bluuebunny/crossref_metadata_2025 huggingface dataset:
Purification and properties of glutamate-phenylpyruvate aminotransferase from the ruminal protozoan Entodinium caudatum
Authors: Amin Md. Ruhul , Onodera Ryoji , Khan R. Islam , Wallace R. John , Newbold C. Jamie
Published: September 2004

Entodinium species are important in catabolic protein metabolism by the mixed ruminal microbial population. This study was conducted to purify, and investigate properties of one of the enzymes involved in amino acid metabolism by Entodinium caudatum, glutamate-phenylpyruvate aminotransferase (GPA; EC 2.6.1.64). GPA was purified 74-fold from a cell-free extract by ammonium sulfate precipitation and column chromatography with phenyl-superose, DEAE-Toyopearl 650M, Sephacryl S-100 HR, and Sephadex G-100. The molecular mass of GPA was estimated by SDS–PAGE to be 65.0 kDa. The optimum pH was 6.0 and it was found to be reactive over a wide range of pH from 5.0 to 10.5. Maximum activity of GPA occurred at 45°C and the activity declined at temperatures over 55°C. GPA was stable below 60°C. Aminooxyacetate and phenylhydrazine were highly inhibitory, and SDS, EDTA, and some heavy metal ions also inhibited activity. The purification and characterisation of the enzyme will help to isolate the gene and ultimately to understand the role of GPA in both anabolic and catabolic amino acid metabolism by Entodinium caudatum.
The accuracy of dual energy X-ray absorptiometry (DXA), weight, and P2 back fat to predict half-carcass and primal-cut composition in pigs within and across research experiments
Authors: Suster D. , Leury B. J. , Hofmeyr C. D. , D'Souza D. N. , Dunshea F. R.
Published: September 2004

A Hologic QDR4500A dual energy X-ray absorptiometer (DXA) was used to measure body composition in 199 half-carcasses ranging from 15 to 48 kg. Half-carcasses were from animals of mixed sex and of either Large White × Landrace or Large White × Landrace × Duroc descent. Half-carcasses were selected from 5 different experiments to evaluate DXA accuracy within and across experiments. Values determined by DXA including total tissue mass, fat tissue mass, lean tissue mass, and bone mineral content, for the half-carcass and the shoulder, loin, belly, and ham primal cuts were evaluated by comparison with manually dissected composition. Relationships between manually dissected values and measurements of weight and backfat at the P2 site were also evaluated. Manually dissected values were strongly related to DXA-derived values, more so than with weight and P2 or a combination of both, particularly in the measurement of fat composition. In contrast to estimates derived from weight and P2, DXA-derived estimates remained accurate even when between-experiment variation was included. However, because DXA estimates were different from manually dissected values, they would need to be adjusted with the use of appropriate regression equations to correct the in-built algorithms. These results demonstrate the efficacy of DXA as a non-destructive method for determining the composition of the half-carcass and primal cuts, and its greater precision than current routinely used methods.
Development of DNA fingerprinting keys for discrimination of Cicer echinospermum (P.H. Davis) accessions using AFLP markers
Authors: Shan Fucheng , Clarke Heather , Yan Guijun , Plummer Julie A. , Siddique Kadambot H. M.
Published: September 2004

To test the hypothesis that DNA markers associated with specific genetic make-up can be detected and used to discriminate genotypes, amplified fragment length polymorphism (AFLP) markers were produced for 14 accessions in Cicer echinospermum, a close relative of Cicer arietinum (chickpea). Six selective amplification primer combinations produced high polymorphism with average polymorphic loci of 77.2%. The polymorphism detected in this study enabled fingerprinting keys to be established to discriminate accessions within C. echinospermum. Results showed that molecular analysis using AFLP was a good and reliable technique to differentiate C. echinospermum accessions and to reconstruct phylogenetic relationships between them, which could help parental selection in chickpea improvement programs.
Predictors of pregnancy and postpartum haemoglobin concentrations in low-income women
Authors: Bodnar Lisa M , Siega-Riz Anna Maria , Arab Lenore , Chantala Kim , McDonald Thad
Published: September 2004

Objective:

Pregnancy and postpartum iron status is of great public health importance, yet few studies have examined predictors of haemoglobin (Hb) concentration during this time. We identified predictors of Hb from 24 weeks' gestation until delivery and from 4 to 25 weeks postpartum.

Design:

Blood was drawn as many as four times during care: at the initial visit, at 24–29 weeks' gestation, at delivery and postpartum. A longitudinal, multivariable linear regression model was used to predict Hb concentration.

Setting:

A public health clinic in Raleigh, North Carolina.

Subjects:

n= 520 women who participated in the Iron Supplementation Study.

Results:

Hb concentration at the previous blood draw, short stature, non-Hispanic white ethnicity/race, > 12 years of education and smoking were positive predictors of pregnancy and postpartum Hb concentrations. Iron supplement use was a positive predictor, while inadequate weight gain and severe nausea/vomiting were negative predictors of gestational Hb. A high infant birth weight and postpartum haemorrhage were negative predictors of postpartum Hb. Pre-pregnancy body mass index had a slight positive relationship with gestational Hb, but had a strong negative relationship with postpartum Hb. The longitudinal model also confirmed the typical pattern of gestational Hb concentration. As the number of weeks between the initial visit and the 24- to 29-week visit increased, Hb at 24–29 weeks' gestation decreased. As gestational age increased from 24 weeks until delivery, Hb concentration increased as well.

Conclusions:

The predictors identified here could be used in clinical settings to target high–risk women for intervention.
Plasma levels of six carotenoids in nine European countries: report from the European Prospective Investigation into Cancer and Nutrition (EPIC)
Authors: Al-Delaimy Wael K , van Kappel Anne Linda , Ferrari Pietro , Slimani Nadia , Steghens Jean-Paul , Bingham Sheila , Johansson Ingegerd , Wallström Peter , Overvad Kim , Tjønneland Anne , Key Tim J , Welch Ailsa A , Bueno-de-Mesquita H Bas , Peeters Petra HM , Boeing Heiner , Linseisen Jakob , Clavel-Chapelon Françloise , Guibout Catherine , Navarro Carmen , Quirós Jose Ramón , Palli Domenico , Celentano Egidio , Trichopoulou Antonia , Benetou Vassiliki , Kaaks Rudolf , Riboli Elio
Published: September 2004

Background:

In addition to their possible direct biological effects, plasma carotenoids can be used as biochemical markers of fruit and vegetable consumption for identifying diet–disease associations in epidemiological studies. Few studies have compared levels of these carotenoids between countries in Europe.

Objective:

Our aim was to assess the variability of plasma carotenoid levels within the cohort of the European Prospective Investigation into Cancer and Nutrition (EPIC).

Methods:

Plasma levels of six carotenoids – α-carotene, β-carotene, β-cryptoxanthin, lycopene, lutein and zeaxanthin – were measured cross-sectionally in 3043 study subjects from 16 regions in nine European countries. We investigated the relative influence of gender, season, age, body mass index (BMI), alcohol intake and smoking status on plasma levels of the carotenoids.

Results:

Mean plasma level of the sum of the six carotenoids varied twofold between regions (1.35μmoll−1for men in Malmö, Sweden vs. 2.79μmoll−1for men in Ragusa/Naples, Italy; 1.61μmoll−1for women in The Netherlands vs. 3.52μmoll−1in Ragusa/Naples, Italy). Mean levels of individual carotenoids varied up to fourfold (α-carotene: 0.06μmoll−1for men in Murcia, Spain vs. 0.25μmoll−1for vegetarian men living in the UK). In multivariate regression analyses, region was the most important predictor of total plasma carotenoid level (partialR2=27.3%), followed by BMI (partialR2=5.2%), gender (partialR2=2.7%) and smoking status (partialR2=2.8%). Females had higher total carotenoid levels than males across Europe.

Conclusions:

Plasma levels of carotenoids vary substantially between 16 different regions in Italy, Greece, Spain, France, Germany, the UK, Sweden, Denmark and The Netherlands. Compared with region of residence, the other demographic and lifestyle factors and laboratory measurements have limited predictive value for plasma carotenoid levels in Europe.
Accuracy of self-reported waist and hip measurements in 4492 EPIC–Oxford participants
Authors: Spencer Elizabeth A , Roddam Andrew W , Key Timothy J
Published: September 2004

Objective:

To assess the accuracy of self-reported waist and hip circumferences and the waist-to-hip ratio (WHR) by comparison with measured waist and hip circumferences and WHR in a sample of middle-aged men and women.

Design:

Analysis of measured and self-reported waist and hip data from participants in the Oxford cohort of the European Prospective Investigation into Cancer and Nutrition (EPIC–Oxford).

Participants:

Four thousand four hundred and ninety-two British men and women aged 35–76 years.

Results:

Spearman's rank correlation coefficients between measured and self-reported waist, hip and WHR were 0.80, 0.74 and 0.44, respectively, for men and 0.83, 0.86 and 0.62 for women. Waist was underestimated, on average, by 3.1 (standard deviation (SD) 5.6) cm in men and 1.9 (SD 5.4) cm in women. The extent of underestimation was greater in participants with larger waists, older participants and women with greater body mass index (BMI). Hip was underestimated by a mean of 1.8 (SD 4.9) cm in men and 1.2 (SD 4.5) cm in women; the extent of underestimation was greater in participants with larger hip circumference and older participants. On average, WHR was underestimated by less than 2% by men and women; the extent of underestimation was greater among those with larger WHR, older people and those with greater BMI. Using self-reported values, the proportion of classification to the correct tertile was over 65% for waist and hip measurements. For WHR this proportion was 50% among men and 60% among women.

Conclusions:

Self-reported waist and hip measurements in EPIC–Oxford are sufficiently accurate for identifying relationships in epidemiological studies.
Prevalence and predictors of food insecurity among low-income households in Los Angeles County
Authors: Furness Bruce W , Simon Paul A , Wold Cheryl M , Asarian-Anderson Johanna
Published: September 2004

Objectives:

To assess the prevalence and identify the predictors of food insecurity among households in Los Angeles County with incomes below 300% of the federal poverty level.

Methods:

The Six-Item Short Form of the US Department of Agriculture's Household Food Security Scale was used as part of a 1999 county-wide, population-based, telephone survey.

Results:

The prevalence of food insecurity was 24.4% and was inversely associated with household income. Other independent predictors of food insecurity included the presence of children in the household (odds ratio (OR) 1.7, 95% confidence interval (CI) 1.2–2.3) and a history of homelessness in the past five years (OR 5.6, 95% CI 3.4–9.4).

Conclusion:

Food insecurity is a significant public health problem among low–income households in Los Angeles County. Food assistance programmes should focus efforts on households living in and near poverty, those with children, and those with a history of homelessness.
Sources and credibility of nutrition information among black urban South African women, with a focus on messages related to obesity
Authors: Charlton KE , Brewitt P , Bourne LT
Published: September 2004

Objectives:

(1) To identify the major sources of nutrition information, and the perceived credibility thereof, among urban black South African women; and (2) to determine the level of knowledge regarding nutrition, particularly regarding the topic of obesity.

Design:

A cross–sectional descriptive study that was both qualitative (focus groups) and quantitative (individual questionnaires). Three hundred and ninety–four black women aged 17–49 years were conveniently sampled from the Western Cape and Gauteng provinces in South Africa.

Methods:

Four focus groups were held with 39 women to identify common themes relating to nutrition knowledge. Based on these data, a questionnaire instrument was developed and administered to 394 women by trained fieldworkers.

Results:

The most frequently encountered source of nutrition information was the media, particularly the radio and TV (73.4% and 72.1% of subjects, respectively, obtained information from this source in the past year), followed by family/friends (64.6%). Despite only 48.5% of subjects having received nutrition information from a health professional, this was the most highly credible information source. Factors being most influential in choice of foods were taste, preferences of the rest of the family, and price. A lack of knowledge on certain aspects of nutrition was identified, as well as misconceptions regarding diet and obesity.

Conclusion:

To improve nutrition knowledge and the effectiveness of nutrition education activities in South Africa, it is recommended that health and nutrition educators become more actively involved with the training of health professionals, particularly those engaged in delivery of services at primary care level, and in turn encourage health professionals to engage more with media sources. Nutrition messages delivered from health professionals via the media will enable public exposure to nutrition information which is not only easily accessible but also perceived to be highly credible.
Full-term, peri-urban South African infants under 6 months of age are at risk for early-onset anaemia
Authors: Sibeko LN , Dhansay MA , Charlton KE , Johns T , Van Stuijvenberg ME , Gray-Donald K
Published: September 2004

Objective:

There is a paucity of data on the micronutrient status of low-income, lactating South African women and their infants under 6 months of age. The aim of this study was to elucidate the level of anaemia and vitamin A deficiency (VAD) in peri-urban breast-feeding women and their young infants.

Design:

Cross-sectional study including anthropometric, biochemical and infant feeding data.

Setting:

Peri-urban settlement in Cape Town, South Africa.

Subjects:

Breast-feeding women (n= 113) and their infants (aged 1–6 months) attending a peri-urban clinic.

Results:

Mean (standard deviation (SD)) haemoglobin (Hb) of the lactating mothers was 12.4 (1.3) gdl−1, with 32% found to be anaemic (Hb < 12 g dl−1). Maternal serum retinol was 49.8 (SD 13.3) μg dl−1, with 4.5% VAD. Using breast milk, mean (SD) retinol concentration was found to be 70.6 (24.6) μg dl−1and 15.7 (8.3) μg/g milk fat, with 13% below the cut-off level of <8μg/g fat. There was no correlation found between breast milk retinol and infant serum retinol.Z-scores (SD) of height-for-age, weight-for-age and weight-for-height were –0.69 (0.81), 0.89 (1.01) and 1.78 (0.83), respectively. Mean (SD) infant Hb was 10.9 (1.1) g dl−1, with the prevalence of anaemia being 50%, 33% and 12% using Hb cut-offs below 11 g dl−1, 10.5 g dl−1and 9.5 g dl−1, respectively. Mean (SD) infant serum retinol was 26.9 (7.2) μg dl−1, with 10% being VAD. None of the infants was exclusively breast-fed, 22% were predominantly breast-fed and 787percnt; received complementary (mixed) breast-feeding. Thirty-two per cent of infants received weaning foods at an exceptionally young age (≤1 month old).

Conclusion:

A high rate of anaemia is present in lactating women residing in resource-poor settings. Moreover, their seemingly healthy infants under 6 months of age are at an elevated risk of developing early-onset anaemia and at lower risk of VAD.
Invited Review: Toxicoproteomics: Proteomics Applied to Toxicology and Pathology
Authors: Wetmore Barbara A. , Merrick B. Alex
Published: September 2004

Global measurement of proteins and their many attributes in tissues and biofluids defines the field of proteomics. Toxicoproteomics, as part of the larger field of toxicogenomics, seeks to identify critical proteins and pathways in biological systems that are affected by and respond to adverse chemical and environmental exposures using global protein expression technologies. Toxicoproteomics integrates 3 disciplinary areas: traditional toxicology and pathology, differential protein and gene expression analysis, and systems biology. Key topics to be reviewed are the evolution of proteomics, proteomic technology platforms and their capabilities with exemplary studies from biology and medicine, a review of over 50 recent studies applying proteomic analysis to toxicological research, and the recent development of databases designed to integrate -Omics technologies with toxicology and pathology. Proteomics is examined for its potential in discovery of new biomarkers and toxicity signatures, in mapping serum, plasma, and other biofluid proteomes, and in parallel proteomic and transcriptomic studies. The new field of toxicoproteomics is uniquely positioned toward an expanded understanding of protein expression during toxicity and environmental disease for the advancement of public health.
An Effect of Context on Whether Memory for Initial Position Exhibits a FröHlich Effect or an Onset Repulsion Effect
Authors: Hubbard Timothy L. , Motes Michael A.
Published: September 2004

Memory for the initial and final positions of moving targets was examined. When targets appeared adjacent to the boundary of a larger enclosing window, memory for initial position exhibited a Fröhlich effect (i.e., a displacement forward), and when distance of initial position from the boundary increased, memory for initial position exhibited a smaller Fröhlich effect or an onset repulsion effect (i.e., a displacement backward). When targets vanished adjacent to the boundary of a larger enclosing window, memory for final position was displaced backward, and when distance of final position from the boundary increased, memory for final position did not exhibit significant displacement. These patterns differed from previously reported displacements of initial and final positions of targets presented on a blank background. Possible influences of attention and extrapolation of trajectory on whether memory for initial position exhibits a Fröhlich effect or an onset repulsion effect and on backward displacement in memory for final position are discussed.
Does Binocular Disparity or Familiar Size Information Override Effects of Relative Size on Judgements of Time to Contact?
Authors: DeLucia Patricia R.
Published: September 2004

Previous studies indicate that non-tau sources of depth information, such as pictorial depth cues, can influence judgements of time to contact (TTC). The effect of relative size on such judgements, the size-arrival effect, is particularly robust. However, earlier studies of the size-arrival effect did not include binocular disparity or familiar size information. The effects of these cues on relative TTC judgements were measured. Results suggested that disparity can eliminate the size-arrival effect but that the amount of disparity needed to do so is greater than typical stereoacuity thresholds. In contrast, familiar size eliminated the size-arrival effect even when disparity information was not available. Furthermore, disparity contributed more to performance when familiar size was present than when it was absent. Consistent with previous studies, TTC judgements were influenced by multiple sources of information. The present results suggested further that familiar size is one such source of information and that familiar size moderates the influence of binocular disparity information.
Do Taxes Lower Employment in the Third World? Evidence from Personal Service Firms in Pre-Debt-Crisis Brazil
Authors: Cohn Samuel , Rainwater Elizabeth , Bradshaw Matt
Published: September 2004

In most nations, developed and undeveloped alike, employers' associations advocate tax cuts as a strategy for increasing employment. The literature on public finance and Third World taxation has been sceptical of these claims, although a small literature within economics favouring tax cuts does exist. Neither side provides compelling empirical evidence for or against tax relief as a tool to generate employment. The present paper provides such evidence for Brazilian restaurants, hotels and barber/beauty shops in the period 1940–1980. After controls are introduced for the size of potential markets and the impact of other non-tax costs, tax rates have virtually no effect on employment. This is because many Third World firms are characterized by a constellation of forces that theoretically minimize the link between taxation and employment. Third World governments that seek to increase employment in strategic industries would be better off using their funds to create programmes designed to stimulate employment proactively.
Middle Managers, the New Organizational Ideology and Corporate Restructuring: Comparing Japanese and Anglo-American Management Systems
Authors: McCann Leo , Hassard John , Morris Jonathan
Published: September 2004

Middle managers are facing major workplace pressures in an era of widespread corporate and public sector restructuring in Japan, USA and UK. This paper, based on interviews with senior/HR managers and middle managers in 30 large organizations, suggests that middle managers today face heavy workloads and limited promotion prospects. More significantly, the central task of middle management is changing from managing subordinates in hierarchies towards managing projects in flattened organizations. These changes are in accordance with a new organizational ideology that continues to influence change in public and private organizations in co-ordinated or free market economies. While this ideology has spread rapidly, it has not managed to achieve hegemony. Organizations can be difficult to change and bureaucratic elements will persist despite the changes. The Japanese co-ordinated model and the US and UK free market model are both subject to similar pressures, but the actual organizational changes work themselves out in different ways because of differing institutional arrangements.
Cortical Gray Matter Volumes are Associated with Subjective Responses to Cocaine Infusion
Authors: Bartzokis George , Beckson Mace , Lu Po H. , Edwards Nancy , Rapoport Ruth , Bridge Peter , Mintz Jim
Published: September 2004

We analyzed the relationship between cocaine‐induced euphoria and measures of frontal and temporal gray matter volumes in eleven cocaine‐dependent (CD) patients who underwent magnetic resonance imaging (MRI). Self‐reported ratings of the intensity of euphoric response to cocaine infusion were obtained from the CD subjects at 3, 10, and 30 minutes after cocaine infusion. Significant positive correlation between frontal and temporal cortical gray matter volume and the intensity of euphoria was observed at 10 minutes after IV cocaine. The data suggest that frontal and temporal lobe gray matter volume is associated with some of the reinforcing effects of cocaine. Given the well‐established negative linear relationship between cortical gray matter volume and age, cortical gray matter volume may be a marker for the neurobiological substrate of the age‐related reduction in addiction rates.
Chapter 2. Methods used for the systematic literature search and for the review of relevance, quality, and evidence of studies
Authors: Alexanderson Kristina , Norlund Anders
Published: September 2004

Published scientific studies on the topics of sick leave, disability pension, and sick-listing practices were searched for, reviewed, and compiled for this report. The approach used reflects in many ways the criteria for systematic literature reviews in health care often associated with the Cochrane Collaboration (1). The area addressed by the literature review - sick leave - requires, however, some specific review criteria (see below).
Chapter 4. Methodological aspects in sickness-absence research
Authors: Hensing Gunnel
Published: September 2004

Several methodological aspects concerning research on sickness absence and disability pension are noteworthy, including: empirical research is being conducted within many different disciplines using various study designs; progress in theory development has been slow and weak; several outcome measures are used; terminology varies widely; and comparative research is difficult to conduct since insurance systems differ over time and among nations and employers.
Chapter 6. Sickness absence due to back and neck disorders
Authors: Hansson Tommy , Jensen Irene
Published: September 2004

The scientific evidence on the causes for sick leave attributed to back and neck disorders was reviewed. Categories were established for acute, recurring, and chronic problems based on the duration of the sick leave period. Forty-eight articles were found to be relevant, whereof two were of high quality and 26 were of medium or low quality. Quality was assessed exclusively in relation to the aim of this systematic review. The results reveal limited published research on causes for sick leave from back and neck disorders. The generalisability of the findings is also limited since most of the subjects were men and employees in manufacturing industries. Women, white-collar workers, employees in the public sector (care, social services, schools, etc) were underrepresented in the studies. Hence, these groups and areas should be studied further to verify conclusions and enhance knowledge about the causes for sick leave from back and neck disorders. The following factors were found to have consistent, but limited, support as regards their influence on the risk for sick leave due to back and neck disorders: (a) heavy physical workload, bent or twisted working position, and low work satisfaction increases the risk for short-term and long-term sick leave; (b) specific back diagnoses and previous sick leave due to back disorders increases the risk for short-term and long-term sick leave; (c) female gender, smoking, exposure to vibration, and deficient social support were not found to significantly increase the risk for short-term and long-term sick leave; (d) self-reported pain and functional impairments were associated with a high risk for long-term sick leave; (e) longer employment periods reduced the risk for short-term sick leave; (f) perceived demands at work did not influence short-term sick leave; (g) female gender and higher age increases the risk for disability pension.
Chapter 8. Sick leave due to coronary artery disease or stroke
Authors: Perk Joep , Alexanderson Kristina
Published: September 2004

The assessment of the literature on sick-leave with cardiovascular diseases include only studies with sufficient scientific quality. These studies describe sick leave following stroke, myocardial infarction, coronary artery bypass grafting (CABG), or percutaneous coronary intervention (PCI). We found limited scientific evidence for the following results: After stroke, more than half of the patients of working age returned to work (RTW) during the first year following onset (higher rate for the younger patients). The consequences of brain damage, e.g. impaired ADL ability or cognitive capacity, play an important role in this respect. Also after myocardial infarction most patients RTW. PCI is a milder coronary artery intervention than CABG and RTW is more rapid. However, in the long run there are no differences in sick leave. People at higher ages or with physically demanding jobs return to work to a lesser degree. An international comparison shows that the duration of sick leave due to these conditions in Sweden is longer than in other countries although there is no scientific evidence to support this practice. It appears that the interest in research on sick leave in patients with cardiovascular diseases has waned in recent years. Developments in acute cardiological care should inspire renewed scientific involvement in this area of research.
Chapter 9. Consequences of being on sick leave
Authors: Vingård Eva , Alexanderson Kristina , Norlund Anders
Published: September 2004

The possible consequences of sick leave can be measured at different levels in society. This chapter focuses on the consequences from the perspective of the sick-listed individual. Sick leave may have both positive and negative consequences for the individual, e.g. regarding disease, health, working life, social life, lifestyle, and emotional aspects. Some of these factors have been investigated in different studies. However, scientific evidence is insufficient since there are too few studies on the consequences of sickness absence and disability pension. The lack of relevant studies is the most striking observation from the review of studies on the consequences of being sick listed.
Chapter 10. Sickness presence
Authors: VingÅrd Eva , Alexanderson Kristina , Norlund Anders
Published: September 2004

The term "sickness presence'' is used to describe situations where the ability to work is impaired due to disease, but yet the person goes to work. A problem is that the term "sickness presence'' implies that being present at work is something exceptional if a person is sick. Most people diagnosed with a disease or disorder do, however, go to work and are not sick listed. Furthermore, the term "sickness presence'' is rather diffuse, and it would be beneficial if one or several more specific terms could be used. The current body of scientific literature does not provide sufficient evidence to draw conclusions on the consequences of sickness presence.
Chapter 11. Physicians' sick-listing practices
Authors: Wahlström Rolf , Alexanderson Kristina
Published: September 2004

Physicians' sick-listing practices have been studied to a very limited extent. There is limited scientific evidence that physicians perceive sick-listing duties to be difficult and problematic, regarding both the medical and the insurance-related aspects. There is limited scientific evidence also that quality is often deficient in the sickness certificates issued by physicians. This may affect case management at the local insurance office. There is insufficient scientific evidence to explain the differences in physicians' sick-listing patterns. The effects on patients are also insufficiently studied.
Eppur si muove?
Authors: Ludwig-Mayerhofer Wolfgang , Wroblewski Angela
Published: September 2004

Current debates about activation policies focus only to a very limited degree on continental or conservative welfare states, as countries like Austria and Germany are usually assumed to exhibit a low degree of activation. However, active labour market policies have a long tradition in both countries. This paper analyses the development of active labour market policy in Germany and Austria during the last two decades with special emphasis on recent reform attempts. Against this background, the potential outcome of the central reforms is discussed. In spite of claims to ‘modernise’ the welfare system and labour market policies, current developments work mainly in the direction of curtailing benefits and rights of the unemployed.
The mechanism of spindle assembly
Authors: Gruss Oliver J. , Vernos Isabelle
Published: September 2004

Recent work has provided new insights into the mechanism of spindle assembly. Growing evidence supports a model in which the small GTPase Ran plays a central role in this process. Here, we examine the evidence for the existence of a RanGTP gradient around mitotic chromosomes and some controversial data on the role that chromosomes play in spindle assembly. We review the current knowledge on the Ran downstream targets for spindle assembly and we focus on the multiple roles of TPX2, one of the targets of RanGTP during cell division.
CD44 modulates Smad1 activation in the BMP-7 signaling pathway
Authors: Peterson Richard S. , Andhare Roma A. , Rousche Kathleen T. , Knudson Warren , Wang Weihua , Grossfield Jami B. , Thomas Raymond O. , Hollingsworth Robert E. , Knudson Cheryl B.
Published: September 2004

Bone morphogenetic protein 7 (BMP-7) regulates cellular metabolism in embryonic and adult tissues. Signal transduction occurs through the activation of intracellular Smad proteins. In this paper, using a yeast two-hybrid screen, Smad1 was found to interact with the cytoplasmic domain of CD44, a receptor for the extracellular matrix macromolecule hyaluronan. Coimmunoprecipitation experiments confirmed the interaction of Smad1 with full-length CD44—interactions that did not occur when CD44 receptors truncated within the cytoplasmic domain were tested. Chondrocytes overexpressing a truncated CD44 on a background of endogenous full-length CD44 no longer exhibited Smad1 nuclear translocation upon BMP-7 stimulation. Further, pretreatment of chondrocytes with Streptomyces hyaluronidase to disrupt extracellular hyaluronan–cell interactions inhibited BMP-7–mediated Smad1 phosphorylation, nuclear translocation of Smad1 or Smad4, and SBE4–luciferase reporter activation. These results support a functional link between the BMP signaling cascade and CD44. Thus, changes in hyaluronan–cell interactions may serve as a means to modulate cellular responsiveness to BMP.
STAT3 noncell-autonomously controls planar cell polarity during zebrafish convergence and extension
Authors: Miyagi Chiemi , Yamashita Susumu , Ohba Yusuke , Yoshizaki Hisayoshi , Matsuda Michiyuki , Hirano Toshio
Published: September 2004

Zebrafish signal transducer and activator of transcription 3 (STAT3) controls the cell movements during gastrulation. Here, we show that noncell-autonomous activity of STAT3 signaling in gastrula organizer cells controls the polarity of neighboring cells through Dishevelled-RhoA signaling in the Wnt-planar cell polarity (Wnt-PCP) pathway. In STAT3-depleted embryos, although all the known molecules in the Wnt-PCP pathway were expressed normally, the RhoA activity in lateral mesendodermal cells was down-regulated, resulting in severe cell polarization defects in convergence and extension movements identical to Strabismus-depleted embryos. Cell-autonomous activation of Wnt-PCP signaling by ΔN-dishevelled rescued the defect in cell elongation, but not the orientation of lateral mesendodermal cells in STAT3-depleted embryos. The defect in the orientation could be rescued by transplantation of shield cells having noncell-autonomous activity of STAT3 signaling. These results suggest that the cells undergoing convergence and extension movement may sense the gradient of signaling molecules, which are expressed in gastrula organizer by STAT3 and noncell-autonomously activate PCP signaling in neighboring cells during zebrafish gastrulation.
Nuclear export of OLIG2 in neural stem cells is essential for ciliary neurotrophic factor–induced astrocyte differentiation
Authors: Setoguchi Takao , Kondo Toru
Published: September 2004

Neural stem cell (NSC) differentiation is precisely controlled by a network of transcription factors, which themselves are regulated by extracellular signals (Bertrand et al., 2002; Shirasakiand and Pfaff, 2002). One way that the activity of such transcription factors is controlled is by the regulation of their movement between the cytosol and nucleus (Vandromme et al., 1996. Lei and Silver, 2002). Here we show that the basic helix–loop–helix transcription factor OLIG2, which has been shown to be required for motor neuron and oligodendrocyte development, is found in the cytoplasm, but not the nucleus, of astrocytes in culture and of a subset of astrocytes in the subventricular zone. We demonstrate that the accumulation of OLIG2 in the nucleus of NSCs blocks the CNTF-induced astrocyte differentiation and that the translocation of OLIG2 to the cytoplasm is promoted by activated AKT. We propose that the AKT-stimulated export of OLIG2 from the nucleus of NSCs is essential for the astrocyte differentiation.
Conversion of ES cells to columnar epithelia by hensin and to squamous epithelia by laminin
Authors: Takito Jiro , Al-Awqati Qais
Published: September 2004

Single-layered epithelia are the first differentiated cell types to develop in the embryo, with columnar and squamous types appearing immediately after blastocyst implantation. Here, we show that mouse embryonic stem cells seeded on hensin or laminin, but not fibronectin or collagen type IV, formed hemispheric epithelial structures whose outermost layer terminally differentiated to an epithelium that resembled the visceral endoderm. Hensin induced columnar epithelia, whereas laminin formed squamous epithelia. At the egg cylinder stage, the distal visceral endoderm is columnar, and these cells begin to migrate anteriorly to create the anterior visceral endoderm, which assumes a squamous shape. Hensin expression coincided with the dynamic appearance and disappearance of columnar cells at the egg cylinder stage of the embryo. These expression patterns, and the fact that hensin null embryos (and those already reported for laminin) die at the onset of egg cylinder formation, support the view that hensin and laminin are required for terminal differentiation of columnar and squamous epithelial phenotypes during early embryogenesis.
Physiological and Microfluorometric Studies of Reduction and Clearance of Retinal in Bleached Rod Photoreceptors
Authors: Tsina Efthymia , Chen Chunhe , Koutalos Yiannis , Ala-Laurila Petri , Tsacopoulos Marco , Wiggert Barbara , Crouch Rosalie K. , Cornwall M. Carter
Published: September 2004

The visual cycle comprises a sequence of reactions that regenerate the visual pigment in photoreceptors during dark adaptation, starting with the reduction of all-trans retinal to all-trans retinol and its clearance from photoreceptors. We have followed the reduction of retinal and clearance of retinol within bleached outer segments of red rods isolated from salamander retina by measuring its intrinsic fluorescence. Following exposure to a bright light (bleach), increasing fluorescence intensity was observed to propagate along the outer segments in a direction from the proximal region adjacent to the inner segment toward the distal tip. Peak retinol fluorescence was achieved after ∼30 min, after which it declined very slowly. Clearance of retinol fluorescence is considerably accelerated by the presence of the exogenous lipophilic substances IRBP (interphotoreceptor retinoid binding protein) and serum albumin. We have used simultaneous fluorometric and electrophysiological measurements to compare the rate of reduction of all-trans retinal to all-trans retinol to the rate of recovery of flash response amplitude in these cells in the presence and absence of IRBP. We find that flash response recovery in rods is modestly accelerated in the presence of extracellular IRBP. These results suggest such substances may participate in the clearance of retinoids from rod photoreceptors, and that this clearance, at least in rods, may facilitate dark adaptation by accelerating the clearance of photoproducts of bleaching.
Regulation of Ca2+ Sparks by Ca2+ and Mg2+ in Mammalian and Amphibian Muscle. An RyR Isoform-specific Role in Excitation–Contraction Coupling?
Authors: Zhou Jingsong , Launikonis Bradley S. , Ríos Eduardo , Brum Gustavo
Published: September 2004

Ca2+ and Mg2+ are important mediators and regulators of intracellular Ca2+ signaling in muscle. The effects of changes of cytosolic [Ca2+] or [Mg2+] on elementary Ca2+ release events were determined, as functions of concentration and time, in single fast-twitch permeabilized fibers of rat and frog. Ca2+ sparks were identified and their parameters measured in confocal images of fluo-4 fluorescence. Solutions with different [Ca2+] or [Mg2+] were rapidly exchanged while imaging. Faster and spatially homogeneous changes of [Ca2+] (reaching peaks >100 μM) were achieved by photolysing Ca NP-EGTA with laser flashes. In both species, incrementing cytosolic [Ca2+] caused a steady, nearly proportional increase in spark frequency, reversible upon [Ca2+] reduction. A greater change in spark frequency, usually transient, followed sudden increases in [Ca2+] after a lag of 100 ms or more. The nonlinearity, lag, and other features of this delayed effect suggest that it requires increase of [Ca2+] inside the SR. In the frog only, increases in cytosolic [Ca2+] often resulted, after a lag, in sparks that propagated transversally. An increase in [Mg2+] caused a fall of spark frequency, but with striking species differences. In the rat, but not the frog, sparks were observed at 4–40 mM [Mg2+]. Reducing [Mg2+] below 2 mM, which should enable the RyR channel's activation (CICR) site to bind Ca2+, caused progressive increase in spark frequency in the frog, but had no effect in the rat. Spark propagation and enhancement by sub-mM Mg2+ are hallmarks of CICR. Their absence in the rat suggests that CICR requires RyR3 para-junctional clusters, present only in the frog. The observed frequency of sparks corresponds to a channel open probability of 10−7 in the frog or 10−8 in the rat. Together with the failure of photorelease to induce activation directly, this indicates a basal inhibition of channels in situ. It is proposed that relief of this inhibition could be the mechanism by which increased SR load increases spark frequency.
Connections Between Connexins, Calcium, and Cataracts in the Lens
Authors: Gao Junyuan , Sun Xiurong , Martinez-Wittinghan Francisco J. , Gong Xiaohua , White Thomas W. , Mathias Richard T.
Published: September 2004

There is a good deal of evidence that the lens generates an internal micro circulatory system, which brings metabolites, like glucose, and antioxidants, like ascorbate, into the lens along the extracellular spaces between cells. Calcium also ought to be carried into the lens by this system. If so, the only path for Ca2+ to get out of the lens is to move down its electrochemical gradient into fiber cells, and then move by electrodiffusion from cell to cell through gap junctions to surface cells, where Ca-ATPase activity and Na/Ca exchange can transport it back into the aqueous or vitreous humors. The purpose of the present study was to test this calcium circulation hypothesis by studying calcium homeostasis in connexin (Cx46) knockout and (Cx46 for Cx50) knockin mouse lenses, which have different degrees of gap junction coupling. To measure intracellular calcium, FURA2 was injected into fiber cells, and the gradient in calcium concentration from center to surface was mapped in each type of lens. In wild-type lenses the coupling conductance of the mature fibers was ∼0.5 S/cm2 of cell to cell contact, and the best fit to the calcium concentration data varied from 700 nM in the center to 300 nM at the surface. In the knockin lenses, the coupling conductance was ∼1.0 S/cm2 and calcium varied from ∼500 nM at the center to 300 nM at the surface. Thus, when the coupling conductance doubled, the concentration gradient halved, as predicted by the model. In knockout lenses, the coupling conductance was zero, hence the efflux path was knocked out and calcium accumulated to ∼2 μM in central fibers. Knockout lenses also had a dense central cataract that extended from the center to about half the radius. Others have previously shown that this cataract involves activation of a calcium-dependent protease, Lp82. We can now expand on this finding to provide a hypothesis on each step that leads to cataract formation: knockout of Cx46 causes loss of coupling of mature fiber cells; the efflux path for calcium is therefore blocked; calcium accumulates in the central cells; at concentrations above ∼1 μM (from the center to about half way out of a 3-wk-old lens) Lp82 is activated; Lp82 cleaves cytoplasmic proteins (crystallins) in central cells; and the cleaved proteins aggregate and scatter light.
An efficient Monte Carlo approach to assessing statistical significance in genomic studies
Authors: Lin D. Y.
Published: September 2004

Motivation: Multiple hypothesis testing is a common problem in genome research, particularly in microarray experiments and genomewide association studies. Failure to account for the effects of multiple comparisons would result in an abundance of false positive results. The Bonferroni correction and Holm's step-down procedure are overly conservative, whereas the permutation test is time-consuming and is restricted to simple problems.

Results: We developed an efficient Monte Carlo approach to approximating the joint distribution of the test statistics along the genome. We then used the Monte Carlo distribution to evaluate the commonly used criteria for error control, such as familywise error rates and positive false discovery rates. This approach is applicable to any data structures and test statistics. Applications to simulated and real data demonstrate that the proposed approach provides accurate error control, and can be substantially more powerful than the Bonferroni and Holm methods, especially when the test statistics are highly correlated.

Contact:  lin@bios.unc.edu
A linear viscoelastic creep‐contact model of a flat fractal surface: Kelvin‐Voigt medium
Authors: Abuzeid Osama M.
Published: September 2004

The objective of this paper is to construct a continuous model for the viscoelastic contact of a nominal flat punch and a smooth surface of a rigid half‐space. The considered model aims at studying the normal approach as a function of the applied load. The proposed model assumes the punch surface material to behave according to Kelvin‐Voigt viscoelastic material. The punch surface, which is known to be fractal in nature, is modelled in this work using a deterministic Cantor structure. An asymptotic power law, deduced using iterative relations, is used to express the punch surface approach as a function of the remote force when the approach of the punch surface and the half space is in the order of the size of the surface roughness. The results obtained using this model, which admits closed form solution, are displayed graphically for selected values of the system parameters; the fractal surface roughness and various material properties. The obtained results showed good agreement with published experimental results.
UNI Europa Graphical's approach to the co‐ordination of national level collective bargaining within a European context
Authors: Gennard John
Published: September 2004

This paper outlines the purpose and the economic theory underpinning the Uni‐Europa Graphical co‐ordination of collective bargaining within a European context policy. It then analyses the development of the policy in terms of its scope, its institutions and its information networks. It discusses the statistical series and quantification problems involved in attempting to assess the extent to which the policy's guidelines are being achieved. The majority of UEG affiliates, however, are experiencing difficulties in gaining bargained wage increases at the national level equal to the sum of inflation increases plus average national productivity increases. Finally, it assesses the future prospects for the policy.
Management and the management of information and library services 2000
Authors: Layzell Ward Patricia
Published: September 2004

Focuses on the year 2000, reviewing the periodical literature of information and library services management, and of the relevant literature from the field of management in general. Notes the themes of major conferences in the field of information and library services management, and of reference tools for library managers.
Mentoring and coaching as part of a human resource development strategy: an example at Coca‐Cola Foods
Authors: Veale David J.
Published: September 2004

Describes Coca‐Cola Foods’ mentoring and coaching programmes. Presents directions for future research and practice based on Coca‐Cola Foods’ experience.
Award‐winning shape acquisition speeds up prototype production
Authors: Alcock Ian
Published: September 2004

A consortium of UK companies has developed a high speed, high accuracy 3D shape acquisition system called Photoform that can dramatically speed up prototype production in a whole range of industries. The system uses a fibre optic laser delivery system to project interference fringes on to a 3D surface, which is then viewed by a camera and analysed to give 12‐micron measurement accuracy over the surface.