnetic component of a complex fluid by numerical analysis of the magnetization curve experimentally obtained. Starting from these P curves, the paper presents the possibility to approximate the magnetic behavior of these complex nanomagnetic materials. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Half‐metallicity and magnetism at Heusler alloy surfaces: Co2MSi(001) (M = Ti, Cr)
Authors: Jin Ying Jiu , Lee Jae Il 
Published: July 2008

AbstractWe investigated the electronic structures, magnetism, and half‐metallicity at the (001) surfaces of full‐Heusler alloys, Co2MSi (M = Ti, Cr), by using the all‐electron full‐potential linearized augmented plane wave method within the generalized gradient approximation. Both the Co‐terminated (Co‐term) and the MSi‐terminated (MSi‐term) surfaces were considered. From the calculated atom‐resolved density of states, we found that the half‐metallicity was destroyed at the Co‐term surfaces for both alloys. The electronic structures at the MSi‐term surfaces of the two alloys showed much different behavior. The half‐metallicity was retained at the TiSi‐term for Co2TiSi(001) but the minority spin gap was much reduced due to surface states located just below the Fermi level. On the other hand the half‐metallicity was destroyed at the CrSi‐term of Co2CrSi(001) due to the surface states located at the Fermi level. The calculated magnetic moment of the surface Co atom of the Co‐term for Co2CrSi(001) was increased slightly to 1.05μB with respect to that of the deep inner layers (∼1.00μB), while that for Co2TiSi(001) was decreased to 0.88μB. Large enhancement of the magnetic moment was found for the surface Ti atoms at TiSi‐term of Co2TiSi(001) and Cr atoms at CrSi‐term of Co2CrSi(001) with values of 0.07μB and 2.91(B, respectively. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electronic and magnetic properties of digitally Ti doped InP: A first principles study
Authors: Rahman Gul , Cho Sunglae , Hong Soon Cheol 
Published: July 2008

AbstractUsing the full‐potential linearized augmented plane wave method within the generalized gradient approximation, we study the electronic and the magnetic properties of digitally Ti doped InP. It is quite interesting that digitally Ti‐doped InP system shows half metallic ferromagnetism even though both bulk zinc blende TiP and InP are paramagnetic. We also investigate the electronic and the magnetic properties as a function of spacer layer thickness. Their properties such as exchange coupling constant and atomic projected density of states are more or less independent of the InP thickness. Spin density contour maps indicate that the spin‐polarization is confined within the TiP plane. The system may show a highly anisotropic property in spin‐polarized transport. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Monte Carlo study of the exchange bias and the training effect in nanoparticles with core/shell morphology
Authors: Vasilakaki M. , Eftaxias E. , Trohidou K. N. 
Published: July 2008

AbstractWe have employed the Monte Carlo (MC) simulation method to study at an atomic level the exchange bias effect, the vertical shift and the training effect observed in nanoparticles consisting of a ferromagnetic (FM) core and an antiferromagnetic (AFM) shell. Heisenberg exchange interaction is assumed between the spins in the ferromagnetic core, in the AFM shell and along the FM/AFM interface. We have demonstrated that the interface exchange interaction together with a strong interface anisotropy results in an exchange bias field (Hex) and a strong coercive field (Hc). Our simulations show that while the interface is responsible for the exchange bias, in the vertical shift we have a contribution from the whole shell of the nanoparticles. In the training effect we have a contribution from the interface and we can also have a contribution from the core and the shell depending on the particle size. The shape of the Hc(T) and Hex(T) curves depends on the type and the strength of the shell anisotropy. Using the MC simulations, we have also studied the effect of interparticle dipolar interactions in the exchange bias properties of an assembly of FM core/AFM shell nanoparticles for different nanoparticle densities. We show that these interactions result in a decrease of the coercive field and an increase of the exchange bias field with the concentration of the assembly. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Preparation and characterization of sprayed In2O3:Mo films
Authors: Prathap P. , Gowri Devi G. , Subbaiah Y. P. V. , Ganesan V. , Ramakrishna Reddy K. T. , Yi J. 
Published: July 2008

AbstractTransparent conducting oxides (TCO) play a major role in the area of thin film photovoltaics, flat panel displays, organic light emitting diodes and other optoelectronic devices. In order to improve the performance of a device, the TCO should have good optical transmittance as well as conductivity. In the present study, In2O3:Mo films have been grown by an economic and simple spray pyrolysis method with different molybdenum doping concentrations that vary in the range, 0–12 at% at a substrate temperature of 400 °C. The structural and morphological, electrical and optical behaviour of the as‐grown layers were studied. All the deposited layers showed a body‐centered cubic structure with a strong (222) orientation. In2O3:Mo films grown with Mo‐concentration of 6.0 at% had the maximum grain size of 90 nm. The average optical transmittance of the films was >85% in the visible region. The change of grain size, electrical resistivity, carrier mobility and density, optical band gap and figure of merit with doping concentration was reported and discussed. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Tunable optical properties of laser grown double‐structures with gold nanoparticlesand zinc oxide thin films
Authors: György E. , Pérez del Pino A. , Giannoudakos A. , Kompitsas M. , Mihailescu I. N. 
Published: July 2008

AbstractGold nanoparticles on zinc oxide thin films surfaces have been synthesized by means of two step pulsed laser deposition. Zinc and gold targets were subsequently submitted to pulses generated by an UV KrF* (λ = 248 nm, τFWHM ≅ 20 ns, ν = 2 Hz) excimer, as well as a frequency tripled Nd:YAG (λ = 355 nm, τ ∼ 10 ns) laser sources. The obtained structures surface morphology, crystalline quality, and chemical composition depth profile were investigated by acoustic (dynamic) mode atomic force microscopy, X‐ray diffraction, and wavelength dispersive X‐ray spectroscopy. The corresponding absorption and reflection spectra were recorded with the aid of a double beam spectrophotometer. The results proved the possibility to tailor the gold/zinc oxide nanostructures optical properties through the proper choice of the growth parameters, i.e. number of laser pulses used for the ablation of the gold targets as well as nature of the substrate material. The tunable optical features in the visible‐near infrared spectral region allow for the design of gold/zinc oxide nanostructures with pre‐defined optical characteristics. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Sensitivity of ZnO films doped with Er, Ta and Co to NH3 at room temperature
Authors: Dimova‐Malinovska D. , Nichev H. , Georgieva V. , Angelov O. , Pivin J.‐C. , Mikli V. 
Published: July 2008

AbstractThe sensitivity of ZnO films, undoped and doped with Er, Ta and Co, to exposure to NH3 has been studied. The films were deposited by magnetron co‐sputtering of a sintered ZnO target with chips of the different doping elements on its surface. The sensitivities of the ZnO films to exposure to NH3 were measured by the quartz crystal microbalance method using the resonance frequency shift. The adsorption process was investigated over an aqueous solution of ammonia with 100 ppm concentration. The speed and the mass of sorption were calculated on the basis of the time–frequency characteristic. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Study of photocatalytic activity in sputter‐deposited Cr‐TiO2 thin film
Authors: Biswas S. , Hossain M. F. , Takahashi T. , Kubota Y. , Fujishima A. 
Published: July 2008

AbstractIn this investigation, Cr‐doped TiO2 thin films were prepared on glass substrate with various doping concentrations to study the photocatalytic activity in UV–visible light irradiation. The Cr‐doped TiO2 thin films were prepared by reactive magnetron sputtering using various sputtering pressures to control the Cr doping concentration. The optical property shows large red‐shift of transmittance edge and decrease of average transmittance with the increase of Cr doping. The photocatalytic activity, evaluated by the measurement of decomposition of methanol under visible and UV–visible light irradiation, increases for the low Cr doping concentration, but decreases for higher Cr doping concentrations. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)