bluuebunny/crossref_metadata_2025 huggingface dataset:
Coordination Points: A Hidden Factor in Reconciling Work and Family Life
Authors: SKINNER CHRISTINE
Published: December 2004

Despite improvements in childcare provision since the implementation of the National Childcare Strategy in England in 1998, little is known about the practicalities of managing childcare and employment from a parental perspective. It is not recognised that dependent children have to be physically transported from home to the place of care-education, and if transported by the parent the latter usually also has to travel to their workplace in a different location. This article discusses the complexity involved in coordinating these events, the barriers posed to maternal employment, and the strategies used by working parents to overcome the difficulties. It presents an analysis of qualitative data from in-depth interviews with 40 mothers in a middle-sized city in England. The analysis exposes the additional work involved in temporally, spatially and physically coordinating childcare, education and work. It indicates that early education related to children's ages might have a greater influence on coordination difficulties, and therefore maternal employment, than the numbers of children in a family per se. The article argues that policy makers need to have a greater regard for the time and space dimensions attached to coordination, the coordination support provided by fathers and others (as opposed to childcare), transport issues and the need for fully integrated early years provision in all neighbourhoods.
Inhibition of the elicitation phase of contact hypersensitivity by thymidine dinucleotides is in part mediated by increased expression of interleukin‐10 in human keratinocytes
Authors: Curiel‐Lewandrowski Clara , Venna Suraj S. , Eller Mark S. , Cruikshank William , Dougherty Irene , Cruz Ponciano D. , Gilchrest Barbara A.
Published: December 2004

Abstract: The production of immunomodulatory cytokines such as interleukin‐10 (IL‐10) from keratinocytes and other target cells in the skin plays a crucial role in UV‐induced immunosuppression. Substantial evidence supports an association between DNA damage and immunomodulation. It is also known that small DNA fragments such as thymidine dinucleotides (pTpT) can mimic several UV‐induced effects, including inhibition of the induction phase of the contact hypersensitivity response and up‐regulation of tumor necrosis factor‐alpha (TNF‐α). To determine whether pTpT also induces IL‐10 secretion by keratinocytes, and by inference whether IL‐10 production after UV irradiation is a response to DNA damage, we compared the effects of pTpT with those of UV irradiation on primary human keratinocyte cultures. Subconfluent cultures of primary human keratinocytes were treated either with 10 µM or 100 µM pTpT or diluent alone, or exposed to solar‐simulated light (100 J/m2 of UVB) or sham irradiated. An increase in IL‐10 mRNA expression was observed 6–24 h after irradiation and at 24–48 h after treatment with pTpT. Detection of secreted IL‐10 protein coincided with up‐regulation of IL‐10 gene expression at 48 and 72 h as determined by ELISA. Conditioned media from human keratinocytes treated with pTpT, like that from irradiated cells, significantly inhibited lymphocyte proliferation in the allogeneic‐mixed lymphocyte reaction (MLR) assay. To determine whether pTpT mimics the suppressive influence of UVB on the elicitation phase of contact hypersensitivity, believed to result largely from IL‐10 release, we compared the effects of topical application of pTpT with those of UVB irradiation on C57Bl/6 mice sensitized with dinitrofluorobenzene. Sensitized mice treated with pTpT or UVB irradiation showed markedly suppressed elicitation of ear‐swelling responses. These results demonstrate that increased keratinocyte IL‐10 mRNA level and IL‐10 protein release are among the effects of pTpT and support the hypothesis that pTpT treatment triggers many of the biologic effects of UV irradiation by mimicking UV‐induced DNA damage. Finally, regardless of mechanism, the data suggest that topical treatment with pTpT may provide a novel means of suppressing contact hypersensitivity or other lymphocyte‐mediated reactions in skin.
Differences in motility pattern between human buccal fibroblasts and periodontal and skin fibroblasts
Authors: Lepekhin Eugene , Grøn Birgitte , Berezin Vladimir , Bock Elisabeth , Dabelsteen Erik
Published: December 2004

Migration of fibroblasts from surrounding normal tissue into the wound bed is an important requirement for successful wound healing. This study investigated the motility pattern of buccal, periodontal and skin fibroblasts to determine whether differences in the wound healing efficiency at these sites can be explained by differences in the motile behavior of their respective fibroblast populations. The migratory characteristics were studied in a two‐dimensional culture system. The migration of single cells was time‐lapse video recorded at intervals of 15 min for a period of 6 h using a computer‐assisted microscope work‐station. For evaluation of cell morphology, cell contours were recognized semiautomatically and used for determination of cell area, cell spreading and number and length of processes. We found that the cellular displacement of the buccal fibroblasts was only approximately 50% of the cellular displacement of periodontal and skin fibroblasts. The decreased cellular displacement of the buccal fibroblasts was found to be due to both lower cellular speed and less persistence in direction. The buccal fibroblasts also displayed smaller areas and longer processes. The differences in cellular morphology and motility pattern amongst the three fibroblast types could not be explained by differences in secretion of extracellular matrix components and are therefore believed to reflect phenotypic differences amongst fibroblast subpopulations.
The assessment of systematic reviews in dentistry
Authors: Glenny A. M. , Esposito M. , Coulthard P. , Worthington H. V.
Published: December 2004

The aim of this study was to assess the quality of systematic reviews of effectiveness of interventions in dentistry. The Database of Abstracts of Reviews of Effectiveness and the Cochrane Database of Systematic Reviews were searched to identify systematic reviews examining the effectiveness of interventions for oral, dental and craniofacial disorders and diseases. Sixty‐five reviews were identified and assessed independently by two reviewers. The area most frequently evaluated within the reviews was pain relief/prevention (20/65, 31%) followed by caries and oral medicine. The quality assessment of the identified systematic reviews highlighted key areas where improvements could be made. One major weakness of the reviews was that the search strategies employed were not always adequate. Only 12 reviews (19%) demonstrated an attempt to identify all relevant studies. Other areas of weakness include the screening and quality assessment of primary studies, the pooling of data and examination of heterogeneity, and the interpretation of findings. This investigation shows that the quality of systematic reviews in dentistry could be improved. If future clinical decisions are to be based upon systematic reviews, it is imperative that the reviews address clinically relevant, focused questions and follow a ‘transparent’, well‐designed protocol.
Marginal deterioration as a predictor of failure of a posterior composite
Authors: Hayashi Mikako , Wilson Nairn H. F.
Published: December 2004

The purpose of the present study was to undertake a retrospective analysis of the findings of a multicentre clinical trial to test the hypothesis that marginal deterioration and cavomarginal discoloration may be a predictor of the failure of posterior composite restorations. Longitudinal 5‐yr data from the multicentre trial of Occlusin were analysed (modified USPHS criteria data were available in respect of 1018 of the 1242 restorations included in the study). The 5‐yr failure rate was calculated using three different methods. The various failure rates (maximum 18.8%) and the data pertaining to marginal deterioration and cavomarginal discoloration were then compared and contrasted by means of χ2 test. The analysis revealed that restorations with marginal deterioration at 3 yr were 5.3 times more likely to have failed by 5 yr than restorations with A (Alfa) rated marginal adaptation at 3 yr. Similarly restorations with cavomarginal discoloration at 3 yr were found to be 3.8 times more likely to have failed at 5 yr than restorations with no cavomarginal discoloration at 3 yr. Moreover, restorations with both marginal deterioration and cavomarginal discoloration at 3 yr failed 8.7 times more frequently than restorations with sound margin at 3 yr. It is concluded that clinical investigations of present‐day materials for posterior composite should seek to determine if marginal deterioration and cavomarginal discoloration is an important predictor of the failure of posterior composites, especially when marginal deterioration and cavomarginal discoloration occur simultaneously.
Clinical and SEM evaluation of all‐ceramic chair‐side CAD/CAM‐generated partial crowns
Authors: Bindl Andreas , Mörmann Werner H.
Published: December 2004

The effect of hardware and software on the quality of Cerec all‐ceramic partial crowns was investigated in this cross‐sectional study. Partial crowns (n = 818) had been adhesively placed in 496 patients between 1993 and 1997 using Cerec 1 and Cerec 2 units (groups 1 and 2) as well as Cerec 2 with wall‐spacing software (group 3). From each group, 25 randomly selected partial crowns were evaluated using modified United States Public Health Service (USPHS) criteria. Of these, 12 were randomly selected in each group, replicas taken and examined in a scanning electron microscope for marginal interfacial width and for continuous margin adaptation. Interfacial width of group 1 (308 ± 95 µm) was significantly larger than those of groups 2 (243 ± 48 µm) and 3 (207 ± 63 µm). Continuous margin adaptation at the tooth–luting composite and luting composite–restoration interfaces showed only minor differences in groups 1 (94.5 ± 8% and 95.5 ± 2%), 2 (98.1 ± 1% and 97.5 ± 1.4%) and 3 (96.8 ± 3% and 96.8 ± 2%). Pooled clinical rating was excellent or good at 97% for all groups, indicating acceptable restoration quality except for one breakage in group 1.
Expression profile of matrix metalloproteinases (MMPs) and tissue inhibitors of MMPs in mature human odontoblasts and pulp tissue
Authors: Palosaari Heidi , Pennington Caroline J. , Larmas Markku , Edwards Dylan R. , Tjäderhane Leo , Salo Tuula
Published: December 2004

Previous studies have demonstrated that (at least) matrix metalloproteinase (MMP)‐2, ‐8, ‐9, ‐14 and ‐20 are expressed by human odontoblasts. Here, we analysed the expression of 19 MMPs and their specific tissue inhibitors (TIMP)‐1, ‐2 and ‐3) ‐1, ‐2 and ‐3 in mature human odontoblasts and pulp tissue. Since MMP‐20 is almost exclusively expressed by the dentin–pulp complex cells, we further analysed the effect of transforming growth factor (TGF)‐β1 and bone morphogenetic protein (BMPs)‐2 on its expression. Matrix metalloproteinase‐9 served as a positive control for growth factor responsiveness. It was found that MMP‐1, ‐2, ‐9, ‐10, ‐11, ‐13, ‐14, ‐15, ‐16, ‐17, ‐19, ‐20 and ‐23, in addition to TIMP‐1, ‐2 and ‐3 were expressed by both odontoblasts and pulp tissue. Neither MMP‐3 nor MMP‐12 were expressed in odontoblasts or pulp tissue, and MMP‐7, ‐8, ‐24 and ‐25 were expressed only in the odontoblasts; MMP‐2, ‐10, ‐11, ‐14 and ‐20 were expressed more abundantly by odontoblasts, whereas pulp tissue expressed more MMP‐13 and MMP‐17. Transforming growth factor‐β1 (1 ng ml−1) and BMP‐2 (100 ng ml−1) did not markedly affect MMP‐20 mRNA expression. In contrast, TGF‐β1 alone and with BMP‐2 significantly upregulated MMP‐9 mRNA by 2.4‐fold and by 2.6‐fold, respectively, in odontoblasts, while in pulp tissue no effects could be detected. The wide‐scale expression of MMPs and TIMPs by mature human odontoblasts and pulp tissue suggests that they may participate in dentin matrix organization prior to mineralization, and that growth factors may further control dentin matrix modeling by differentially regulating individual MMPs.
Evaluation of NSAIDs for treating post‐endodontic pain
Authors: Holstein Andrea , Hargreaves Kenneth M. , Niederman Richard
Published: December 2004

Although many studies have evaluated analgesic strategies for control of postendodontic pain, there have been no systematic reviews of this literature. This article describes the process for conducting a systematic review and uses this method to analyze the use of non‐steroidal anti‐inflammatory drugs (NSAIDs) for treatment of postendodontic pain.
Isolation and characterization of a novel cDNA encoding a DNA‐binding protein (Hils1) specifically expressed in testicular haploid germ cells
Authors: Iguchi Naoko , Tanaka Hiromitsu , Yomogida Kentaro , Nishimune Yoshitake
Published: December 2004

A cDNA encoding a protein homologous with histone H1 has been cloned from a haploid germ cell specific cDNA library. Deduced amino acid sequence (170 amino acids) showed 40% identity with histone H1 globular domain. Messenger RNA of the gene was observed exclusively in the testis, and was accumulated after post‐natal day 23. Western blotting analysis showed that the protein encoded by this gene is about 19 kDa in molecular weight, and it was exclusively recovered from the nuclei of testicular germ cells. Immunohistochemical analysis showed that the protein was localized to the nuclei of round and elongating spermatids, consistent with the results of immunoblot analysis. Thus, the gene product was named Hils1 (histone H1 like protein in spermatids 1). In vitro DNA‐binding experiments using DNA‐cellulose mini‐columns showed that Hils1 was able to bind to both double and single stranded‐DNAs in a non‐sequence‐specific manner. These findings suggest that Hils1 may play an important role in the structural changes of spermatid nuclei, such as nuclear condensation, and gene regulation of haploid germ cell differentiation.
Fireflies with or without prespermatophores: Evolutionary origins and life‐history consequences
Authors: Hayashi Fumio , Suzuki Hirobumi
Published: December 2004

During mating, some male North American fireflies produce spermatophores from prespermatophores in their paired reproductive accessory glands. Other species of fireflies have neither prespermatophores nor spermatophores. To establish a pattern of spermatophore occurrence across firefly species, we examined the male internal reproductive system in 20 Japanese species belonging to 10 genera for the presence or absence of prespermatophores. Twelve species from seven genera produced prespermatophores, while eight species from three genera did not. Superimposed on a molecular phylogeny of Japanese fireflies based on mitochondrial 16S ribosomal DNA sequences, the basal group was prespermatophore producers. Prespermatophores appear to have been lost in two different lineages. Species without prespermatophores are characterized by degeneration of both the forewings and hindwings, and by body gigantism in females.
Improved methods for selective dissolution of manganese oxides from soils and rocks
Authors: Neaman A. , Waller B. , Mouélé F. , Trolard F. , Bourrié G.
Published: December 2004

Hydroxylamine hydrochloride (NH2OH‐HCl) and hydrogen peroxide (H2O2) have been used in the past for selective dissolution of manganese oxide minerals. The methods reported, however, give poor recoveries. We tried to improve the methods in this respect. By stoichiometry, incomplete dissolution of Mn oxides is due to the lack of NH2OH‐HCl added or to the lack of acid added in the case of H2O2 treatment. By increasing the amount of solution for a given amount of solid in the case of NH2OH‐HCl and by increasing the acid concentration in the case of H2O2 treatment, we obtained rapid and complete dissolution of synthetic Mn oxides. The dissolution of natural samples, however, was slower than that of synthetic ones. Based on the results obtained, the improved methods are: (i) 0.1 m NH2OH‐HCl, non‐acidified, 2 hours' stirring, and 1 g solid in 2 litres solution; (ii) 30% H2O2 in 0.5 m nitric acid, 0.5 hours' stirring, and 1 g solid in 1 litre solution. The improved methods achieved almost complete release of manganese from samples without decreasing the selectivity of dissolution.
Radio‐labile cadmium and zinc in soils as affected by pH and source of contamination
Authors: Degryse F. , Buekers J. , Smolders E.
Published: December 2004

The determination of radio‐labile metals in soil has gained renewed interest for predicting metal availability. There is little information on to what extent the fraction of labile metal is affected by the soil properties and the source of metal contamination. The radio‐labile content (E value) of Cd and Zn was measured in field‐collected soils with Cd and Zn originating from different sources. The E values were erratic and sometimes even exceeded total metal content when the concentration in the soil extract was less than 8 μg Zn l−1 or less than 3 μg Cd l−1. Addition of EDTA (0.1 mm) to the radio‐labelled soil suspension resulted in larger concentrations of Cd and Zn in solution and smaller E values for these soils. The E values were, however, unaffected by the presence of EDTA (0.1 mm) in soils with larger concentrations of Cd and Zn in solution.

The %E values (E value relative to metal soluble in aqua regia) ranged from 9% to 92% (mean 61%) for Cd and from 3% to 72% (mean 33%) for Zn. No correlation between soil properties and %E was observed for Cd, and the %E of Zn was negatively correlated with soil pH (r = −0.65). There was a strong negative correlation between pH and %E in soils enriched with metals in soluble form (e.g. metal salts, corrosion of galvanized structures). In soils where Cd or Zn were added in a less soluble form, no such correlation was found, and %E values were generally less than in soils spiked with metal salts, suggesting that the source of the contamination controls mainly the labile fractions of Cd and Zn.
Increased frequency of the mannose‐binding lectin LX haplotype in Chinese systemic lupus erythematosus patients
Authors: Huang Y. F. , Wang W. , Han J. Y. , Wu X. W. , Zhang S. T. , Liu C. J. , Hu Q. G. , Xiong P. , Hamvas R. M. J. , Wood N. , Gong F. L. , Bittles A. H.
Published: December 2004

Mannose‐binding lectin (MBL) is an important complement‐activating protein of the human immune system. As a result of one of three structural gene mutations in exon 1 (variants B, C and D) and/or the presence of a low‐efficiency promoter polymorphism, MBL deficiency may be associated with increased susceptibility to infectious diseases and to autoimmune disorders, including systemic lupus erythematosus (SLE). Using a combined approach of heteroduplex generator and polymerase chain reaction, a systematic search for mutations in exon 1 and the promoter region of the MBL gene was performed in a Chinese study population comprising 41 SLE patients and 111 healthy controls. Two alleles, a wild‐type allele A and a variant allele B (a previously reported mutation of GGC to GAC at codon 54), were identified in MBL exon 1. The frequency of the B allele (0.15) was higher in the SLE patients than in the healthy controls (0.09), but the difference did not attain statistical significance (P > 0.05). However, for two polymorphisms at positions −550 and −221 in the promoter region, the frequency of the low‐MBL‐producing haplotype (LX) in the patients (0.2073) was significantly higher than that in the controls (0.0855) (P = 0.003, relative risk = 2.79). Our results suggest that the LX haplotype represents a strong risk factor among Chinese SLE patients. Although of lesser importance, the MBL B allele also may be a risk component in the developing process of SLE in Chinese patients.
Allele frequencies for an interferon‐γ microsatellite in a population of Brazilian leprosy patients
Authors: Reynard M. P. , Turner D. , Junqueira‐Kipnis A. P. , Ramos de Souza M. , Moreno C. , Navarrete C. V.
Published: December 2004

A group of Brazilian leprosy patients and controls were genotyped for a CA‐repeat microsatellite polymorphism within the interferon (IFN)‐γ gene. A significantly higher frequency of alleles 5–7 was observed in this patient population, indicating that IFN‐γ gene polymorphism may contribute to the course of leprosy post‐infection.
HLA‐B*15 subtypes in the population of north‐eastern Thailand
Authors: Romphruk A. , Phongaen K. , Chotechai J. , Puapairoj C. , Leelayuwat C. , Romphruk A. V.
Published: December 2004

The HLA‐B*15 group is the most polymorphic HLA‐B allele and so has several subtypes. These subtypes have not been defined in the population of north‐eastern Thailand (NET). In a previous study, using polymerase chain reaction–sequence‐specific primers (PCR‐SSP), subtypes were categorized into four groups, namely: group I: HLA‐B*15 (01, 04–07, 12, 14, 19, 20, 24, 25, 26N, 27, 32, 33, 34 and 35); group II: HLA‐B*15 (02, 08, 11, 15, 28 and 30); group III: HLA‐B*1503/4802; group IV: HLA‐B*1521. Groups I and II occurred frequently (allele frequency = 8.0 and 2.5%), and thus we optimized the polymerase chain reaction–single‐stranded conformation polymorphism (PCR‐SSCP) method to identify HLA‐B*15 subtypes of groups I and II. Eighty samples of DNA carrying HLA‐B*15 from 300 healthy unrelated individuals were tested. B*1502 (52.5%) and B*1525 (13.8%) were the most common subtypes found in NET. They also showed strong linkage disequilibrium with HLA‐Cw and heterogeneity of HLA‐A, DR, DQ haplotypes. Although limited conclusions can be drawn from this study because of the small number of DNA references used, the baseline data will be useful in the selection of common HLA‐B*15 alleles when subtyping for unrelated donor transplantations.
Determination of exchangeable potassium in soil using ion‐selective electrodes in soil suspensions
Authors: Wang J. J. , Scott A. D.
Published: December 2004

Summary

Methods of determining exchangeable K+of soil by mixing extracting solutions and analysing the soil suspension with ion‐selective electrodes were developed and evaluated on 30 samples of soils. From preliminary comparisons of the K+extracted by BaCl2and NH4OAc solutions and by batch and leaching treatments of soils, we established that suspensions of 5 g soil in 100 ml 0.5 mBaCl2and single batch treatments of 1 h should be used. The exchangeable K+was determined with a K‐selective, valinomycin‐based PVC membrane electrode and electrochemical cells that did or did not include a liquid junction (the reference electrode being a double‐junction reference electrode assembly with a 10 mLiOAc salt bridge solution or a Cl‐selective electrode, respectively). The Ba‐exchangeable K+values were sensibly the same whether a liquid junction was involved or not, a result that can be attributed to the beneficial effects of the salt bridge and the ionic strength of the extractant. Comparisons of these Ba‐exchangeable results with those obtained by various combinations of batch or leaching treatments, BaCl2or NH4OAc extractants and filtrate analysis by the ion‐selective electrode method or atomic absorption spectrometry showed they were all highly correlated (r≥ 0.996). The selectivity of the K+‐selective electrode (kpotKNH4 = 0.004) significantly reduced the interference from indigenous soil NH4+in the BaCl2suspensions. Overall, the results show potentiometric measurements of K+in soil suspensions can provide a simple, rapid, and reliable means of determining exchangeable K+in soils.
Non‐linearity and error in modelling soil processes
Authors: Addiscott T. M. , Tuck G.
Published: December 2004

Error in models and their inputs can be propagated to outputs. This is important for modelling soil processes because soil properties used as parameters commonly contain error in the statistical sense, that is, variation. Model error can be assessed by validation procedures, but tests are needed for the propagation of (statistical) error from input to output. Input error interacts with non‐linearity in the model such that it contributes to the mean of the output as well as its error. This can lead to seriously incorrect results if input error is ignored when a non‐linear model is used, as is demonstrated for the Arrhenius equation. Tests for non‐linearity and error propagation are suggested. The simplest test for non‐linearity is a graph of the output against the input. This can be supplemented if necessary by testing whether the mean of the output changes as the standard deviation of the input increases. The tests for error propagation examine whether error is suppressed or exaggerated as it is propagated through the model and whether changes in the error in one input influence the propagation of another. Applying these tests to a leaching model with rate and capacity parameters showed differences between the parameters, which emphasized that statements about non‐linearity must be for specific inputs and outputs. In particular, simulations of mean annual concentrations of solute in drainage and concentrations on individual days differed greatly in the amount of non‐linearity revealed and in the way error was propagated. This result is interpreted in terms of decoherence.
Soil properties affecting solid–liquid distribution of As(V) in soils
Authors: Brouwere K. De , Smolders E. , Merckx R.
Published: December 2004

The prediction of the mobility of arsenic (As) is crucial for predicting risks in soils contaminated with As. The objective of this study is to predict the distribution of As between solid and solution in soils based on soil properties and the fraction of As in soil that is reversibly adsorbed. We studied adsorption of As(V) in suspensions at radiotrace concentrations for 30 uncontaminated soils (pH 4.4–6.6). The solid–liquid distribution coefficient of As (Kd) varied from 14 to 4430 l kg−1. The logarithm of the concentration of oxalate‐extractable Fe explained 63% of the variation in log Kd; by introducing the logarithm of the concentration of oxalate‐extractable P in the regression model, 85% of the variation in log Kd is explained. Double labelling experiments with 73As(V) and 32P(V) showed that the As to P adsorption selectivity coefficient decreased from 3.1 to 0.2 with increasing degree of P saturation of the amorphous oxides. The addition of As(V) (0–6 mmol kg−1) reduced the Kd of 73As up to 17‐fold, whereas corresponding additions of P(V) had smaller effects. These studies suggest that As(V) is adsorbed to amorphous oxides in soils and that sites of adsorption vary in their selectivity in respect of As and P. The concentration of isotopically exchangeable As in 27 contaminated soils (total As 13–1080 mg kg−1) was between 1.2 and 19% (mean 8.2%) of its total concentration, illustrating that a major fraction of As is fixed. We propose a two‐site model of competitive As(V)–P(V) sorption in which amorphous Fe and Al oxides represent the site capacity and the isotopically exchangeable As represents the adsorbed phase. This model is fitted to 73As adsorption data of uncontaminated soils and explains 69% of the variation of log Kd in these soils. The log Kd in contaminated soils predicted using this two‐site model correlated well with the observed log Kd (r = 0.75). We conclude that solubility of As is related to the available binding sites on amorphous oxides and to the fraction of As that is fixed.
An anion resin membrane technique to overcome detection limits of isotopically exchanged P in P‐sorbing soils
Authors: Maertens E. , Thijs A. , Smolders E. , Degryse F. , Cong P. T. , Merckx R.
Published: December 2004

Isotopically exchanged phosphorus is difficult to determine in soils that strongly sorb P (so that there is little P in solution) and in soils with large concentrations of colloidal P in soil suspensions. A method is proposed in which anion exchange membranes (AEM) are added to the soil suspension after an initial period of isotopic exchange with 32P‐labelled phosphate ions. Isotopically exchanged P, termed EAEM, is calculated from the ratio of labelled phosphate ions to the total phosphate ions on the membrane. The EAEM was compared with the E value measured in an aqueous soil extract (EWater extract) for 14 soils with different degrees of P sorption. The two methods gave similar results in soils with large P concentrations in an aqueous soil extract. However, EWater extract values significantly exceeded the EAEM values by up to 18‐fold when soluble P was near the determination limit (0.008 mg P l−1). In a second experiment, two Ferralsols received further P from inorganic and plant sources and were incubated for 7 days. Treatment effects on labile P were erroneous as detected by the EWater extract but were significant as detected with the AEM method. Third, EAEM values were followed in a Lixisol and a Ferralsol which received labelled phosphate ions with carrier just before the beginning of a 23‐day incubation. The approximate recovery of added inorganic P in the EAEM value suggested that this method adequately samples labile P in P‐sorbing soils. All these results showed that errors in the determination of E values for soils with very small concentrations of P in the soil solution are reduced using the proposed method.
Classification, assessment and trophic reconstruction of Danish lakes using chironomids
Authors: Brodersen Klaus Peter , Lindegaard Claus
Published: December 2004

1. Surface‐sediment assemblages of subfossil chironomid head capsules from fifty‐four primarily shallow and nutrient‐rich Danish lakes were analysed using multivariate numerical techniques. The species data, comprising forty‐one chironomid taxa, were compared to environmental monitoring data in order to establish a relationship between chironomid faunal composition and lake trophic state.

2. The subfossil assemblages were compared to the chironomid bathymetric distributions along transects from four lakes. Correspondence analysis and similarity coefficients showed that the subfossil assemblages, sampled in the lake centre, reflect the chironomid communities in the littoral at a depth of 2–7 m.

3. Two‐way indicator species analysis (TWINSPAN) was used to classify the Danish lakes into five groups defined by trophic state, lake depth and pH. Eighteen chironomid taxa showed significant differences in abundance among the five groups. Canonical correspondence analysis (CCA) showed the chlorophyll a concentration ([Chl a]) and Secchi depth to be the variables best correlated to the faunal data, and fourteen taxa were significantly correlated to [Chl a].

4. The strong correlation between chironomid data and the ln‐transformed ([Chl a]) was used to create a weighted averaging (WA) model to infer lake trophic state. Several models were tested by cross validation (leave‐one‐out jack‐knifing), and a simple WA model using inverse de‐shrinking had a RMSEPjack of 0.65 (ln units) and a r2jack of 0.67.

5. The results can be used in the assessment and reconstruction of lake trophic state for long‐term monitoring and palaeoecological investigations of shallow, temperate lakes in the mesotrophic to hypertrophic nutrient range.
Implications of varying pipe model relationships on Scots Pine growth in different climates
Authors: BERNINGER F. , NIKINMAA E.
Published: December 2004

1. The process‐based model SIMFORG, based on the pipe theory, was parameterized for Scots Pine at six locations along a north–south gradient in Europe. The ratio of foliage mass to stem cross‐sectional area was changed as a function of potential evapotranspiration as proposed by Berninger et al. (1995).

2. Allocation to the stem differed between the locations and affected consequently the stemwood production. Variation in the net primary production and differences in the pipe model parameters were responsible for these differences. There was good agreement between measured and simulated data.

3. Increase in primary production, as predicted by climate‐change senarios, increased allocation to the stem. However, the results were sensitive to changes in the foliage mass to stem sapwood cross‐sectional area ratio. The changes in allocation were higher in the north than in the south.
Carbon and water fluxes in a calcareous grassland under elevated CO2
Authors: STOCKER R. , LEADLEY P. W. , KÖRNER CH.
Published: December 2004

1. As part of a long‐term study of the effects of elevated CO2 on biodiversity and ecosystem function in a calcareous grassland, we measured ecosystem carbon dioxide and water‐vapour fluxes over 24‐h periods during the 1994 and 1995 growing seasons. Data were used to derive CO2 and H2O gas‐exchange response functions to quantum flux density (QFD).

2. The relative increase in net ecosystem CO2 flux (NEC) owing to CO2 enrichment increased as QFD rose. Daytime NEC at high QFD under elevated CO2 increased by 25% to 60%, with the greatest increases in the spring and after mowing in June when above‐ground biomass was lowest. There was much less stimulation of NEC in early June and again in October when the canopy was fully developed. Night‐time NEC was not significantly altered under elevated CO2.

3. Short‐term reversal of CO2 concentrations between treatments after two seasons of CO2 exposure provided evidence for a 50% downward adjustment of NEC expressed per unit above‐ground plant dry weight. However, when expressed on a land area basis, this difference disappeared because of a c. 20% increase in above‐ground biomass under elevated CO2.

4. Ecosystem evapotranspiration (ET) was not significantly altered by elevated CO2 when averaged over all measurement dates and positions. However, ET was reduced 3–18% at high QFD in plots at the top of the slope at our study site. In summary, CO2 enrichment resulted in a large stimulation of ecosystem CO2 capture, especially during periods of a large demand of carbon in relationship to its supply, and resulted in a relatively small and variable effect on ecosystem water consumption.
3D imaging of a reservoir analogue in point bar deposits in the Ferron Sandstone, Utah, using ground‐penetrating radar
Authors: Zeng Xiaoxian , McMechan George A. , Bhattacharya Janok P. , Aiken Carlos L.V. , Xu Xueming , Hammon William S. , Corbeanu Rucsandra M.
Published: December 2004

Most existing reservoir models are based on 2D outcrop studies; 3D aspects are inferred from correlation between wells, and so are inadequately constrained for reservoir simulations. To overcome these deficiencies, we have initiated a multidimensional characterization of reservoir analogues in the Cretaceous Ferron Sandstone in Utah. Detailed sedimentary facies maps of cliff faces define the geometry and distribution of reservoir flow units, barriers and baffles at the outcrop. High‐resolution 2D and 3D ground‐penetrating radar (GPR) images extend these reservoir characteristics into 3D to allow the development of realistic 3D reservoir models. Models use geometric information from mapping and the GPR data, combined with petrophysical data from surface and cliff‐face outcrops, and laboratory analyses of outcrop and core samples.

The site of the field work is Corbula Gulch, on the western flank of the San Rafael Swell, in east‐central Utah. The outcrop consists of an 8–17 m thick sandstone body which contains various sedimentary structures, such as cross‐bedding, inclined stratification and erosional surfaces, which range in scale from less than a metre to hundreds of metres. 3D depth migration of the common‐offset GPR data produces data volumes within which the inclined surfaces and erosional surfaces are visible. Correlation between fluid permeability, clay content, instantaneous frequency and instantaneous amplitude of the GPR data provides estimates of the 3D distribution of fluid permeability and clay content.
The role of the British Library for medical and health information*
Authors:   SCONUL
Published: December 2004

This paper examines the role of the British Library in the provision of medical and health information in the UK. Medicine—in both the public and private sector—is big business. The British Library is already heavily involved in the provision of information to the medical community but there is little planning for the most cost‐effective allocation of resources for medical information across the nation. There is no focus for research and development in medical information policy and medical librarians do not readily identify with the British Library. This paper suggests that the British Library could help to develop a focus for medical information policy in the way the National Library of Medicine does for the USA.
Down regulation of bcl‐2 by p53 in nasopharyngeal carcinoma and lack of detection of its specific t(14;18) chromosomal translocation in fixed tissues
Authors: HARN H‐J. , HO L‐I. , LIU C‐A. , LIU G‐C. , LIN F‐G. , LIN J‐J. , CHANG J‐Y. , LEE W‐H.
Published: December 2004

High levels of bcl‐2 protein have been found in a wide variety of human cancers. Since p53 gene inactivation occurs in over half of human cancers, it is possible that loss of p53‐mediated repression of bcl‐2 gene expression accounts, at least in part, for the frequent abnormalities in bcl‐2 protein production seen in tumours. By using immunohistochemical methods, we have analysed thirty‐three nasopharyngeal carcinomas for p53 and bcl‐2 expression. We found an inverse correlation between the expression of these two proteins (P < 0.001). Moreover, we utilized universal oligonucelotide primers of a region 5′ to the bcl‐2 MBR and at the 3′ end of JH segments to initiate a DNA polymerase chain reaction that amplified these bcl‐2‐JH junctures. Of the twelve nasopharyngeal carcinomas expressing bcl‐2, none showed a t(14;18) chromosome translocation. These findings may indicate potential mechanisms by which bcl‐2 regulates apoptosis.
Hyalinizing trabecular carcinoma of thyroid gland
Authors: McCLUGGAGE W.G. , SLOAN J.M.
Published: December 2004

We describe two cases of encapsulated thyroid tumours which displayed the classic morphological features of hyalinizing trabecular adenoma. In addition, both were characterized by focal invasion of the capsule and of thin‐walled capsular blood vessels. Positive immunohistochemical staining of tumour cells for thyroglobulin and negative staining for calcitonin, chromogranin and CEA allowed distinction from medullary carcinoma. Electronmicroscopy revealed groups of tumour cells, surrounded by abundant basement membrane type material. Occasional tumour cells contained abundant cytoplasmic intermediate filaments. A flow cytometric analysis revealed one tumour to have a diploid DNA pattern and the other to be DNA aneuploid. These cases illustrate that a malignant variant of hyalinizing trabecular adenoma, namely hyalinizing trabecular carcinoma, exists. Hyalinizing trabecular tumours of the thyroid should not be considered uniformly benign lesions. As with follicular neoplasms, multiple sections from the capsule should be examined histologically in order to assess the presence or absence of capsular and/or vascular invasion.
‘Undifferentiated progenitor cells’ in focal nodular hyperplasia of the liver
Authors: Roskams T. , De Vos R. , Desmet V.
Published: December 2004

Focal nodular hyperplasia is a tumour like lesion, characterized by a central fibrous scar with irradiating fibrous septa that surround hyperplastic nodules and contain multiple bile ductules. The origin of the bile ductular structures is not clear. Recently, we found evidence for the existence of human counterparts of rat oval cells (potential stem cells) that have the ability of differentiating towards both bile duct cells and hepatocytes. These cells were found in regenerating human liver as well as in chronic cholestatic conditions. Because cholestatic features are seen in focal nodular hyperplasia, we initiated an immunohistochemical study on 23 surgical specimens using antibodies specific for cytokeratins 7 and 19 (bile duct type cytokeratins), OV6 (rat oval cell marker), chromogranin‐A (shown to be positive in reactive bile ductules and human oval‐like cells) and neural cell adhesion molecule—NCAM (shown to be positive in reactive bile ductules) to investigate whether ‘undifferentiated progenitor cells’ are also present in focal nodular hyperplasia. Electronmicroscopy was applied in five cases. Bile ductules invariably showed immunoreactivity for CK7 and 19, OV6, chromogranin‐A and NCAM. In addition, small individual cells with an oval nucleus and a small rim of cytoplasm, in the vicinity of the septa, were immunoreactive for chromogranin‐A, CK7 and 19 and OV6. These cells were hardly recognizable on routine light microscopy. Clusters of periseptal hepatocytes, seemingly in continuity with bile ductular structures, had a transitional phenotype: they stained positive for chromogranin‐A, CK7 and OV6 and sometimes formed liver cell rosettes. The number of OV6‐positive hepatocytes was greater than the number of chromogranin‐A and CK7 positive hepatocytes. This indicates that, in human liver, OV‐6 is not purely a marker of progenitor cells. Ultrastructurally, small immature cells, highly resembling rat oval cells, were recognized in the vicinity of septa. In addition, transitional cells displaying characteristics both of hepatocytes and bile duct cells were also present. These results confirm the presence of ‘undifferentiated progenitor cells’ in focal nodular hyperplasia and suggest that the ductular reaction in these lesions results, at least partly, from activation of these cells.
Comparison of apical leakage shown by four different dyes with two evaluating methods
Authors: Tamse  , Katz  , Kablan
Published: December 2004

A study was conducted in vitro to assess and compare the extent of apical leakage of four dyes by two commonly‐used evaluation methods. For the study, 120 single‐rooted extracted teeth were prepared by the step‐back technique and obturated by lateral condensation with gutta‐percha and Roth 801 sealer. After randomly allocating the roots into six groups, they were immediately immersed in dye for 72 h, using vacuum for 30 min at 40°C. Teeth were immersed in Eosin, Methylene Blue, Black India Ink and Procion Brilliant Blue and cross‐sectioned in 0.7 mm thick slices. Those immersed in Black India Ink and Procion Brilliant Blue were also evaluated by the clearing process. Dye penetration was assessed using a stereomicroscope. A statistically significant greater dye penetration was measured in the cross‐sectioned group compared to the clearing group using the same dyes (Black India Ink, P= 0.020, Procion Brilliant Blue, P= 0.040). In the cross‐section groups, no statistical significant difference was observed in the amount of leakage comparing the four dyes. No statistically significant difference was found in the leakage pattern of Procion Brilliant Blue and Black India Ink using the clearing technique (P= 0.797). The evaluating method (cross‐sections versus clearing) rather than the dye properties was the main difference between results. More research is needed to standardize dye leakage studies.
Telephone hotline assessment and counselling of suicidal military service veterans in the USA
Authors: Porter Luz S. , Astacio Marcial , Sobong Loreto C.
Published: December 2004

Studies show that suicide occurs more frequently among people who are elderly, male, single, divorced or widowed, alienated, and among those with a life‐threatening illness. Military service veterans are not spared these conditions; in some respect, they represent the ‘down and out’, the lonely and, increasingly, the older isolated people. This correlational descriptive study sought to identify the characteristic profile of telephone hotline users among veterans, their triggering crisis events, and whether the methods commonly used in suicide attempts relate to certain types of crisis. The random sample consisted of 271 veterans of the US military service, ranging in age from 20 to 79 years. Data were collected from nursing notes documented in the hotline suicide telephone call assessment records. The findings portray a sociodemographic profile of military veterans at risk of suicide attempts. Loneliness, alcoholism and unemployment topped the list of triggering events. The most common method used was drug overdose; shooting was a close second. These findings could serve as a base for development of suicide‐prevention‐focused programmes and optimal use of telephone hotlines for assessment and timely intervention of persons in great crisis.
Compathy: the contagion of physical distress
Authors: Morse Janice M. , Mitcham Carl
Published: December 2004

A qualitative study examining the nurse–patient relationship has identified the contagion of physical distress or ‘compathy’ as a significant but otherwise neglected phenomenon. Compathy occurs when one person observes another person suffering a disease or injury and experiences in one's physical body a similar or related distress. Thus, compathy is the physical equivalent to empathy. Although the contagion of physiological (compathetic) responses has been previously documented (for example, as couvades or psychogenic epidemics of the workplace), it has not been theoretically explicated. Triggers for the compathetic response are identified and include observing the suffering, hearing, or reading—or even thinking about—descriptions of the symptoms. The relevance of the compathetic response in the caregiving relationship and the necessity of suppressing the response when inflicting pain as a part of providing therapy are described. The concept of compathy is analysed and defended.
Sampling hard to reach populations
Authors: Faugier Jean , Sargeant Mary
Published: December 2004

Studies on ‘hidden populations’, such as homeless people, prostitutes and drug addicts, raise a number of specific methodological questions usually absent from research involving known populations and less sensitive subjects. This paper examines the advantages and limitations of nonrandom methods of data collection such as snowball sampling. It reviews the currently available literature on sampling hard to reach populations and highlights the dearth of material currently available on this subject. The paper also assesses the potential for using these methods in nursing research. The sampling methodology used by Faugier (1996) in her study of prostitutes, HIV and drugs is used as a current example within this context.
Assessing quality in health care services: lessons from mental health nursing
Authors: Shaw Ian
Published: December 2004

Quality in health care services is neither a simple nor an apolitical issue. Quality is a complex concept and how it is defined and measured has important consequences for services. The definition and measurement of service quality in health care has slipped from professional toward managerial control. Professionals such as nurses have an absolute concept of quality which is a part of their value system and based upon their training and experience. Managerial concepts of quality may be influenced by other organizational concerns such as the pursuit of efficiency. This paper outlines quality assurance systems in mental health nursing and the wider quality debate and argues that there may well be a trade‐off between quality of service and efficiency. The moves toward outcome measures and performance indicators are also discussed and the argument forwarded that such a focus serves to exclude users and cloaks serious issues in service delivery. The argument of this paper is that evaluation of service quality needs to include users, and this could provide them with a platform for enhanced involvement in service planning.
Decision‐making and paediatric pain: a review
Authors: Abu‐Saad Huda Huijer , Hamers Jan P.H.
Published: December 2004

The aim of this paper is to present an overview of the literature on the factors influencing decision‐making the nursing care of children in pain. To that effect published and unpublished references werr reviewed. The most frequently cited factors influencing the assessment and management of pain in children are summarized and discussed. Finally recommendations are made where further research is warranted.