bluuebunny/crossref_metadata_2025_split huggingface dataset:
Coding procedures to analyse interaction patterns in educational web forums
Authors: Manca S. , Delfino M. , Mazzoni E. 
Published: March 2009

AbstractAnalysis of interaction patterns is one of the most important indicators of quality of learning in educational web forums. Social network analysis (SNA) is gradually assuming importance in the study of interaction patterns as it focuses on the analysis of the interrelationships between individuals, thus providing a holistic perspective on group performance. However, most of the studies that use SNA in computer‐supported collaborative learning scenarios derive their data from server log files, on the assumption that this data source reflects the way people really interacted online. This study, the purpose of which is to better understand the communication flows that really occur among users, challenges these assumptions through an experimental study that makes a comparison between the structural method normally used to detect the posting addressees and an approach enriched with semantic coding. Results show that this new coding schema, if compared with traditional structural coding, detected a greater number of addressees, thus allowing a greater number of postings to be included in an SNA adjacency matrix.
Learning to collaborate by collaborating: a face‐to‐face collaborative activity for measuring and learning basics about teamwork1
Authors: Cortez C. , Nussbaum M. , Woywood G. , Aravena R. 
Published: March 2009

AbstractIn today's fast‐changing business environment, teams have emerged as a requirement for business success. However, in schools and universities, students are usually not taught teamwork skills. In this paper, we introduce learning to collaborate by collaborating, a process that enables collaboration and teamwork skills to be taught and measured through face‐to‐face collaborative work and class‐wide activities supported by wirelessly connected hand‐held devices. Following a description of learning to collaborate by collaborating, we present an experimental study whose results demonstrate that participants in the process displayed improved teamwork performance. We conclude that it is possible to effectively teach collaboration skills through the use of immediate feedback provided by a supporting technology.
Age‐specific effect of heterozygosity on survival in alpine marmots, Marmota marmota
Authors: COHAS AURÉLIE , BONENFANT CHRISTOPHE , KEMPENAERS BART , ALLAINÉ DOMINIQUE 
Published: March 2009

AbstractThe fitness consequences of heterozygosity and the mechanisms underpinning them are still highly controversial. Using capture–mark–recapture models, we investigated the effects of individual heterozygosity, measured at 16 microsatellite markers, on age‐dependent survival and access to dominance in a socially monogamous mammalian species, the alpine marmot. We found a positive correlation between standardized multilocus heterozygosity and juvenile survival. However, there was no correlation between standardized multilocus heterozygosity and either survival of older individuals or access to dominance. The disappearance of a significant heterozygosity fitness correlation when individuals older than juveniles are considered is consistent with the prediction that differences in survival among individuals are maximal early in life. The lack of a correlation between heterozygosity and access to dominance may be a consequence of few homozygous individuals attaining the age at which they might reach dominance. Two hypotheses have been proposed to explain heterozygosity‐fitness correlations: genome‐wide effects reflected by all markers or local effects of specific markers linked to genes that determine fitness. In accordance with genome‐wide effects of heterozygosity, we found significant correlations between heterozygosities calculated across single locus or across two sets of eight loci. Thus, the genome‐wide heterozygosity effect seems to explain the observed heterozygosity‐fitness correlation in the alpine marmot.
Transformation of Sclerotinia sclerotiorum with the green fluorescent protein gene and fluorescence of hyphae in four inoculated hosts
Authors: De Silva A. P. , Bolton M. D. , Nelson B. D. 
Published: March 2009

To obtain a genetic marker to observe and study the interaction of Sclerotinia sclerotiorum with its hosts, isolates ND30 and ND21 were transformed using pCT74 and gGFP constructs, both containing genes for the green fluorescent protein (GFP) and hygromycin B phosphotransferase. Putative transformants were obtained using polyethylene glycol‐mediated transformation of protoplasts. Seven stable gfp transformants were identified and evaluated for fluorescence in vitro and in planta, pathogenicity and colonization of host tissues. Real‐time quantitative polymerase chain reaction detected a single copy of the gfp gene in transformants. Fluorescence was quantified directly from mycelium and protein extracted from hyphae. The seven transformants (four from ND30 and three from ND21) were pathogenic on dry bean, canola, soybean and sunflower. However, depending on the host, three transformants differed significantly (P = 0·05) in the length of lesions formed compared to the wild‐type. Hyphae fluoresced in plant tissue and could clearly be distinguished from plant cells. Infection and colonization of tissues were clearly visible with a fluorescent microscope. Transformants differed in the intensity of GFP expression both in vitro and in planta.
Involvement of snapdragon benzaldehyde dehydrogenase in benzoic acid biosynthesis
Authors: Long Michael C. , Nagegowda Dinesh A. , Kaminaga Yasuhisa , Ho Kwok Ki , Kish Christine M. , Schnepp Jennifer , Sherman Debra , Weiner Henry , Rhodes David , Dudareva Natalia 
Published: March 2009

SummaryBenzoic acid (BA) is an important building block in a wide spectrum of compounds varying from primary metabolites to secondary products. Benzoic acid biosynthesis from l‐phenylalanine requires shortening of the propyl side chain by two carbons, which can occur via a β‐oxidative pathway or a non‐β‐oxidative pathway, with benzaldehyde as a key intermediate. The non‐β‐oxidative route requires benzaldehyde dehydrogenase (BALDH) to convert benzaldehyde to BA. Using a functional genomic approach, we identified an Antirrhinum majus (snapdragon) BALDH, which exhibits 40% identity to bacterial BALDH. Transcript profiling, biochemical characterization of the purified recombinant protein, molecular homology modeling, in vivo stable isotope labeling, and transient expression in petunia flowers reveal that BALDH is capable of oxidizing benzaldehyde to BA in vivo. GFP localization and immunogold labeling studies show that this biochemical step occurs in the mitochondria, raising a question about the role of subcellular compartmentalization in BA biosynthesis.
Real‐time vision‐based detection of Rumex obtusifolius in grassland
Authors: VAN EVERT F K , POLDER G , VAN DER HEIJDEN G W A M , KEMPENAAR C , LOTZ L A P 
Published: March 2009

van Evert FK, Polder G, van der Heijden GWAM, Kempenaar C & Lotz LAP (2009). Real‐time vision‐based detection of Rumex obtusifolius in grassland. Weed Research49, 164–174.Summary Rumex obtusifolius is a common grassland weed that is hard to control in a non‐chemical way. The objective of our research was to automate the detection of R. obtusifolius as a step towards fully automated mechanical control of the weed. We have developed a vision‐based system that uses textural analysis to detect R. obtusifolius against a grass background. Image sections are classified as grass or weed using 2‐D Fourier analysis. We conducted two experiments. In the first (laboratory) experiment, we collected 28 images containing R. obtusifolius and 28 images containing only grass. Between 23 and 25 of 28 images were correctly classified (82–89%) as showing R. obtusifolius; all grass images were correctly classified as such. In the second (field) experiment, a self‐propelled platform was used to obtain five sequences of images of R. obtusifolius plants. We used the parameters that gave the best classification results in the first experiment. We found, after changing one of the algorithm’s parameters in response to prevailing light conditions, that we were able to detect R. obtusifolius in each image of each sequence. The algorithm scans a ground area of 1.5 m2 in 30 ms. We conclude that the algorithm developed is sufficiently fast and robust to eventually serve as a basis for a practical robot to detect and control R. obtusifolius in grassland.
Measurement of ascorbic acid and glutathione peroxidase activity in biological samples collected from recurrent airway obstruction affected horses and their controls.
Authors: Tan R. H. H. , Thatcher C. D. , Buechner‐Maxwell V. , Christmann U. , Crisman M. V. , Werre S. R. 
Published: March 2009

Multiple biomarkers of oxidative stress have been measured and utilized in human medicine to assess the redox status of the lung. The purpose of the study was to determine the relationships between ascorbic acid concentration in bronchoalveolar lavage fluid (BALF), and the activity of cellular glutathione peroxidase (cGPx) in red blood cells (RBC), white blood cells (WBC), and cells of BALF, to distinguish recurrent airway obstruction (RAO)‐affected horses from their matched controls. Sixteen horses in matched pairs were used: eight non‐RAO‐affected (controls) and eight RAO‐affected horses. Samples from all horses were collected at remission (S1), during environmental challenge (S2) and at recovery (S3). In RAO‐affected horses, RBC cGPx were significantly higher at all sample times (p = 0.0313 at S1, p = 0.0208 at S2, p = 0.0207 at S3). WBC cGPx activity was also greater in these horses during remission (p = 0.0128 at S1) and challenge (p = 0.0087 at S2). In the BALF, RAO‐affected horses had significantly higher cGPx activity during recovery compared to remission (p = 0.0077). BALF ascorbic acid concentration (total, free and oxidized) was not significantly different in control horses, but total (p = 0.0009) and free (p = 0.0021) forms were significantly reduced during challenge in RAO‐affected horses.The elevation in cGPx concentration suggests an up‐regulation of this redox system to combat oxidative stress as the ascorbic acid system is depleted during challenge in RAO‐affected horses. This difference supports further research into antioxidant interventions that may prevent or minimize clinical signs of RAO.
Window traps and direct observations record similar arthropod flower visitor assemblages in two mass flowering crops
Authors: Howlett B. G. , Walker M. K. , Newstrom‐Lloyd L. E. , Donovan B. J. , Teulon D. A. J. 
Published: March 2009

AbstractUnderstanding the role of unmanaged arthropod flower visitors as crop pollinators is critical if robust and reliable long‐term alternatives are to be found for honey bee pollination. However, data on pollinator assemblages can be scant. Field observation of crop flower visitors is a common data collection technique but it can be inadequate for species identification and is labour‐intensive if used across many sites. Trapping may reduce this problem, but trap performance and sampling consistency over long distances (sites separated by >100 km) are rarely examined. Window traps were designed to collect flower‐visiting arthropods from peak‐flowering onion (Allium cepa) and pak choi (Brassica rapa var. chinensis) fields across several regions throughout New Zealand. Trap efficacy was evaluated by comparing trapped samples with observations of flower visiting arthropods during the same trapping period, from dawn (6:00 to 7:00 hours) through to dusk (20:00–21:00 hours) at the same locations. Similar types of larger arthropods (length ≥3 mm) were observed and trapped within both crops, with the hymenopteran genera Apidae, Colletidae and Halictidae and the dipteran families Syrphidae, Calliphoridae, Anthomyiidae, Stratiomyidae, Sarcophagidae, Bibionidae, Tachinidae and Muscidae the most commonly recorded. The total counts of these taxa across fields were strongly correlated between the two methods; however, the ratio of trapped to observed individuals could vary greatly between taxa. Trapping allowed more arthropods to be identified to the species level and also helped record more small arthropods (body length <3 mm) when compared with observation. Window traps can be effective for assessing the relative diversity of flower visitor assemblages and the abundance of specific taxa in specific cropping systems at the regional scale, but variation in trap efficiency between arthropod taxa must be assessed for a true measure of assemblage composition.
Nursing and spirituality
Authors: Hussey Trevor 
Published: March 2009

AbstractThose matters that are judged to be spiritual are seen as especially valuable and important. For this reason it is claimed that nurses need to be able to offer spiritual care when appropriate and, to aid them in this, nurse theorists have discussed the nature of spirituality. In a recent debate John Paley has argued that nurses should adopt a naturalistic stance which would enable them to employ the insights of modern science. Barbara Pesut has criticized this thesis, especially as it is applied to palliative care. This paper re‐examines this debate with particular attention to the meaning of ‘spirituality’ and the justification for accepting spiritual and religious theories. It is argued that when we take into consideration the great diversity among religious and spiritual ideas, the lack of rational means of deciding between them when they conflict, and the practicalities of nursing, we find that a spiritual viewpoint is less useful than a naturalistic one, when offering palliative care.
Compassion and professional care: exploring the domain
Authors: Van Der Cingel Margreet 
Published: March 2009

AbstractCompassion unites people during times of suffering and distress. Unfortunately, compassion cannot take away suffering. Why then, is compassion important for people who suffer? Nurses work in a domain where human suffering is evidently present. In order to give meaning to compassion in the domain of professional care, it is necessary to describe what compassion is. The purpose of this paper is to explore questions and contradictions in the debate on compassion related to nursing care. The paper reviews classical philosophers as well as contemporary scientists' main arguments on compassion. First, I will examine the relationship between compassion and suffering. Second, how does one recognize serious suffering? This issue raises questions about the role of imagination and the need for identification. Third, literature describes compassion as an emotion. Some philosophers consider emotions uncontrollable feelings; others see a clear rational dimension in emotions. In order to determine what compassion is, it is necessary to weigh these contradictional arguments. Fourth, I will discuss motives for compassion. Is compassion an act of altruism or egoism? In this debate Nietzsche and Schopenhauer are well‐known opponents. Today, analysis of their arguments leads to some surprising conclusions. Fifth, there is the issue of fault and compassion. Can we only feel compassionate when people who suffer are not to blame for their own suffering? Such a condition faces professional caretakers with a dilemma which needs a thorough analysis if compassion is to be of use in the field of professional care. Finally, I will explore the moral meaning of compassion. Compassion, described as a concept with cognitive as well as affective dimensions, also has volitional and behavioural aspects. These aspects specifically are of importance to nursing care and further research of compassion in the nursing domain.
The anorexic agents, sibutramine and fenfluramine, depress GABAB‐induced inhibitory postsynaptic potentials in rat mesencephalic dopaminergic cells
Authors: Ledonne Ada , Sebastianelli Luca , Federici Mauro , Bernardi Giorgio , Mercuri Nicola Biagio 
Published: March 2009

Background and purpose: Nutrition is the result of a complex interaction among environmental, homeostatic and reward‐related processes. Accumulating evidence supports key roles for the dopaminergic neurons of the ventral midbrain in regulating feeding behaviour. For this reason, in the present study, we have investigated the electrophysiological effects of two centrally acting anorexic agents, fenfluramine and sibutramine, on these cells.Experimental approach: Rat midbrain slices were used to make intracellular recordings from dopaminergic neurons of the substantia nigra and the ventral tegmental area. Gamma‐aminobutyric acid (GABA)‐mediated synaptic transmission was assessed from the inhibitory postsynaptic potentials (IPSPs) mediated by GABAAand GABABreceptors.Key results: Fenfluramine and sibutramine reduced, concentration‐dependently, the GABABIPSPs, without affecting the GABAA‐mediated potentials. This effect is presynaptic, as postsynaptic membrane responses induced by application of a GABABreceptor agonist, baclofen, were not affected by the two drugs. Furthermore, the selective 5‐hydroxytriptamine 1B (5‐HT1B) receptor antagonist, SB216641, blocked the reduction of GABABIPSPs caused by fenfluramine and sibutramine, indicating that the receptor mediating this effect is 5‐HT1B.Conclusions and implications: Two anorexic agents, fenfluramine and sibutramine, induced the activation of 5‐HT1Breceptors located on presynaptic GABAergic terminals, thus reducing the release of GABA. This action can alter the strength of synaptic afferents that modify the activity of dopaminergic neurons, inducing neuronal excitation. Our results reveal an additional mechanism of action for fenfluramine and sibutramine that might contribute to reducing food intake, by influencing the pleasurable and motor aspects of feeding behaviour.
Loss of Ca2+‐mediated ion transport during colitis correlates with reduced ion transport responses to a Ca2+‐activated K+ channel opener
Authors: Hirota Christina L. , McKay Derek M. 
Published: March 2009

Background and purpose:  Epithelial surface hydration is critical for proper gut function. However, colonic tissues from individuals with inflammatory bowel disease or animals with colitis are hyporesponsive to Cl‐ secretagogues. The Cl‐ secretory responses to the muscarinic receptor agonist bethanechol are virtually absent in colons of mice with dextran sodium sulphate (DSS)‐induced colitis. Our aim was to define the mechanism underlying this cholinergic hyporesponsiveness.Experimental approach:  Colitis was induced by 4% DSS water, given orally. Epithelial ion transport was measured in Ussing chambers. Colonic crypts were isolated and processed for mRNA expression via RT‐PCR and protein expression via immunoblotting and immunolocalization.Key results:  Expression of muscarinic M3 receptors in colonic epithelium was not decreased during colitis. Short‐circuit current (ISC) responses to other Ca2+‐dependent secretagogues (histamine, thapsigargin, cyclopiazonic acid and calcium ionophore) were either absent or severely attenuated in colonic tissue from DSS‐treated mice. mRNA levels of several ion transport molecules (a Ca2+‐regulated Cl‐ channel, the intermediate‐conductance Ca2+‐activated K+ channel, the cystic fibrosis transmembrane conductance regulator, the Na+/K+‐ATPase pump or the Na+/K+/2Cl‐ co‐transporter) were not reduced in colonic crypts from DSS‐treated mice. However, protein expression of Na+/K+‐ATPase α1 subunits was decreased twofold during colitis. Activation of Ca2+‐activated K+ channels increased ISC significantly less in DSS colons compared with control, as did the protein kinase C activator, phorbol 12‐myristate 13‐acetate.Conclusions and implications:  Decreased Na+/K+‐ATPase expression probably contributes to overall epithelial hyporesponsiveness during colitis, while dysfunctional K+ channels may account, at least partially, for lack of epithelial secretory responses to Ca2+‐mediated secretagogues.
Analysing Women's Substantive Representation: From Critical Mass to Critical Actors
Authors: Childs Sarah , Krook Mona Lena 
Published: March 2009

AbstractThis article makes a case for rethinking traditional approaches to the study of legislative behaviour on behalf of women by asking (1) not when women make a difference, but how the substantive representation of women occurs; and (2) not what ‘women’ do, but what specific actors do. The first shift aims to explore the contexts, identities and attitudes that motivate and inform substantive representation. The second seeks to move beyond a focus on female legislators to identify the ‘critical actors’, male and female, who may attempt to represent women as a group. In so doing, this framework calls attention to how structure and agency interact in the substantive representation of women.
Rational Irrationality and Simulation in Environmental Politics: The Example of Climate Change
Authors: Humphrey Mathew 
Published: March 2009

AbstractDo western publics make ‘demands’ for environmental policy that they have no desire to see enacted? The thesis that they do has been put forward recently by advocates of the ‘post-ecologist’ paradigm such as Ingolfur Blühdorn. Taking the example of climate change, this article assesses survey results that provide indicative evidence that such ‘simulative’ demands may exist. I suggest that such demands are, however, best explained through conceptual tools available from game-theoretic and rational-actor models of political behaviour, in particular rational ignorance and rational irrationality, rather than with the societal-level accounts preferred by Blühdorn and others.
Endothelin inhibits cholangiocarcinoma growth by a decrease in the vascular endothelial growth factor expression
Authors: Fava Giammarco , DeMorrow Sharon , Gaudio Eugenio , Franchitto Antonio , Onori Paolo , Carpino Guido , Glaser Shannon , Francis Heather , Coufal Monique , Marucci Luca , Alvaro Domenico , Marzioni Marco , Horst Trenton , Mancinelli Romina , Benedetti Antonio , Alpini Gianfranco 
Published: March 2009

AbstractBackground: Endothelins (ET‐1, ET‐2, ET‐3) are peptides with vasoactive properties interacting with ETA and ETB receptors. ET‐1 inhibits secretin‐stimulated ductal secretion (hallmark of cholangiocyte growth) of cholestatic rats by interaction with ET receptors.Aim: The aims of the studies were to evaluate (i) the effect of ET‐1 on cholangiocarcinoma growth in Mz‐ChA‐1 cells and nude mice and (ii) whether ET‐1 regulation of cholangiocarcinoma growth is associated with changes in the expression of vascular endothelial growth factor‐A (VEGF‐A), VEGF‐C, VEGF receptor‐2 (VEGFR‐2) and VEGFR‐3.Methods: We determined the expression of ETA and ETB receptors on normal and malignant (Mz‐ChA‐1) cholangiocytes and human cholangiocarcinoma tissue and the effect of ET‐1 on the proliferation and expression of VEGF‐A, VEGF‐C (regulators of tumour angiogenesis) and its receptors, VEGFR‐2 and VEGFR‐3, in Mz‐ChA‐1 cells. In vivo, Mz‐ChA‐1 cells were injected into the flanks of athymic mice and injections of ET‐1 or saline into the tumours were performed daily. The effect of ET‐1 on tumour size, cell proliferation, apoptosis, collagen quantity and the expression of VEGF‐A and VEGF‐C and VEGFR‐2 and VEGFR‐3 were measured after 73 days.Results: Higher expression of ETA and ETB was observed in malignant compared with normal cholangiocytes. ET‐1 inhibited proliferation and VEGF‐A, VEGF‐C, VEGFR‐2 and VEGFR‐3 expression of Mz‐ChA‐1 cells. Chronic ET‐1 treatment decreased tumour volume, tumour cell proliferation and VEGF‐A and VEGF‐C expression but increased apoptosis and collagen tissue deposition compared with controls.Conclusions: Modulation of VEGF‐A and VEGF‐C (by ET‐1) may be important for managing cholangiocarcinoma growth.