bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chromatographic enantioseparation of amino acids using a new chiral stationary phase based on a macrocyclic glycopeptide antibiotic
Authors: Petrusevska Katerina , Kuznetsov Mikhail A. , Gedicke Knut , Meshko Vera , Staroverov Sergey M. , Seidel‐Morgenstern Andreas 
Published: July 2006

AbstractThe separation of the enantiomers of several α‐amino acids was studied on a new chiral stationary phase (CSP) which is based on the macrocyclic glycopeptide antibiotic eremomycin attached to silica particles. Retention and separation factors were determined under analytical conditions at ambient temperature for different mobile phase compositions. In order to evaluate the potential with respect to preparative separations the adsorption isotherms of D‐ and L‐methionine were determined for one mobile phase composition applying the elution by characteristic point method. The isotherms were validated by comparing experimentally determined elution profiles with predictions based on the equilibrium dispersive model. Finally, the performance of the eremomycin CSP was compared with a commercially available CSP based on the macrocyclic antibiotic teicoplanin. After determining the isotherms of D‐ and L‐methionine also for the teicoplanin phase, the equilibrium dispersive model was used for both CSP to identify optimal operating conditions. For the separation and conditions considered the new eremomycin CSP revealed a better performance compared to the teicoplanin CSP.
Hydrological changes and land degradation in the southern and eastern Tarim basin, Xinjiang, China
Authors: Yang X. , Liu Z. , Zhang F. , White P. D. , Wang X. 
Published: July 2006

AbstractUsing the combined methods of digital image processing of remote sensing data, a Geographical Information System (GIS) and analysis of historical books and maps, this paper aims to contribute to a better understanding of the processes and mechanisms of land‐use and land‐cover changes and hydrological variations during the last 2000 years in a hyper‐arid environment. The southern and eastern Taklamakan Desert, one of the driest and ecologically most sensitive regions in China and characterized by a long history of human settlements, was chosen as the study area. A hydrological connection between the Keriya and Niya rivers in former times was recognized for the first time using satellite imagery. After transferring the notes and maps of historical times into a simplified modern map, it shows that the Lop Nuer decreased in size from a large lake in the Han Dynasty (206BCtoAD220) to a much smaller one in the Qing Dynasty (AD1644–1911). Areas settled in former times differ morphologically from the dune landscape in satellite imagery because of flat relief along dried river courses. A review of archaeological literature reinforces the fact that in the lower reaches of the Keriya and Niya rivers, in the interior of the Taklamakan Desert, irrigated agriculture was widely practised fromca. 200BCtoca.AD500. A possible climatic change toward drier conditions atca.AD500 is suggested as the cause of the abandonment of the cities in the desert and for the initial drying of the formerly large Lop Nuer Lake. Copyright © 2006 John Wiley & Sons, Ltd.
Dewatering of the Far West Rand dolomitic area by gold mining activities and subsequent ground instability
Authors: van Niekerk H. J. , van der Walt I. J. 
Published: July 2006

AbstractIn the 1960s, the Malmani dolomite landscape of the Transvaal Sequence on the Far West Rand experienced ground subsidence in the form of sudden catastrophic sinkhole formations and extensive development of dolines by gradual subsidence. The management of the gold mines had decided to dewater some of the dolomitic compartments to allow their workers to extract the gold‐bearing ore of the underlying Witwatersrand Supergroup economically and safely.Several of the gold mines on the Far West Rand have now reached the end of their life span and are due to be decommissioned. Dewatering will be discontinued. Some of the dykes that form the boundaries of the individual dolomitic compartments have been breached by mining activities so that flooding of one compartment will eventually impact on the other compartments. The eventual static level of the water‐table in this new ‘super‐compartment’, as well as the points of decant of the dolomitic water, are uncertain. Flooding of the ‘super‐compartment’ will cause the original dolomitic eyes feeding the Wonderfontein Spruit to start flowing again, which will impact on groundwater quality and ground instability. Of particular concern is the occurrence of millions of tonnes of mine tailings within the catchment area.The most important problem in the catchment area is that the sedimentary phase of the Wonderfontein Spruit and its impoundments is continually being enriched with heavy metals and radio nuclides originating at the mining works. These could be remobilized and released into the downstream water, causing deterioration of water quality for downstream users. Copyright © 2006 John Wiley & Sons, Ltd.
Some multidisciplinary techniques used in MIC studies
Authors: Wang W. , Wang J. , Xu H. , Li X. 
Published: July 2006

AbstractThis paper presents a review of the application of microbiological methods, chemical analysis and surface analysis techniques in studying the microbially influenced corrosion (MIC) process of metals and their alloys. As a multidisciplinary research, some techniques used to study biofilm‐related problems are also discussed in this paper, as potential tools in this field.
Structure and Thermal Analyses of MAA‐Grafted Silk Fiber Using DSC and 13C Solid‐State NMR
Authors: Kameda Tsunenori , Tsukada Masuhiro 
Published: July 2006

AbstractSummary: By using DSC, 13C CP/MAS NMR and SEM, we studied the physical properties and chemical structure of silk fibers grafted with methacrylamide (MAA). At a given MAA concentration, the inverse of fiber weight gain linearly increased with increasing square root of the initiator concentration, and at a given initiator concentration the fiber weight gain increased with increasing MAA concentration. 13C CP/MAS NMR demonstrated that the primary and secondary structure remained unchanged, regardless of MAA grafting, implying the poor compatibility and the lack of new additional hydrogen bonding between the silk fiber and the MAA graft polymer. The degree of grafting in MAA‐grafted silk fiber (the accurate amount of actually loaded MAA polymer within the fiber matrix) can be evaluated from determination of the ratio of heat capacities calculated from two individual endothermic DSC peaks of silk fibroin and MAA polymer. The major endothermic peaks attributable to thermal degradation of the silk fiber and MAA graft polymer shifted to a higher temperature with increasing fiber weight gain by grafting. These findings are useful for the industrial production of grafted silk fiber with higher thermal stability.CP/MAS spectra for poly(MAA) grafted silk and control silk fiber.magnified imageCP/MAS spectra for poly(MAA) grafted silk and control silk fiber.
Interactive reference direction approach using implicit parametrization for nonlinear multiobjective optimization
Authors: Miettinen Kaisa , Kirilov Leoneed 
Published: July 2006

AbstractA method for solving nonlinear multiobjective optimization problems is presented. In this interactive method, the dialog with a decision maker takes place in terms of desirable aspiration levels forming a reference point in the objective function space. In the computation phase, a lexicographic subproblem is used to generate a desired number of nondominated solutions. Thus, the decision maker can direct the interactive solution process both by specifying reference points and by setting the number of new solutions to be generated at each iteration. The proposed method gives the decision maker a possibility to investigate any part of the whole nondominated set according to his/her preferences and emphasizes learning possibilities. The functioning of the method is illustrated with a numerical example. Copyright © 2006 John Wiley & Sons, Ltd.
A formulation of portfolio selection problem with multiple criteria
Authors: Polyashuk Marina V. 
Published: July 2006

AbstractPortfolio‐type problems arise in many decision‐making situations. In this paper, we consider these problems in the context of multiple criteria model that takes into account two types of criteria, which are used in decision maker's preferences: criteria of the first type are used to characterize both the entire portfolio and its individual elements, whereas criteria of the second type are solely used to evaluate the portfolio as a whole but not its elements. When formulating our multiple criteria model, we assume that criteria of the first type are quantitative and that they represent a higher priority for the decision maker compared to criteria of the second type. While we acknowledge the existence of other approaches, in this paper we focus on those portfolio selection problems that match the above structure of the criteria set. After formulating the portfolio selection problem, we offer a two‐phase portfolio selection procedure that allows to choose an optimal portfolio by operating in two separate criteria spaces. Copyright © 2006 John Wiley & Sons, Ltd.
Epigenetic regulation of the expression of the novel stem cell marker CDCP1 in cancer cells
Authors: Ikeda J‐i , Morii E , Kimura H , Tomita Y , Takakuwa T , Hasegawa J‐i , Kim Y‐K , Miyoshi Y , Noguchi S , Nishida T , Aozasa K 
Published: July 2006

AbstractCDCP1 is a novel stem cell marker that is expressed in several types of cancer. The mechanisms by which CDCP1 expression is regulated, and the clinical implications of this marker, have not been clarified. In this report, we examine the epigenetic regulation of CDCP1 expression in cell lines and clinical samples from patients with breast cancer. Many CpG sequences were localized around the transcription initiation site of CDCP1. These CpG motifs were found to be poorly methylated in cell lines with high levels of CDCP1 expression and heavily methylated in cell lines with low levels of CDCP1 expression. The in vitro methylation of CpG sites decreased CDCP1 promoter activity, and the addition of a demethylating reagent restored activity. In 25 breast cancer samples, an inverse correlation was noted between the CDCP1 expression level and the proportion of methylated to non‐methylated CpG sites. Tumours with high‐level CDCP1 expression showed higher levels of proliferation, as revealed by immunohistochemical detection of the MIB‐1 antigen, than tumours with low‐level CDCP1 expression. These findings indicate that the expression of CDCP1 is regulated by methylation of its promoter region in tumours. CDCP1 expression may prove to be useful in the further characterization of cancers. Copyright © 2006 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Primary testicular diffuse large B‐cell lymphomas have activated B‐cell‐like subtype characteristics
Authors: Booman M , Douwes J , Glas AM , de Jong D , Schuuring E , Kluin PM 
Published: July 2006

AbstractDiffuse large B‐cell lymphomas (DLBCLs) constitute a heterogeneous group of lymphomas in which germinal centre B‐cell‐like and activated B‐cell‐like subtypes can be discerned based on pathology, clinical presentation, and gene expression patterns. Testicular DLBCLs form an immune‐privileged site‐related subgroup of DLBCLs with an unfavourable prognosis. In the present study, cDNA microarray analysis, immunohistochemistry for CD10, Bcl6 and MUM1, and somatic hypermutation analysis of the immunoglobulin heavy chain gene rearrangements were used to determine the subtype of primary testicular DLBCL. Immunohistochemistry revealed 14/22 testicular DLBCLs with an activated B‐cell‐like immunophenotype and 8/22 with an ambiguous immunophenotype co‐expressing CD10 and high levels of MUM1. cDNA microarray analysis of these 22 and four additional cases showed a uniform activated B‐cell‐like gene expression pattern for both immunophenotypes. Somatic hypermutation analysis of immunoglobulin heavy chain genes showed a very high mutation load in seven cases tested, but intraclonal heterogeneity was found at low level in only one of these cases. It is concluded that primary testicular DLBCLs have uniform activated B‐cell‐like subtype characteristics despite a number of cases showing an ambiguous immunophenotype. Copyright © 2006 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Quality aspects of prenatal cytogenetic diagnosis: determining the effect of various factors involved in handling amniotic fluid and chorionic villus material for cytogenetic diagnosis
Authors: Sikkema‐Raddatz Birgit , Suijkerbuijk Ron , Bouman Katelijne , de Jong Bauke , Buys Charles H.C.M. , te Meerman Gerard J. 
Published: July 2006

AbstractObjectivesTo investigate the effect of factors involved in cell culturing and slide preparation of amniotic fluid (AF) and chorionic villus biopsies (CVB) for prenatal cytogenetic diagnosis.MethodsThe effect on the outcome of our standard AF cell culture procedure of volume and appearance of the submitted AF specimen, gynaecologist performing the amniocentesis, week of gestation in which the specimen was taken and culture medium was retrospectively investigated. In a prospective study controlled experimental variation was introduced in composition of fixative, relative humidity, temperature and airflow during slide preparation from primary CVB and AF in situ cultures. For evaluation, analysis of regression or variance was used.ResultsProvided that at least 0.8 mL AF per culture dish was admitted, none of the investigated factors appeared as critical resulting in unacceptable variation in outcome. Variation in appearance of the AF had a relatively major impact: bloody or brown AF resulted in a 3 days longer culture time.To a limited degree, metaphase quality of AF and CVB cells was affected by composition of fixative, relative humidity, ambient temperature and airflow during slide preparation.ConclusionCurrent prenatal cytogenetic practice as described here appears in general to be robust and reliable. The investigated conditions are not critical within the investigated range. Expensive measures for fine control of these conditions are, therefore, not required. Copyright © 2006 John Wiley & Sons, Ltd.
Prenatal diagnosis of β‐thalassemia in Southern Punjab, Pakistan
Authors: Baig Shahid Mahmood , Azhar Ayesha , Hassan Hammad , Baig Jamshaid Mahmood , Aslam Muhammad , Ud Din Mohammad Amin , Qureshi Javed Anver , Zaman Tariq 
Published: July 2006

AbstractPakistan has a large population of more than 150 million people with an overall carrier frequency of approximately 5.6% for β‐thalassemia. Punjab is the largest province of the country having more than 50% of the population. The state of β‐thalassemia is alarming as consanguinity is very high (>81%) and the literacy rate is low in South Punjab. A thalassemia prevention program is the need of the hour in this part of Pakistan. In this study, we initiated awareness, screening, and characterization of the mutations causing β‐thalassemia as well as a genetic counseling program mainly in the districts of Faisalabad and D.G. Khan to establish prenatal diagnosis, a facility previously unavailable in this region for disease prevention. A total of 248 unrelated transfusion‐dependent children and the available members of their families were screened to characterize the mutations and identify the carriers. Genetic counseling was provided to these families and prenatal diagnosis offered. In the samples analyzed, 11 β‐thalassemia mutations and three hemoglobin variants were detected mainly by using the Monoplex and Multiplex ARMS‐PCR. First‐trimester prenatal diagnosis was carried out through chorionic villus sampling (CVS) in seven pregnancies at risk. As a result of our campaign, 145 carrier couples planning to have more children gave their consent to have retrospective prenatal diagnosis in every pregnancy in future. A cooperative trend and a positive attitude toward the prevention of β‐thalassemia were noticed in the families with affected children and in the general population. Copyright © 2006 John Wiley & Sons, Ltd.
Adverse events among nursing home residents with Alzheimer's disease and psychosis
Authors: Oliveria Susan A. , Liperoti Rosa , L'Italien Gilbert , Pugner Klaus , Safferman Allan , Carson William , Lapane Kate 
Published: July 2006

AbstractPurposeThe objective of this study was to quantify rates of adverse events in a high‐risk multi‐morbid population of institutionalized patients with Alzheimer's disease (AD).MethodsWe conducted a retrospective cohort study among nursing home residents diagnosed with AD and psychosis during January 1998 to October 1999. Using the Medicare Minimum Data Set (MDS) and Medicare inpatient claims (ICD‐9 codes), 7728 nursing home residents aged 55–95 years with AD and psychosis were identified for study. Potential adverse events of interest were identified from the MDS and Medicare inpatient claims (ICD‐9 codes). We estimated the incidence rate (IR) and 95% confidence interval (CI) for each adverse event during a 2‐year follow‐up period.ResultsOf the 7728 residents studied, nearly 30% were considered ‘dependent’ by the activities of daily living (ADL) score and approximately 15% exhibited severe cognitive impairment at baseline. At least 90% had comorbid psychiatric disorders. The most common adverse event was accidental injury, occurring at a rate of 97.7 per 100 person‐years (95%CI = 94.7–100.7). Other common adverse events were death (IR = 44.6/100 person‐years; 95%CI = 42.9–46.4), infection (IR = 41.8/100 person‐years; 95%CI = 39.7–43.8), pain (IR = 43.5/100 person‐years; 95%CI = 41.2–45.9), anorexia (41.3/100 person‐years; 95%CI = 39.1–43.6), and weight change (IR = 40.2/100 person‐years; 95%CI = 38.7–41.7).ConclusionsThis information on the occurrence of adverse outcomes among nursing home patients with AD and psychosis provides useful context for any safety event observed among patients treated for psychosis. Copyright © 2006 John Wiley & Sons, Ltd.
Polymer layered silicate/carbon nanotube nanocomposites: The catalyzed polymerization approach
Authors: Peeterbroeck S. , Lepoittevin B. , Pollet E. , Benali S. , Broekaert C. , Alexandre M. , Bonduel D. , Viville P. , Lazzaroni R. , Dubois P. 
Published: July 2006

AbstractA two‐step route to polymer/layered silicate nanocomposites characterized by a large extent of nanoplatelet delamination is presented. It consists first in the preparation of poly(ε‐caprolactone) (PCL)‐grafted clay masterbatches (containing ∼30 wt% clay) by in situ intercalative polymerization of ε‐caprolactone (CL) in bulk. The CL polymerization is promoted at the surface of organomodified clays bearing targeted amounts of alcohol functionalities used as initiating species. The influence of alcohol concentration on clay platelets coverage by PCL has been studied by atomic force microscopy. In a second step, these masterbatches are readily dispersed in commercial matrices (PCL, PVC, chlorinated polyethylene) via rather conventional melt blending. The morphology of the resulting nanocomposites has been characterized as well as their thermal and mechanical properties. Interestingly enough, this “masterbatch” process can be extrapolated to another type of nanocomposites, i.e., polyolefin carbon nanotube nanocomposites. Accordingly, homogeneous surface coating of multi‐walled carbon nanotubes (MWNTs) is first achieved by in situ polymerization of ethylene as catalyzed directly from the nanotube previously surface‐treated by a highly active metallocene‐based complex. This polyolefin coating allows for the destructuration of the native nanotube bundles leading upon further melt blending with, e.g., ethylene‐co‐vinyl acetate copolymers (EVA), to high performance nanocomposites with finely dispersed MWNTs. POLYM. ENG. SCI. 46:1022–1030, 2006. © 2006 Society of Plastics Engineers
Effect of crystallization on intercalation of clay‐polyolefin nanocomposites and their performance
Authors: Ton‐That M.‐T. , Leelapornpisit W. , Utracki L.A. , Perrin‐Sarazin F. , Denault J. , Cole K.C. , Bureau M.N. 
Published: July 2006

AbstractClay‐polypropylene (PP) nanocomposites (NCs) were prepared by melt processing. Two types of PP with different levels of crystallinity were used. Mixtures of the two PPs were made at different ratios that generate a varying degree of crystallinity for the final NC samples. The level of micro‐ and nanodispersion of the organoclays and the microstructure of the resulting NCs were characterized by means of various techniques, including X‐ray diffraction analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and differential scanning calorimetry (DSC). The results have demonstrated the impact of crystallization on the level of clay intercalation. The mechanical performance of the nanocomposites was also evaluated, but a direct relationship between intercalation and mechanical properties cannot be established because of the difference in the mechanical properties of the two PP matrices. POLYM. ENG. SCI. 46:1085–1093, 2006. © 2006 Society of Plastics Engineers
Epoxy nanocomposites curing by microwaves
Authors: Uyanık Nurseli , Erdem A. Rıza , Can M. Fatih , Çelik Mehmet Sabri 
Published: July 2006

AbstractIn this work, chemically modified sodium montmorillonite and epoxy monomer were used to prepare nanocomposites in two consecutive stages. In the first stage, dodecylamine, octadecylamine, hexadecylamine, and hexadecyltrimethyl ammonium bromide were used to prepare various organophilic clays. In the second stage, the bisphenol‐A based epoxy monomer and predetermined amounts of organoclay were mixed together and then cured by an aliphatic polyamine for 20 min under microwave at 400 W. Furthermore, α‐ω diacrylate poly(dimethylsiloxane) was added to the mixture before the curing process to modify the toughness of the samples. The mixture was poured into the poly(tetrafluoroethylene) mold; the epoxy resin/curing agent ratio was maintained as 2/1. The clear films formed after microwave irradiation were removed from the mold, cooled, and then stored in a cool and dry medium until characterization. The samples were analyzed by wide angle X‐ray diffraction, differential scanning calorimetry, and mechanical tests. Surfaces of the cold fractured samples were also observed under the scanning electron microscope. The results revealed that microwave curing of the samples of 5% organoclay and 5% siloxane showed improvement in mechanical properties. POLYM. ENG. SCI. 46:1104–1110, 2006. © 2006 Society of Plastics Engineers
Morphology and properties of organoclay modified polycarbonate/poly(methyl methacrylate) blend
Authors: Ray S. Sinha , Bousmina M. , Maazouz A. 
Published: July 2006

AbstractVirgin and organoclay modified polycarbonate (PC)/poly(methyl methacrylate) (PMMA) (30/70 w/w) blends were prepared by melt‐mixing of PC, PMMA, and organically modified montmorillonite (OMMT). The morphology of OMMT modified PC/PMMA blend with two different weight percents of OMMT was studied using scanning electron microscopy, transmission electron microscopy (TEM), and X‐ray diffraction (XRD). The size of the phase‐separated domains decreased dramatically with increasing the content of OMMT. XRD patterns and TEM observations revealed that silicate layers were intercalated and nicely dispersed in the blend matrix. Differential scanning calorimetry analyses showed efficient mixing of two immiscible polymers in the presence of OMMT. The blend nanocomposites showed greatly improved mechanical properties when compared with the same blend sample without OMMT. Finally, the opaque immiscible PC/PMMA blend became translucent after modification with OMMT addition. POLYM. ENG. SCI., 46:1121–1129, 2006. © 2006 Society of Plastics Engineers