bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determination of binding sites in carboplatin‐bound cytochrome c using electrospray ionization mass spectrometry and tandem mass spectrometry
Authors: Yang Gaosheng , Miao Ren , Jin Chen , Mei Yuhua , Tang Huiwei , Hong Jin , Guo Zijian , Zhu Longgen 
Published: June 2005

AbstractInteraction of carboplatin with cytochrome c (Cyt. c) has been investigated by electrospray ionization mass spectrometry (ESI‐MS) and tandem mass spectrometry (MS/MS). ESI‐MS studies revealed that the ring‐opened adducts of carboplatin with Cyt. c were formed in the stoichiometric ratio of 1 : 1 and 2 : 1 at pH 5.0 and 37 °C and in the stoichiometric ratio of 1 : 1 only at pH 7.0 and 37 °C. It was also found that Cyt. c could be cleaved by carboplatin at pH 2.5 and 50 °C. The cleaved fragments of Cyt. c were determined by ESI‐MS and MS/MS analysis to be Glu66∼Met80, Ac‐Gly01∼Met65, Glu66∼Glu104, Ac‐Gly01∼Met80 and Ile81∼Glu104. The carboplatin prefers to anchor to Met65 first, then to Met80. To further confirm the binding site of Met, AcMet‐Gly was used as the model molecule to investigate its interaction with carboplatin and its hydrolysis reaction. On the basis of species detected during the reaction monitored by ESI‐MS, a possible pathway of the cleavage reaction was proposed. Copyright © 2005 John Wiley & Sons, Ltd.
Hybrid triple quadrupole‐linear ion trap mass spectrometry in fragmentation mechanism studies: application to structure elucidation of buspirone and one of its metabolites
Authors: Zhang Mei‐Yi , Pace Nadia , Kerns Edward H. , Kleintop Teresa , Kagan Natasha , Sakuma Takeo 
Published: June 2005

AbstractThe use of a hybrid triple quadrupole‐linear ion trap (QqQLIT) mass spectrometer system for a comprehensive study of fragmentation mechanisms is described. The anxiolytic drug, buspirone, was chosen as a model compound for this study. With the advent of a QqQLIT instrument, both the traditional quadrupole and the new linear ion trap scans (LIT) could be performed in a single LC run. In the past, a sample had to be run on two different instruments, namely, a triple quadrupole instrument (QqQ) and a 3D ion trap (3D IT) to obtain similar information. With the new QqQLIT technology, collision‐induced dissociation (CID) occur in a quadrupole collision cell, q2, and fragment ions are trapped and analyzed in Q3 operated in LIT mode. In this work, high‐sensitivity product ion spectra of buspirone were obtained from the one‐stage ‘Enhanced Product Ion’ scan (EPI) with rich product ions and no low mass cut‐off. Furthermore, detailed fragmentation pathways were elucidated by further dissociation of each of the fragment ions in the EPI spectrum using MS3 mode in the same run. The MS3 scan was performed by incorporating CID in q2, and trapping, cooling, isolation, and resonance‐excitation in Q3 when operating in LIT mode. This approach allowed unambiguous assignment of all fragment ions quickly with fewer experiments and easier interpretation than the previous approach. The overall sensitivity for obtaining complete fragment ion data was significantly improved for QqQLIT as compared with that of QqQ and 3D IT mass spectrometers. This is beneficial for structure determination of unknown trace components. The method allowed structure determination of metabolites of buspirone in rat microsomes at 1 µM concentration, which was a 10‐fold lower concentration than was needed for QqQ or 3D IT instruments. The QqQLIT instrument provided a simple, rapid, sensitive and powerful approach for structure elucidation of trace components. Copyright © 2005 John Wiley & Sons, Ltd.
Hydrolysis rates of inorganic polyphosphates in aqueous solution as well as in soils and effects on P availability
Authors: Torres‐Dorante Luis O. , Claassen Norbert , Steingrobe Bernd , Olfs Hans‐Werner 
Published: June 2005

AbstractApplications of polyphosphate‐based fertilizers have been reported to have a positive impact on crop yields as compared to orthophosphate sources. Since plants take up P mainly as orthophosphate, hydrolysis rates of polyphosphates into orthophosphates will determine their fertilizer ability. Laboratory and soil incubation experiments were performed to evaluate hydrolysis rates of pyrophosphate (PP), tripolyphosphate (TP), and trimetaphosphate (TMP) in water as well as in two soils having different P‐fixing capacities. P availability was characterized by measuring the orthophosphate (ortho‐P) and polyphosphate (poly‐P) concentration in soil solution as well as the calcium‐acetate‐lactate (CAL)‐extractable amounts of both forms.In water, PP was completely hydrolyzed within 15 d, whereas TMP was hydrolyzed only to about 30% after 90 d. In the two soils, polyphosphates hydrolyzed during the incubation period increasing ortho‐P concentration in soil solution as well as in CAL extract. At the end of the incubation, no significant differences in ortho‐P concentration in soil solution and CAL extract were found in the sandy soil, whereas in the silty‐loam soil, polyphosphate applications resulted in higher soil‐solution ortho‐P concentration. Although polyphosphate hydrolysis is mainly affected by the soil‐specific enzymatic activity, it seems that polyphosphates and/or hydrolysis products are preferentially adsorbed/precipitated compared to ortho‐P in the silty loam, thereby influencing the P availability from polyphosphate sources.
Spatial variability of sequentially extracted P fractions in a silty loam
Authors: Heilmann Elena , Leinweber Peter , Ollesch Gregor , Meißner Ralph 
Published: June 2005

AbstractKnowledge of the spatial distribution of soil P forms in agricultural fields is important for evaluating the risk of P transfer to waterways. The objective of this study was to characterize the spatial variation of total P (Pt) and sequentially extracted P forms in the Ap horizon of arable soils at the field scale. Soil samples were taken on a regular grid of 50 m × 50 m with 40 sampling points. Chemical analyses included basic soil properties, Pt, sequentially extracted P forms, and acid phosphomonoesterase activity. The spatial variability was analyzed by geostatistics and descriptive statistics. The concentrations of Pt ranged from 521 to 1020 mg kg–1 with lower values observed for Gleysols and Stagnic Phaeozems and higher values for Luvisols and Cambisols. For the sequentially extracted P fractions, the largest coefficients of variation (c.v.) were found for NaHCO3‐Po (41%), NaHCO3‐Pi (36%), NaOH‐Po (34%), and resin‐P (33%). Despite this great spatial variability, no spatial dependence could be proved by geostatistics because the calculated range of P forms (<10 m) was below the smallest sampling distance (50 m). A clear trend of increasing concentrations and proportions of organic NaHCO3‐ and NaOH‐P fractions and phosphomonoesterase activity towards lower slope positions and the discharging brook indicated that Gleysols were a particular source of P losses to waterways in this catchment. It was concluded that these soils require a specific management with reduced P inputs and, perhaps, chemical treatment to fix leachable P.
Proportions of subsurface drainages in large areas—methodological study in the Middle Mulde catchment (Germany)
Authors: Hirt Ulrike , Meyer Burghard C. , Hammann Torsten 
Published: June 2005

AbstractHigh nitrogen (N) input to rivers requires measures for the reduction of diffuse N pollution. Beside the groundwater, artificial subsurface drainage systems are the main pathways of diffuse N input into rivers. Nevertheless, the N discharge via subsurface drainage systems is one of the main missing links for modeling, especially because of the lack of data bases of subsurface drainage areas. We introduce a method to calculate the normally unknown proportions of drained areas in arable lands improving the existing method by Behrendt et al. (2000). The method is applied for the catchment of Middle Mulde river (area: 2,700 km2) in Saxony/Germany. The data records of the mesoscale soil mapping are allocated to the subsurface‐drainage areas digitalized in representative areas using ARC/INFO GIS. In this way, it is possible to establish a differentiated record of the proportion of subsurface‐drainage area of each regional site type. The results were extrapolated to the entire area by transferring the proportions of subsurface‐drainage areas to areas where no information on drainage areas was available. The approach is well‐suited for future model approaches on a regional scale. By creating and integrating new data sets derived from modern GIS operations, the approach reduces the uncertainty of modeling N and water fluxes.
Sorption of HOC in soils with carbonaceous contamination: Influence of organic‐matter composition
Authors: Abelmann Kerstin , Kleineidam Sybille , Knicker Heike , Grathwohl Peter , Kögel‐Knabner Ingrid 
Published: June 2005

AbstractDetailed information about structure and composition of organic sorbents is required to understand their impact on sorption capacity and sorption kinetic of organic pollutants. Therefore, the chemical composition of organic material from 18 geosorbents was investigated by solid‐state 13C nuclear‐magnetic‐resonance (NMR) spectroscopy. Structural parameters such as aromaticity, polarity, and alkyl‐C content were related to the Freundlich sorption exponent (1/n) and the sorption coefficient $ K_{OC}^\circ $. The geosorbents included three natural and four combusted coals (carbonaceous material), three Histosols, five mineral soils from Germany containing inputs of technogenic carbonaceous material, derived from industrial activities, and four non‐contaminated mineral soils from Germany. Equilibrium sorption was measured for five hydrophobic organic compounds and analyzed with the solubility‐normalized Freundlich sorption isotherm. With increasing maturation degree, the proportion of polar constituents decreases from the natural soils to the coals. In contrast to the non‐polluted mineral soils, the soils with technogenic input are characterized by high aromaticity and low polarity. A positive correlation between sorption coefficient $ K_{OC}^\circ $ and aromaticity was found. The Freundlich exponent (1/n) is negatively correlated with the aromaticity, denoting an increase of adsorption processes with increasing aromaticity. Likewise, the contribution of partitioning decreases. This sorption mechanism predominates only if the organic matter in the samples contains a high proportion of polar compounds.
DOC leaching from a coniferous forest floor: modeling a manipulation experiment
Authors: Tipping Edward , Fröberg Mats , Berggren Dan , Mulder Jan , Bergkvist Bo 
Published: June 2005

AbstractThe DyDOC model simulates the C dynamics of forest soils, including the production and transport of dissolved organic matter (DOM), on the basis of soil hydrology, metabolic processes, and sorption reactions. The model recognizes three main pools of soil C: litter, substrate (an intermediate transformation product), and humic substances. The model was used to simulate the behavior of C in the O horizon of soil under a Norway spruce stand at Asa, Sweden, that had been subjected to experimental manipulations (addition and removal) of above‐ground litter inputs and to removal of the Oi and Oe layers. Initially, the model was calibrated using results for the control plots and was able to reproduce the observed total soil C pool and 14C content, DOC flux and DO14C content, and the pool of litter C, together with the assumed content of C in humic substances (20% of the total soil C), and the assumed distribution of DOC between hydrophilic and hydrophobic fractions. The constant describing DOC exchange between micro‐ and macropores was estimated from short‐term variations in DOC concentration. When the calibrated model was used to predict the effects of litter and soil manipulations, it underestimated the additional DOC export (up to 33%) caused by litter addition, and underestimated the 22% reduction in DOC export caused by litter withdrawal. Therefore, an additional metabolic process, the direct conversion of litter to DOC, was added to the model. The addition of this process permitted reasonably accurate simulation of the results of the manipulation experiments, without affecting the goodness‐of‐fit in the model calibration. The results suggest that, under normal conditions, DOC exported from the Asa forest floor is a mixture of compounds derived from soil C pools with a range of residence times. Approximately equal amounts come from the litter pool (turnover time 4.6 yr), the substrate pool (26 yr), and the humic‐substances pool (36 yr).
Chemical characterization and anti‐anaemia activity of fish protein hydrolysate from Saurida elongata
Authors: Dong Yu‐lian , Sheng Guo‐ying , Fu Jia‐mo , Wen Ke‐wei 
Published: June 2005

AbstractA low‐value sea fish Saurida elongata was hydrolyzed using papain. Proximate composition analysis of the fish protein hydrolysate showed that the hydrolysate contained 84.7% crude protein, 7.1% ash and 3.5% fat. The determination of amino acid content by o‐phthaldialdehyde pre‐column derivatization reversed‐phase high‐performance liquid chromatography (RP‐HPLC) showed that the hydrolysate contained 20 different amino acids, and the total percentage of eight essential amino acids was as high as 41.5% of the total amino acids, which meant that the hydrolysate could provide a good nitrogen source for human consumption. Peptides were separated by RP‐HPLC using a C‐18 column into more than 14 fractions. Molecular weight distribution of peptides was determined by size‐exclusion HPLC, which indicated that the size of 74.8% of the peptides ranged from 1.0 to 5.0 kDa. Most importantly, the enzymatic hydrolysate from S elongata was shown to contain significant in vivo anti‐anaemia activity on experimental anaemia models induced by blood loss or cyclophosphamide damage to hematogenic mechanism. To the best of our knowledge, this was the first time that the description of hydrolysis of S elongata and the indication of anti‐anaemia activity in the hydrolysate have been reported. Copyright © 2005 Society of Chemical Industry
PREPARE: seeking systemic solutions for technological crisis management
Authors: Davis Beverly J. 
Published: June 2005

AbstractAmerica's private sector faces an unprecedented challenge in the wake of the 9/11 terrorist attacks. For the first time in the nation's history, its business assets, workers, and critical infrastructures are on the front lines of the battlefield—key targets, and possibly pathways, for future attacks. With terrorism, unconventional declaration of war can be waged, chaos created, and borders crossed by attacking our information highways. Although the catastrophic 9/11 attacks shifted our attention to the United States, the fact remains that Internet attacks against private and public organizations around the world leapt 28% in the 6 months after 9/11. These attacks targeted technology, financial services, and power companies. In order to ‘seek to understand our enemies’, the PREPARE Model of Technological Crisis Management (TCM) along with the application of the Johari Window psychology model will offer business leaders techniques to increase awareness of potential threats to their businesses. The best practice TCM model, a model of continuous process and analysis, takes business cyber‐security to a new level, not only identifying the risks and threats to businesses, but also assessing and creating systemic plans to respond to those risks. Copyright © 2005 John Wiley & Sons, Ltd.
Cultural embeddedness and contextual constraints: knowledge sharing in Chinese and Arab cultures
Authors: Weir David , Hutchings Kate 
Published: June 2005

AbstractIn a recent article Glisby and Holden have noted that the Nonaka and Takeuchi model of knowledge management needs to be used with caution. Its application is not universal because it must be seen primarily as a product of the Japanese cultural context from which it emerged. In the model each of the four modes is interpreted in reference to their embeddedness in Japanese cultural symbols, organizational structures and societal value systems. But we propose that, a fortiori, some aspects of this model do apply to modes of knowledge acquisition and transfer in other cultural contexts. In this paper we review the workings of the model and the four modes with reference to the cultural, organization–structural and value bases of Chinese and Arab societies. We demonstrate that the Nonaka and Takeuchi model maps partially, but differently from both Western and Japanese societies, on to each of these cultural contexts. In these cultures managers and organizational members will share knowledge with those with whom they already have a trustful relationship. This paper explores the implications of the fact that in China and the Arab world the sharing of knowledge cannot be taken for granted outside this context of trustful relationships. Copyright © 2005 John Wiley & Sons, Ltd.
Knowledge management and collaborative model building in the strategy development process
Authors: Adamides Emmanuel , Karacapilidis Nikos 
Published: June 2005

AbstractStrategy formulation is a knowledge‐intensive social process that involves managers with diverse cognitive spheres. The quality of its outcome depends on the efficient and effective construction of shared context that enables issue‐specific knowledge creation through a process of dialectical argumentation. Group model building is an approach that has been proved to facilitate knowledge externalization, recombination and diffusion for sense making and decision making in strategic discourse. In this line, this paper presents a novel approach for enhancing the strategy process on the basis of collaborative model building and selection through structured dialoguing. Contrary to other approaches, group model building and selection by argumentation (G‐MoBSA) adopts a market perspective of the strategic issue resolution space, on which participants propose their models of the issue and its resolution. Models represent the proponents' particular beliefs and views and are subject to consideration and modifications by all group participants, through a process of formal argumentation. Gradually, models that represent the shared context of the organizational and environmental characteristics with respect to the specific strategic issue emerge. The rationale behind our approach, its elements and suitability to strategy formulation, as well as the characteristics and functionality of Knowledge Breeder, an IS framework that supports it, are presented through a sample session of strategy development in a software development company. Copyright © 2005 John Wiley & Sons, Ltd.
International management of taxi cab operations: a case study in Bangkok
Authors: Skok Walter , Vikiniyadhanee Junthima 
Published: June 2005

AbstractTaxi cabs are an important form of transport in major cities in the world, but their management and regulation vary significantly between the developed and developing nations. This paper considers a case study that demonstrates how best practice derived from cities in the West may be transferred to one in the East. The paper begins by reporting on the current environment in Bangkok, where there is no central regulatory body to enforce operating standards. The study involved a stakeholder analysis in order to identify the current problems and understand the context within which taxis operate in a Third World setting. The analysis was based on a high‐level model of taxi cab management derived from similar studies in London, New York and Paris, where strict regulatory procedures are enforced. Finally, a comparison between the developed and developing nations is made in order to make recommendations for possible improvements in regulating and managing taxi cab operations in Bangkok. Copyright © 2005 John Wiley & Sons, Ltd.
Lessons learned by participants of distributed software development
Authors: Komi‐Sirviö Seija , Tihinen Maarit 
Published: June 2005

AbstractThe maturation of the technical infrastructure has enabled the emergence and growth of distributed software development. This has created tempting opportunities for companies to distribute their software development, for example, to economically favourable countries so as to gain needed expertise or to get closer to customers. Nonetheless, such distribution potentially creates problems that need to be understood and addressed in order to make possible the gains offered. To clarify and understand the most difficult problems and their nature, a survey of individuals engaged in distributed software development was conducted. The purpose of this survey was to gather and share lessons learned in order to better understand the nature of the software development process when operating in a distributed software development environment and the problems that may be associated with such distributed processes. Through a clear appreciation of the risks associated with distributed development it becomes possible to develop approaches for the mitigation of these risks. This paper presents the results of the survey, focusing on the most serious problems raised by the respondents. Some practical guidelines that have been developed by industry to overcome these problems are also briefly summarized. Copyright © 2005 John Wiley & Sons, Ltd.
Facilitating knowledge management through market mechanism
Authors: Desouza Kevin C. , Awazu Yukika , Yamakawa Shigetaka , Umezawa Masashi 
Published: June 2005

AbstractWhile knowledge markets are in existence and have been shown to be valuable, researchers have yet to systematically investigate them. In this paper, we take the first steps towards an investigation into the mechanisms of knowledge markets. Specifically, we employ a mathematical orientation to demonstrate the pivotal role played by pricing schemes in knowledge management agendas. Our work contributes to the field of knowledge management by providing mathematical proofs rather than anecdotal evidence regarding the significance of pricing knowledge in organizations. Copyright © 2005 John Wiley & Sons, Ltd.
Fragmentation of Ziegler‐Natta Catalyst Particles During Propylene Polymerization
Authors: Abboud Mohammed , Denifl Peter , Reichert Karl‐Heinz 
Published: June 2005

AbstractSummary: Analyzing polymer particles by microscopy technique at different polymerization times provided information regarding the catalyst support break‐up rate and degree of fragmentation during polymerization. Polymer samples were prepared at different polymerization times and melted under a video microscope to track the progress of fragmentation. Studies focused on effect of the catalyst support on the process and degree of catalyst fragmentation. Fragmentation behaviors of both a catalyst without an external support and a silica supported Ziegler‐Natta catalyst were compared. Fragmentation of catalyst was observed to occur in the whole catalyst matrix at the very beginning of polymerization. In the case of the catalyst without an external support, fragmentation was faster and more uniform than that of the silica supported catalyst. Results corresponded to the activity distribution of single catalyst particles as determined by video microscopy. The catalyst without an external support having particles of similar activities showed similar degrees of fragmentation. Conversely, silica supported catalyst having particles of different growth behavior produced particles having different degrees of fragmentation. The rate of increase in the number of catalyst fragments and their surface area with time during polymerization was investigated. Results correlated the catalyst activation period during the initial stage of polymerization to catalyst fragmentation.Poly(propylene) particles produced with silica supported (upper image) and non‐supported (lower image) Ziegler‐Natta catalysts.magnified imagePoly(propylene) particles produced with silica supported (upper image) and non‐supported (lower image) Ziegler‐Natta catalysts.