bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rethinking lifelong learning through online distance learning in Chinese educational policies, practices and research
Authors: Yang Min 
Published: September 2007

AbstractThis paper offers a critique of the Chinese philosophy of online distance learning as a means of building a lifelong learning society. Literature about lifelong learning and its implications for online distance learning is reviewed. Documents, reports and research papers are examined to explore the characteristics of the Chinese philosophy of online distance learning as reflected in the prevailing understanding and debates in the field. Phenomenological analysis, deconstructive discourse analysis and internal criticism are employed, guided by a phenomenological qualitative methodology. The critique reveals that the notion of lifelong learning is to some extent obscured in meaning in the prevailing understanding of and debates about Chinese online distance learning. Furthermore, it shows that the Chinese philosophy of online distance learning paradoxically combines a sense of overenthusiasm with a sense of underestimation associated with the potential of online distance learning in promoting lifelong learning. Also identified is the emerging development of Chinese online distance learning towards its ‘in‐depth development’, based on an increasing awareness of the necessity to enhance the quality of online distance learning through integration of educational theories with information and communication technologies (ICT). The paper calls for a new vision on ICT for learning as a necessary condition for successful incorporation of Chinese online distance learning with and into lifelong learning.
An investigation of user perceptions and attitudes towards learning objects
Authors: Lau Siong‐Hoe , Woods Peter C. 
Published: September 2007

AbstractThis study empirically evaluates the technology acceptance model drawn from Information Systems (IS) literature to investigate how user beliefs and attitudes influence learning‐object use among higher education learners by evaluating the relationships between perceived usefulness, perceived ease of use, attitude, behavioural intentions and actual use. In the study, 601 potential learning‐object users were presented with an introductory demonstration of learning objects for a Digital Systems course. Following the demonstration and practice, data on user beliefs, attitudes and intention to use learning objects were gathered, while data on actual use of learning objects was collected at the end of the semester. Subjects with prior experience using the learning objects were eliminated from further analysis, resulting in a final sample of 481 users. structural equation modelling was employed to test the hypothesised study model. The analysis showed that both the user beliefs and attitudes have significant positive relationships with behavioural intention and that behavioural intention accurately predicted the actual use of learning objects. The results extend the validity of the TAM into a learning object context and clearly pointed out that it can be used to predict users’ future behaviour.
Class Size, Teacher Hours and Educational Attainment*
Authors: Browning Martin , Heinesen Eskil 
Published: September 2007

AbstractWe employ a regression‐discontinuity design to identify effects on educational attainment after compulsory school of class size and the number of pupils per weekly teacher hour using administrative rules as instruments. We use Danish administrative panel data. Average class size is 20, about the same as in the US and most European countries. Restricting the sample to observations close to the enrolment discontinuity points where the administrative rules have greatest predictive power, instrumental variables estimates are consistently negative. Estimates from the preferred specification are marginally significant and indicate modest effects in line with earlier studies. Estimates for subgroups are less precise, but they indicate larger effects for pupils from less advantaged backgrounds.
On the Coexistence of Banks and Markets*
Authors: Gersbach Hans , Uhlig Harald 
Published: September 2007

AbstractWe examine the coexistence of banks and financial markets by studying a credit market where the qualities of investment projects are not observable and the investment decisions of entrepreneurs are not contractible. Standard banks can alleviate moral‐hazard problems, while financial markets operated by investment banks can alleviate adverse‐selection problems. In competition, standard banks are forced to increase repayments, since financial markets can attract the highest‐quality borrowers. This, in turn, increases the share of shirkers and may make lending unprofitable for standard banks. The coexistence of financial markets and standard banks is socially inefficient. The same inefficiency may occur with the entrance of sophisticated banks, operating with a combination of rating and ongoing monitoring technologies.
Optimal Monetary Policy and Sectoral Shocks: Is International Monetary Cooperation Beneficial?
Authors: Berger Wolfram 
Published: September 2007

AbstractA stochastic general‐equilibrium model is used to explore the welfare effects of optimal monetary policy and the potential benefits of policy coordination. Cross‐country perfectly symmetric shocks in the traded goods sectors and imperfectly correlated shocks in the non‐traded goods sectors are considered. In this set‐up, monetary policy may not be able to achieve efficient sectoral resource allocations within countries and avoid inefficient relative price changes across countries. Welfare gains from coordination are sizable if the shocks to the traded and non‐traded goods sectors are negatively correlated and both sectors are of roughly equal size.
Contests with Multi‐tasking*
Authors: Clark Derek J. , Konrad Kai A. 
Published: September 2007

AbstractThe standard contest model in which participants compete in a single dimension is well understood and documented. Multi‐dimension extensions are possible but are liable to increase the complexity of the contest structure, mitigating one of its main advantages: simplicity. In this paper we propose an extension in which competition ensues in several dimensions, and a competitor that wins a certain number of these is awarded a prize. The amount of information needed to run the contest is hence limited to the number of dimensions won by each player. We look at the design of this contest from the point of view of maximising effort in the contest (per dimension and totally), and show that there will be a tendency to run small contests with few dimensions. The standard Tullock model and its results are encompassed by our framework.
Early Starts, Reversals and Catch‐up in the Process of Economic Development*
Authors: Chanda Areendam , Putterman Louis 
Published: September 2007

AbstractEarly states like China and India have been experiencing more rapid economic growth in recent decades. We show that more rapid growth by early starters has been the norm in economic history, and that the “reversal of fortune” associated with the European overseas expansion was both exceptional and temporary. Not only was the post‐1500 reversal in the process of being reversed after 1960, but also the advantage conferred by early development in the latter period was considerably greater than the growth rate disadvantage that it conferred during 1500–1960, implying a rapid undoing of the first reversal.
Financial Instability under a Flexible Exchange Rate*
Authors: Besancenot Damien , Vranceanu Radu 
Published: September 2007

AbstractMany governments in developing countries contemplate the possibility of increasing the flexibility of their exchange rates despite having accumulated substantial dollar‐denominated debt. Using a model of corporate dollar debt in which the future exchange rate is uncertain, this paper studies the financial risks that might arise as a consequence of increased exchange rate flexibility. Since a firm may default on its debt either because its dollar income is too low or because investors refuse to roll over its debt, the measure of the overall risk of default should take into account both factors, as well as their interaction. Solving the model for the no‐default rational expectations equilibrium, we find that a small risk of insolvency may bring about a substantial risk of illiquidity.
Do Antitrust Laws Facilitate Collusion? Experimental Evidence on Costly Communication in Duopolies*
Authors: Andersson Ola , Wengström Erik 
Published: September 2007

AbstractBertrand supergames with non‐binding communication are used to study price formation and stability of collusive agreements on experimental duopoly markets. The experimental design consists of three treatments with different costs of communication: zero‐cost, low‐cost and high‐cost. Prices are found to be significantly higher when communication is costly. Moreover, costly communication decreases the number of messages, but more importantly, it enhances the stability of collusive agreements. McCutcheon (1997) presents an interesting application to antitrust policy by letting the cost of communication symbolize the presence of an antitrust law that prohibits firms from discussing prices. Although our experimental results do not support the mechanism of McCutcheon's (1997) argument, the findings point in the direction of her prediction that antitrust laws might work in the interest of firms.
Distribution and underground habitats of cave‐dwelling bats in China
Authors: Niu H. , Wang N. , Zhao L. , Liu J. 
Published: September 2007

AbstractTo understand the distribution and relative abundance of cave‐dwelling bats and to identify those sites that would be important for conservation of bat species, 25 underground sites that had not been previously surveyed were investigated in this 3‐year study (from December 2003 to April 2006) in Funiu Mountain of Henan province, China. Approximately 80 000 bats were recorded, representing 12 species. The most abundant species were Rhinolophus affinis, Miniopterus schreibersi and Hipposideros pratti. The roosts were evaluated for their conservation importance. The most important sites in the area are Yunhua and Nanzhao caves, which serve as hibernaculums and nursery roosts to c. 13 740 and 11 803 bats, respectively, representing seven species. By means of cluster and correspondence analysis, the distribution of bat species was different between the two sides of the mountain and was highly dependent on the size of the cave. The underground sites in the south region hosted c. 80% of the total bats, representing 11 species. The sites in the north region hosted 20% of the total bats, representing seven species. Presently, none of the caves in the region has adequate protection and some bat populations are under serious threat. Many large caves that contained large bat populations and several species of concern had been developed as tourist sites, and so some advice on protecting the most important local habitats was sought based on the assessment of the conservation status of underground sites. This paper presents basic data concerning the distribution of cave‐dwelling bats and the patterns of cave use on Funiu Mountain. The data will help local governments and policy‐makers develop suitable strategies to promote local tourisms while protecting important habitats of animal species.
Sulcal variability, stereological measurement and asymmetry of Broca's area on MR images
Authors: Keller Simon Sean , Highley John Robin , Garcia‐Finana Marta , Sluming Vanessa , Rezaie Roozbeh , Roberts Neil 
Published: September 2007

AbstractLeftward volume asymmetry of the pars opercularis and pars triangularis may exist in the human brain, frequently referred to as Broca's area, given the functional asymmetries observed in this region with regard to language expression. However, post‐mortem and magnetic resonance imaging (MRI) studies have failed to consistently identify such a volumetric asymmetry. In the present study, an analysis of the asymmetry of sulco‐gyral anatomy and volume of this anterior speech region was performed in combination with an analysis of the morphology and volume asymmetry of the planum temporale, located within the posterior speech region, in 50 healthy subjects using MRI. Variations in sulcal anatomy were documented according to strict classification schemes and volume estimation of the grey matter within the brain structures was performed using the Cavalieri method of stereology. Results indicated great variation in the morphology of and connectivity between the inferior frontal, inferior precentral and diagonal sulci. There were significant inter‐hemispheric differences in the presence of (1) the diagonal sulcus within the pars opercularis, and (2) horizontal termination of the posterior Sylvian fissure (relative to upward oblique termination), both with an increased leftward incidence. Double parallel inferior precentral sulci and absent anterior rami of the Sylvian fissure prevented stereological measurements in five subjects. Therefore volumes were obtained from 45 subjects. There was a significant leftward volume asymmetry of the pars opercularis (P = 0.02), which was significantly related to the asymmetrical presence of the diagonal sulcus (P < 0.01). Group‐wise pars opercularis volume asymmetry did not exist when a diagonal sulcus was present in both or neither hemispheres. There was no significant volume asymmetry of the pars triangularis. There was a significant leftward volume asymmetry of the planum temporale (P < 0.001), which was significantly associated with the shape of the posterior Sylvian fissure as a unilateral right or left upward oblique termination was always associated with leftward or rightward volume asymmetry respectively (P < 0.01). There was no relationship between volume asymmetries of the anterior and posterior speech regions. Our findings illustrate the extent of morphological variability of the anterior speech region and demonstrate the difficulties encountered when determining volumetric asymmetries of the inferior frontal gyrus, particularly when sulci are discontinuous, absent or bifid. When the intrasulcal grey matter of this region is exhaustively sampled according to strict anatomical landmarks, the volume of the pars opercularis is leftward asymmetrical. This manuscript illustrates the importance of simultaneous consideration of brain morphology and morphometry in studies of cerebral asymmetry.
Soluble oligomers from a non‐disease related protein mimic Aβ‐induced tau hyperphosphorylation and neurodegeneration
Authors: Vieira Marcelo N. N. , Forny‐Germano Letícia , Saraiva Leonardo M. , Sebollela Adriano , Martinez Ana M. Blanco , Houzel Jean‐Christophe , De Felice Fernanda G. , Ferreira Sérgio T. 
Published: September 2007

AbstractProtein aggregation and amyloid accumulation in different tissues are associated with cellular dysfunction and toxicity in important human pathologies, including Alzheimer’s disease and various forms of systemic amyloidosis. Soluble oligomers formed at the early stages of protein aggregation have been increasingly recognized as the main toxic species in amyloid diseases. To gain insight into the mechanisms of toxicity instigated by soluble protein oligomers, we have investigated the aggregation of hen egg white lysozyme (HEWL), a normally harmless protein. HEWL initially aggregates into β‐sheet rich, roughly spherical oligomers which appear to convert with time into protofibrils and mature amyloid fibrils. HEWL oligomers are potently neurotoxic to rat cortical neurons in culture, while mature amyloid fibrils are little or non‐toxic. Interestingly, when added to cortical neuronal cultures HEWL oligomers induce tau hyperphosphorylation at epitopes that are characteristically phosphorylated in neurons exposed to soluble oligomers of the amyloid‐β peptide. Furthermore, injection of HEWL oligomers in the cerebral cortices of adult rats induces extensive neurodegeneration in different brain areas. These results show that soluble oligomers from a non‐disease related protein can mimic specific neuronal pathologies thought to be induced by soluble amyloid‐β peptide oligomers in Alzheimer’s disease and support the notion that amyloid oligomers from different proteins may share common structural determinants that would explain their generic cytotoxicities.
NMDA‐mediated release of glutamate and GABA in the subthalamic nucleus is mediated by dopamine: an in vivo microdialysis study in rats
Authors: Ampe Ben , Massie Ann , D’Haens Jean , Ebinger Guy , Michotte Yvette , Sarre Sophie 
Published: September 2007

AbstractThe present study investigated the effects of N‐methyl‐D‐aspartic acid·H2O (NMDA) on the dopamine, glutamate and GABA release in the subthalamic nucleus (STN) by using in vivo microdialysis in rats. NMDA (100 μmol/L) perfused through the microdialysis probe evoked an increase in extracellular dopamine in the STN of the intact rat of about 170%. This coincided with significant increases in both extracellular glutamate (350%) and GABA (250%). The effect of NMDA perfusion on neurotransmitter release at the level of the STN was completely abolished by co‐perfusion of the selective NMDA‐receptor antagonist MK‐801 (10 μmol/L), whereas subthalamic perfusion of MK‐801 alone had no effect on extracellular neurotransmitter concentrations. Furthermore, NMDA induced increases in glutamate were abolished by both SCH23390 (8 μmol/L), a selective D1 antagonist, and remoxipride (4 μmol/L), a selective D2 antagonist. The NMDA induced increase in GABA was abolished by remoxipride but not by SCH23390. Perfusion of the STN with SCH23390 or remoxipride alone had no effect on extracellular neurotransmitter concentrations. The observed effects in intact animals depend on the nigral dopaminergic innervation, as dopamine denervation, by means of 6‐hydroxydopamine lesioning of the substantia nigra, clearly abolished the effects of NMDA on neurotransmitter release at the level of the STN. Our work points to a complex interaction between dopamine, glutamate and GABA with a crucial role for dopamine at the level of the STN.
Characterization of the adaptor protein ARH expression in the brain and ARH molecular interactions
Authors: Mameza Marie Germaine , Lockard Jon M. , Zamora Eduardo , Hillefors Mi , Lavina Zeno Scotto , Kaplan Barry B. 
Published: September 2007

AbstractPreviously, pA134 was identified as one of the mRNAs present in the squid giant axon. Comparative sequence analyses revealed that the pA134 gene product manifested significant similarity to the mammalian lipoprotein receptor adaptor protein also known as ARH (autosomal recessive hypercholesterolemia). ARH mRNA and protein displayed very similar pattern of expression throughout the mouse brain. Significant levels of expression were observed in cells with a predominantly neuronal profile in the cerebellum, brainstem, olfactory bulb, hippocampus, and cortex. A yeast two hybrid screen for ARH protein interactions in mouse brain identified the following binders: amyloid precursor‐like protein 1, low density lipoprotein receptor‐related protein (LRP) 1, LRP8, and GABA receptor‐associated protein‐like 1. The interactions of ARH with LRP1 and GABA receptor‐associated protein‐like 1 were subsequently verified by co‐immunoprecipitation of the protein complexes from transfected human embryonic kidney cells. The presence of ARH mRNA in axon of primary sympathetic neurons was established by RT‐PCR analyses and confirmed by in situ hybridization. Taken together, our data suggest that ARH is a multifunctional protein whose spectrum of function in the brain goes beyond the traditionally known metabolism of lipoproteins, and that ARH may be locally synthesized in the axon.
Phosphorylation and activation of tryptophan hydroxylase 2: identification of serine‐19 as the substrate site for calcium, calmodulin‐dependent protein kinase II
Authors: Kuhn Donald M. , Sakowski Stacey A. , Geddes Timothy J. , Wilkerson Curtis , Haycock John W. 
Published: September 2007

AbstractTryptophan hydroxylase (TPH) is the initial and rate‐limiting enzyme in the biosynthesis of serotonin. TPH was once thought to be a single‐gene product but it is now known to exist in two isoforms. TPH1 is found in the periphery and pineal gland whereas TPH2 is expressed specifically in the CNS. Both TPH isoforms are known to be regulated by protein kinase‐dependent phosphorylation and the sites of modification of TPH1 by protein kinase A have been identified. While TPH2 is activated by calcium, calmodulin‐dependent protein kinase II (CaMKII), the sites at which this isoform is modified are not known. Treatment of wild‐type TPH2 with CaMKII followed by mass spectrometry analysis revealed that the enzyme was activated and phosphorylated at a single site, serine‐19. Mutagenesis of serine‐19 to alanine did not alter the catalytic function of TPH2 but this mutant enzyme was neither activated nor phosphorylated by CaMKII. A phosphopeptide bracketing phosphoserine‐19 in TPH2 was used as an antigen to generate polyclonal antibodies against phosphoserine‐19. The antibodies are highly specific for phosphoserine‐19 in TPH2. The antibodies do not react with wild‐type TPH2 or TPH1 and they do not recognize phophoserine‐58 or phosphoserine‐260 in TPH1. These results establish that activation of TPH2 by CaMKII is mediated by phosphorylation of serine‐19 within the regulatory domain of the enzyme. Production of a specific antibody against the CaMKII phosphorylation site in TPH2 represents a valuable tool to advance the study of the mechanisms regulating the function of this important enzyme.
Single molecule profiling of tau gene expression in Alzheimer’s disease
Authors: Conrad Chris , Zhu Jun , Conrad Cintia , Schoenfeld David , Fang Zhide , Ingelsson Martin , Stamm Stefan , Church George , Hyman Bradley T. 
Published: September 2007

AbstractTau is a microtubule‐associated protein that is important for establishing and maintaining neuronal morphology. In addition to its role in normal cells, tau protein is involved in many neurodegenerative diseases, e.g. Alzheimer’s disease (AD) and frontotemporal dementia, as the main component of intraneuronal aggregates. Alternative splicing of tau gene in the brain can give rise to at least six protein variants. A causative role of skewed tau exon 10 inclusion has been defined in frontotemporal dementia; however, no link was established between the aberrant splicing of tau and AD. Here, we applied a single‐molecule‐based technology, polymerase colony or polony, to simultaneously monitor tau splicing variant and haplotype profile in sporadic AD and normal brains. We found that the coordinated expression of tau exons 2 and 10 is altered in AD. Additional investigations of cis and trans mechanisms of this observation revealed a decreased protein expression of a known tau splicing factor, htra2‐beta‐1 in AD, thereby implicating a trans mechanism. Our results demonstrate that dysregulation of combinatorial splicing might serve as a signature for aging‐related diseases, and the polony assay could be widely adapted for the study of other tauopathies. Furthermore, splicing‐based therapeutics is an emerging area of drug development, and a well‐defined and quantitative assay for monitoring single‐gene transcriptome will be relevant for such development.