bluuebunny/crossref_metadata_2025 huggingface dataset:
Curing a meagre health care system by lean methods—translating ‘chains of care’ in the Swedish health care sector
Authors: Trägårdh Björn , Lindberg Kajsa
Published: December 2004

The purpose of this article is to discuss what happens when work embedded in a ‘meagre’†

‘Meagre’ is chosen as a term to describe a critical state in an organizational field where resources are relatively scarce, i.e. in relation to the prescribed task. ‘Lean’ is a term to describe an organizational concept in order to simultaneously rationalize and develop production.

organizational context is changed by lean production‐related methods. The article is based on studies of seven lean production‐inspired projects in the Swedish health care sector, a sector already poor due to organizational slack. The projects were directed to develop ‘health care chains’, an organizational concept regarded as a way to rationalize health care organizations as well as to develop them, i.e. increase productivity, quality from a customer perspective and quality of working conditions. The article analyses the projects from an interpretative perspective and discusses how modern management models with ambitions to concurrently rationalize and develop organizations—e.g. lean production and health care chains—are used in a ‘meagre’ organizational field. As an outcome, a model is presented that explores what is beyond simple imitations and unique translations of ideas when a new concept is implemented in local organizations. Copyright © 2004 John Wiley & Sons, Ltd.
Quality‐based purchasing in health care
Authors: Waters Hugh R. , Morlock Laura L. , Hatt Laurel
Published: December 2004

Quality‐based purchasing is a growing trend that seeks to improve healthcare quality through the purchaser‐provider relationship. This article provides a unifying conceptual framework, presents examples of the purchaser‐provider relationship in countries at different income levels, and identifies important supporting mechanisms for quality‐based purchasing. As countries become wealthier, a higher proportion of healthcare spending is channeled through pooled arrangements, allowing for greater involvement of purchasers in promoting the quality of service provision.

Global and line item budgets are the most common type of provider payment system in low and middle‐income countries. In these countries, improving public hospital performance through contracting and incentives is a key issue. In middle and high‐income countries, there are several documented examples of governments contracting to private or non‐governmental health care providers, resulting in higher perceived quality of care and lower delivery costs. Encouraging quality through employer purchasing arrangements has been promoted in several countries, particularly the United States.

Community‐based financing schemes are an increasingly common form of health financing in parts of sub‐Saharan Africa and Asia, but these schemes still cover less than 10% of national populations in countries in which they are active. To date, there is little evidence of their impact on healthcare quality.

The availability of information—concerning healthcare service provision and outcomes—determines the options for establishing and monitoring contract provisions and promoting quality. Regardless of the context, quality‐based purchasing depends critically on information—reporting, monitoring, and providing useful information to healthcare consumers. In many low and middle‐income countries, the lack of availability of information is the principal constraint on measuring performance, a critical component of quality‐based purchasing. Copyright © 2004 John Wiley & Sons, Ltd.
Internal energy distribution in electrospray ionization
Authors: Naban‐Maillet Jessie , Lesage Denis , Bossée Anne , Gimbert Yves , Sztáray Judit , Vékey Károly , Tabet Jean‐Claude
Published: December 2004

Internal energies and energy distributions were studied using the ‘survival yield’ method developed previously. In addition to conventional benzylpyridinium salts, protonated esters (fragmenting by rearrangement) and protonated leucine enkephalin were also used, extending the validity of the technique. Fragmentation processes were studied in the cone voltage region and modeled by the RRKM‐based MassKinetics program. The results show that the shapes of the energy distributions are similar to thermal distributions. The mean internal energies are very similar for all compound classes studied, and show a linear increase with collision energy in the 10–50 eV region. Copyright © 2004 John Wiley & Sons, Ltd.
Structure and Properties of Novel Fibers Spun from Cellulose in NaOH/Thiourea Aqueous Solution
Authors: Ruan Dong , Zhang Lina , Zhou Jinping , Jin Huiming , Chen Hui
Published: December 2004

Summary: Cellulose was dissolved rapidly in a NaOH/thiourea aqueous solution (9.5:4.5 in wt.‐%) to prepare a transparent cellulose solution, which was employed, for the first time, to spin a new class of regenerated cellulose fibers by wet spinning. The structure and mechanical properties of the resulting cellulose fibers were characterized, and compared with those of commercially available viscose rayon, cuprammonium rayon and Lyocell fibers. The results from wide angle X‐ray diffraction and CP/MAS 13C NMR indicated that the novel cellulose fibers have a structure typical for a family II cellulose and possessed relatively high degrees of crystallinity. Scanning electron microscopy (SEM) and optical microscopy images revealed that the cross‐section of the fibers is circular, similar to natural silk. The new fibers have higher molecular weights and better mechanical properties than those of viscose rayon. This low‐cost technology is simple, different from the polluting viscose process. The dissolution and regeneration of the cellulose in the NaOH/thiourea aqueous solutions were a physical process and a sol‐gel transition rather than a chemical reaction, leading to the smoothness and luster of the fibers. This work provides a potential application in the field of functional fiber manufacturing.

A bundle of fibers with a similar circular cross‐section, indicating the homogeneous and smooth surface of the fibers.

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A bundle of fibers with a similar circular cross‐section, indicating the homogeneous and smooth surface of the fibers.
Fiber Formation in Medium and Ultra‐High‐Molecular‐Weight Polyhydroxybutyrate Blends under Shear Flow
Authors: Sharma Lakshmi , Ogino Yoshino , Kanaya Toshiji , Iwata Tadahisa , Doi Yoshiharu
Published: December 2004

Summary: Polyhydroxybutyrate (PHB) is an ideal bioplastic, however, this polymer undergoes a severe embrittlement process because of its spherulitic structure, rendering the material brittle. Using a series of in‐situ rheo techniques, we have previously observed only the rapid initial stage of shish formation, we term a partial shish, which existed at high shears in medium‐molecular‐weight PHB, $\overline M _{\rm w}$ = 360 000. The shish kebab morphology is anticipated to remove or severely lessen this embrittlement process whilst providing new properties and applications. For medium and ultra high‐molecular‐weight (MMWT, $\overline M _{\rm w}$ = 360 000/UHMWT, $\overline M _{\rm w}$ = 5 × 106) PHB 99/1 and 99.5/0.5 blends only a partial shish is identified. However, the initial shish formation stage and subsequent stages were observed at 98/2 and 97/3 blend ratios resulting in a complete shish, we term the full shish, and fiber formation was evident. We believe this fiber morphology achieved by high molecular weights is crucial to sustaining the shish kebab structure for an excessive period.

Left: In‐situ rheo‐light scattering micrograph; 97/3 MMWT/UHMWT PHB at 100 s−1 for 1 s shear shish held at 75 s. Right: In situ rheo‐optical micrograph; PHB fiber morphology observed at 50 s−1 for 2 s shear 98/2 MMWT/UHMWT PHB after 1 min.

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Left: In‐situ rheo‐light scattering micrograph; 97/3 MMWT/UHMWT PHB at 100 s−1 for 1 s shear shish held at 75 s. Right: In situ rheo‐optical micrograph; PHB fiber morphology observed at 50 s−1 for 2 s shear 98/2 MMWT/UHMWT PHB after 1 min.
Nanocomposite Formation in Hydrogenated Nitrile Rubber (HNBR)/Organo‐Montmorillonite as a Function of the Intercalant Type
Authors: Gatos Konstantinos G. , Sawanis Nikolaos S. , Apostolov Anton A. , Thomann Ralf , Karger‐Kocsis József
Published: December 2004

Summary: Hydrogenated acrylonitrile butadiene rubber (HNBR) was melt compounded with montmorillonite (MMT) and organophilic modified MMTs prior to sulfur curing. In contrast to the micro‐composite formation resulting from the compounding of the HNBR and pristine MMT, the modified MMTs (i.e., octadecylamine: MMT‐ODA, octadecyltrimethylamine: MMT‐ODTMA, methyltallow‐bis(2‐hydroxyethyl) quaternary ammonium: MMT‐MTH intercalants) produced nanocomposites. It was found that the organoclay with primary amine intercalant (cf. MMT‐ODA) gave confined structures along with the exfoliated/intercalated structures. This was traced to its reactivity with the curatives. By contrast, the organoclays containing less reactive quaternary ammonium compounds (cf. MMT‐ODTMA, MMT‐MTH) were exfoliated and intercalated based on X‐ray diffraction (XRD) and transmission electron microscopy (TEM) results. The hydroxyl functional groups of the MMT‐MTH supported the clay dispersion. The better adhesion between MMT‐MTH and HNBR was explained by hydrogen bonding between the hydroxyl groups of the intercalant and the acrylonitrile group of the HNBR matrix. This HNBR/MMT‐MTH nanocomposite showed the best mechanical properties as verified by tensile mechanical tests and dynamic mechanical thermal analysis (DMTA). The high tensile strength along with the high elongation at break for the rubber nanocomposites were attributed to the ability of the ‘clay network’ to dissipate the input energy upon uniaxial loading.

Scheme of failure development in rubber/organoclay mixes with poor (a) and good (b) dispersion of the clay layers.

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Scheme of failure development in rubber/organoclay mixes with poor (a) and good (b) dispersion of the clay layers.
Miscibility and Crystallization Behaviors of Polyamide 6/Polytetrafluoroethylene Blends
Authors: Song Rui , Zhao Jun , Stamm Manfred
Published: December 2004

Summary: The miscibility and crystallization behaviors of polyamide 6 (PA 6)/polytetrafluoroethylene (PTFE) blends, prepared via reactive extrusion, are systematically investigated by means of wide‐angle X‐ray diffraction (WAXD), differential scanning calorimetry (DSC), and dynamic mechanical thermal analysis (DMTA). WAXD measurements show that no co‐crystallization occurred between two components, while DSC and DMTA measurements suggest that a certain degree of miscibility between them might exist due to the formation of some copolymers during the reactive extrusion.

DMTA curves for the pure PA 6 sample and PA 6/PTFE blends with various compositions.

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DMTA curves for the pure PA 6 sample and PA 6/PTFE blends with various compositions.
Static and Dynamic Mechanical Behavior of Electron Beam‐Cured Monomer and Monomer/Liquid Crystal Systems
Authors: Olivier Aline , Benkhaled Leila , Pakula Tadeusz , Ewen Bernd , Best Andreas , Benmouna Mustapha , Maschke Ulrich
Published: December 2004

Summary: This paper discusses static and dynamic mechanical properties of electron beam‐cured mixtures made of the nematic liquid crystal (LC) E7 and either tripropyleneglycol diacrylate (TPGDA) or propoxylated glycerol triacrylate (GPTA) as monomers differing essentially by their functionality. Dilution of the initial mixture with LC leads to a significant weakening of the film mechanical strength. Strong effects were found on Young modulus and rubbery state modulus. As the concentration of LC increases, these mechanical parameters drop significantly together with the glass transition temperature of the polymer showing a plasticizing effect. The results for the glass transition temperatures for the polymer and the LC were confirmed by thermograms obtained by differential scanning calorimetry.

Storage tensile modulus versus temperature of EB‐cured TPGDA/E7 films for different LC concentrations.

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Storage tensile modulus versus temperature of EB‐cured TPGDA/E7 films for different LC concentrations.
Molecular evaluation of ablative therapy of Barrett's oesophagus
Authors: Hage Mariska , Siersema Peter D , Vissers Kees J , Steyerberg Ewout W , Haringsma Jelle , Kuipers Ernst J , van Dekken Herman
Published: December 2004

Barrett's oesophagus is a major risk factor for developing oesophageal adenocarcinoma. Ablation by argon plasma coagulation (APC) and photodynamic therapy (PDT) is currently under investigation for the removal of metaplastic and dysplastic Barrett's oesophagus. This study examined the effect of ablative therapy on Barrett's oesophagus at cell‐cycle and genetic levels. The premalignant potential of residual or recurring Barrett's oesophagus was assessed by p53 immunohistochemistry, Ki67‐related proliferative capacity, and DNA ploidy status (ie an abnormal chromosome 1 number) as measured by interphase in situ hybridization. Twenty‐nine patients with Barrett's oesophagus (23 male and 6 female, mean age 58 years, mean length of Barrett's oesophagus 4 cm) were treated with APC or PDT. Intestinal metaplasia without dysplasia was present in 16 patients, low‐grade dysplasia in five, and high‐grade dysplasia in eight patients. Biopsy samples were obtained at regular intervals (mean follow‐up 20 months, range 6–36 months). One month after the first ablation, Barrett's oesophagus was no longer identified, either endoscopically or histologically, in nine patients (32%). At this time point, significant down‐grading was achieved for abnormal chromosome 1 numbers (p = 0.020) and Ki67‐defined proliferation (p = 0.002). Patients with residual Barrett's oesophagus were additionally treated with APC, resulting in the elimination of Barrett's oesophagus in 76% of all patients. However, at the last follow‐up endoscopy, metaplasia without dysplasia was still present in five patients, and low‐ and high‐grade dysplasia were each present in one patient. An abnormal chromosome 1 number and p53 protein overexpression were detected only in the high‐grade dysplastic lesion, but increased proliferation was still present in the majority of these persisting cases. Although endoscopic removal of Barrett's oesophagus by ablative therapies is possible in the majority of patients, histologically complete elimination cannot be achieved in all cases. Persistent Barrett's oesophagus may still harbour molecular aberrations and must therefore be considered still to be at risk of progression to adenocarcinoma. Copyright © 2004 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Evidence of increased microvessel density and activation of the hypoxia pathway in tumours from the hereditary leiomyomatosis and renal cell cancer syndrome
Authors: Pollard Patrick , Wortham Noel , Barclay Ella , Alam Afrina , Elia George , Manek Sanjiv , Poulsom Richard , Tomlinson Ian
Published: December 2004

The Mendelian tumour syndromes hereditary leiomyomatosis and renal cell cancer (HLRCC) and hereditary paragangliomatosis with phaeochromocytomas (HPGL) result from mutations in nuclear genes (FH and SDHB/C/D, respectively) that encode Krebs cycle enzymes. HPGL tumours are highly vascular and there is evidence that inactivation of SDH leads to activation of the hypoxia/angiogenesis pathway. In contrast, uterine leiomyomas are not generally regarded as particularly vascular lesions. In order to test the possibility that activation of the hypoxia/angiogenesis pathway contributes to tumourigenesis in HLRCC, increased vascularity and hypoxia pathway activation were searched for in HLRCC tumours. Microvessel density was markedly higher in uterine leiomyomas from HLRCC than in the surrounding myometrium; it was notable that sporadic uterine leiomyomas were actually less vascular than normal myometrium. In HLRCC tumours, there was increased expression of transcripts from the hypoxia‐responsive genes vascular endothelial growth factor (VEGF) and BNIP3; sporadic uterine leiomyomas did not show these changes. All uterine leiomyomas showed decreased expression of thrombospondin 1. Although sporadic and HLRCC uterine leiomyomas appear to have identical morphology, their pathways of tumourigenesis may be fundamentally different. As is the case in HPGL, it is probable that failure of the Krebs cycle in HLRCC tumours causes inappropriate signalling that the cell is in a hypoxic state, leading to angiogenesis and perhaps directly to clonal expansion and tumour growth through some uncharacterized, cell‐autonomous effect. Copyright © 2004 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Systematic identification and molecular characterization of genes differentially expressed in breast and ovarian cancer
Authors: Dahl Edgar , Sadr‐Nabavi Ariane , Klopocki Eva , Betz Beate , Grube Susanne , Kreutzfeld Rene , Himmelfarb Marina , An Han‐Xiang , Gelling Stephen , Klaman Irina , Hinzmann Bernd , Kristiansen Glen , Grützmann Robert , Kuner Ruprecht , Petschke Beate , Rhiem Kerstin , Wiechen Kai , Sers Christine , Wiestler Otmar , Schneider Achim , Höfler Heinz , Nährig Jörg , Dietel Manfred , Schäfer Reinhold , Rosenthal André , Schmutzler Rita , Dürst Matthias , Meindl Alfons , Niederacher Dieter
Published: December 2004

The identification of novel disease‐associated genes in gynaecological tumours has important implications for understanding the process of tumourigenesis and the development of novel treatment regimens. cDNA libraries from disease tissues may represent a valuable source to identify such genes. Recently, a bio‐informatic procedure based on an ‘electronic Northern’ approach was established to screen expressed sequence tag (EST) libraries for genes differentially expressed in tumour and normal tissues, and identified 450 candidate genes differentially expressed in breast and ovarian cancer. In this report, the validation of an initial set of 40 candidate genes, which were selected due to their localization in chromosomal regions frequently altered in gynaecological tumours, is described. Differential expression of 29 of these genes, including three uncharacterized novel genes, was confirmed by applying cancer profiling arrays with 106 matched pairs of tumour/normal cDNAs and quantitative reverse transcription‐polymerase chain reaction (RT‐PCR) on 60 clinical specimens. The majority of these differentially expressed genes have not been described previously in the context of breast and ovarian cancer, and may constitute novel diagnostic markers for these tumour entities. Copyright © 2004 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Mast cell tryptase may modulate endothelial cell phenotype in healing myocardial infarcts
Authors: Somasundaram Porur , Ren Guofeng , Nagar Himanshu , Kraemer Daniela , Mendoza Leonardo , Michael Lloyd H , Caughey George H , Entman Mark L , Frangogiannis Nikolaos G
Published: December 2004

Mast cells and macrophages infiltrate healing myocardial infarcts and may play an important role in regulating fibrous tissue deposition and extracellular matrix remodelling. This study examined the time‐course of macrophage and mast cell accumulation in healing infarcts and studied the histological characteristics and protease expression profile of mast cells in a canine model of experimental infarction. Although macrophages were more numerous than mast cells in infarct granulation tissue, macrophage density decreased during maturation of the scar, whereas mast cell numbers remained persistently elevated. During the inflammatory phase of infarction, newly recruited leucocytes infiltrated the injured myocardium and appeared to be clustered in close proximity to degranulating cardiac mast cells. During the proliferative phase of healing, mast cells had decreased granular content and were localized close to infarct neovessels. In contrast, macrophages showed no selective localization. Mast cells in healing canine infarcts were alcian blue/safranin‐positive cells that expressed both tryptase and chymase. In order to explain the pro‐inflammatory and angiogenic actions of tryptase—the major secretory protein of mast cells—its effects on endothelial chemokine expression were examined. Chemokines are chemotactic cytokines that play an important role in leucocyte trafficking and angiogenesis and are highly induced in infarcts. Tryptase, a proteinase‐activated receptor (PAR)‐2 agonist, induced endothelial expression of the angiogenic chemokines CCL2/MCP‐1 and CXCL8/IL‐8, but not the angiostatic chemokine CXCL10/IP‐10. Endothelial PAR‐2 stimulation with the agonist peptide SLIGKV induced a similar chemokine expression profile. Mast cell tryptase may exert its angiogenic effects in part through selective stimulation of angiogenic chemokines. Copyright © 2004 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
An improved methodology for modeling neurobehavioral late‐effects of radiotherapy in pediatric brain tumors
Authors: Ris M. Douglas , Ryan Patricia McDonough , Lamba Michael , Brenemen John , Cecil Kim , Succop Paul , Ball William
Published: December 2004

Background

Technical advances in radiation oncology provide new opportunities to study neurobehavioral outcomes of radiation therapy (RT) in children treated for brain tumors.

Methods

In this study, we describe an approach to modeling late‐effects using integral biologically effective dose (IBED) combined with improved measurement of critical neuropsychological functions.

Results

IBED was found to provide more differentiated information about dose distribution than prescribed dose in five subjects treated for brain tumors. Furthermore, IBED was more closely related than was prescribed dose to specific changes in Attention 2–3 years post‐RT.

Conclusions

Results support the feasibility of this methodology as well as promising preliminary evidence of the relationship of IBED to the construct of Attention. Improved modeling could lead to more refined radiation therapy protocols that preserve critical neuropsychological functions and also provide new insights into the treatment of neurobehavioral sequelae. © 2004 Wiley‐Liss, Inc.
Renal impairment and hypertension in brain tumor patients treated in childhood are mainly associated with cisplatin treatment
Authors: Pietilä Sari , Ala‐Houhala Marja , Lenko Hanna L. , Harmoinen Aimo P.T. , Turjanmaa Väinö , Mäkipernaa Anne
Published: December 2004

Background

This study was designed to evaluate the renal consequences of the treatment of brain tumor patients diagnosed in childhood.

Procedure

One hundred four primary brain tumor patients diagnosed before 17 years of age from 1983 to 1997 had been treated in Tampere University Hospital, Finland. Of the 80 survivors 52 (65.0%) were examined at a median age of 14.4 years (range 3.8–28.7) and median 6.0 years (range 1.2–14.8) after the last treatment. The main outcome measures were blood pressure (BP), renal function, and calcium metabolism.

Results

Eight patients (15.4%) were hypertensive. Elevated BP was observed especially after exposure both to cisplatin and cranial irradiation. Spinal radiation did not increase the risk of elevated BP. Other adverse effects were observed only in patients treated with cisplatin. Five out of 14 patients treated with cisplatin evinced renal glomerular dysfunction (GFR < 87 mL/min/1.73 m2) immediately after treatment. They had a high cumulative dose of cisplatin (490–880 mg/m2). Recovery from renal glomerular dysfunction was observed in one patient. Nine of 14 patients were hypomagnesemic at the close of cisplatin treatment. Thereafter the magnesium level decreased in 10/14 cases (P = 0.006). During the study 10/14 were hypomagnesemic (P < 0.001); one evinced severe symptomatic hypomagnesemia. Low plasma phosphate (P = 0.016) and potassium levels (P = 0.026), tubular proteinuria (P = 0.055), metabolic alkalosis (P = 0.071), and hyperuricemia (P = 0.114) were also more common in patients on cisplatin treatment.

Conclusions

Elevated BP is common among brain tumor patients treated in childhood. After cisplatin treatment renal glomerular dysfunction appears mostly to be permanent. Persistent and even progressive changes in renal tubular function are seen. © 2004 Wiley‐Liss, Inc.
What characteristics are associated with screening positive for microalbuminuria in patients with diabetes in the community?
Authors: Levene LS , McNally PG , Fraser RC , Lowy AGJ
Published: December 2004

The community prevalence of microalbuminuria in patients with diabetes is unknown. The aims of this study were to determine the community prevalence of microalbuminuria and to identify associated characteristics with particular reference to ethnicity.

The study was undertaken in 18 Leicestershire general practices. Subjects were recruited either by a written invitation to the entire diabetic register over 16 years of age or by personal invitation to all those attending a practice diabetic clinic. Microalbuminuria status was determined from three first morning urine specimens, using the albumin:creatinine ratio (ACR), microalbuminuria being defined as at least 2.5 mg/mmol in males and 3.5 mg/mmol in females in two or more samples. Nine patient covariates were recorded for each subject.

In all, 1860 patients (an estimated overall response rate of 67%) consented to participate (1373 white, 451 Indo‐Asian, 36 other ethnic groups); 1362 (73.2%) completed screening. The prevalence of microalbuminuria in patients with diabetes recruited to the study was 19.3%. The characteristics independently associated with a higher prevalence of microalbuminuria were current insulin use, current smoking, older age, higher systolic blood pressure and poorer metabolic control, but there was no significant association with duration of diabetes, gender or ethnicity.

Screening for microalbuminuria using ACR is feasible in the community. Our estimate of the community‐wide prevalence of microalbuminuria (19.3%) is lower than some earlier population‐ and many hospital‐based estimates. Due to difficulties in recruiting, in particular Indo‐Asian subjects, the precise community prevalence of microalbuminuria could only be estimated, although some characteristics of the screened population were representative of the larger unscreened Leicestershire diabetic population. The factors shown to be associated with microalbuminuria were current insulin use, current smoking, older age, higher systolic blood pressure and poorer metabolic control. If Indo‐Asian ethnicity is associated with microalbuminuria, then this association is not as strong as other characteristics. These findings suggest that interventions to delay the progression of diabetic nephropathy support smoking cessation, and better glycaemic and blood pressure control—areas that require sustained action. Copyright ©2004 John Wiley & Sons, Ltd.
Computational study of alkyllithium/pyridine derivative systems as initiators for the living anionic polymerization of methyl methacrylates
Authors: Catak S. , Aviyente V. , Nugay T.
Published: December 2004

The reactivity of n‐butyllithium (n‐BuLi) toward pyridine derivatives (pyridine, pyridazine, pyrimidine, and 1,3,5‐triazine) was subjected to a computational study to determine the most suitable n‐BuLi/heterocyclic ring system as an initiator for the anionic polymerization of methyl methacrylate (MMA). These systems were suggested to prevent side reactions occurring through n‐BuLi attack on the carbonyl carbon of MMA by sterically blocking the initiator. The initiation reaction was modeled with the B3LYP methodology 6‐31+G*. Activation barriers were used to analyze the reactivity of each n‐BuLi/heterocyclic ring system. Computational results showed that n‐BuLi/triazine had a significantly lower activation barrier. Therefore, n‐BuLi/triazine was the suggested initiator system for the anionic polymerization of poly(methyl methacrylate). © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 455–467, 2005
Cathodoluminescent characteristics of Sm‐doped ZnAl2O4 nanostructured powders
Authors: Martinez‐Sanchez E. , Garcia‐Hipolito M. , Guzman J. , Ramos‐Brito F. , Santoyo‐Salazar J. , Martinez‐Martinez R. , Alvarez‐Fregoso O. , Ramos‐Cortes M. I. , Mendez‐Delgado J. J. , Falcony C.
Published: December 2004

Cathodoluminescent (CL) powders of zinc aluminate activated with samarium ions have been prepared by a co‐precipitation chemical process. Different doping concentrations in the start mixture and sintering temperatures for the precipitated powder were studied. It was observed that the crystalline characteristics of the powders depend upon the sintering temperature. For temperatures higher than 450 °C, the powders presented the cubic spinel phase with a lattice parameter value of 8.0756 Å, and grain sizes from 50 to 100 nm with semispherical shape. The CL emission spectra showed broad bands localized at 564, 602, 644, and 703 nm associated with 4G5/2 → 6H5/2, 4G5/2 → 6H7/2, 4G5/2 → 6H9/2, and 4G5/2 → 6H11/2 transitions in the Sm3+ ions, respectively. Concentration quenching of the cathodoluminescence occurred at about 4.26 at% of the activator (Sm) concentration inside the sintered powders. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Atomic force microscopy study of hexagonal boron nitride film growth on 6H‐SiC (0001)
Authors: Chen Wei , Loh Kian Ping , Lin Ming , Liu Rong , Wee Andrew T. S.
Published: December 2004

The growth of hexagonal Boron Nitride films (h‐BN) on 6H‐SiC (0001) using plasma‐excited borazine has been studied. On 6H‐SiC (0001), the growth of pin‐hole free, compact h‐BN film is difficult due to poor wetting properties between h‐BN and 6H‐SiC. The strained BN layer releases its elastic energy by a morphological instability at the interface. This strain relief mechanism gives rise to a buckling of the film into longitudinal islands and round trenches between 500–700 °C. At 300 and 900 °C however, the strained islands can attain their minimum‐energy size to form homogeneously‐sized spherical islands with diameter of ∼500 nm. Compositional analysis of the BN films grown at 900 °C using XPS shows that these are actually BCxN film with x ∼ 0.15, whereas the films grown at 300 °C have less carbon incorporation but higher O content. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Diagnostic accuracy of fetal renal pelvis anteroposterior diameter as a predictor of uropathy: a prospective study
Authors: Bouzada M. C. F. , Oliveira E. A. , Pereira A. K. , Leite H. V. , Rodrigues A. M. , Fagundes L. A. , Gonçalves R. P. , Parreiras R. L.
Published: December 2004

Objective

The purpose of this study was to assess the accuracy of prenatal ultrasound measurement of anteroposterior renal pelvis diameter (APD) to discriminate between significant uropathy and idiopathic renal pelvis dilatation.

Methods

One‐hundred‐and‐three neonates who were found to have fetal renal pelvis dilatation, defined as presence of an APD ≥ 5 mm, underwent systematic investigation for uropathies and were prospectively followed. An ultrasound scan was performed after the first week of postnatal life and all infants underwent a voiding cystourethrogram. Neonates with an APD larger than 10 mm underwent renal scintigraphy. Ultrasound scans, clinical examination and laboratory reviews were scheduled at 6‐month intervals. Receiver–operating characteristics (ROC) curves were constructed to determine the best cut‐offs for APD to identify renal units with significant uropathy as well as those requiring surgical intervention. Significant uropathy was defined as the presence of well‐established urinary tract abnormalities or when there was abnormal renal scintigraphy.

Results

The estimated area under the curve for APD was 0.900 (95% CI, 0.841–0.942) indicating excellent power to discriminate between idiopathic pelvis dilatation and significant uropathy. The sensitivity and specificity for the 7.5 mm cut‐off point were 97.9% and 40.6%, respectively. To identify infants who required surgical intervention, the calculated area under the curve was 0.953 (95% CI, 0.908–0.980).

Conclusion

Our results suggest that measurement of APD is an excellent test to identify fetuses with significant uropathy, as well as those requiring postnatal intervention. Copyright © 2004 ISUOG. Published by John Wiley & Sons, Ltd.
Variability in dilatation of the fetal renal pelvis during a bladder filling cycle
Authors: Damen‐Elias H. A. M. , Stigter R. H. , De Jong T. P. V. M. , Visser G. H. A.
Published: December 2004

Objective

To investigate the variation in the dimensions of the fetal renal pelvis in relation to the degree of bladder filling in fetuses with mild pyelectasis.

Methods

Eighteen third‐trimester pregnant women with mild uni‐ or bilateral fetal pyelectasis, defined as an anteroposterior (A‐P) diameter of the renal pelvis between 5 and 10 mm, were recruited for the study. The women were examined for 2–3 h by ultrasound. The A‐P and transverse dilatation of the renal pelvis and the bladder dimensions (to calculate fetal bladder volume) were measured at 2–3‐min intervals. Postnatally, all infants were investigated by ultrasound at 3–4 months.

Results

In 6/18 fetuses a consistent relationship between the size of the renal pelvis and bladder filling was found, with a mean difference in renal pelvic diameter before and after voiding of 6.7 mm and a largest observed difference of 14.3 mm. In 12/18 fetuses no such relationship was found. Postnatally, five infants were referred to a pediatric urologist. The investigations in these five infants could not confirm the hypothesis that variation in renal pelvic size in relation to bladder size may predict prenatal vesicoureteric reflux (VUR).

Conclusions

In mild pyelectasis the size of the renal pelvis is highly variable in one‐third of cases. The association with bladder volume and micturition suggests evidence of VUR, but this could not be proven. If cut‐off values are used to differentiate between normal and abnormal renal pelvic size then not only gestational age but also the degree of bladder filling at the time of measurement should be taken into account. Caution should be expressed when the diagnosis of a possible urological anomaly is based on a single measurement during just one investigation. Copyright © 2004 ISUOG. Published by John Wiley & Sons, Ltd.
How early are fetal cerebral sulci visible at prenatal ultrasound and what is the normal pattern of early fetal sulcal development?
Authors: Toi A. , Lister W. S. , Fong K. W.
Published: December 2004

Objectives

To evaluate the time of appearance and pattern of development of fetal cerebral sulci at prenatal ultrasound.

Methods

We studied 50 normal fetuses for visibility of cerebral sulci, especially sulci which appear early in anatomical studies, namely the parieto‐occipital fissure, calcarine sulcus, cingulate sulcus, convexity sulci and insula/Sylvian fissure. The gestational ages of the fetuses studied ranged from 15.6 to 29.6 weeks.

Results

Sulci could be seen by transabdominal ultrasound as early as 18.5 weeks. Medial hemispheric sulci and the insula were visible earlier and more confidently than convexity sulci. The earliest gestational ages at which specific sulci could be seen in any fetus were as follows: parieto‐occipital fissure 18.5 weeks, calcarine sulcus 18.5 weeks, cingulate sulcus 23.2 weeks and convexity sulci 23.2 weeks. In the present series, the gestational ages at which these sulci were always visible were as follows: parieto‐occipital fissure >20.5 weeks, calcarine sulcus >21.9 weeks, cingulate sulcus >24.3 weeks and convexity sulci >27.9 weeks. The insula and its margin (the circular sulcus) and the overgrowing opercula undergo characteristic maturation. The circular sulcus at the margin of the insula was initially smooth but started becoming angular after about 17 weeks as it started to be overgrown by the parietal and temporal lobe opercula. Initially the insula/operculum angle was obtuse. An acute angle was first evident at 23.2 weeks and in all fetuses older than 24.5 weeks. Our ultrasound data were consistent with anatomical studies and fetal magnetic resonance imaging findings.

Conclusions

Some cerebral sulci can be seen at prenatal ultrasound as early as 18.5 weeks. Familiarity with the normal pattern of sulcal development and the discriminating gestational ages for the appearance of different sulci may allow early suspicion of lissencephaly. Copyright © 2004 ISUOG. Published by John Wiley & Sons, Ltd.
Can proboscis monkeys be successfully maintained in captivity? A case of swings and roundabouts
Authors: Agoramoorthy G. , Alagappasamy C. , Hsu M.J.
Published: December 2004

Although most western zoos have experienced difficulties in maintaining proboscis monkeys, the Singapore Zoo has managed to sustain a social group of proboscis monkeys housed in a large naturalistic exhibit since 1998. Within 3 years after the monkeys were brought to the zoo, five offspring were produced, all of which survived. Natural forest vegetation from 20 plant species was provided along with a staple diet of about seven different species on a daily basis. The calcium and sodium contents of the plant items consumed by monkeys in the Singapore Zoo were similar to those in the diet of wild proboscis monkeys in Borneo. However, the levels of other minerals, such as iron, magnesium, manganese, potassium, zinc, and phosphorus, were significantly lower in the natural vegetation consumed by the monkeys compared to the wild diet. Food supplements such as primate biscuits, cod liver oil, boiled egg, multivitamins, and mineral syrup further ensured a more balanced diet for the captive monkeys. The data presented here show that zoos can maintain these rare Colobine monkeys successfully by provide them with a natural diet, along with appropriate husbandry and hygiene practices, minimal human interference, and applied nutritional science. The husbandry and nutritional management model presented in this paper could be of use to other institutions around the world. Zoo Biol 23:533–544, 2004. © 2004 Wiley‐Liss, Inc.
Computing biomass consumption from prey occurrences in Indian wolf scats
Authors: Jethva Bharat D. , Jhala Yadvendradev V.
Published: December 2004

We determined a relationship between biomass consumed per collectable scat and prey weight. We fed prey items (ranging from rodent (0.75 kg) to juvenile cattle (65 kg), covering the normal weight range for prey of the Indian wolf (Canis lupus papllipes)) to groups of two to five captive wolves in 13 feeding trials at Sakkarbaug Zoo, Junagadh, India. The prey biomass eaten per collectable scat (Y) increased as the live body weight of prey (X) increased (Y=0.0148X+0.135; R2=0.87; F=75.8; df=1,11; P<0.001). The slope of our regression (0.015; tropical domestic prey) did not differ from that reported by Floyd et al. [1978] (temperate wild prey, P=0.17); therefore, we pooled the data from both studies and derived a combined regression (Y=0.0182X+0.217; R2=0.77; df=1,20; P<0.001). In addition to the widely accepted explanation that the surface‐area‐to‐mass ratio is larger for small prey, we found that this relationship reflected the fact that percent utilization was greater, and digestibility was lower for smaller prey. Zoo Biol 23:513–520, 2004. © 2004 Wiley‐Liss, Inc.
Comparison of the thermoregulatory response of buffaloes and tropical cattle, using fluctuations in rectal temperature, skin temperature and haematocrit as an index
Authors: KOGA A. , SUGIYAMA M. , DEL BARRIO A. N. , LAPITAN R. M. , ARENDA B. R. , ROBLES A. Y. , CRUZ L. C. , KANAI Y.
Published: December 2004

In previous comparative studies of buffaloes and temperate cattle, a greater increase in rectal temperature (RT) and skin temperature (ST), and a greater decrease in haematocrit (Ht) have been observed in buffaloes than in temperate cattle with an increase in ambient temperature (AT). Our series of previous experiments suggested that great changes in RT, ST and Ht are induced in buffaloes by a marked increase in blood flow from the body core to the surface, which accelerates dissipation of heat from the skin surface. On the basis of these suggestions, the present study was undertaken to compare fluctuations in RT, ST and Ht between buffaloes and tropical cattle. Fluctuations in the aforementioned parameters, particularly RT and Ht, were greater in buffaloes than in cattle. Moreover, the correlation for RT or Ht v. AT was significant for buffaloes (r=0·33 and −0·37, respectively) but not for cattle. The correlation coefficient for ST v. AT was significant in both species, but was greater in buffaloes (r=0·63) than in cattle (r=0·56). These results demonstrate that with changes in ambient temperature, RT, ST and Ht fluctuate much more in buffaloes than in tropical cattle, as found previously for temperate cattle. Therefore, the distinctive thermoregulatory responses of buffalo are confirmed as being specific to this species.
The effects of timing of control of weeds on the yield of winter oilseed rape (Brassica napus), in the context of the potential commercialization of herbicide-tolerant winter rape
Authors: FREEMAN S. E. , LUTMAN P. J. W.
Published: December 2004

Three experiments have investigated the effect of the timing of control of infestations of volunteer barley (Hordeum vulgare), Stellaria media and Galium aparine on the growth and yield of winter oilseed rape (Brassica napus). Although the experiments used conventional herbicides to achieve the different timings of control, the work was done in the context of the commercialization of herbicide-tolerant oilseed rape, where treatments could be applied at any time from autumn to spring. In the three seasons studied, oilseed rape growth was particularly vigorous in the autumn and, as a consequence, the competitive impact of the weeds was lower than anticipated. Untreated volunteer barley and G. aparine reduced yields in one and two experiments, respectively. However, in all experiments volunteer barley reduced crop growth in winter and spring severely, even though January treatments prevented yield loss in these vigorous crops. Delayed control of this weed would not be advisable if the weed was particularly dense or the crop less vigorous. In contrast, the G. aparine had no effect on crop growth and was only really apparent in the crop in late summer, so delaying treatment until even March would not put yields at risk. In one year, S. media markedly reduced crop growth in late winter but in the second experiment this did not occur. Consequently, as with the G. aparine, delayed autumn control would be unlikely to jeopardize yields. Thus, if herbicide-tolerant crops are commercialized in Europe, there will be flexibility in timing of application of herbicides to control broad-leaved weeds in winter rape but there would be a risk of yield loss from delayed control of volunteer cereals.
Nitrogen distribution in four grain legumes
Authors: AYAZ S. , McKENZIE B. A. , HILL G. D. , McNEIL D. L.
Published: December 2004

The partitioning of above ground nitrogen (N) in chickpea (Cicer arietinum), lentil (Lens culinaris), lupin (Lupinus angustifolius) and pea (Pisum sativum) at crop maturity was investigated. The plants were grown at different plant populations and sowing depths in 1998/99 and 1999/2000 in Canterbury, New Zealand. In all four legumes the N concentration was highest in seed (29–36 mg/g N) followed by senescent leaves. The lowest N concentration was in stems. Lupin had the highest seed N yield at 16·82 and 19·29 g/m2 followed by chickpea at 10·26 and 13·10 g/m2, in 1998/99 and 1999/2000, respectively. Lentil had the lowest N concentrations and yield. The distribution of N to all legume plant parts increased as population increased up to twice the optimum and 400 plants/m2 in 1998/99 and 1999/2000, respectively. Over all plant populations, the nitrogen harvest index (NHI) was stable in each of the four species across the two seasons. However, the NHI changed with changes in plant population and sowing depth. The N accumulation efficiency (EN) was highest in lentil at 0·024 and 0·027 g N/g DM and lowest in chickpea at 0·018 and 0·021 g N/g DM in 1998/99 and 1999/2000, respectively. The NHI and the crop harvest index (CHI) were correlated and both were strongly associated with seed yield. Thus, NHI might be useful as a selection criterion to improve seed yield in grain legumes.
The economic impact of cow genetic potential for milk production and concentrate supplementation level on the profitability of pasture based systems under different EU milk quota scenarios
Authors: SHALLOO L. , KENNEDY J. , WALLACE M. , RATH M. , DILLON P.
Published: December 2004

A 3-year study was set up to evaluate the influence of cow genetic potential for milk production and concentrate supplementation level on profitability of pasture based systems of milk production. In each of the 3 years, 96 cows were used in a three (genotype)×3 (levels of concentrate supplementation) randomized block design. Cows were categorized based on their pedigree index (PD) for milk production (PDMILK) into low (LP; PDMILK less than 100 kg), medium (MP; PDMILK 100–200 kg) and high (HP; PDMILK 200–300 kg). Concentrate supplementation levels were 376, 810 and 1540 kg per cow per lactation, identified as low (LC), medium (MC) and high (HC) concentrate respectively. Three milk production scenarios were investigated using the Moorepark Dairy Systems Model (MDSM) which included: EU milk quota applied at farm level with current costs and prices (S1), EU quota applied at farm level with projected future costs and prices (S2), and EU milk quota applied at industry level (quota purchasing possible) with projected future costs and prices (S3). The effect of variation in milk price, concentrate price and opportunity cost of land were modelled using stochastic budgeting. The results suggest that where EU milk quota is applied at farm level (S1 and S2), the optimum system of milk production is where margin per unit of output is maximized. When milk quota is applied at industry level (S3) the optimum system will be where margin per cow will be maximized. The results also suggest that the optimum system for cows with lower genetic potential for milk production is low level of concentrate supplementation, while cows with higher genetic potential for milk production is high level of concentrate supplementation.
Quality of genetically modified (GM) and conventional varieties of canola (spring oilseed rape) grown in western Canada, 1996–2001
Authors: DAUN J. K.
Published: December 2004

The success of GM herbicide tolerant canola is demonstrated by its acceptance by the farm community in Canada. There have been continuing comments, however, including some from major customers, suggesting that GM canola has lower quality than conventional canola. Data drawn from both the Western Canada Canola/Rapeseed Co-operative Test data from 1998–2001 and from the Canadian Grain Commission's harvest surveys of canola from 1996–2001 were used to compare the quality of GM and conventional canola registered and grown. Weed seed contamination of harvest survey samples decreased significantly as the herbicide tolerant lines increased in production. While variety registration data suggested GM and conventional lines had no differences in oil content, data from harvest surveys suggested that GM lines tended to have slightly higher oil contents. Protein and oil contents remain inversely related with no differences in the inverse relationship due to GM. While registration requires that all lines have less than 12 micromoles per gram of glucosinolates, data from harvest surveys show GM lines to have significantly less glucosinolates than conventional lines, possibly due to decreased contamination with cruciferous weeds. A comparison of glucosinolate contents between non-GM herbicide tolerant canola and conventional non-herbicide tolerant canola showed similar differences. There were no significant differences in chlorophyll content, erucic acid levels or saturated fatty acids but harvest survey data showed GM lines were slightly more unsaturated than conventional lines. It would seem safe to conclude that differences in quality between GM and conventional canola are due to the functioning of the GM trait – herbicide tolerance – that allows the GM canola to perform to its potential in the field.