bluuebunny/crossref_metadata_2025 huggingface dataset:
Guild structure of wood‐rotting fungi based on volume and decay stage of coarse woody debris
Authors: Takahashi Kazuo H. , Kagaya Takashi
Published: December 2004

Wood‐rotting fungi are major organisms exploiting coarse woody debris (CWD) in forests. Here, guild structure of wood‐rotting fungi was investigated in cool temperate (Chichibu) and warm temperate (Chiba) forests in central Japan, based on their occurrence on CWD of different volumes and decay stages. Analysis with the program partitioning around medoids (PAM) recognized two clusters in Chichibu and four in Chiba, and their silhouette coefficients (an index for reliability of clustering) were adequately high, suggesting the existence of non‐random clustering structure. To examine whether the clustering structure observed in this study was based on fungal preference for CWD or discontinuities in the distribution of CWD characteristics (decay stage and volume), null model analyses were made in which all fungal species were randomly redistributed among CWD. Silhouette coefficients based on the null model were reasonably high in both localities, indicating the observed clustering structure was at least partly attributable to the discontinuity in the distribution of CWD characteristics. In addition, the silhouette coefficient of the observed clustering structure was significantly higher than that of the null model in both localities. This result suggests that guild structure was present in the wood‐rotting fungal communities, and the difference in CWD preference among wood‐rotting fungi contributed to the structuralization of the communities.
Oestrogen receptor beta is the predominant oestrogen receptor in human scalp skin
Authors: Thornton M. J. , Taylor A. H. , Mulligan K. , Al‐Azzawi F. , Lyon C. C. , O'Driscoll J. , Messenger A. G.
Published: December 2004

Abstract: Oestrogens play a major role in non‐classic target tissues in both sexes, yet there have been few studies on estrogens and skin. Recently a second oestrogen receptor (ERβ) has been discovered. Therefore, we have compared the expression of oestrogen receptor alpha (ERα), beta (ERβ), the androgen receptor (AR) and a cell proliferation marker in male and female non‐balding scalp skin. ERβ was the major steroid receptor expressed in human skin. It was highly expressed in epidermis, blood vessels and dermal fibroblasts, in contrast to ERα and AR. In the hair follicle, ERβ expression was localized to nuclei of outer root sheath, epithelial matrix and dermal papilla cells, in contrast to ERα, and the AR, which was only expressed in dermal papilla cells. Serial sections also showed strong nuclear expression of ERβ in the cells of the bulge, while neither ERα nor AR was expressed. In the sebaceous gland, ERβ was expressed in both basal and partially differentiated sebocytes. ERα exhibited a similar pattern of expression, while the AR was expressed in the basal and very early differentiated sebocytes. There was no obvious difference in the expression of either oestrogen receptor in male or female skin. The wide distribution of ERβ in human skin suggests that oestrogens may play an important role in the maintenance of skin and in the regulation of the pilosebaceous unit, and provides further evidence for oestrogen action in non‐classic target tissues. The differential expression of ERα, ERβ and AR in human skin suggests that the mechanisms by which steroid hormones mediate their effects may be more complex than previously thought.
Divergent effects of two sequence variants of GJB3 (G12D and R32W) on the function of connexin 31 in vitro
Authors: Rouan F. , Lo C. W. , Fertala A. , Wahl M. , Jost M. , Rodeck U. , Uitto J. , Richard G.
Published: December 2004

Abstract: Recently, we identified several missense mutations of the connexin gene GJB3 encoding connexin 31 (Cx31) in erythrokeratodermia variabilis (EKV), an autosomal dominant skin disorder. These mutations include G12D, which replaces a conserved glycine residue in the amino‐terminus of Cx31 and is associated with a severe EKV phenotype. In contrast, the biologic relevance of the GJB3 sequence variant R32W located in the first transmembrane domain of Cx31 is disputed. To examine the effects of these sequence variants on Cx31 biogenesis and gap junction activity we expressed wild type and mutant Cx31‐Flag constructs in HeLa cells. Using immunostaining, all expression variants were detected in the cytoplasm and in a punctate pattern at the cell surface, indicating that G12D and R32W did not interfere with either protein synthesis or transport to the cell membrane. Similarly, oligomerization into hemichannels appeared not impaired when expressing either Cx31 mutant as assessed by size exclusion chromatography, immunoblotting and immunostaining. However, dye transfer experiments and monitoring of intracellular calcium levels in response to serum stimulation revealed that G12D‐Cx31 did not form functional gap junction channels, probably due to incorrect assembly or altered properties of Cx31 channels. In contrast, intercellular coupling between cells expressing R32W‐Cx31 was comparable to that of wtCx31, suggesting that R32W is a functionally inconsequential polymorphism of Cx31.
Impact of caries experience in the deciduous molars on the emergence of the successors
Authors: Leroy Roos , Bogaerts Kris , Lesaffre Emmanuel , Declerck Dominique
Published: December 2004

The purpose of this study was to evaluate the effect of caries experience in a primary molar (decayed and/or restored vs. extracted) on the timing of emergence of its successor. Data were obtained from a longitudinal epidemiological study in a sample of 4468 Flemish children. Survival analyses with log‐logistic distribution were performed to calculate median emergence ages and 95% confidence intervals (CI); caries experience was added as a covariate. The results indicate that the emergence of the maxillary and mandibular premolars was accelerated by 2–8 months when its predecessor had been decayed and or restored but had not been extracted. Premature loss of maxillary primary molars resulted in a significant acceleration of the emergence of the premolars; this was not observed in the mandible. In conclusion, when considering permanent tooth emergence ages, caries experience in the primary dentition should be taken into account.
The effect of retention on orthodontic relapse after the use of small continuous or discontinuous forces. An experimental study in beagle dogs
Authors: Van Leeuwen Eric J. , Maltha Jaap C. , Kuijpers‐Jagtman Anne M. , Van’t Hof Martin A.
Published: December 2004

Relapse is a major concern in orthodontics for which avoidance retention is the general procedure. However, the effect of retention on relapse after active tooth movement with different force regimes has never been studied in a standardized experimental setting. Mandibular third premolars were extracted in 19 young adult beagle dogs. Three months later, the second premolars were bodily moved distally with forces of 10 cN or 25 cN. The forces were applied for 24 h d−1 or for 16 h d−1. After 4 months, relapse was allowed in half of the animals, while in the others relapse was preceded by retention for 90 d. Statistical analyses were performed on the relation between force regime, active tooth movement, retention, and relapse. Force magnitude had no effect on relapse, while continuous forces resulted in a longer‐lasting and more pronounced relapse than did discontinuous forces. A significant positive correlation was found between the amount of active tooth movement and both the rate and the total amount of relapse, but not between the amount of active tooth movement and the duration of the relapse. Retention had no effect on the duration of the relapse, but it strongly decreased its total amount. Finally, the effect of retention on the amount of relapse was strongly correlated with the amount of active tooth movement.
COX‐2 inhibitors for endodontic pain
Authors: Khan Asma A. , Dionne Raymond A.
Published: December 2004

The recent introduction of non‐steroidal anti‐inflammatory drugs (NSAIDs) that selectively inhibit cyclooxygenase‐2 (COX‐2), has generated considerable enthusiasm as a potential class of analgesic drugs with reduced side‐effect liability. This article reviews the pharmacology of the COX‐2 inhibitors from the perspective of their potential role in the management of the endodontic pain patient.
Are antibiotics effective for endodontic pain?
Authors: Fouad Ashraf F.
Published: December 2004

Although antibiotics are frequently prescribed to treat endodontic pain patients, there is little evidence from the clinical literature to support this indication. This review focuses on the clinical evidence regarding the efficacy of antibiotics for treating postendodontic pain.
Effect of Medical Conditions on Improvement in Self‐Reported and Observed Functional Performance of Elders*
Authors: Miller Ram R. , Zhang Yuqing , Silliman Rebecca A. , Hayes Margaret Kelly , G. leveille Suzanne , Murabito Joanne M. , Kiel Douglas , O'connor George T. , Felson David T.
Published: December 2004

Objectives: To evaluate the effect of nine disabling medical conditions upon recovery from functional limitations by elders.

Design: Retrospective analysis of prospective longitudinal cohort.

Setting: Community.

Participants: Persons aged 65 and older in Framingham Heart Study.

Measurements: Change in function in elders from biennial Examinations 18 (1983–85; baseline) through 23 (1994–96). At each examination, subjects reported limitations in heavy household work, walking up and down stairs, walking half a mile, bathing, toileting, and continence. They were also directly observed for performance of transferring in and out of a chair, dressing, walking 50 feet, and carrying a 10‐pound object 10 feet. The prevalence of functional limitations and the incidence of recovery from functional limitation by the subsequent examination for each task were calculated. The effects of congestive heart failure, cognitive impairment, diabetes mellitus, stroke, depressive symptoms, hip fracture, knee pain, claudication, and chronic obstructive pulmonary disease were evaluated. The relationship between the total number of comorbid conditions present (0, 1, 2, 3 or more), the presence of each individual condition at the start of each examination cycle, and the incidence of recovery from functional limitations were examined using generalized estimating equations.

Results: One thousand eight hundred twenty‐five subjects were studied at baseline; 1,026 were available 10 years later. Mean age of subjects at baseline was 73.5 (range 61–95); 60.7% were women. The prevalence of functional limitations ranged from 3.1% to 29.8% at biennial Examination 18 and increased to 15.1% to 32.4% at Examination 23. The incidence of recovery ranged from 3.2% to 78.4% depending upon the task and the examination cycle. Increasing disease burden, as measured by the number of comorbidities, was associated with a decreased likelihood of recovery from functional limitations. Diabetes mellitus, stroke, depressive symptoms, hip fracture, and knee pain had the strongest adverse effect upon recovery from functional limitations.

Conclusion: In these community‐dwelling elders, recovery from prevalent functional limitations was frequent. Increasing disease burden was associated with a decreased incidence of recovery. Diabetes mellitus, stroke, depressive symptoms, hip fracture, and knee pain had the strongest adverse effect on recovery from functional limitations.
Anthomyzidae (Diptera: Acalyptrata) from Japan and adjacent areas
Authors: Sueyoshi Masahiro , Roháček Jindrich
Published: December 2004

Anthomyzidae from Japan are revised and keyed, and additional information on anthomyzid fauna of adjacent areas is provided. Nine species in four genera are recognized: five of the species, Amygdalops nigrinotum, Anthomyza drachma, An. flavosterna, An. trifurca and Ischnomyia triarmigera, are described as new to science, and the other four, An. bellatrix Roháček, An. elbergi Andersson, An. macra Czerny and Stiphrosoma fissum Roháček, are newly recorded from Japan. The genus Ischnomyia Loew is new to the Old World, and the female Anthomyza bellatrix is described for the first time.
Chemical fractionation to characterize changes in sulphur and carbon in soil caused by management
Authors: Bhupinderpal‐Singh  , Hedley M.J. , Saggar S. , Francis G.S.
Published: December 2004

Classical chemical fractionation of soil sulphur (S) into HI‐reducible S and carbon‐bonded S does not separate S in soil into fractions that have differing mineralization potentials. Other techniques are needed to separate organic S into more labile and less labile fractions of biological significance, irrespective of their bonding relations. We have sequentially fractionated soil S and carbon (C) into their ionic forms released onto ion‐exchange resins and organic S and C extracted in alkali of increasing concentration. We evaluated the technique on pasture and arable soils that had received various fertilizer and cultivation treatments. Total S and C were greater in the soil of the fertilized pasture than in that of the unfertilized pastures. Continuous arable cropping decreased total soil S and C, whereas restoration to pasture caused an accumulation.

Resin, 0.1 m NaOH, 1 m NaOH and residual fractions accounted for between 1–13%, 49–69%, 4–16% and 19–38% of total soil S and between 5–6%, 38–48%, 5–7% and 46–53% of total soil C, respectively. Among different S and C fractions, the size of the 0.1 m NaOH and residual fractions changed more with the change in land use and management. The 0.1 m NaOH fraction had a narrower C:S ratio (50–75:1) than did the residual fraction (96–141:1). The significant degree of change in these two fractions, caused by differences in land management, indicates that they may be useful indicators of change in ‘soil quality’.
HLA‐DPB1*0401 is associated with dominant protection against type 1 diabetes in the general Saudi population and in subjects with a high‐risk DR/DQ haplotype
Authors: Al‐Hussein K. A. , Rama N. R. , Ahmad M. , Rozemuller E. , Tilanus M. G.
Published: December 2004

The human leukocyte antigen (HLA) class II DQB1*0201/0202‐DRB1*04 genotype has been identified as predisposing to type 1 diabetes [insulin‐dependent diabetes mellitus (IDDM)] in the Saudi Arabian population (P = 0.0002; odds ratio = 0.67; 95% confidence interval = 0.009–0.381). In this study, we searched for a factor at the DPB1 locus by analysing DPB1 polymorphism using sequence‐based typing in 86 Saudi IDDM patients and control subjects, all carrying the HLA‐DRB1*04/DQB1*02 haplotype or the known susceptibility allele DQB1*0201/0202. Significant protection was conferred by DPB1*0401, which was observed in 17 of 50 control subjects (55%) and 2 of 36 IDDM patients (5%) with the DQB1*0201/0202 allele (P = 0.0012; odds ratio = 8.75; confidence interval = 1.72–59.70). Our data showing a high frequency of the DPB1*0401 allele even in the presence of the predisposing DQB1*02 allele in healthy subjects may indicate a protective effect of this combination of HLA alleles against type 1 diabetes. This finding supports the hypothesis that protective HLA class II genes can override the risk conferred by HLA‐DQ susceptibility alleles. Further studies using larger cohorts of control subjects and patients should be undertaken to confirm this observation.
Levels of soluble HLA‐G in amniotic fluid are related to the sex of the offspring
Authors: Emmer P. M. , Steegers E. A. P. , Van Lierop M. J. , Loke Y. W. , Van Der Meer A. , Joosten I.
Published: December 2004

Although HLA‐G is thought to play a modulatory role in the immune system, its function and expression require to be elucidated. We analysed soluble HLA‐G levels in mid‐trimester amniotic fluid (n = 64) from uncomplicated pregnancies. We found a decrease in soluble HLA‐G levels for female offspring as compared to male offspring (P < 0.007). This may be a consequence of the immuno‐modulatory capacity of HLA‐G.
Sorption of iron‐cyanide complexes on goethite
Authors: Rennert T. , Mansfeldt T.
Published: December 2004

Iron‐cyanide complexes are present in soils on sites of former gas plants and coke ovens. We have studied the sorption of the complexes ferricyanide, [Fe(CN)6]3–, and ferrocyanide, [Fe(CN)6]4–, on goethite in batch experiments, including the effects of concentration, time, ionic strength, pH, and the extent of reversibility. The sorption of ferricyanide showed features of both outer‐sphere and inner‐sphere complexation: its extent decreased with increasing pH; it depended on ionic strength; it was quickly and completely reversible; and it induced a change in surface electric potential. In contrast, sorption of ferrocyanide depended on pH to a lesser extent and was not affected by ionic strength at different pHs. The desorption was slower and incomplete. For ferrocyanide we conclude that sorption involves inner‐sphere complexation and precipitation of a Berlin‐Blue‐like phase on the goethite surface.
Availability and speciation of cadmium added to a calcareous soil under various managements
Authors: Renella G. , Adamo P. , Bianco M. R. , Landi L. , Violante P. , Nannipieri P.
Published: December 2004

Potential risks for human health and adverse effects on soil quality caused by accumulation of cadmium (Cd) in soil at concentrations around or exceeding current European Union (EU) permitted limits have long been recognized. We have assessed availability and partitioning of Cd in a Mediterranean calcareous soil under four management regimes. Cadmium was added as a single pulse of CdSO4at the maximum Cd concentration established by the EU for sludge‐amended agricultural soils and concentrations exceeding the mandatory limits. Soils were treated with 0, 3, 10 and 50 mg Cd kg−1soil, incubated moist and analysed at selected times up to 600 days. Cadmium availability and distribution in soil were studied by neutral electrolyte and sequential extractions. During the incubation, the availability of Cd was not strictly dependent on the amount of metal added as the exchangeable fractions were similar shortly after the additions of Cd regardless of its initial concentration. Sequential extractions showed that for concentrations of 3 and 10 mg Cd kg−1soil Cd was evenly distributed among the soil phases, and its mobility was reduced mainly by adsorption on carbonates. At Cd concentrations exceeding 10 mg Cd kg−1soil a residual fraction appeared, perhaps from precipitation of Cd. Most of the Cd was associated with carbonates; land management and organic matter content had no major effects on the Cd distribution among different soil phases. The extraction protocols were effective for studying the fate of Cd in this calcareous soil as almost all of the Cd added was recovered. However, the introduction of a preliminary step with buffered NH4NO3improved the determination of the most labile pools. Availability of Cd in calcareous soils estimated with reference methods appeared to be very small even when its total concentration far exceeded the current EU limits.
Temperature‐dependent energy budget of an Arctic Cladoceran, Daphnia middendorffiana
Authors: Yurista Peder M.
Published: December 2004

1. Global change models predict the greatest impact in climate to occur in the northern polar region. Change in temperature will alter individual metabolism and has the potential to change community structure to an unknown degree.

2. The temperature‐dependent energy budget of Arctic Daphnia middendorffiana was investigated by measuring respiration rates, ingestion rates and assimilation rates. The scope for growth and reproduction was determined and compared with data from the literature for a clone of Daphnia pulicaria collected in the temperate zone.

3. A difference was observed between the Arctic species and the temperate zone clone in both temperature tolerance, and the energy available for growth and reproduction at various temperatures. A low availability of energy for growth and reproduction indicated that life history patterns as well as physiological mechanisms are important in allowing D. middendorffiana to exist successfully in Arctic environments.

4. The lower available energy for growth compared to Daphnia clones from temperate zones may be detrimental to D. middendorffiana, which might have to compete with species expanding their range under the predicted temperature increase for Arctic regions.
Factors which affect the abundance of an invasive cladoceran, Daphnia lumholtzi, in U.S. reservoirs
Authors: Work Kirsten A. , Gophen Moshe
Published: December 2004

1. Daphnia lumholtzi is a subtropical, Old World species which is rapidly spreading throughout reservoirs in the southern U.S.A. It was first recorded in Lake Texoma (Oklahoma–Texas) in September 1991.

2. Southern U.S. reservoirs typically have strong spatial and temporal gradients in temperature, conductivity, turbidity and in the distribution of organisms. Therefore, the present experiments examined the reproductive and moulting rates, and survival of D. lumholtzi in relation to extremes of food concentration, temperature, conductivity and turbidity.

3. Increases in temperature (range = 15–29 °C) and decreases in turbidity (range = 0.6–470 NTU) increased reproductive and moulting rates, whereas food concentration only affected the rate of reproduction, while conductivity had no effects. Survival was affected only by temperature.

4. Daphnia lumholtzi tolerates high temperatures (27–30 °C) at which other cladocerans in Lake Texoma disappear. Therefore, D. lumholtzi may exploit resources in midsummer, when there are few potential competitors.
Responses of phytoplankton and epilithon during acidification and early recovery of a lake
Authors: Findlay D. L. , Kasian S. E. M. , Turner M. T. , Stainton M. P.
Published: December 2004

1. Lake 302S in the Experimental Lakes Area of Canada was acidified from pH 6.7 (1981) to 5.1 (1986). The pH was further reduced to 4.5 in 1987 and held at that level until 1991. From 1992 to 1995, the pH was allowed to increase to a target value of 5.8.

2. The response of the phytoplankton community to decreasing pH from 6.0 to 5.1 was similar to that observed in another experimentally acidified lake (223) and in other atmospherically acidified lakes. Acidification affected species diversity of both the phytoplankton and epilithon. Phytoplankton diversity was positively correlated with pH. Epilithic algal diversity was more variable and did not correlate with pH.

3. Phytoplankton biomass was enhanced by acidification as the assemblage shifted from a dominance of chrysophytes to large dinoflagellates (Gymnodinium sp. and Peridinium inconspicuum). Epilithon biomass was unaffected, but dominance shifted from filamentous cyanophytes (Lyngbya) to acidophilic diatoms (Tabellaria quadriseptata and Anomoeonis brachysira).

4. The only taxon to be similarly affected in both the phytoplankton and epilithon was the cyanobacteria, being significantly reduced below pH 5.1. During early recovery (pH 5.5–5.8), cyanobacteria increased and species present prior to acidification recolonized both habitats.

5. In the early stages of recovery, planktonic and benthic assemblages remained more similar to acidified than natural assemblages, but more profound change began at pH > 5.5.
The dynamics of egg production, oviposition and resorption in a parasitoid wasp
Authors: RIVERO‐LYNCH A. P. , GODFRAY H. C. J.
Published: December 2004

1. The extent to which parasitoid wasps are limited by their egg supply is very important in understanding their reproductive strategies. Egg reserves are dynamic, with most wasps maturing new eggs throughout their life (synovigeny) and many species resorbing eggs that are not used in oviposition. We investigated the extent to which a parasitoid modulates its egg reserves in the light of its experience in finding hosts.

2. The egg dynamics of the Encyrtid Wasp Leptomastix dactylopii, a solitary parasitoid of mealybugs, were studied in the laboratory. This species is synovigenic and practises egg resorption.

3. We allowed newly emerged wasps to experience one of four environments of increasing value in terms of reproductive opportunities. We proposed that wasps that experienced good quality environments would maintain more mature eggs ready for oviposition. Dissection of wasps subject to different periods of host deprivation after the experimental treatment failed to confirm the hypothesis: egg load was independent of experience.

4. We also proposed that any adjustment of egg supply to make up for eggs oviposited would be effected through a reduction in egg resorption. Instead, we found that the wasp quickly made up for eggs oviposited by increased egg production.
The effects of substrate and vertebral number on locomotion in the garter snake Thamnophis elegans
Authors: KELLEY K. C. , ARNOLD S. J. , GLADSTONE J.
Published: December 2004

1. Locomotor performance of limbless vertebrates depends on the substrate through which individuals move and may result in selection on vertebral number in different habitats. To evaluate the effect of push‐point density on snake locomotion, the density of vegetation and other potential push‐points was quantified at two sites in California (coastal and inland), where conspecific snakes differed greatly in vertebral number (230 and 256 average total vertebrae, respectively; Arnold 1988). The coastal site had significantly higher push‐point densities than the inland site.

2. Five experimental push‐point densities that fell within the natural range of push‐point densities were employed in laboratory trials of juvenile snake locomotion. Density of push‐points significantly affected both crawling speed and head‐to‐tail distance (HTD), an indirect measure of lateral bending. The fastest speed was achieved at an intermediate push‐point density. The shortest HTD occurred when snakes moved through the lowest push‐point density.

3. Sex, total number of vertebrae and total length significantly affected HTD, regardless of push‐point density. Snakes with relatively more vertebrae had a shorter HTD, suggesting they were able to achieve greater lateral bending than snakes with fewer vertebrae. Coastal and inland populations did not differ in HTD during locomotion.

4. Numbers of body and tail vertebrae significantly influenced speed at different push‐point densities. In general, snakes with more body vertebrae were slower than those with fewer, while snakes with more tail vertebrae were faster than those with fewer. Snakes of greater total length were faster at all densities. Coastal snakes crawled faster than inland snakes at all push‐point densities.
Limits to the distribution of the southern African Ice Rat (Otomys sloggetti): thermal physiology or competitive exclusion?
Authors: RICHTER T. A. , WEBB P. I. , SKINNER J. D.
Published: December 2004

1. We test the hypothesis that the thermal physiology of Otomys sloggetti restricts its distribution to altitudes above 2000 m, below which it does not occur.

2. The thermal physiology of O. sloggetti is typical of rodents from warm/hot areas: the thermoneutral zone is relatively broad and lies between 26 and 28 °C; the upper limit of the thermoneutral zone can be extended by 4 °C through the use of hyperthermia; basal metabolic rate concurs with the allometrically predicted value; the lower critical temperature is high; minimal thermal conductance is 21% higher than the allometrically predicted value; and the capacity for noradrenaline‐induced non‐shivering thermogenesis is 19% lower than the allometrically predicted value.

3. Evaporative water loss and water flux rates are high and typical of mesic‐adapted rodents.

4. The absence of O. sloggetti from warmer, lower‐lying habitats cannot be attributed to its thermal physiology. We suggest that non‐physiological factors, such as interspecific competition with Otomys irroratus, are more likely to restrict the distribution of O. sloggetti.
Analysis of pollinator foraging: tests for non‐random behaviour
Authors: JONES K. N.
Published: December 2004

1. A standardized protocol for analysing the behaviour of pollinators foraging on more than one plant type (species or morph) is needed.

2. A protocol is presented in which the first step is to test whether foraging trips are homogeneous in the frequency of visits to each plant type, or whether there are two or more groups of pollinators with different foraging preferences.

3. Tests for foraging preference and constancy in the sequence of plants visited then should be made separately for each homogeneous group.

4. A hypothetical example is given in which ignoring heterogeneity of preference would lead to the acceptance of a false null hypothesis of random behaviour.

5. A real example is given in which heterogeneity of preference was the only non‐random aspect of pollinator behaviour (no significant positive constancy or overall preference), while transfer of powdered dye particles (pollen analogues) was assortative among floral morphs.

6. Heterogeneity of preference is probable, as many factors may cause individual pollinators to forage differently on the same patch of plants, and may be sufficient to produce non‐random pollen transfer among plant morphs.
Conditionally immortalized cell lines with differentiated functions established from temperature‐sensitive T‐antigen transgenic mice
Authors: Obinata Masuo
Published: December 2004

A variety of cell lines with differentiated functions are required to study tissue functions at cellular and molecular levels. Using transgenic mice harbouring ubiquitously expressing the temperature‐sensitive T‐antigen (ts T‐antigen) gene of simian virus 40 (SV40), many cell lines were generated. The properties of these established lines suggested that their growth was dependent on T‐antigen, and that they retained some of the differentiated functions of each particular tissue. A possible use of these cell lines for tissue functions in vitro is discussed.
Autoregulation of Pax6 transcriptional activation by two distinct DNA‐binding subdomains of the paired domain
Authors: Yamaguchi Yuki , Sawada Jun‐ichi , Yamada Masao , Handa Hiroshi , Azuma Noriyuki
Published: December 2004

Background: Pax6 is a transcription factor that plays a central role in eye development. Pax6 contains a DNA‐binding domain called paired domain, which consists of a highly conserved N‐terminal subdomain and a variable C‐terminal subdomain. Recent findings have suggested that both subdomains possess distinct DNA‐binding activities.

Results: To understand the mechanism of DNA‐binding and transcriptional activation by Pax6 via these subdomains, we employed Pax6 paired domain mutants previously isolated from patients with ocular disorders. Analysis of these mutants by gel shift assay revealed that the N‐terminal and C‐terminal subdomains can independently bind to their respective cognate sites, P6CON and 5aCON. Results from a luciferase assay, however, showed that the two functional subdomains negatively regulate their transactivation potentials each other. Wild‐type Pax6 and its hyperactive variants show different patterns of DNA contact.

Conclusion: These results support a new model for the regulation of Pax6 transactivation: When one DNA‐binding subdomain binds to its cognate site, the other subdomain also interacts with the flanking sequences nonspecifically, and this interaction constrains its structure to give a reduced level of transactivation.
North Dakota's Badlands
Authors: BLUEMLE JOHN P.
Published: December 2004

Rugged badlands carved from rocks ranging in age from late Cretaceous through Eocene occur along the Little Missouri River in western North Dakota, USA
Soil carbon inventories and δ13C along a moisture gradient in Botswana
Authors: Bird M. I. , Veenendaal E. M. , Lloyd J. J.
Published: December 2004

We present a study of soil organic carbon (SOC) inventories and δ13C values for 625 soil cores collected from well‐drained, coarse‐textured soils in eight areas along a 1000 km moisture gradient from Southern Botswana, north into southern Zambia. The spatial distribution of trees and grass in the desert, savannah and woodland ecosystems along the transect control large systematic local variations in both SOC inventories and δ13C values. A stratified sampling approach was used to smooth this variability and obtain robust weighted‐mean estimates for both parameters.

Weighted SOC inventories in the 0–5 cm interval of the soils range from 7 mg cm−2 in the driest area (mean annual precipitation, MAP=225 mm) to 41±12 mg cm−2 in the wettest area (MAP=910 mm). For the 0–30 cm interval, the inventories are 37.8 mg cm−2 for the driest region and 157±33 mg cm−2 for the wettest region. SOC inventories at intermediate sites increase as MAP increases to approximately 400–500 mm, but remain approximately constant thereafter. This plateau may be the result of feedbacks between MAP, fuel load and fire frequency.

Weighted δ13C values decrease linearly in both the 0–5 and 0–30 cm depth intervals as MAP increases. A value of –17.5±1.0‰ characterizes the driest areas, while a value of −25±0.7‰ characterizes the wettest area. The decrease in δ13C value with increasing MAP reflects an increasing dominance of C3 vegetation as MAP increases. SOC in the deeper soil (5–30 cm depth) is, on average, 0.4±0.3‰ enriched in 13C relative to SOC in the 0–5 cm interval.
Genetic variation in germination, growth, and survivorship of red maple in response to subambient through elevated atmospheric CO2
Authors: Mohan Jacqueline E. , Clark James S. , Schlesinger William H.
Published: December 2004

Genetic variation in plant response to atmospheric carbon dioxide (CO2) may have influenced paleo‐vegetation dynamics and could determine how future elevated CO2 drives plant evolution and ecosystem productivity. We established how levels of relatedness – the maternal family, population, and provenance – affect variation in the CO2 response of a species. This 2‐year growth chamber experiment focused on the germination, growth, biomass allocation, and survivorship responses of Acer rubrum to four concentrations of CO2: 180, 270, 360, and 600 μL L−1– representing Pleistocene through potential future conditions. We found that all levels of relatedness interacted with CO2 to contribute to variation in response. Germination responses to CO2 varied among families and populations, growth responses depended on families and regions of origin, and survivorship responses to CO2 were particularly affected by regional identities. Differences among geographic regions accounted for 23% of the variation in biomass response to CO2. If seeds produced under subambient CO2 conditions behave similarly, our results suggest that A. rubrum may have experienced strong selection on seedling survivorship at Pleistocene CO2 levels. Further, this species may evolve in response to globally rising CO2 so as to increase productivity above that experimentally observed today. Species responses to future atmospheric CO2 and the accompanying biotic effects on the global carbon cycle will vary among families, populations, and provenances.
Checklists for nursing libraries: checklist 3, current awareness services
Authors:   SOUTH WEST THAMES REGIONAL LIBRARY SERVICE
Published: December 2004

A series of checklists has been prepared by the Nursing Libraries Working Party of the South West Thames Regional Library Service. They are intended to assist librarians and tutors in building up their libraries' stock and services. They list items that are of particular value to nurses, together with addresses and other useful information.
Checklists for nursing libraries: checklist 5, reference works
Authors:   SOUTH WEST THAMES REGIONAL LIBRARY SERVICE
Published: December 2004

A series of checklists has been prepared by the Nursing Libraries Working Party of the South West Thames Regional Library Service. They are intended to assist librarians and tutors in building up their libraries' stock and services. They list items that are of particular value to nurses, together with addresses and other useful information.
Effect of tubule orientation in the cavity wall on the seal of dental filling materials: an in vitro study
Authors: Wu  , De Gee  , Wesselink
Published: December 2004

Dentinal tubules are oriented perpendicularly to the root canal walls but parallel to the lateral walls of class I occlusal preparation. It was hypothesized that the contact surface area of the material may depend on the tubule orientation in the cavity wall to which the material is applied, and that the difference in contact surface may affect the seal provided by the filling material. Standard central lumens, 2.6 mm in diameter and 3 mm high, were machined in human crown or root specimens. After removal of the smear layer with a conditioner, the specimens in each experimental group, consisting of 20 crown and 20 root specimens, were filled with amalgam, Fuji II glass ionomer (with or without varnish), or gutta‐percha with Ketac‐Endo root canal sealer. A modified fluid transport model was used to test the leakage along the fillings. Selected specimens were then split longitudinally and observed in a scanning electron microscope. The micrographs showed that all the test materials were pressed into the dentinal tubules. The contact surface of the material was calculated to be at least 45% larger in root specimens than in crown specimens, depending on the depth of the tubular penetration of the test material. The leakage results showed that all the test materials leaked less in root specimens than in crown specimens (P= 0.0000 for amalgam, P= 0.0374 for Fuji II with varnish, P= 0.0088 for Fuji II without varnish, P= 0.002 for gutta‐percha with sealer). It was concluded that the tubule orientation in the cavity wall may influence the seal provided by certain dental filling materials.
A challenge for community psychiatric nursing: is there a future in primary health care?
Authors: Hannigan Ben
Published: December 2004

The growing debate surrounding the role of the community psychiatric nurse (CPN) in the United Kingdom is reviewed. Issues which have attracted significant interest and which form the focus of this paper are the prioritization of CPN services, CPN attachment to primary health care (PHC), and the effectiveness of clinical interventions. The requirement for CPNs is now to concentrate services on people experiencing severe and enduring mental health problems. Innovative and effective clinical and social interventions for this client group are beginning to disseminate into everyday CPN practice. Problem‐solving family interventions, cognitive therapies and case management are three such examples. The past, present and possible future role for CPNs working in primary health care settings with people experiencing nonpsychotic mental health problems is a particular focus in this paper. Drawing on the relevant literature, central issues addressed are the process and outcome of CPN work with nonpsychotic service users, reasons for the growth of CPN involvement in PHC, and the overall expansion of interest in mental health interventions within the primary health care environment. The literature suggests that this expansion has been strategically unplanned, but that mental health need amongst primary health care service users is significant. The concluding contention of this paper is that a future role for CPNs in primary care does exist.
Nursing students' and faculty's perceptions of the characteristics of ‘best’ and ‘worst’ clinical teachers: a replication study
Authors: Kotzabassaki Stella , Panou Maria , Dimou Fotini , Karabagli Athina , Koutsopoulou Basiliki , Ikonomou Urania
Published: December 2004

This replication study described and compared the characteristics of ‘best’ and ‘worst’ clinical teachers as perceived by 185 Greek students of nursing and 31 clinical teachers. It is a replication of Mogan & Knox's (1987) study, which has also been replicated by Nehring (1990). The Nursing Clinical Teacher Effectiveness Inventory (NCTEI) was used for data collection. This tool is a 48‐item seven‐point‐scale checklist which describes discrete teacher characteristics grouped in five categories or subscales. Subjects were invited to rate their ‘best’ clinical teacher using the NCTEI, and then their ‘worst’ clinical teacher. Faculty's and students' perceptions agreed with most of the highest‐rated characteristics of the ‘best’ clinical teachers. There was less agreement in the lowest‐rated characteristics of the ‘worst’ teachers. There were not significant differences between the rating of students and faculty when categories of characteristics were compared, with the exception of the category ‘interpersonal relationship’ of the ‘worst’ teachers. The most distinguishing characteristics between ‘best’ and ‘worst’ clinical teachers for students and faculty in this study and in both Mogan & Knox's and Nehring's samples, were being a good role model and encouraging a climate of mutual respect.
The effects of an HIV/AIDS educational programme on the anxiety level of nursing students
Authors: All Anita C. , Sullivan Linda
Published: December 2004

Acquired immunodeficiency syndrome (AIDS) is a serious disease that has special concern for the health care provider. AIDS has continued to grow despite control efforts. As the disease infectivity period remains lengthy, and the heterosexual population is affected to a greater degree, the level of anxiety has also risen despite educational endeavours. Many fears and anxieties have been associated with AIDS patients by health care workers. The reduction of stress, perceived risk and discomfort following educational efforts have been supported in past research. Educational programmes will need to be given for current health care workers at all levels as well as nursing students. Future nurses must be prepared to meet this challenge. This study was conducted using a convenience sample of nursing students at a university in western United States. Its purpose was to assess any changes that occurred in state anxiety following an educational presentation. Spielberge's State‐Trait Anxiety Inventory was used as the measurement instrument. Some anxiety levels were significantly reduced.
Teams and seams: skill mix in primary care
Authors: Jenkins‐Clarke Susan , Carr‐Hill Roy , Dixon Paul
Published: December 2004

Teams and seams: skill mix in primary care ¶The study described in this paper is set against a background of rapid changes in primary (community) care delivery in the United Kingdom (UK) and consequently the methodology of the study has been shaped by three broad issues — workforce changes, increase in workload and changing roles and boundaries. Ten ‘ordinary’ general practices (general practitioners (GPs) and the ‘attached’ community nurses) participated in the study and a large amount of data were collected over a 2‐week observation period. Three study objectives are described, relating to workload, delegation and attitudes to delegation. The characteristics of the workload of the three main groups of community nurses (practice nurses, district nurses and health visitors) are described and compared. Thirty‐nine per cent of all the GP consultations (836) had a delegatable element and 17% were deemed to be delegatable in their entirety. General practitioners most frequently referred to delegation to practice nurses in the current team and nurse practitioners in an enhanced team. The study identified the activities most amenable to delegation to these two groups of nurses. Attitudes to delegation were sought through focus group discussions, with reservations being expressed by both doctors and community nurses. This study provides evidence that GPs are prepared to delegate a considerable proportion of their workload; this clearly has implications for the nursing profession.
Critical thinking skills: the role of prior experience
Authors: Bethune Elizabeth , Jackling Noel
Published: December 2004

The critical thinking skills students bring with them on entering university courses will necessarily have a bearing on how they manage their studies and gain new knowledge. This study examined postgraduate nursing students'perceptions of their gains in critical thinking abilities through engagement in off‐campus studies after three semesters of study. Data for the study were collected by survey methodology. Descriptive statistics were derived and correlation analyses performed using SPSSx. This study indicates that for most skills, the differences between those students with prior university experience and those without it in perceptions of change in skill ability were not marked. For most critical thinking skills, about one half or a little more of the students perceived an overall positive shift in their abilities. For some skills, however, there were marked differences in the proportion of students perceiving a shift in skill ability, and possible explanations are offered. The results also indicate that a considerable proportion of the students surveyed perceived a lack of critical thinking skill development. As a result questions can be raised about how off‐campus students without prior university experience engage with tertiary studies. The implications of these findings in terms of the development of off‐campus nursing course materials and student learning are discussed.
Cancer and beyond: the question of survivorship
Authors: Breaden Katrina
Published: December 2004

Today, more people are surviving cancer as a result of improved treatment and early diagnosis. In Australia, the 5‐year survival rate for persons diagnosed with cancer is now approaching 50%. Although there is a growing population of cancer survivors, little is known about what surviving entails. Traditionally, a survivor has been defined as one who has been disease‐free for more than 5 years. However, this definition does not take into account the experience nor the process of survival and the aim of this article is to document the process of surviving cancer as reflected in the experiences of cancer survivors. Using a method of hermeneutic phenomenology (as described by van Manen), the study draws on the stories of six women, who by their definition, are surviving cancer. A discussion of themes has been structured according to the everyday experiences of living in a body and living in time. The women describe a survival process that includes: ‘feeling whole again’; ‘the body as the house of suspicion’; ‘the future in question’; ‘changes in time’; ‘lucky to be alive’; and ‘sharing the journey’.
Stigma
Authors: Brunton Keith
Published: December 2004

This study started as a literature review on stigma as part of a Professional Studies II Resettlement Course. While conducting the study the author was able to follow‐up previous research which looked at contact with the mentally ill and stigma. The authors Trust opened a new community mental health base and the study looked at local residents'attitudes towards the mentally ill both 6 months prior to the opening and again 6 months after. A control area 5 miles from the base was also surveyed on both occasions. The study found that the opening of the base had little or no effect on the attitudes of local residents. However, there was evidence that attitudes towards the mentally ill had hardened both locally and within the control area.