bluuebunny/crossref_metadata_2025 huggingface dataset:
Presence and interaction of inflammatory cells in the spleen of Atlantic cod, Gadus morhua L., infected with Francisella noatunensis
Authors: Gjessing M C , Inami M , Weli S C , Ellingsen T , Falk K , Koppang E O , Kvellestad A
Published: August 2011

Serious infectious diseases, accompanied by macrophage‐dominated chronic inflammation, are common in farmed Atlantic cod. To increase knowledge relating to morphological aspects of such inflammatory responses, cod were challenged with Francisella noatunensis, an important bacterial pathogen of this fish species. Tissue and cell dynamics in the spleen were examined sequentially over 60 days. Small clusters of mainly macrophage‐like cells (MLCs) staining for non‐specific esterase and acid phosphatase developed with time. These foci were transiently infiltrated by pleomorphic proliferating cells of unknown nature and by granulocyte‐like cells (GCLCs) staining for peroxidase and lysozyme. The latter cell type, which appeared to be resident in the red pulp of control fish, migrated into the inflammatory foci of infected fish. Cells expressing genes encoding IFN‐γ and IL‐8 increased in number during the study period. Bacteria were detected only in the MLCs and their number increased despite the extensive inflammation. Our results demonstrate an intimate spatial relationship in inflammatory foci between at least three cell types. The presence of GCLCs, together with MLCs, suggests pyogranulomatous inflammation as a more appropriate descriptive term than granulomatous inflammation.
Non‐invasive magnetic stimulation of the human cerebellum facilitates cortico‐bulbar projections in the swallowing motor system
Authors: Jayasekeran V. , Rothwell J. , Hamdy S.
Published: August 2011

Background  Animal and human brain imaging studies suggest that the cerebellum plays an important role in the control of swallowing. In this study, we probed the interaction between cerebellar and pharyngeal motor cortical activity with transcranial magnetic stimulation (TMS) to determine if the cerebellum can modulate cortical swallowing motor circuitry.

Methods  Healthy volunteers (n = 16, eight men, mean age = 32, range 19–57 years) underwent TMS measurements of pharyngeal electromyography (EMG) recorded from a swallowed intraluminal catheter to assess cortical and cerebellar excitability. Subjects then underwent a paired pulse paradigm, where active or sham TMS conditioning pulses over the cerebellum and control sites were followed by suprathreshold TMS over the cortical pharyngeal area. Paired pulses were delivered at varying inter‐stimulus intervals (ISIs) with the cortical response amplitudes being assessed.

Key Results  Stimulation of the cerebellum over its midline or hemispheres evoked distinct pharyngeal EMG responses. There was no difference in EMG amplitudes following cerebellar hemispheric or midline stimulation (mean 55.5 ± 6.9 vs 42.8 ± 5.9 μV, P = 0.08). In contrast, after cerebellar preconditioning, the cortically evoked responses underwent maximal facilitation at ISIs of 50–200 ms (P < 0.05), an effect not seen with sham or trigeminal nerve preconditioning.

Conclusions & Inferences  Posterior fossa stimulation excites the cerebellum and evokes direct motor responses within the pharynx. When conditioned with TMS, the cerebellum strongly facilitates the cortical swallowing motor pathways. This finding suggests that the cerebellum exerts a modulatory effect on human swallowing and raises the possibility that excitatory neurostimulation of the cerebellum may be therapeutically useful in promoting recovery of dysphagia after neural damage.
The electrifying stomach
Authors: Koch K. L.
Published: August 2011

The stomach is electrified and subject to eurhythmic and dysrhythmic electrical events – much like the heart. The normal human slow wave ranges from 2.5 to 3.75 cycles per min (cpm), tachygastrias range from 3.75 cpm to 10.0 cpm and bradygastrias from .5 to 2.5 cpm, the gastric dysrhythmias of men and women. In this issue of Neurogastroenterology & Motility, O’Grady, et al. describe the gastric dysrhythmias of pigs in electrocardiology terms. Printed circuit boards (PCB) with multi‐electrode arrays (160–192 electrodes) were attached to the stomach serosa. Gastric dysrhythmias occurred in eight of the 16 anesthetized pigs and were analysed by manually and by computer. The patterns of dysrhythmias were reminiscent of cardiac dysrhythmias: conduction blocks, ectopic foci, re‐entrant wave fronts, premature and aberrant slow waves and regular and irregular tachygastrias. The authors suggest gastric dysrhythmias recorded in pigs may be relevant to human gastric dysrhythmias and electricity‐based therapies. The categories of porcine gastric dysrhythmias may help to understand the spectrum of gastric dysrhythmias of men and women recorded over the past 25 years. Analogies between gastric and cardiac neuromuscular disorders are explored because Neurogastroenterology is evolving as a clinical and therapeutic field utilizing knowledge of gastric rhythmicity and electro‐contractile events. Interstitial cells of Cajal are the pacemaker cells of the stomach and loss of cells or faulty circuitry appear to be key pathways to gastric dysrhythmias. Gastric electrophysiology (EP) labs, human and animal, are needed to test hypotheses and advance understanding of human gastric dysrhythmias and upper GI symptoms.
Limited plasticity of low temperature tolerance in an Australian cantharid beetle Chauliognathus lugubris
Authors: ANDREW NIGEL R. , HART ROBERT A. , TERBLANCHE JOHN S.
Published: August 2011

Spatial and/or taxonomic bias in thermal tolerance and plasticity data can severely impact projections of climate change responses and limit the understanding of the evolution of thermal performance curves. Thus, further data from under‐represented groups and geographical locations are important for synthesizing and predicting the physiological responses of insects to climate variability. For example, the magnitude of rapid cold‐hardening (RCH) and seasonal acclimatization of low temperature tolerance are typically poorly documented for nondipteran species from the southern Hemisphere. Moreover, few studies assess RCH responses under different acclimation regimes. To address this paucity of data, the low temperature survival, RCH and acclimation ability of Chauliognathus lugubris (F.) are assessed from an adult aggregation collected in Armidale, New South Wales, Australia. Beetles are acclimated to either 27 or 20 °C for 1 week and then tested for their ability to survive cold shock or rapidly cold‐harden. There is no effect of acclimation on low temperature survival (mean survival range at −5.4 °C for 2 h: 4–52% in 27 and 20 °C acclimation groups). In addition, beetles show no significant improvement in survival after acute thermal pretreatments. In conclusion, these data suggest a generally poor acclimation potential of low temperature survival and no RCH responses in adult Australian cantharid beetles, which is accordance with what might be expected given the microclimate experienced, their ability for behavioural regulation and the life history of the species.
Do reproductive activities compromise immunological competence as measured by phenoloxidase activity? Field and experimental manipulation in females of two damselfly species
Authors: CÓRDOBA‐AGUILAR ALEX , RUIZ‐SILVA DANIELA , MUNGUÍA‐STEYER ROBERTO , LANZ‐MENDOZA HUMBERTO
Published: August 2011

Recent studies of female insects indicate that reproductive activities, such as mating and oviposition, can impair immune ability. Using the two tropical damselfly species Argia anceps Garrison and Hetaerina americana (Fabricius), egg production and phenoloxidase (PO) activity, a key enzyme in insect immunity, are measured in mating, ovipositing and perching females in December and March. Perching females of both species have fewer eggs compared with mating and ovipositing females, which suggests that perching females are not engaged in reproduction. There is seasonal variation in egg number for the three categories in H. americana but not in A. anceps, which can be interpreted in terms of adaptive changes in egg production depending on female–male interactions in the former species but not in the latter species. There is no difference in PO activity among mating, ovipositing or perching females within either species, although measurements in December and March indicate distinct seasonal changes. Juvenile Hormone (JH) is known to reduce the effectiveness of the immune system by favouring the use of resources for reproduction. A possible role for JH is examined in H. americana, using the JH analogue methoprene to manipulate hormone activity, revealing that PO activity is reduced in methoprene‐treated H. americana females. Thus, although the results of the present study are indicative of possible hormone‐driven changes in PO, there is not necessarily a down‐regulation of immune function (as determined by PO activity) during mating or oviposition. The results complement some recent studies countering the idea that reproductive activities reduce the immune ability in insects.
Tn5 transposon mutagenesis in Acidovorax citrulli for identification of genes required for pathogenicity on cucumber
Authors: Liu J. , Luo S. Z. , Zhang Q. , Wang Q. H. , Chen J. F. , Guo A. G. , Shan W. X.
Published: August 2011

An Acidovorax citrulli–cucumber pathosystem was established through which A. citrulli mutants with altered pathogenicity, generated by transposon mutagenesis, were identified on cucumber cotyledons. The A. citrulli group I strain FC440 was shown to grow faster in cucumber leaf tissues than a group II strain and was used for Tn5 transposon mutagenesis. A total of 2100 Tn5 insertional mutants were generated, and analysis of the mutant library showed that the transposon insertions were single, independent and stable. A conserved non‐flagellar type III secretion system (NF‐T3SS) ATPase gene hrcN was identified and confirmed to be essential for pathogenicity and functionality of NF‐T3SS in A. citrulli. Comparative sequence analysis of the HrcN protein and its homologues in other representative bacterial plant pathogens revealed that the NF‐T3SS of A. citrulli is close to that of Ralstonia solanacearum and Xanthomonas campestris, but distant from that of Pseudomonas syringae and Erwinia amylovora. The generated Tn5 insertional mutant collection is valuable for identification of genes required for A. citrulli pathogenesis, and the established A. citrulli–cucumber pathosystem will facilitate an improved understanding of A. citrulli biology and pathology.
Resistance to Pseudomonas syringae in a collection of pea germplasm under field and controlled conditions
Authors: Martín‐Sanz A. , Pérez de la Vega M. , Caminero C.
Published: August 2011

A total of 242 Pisum accessions were screened for resistance to Pseudomonas syringae pv. pisi under controlled conditions. Resistance was found to all races, including race 6 and the recently described race 8. Fifty‐eight accessions were further tested for resistance to P. syringae pv. syringae under controlled conditions, with some highly resistant accessions identified. Finally, a set of 41 accessions were evaluated for resistance to P. syringae pv. pisi and pv. syringae under spring‐ and winter‐sowing field conditions. R2, R3 and R4 race‐specific resistance genes to P. syringae pv. pisi protected pea plants in the field. Resistance sources to race 6 identified under controlled conditions were ineffective in the field. Frost effects were also evaluated in relation to disease response. Results strongly suggest that frost tolerance is effective in lowering the disease effects caused by P. syringae pv. pisi and pv. syringae under frost‐stress conditions, even in the absence of disease resistance genes, although the highest degree of this protection is reached when frost tolerance and disease‐resistance genes are combined in the same genetic background.
Comparative spatial analysis of the sooty blotch/flyspeck disease complex, bull’s eye and bitter rots of apples
Authors: Spolti P. , Valdebenito‐Sanhueza R. M. , Laranjeira F. F. , Del Ponte E. M.
Published: August 2011

The incidence of sooty blotch/flyspeck (SBFS) and bitter and bull’s eye rots were assessed in a Fuji apple orchard during two seasons. Using a regular sampling design, 252 trees were selected and 20 fruits per tree were sampled at harvest and scored for disease incidence. For bitter and bull’s eye rots, additional assessments were made on all symptomless fruit after a 30‐day period of storage. Randomness in the spatial pattern was assessed using beta‐binomial analysis of incidence data for three sampling scales (one, three or six adjacent trees as sampling units) and using Spatial Analysis by Distance Indices (sadie) for disease counts for the 3‐tree sampling scale. sadie was also used for testing spatial associations between a pair of diseases, between years for the same disease or between rotted and latently infected fruit. Using a toroidal‐shifts procedure, 360 maps of disease counts were created based on the observed data, which were further analysed using sadie. Most datasets showed an aggregated spatial pattern, which was more consistent for the two fruit rots than SBFS, which showed distinct patterns depending on the year or method of analysis. The two fruit rots were spatially associated in most situations but SBFS and bull’s eye rot were dissociated in one season. Results from virtual orchards showed that the patterns observed in the original maps may accurately represent those in similar apple‐growing areas. Hypotheses regarding aspects of ecology and epidemiology of pathogens studied and potential efficacy of control measures in the region are discussed.
mRNA from selected genes is useful for specific detection and quantification of viable Xanthomonas citri subsp. citri
Authors: Golmohammadi M. , Llop P. , Scuderi G. , Gell I. , Graham J. H. , Cubero J.
Published: August 2011

The purpose of this study was to assess the stability of mRNA and rRNA for evaluation of viability for Xanthomonas citri subsp. citri (Xcc). Total RNA from Xcc suspensions subjected to different stress treatments (high temperature or chemical treatment with sodium orthophenylphenate at different concentrations) was extracted at different time periods post‐treatment (0, 3, 24 and 48 h) and analysed by quantitative real‐time reverse transcription PCR (Q‐RT‐PCR). Primers were designed from selected fragments of rRNA and mRNA from genes involved in bacterial fitness, virulence or general metabolic mechanisms (gumD, rpfB, avrBs2 and gyrB). After stress treatment, only a 445‐bp fragment from the gumD mRNA was detected in live Xcc cells specifically, whereas other RNA fragments, as well as DNA targets, were detected in both viable and nonviable cells. Statistical analyses demonstrated that the amount of some transcripts from genes involved in xanthan synthesis, pathogenicity factor regulation and DNA processing was significantly reduced after lethal treatments. The amplification of the 445‐bp product from gumD mRNA was demonstrated to be useful for the detection of viable Xcc; the product was detected specifically from viable bacteria on leaf and citrus fruit surfaces and in citrus canker lesions. Instability of long RNA fragments can be used as a practical tool for the study of survival of citrus canker bacteria or for diagnostic purposes when the presence of viable bacteria needs to be confirmed.
Patient delay determinants for patients with suspected tuberculosis in Yogyakarta province, Indonesia
Authors: Lock Willem A. , Ahmad Riris A. , Ruiter Robert A. C. , van der Werf Marieke J. , Bos Arjan E. R. , Mahendradhata Yodi , de Vlas Sake J.
Published: August 2011

Objectives  Indonesia has a high incidence of tuberculosis (TB), despite the successful introduction of the directly observed treatment short‐course strategy (DOTS strategy). DOTS depends on passive case finding. It is therefore important to identify determinants of patient delay and reasons for visiting a DOTS healthcare provider when seeking care. The aim of this study was to assess these determinants in TB suspects (coughing for at least 2 weeks).

Methods  Cross‐sectional data were gathered with a structured questionnaire in which psychosocial determinants were based on an extended version of the theory of planned behaviour (TPB). The study was conducted in five governmental lung clinics of Yogyakarta province. In total, 194 TB suspects that registered at the lung clinics were interviewed.

Results  The median patient delay was 14 days (range 0–145). Ordinal regression analyses showed that visiting a private healthcare provider when first seeking health care, reporting travel distance/travel time as reason for choosing a certain healthcare provider when first seeking health care, discussing the symptoms with family and a reported short travel time, but no factors of TPB, were significantly associated with a shorter patient delay. An important factor negatively associated with visiting a DOTS clinic was the reported travel time.

Conclusion  Accessibility of the healthcare provider was the main determinant of patient delay, but the role of psychosocial factors cannot be fully excluded. Urban and suburban areas have relatively good access to (private) health care, hence the short delay. Thus, future studies should be focussed on extending the DOTS strategy to the private sector.
Prioritization based on neutral genetic diversity may fail to conserve important characteristics in cattle breeds
Authors: Hall S.J.G. , Lenstra J.A. , Deeming D.C. ,   The European Cattle Genetic Diversity Consortium
Published: August 2011

Conservation of the intraspecific genetic diversity of livestock species requires protocols that assess between‐breed genetic variability and also take into account differences among individuals within breeds. Here, we focus on variation between breeds. Conservation of neutral genetic variation has been seen as promoting, through linkage processes, the retention of useful and potentially useful variation. Using public information on beef cattle breeds, with a total of 165 data sets each relating to a breed comparison of a performance variable, we have tested this paradigm by calculating the correlations between pairwise breed differences in performance and pairwise genetic distances deduced from biochemical and immunological polymorphisms, microsatellites and single‐nucleotide polymorphisms. As already observed in floral and faunal biodiversity, significant positive correlations (n = 54) were found, but many correlations were non‐significant (n = 100) or significantly negative (n = 11). This implies that maximizing conserved neutral genetic variation with current techniques may conserve breed‐level genetic variation in some traits but not in others and supports the view that genetic distance measurements based on neutral genetic variation are not sufficient as a determinant of conservation priority among breeds.
Antifungal activities of Astragalus verus Olivier. against Trichophyton verrucosum on in vitro and in vivo guinea pig model of dermatophytosis
Authors: Mikaeili Ali , Modaresi Masoud , Karimi Isaac , Ghavimi Hamed , Fathi Mazyar , Jalilian Nastaran
Published: August 2011

Astragalus verus Olivier, Fabaceae has been used against ringworm in Kurdish ethnomedicine throughout millennia. The objective of this study was to evaluate the effects of A. verus extracts against Trichophyton verrucosum on in vitro and in vivo guinea pig model of dermatophytosis. The skin of albino guinea pigs was infected with T. verrucosum (1.0 × 107 conidia) and animals were divided into five groups (n = 5 for each): negative control (NC), received a vehicle; positive control (PC), received topical terbinafine 1.0% and three other groups: AE10%, AE20% and AE40% which received topical 10%, 20% and 40% aqueous extract of A. verus, respectively. Evaluation of clinical efficacy was performed 72 h after completion of a 7‐day treatment regimen. Higher significant antifungal activities were observed in aqueous extract in the concentration 320 mg ml−1 compared with acetone and methanol extracts. The aqueous extract showed minimum inhibitory concentration at 160 mg ml−1. Lower clinical scores indicate improved efficacy compared with NC. The lesion scores significantly declined in AE20%, AE40% and PC groups in comparison with NC group. The lesion scores in AE10% and AE20% groups were significantly higher than that of PC group. The AE10% group (18.3%) and AE20% group (39.43%) and AE40% group (66.19%) showed clinical efficacies compared with PC group (76.05%). In conclusion, aqueous extract showed promising antidermatophytic activity.
Trappings of technology: casting palliative care nursing as legal relations
Authors: Larsen Ann‐Claire
Published: August 2011

LARSEN A‐C. Nursing Inquiry 2012; 19: 334–344  Trappings of technology: casting palliative care nursing as legal relations

Community palliative care nurses in Perth have joined the throng of healthcare workers relying on personal digital assistants (PDAs) to store, access and send client information in ‘real time’. This paper is guided by Heidegger’s approach to technologies and Habermas’ insights into the role of law in administering social welfare programs to reveal how new ethical and legal understandings regarding patient information add to nursing’s professional responsibilities. This qualitative research interprets data from interviews with twenty community palliative care nurses about clients’ legal rights to informational privacy and confidentiality. It explores nurses’ views of their nursing responsibilities regarding clients’ legal rights, liability issues, bureaucratic monitoring and enforcement procedures. It concludes that nurses and clients are construed as legal subjects entrenched in legal relations that have magnified since these nurses began using PDAs in 2005/2006.
Disturbed vibrotactile sense in finger pulps in patients with Type 1 diabetes—correlations with glycaemic level, clinical examination and electrophysiology
Authors: Dahlin L. B. , Granberg V. , Rolandsson O. , Rosén I. , Dahlin E. , Sundkvist G.
Published: August 2011

Diabet. Med. 28, 1045–1052 (2011)

Aims  In a cohort of men and women with Type 1 diabetes, prospectively followed for > 20 years, vibrotactile sense in fingers was investigated and related to neurophysiological tests, glycaemic level and clinical score.

Methods  Out of 58 patients, diagnosed at the age of 15–25 years and recruited 1984–1985, 32 patients (13 women, median age 52 years, range 44–75 years; 19 men, median age 52 years, range 39–69 years; median duration 33.5 years, range 21–52 years) accepted follow‐up in 2006. Vibration thresholds were measured in finger pulps of index and little fingers bilaterally at seven frequencies and related to results of touch (monofilaments), tactile discrimination (two‐point discrimination test), electrophysiology (median nerve function), glycaemic level (HbA1c levels since 1984–1985) and a clinical score.

Results  Vibrotactile sense was reduced in finger pulps, mainly in men, compared with an age‐ and gender‐matched healthy control group with normal HbA1c. Vibration thresholds were increased, particularly at 250 and 500 Hz, in both index and little finger pulps. Touch and tactile discrimination correlated with vibration thresholds, but not with each other or with electrophysiology. HbA1c levels (at follow‐up or mean values from five follow‐ups since recruitment) did not correlate with any nerve function variables. Clinical scores correlated with vibrotactile sense, particularly at higher frequencies (> 125 Hz), but not with total Z‐scores of electrophysiology. Duration of disease did not correlate with any variables.

Conclusions  Examination of vibration thresholds in index and little finger pulps may be valuable to detect neuropathy, where thresholds correlate with symptoms and tests.
Information content of earnings announcements in the New Zealand equity market, a longitudinal analysis
Authors: Truong Cameron
Published: August 2011

We compute abnormal return variance and abnormal trading volume in the 3‐day window surrounding earnings announcements to examine the information content of earnings announcements in the New Zealand equity market over the past 16 years. We find that the information content of earnings announcements has increased significantly over time, and this finding holds true for both interim and preliminary earnings announcements. We find evidence that earnings announcements with June year‐ends exhibit a higher level of information content and experience a more pronounced rising trend as compared to earnings announcements with non‐June year‐ends. Several firm characteristics appear to relate to the level of the information content of earnings announcements as well as to compound the trend over time. We document an important finding that the information content of earnings announcements increases remarkably in the period after the adoption of the International Financial Reporting Standards (IFRS).
Molecular, phylogenetic and comparative genomic analysis of the cytokinin oxidase/dehydrogenase gene family in the Poaceae
Authors: Mameaux Sabine , Cockram James , Thiel Thomas , Steuernagel Burkhard , Stein Nils , Taudien Stefan , Jack Peter , Werner Peter , Gray John C. , Greenland Andy J. , Powell Wayne
Published: August 2011

The genomes of cereals such as wheat (Triticum aestivum) and barley (Hordeum vulgare) are large and therefore problematic for the map‐based cloning of agronomicaly important traits. However, comparative approaches within the Poaceae permit transfer of molecular knowledge between species, despite their divergence from a common ancestor sixty million years ago. The finding that null variants of the rice gene cytokinin oxidase/dehydrogenase 2 (OsCKX2) result in large yield increases provides an opportunity to explore whether similar gains could be achieved in other Poaceae members. Here, phylogenetic, molecular and comparative analyses of CKX families in the sequenced grass species rice, brachypodium, sorghum, maize and foxtail millet, as well as members identified from the transcriptomes/genomes of wheat and barley, are presented. Phylogenetic analyses define four Poaceae CKX clades. Comparative analyses showed that CKX phylogenetic groupings can largely be explained by a combination of local gene duplication, and the whole‐genome duplication event that predates their speciation. Full‐length OsCKX2 homologues in barley (HvCKX2.1, HvCKX2.2) and wheat (TaCKX2.3, TaCKX2.4, TaCKX2.5) are characterized, with comparative analysis at the DNA, protein and genetic/physical map levels suggesting that true CKX2 orthologs have been identified. Furthermore, our analysis shows CKX2 genes in barley and wheat have undergone a Triticeae‐specific gene‐duplication event. Finally, by identifying ten of the eleven CKX genes predicted to be present in barley by comparative analyses, we show that next‐generation sequencing approaches can efficiently determine the gene space of large‐genome crops. Together, this work provides the foundation for future functional investigation of CKX family members within the Poaceae.
Variables influencing the return on investment in management training programs: a utility analysis of 10 Swiss cases
Authors: Chochard Yves , Davoine Eric
Published: August 2011

In this article, we present the utility analysis approach as an alternative and promising approach to measure the return on investment in managerial training programs. This approach, linking economic value with competencies developed by trainees, enables researchers and decision‐makers to compare the return on investment from different programs in different organizations. Despite the potential contribution of utility analysis, few studies have adopted this approach to evaluate return on investment. This article demonstrates the value of utility analysis through a brief review of former studies and a report of our own evaluation results based on data collected in 10 cases from 158 managers. The article focuses on three main variables influencing return on investment as identified in former studies: the duration and thematic focus of training programs, the job class of the trainees and the research design.
Using collaborative action learning projects to increase the impact of management development
Authors: Lysø Ingunn Hybertsen , Mjøen Kristian , Levin Morten
Published: August 2011

This article aims to contribute to the field of human resource development by exploring the conditions that influence the organizational impact of action learning projects. Many organizations use such projects as an integral part of their management development programs. Past research on action learning projects has shown how balancing action and learning improves the organizational impact of management development, but we argue that the concern with such a balance is not enough. We argue that certain organizational conditions are likely to mediate this balance. Based on empirical material from a case study of one off‐site management development program, we identify three organizational conditions that seem to enhance organizational impact: clear reasons for enrolling managers on a development program, support from the manager's local superior throughout the process of the action learning project and local participation in the project work on the part of the manager's employer. These findings have practical implications for providers of management development programs as well as for organizations exploring ways of enhancing the impact of their investment in management learning and development. In terms of theory, the lack of organizational impact of action learning projects can be seen as part of the wider ‘transfer problem’ in training and development, and the results of the present study are consistent with the literature, which shows factors in the work environment to be important in facilitating or preventing transfer.
The Effectiveness of English Secondary Schools for Pupils of Different Ability Levels*
Authors: Dearden Lorraine , Micklewright John , Vignoles Anna
Published: August 2011

‘League table’ information on school effectiveness in England generally relies either on a comparison of the average outcomes of pupils by school (for example, mean exam scores) or on estimates of the average value added by each school. These approaches assume that the information parents and policymakers need most to judge school effectiveness is the average achievement level or gain in a particular school. Yet schools can be differentially effective for children with differing levels of prior attainment. We present evidence on the extent of differential effectiveness in English secondary schools and find that even the most conservative estimate suggests that around one‐quarter of schools in England are differentially effective for students of differing prior ability levels. This affects an even larger proportion of children, as larger schools are more likely to be differentially effective.
Can School League Tables Help Parents Choose Schools?*
Authors: Allen Rebecca , Burgess Simon
Published: August 2011

Information on schools' performance is central to the school choice process in England. This paper evaluates school performance tables against criteria of functionality, relevance and comprehensibility. We estimate a model to judge functionality by setting up the following question: ‘In which feasible school will my child achieve the highest exam score?’. We show that neither of the current leading performance measures scores very well. We propose an alternative measure which performs better on relevance and comprehensibility and not significantly worse on functionality. We demonstrate how the measure could be best delivered to parents. We also describe the trade‐offs between the criteria of functionality and relevance and between comprehensibility and relevance.
Measuring School Value Added with Administrative Data: The Problem of Missing Variables*
Authors: Dearden Lorraine , Miranda Alfonso , Rabe‐Hesketh Sophia
Published: August 2011

The UK Department for Education (DfE) calculates contextual value added (CVA) measures of school performance using administrative data that contain only a limited set of explanatory variables. Differences in schools' intakes regarding characteristics such as mother's education are not accounted for due to the lack of background information in the data. In this paper, we use linked survey and administrative data to assess the potential biases that missing control variables cause in the calculation of CVA measures of school performance. We find that ignoring the effect of mother's education leads the DfE to erroneously overpenalise low‐achieving schools that have a greater proportion of mothers with low qualifications and to over‐reward high‐achieving schools that have a greater proportion of mothers with higher qualifications. This suggests that collecting a rich set of controls in administrative records is necessary for producing reliable CVA measures of school performance.
Assessing Educational Effectiveness: Policy Implications from Diverse Areas of Research*
Authors: Marsh Herbert W. , Nagengast Benjamin , Fletcher John , Televantou Ioulia
Published: August 2011

In England, school league tables – based on student scores on standardised tests – are used extensively by policymakers and parents as one of the key measures of secondary school effectiveness. Here, we briefly review the English contextual value added (E‐CVA) model used to construct league tables of school effectiveness and juxtapose it with studies that focus on teacher effectiveness, other criteria of educational effectiveness and effectiveness at the university level. Methodologically, we consider the fragility of causal inferences based on psychometric and econometric value added models, and new multilevel models that take into account measurement and sampling error. Value added models largely ignore measurement error which systematically biases the outcomes, but both measurement and sampling error can be incorporated into doubly‐latent models that integrate multilevel and latent variable approaches. The E‐CVA model focuses on school effects and ignores teacher effects. However, research on both secondary schools and universities shows that there is little variance at the school or university level, but much more at the teacher level. E‐CVA models consider test scores as the only indicator of effectiveness; there is little emphasis on other indicators of effectiveness, tests of the construct validity of test scores as a measure of effectiveness in relation to other indicators, or formative evaluations to improve effectiveness. Research on university students' ratings of teachers incorporates a broader perspective to construct validation: multidimensional factor structure, reliability/stability, relations with multiple criteria of effective teaching, and interventions to improve teaching. Both areas of research could learn from the other, and many strategies from the higher‐education literature could be incorporated into the literature on educational effectiveness at the primary‐ and secondary‐school levels.
Recent Developments in the Identification and Estimation of Production Functions of Skills*
Authors: Cunha Flávio
Published: August 2011

This paper summarises the literature on the estimation of production functions governing the process of skill formation. This literature focuses on attacking three problems. The first is the endogeneity of measures of investments. The second is the measurement error in skills and investments that are widely used in the literature. Endogeneity and measurement error produce, in general, inconsistent estimates. The third problem is the lack of a metric for tests designed to measure skills. The fact that scores have no cardinal meaning implies that the coefficients of the production function have no economic meaning. We show that anchoring test scores on outcomes that have a natural metric produces estimates that are economically interpretable.
Previous overt hepatic encephalopathy rather than minimal hepatic encephalopathy impairs health‐related quality of life in cirrhotic patients
Authors: Moscucci Federica , Nardelli Silvia , Pentassuglio Ilaria , Pasquale Chiara , Ridola Lorenzo , Merli Manuela , Riggio Oliviero
Published: August 2011

Background

It has been observed that overt hepatic encephalopathy (HE) is accompanied by a persistent cognitive defect, suggesting that HE may not be fully reversible. The health‐related quality‐of‐life (HRQoL) has been shown to be impaired by cirrhosis, and, according to some reports, influenced by minimal HE. Little is known about the effect of previous HE on HRQoL.

Aim

To investigate the relative impact of previous HE and minimal HE on HRQoL in a group of consecutively hospitalized cirrhotic patients.

Patients/Methods

Seventy five consecutive cirrhotic patients were evaluated using the Psychometric HE Score (PHES) and simplified Psychometric HE Score (SPHES) to detect the presence of minimal HE and using SF‐36 to assess the HRQoL, both corrected for age and education. Eighteen of them had previous bouts of overt HE.

Results

Minimal HE was significantly more frequent in patients with previous HE than in those without (p < 0.001), independently on the method used for the diagnosis (PHES or SPHES). A deeper impairment in several domains of SF‐36 was observed in patients with previous bouts of overt HE, in those with ascites, as well as in those with decompensated cirrhosis. At multivariate analysis, ascites, MELD score and previous HE were independently related to the mental‐component‐summary (MCS) of SF‐36, whereas ascites was the only variable independently associated with the physical‐component‐summary (PCS) of SF‐36. Minimal HE (independently on the method used for its diagnosis) impaired only one domain of SF‐36.

Conclusions

These data suggest that previous bouts of HE, despite their complete clinical resolution, play an independent role in producing a persistent impairment in HRQoL of cirrhotics.
A Method for Control of an Implantable Rotary Blood Pump for Heart Failure Patients Using Noninvasive Measurements
Authors: Lim Einly , Alomari Abdul‐Hakeem H. , Savkin Andrey V. , Dokos Socrates , Fraser John F. , Timms Daniel L. , Mason David G. , Lovell Nigel H.
Published: August 2011

We propose a deadbeat controller for the control of pulsatile pump flow (Qp) in an implantable rotary blood pump (IRBP). Noninvasive measurements of pump speed and current are used as inputs to a dynamical model of Qp estimation, previously developed and verified in our laboratory. The controller was tested using a lumped parameter model of the cardiovascular system (CVS), in combination with the stable dynamical models of Qp and differential pressure (head) estimation for the IRBP. The control algorithm was tested with both constant and sinusoidal reference Qp as input to the CVS model. Results showed that the controller was able to track the reference input with minimal error in the presence of model uncertainty. Furthermore, Qp was shown to settle to the desired reference value within a finite number of sampling periods. Our results also indicated that counterpulsation yields the minimum left ventricular stroke work, left ventricular end diastolic volume, and aortic pulse pressure, without significantly affecting mean cardiac output and aortic pressure.
Evaluation of Hydraulic Radial Forces on the Impeller by the Volute in a Centrifugal Rotary Blood Pump
Authors: Boehning Fiete , Timms Daniel L. , Amaral Felipe , Oliveira Leonardo , Graefe Roland , Hsu Po‐Lin , Schmitz‐Rode Thomas , Steinseifer Ulrich
Published: August 2011

In many state‐of‐the‐art rotary blood pumps for long‐term ventricular assistance, the impeller is suspended within the casing by magnetic or hydrodynamic means. For the design of such suspension systems, profound knowledge of the acting forces on the impeller is crucial. Hydrodynamic bearings running at low clearance gaps can yield increased blood damage and magnetic bearings counteracting high forces consume excessive power. Most current rotary blood pump devices with contactless bearings are centrifugal pumps that incorporate a radial diffuser volute where hydraulic forces on the impeller develop. The yielding radial forces are highly dependent on impeller design, operating point and volute design. There are three basic types of volute design—singular, circular, and double volute. In this study, the hydraulic radial forces on the impeller created by the volute in an investigational centrifugal blood pump are evaluated and discussed with regard to the choice of contactless suspension systems. Each volute type was tested experimentally in a centrifugal pump test setup at various rotational speeds and flow rates. For the pump's design point at 5 L/min and 2500 rpm, the single volute had the lowest radial force (∼0 N), the circular volute yielded the highest force (∼2 N), and the double volute possessed a force of approx. 0.5 N. Results of radial force magnitude and direction were obtained and compared with a previously performed computational fluid dynamics (CFD) study.
Alterations in Red Blood Cell Volume and Hemoglobin Concentration, Viscoelastic Properties, and Mechanical Fragility Caused by Continuous Flow Pumping in Calves
Authors: Yokoyama Naoyuki , Sakota Daisuke , Nagaoka Eiki , Takatani Setsuo
Published: August 2011

In this study, we have analyzed the changes in mean corpuscular volume (MCV), mean corpuscular hemoglobin concentration (MCHC), and the dynamic deformability and mechanical fragility of red blood cells (RBCs) in five male Holstein calves (body weight: 95.6 ± 10.8 kg) whose circulation was partially supported with a novel magnetically levitated extracorporeal centrifugal blood pump MedTech Dispo. One hour after the pumping has started, the MCV increased and the MCHC decreased by 1.064 ± 0.006 and 0.906 ± 0.050 times, respectively, as compared with those of the prepumped blood (P < 0.05). The deformability index L/W, where L and W are the long and short axes of the two‐dimensional RBC images, respectively, sheared by a cyclically reversing shear flow increased indicating that the RBCs pumped for 1 h exhibited more elastic characteristics (P < 0.05). In addition, when the pumped blood cells were sheared for 30 min with a uniform shear stress of 25.38 Pa, the hemolysis level decreased dramatically as compared with the control blood, as more fragile RBCs were destroyed by pumping, leaving behind less fragile RBCs. All these characteristics of the RBCs exposed to continuous flow resemble those of young RBCs having larger MCV, lower MCHC, higher elasticity, and lower fragility. In conclusion, during continuous flow pumping, the RBCs having relatively lower threshold for hemolysis to mechanical shear stress generated by continuous flow blood pump (CFBP) are destroyed first and removed from circulation in the early stage of application of CFBP, thus leaving behind less fragile and stronger RBCs.
Results of Animal Experiments With the Fourth Model of the Undulation Pump Total Artificial Heart
Authors: Abe Yusuke , Isoyama Takashi , Saito Itsuro , Shi Wei , Inoue Yusuke , Ishii Kohei , Nakagawa Hidemoto , Ono Toshiya , Ono Minoru , Imachi Kou
Published: August 2011

Animal experiments using a total artificial heart in a goat are not easy to perform. The fourth model of the undulation pump total artificial heart (UPTAH4), which was designed to perform a long‐term physiological experiment including pulsatile and nonpulsatile TAH operations with a conductance‐ and arterial pressure‐based control method named 1/R control, was implanted in 31 goats weighing 38.5 to 60.4 kg (average of 46.8 kg). The 1/R control is a physiological flow control method of TAH developed with a conductance (1/R: reciprocal of a resistance) parallel circuit model. The survival periods were from 0.1 to 153 days (average of 14.5 days). The causes of termination were postoperative bleeding in eight goats, respiratory failure in five goats, device failure in 14 goats, dissected aneurysm in two goats, and thrombus in one goat. The thrombus case was the longest surviving goat. The respiratory failure tended to occur when the extracorporeal circulation time was prolonged. Autotransfusion was effective for the prolongation of survival time. The left–right balance control and the suction control were performed successfully in all goats. The 1/R control was performed for a long time in five goats that survived for more than 1 month. With three goats that survived for 48, 52, and 53 days mainly with the pulsatile mode, the 1/R control was stable. With a goat that survived for 73 days, the nonpulsatile mode with the 1/R control could be tested for 3 weeks. With the longest surviving goat that was maintained mainly with the pulsatile mode, the 1/R control was unstable, possibly due to the mismatching of the response time of the control system between the computer and the body. However, liver and kidney functions were almost normal, and the total protein level recovered. Further study to stabilize the 1/R control in the UPTAH is necessary.
One‐Month Biocompatibility Evaluation of the Pediatric TinyPump in Goats
Authors: Ando Yusuke , Kitao Takashi , Nagaoka Eiki , Kimura Taro , Yokoyama Yoshimasa , Yoshikawa Masaharu , Tominaga Ryuji , Takatani Setsuo
Published: August 2011

The TinyPump is an extracorporeal, magnetically driven centrifugal blood pump with its impeller suspended magnetically and hydrodynamically to provide short‐term mechanical circulatory support for children and infants. We have previously demonstrated that the in vivo experiments of the experimental TinyPump showed acceptable stable performance at pump flows averaging around 1.0 L/min with low hemolytic and thrombogenic properties for up to 2 weeks. We present here the 1‐month in vivo evaluation of the TinyPump, whose design was modified further for more durable operation. The pump was implanted as a left ventricular assist device in five goats (12.5–26.7 kg), with inflow inserted into the left ventricular apex and outflow anastomosed to the descending aorta. Five animals were supported for 110 pump days, with mean pump flow of 1.19 ± 0.03 L/min at a pump speed of 2679 ± 97 rpm. Two animals reached the scheduled end point of 30 days without device failure, and mean plasma‐free hemoglobin was 1.7 ± 0.8 mg/dL. Hematologic and biochemical data of these two animals showed no evidence of cardiovascular, renal, or hepatic dysfunction. Although further experiments are needed, the modified TinyPump offers promise as a short‐term mechanical circulatory support device in pediatric population.