bluuebunny/crossref_metadata_2025_split huggingface dataset:
Syntheses and micellar properties of well‐defined amphiphilic AB2and A2B Y‐shaped miktoarm star copolymers of ε‐caprolactone and 2‐(dimethylamino)ethyl methacrylate
Authors: Liu Hao , Xu Jian , Jiang Jiali , Yin Jun , Narain Ravin , Cai Yuanli , Liu Shiyong 
Published: March 2007

AbstractWell‐defined amphiphilic PCL‐b‐(PDMA)2and (PCL)2‐b‐PDMA Y‐shaped miktoarm star copolymers and PCL‐b‐PDMA linear diblock copolymer were synthesized via a combination of ring‐opening polymerization (ROP) and atom transfer radical polymerization (ATRP), where PCL is poly (ε‐caprolactone) and PDMA is poly(2‐(dimethylamino)ethyl methacrylate). All of these three types of copolymers have comparable PCL contents and overall molecular weights. The PCL block is hydrophobic while the PDMA block is hydrophilic, and they behave like polymeric surfactants and self‐assemble into PCL‐core micelles in aqueous media. The chain architectural effects on the micellization properties, including the aggregation number, size, polydispersity, and micelle densities of (PCL29)2‐b‐PDMA45, PCL61‐b‐(PDMA24)2, and PCL56‐b‐PDMA49in dilute aqueous solution, were then explored by dynamic and static laser light scattering (LLS). The intensity–average hydrodynamic radius, 〈Rh〉, the aggregation number per micelle,Nagg, and the core radius,Rcore, of the PCL‐core micelles all increased in the order PCL61‐b‐(PDMA24)2< (PCL29)2‐b‐PDMA45< PCL56‐b‐PDMA49. The surface area occupied per soluble PDMA block at the core/corona interface increased in the order PCL61‐b‐(PDMA24)2< PCL56‐b‐PDMA49< (PCL29)2‐b‐PDMA45. PCL61‐b‐(PDMA24)2micelles had the largest overall micelle density, possibly because of that the presence of two soluble PDMA arms at the junction point favors the bending of the core–corona interface and thus the formation of densely‐packed core‐shell nanostructures. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1446–1462, 2007
Semicontinuous heterophase polymerization under monomer starved conditions to prepare nanoparticles with narrow size distribution
Authors: Ledezma Raquel , Esther Treviño M. , Elizalde Luis E. , Pérez‐Carrillo Lourdes A. , Mendizábal Eduardo , Puig Jorge E. , López Raúl G. 
Published: March 2007

AbstractThe semicontinuous polymerization of methyl methacrylate (MMA) in heterogeneous medium under monomer‐starved conditions is reported here. The effect of monomer addition rate on kinetics, particle size, particle number, and PMMA average molar masses are reported. This process permits the synthesis of high‐solid content latexes containing nano‐sized particles (<40 nm) with narrow particle size distributions [(Dw/Dn) < 1.1]. Moreover, the molar masses (Mn ≈ 0.3–1.2 × 106 g/mol) are much lower than those expected by chain transfer to monomer, which is the typical termination mechanism in 0–1 emulsion and microemulsion reactions. Both particle size and average molar masses decrease as the rate of monomer addition is diminished. Possible explanations for this process are provided. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1463–1473, 2007
Mycoherbicide formulation and the potential for bracken control
Authors: Womack Jonathan G. , Burge Michael N. 
Published: March 2007

AbstractThe imperfect fungusAscochtya pteridis, causal agent of curl‐tip disease, is considered as the potential active ingredient of a mycoherbicide for the control of bracken (Pteridium aquilinum(L.) Kühn) Results of experimental attempts to improve pathogenicity by the addition to the spore inoculum of one or more adjuvants are reviewed. The importance of protecting spores and germ tubes from desiccation in the pre‐penetration phase is emphasised and results of experiments demonstrating the potential for water retention by invert (water‐in‐oil) emulsions discussed. Provisional results of field trials using an invert emulsion of water in soybean oil are summarised. Infection was achieved, but it is though that the low level of mycoherbicidal activity was due to application when the host was beyond its most susceptible stage.
Recent advances in the biological control of fusarium wilts
Authors: Alabouvette Claude , Lemanceau Philippe , Steinberg Christian 
Published: March 2007

AbstractStudies of soils suppressive to fusarium wilts have indicated that the phenomenon is fundamentally microbiological in nature, resulting from complex microbial interactions between the pathogen and all, or a part of, the saprophytic microflora.Many groups of micro‐organisms have been proposed as having a role in this process. The most consistent results show that non‐pathogenic Fusarium oxysporum and fluorescent pseudomonads are the main agents for biological control. Each group has been effective in reducing the severity of fusarium diseases in several crops under experimental conditions. All the problems associated with application of antagonists have not yet been solved, but special situations exist where biological control could be applied soon.In Europe, the present development of soil‐less systems to grow tomatoes, cucumbers, carnations and a few other species of flowers and vegetables in greenhouses, offers a unique opportunity to use antagonists. A strain of non‐pathogenic Fusarium isolated from soil from Chǎteaurenard can be established in the soil‐less substrates, or in the potting mixtures, before transplanting the plants and in these conditions can prevent colonization of the substrates by the pathogens. It gave good control of fusarium wilts of tomatoes, carnations and cyclamens, and of crown and root rot of tomatoes due to F. oxysporum f.sp.radicis lycopersici. This non‐pathogenic strain, produced by liquid fermentation and mixed with talc, is easy to introduce into soil‐less substrates after having been suspended in water or in liquid fertilizer.Experiments have been under way in commercial greenhouses for several years, but it will be necessary to wait at least two more years to complete all the tests required for the registration of the product as a biopesticide.Similar experiments have been conducted with a strain of fluorescent pseudo‐monad also isolated from the soil of Chǎteaurenard, which shows poor antagonistic effect when applied alone but consistently improves disease control when applied in combination with the non‐pathogenic Fusarium. In fact, application of both antagonists together always gave total control of the diseases, the yield in the treated plots being equal to that in the healthy control. These experiments show that combining antagonists can improve the consistency of biological control.
A Fraction of Acorus calamus L. extract devoid of β‐asarone Enhances adipocyte differentiation in 3T3‐L1 cells
Authors: Wu Hao‐shu , Li Ying‐yin , Weng Lin‐jia , Zhou Chang‐xin , He Qiao‐jun , Lou Yi‐jia 
Published: March 2007

AbstractThe effects of fractions partitioned from the ethanol extract of Acorus calamus L. (AC) on adipocyte differentiation were investigated using cultured mouse 3T3‐L1 preadipocytes. The degree of differentiation was evaluated by measuring the cellular triglycerides and protein expression of the glucose transporter GLUT4 in 3T3‐L1 cells. The ethyl acetate fraction of the AC extract (ACE) was found to enhance adipocyte differentiation as did rosiglitazone. The results of further fractionation of ACE indicated that the active fraction does not consist of β‐asarone, which is a toxic component of this plant. This finding suggests that ACE has potential insulin‐sensitizing activity like rosiglitazone, and may improve type 2 diabetes. Copyright © 2007 John Wiley & Sons, Ltd.
Antipromastigote activity of the malabaricones of Myristica malabarica (rampatri)
Authors: Sen Rupashree , Bauri Ajay Kumar , Chattopadhyay Subrata , Chatterjee Mitali 
Published: March 2007

AbstractA major problem in the management of visceral leishmaniasis, especially in the Indian subcontinent, is the growing unresponsiveness to conventional antimonial therapy, indicating the urgent need to identify new antileishmanial compounds. This study was undertaken to evaluate the antileishmanial activity of the fruit rind of Myristica malabarica that is used as a spice and is also credited with medicinal properties. The antipromastigote activity of different extracts/fractions of M. malabarica and its constituent diarylnonanoids were evaluated in Leishmania donovani promastigotes (MHOM/IN/83/AG83) using the MTS‐PMS assay. Preliminary screening of the ether extract (R1) with its crude methanol fraction (R2) and two fractions (R3 and R4) revealed that R2 had potent leishmanicidal activity (IC50 31.0 µg/mL), whereas R3 and R4 showed poor activity. Fractionation of R2 yielded four diarylnonanoids (malabaricones A–D, designated as Mal A, Mal B, Mal C and Mal D, respectively). The IC50 values of Mal A–D were 16, 22, 27 and >50 µg/mL, respectively. Taken together, the data suggest that the methanol extract of M. malabarica, especially its constituent compounds, Mal A and Mal B, have promising antileishmanial activity meriting further investigations regarding the underlying molecular mechanism(s) of action with a view towards future drug development. Copyright © 2007 John Wiley & Sons, Ltd.
Examination of the distribution of the bioreductive drug AQ4N and its active metabolite AQ4 in solid tumours by imaging matrix‐assisted laser desorption/ionisation mass spectrometry
Authors: Atkinson Sally J. , Loadman Paul M. , Sutton Chris , Patterson Laurence H. , Clench Malcolm R. 
Published: March 2007

AbstractAQ4N (banoxatrone) (1,4‐bis‐{[2‐(dimethylamino‐N‐oxide)ethyl]amino}‐5,8‐dihydroxyanthracene‐9,10‐dione) is an example of a bioreductive prodrug in clinical development. In hypoxic cells AQ4N is reduced to the topoisomerase II inhibitor AQ4 (1,4‐bis‐ {[2‐(dimethylamino)ethyl]amino}‐5,8‐dihydroxyanthracene‐9,10‐dione). By inhibition of topoisomerase II within these hypoxic areas, AQ4N has been shown to sensitise tumours to existing chemo‐ and radiotherapy treatments. In this study the distribution of AQ4N and AQ4 in treated H460 human tumour xenografts has been examined by imaging matrix‐assisted laser desorption/ionisation mass spectrometry. Images of the distribution of AQ4N and AQ4 have been produced that show little overlap. The distribution of ATP in the tumour xenografts was also studied as an endogenous marker of regions of hypoxia since concentrations of ATP are known to be decreased in these regions. The distribution of ATP was similar to that of AQ4N, i.e. in regions of abundant ATP there was no evidence of conversion of AQ4N into AQ4. This indicates that the cytotoxic metabolite AQ4 is confined to hypoxic regions of the tumour as intended. Copyright © 2007 John Wiley & Sons, Ltd.
Simultaneous determination of first‐line anti‐tuberculosis drugs and their major metabolic ratios by liquid chromatography/tandem mass spectrometry
Authors: Song Sang Hoon , Jun Sun Hee , Park Kyoung Un , Yoon Yeomin , Lee Jae Ho , Kim Jin Q , Song Junghan 
Published: March 2007

AbstractMonitoring of anti‐tuberculosis drug concentrations and dose adjustment can be helpful in cases that show poor response to treatment. Here, we describe a method that can rapidly and simultaneously measure the blood concentrations of four anti‐tuberculosis drugs (isoniazid, rifampicin, pyrazinamide, and ethambutol) and two major metabolic ratios (acetylisoniazid/isoniazid and 25‐desacetylrifampicin/rifampicin) using high‐performance liquid chromatography/tandem mass spectrometry (HPLC/MS/MS). A C18 reversed‐phase column and gradients of methanol in 0.3% formic acid and water were used for HPLC separation. The drug concentrations were determined by multiple reaction monitoring in positive ion mode and the assay performance was evaluated. We determined peak concentration ranges for each drug and acetylisoniazid/isoniazid and 25‐desacetylrifampicin/rifampicin ratios by analyzing 2‐h post‐dose samples in patients treated with standard dosing as a first‐line treatment. The preparation of 20 samples including two steps of deproteinization with 50% and 100% methanol was performed within 20 min and chromatographic separation was achieved within 4 min/sample. Interassay calibration variability data obtained over concentrations of 0–8 µg/mL for isoniazid and ethambutol and 0–80 µg/mL for rifampicin and pyrazinamide showed a linear and reproducible curve. Within‐run and between‐run imprecision (CVs) were 1.9–5.5% and 3.5–10.5% and the lower limits of detection and quantification were 0.01–0.5 µg/mL and 0.05–1.0 µg/mL, respectively. The isoniazid concentration was found to be inversely correlated to the acetylisoniazid/isoniazid ratio (R = −0.739, P < 0.001). The devised method allows for the simple, rapid, sensitive and reproducible quantification of isoniazid, rifampicin, pyrazinamide, ethambutol and their two metabolic ratios and should be helpful for therapeutic drug monitoring in tuberculosis patients. Copyright © 2007 John Wiley & Sons, Ltd.
Automated time series forecasting for biosurveillance
Authors: Burkom Howard S. , Murphy Sean Patrick , Shmueli Galit 
Published: March 2007

AbstractFor robust detection performance, traditional control chart monitoring for biosurveillance is based on input data free of trends, day‐of‐week effects, and other systematic behaviour. Time series forecasting methods may be used to remove this behaviour by subtracting forecasts from observations to form residuals for algorithmic input. We describe three forecast methods and compare their predictive accuracy on each of 16 authentic syndromic data streams. The methods are (1) a non‐adaptive regression model using a long historical baseline, (2) an adaptive regression model with a shorter, sliding baseline, and (3) the Holt–Winters method for generalized exponential smoothing. Criteria for comparing the forecasts were the root‐mean‐square error, the median absolute per cent error (MedAPE), and the median absolute deviation. The median‐based criteria showed best overall performance for the Holt–Winters method. The MedAPE measures over the 16 test series averaged 16.5, 11.6, and 9.7 for the non‐adaptive regression, adaptive regression, and Holt–Winters methods, respectively. The non‐adaptive regression forecasts were degraded by changes in the data behaviour in the fixed baseline period used to compute model coefficients. The mean‐based criterion was less conclusive because of the effects of poor forecasts on a small number of calendar holidays. The Holt–Winters method was also most effective at removing serial autocorrelation, with most 1‐day‐lag autocorrelation coefficients below 0.15. The forecast methods were compared without tuning them to the behaviour of individual series. We achieved improved predictions with such tuning of the Holt–Winters method, but practical use of such improvements for routine surveillance will require reliable data classification methods. Copyright © 2007 John Wiley & Sons, Ltd.
The misuse of count data aggregated over time for disease mapping
Authors: Ocaña‐Riola Ricardo 
Published: March 2007

AbstractThe ongoing spread of spatial analysis techniques for small areas has facilitated the publication of mortality and morbidity Atlases based on time periods that group information spanning several years. Although this is a widespread practice, this paper proves that the use of count data aggregated over time for disease mapping may give inappropriate area‐specific relative risk. As a result, both decision‐making and healthcare policies could be affected by inappropriate model specifications using aggregated information over time.The Poisson distribution properties were used in order to quantify the bias in area‐specific relative risk estimation due to count data aggregated over time. A hierarchical Bayesian model with spatio‐temporal random structure is proposed as an alternative to smoothing relative risk if the period of study need to span several years. Methods discussed in this paper were applied to a small‐area survey on male mortality from all causes in Southern Spain for the period 1985–1999. The results suggest that particular caution should be taken when interpreting risk maps based on clustered annual data that use models with no temporal structure to smooth out the rates. Copyright © 2007 John Wiley & Sons, Ltd.
Hydroperoxide as a Prooxidant in the Oxidative Stability of Soybean Oil
Authors: Kim Hyun Jung , Hahm Tae Shik , Min David B. 
Published: March 2007

AbstractFifteen milliliters of soybean oil having peroxide value (PV) of 0, 2, 4, 6, 8, or 10 meq/kg oil in a 35 mL serum bottle was sealed air‐tight with a Teflon rubber septum and aluminum cap and was stored in a forced‐air oven at 50 °C. The oxidative stability of soybean oil was evaluated daily for six days by measuring the headspace oxygen content and volatile compounds in the headspace of a sample bottle by gas chromatography. As the initial PV of the oil increased from 0 to 2, 4, 6, 8 and 10, the headspace oxygen decreased and the volatile compounds increased at p < 0.05. Hydroperoxide accelerated the oxidation of soybean oil. The correlation coefficient (R2) between the headspace oxygen and the volatile compounds was 0.95. The increase of tertiary butyl hydroquinone (TBHQ) from 0 to 50 ppm for the oil of PV 4 or 8 had a significant effect on the oxidative stability at p < 0.05. The increase from 50 to 100 ppm for the oil of PV 4 or 8 did not significantly increase the stability at p > 0.05. The oxidative stability of PV 8 meq/kg and 50 ppm TBHQ was better than the control with PV 0 and 0 ppm TBHQ at p < 0.05. TBHQ was an effective antioxidant to improve the oxidative stability of soybean oil.
Effective strategies for internal outsourcing and offshoring of business services: An empirical investigation
Authors: Zeynep Aksin O. , Masini Andrea 
Published: March 2007

AbstractThe growing pressure to reduce costs and improve efficiency induces many organizations to undertake shared services initiatives. This consolidation and streamlining of common business functions is also known as insourcing, in‐house services, business services, or staff services. While adoption of a shared service structure is viewed by many as an appropriate strategy to pursue, most companies still struggle to devise optimal strategies and to generate adequate returns on investments for their projects, because none of the approaches that are commonly adopted is recognized as universally effective.This paper builds upon the “structure‐environment” perspective to uncover configurations of shared services organizations and to explain why and under what circumstances some of these configurations exhibit superior results. The conceptual model proposed challenges the notion of “best practice” and suggests that the effectiveness of a shared services project depends on the degree of complementarity between the “needs” arising from the environment in which a company operates and the specific capabilities developed to address these needs. The theoretical findings are validated empirically through the analysis of a large sample of European firms that recently undertook initiatives in this domain. Four dominant configurations of shared service organizations are uncovered, and their relationship to performance is explored.
Facilitating offshoring with enterprise technologies: Reducing operational friction in the governance and production of services
Authors: Stratman Jeff K. 
Published: March 2007

AbstractThe development of cheap and robust communications technologies has lowered the cost of conducting business transactions across international boarders and opened up low wage rate global labor markets to firms facing demand for cheap and efficient service delivery. A review of transaction cost theory and operations management models of service process disaggregation reveals parallels between the how firm boundaries are determined and how certain service process elements can be disaggregated from face‐to‐face customer contact. This theoretical background is used to identify challenges to the effective offshoring of service processes. The competitive capability literature offers suggestions as to how firms might acquire the internal capabilities required to manage offshore service processes. Propositions are developed on how the standardized transactional infrastructure of enterprise technologies (and the organizational competencies developed by successful enterprise system adopters) may help mitigate the challenges of offshore governance.
Analysis of interactions among core, transaction and relationship‐specific investments: The case of offshoring
Authors: D Vivek Shiri , Banwet D.K. , Shankar Ravi 
Published: March 2007

AbstractThrough the use of core, transactional and relational specificity constructs, the paper studies how the emphasis of clients’ who move business processes offshore, changes over time to represent complex relationships between investments in core, transaction and relationship‐specific assets. The complex combination of these investments helps clients attain evolving objectives in offshoring alliances. Interpretive Structural Modelling (ISM) has been used to establish changing emphases of the specific elements in offshoring alliances.
Orbitofrontal cortex volume in late life depression: influence of hyperintense lesions and genetic polymorphisms
Authors: TAYLOR WARREN D. , MacFALL JAMES R. , PAYNE MARTHA E. , McQUOID DOUGLAS R. , STEFFENS DAVID C. , PROVENZALE JAMES M. , KRISHNAN K. RANGA R. 
Published: March 2007

ABSTRACTBackgroundOrbitofrontal cortex (OFC) volumetric differences have been reported in depression, but in relatively small samples. Factors associated with these differences are not well described. We examined OFC volumes in a large sample of elderly depressed and non-depressed subjects, exploring the relationship between OFC volume, 5HTTLPR genotype, apolipoprotein E (APOE) genotype and hyperintense lesion volume. We hypothesized that smaller OFC volume would be associated with depression, greater hyperintense lesion volume and severity, and APOE ε4 or 5HTTLPR short allele carriers.MethodA total of 226 depressed and 144 non-depressed older subjects completed 1·5 T magnetic resonance imaging (MRI) and genotyping. OFC volumes and lesion volumes were measured using standardized methods. Lesion severity was additionally rated using the Coffey rating scale. Differences between groups were compared while controlling for age, sex and total cerebral volume; separate models added lesion measures and genetic polymorphisms.ResultsDepressed subjects exhibited smaller OFC volumes. There was a trend for a negative association between white-matter lesion volume and OFC volume; however, rated white-matter lesion severity was significantly negatively associated with OFC volume. There was no association between gray-matter lesion measures or 5HTTLPR genotype and OFC volume. Contrary to our hypothesis, subjects who were APOE ε4 allele positive exhibited larger OFC volumes; in secondary analyses, this finding was limited to the non-depressed group.ConclusionsReduced OFC volumes are seen in depression and associated with greater severity of white-matter lesions. Healthy subjects who are APOE ε4 allele positive exhibited larger OFC volumes. This finding should be examined in other populations.