bluuebunny/crossref_metadata_2025 huggingface dataset:
Scientific Representation, Interpretation, and Surrogative Reasoning
Authors: Contessa Gabriele
Published: September 2007

In this paper, I develop Mauricio Suárez's distinction between denotation, epistemic representation, and faithful epistemic representation. I then outline an interpretational account of epistemic representation, according to which a vehicle represents a target for a certain user if and only if the user adopts an interpretation of the vehicle in terms of the target, which would allow them to perform valid (but not necessarily sound) surrogative inferences from the model to the system. The main difference between the interpretational conception I defend here and Suárez's inferential conception is that the interpretational account is a substantial account—interpretation is not just a “symptom” of representation; it is what makes something an epistemic representation of a something else.
Distinct Sequence Elements of Cyclin B1 Promote Localization to Chromatin, Centrosomes, and Kinetochores during Mitosis
Authors: Bentley Anna M. , Normand Guillaume , Hoyt Jonathan , King Randall W.
Published: September 2007

The mitotic cyclins promote cell division by binding and activating cyclin-dependent kinases (CDKs). Each cyclin has a unique pattern of subcellular localization that plays a vital role in regulating cell division. During mitosis, cyclin B1 is known to localize to centrosomes, microtubules, and chromatin. To determine the mechanisms of cyclin B1 localization in M phase, we imaged full-length and mutant versions of human cyclin B1-enhanced green fluorescent protein in live cells by using spinning disk confocal microscopy. In addition to centrosome, microtubule, and chromatin localization, we found that cyclin B1 also localizes to unattached kinetochores after nuclear envelope breakdown. Kinetochore recruitment of cyclin B1 required the kinetochore proteins Hec1 and Mad2, and it was stimulated by microtubule destabilization. Mutagenesis studies revealed that cyclin B1 is recruited to kinetochores through both CDK1-dependent and -independent mechanisms. In contrast, localization of cyclin B1 to chromatin and centrosomes is independent of CDK1 binding. The N-terminal domain of cyclin B1 is necessary and sufficient for chromatin association, whereas centrosome recruitment relies on sequences within the cyclin box. Our data support a role for cyclin B1 function at unattached kinetochores, and they demonstrate that separable and distinct sequence elements target cyclin B1 to kinetochores, chromatin, and centrosomes during mitosis.
p21waf1/cip1/sdi1as a Central Regulator of Inducible Smooth Muscle Actin Expression and Differentiation of Cardiac Fibroblasts to Myofibroblasts
Authors: Roy Sashwati , Khanna Savita , Rink Trenton , Radtke Jared , Williams W. Taylor , Biswas Sabyasachi , Schnitt Rebecca , Strauch Arthur R. , Sen Chandan K.
Published: September 2007

The phenotypic switch of cardiac fibroblasts (CFs) to myofibroblasts is essential for normal and pathological wound healing. Relative hyperoxic challenge during reoxygenation causes myocardial remodeling. Here, we sought to characterize the novel O2-sensitive molecular mechanisms responsible for triggering the differentiation of CFs to myofibroblasts. Exposure of CFs to hyperoxic challenge–induced transcription of smooth muscle actin (SMA) and enhanced the stability of both Acta2 transcript as well as of SMA protein. Both p21 deficiency as well as knockdown blunted hyperoxia-induced Acta2 and SMA response. Strikingly, overexpression of p21 alone markedly induced differentiation of CFs under normoxia. Overexpression of p21 alone induced SMA transcription by down-regulating YB1 and independent of TGFβ1. In vivo, hyperoxic challenge induced p21-dependent differentiation of CFs to myofibroblasts in the infarct boundary region of ischemia-reperfused heart. Tissue elements were laser-captured from infarct boundary and from a noninfarct region 0.5 mm away. Reperfusion caused marked p21 induction in the infarct region. Acta2 as well as SMA expression were markedly up-regulated in CF-rich infarct boundary region. Of note, ischemia-reperfusion–induced up-regulation of Acta2 in the infarct region was completely abrogated in p21-deficient mice. This observation establishes p21 as a central regulator of reperfusion-induced phenotypic switch of CFs to myofibroblasts.
Antibody to AP1B Adaptor Blocks Biosynthetic and Recycling Routes of Basolateral Proteins at Recycling Endosomes
Authors: Cancino Jorge , Torrealba Carolina , Soza Andrea , Yuseff María Isabel , Gravotta Diego , Henklein Peter , Rodriguez-Boulan Enrique , González Alfonso
Published: September 2007

The epithelial-specific adaptor AP1B sorts basolateral plasma membrane (PM) proteins in both biosynthetic and recycling routes, but the site where it carries out this function remains incompletely defined. Here, we have investigated this topic in Fischer rat thyroid (FRT) epithelial cells using an antibody against the medium subunit μ1B. This antibody was suitable for immunofluorescence and blocked the function of AP1B in these cells. The antibody blocked the basolateral recycling of two basolateral PM markers, Transferrin receptor (TfR) and LDL receptor (LDLR), in a perinuclear compartment with marker and functional characteristics of recycling endosomes (RE). Live imaging experiments demonstrated that in the presence of the antibody two newly synthesized GFP-tagged basolateral proteins (vesicular stomatitis virus G [VSVG] protein and TfR) exited the trans-Golgi network (TGN) normally but became blocked at the RE within 3–5 min. By contrast, the antibody did not block trafficking of green fluorescent protein (GFP)-LDLR from the TGN to the PM but stopped its recycling after internalization into RE in ∼45 min. Our experiments conclusively demonstrate that 1) AP1B functions exclusively at RE; 2) TGN-to-RE transport is very fast and selective and is mediated by adaptors different from AP1B; and 3) the TGN and AP1B-containing RE cooperate in biosynthetic basolateral sorting.
Role of Hsp104 in the Propagation and Inheritance of the [Het-s] Prion
Authors: Malato Laurent , Dos Reis Suzana , Benkemoun Laura , Sabaté Raimon , Saupe Sven J.
Published: September 2007

The chaperones of the ClpB/HSP100 family play a central role in thermotolerance in bacteria, plants, and fungi by ensuring solubilization of heat-induced protein aggregates. In addition in yeast, Hsp104 was found to be required for prion propagation. Herein, we analyze the role of Podospora anserina Hsp104 (PaHsp104) in the formation and propagation of the [Het-s] prion. We show that ΔPaHsp104 strains propagate [Het-s], making [Het-s] the first native fungal prion to be propagated in the absence of Hsp104. Nevertheless, we found that [Het-s]-propagon numbers, propagation rate, and spontaneous emergence are reduced in a ΔPaHsp104 background. In addition, inactivation of PaHsp104 leads to severe meiotic instability of [Het-s] and abolishes its meiotic drive activity. Finally, we show that ΔPaHSP104 strains are less susceptible than wild type to infection by exogenous recombinant HET-s(218–289) prion amyloids. Like [URE3] and [PIN+] in yeast but unlike [PSI+], [Het-s] is not cured by constitutive PaHsp104 overexpression. The observed effects of PaHsp104 inactivation are consistent with the described role of Hsp104 in prion aggregate shearing in yeast. However, Hsp104-dependency appears less stringent in P. anserina than in yeast; presumably because in Podospora prion propagation occurs in a syncitium.
Effect of the mutation rate and background size on the quality of pathogen identification
Authors: Reed Chris , Fofanov Viacheslav , Putonti Catherine , Chumakov Sergei , Slezak Tom , Fofanov Yuriy
Published: September 2007

Motivation: Genomic-based methods have significant potential for fast and accurate identification of organisms or even genes of interest in complex environmental samples (air, water, soil, food, etc.), especially when isolation of the target organism cannot be performed by a variety of reasons. Despite this potential, the presence of the unknown, variable and usually large quantities of background DNA can cause interference resulting in false positive outcomes.

Results: In order to estimate how the genomic diversity of the background (total length of all of the different genomes present in the background), target length and target mutation rate affect the probability of misidentifications, we introduce a mathematical definition for the quality of an individual signature in the presence of a background based on its length and number of mismatches needed to transform the signature into the closest subsequence present in the background. This definition, in conjunction with a probabilistic framework, allows one to predict the minimal signature length required to identify the target in the presence of different sizes of backgrounds and the effect of the target's mutation rate on the quality of its identification. The model assumptions and predictions were validated using both Monte Carlo simulations and real genomic data examples. The proposed model can be used to determine appropriate signature lengths for various combinations of target and background genome sizes. It also predicted that any genomic signatures will be unable to identify target if its mutation rate is >5%.

Contact:  yfofanov@bioinfo.uh.edu

Supplementary information: Supplementary data are available at Bioinformatics online.
Characterization of AtALMT1 Expression in Aluminum-Inducible Malate Release and Its Role for Rhizotoxic Stress Tolerance in Arabidopsis
Authors: Kobayashi Yuriko , Hoekenga Owen A. , Itoh Hirotaka , Nakashima Midori , Saito Shoichiro , Shaff Jon E. , Maron Lyza G. , Piñeros Miguel A. , Kochian Leon V. , Koyama Hiroyuki
Published: September 2007

Malate transporters play a critical role in aluminum (Al) tolerance responses for some plant species, such as Arabidopsis (Arabidopsis thaliana). Here, we further characterize AtALMT1, an Arabidopsis aluminum-activated malate transporter, to clarify its specific role in malate release and Al stress responses. Malate excretion from the roots of accession Columbia was sharply induced by Al, which is concomitant with the induction of AtALMT1 gene expression. The malate release was specific for Al among rhizotoxic stressors, namely cadmium, copper, erbium, lanthanum, sodium, and low pH, which accounts for the specific sensitivity of a null mutant to Al stress. Al-specific malate excretion can be explained by a combined regulation of AtALMT1 expression and activation of AtALMT1 protein, which is specific for Al. Although low pH treatment slightly induced gene expression, other treatments did not. In addition, malate excretion in Al-activated seedlings was rapidly stopped by removing Al from the solution. Other rhizotoxic stressors were not effective in maintaining malate release. Protein kinase and phosphatase inhibitor studies indicated that reversible phosphorylation was important for the transcriptional and posttranslational regulation of AtALMT1. AtALMT1 promoter-β-glucuronidase fusion lines revealed that AtALMT1 has restricted expression within the root, such that unnecessary carbon loss is likely minimized. Lastly, a natural nonsense mutation allele of AtALMT1 was identified from the Al-hypersensitive natural accession Warschau-1.
Early Steps in Proanthocyanidin Biosynthesis in the Model Legume Medicago truncatula
Authors: Pang Yongzhen , Peel Gregory J. , Wright Elane , Wang Zengyu , Dixon Richard A.
Published: September 2007

Oligomeric proanthocyanidins (PAs) composed primarily of epicatechin units accumulate in the seed coats of the model legume Medicago truncatula, reaching maximal levels at around 20 d after pollination. Genes encoding the single Medicago anthocyanidin synthase (ANS; EC 1.14.11.19) and leucoanthocyanidin reductase (LAR; EC 1.17.1.3) were cloned and the corresponding enzymes functionally identified. Recombinant MtANS converted leucocyanidin to cyanidin, and, more efficiently, dihydroquercetin to the flavonol quercetin. Levels of transcripts encoding dihydroflavonol reductase, ANS, and anthocyanidin reductase (ANR), the enzyme responsible for conversion of anthocyanidin to (−)-epicatechin, paralleled the accumulation of PAs in developing seeds, whereas LAR transcripts appeared to be more transiently expressed. LAR, ANS, and ANR proteins were localized to the cytosol in transfected tobacco (Nicotiana tabacum) leaves. Antisense down-regulation of ANS in M. truncatula resulted in reduced anthocyanin and PA levels, but had no impact on flavonol levels. Transgenic tobacco plants constitutively overexpressing MtLAR showed reduced anthocyanin content, but no catechin or increased levels of PAs were detected either in leaves or in flowers. Our results confirm previously ascribed in vivo functions for ANS and ANR. However, the apparent lack of catechin in M. truncatula PAs, the poor correlation between LAR expression and PA accumulation, and the lack of production of catechin monomers or oligomers in transgenic plants overexpressing MtLAR question the role of MtLAR in PA biosynthesis in Medicago.
FURTHER EVIDENCE ON MEAN REVERSION IN THE AUSTRALIAN EXCHANGE RATE
Authors: Darné Olivier , Hoarau Jean‐François
Published: September 2007

In this paper we re‐examine the purchasing power parity (PPP) in Australia for the period February 1970 to April 2005 using an alternative method relative to the previous studies. We underlined large shocks due to depreciations that affected the Australian exchange rate, using outlier methodology. Once we adjusted the data of these outliers that had large, but either temporary or permanent effects on the series, our results show that there is no tendency for PPP in Australia to hold in the long run during this period.
PREMATURE MORTALITY AND POVERTY MEASUREMENT
Authors: Kanbur Ravi , Mukherjee Diganta
Published: September 2007

There is a glaring paradox in all commonly used measures of poverty. The death of a poor person, because of poverty, reduces poverty according to these measures. This surely violates our basic intuitions of how poverty measures should behave. It cannot be right in concept that differentially higher mortality among the poor serves to reduce poverty. This article begins the task of developing poverty measures that are not perversely mortality sensitive. A family of measures is proposed that is an intuitive modification of standard poverty measures to take into account the fact that the rich live longer than the poor.
Land cover change 2002–2005 in Borneo and the role of fire derived from MODIS imagery
Authors: LANGNER ANDREAS , MIETTINEN JUKKA , SIEGERT FLORIAN
Published: September 2007

Borneo has experienced heavy deforestation and forest degradation during the past two decades. In this study the Moderate Resolution Imaging Spectroradiometer was used to monitor land cover change in Borneo between 2002 and 2005 in order to assess the current extent of the forest cover, the deforestation rate and the role of fire. Using Landsat and ground observation for validation it was possible to discriminate 11 land cover classes. In 2002 57% of the land surface of Borneo was covered with forest of which 74% was dipterocarp and more than 23% peat swamp forest. The average deforestation rate between 2002 and 2005 was 1.7% yr− 1. The carbon‐rich ecosystem of peat swamp forests showed a deforestation rate of 2.2%. Almost 98% of all deforestation occurred within a range of 5 km to the forest edge. Fire is highly correlated with land cover changes. Most fires were detected in degraded forests. Ninety‐eight per cent of all forest fires were detected in the 5 km buffer zone, underlining that fire is the major driver for forest degradation and deforestation.
Microsatellite abnormalities and somatic down‐regulation of mismatch repair characterize nodular‐trabecular muscle‐invasive urothelial carcinoma of the bladder
Authors: Rubio J , Blanes A , Sanchez‐Carrillo J J , Diaz‐Cano S J
Published: September 2007

Aims:  To correlate histological infiltration patterns with genetic and mismatch repair (MMR) profiles in muscle‐invasive bladder urothelial carcinomas (UroC).

Methods and results:  Infiltration patterns were assessed in the deep compartment of muscle‐invasive UroC (nodular‐trabecular, 45 cases; infiltrative, 27 cases). Tumour compartment (superficial and deep to muscularis mucosa) analysis included: microsatellite pattern of TP53, RB1, WT1 and NF1 by polymerase chain reaction/denaturing gradient gel electrophoresis; mitotic, Ki67, in situ end labelling (ISEL) indices and DNA ploidy. MMR was assessed by MLH1 and MSH2 sequencing and immunohistochemistry in UroC with two or more abnormal microsatellite loci. Statistical differences were tested using anova and Fisher's exact tests. Infiltrative UroC showed lower Ki67 index 14.94 ± 4.28, ISEL index 14.1 ± 10.0 and shorter median survival (20 months) than nodular‐trabecular UroC (Ki67 index 20.65 ± 4.94, ISEL 20.2 ± 22.7, 37‐month survival, respectively). The genetic profile was significantly different for RB1 (P = 0.0003) and NF1 (P = 0.0023) only, being more frequently abnormal in nodular‐trabecular UroC. A significant decrease in MLH1 or MSH2 protein expression with no gene mutations was identified in UroC with microsatellite abnormalities and a nodular‐trabecular growth pattern.

Conclusions:  Somatic down‐regulation of MMR proteins in nodular‐trabecular muscle‐invasive UroC results in RB1/NF1 microsatellite abnormalities, correlating with higher cellular turnover and longer survival.
Intentional replantation for the management of maxillary sinusitis
Authors: Peñarrocha M. , García B. , Martí E. , Palop M. , Von Arx T.
Published: September 2007

Aim  To present a case that emphasizes the importance of the use of intentional replantation as a technique to successfully treat a periapical lesion and an odontogenic maxillary sinusitis through the alveolus at the same time.

Summary  This case report presents a patient with odontogenic maxillary sinusitis secondary to periapical disease of a maxillary molar that had previously received root canal treatment. The molar was extracted, with drainage and rinsing of the maxillary sinus. The apices were resected extra‐orally, the retrograde cavities prepared with ultrasound and retrograde fillings of silver amalgam placed. The tooth was then replanted. After 2 years, the patient was asymptomatic, periapical radiography showed no evidence of root resorption and computed tomography scanning demonstrated the resolution of maxillary sinusitis.

Key learning points 

When root canal treatment or periapical surgery cannot be undertaken or has failed, intentional replantation may be considered.

This alternative treatment may be predictable in certain cases.
Type 2 diabetes‐associated androgen alteration in patients with erectile dysfunction
Authors: El‐Sakka A. I. , Sayed H. M. , Tayeb K. A.
Published: September 2007

Our objective was to assess the pattern of type‐2 diabetes‐associated androgen alteration in patients with erectile dysfunction (ED). A total of 127 diabetic male patients with ED were enrolled in this study. Erectile function was assessed using the International Index of Erectile Function (IIEF). At the time of assessment, patients were also interviewed and assessed for socio‐demographic and medical history that includes duration and severity of diabetes mellitus (DM). Patients underwent routine laboratory investigations, in addition to total testosterone (T), dehydroepiandrosterone sulphate (DHEA‐S) and insulin assessment. The mean age ± SD was 53.8 ± 9.3 years. Of patients 25.2% (n = 32/127), 6.3% (n = 8/127) and 31.5% (n = 40/127) had low total T, low DHEA‐S and hyperinsulinaemia respectively. There were significant association between the increase in age and body mass index and the presence of low T level. Of the patients 37.5% (n = 12/32) with low T level had glycosylated haemoglobin (HbA1c) >7% while, 22.1% (n = 21/95) of the patients with normal T level had HbA1c >7% (p < 0.05). There were significant associations between the number of patients with low level of total T or DHEA‐S and poor control of DM. Patients with low T level were two times more likely (56.3%, n = 18/32) to have severe ED than patients with normal T level (27.4%, n = 26/95) (p < 0.01). There were significant differences between the mean levels of total T or DHEA‐S and poor control of DM. No significant associations were detected between hyperinsulinaemia and the level of fasting blood sugar, duration of DM, metabolic control of DM or ED severity. Patients with low T level were three times as likely to have hyperinsulinaemia as those patients with normal T level (p < 0.05). The current study clearly demonstrated that there were significant associations between low level of total T or DHEA‐S and poor control of DM.
Demographic variation and population viability in a threatened Himalayan medicinal and aromatic herb Nardostachys grandiflora: matrix modelling of harvesting effects in two contrasting habitats
Authors: Ghimire Suresh Kumar , Gimenez Olivier , Pradel Roger , McKey Doyle , Aumeeruddy‐Thomas Yildiz
Published: September 2007

Despite significant interest in the sustainable use of medicinal plants, the population ecology of many medicinal plant species remains unstudied. Also, few demographic studies have compared effects of harvesting across habitats. We studied the demography of a highly threatened perennial Himalayan medicinal herb, Nardostachys grandiflora, in two habitats and examined effects of indigenous harvesting regimes on its population dynamics.

In a rocky‐outcrop population in 1998, different levels of rhizome harvesting were applied directly by the local users. In meadows, we sampled an unharvested population and another population that was commercially harvested. Data on recruitment, growth and survival of individuals classified by size were gathered over 4 years.

Population growth rate (λ) was significantly higher in the unharvested meadow population than in control subplots of the outcrop population. Harvesting significantly reduced λ. Matrix model projections revealed that the size of outcrop populations would return to initial values within ≈5 years, only after 10% rhizome harvesting. In other treatments, recovery time varied from 17 (25% harvesting) to 33 (75%) years. In contrast, in the commercially harvested meadow population (with harvesting levels >25%), projected recovery time was 6 years.

Higher growth rates and faster recovery in meadow populations appear to be due to higher recruitment and faster vegetative growth. In outcrops, slow growth and low fecundity slow down recovery after harvesting.

Synthesis and application. Nardostachys grandiflora is extremely sensitive to harvesting of rhizomes, but this sensitivity is higher in outcrop than in meadow habitats. Given the constraints on its population growth and its high sensitivity to harvesting, N. grandiflora should be strictly managed, with low harvest rates (<10% in outcrop and <25% in meadow) and fairly long rotations (at least 5 years) between successive harvests. This work shows the importance of considering demographic variation across habitats when formulating specific management plans for threatened medicinal plants. It also demonstrates the importance of integrating local harvesting practices in ecological research for informing management. A large proportion of high‐altitude perennial medicinal plants may be expected to be similarly sensitive to exploitation, requiring careful management to achieve sustainable harvesting.
A systematic review and meta‐synthesis: evaluating the effectiveness of nurse, midwife/allied health professional consultants
Authors: Humphreys Ann , Johnson Sarah , Richardson Janet , Stenhouse Elizabeth , Watkins Mary
Published: September 2007

Aim.  This paper presents the findings of a systematic review and meta‐synthesis, which was undertaken to identify and assess studies that evaluated the nurse/midwife/allied health professional consultant role.

Background.  As part of the modernization agenda in the National Health Service the United Kingdom government proposed ‘Consultant’ posts for nurses/midwives and allied health professionals as an opportunity for experienced practitioners to extend their roles. Four key functions were identified as being significant to this role development: expert practice, leadership, education and research. Explicit within the proposal was a requirement of these new roles to be evaluated.

Method.  Inclusion criteria focussed on studies where an aspect of the role had been evaluated or where the consultant carried out the research. A total of 1931 citations was filtered to reveal 107 studies that possibly met the inclusion criteria. Of these 107, 14 studies were critically appraised and subjected to thematic analysis. Study methodology varied but of the 14 studies, 10 involved some form of measurement. The others adopted a literature review or descriptive approach.

Conclusions.  The extent to which consultants were involved in all aspects of the ‘four pillars’ was assessed in only a small number of studies. However, a number of studies implicitly implied active engagement in expert practice and leadership by focussing on specific service developments.

Relevance to clinical practice.  To date, a number of studies evaluating service developments, education, expert practice and leadership have been carried out. However although a number of studies have assessed perceived impact of the consultant role, no measure of actual benefit has been published to date. Studies that evaluate the cost benefit/outcomes of these roles in relation to both activity and quality of service are required.
Plugging a hole and lightening the burden: a process evaluation of a practice education team
Authors: Mallik Maggie , Hunt Jane A
Published: September 2007

Aim.  To investigate the perceptions of clinical and senior managers about the role of practice educators (PEs) employed in one acute hospital in the UK.

Background.  Producing nurses who are fit for practice, purpose and academic award is a key issue for nurse education partnership providers in the UK. Various new models for practice learning support structures and new roles within health care institutions have been established. To sustain funding and policy support for these models, there is a need for evaluation research.

Design.  A process evaluation methodology was employed to determine the current value of a practice education team and to provide information to guide future direction.

Methods.  Data were collected through semi‐structured telephone interviews using a previously designed schedule. All senior nurse managers (n = 5) and a purposive sample of Clinical Managers (n = 13) who had personal experience of and perceptions about the role of PEs provided the data. Interview notes were transcribed, coded and a thematic framework devised to present the results.

Results.  A number of key themes emerged including: qualities needed for being a successful practice educator; visibility and presence of PEs; providing a link with the university; ‘plugging a hole’ in supporting learning needs; providing relief to practitioners in dealing with ‘the burden of students;’ alleviating the ‘plight of students;’ and effects on student attrition.

Conclusions.  Findings provided evidence for the continued funding of the practice educator role with improvements to be made in dealing with stakeholder expectations and outcomes.

Relevance to clinical practice.  In the UK, there still remain concerns about the fitness for practice of newly Registered Nurses, prompting a recent national consultation by the professional regulating body. Despite fiscal pressures, recommendations for further strengthening of all systems that will support the quality of practice learning may continue to sustain practice learning support roles.
Preliminary study to investigate the normal range of Ankle Brachial Pressure Index in young adults
Authors: Male Stuart , Coull Alison , Murphy‐Black Tricia
Published: September 2007

Aim.  The aim of this study was to find the normal range of Ankle Brachial Pressure Index (ABPI) for healthy adults in the 20–40‐year age group. The hypothesis was: there is no difference between the accepted normal value of ABPI (1·00) and the observed value of ABPI in healthy adults in the 20–40‐year age group.

Background.  Doppler ultrasound and ABPI calculations are used in the assessment of lower limb vascularity. Ankle Brachial Pressure Index is used as an indicator for the choice of nursing options for the treatment of chronic leg ulcers. Little research has been done to establish what the normal range of ABPI is in young healthy adults. This information has practical significance to the treatment of young adults who are prone to present with leg ulcers such as i.v. drug users.

Method.  An observational survey was conducted with 24 healthy adults in the 20–40‐year age range (who did not have a history of i.v. drug use).

Results.  The study found that the ABPI ranged from 1·05 to 1·25 (mean = 1·14; SD 0·06). In addition, the study also found that there was a negative correlation between ABPI and observed brachial systolic pressure.

Conclusion.  A ‘normal’ ABPI should not be considered a fixed figure (1·00) and that ABPI may be dependant on an individual's blood pressure and possibly other factors.

Relevance to clinical practice.  Ankle Brachial Pressure Index is a routine procedure undertaken when assessing the vascular supply to the lower legs. The results summarized in this paper will be useful to clinicians attempting to interpret ABPI results in young people.
Absorbent products for incontinence: ‘treatment effects’ and impact on quality of life
Authors: Getliffe Kathryn , Fader Mandy , Cottenden Alan , Jamieson Katharine , Green Nicholas
Published: September 2007

Abstract  Aim.  This study aimed to determine how the use and characteristics of absorbent products for incontinence impact on women's quality of life, and to examine the concept of ‘treatment effects’ in the context of pad use.

Method.  Key pad performance characteristics were identified from the literature and focus group work. Semi‐structured interviews with 99 women with light incontinence were used to investigate the impact of pad use on women's quality of life, including both positive and negative ‘treatment effects’, and to rank pad characteristics by their importance.

Results.  Achieving effective and discrete containment of urine was the dominant factor impacting on women's lives. Sub‐themes embraced physical effects, psychological impact and social functioning. The five pad characteristics ranked most important for day time use were: ‘to hold urine, to contain smell, to stay in place, discreteness, and comfort when wet. For night use discreteness was replaced by to keep skin dry’. High levels of reported anxiety were associated with perceived risk of poor pad performance, lack of discreteness and need for complex regimes for pad management.

Conclusion.  Insufficient attention has been paid to the balance between the beneficial and negative treatment effects of absorbent pads to date. Existing continence‐related quality of life measures are not designed for conditions where change in symptoms is not an outcome measure. The study findings provide the basis for developing a more sensitive, patient‐oriented, quality of life measure for pad‐users which can aid product selection, new product development and inform future evaluative comparisons between products/products and treatments.

Relevance to clinical practice.  This paper illustrates the complex influence on quality of life caused by using absorbent pads to contain incontinence. It raises awareness of the importance of careful selection of the most appropriate pad for each individual to minimize unfavourable side effects, and the need for a new quality of life measure designed for pad‐users.
Consultant nurse–consultant physician: a new partnership for patient‐centred care?
Authors: Graham Iain W
Published: September 2007

Aims and objectives.  The aim was to describe the process of role transition by an individual who has assumed the position of a consultant nurse in cardiovascular health care. The objective was to explain the ‘gestalt’ of being a consultant nurse and how the ‘gestalt’ has evolved.

Background.  The development of the consultant nurse role is new, research has described the value and potential contribution of the role. The literature suggests that the role still requires further evaluation and description to be understood better.

Design.  A free‐association narrative interview method was chosen as the research design.

Method.  An in depth interview, tape‐recorded and analysed along with field note analysis was the method for eliciting the narrative.

Results.  The analysis of the narrative reveals an emerging ‘gestalt’ for being a consultant nurse. Various concepts and phenomena attributable to the role are identified from the experience described. The gestalt explains the journey of the individual through an ‘apprenticeship’ to role attainment, whereby a new sense of professional self or ‘Me’ is realized.

Conclusion.  The significance of the paper lies in the analysis of the narrative and the insights it gives to help other aspirant consultant nurses. It is through the understanding of these insights that individuals could plan their own learning and development to be achieved in the role of consultant nurse.

Relevance to clinical practice.  To be effective and provide effective patient care, one can argue that appropriate learning needs to take place. Those that have been appointed to the role have battled to find achievement and acceptance. These battles may be made easier to win if the role is better understood and appropriate preparation provided. Only then will the real potential of the role be realized in improved patient care outcomes.
The core role of the nurse practitioner: practice, professionalism and clinical leadership
Authors: Carryer Jenny , Gardner Glenn , Dunn Sandra , Gardner Anne
Published: September 2007

Abstract Aim. To draw on empirical evidence to illustrate the core role of nurse practitioners in Australia and New Zealand.

Background. Enacted legislation provides for mutual recognition of qualifications, including nursing, between New Zealand and Australia. As the nurse practitioner role is relatively new in both countries, there is no consistency in role expectation and hence mutual recognition has not yet been applied to nurse practitioners. A study jointly commissioned by both countries’ Regulatory Boards developed information on the core role of the nurse practitioner, to develop shared competency and educational standards. Reporting on this study's process and outcomes provides insights that are relevant both locally and internationally.

Method. This interpretive study used multiple data sources, including published and grey literature, policy documents, nurse practitioner program curricula and interviews with 15 nurse practitioners from the two countries. Data were analysed according to the appropriate standard for each data type and included both deductive and inductive methods. The data were aggregated thematically according to patterns within and across the interview and material data.

Findings. The core role of the nurse practitioner was identified as having three components:dynamic practice, professional efficacy and clinical leadership. Nurse practitioner practice is dynamic and involves the application of high level clinical knowledge and skills in a wide range of contexts. The nurse practitioner demonstrates professional efficacy, enhanced by an extended range of autonomy that includes legislated privileges. The nurse practitioner is a clinical leader with a readiness and an obligation to advocate for their client base and their profession at the systems level of health care.

Conclusion. A clearly articulated and research informed description of the core role of the nurse practitioner provides the basis for development of educational and practice competency standards. These research findings provide new perspectives to inform the international debate about this extended level of nursing practice.

Relevance to clinical practice. The findings from this research have the potential to achieve a standardised approach and internationally consistent nomenclature for the nurse practitioner role.
The cell cycle of Sulfolobus
Authors: Bernander Rolf
Published: September 2007

Much of the current information about the archaeal cell cycle has been generated through studies of the genus Sulfolobus. The overall organization of the cell cycle in these species is well understood, and information about the regulatory principles that govern cell cycle progression is rapidly accumulating. Exciting progress regarding the control and molecular details of the chromosome replication process is evident, and the first insights into the elusive crenarchaeal mitosis and cytokinesis machineries are within reach.
Connecting primary and secondary metabolism: AreB, an IclR‐like protein, binds the AREccaR sequence of S. clavuligerus and modulates leucine biosynthesis and cephamycin C and clavulanic acid production
Authors: Santamarta Irene , López‐García M. Teresa , Pérez‐Redondo Rosario , Koekman Bert , Martín Juan F. , Liras Paloma
Published: September 2007

A protein binding to the autoregulatory element (ARE) upstream of the regulatory ccaR gene of Streptomyces clavuligerus was isolated previously by DNA affinity binding. The areB gene, encoding this protein, is located upstream and in opposite orientation to the leuCD operon of S. clavuligerus; it encodes a 239‐amino‐acid protein of the IclR family with a helix–turn–helix motif at the N‐terminal region. An areB‐deleted mutant, S. clavuligerusΔareB, has been constructed by gene replacement. This strain requires leucine for optimal growth in defined media. Expression of the leuCD operon is retarded in S. clavuligerusΔareB, because AreB binds the areB‐leuCD intergenic region acting as a positive modulator. Clavulanic acid and cephamycin C production are improved in the ΔareB mutant although no drastic difference in ccaR expression was observed. Pure recombinant AreB protein does not bind the AREccaR sequence (as shown by EMSA) unless filtered extracts from S. clavuligerus ATCC 27064‐containing molecules of Mr lower than 10 kDa are added to the binding reaction. Restoration of binding to the AREccaR sequence is not observed when filtered extracts are obtained from the ΔareB mutant, suggesting that biosynthesis of the small‐molecular‐weight effector is also controlled by AreB.
Sea‐level related resedimentation processes on the northern slope of Little Bahama Bank (Middle Pleistocene to Holocene)
Authors: LANTZSCH HENDRIK , ROTH SVEN , REIJMER JOHN J. G. , KINKEL HANNO
Published: September 2007

Middle Pleistocene to Holocene sediment variations observed in a 26 metre long core taken during a cruise of the RV Marion Dufresne are presented. Core MD992202 was retrieved from the northern slope of Little Bahama Bank and provides an excellent example for sedimentation processes in a mid‐slope depositional environment. The sediment composition indicates sea‐level related deposition processes for the past 375 000 years (marine isotope stages 1 to 11). The sediments consist of: (i) periplatform ooze (fine‐grained particles of shallow‐water and pelagic origin) with moderate variations in carbonate content, carbonate mineralogy and grain‐size; and (ii) coarser intervals with cemented debris consisting of massive, poorly sorted, mud‐supported or clast‐supported deposits with an increased high‐magnesium calcite content. During interglacial stages (marine isotope stages 1, 5, 7, 9 and 11) periplatform oozes (i) are characterized by higher aragonite contents, finer grain‐size and higher organic contents, whereas during glacial stages (marine isotope stages 2 to 4, 6, 8 and 10), increased low‐magnesium and high‐magnesium calcite values, coarser grain‐size and lower organic contents are recorded. These glacial to interglacial differences in mineralogy, grain‐size distribution and organic content clearly show the impact of climatically controlled sea‐level fluctuations on the sedimentation patterns of the northern slope of Little Bahama Bank. The coarser deposits (ii) occur mainly at the transitions from glacial to interglacial and interglacial to glacial stages, and are interpreted as redeposition events, indicating a direct link between sediment properties (changes in mineralogy, grain‐size distribution, variations in organic contents) and sea‐level fluctuations. Changes in hydrostatic pressure and the wave base position during sea‐level changes are proposed to have triggered these large‐scale sediment redepositions.
Particle shape: a review and new methods of characterization and classification
Authors: BLOTT SIMON J. , PYE KENNETH
Published: September 2007

Shape is a fundamental property of all objects, including sedimentary particles, but it remains one of the most difficult to characterize and quantify for all but the simplest of shapes. Despite a large literature on the subject, there remains widespread confusion regarding the meaning and relative value of different measures of particle shape. This paper re‐examines the basic concepts of particle shape and suggests a number of new and modified methods which are widely applicable to a range of sedimentological problems; it is shown that the most important aspects of particle form are represented by the I/L ratio (elongation ratio) and S/I ratio (flatness ratio). A combination of these two ratios can be used to classify particles in terms of 25 form classes. A method of obtaining a quantitative measure of particle roundness using simple image analysis software is described, and a new visual roundness comparator is presented. It is recommended that measurements of both roundness and circularity (a proxy measure of sphericity) are made on grain images in three orthogonal orientations and average values calculated for each particle. A further shape property, irregularity, is defined and a classification scheme proposed for use in describing and comparing irregular or branching sedimentary particles such as chert and coral.
Rheological behaviour of the crust in Southern Apennine (Italy): results from a thermal and seismological study
Authors: Solaro Giuseppe , Tizzani Pietro , Milano Girolamo , Pauselli Cristina
Published: September 2007

To add information on the brittle/ductile transition of the Southern Apennine, we investigated a rheological profile of the crust along a WSW–ENE‐oriented cross‐section running from Neapolitan Volcanic Zone to Apulia foreland. The rheological model was obtained computing a thermal modelling and constrained by a relocalization of earthquakes of the area. Results show that the area is characterized by horizontal rheological variations, with two horizons interlayered with ductile horizons, that are quite predominant with respect to vertical ones. The horizontal stratification of lithospheric rheology has important geodynamic consequence and could provide new insights to better understand the tectonic processes which have played a major role to construct the Southern Apennine belt. Results of this study suggested that well‐constrained rheological models, built integrating information from both relocated earthquakes and thermal state, could give important hints on the mechanical behaviour of the crust and its related tectonic processes.
Modelling the lithospheric rheology control on the Cretaceous rifting in West Antarctica
Authors: Bonini Marco , Corti Giacomo , Ventisette Chiara Del , Manetti Piero , Mulugeta Genene , Sokoutis Dimitrios
Published: September 2007

Small‐scale analogue models were used to investigate the process of Cretaceous orthogonal extension in the West Antarctic Rift System. The models considered the transition from the East Antarctic Craton to a weaker lithosphere, and the results support previous hypotheses about the strong control exerted by lateral variations in lithospheric structures on the process of extension. Strain was mostly accommodated at the boundary between the two types of lithosphere, with a relative uplift of the cratonic block which remained essentially undeformed. Conversely, the weaker lithosphere showed wide‐rifting style geometry, locally associated with core complex‐like structures. In agreement with the natural prototype, this tectonic scenario led to a long‐lasting extension without continental break‐up, and to the absence of relevant surface magmatism.
Conditional oxidative stress responses in the Arabidopsis photorespiratory mutant cat2 demonstrate that redox state is a key modulator of daylength‐dependent gene expression, and define photoperiod as a crucial factor in the regulation of H2O2‐induced cell death
Authors: Queval Guillaume , Issakidis‐Bourguet Emmanuelle , Hoeberichts Frank A. , Vandorpe Michaël , Gakière Bertrand , Vanacker Hélène , Miginiac‐Maslow Myroslawa , Van Breusegem Frank , Noctor Graham
Published: September 2007

Photorespiration is a light‐dependent source of H2O2 in the peroxisomes, where concentrations of this signalling molecule are regulated by catalase. Growth of Arabidopsis knock‐out mutants for CATALASE2 (cat2) in ambient air caused severely decreased rosette biomass, intracellular redox perturbation and activation of oxidative signalling pathways. These effects were absent when cat2 was grown at high CO2 levels to inhibit photorespiration, but were re‐established following a subsequent transfer to air. Growth of cat2 in air at different daylengths revealed that photoperiod is a critical determinant of the oxidative stress response. Decreased growth was observed in 8‐h, 12‐h and 16‐h photoperiods, but lesion development was dependent on long days. Experiments at different light fluence rates showed that cell death in cat2 was linked to long days and not to total light exposure or the severity of oxidative stress. Perturbed intracellular redox state and oxidative signalling pathway induction were more prominent in short days than in long days, as evidenced by glutathione status and induction of defence genes and oxidative stress‐responsive transcripts. Similar daylength‐dependent effects were observed in the response of mature plants transferred from short days in high CO2 conditions to ambient air conditions. Prior growth of plants with short days in air alleviated the cat2 cell‐death phenotype in long days. Together, the data reveal the influence of photoperiodic events on redox signalling, and define distinct photoperiod‐dependent strategies in the acclimation versus cell‐death decision in stress conditions.