bluuebunny/crossref_metadata_2025_split huggingface dataset:
Creating high‐frequency national accounts with state‐space modelling: a Monte Carlo experiment
Authors: Liu H. , Hall S. G. 
Published: August 2002

AbstractThis paper assesses a new technique for producing high‐frequency data from lower frequency measurements subject to the full set of identities within the data all holding. The technique is assessed through a set of Monte Carlo experiments. The example used here is gross domestic product (GDP) which is observed at quarterly intervals in the United States and it is a flow economic variable rather than a stock. The problem of constructing an unobserved monthly GDP variable can be handled using state space modelling. The solution of the problem lies in finding a suitable state space representation. A Monte Carlo experiment is conducted to illustrate this concept and to identify which variant of the model gives the best monthly estimates. The results demonstrate that the more simple models do almost as well as more complex ones and hence there may be little gain in return for the extra work of using a complex model. Copyright © 2001 John Wiley & Sons, Ltd.
Maximum Entropy in Option Pricing: A Convex‐Spline Smoothing Method
Authors: Guo Weiyu 
Published: August 2002

AbstractApplying the principle of maximum entropy (PME) to infer an implied probability density from option
prices is appealing from a theoretical standpoint because the resulting density will be the least prejudiced
estimate, as “it will be maximally noncommittal with respect to missing or unknown
information.”1 Buchen and Kelly (1996) showed that, with a set of
well‐spread simulated exact‐option prices, the maximum‐entropy distribution (MED)
approximates a risk‐neutral distribution to a high degree of accuracy. However, when random noise is
added to the simulated option prices, the MED poorly fits the exact distribution. Motivated by the
characteristic that a call price is a convex function of the option's strike price, this study suggests a
simple convex‐spline procedure to reduce the impact of noise on observed option prices before inferring
the MED. Numerical examples show that the convex‐spline smoothing method yields satisfactory empirical
results that are consistent with prior studies. © 2001 John Wiley & Sons, Inc. Jrl Fut Mark
21:819–832, 2001
S&P futures returns and contrary sentiment indicators
Authors: Simon David P. , Wiggins Roy A. 
Published: August 2002

AbstractThis article investigates the predictive power of popular market‐based sentiment measures for subsequent returns on the Standard & Poor’s (S&P) 500 futures contract over 10‐day, 20‐day, and 30‐day horizons from January 1989 through June 1999. These measures include the volatility index, the put–call ratio, and the trading index. The empirical results show that these variables over a variety of specifications frequently have statistically and economically significant forecasting power. The results indicate that these variables are contrarian indicators, consistent with the view that periods of extreme fear in the stock market have provided excellent buying opportunities. Finally, out‐of‐sample trading simulations performed over the second half of the sample period demonstrate that profits and risk‐adjusted profits would have been enhanced by buying S&P futures when the fear indicators were high rather than low. © 2001 John Wiley & Sons, Inc. Jrl Fut Mark 21:447–462, 2001
Color bar coding the BRCA1 gene on combed DNA: A useful strategy for detecting large gene rearrangements
Authors: Gad Sophie , Aurias Alain , Puget Nadine , Mairal Aline , Schurra Catherine , Montagna Marco , Pages Sabine , Caux Virginie , Mazoyer Sylvie , Bensimon Aaron , Stoppa‐Lyonnet Dominique 
Published: August 2002

AbstractGenetic linkage data have shown that alterations of the BRCA1 gene are responsible for the majority of hereditary breast and ovarian cancers. BRCA1 germline mutations, however, are found less frequently than expected. Mutation detection strategies, which are generally based on the polymerase chain reaction, therefore focus on point and small gene alterations. These approaches do not allow for the detection of large gene rearrangements, which also can be involved in BRCA1 alterations. Indeed, a few of them, spread over the entire BRCA1 gene, have been detected recently by Southern blotting or transcript analysis. We have developed an alternative strategy allowing a panoramic view of the BRCA1 gene, based on dynamic molecular combing and the design of a full four‐color bar code of the BRCA1 region. The strategy was tested with the study of four large BRCA1 rearrangements previously reported. In addition, when screening a series of 10 breast and ovarian cancer families negatively tested for point mutation in BRCA1/2, we found an unreported 17‐kb BRCA1 duplication encompassing exons 3 to 8. The detection of rearrangements as small as 2 to 6 kb with respect to the normal size of the studied fragment is achieved when the BRCA1 region is divided into 10 fragments. In addition, as the BRCA1 bar code is a morphologic approach, the direct observation of complex and likely underreported rearrangements, such as inversions and insertions, becomes possible. © 2001 Wiley‐Liss, Inc.
GPHN, a novel partner gene fused to MLL in a leukemia with t(11;14)(q23;q24)
Authors: Eguchi Mariko , Eguchi‐Ishimae Minenori , Seto Masao , Morishita Kazuhiro , Suzuki Katsuyuki , Ueda Ryuzo , Ueda Kazuhiro , Kamada Nanao , Greaves Mel 
Published: August 2002

AbstractWe report a novel MLL‐associated chromosome translocation t(11;14)(q23;q24) in a child who showed signs of acute undifferentiated leukemia 3 years after intensive chemotherapy that included the topoisomerase‐II inhibitor VP 16. Screening of a cDNA library of the patient's leukemic cells showed a novel fusion transcript between MLL and the Gephyrin (GPHN) gene on 14q24. The resulting MLL‐GPHN fusion gene encodes MLL AT hook motifs and a DNA methyltransferase homology domain fused to the C‐terminal half of Gephyrin, including a presumed tubulin binding site and a domain homologous to the Escherichia coli molybdenum cofactor biosynthesis protein MoeA. Genomic breakpoint analysis showed potential in vitro topoisomerase‐II DNA‐binding sites spanning the breakpoints in both MLL and GPHN but no flanking sequences that might mediate homologous recombination. This suggests that MLL‐GPHN may have been generated by VP 16/topoisomerase‐II–induced DNA double‐strand breaks, followed by error‐prone DNA repair via non‐homologous end joining. Gephyrin was originally identified as a submembraneous scaffold protein that anchors and immobilizes postsynaptic membrane neurotransmitter receptors to underlying cytoskeletal elements. It also is reported to bind to phosphatidylinositol 3,4,5‐triphosphate binding proteins involved in actin dynamics and downstream signaling and interacts with ATM‐related family member RAFT1. Gephyrin domains in the chimeric protein therefore could contribute novel signal sequences or might modify MLL activity by oligomerization or intracellular redistribution. © 2001 Wiley‐Liss, Inc.
Localisation of a novel region of recurrent amplification in follicular lymphoma to an ∼6.8 Mb region of 13q32‐33
Authors: Neat Michael J. , Foot Nicola , Jenner Michael , Goff Lindsey , Ashcroft Kevin , Burford Deborah , Dunham Andy , Norton Andrew , Lister T. Andrew , Fitzgibbon Jude 
Published: August 2002

AbstractFollicular lymphoma (FL) is characterised by the presence of the t(14;18)(q32;q21) and represents ∼25% of new cases of non‐Hodgkin's lymphoma. While the t(14;18) is a well‐documented rearrangement, the role of secondary cytogenetic abnormalities in the development and progression of these tumours remains unclear. Comparative genomic hybridisation was used to characterise changes in DNA copy number in tumour DNA from patients with this malignancy. The mean numbers of deletion and amplification events found in each of the 45 samples studied were 1.8 and 2.3, respectively. Regions of recurrent (>10% tumour samples) gain involved chromosomes 2p13‐16 (16%), 7 (20%), 12 (16%), 13q21‐33 (18%), 18 (27%), and X (36%) and frequent losses localised to 6q (29%) and 17p (20%). Amplification of chromosome 13 represents a novel finding in FL. The minimal amplified region was refined to a 6.8‐Mb interval of 13q32‐33 between the BAC clones 88K16 and 44H20 by fluorescence in situ hybridisation studies using metaphase chromosomes derived from tumour material. There are a number of reports in the literature suggesting that amplification of chromosome 13 also occurs in other human cancers. The location of the putative oncogene on 13q described here in follicular and transformed lymphoma may also be important in the evolution of many other malignancies. © 2001 Wiley‐Liss, Inc.
Frequent gain of chromosome 19 in megakaryoblastic leukemias detected by comparative genomic hybridization
Authors: Alvarez Sara , MacGrogan Donal , Calasanz M. Jose , Nimer Stephen D. , Jhanwar Suresh C. 
Published: August 2002

AbstractAcute megakaryocytic leukemia is a rare subtype of AML that is often difficult to diagnose; it is most commonly associated with Down syndrome in children. To identify chromosomal imbalances and rearrangements associated with acute megakaryocytic leukemia, we used G‐banding, comparative genomic hybridization (CGH), and whole chromosome painting (WCP) on a variety of primary patients' samples and leukemia cell lines. The most common abnormality was gain of chromosome 19 or arm 19q, which was detected by CGH in four of 12 (33.3%) primary samples and nine of 11 (81.8%) cell lines. In none of the primary samples was this abnormality detected by G‐banding analysis. WCP was used to define further the nature of the chromosome 19 gain in the cell lines, which was found to be due to the presence of additional 19q material on marker chromosomes or to cryptic translocations involving 19q. The most common chromosomal loss—detected only in the cell lines—was deletion of chromosomal band 13q14, which was seen in six of 11 (54.5%) cell lines. Other recurrent changes included gains of 1p, 6p, 8q, 11q, 15q, 17q, and 21q and losses of 2, 4q, 5q, 7q, 9p, and 11p. Combining conventional and molecular cytogenetic analyses defined recurrent clonal chromosomal abnormalities, which will aid in the identification of critical genes that are abnormal in acute megakaryocytic leukemia cells. © 2001 Wiley‐Liss, Inc.
Buried artifacts in stable upland sites and the role of bioturbation: A review
Authors: Balek Cynthia L. 
Published: August 2002

AbstractBurial of artifacts in Holocene soils developed in pre‐Holocene sediments on stable uplands is commonly interpreted as resulting from post‐depositional accretion of sediment. However, soils are by nature dynamic and burial or displacement of artifacts can and does occur due to “normal” syndepositional and post‐depositional biomechanical pedogenic processes. This paper presents a review of the role of bioturbation in artifact burial. © 2002 John Wiley & Sons, Inc.
A general and accurate approach for computing the statistical power of the transmission disequilibrium test for complex disease genes
Authors: Chen Wei‐Min , Deng Hong‐Wen 
Published: August 2002

AbstractTransmission disequilibrium test (TDT) is a nuclear family–based analysis that can test linkage in the presence of association. It has gained extensive attention in theoretical investigation and in practical application; in both cases, the accuracy and generality of the power computation of the TDT are crucial. Despite extensive investigations, previous approaches for computing the statistical power of the TDT are neither accurate nor general. In this paper, we develop a general and highly accurate approach to analytically compute the power of the TDT. We compare the results from our approach with those from several other recent papers, all against the results obtained from computer simulations. We show that the results computed from our approach are more accurate than or at least the same as those from other approaches. More importantly, our approach can handle various situations, which include (1) families that consist of one or more children and that have any configuration of affected and nonaffected sibs; (2) families ascertained through the affection status of parent(s); (3) any mixed sample with different types of families in (1) and (2); (4) the marker locus is not a disease susceptibility locus; and (5) existence of allelic heterogeneity. We implement this approach in a user‐friendly computer program: TDT Power Calculator. Its applications are demonstrated. The approach and the program developed here should be significant for theoreticians to accurately investigate the statistical power of the TDT in various situations, and for empirical geneticists to plan efficient studies using the TDT. Genet. Epidemiol. 21:53–67, 2001. © 2001 Wiley‐Liss, Inc.
High‐temperature, low/medium‐pressure clockwise P–T paths and melting in the development of regional migmatites: the role of crustal thickening and repeated plutonism
Authors: Jung S. 
Published: August 2002

AbstractHigh‐temperature, low/medium‐pressure (c. 700 ± 50°C, c. 5 ± 1 kbar) migmatite terranes with abundant intrusions of granite from the Proterozoic to Palaeozoic Damara Orogen (Namibia) are mostly characterized by final near‐isobaric cooling paths in which substantial decompression occurred at high temperatures prior to cooling. The thermal peak, as inferred from Grt–Bt–Pl thermobarometry obtained from in situ migmatites, was reached between c. 500 and c. 520 Ma based on U‐Pb monazite ages and Sm‐Nd garnet–whole‐rock ages. The thermal peak was reached close to or shortly after the main deformation and was followed by intrusion of A‐type and S‐type granite magmas between c. 492–488 Ma and c. 492–484 Ma, respectively. On the other hand, high‐grade metapelitic and nebulitic country rocks record U‐Pb monazite ages of c. 538 Ma, c. 520–510 Ma and c. 487–470 Ma. Available age data indicate that the metamorphic evolution of the complex was not rapid but probably polyphase. Petrological studies suggest that the area was already at high metamorphic grade (Kfs + Sil‐present, muscovite‐absent, abundant residual migmatites) before the earliest granite intrusion which crystallized between 529 and 516 Ma. These results indicate that the features of granite intrusion are superimposed upon the regional metamorphic history. This conclusion is compatible with the observation that large contact aureoles are absent. A comprehensive geochronological study from the Oetmoed Migmatite Granite Complex, situated within the high‐grade central part of the orogen, shows that low/medium‐P, high‐T metamorphism was maintained by focusing mid‐crustal heat from repeated intrusion of crustally derived granite. High‐T regional metamorphism and intrusion of water‐undersaturated high‐temperature felsic melts initiated melting reactions which ultimately led to the co‐existence of in situ and intrusion‐related migmatites. It can be inferred that in situ migmatization was syntectonic (relative to crustal thickening), whereas formation of most of the mobile granitic magmas was post‐tectonic (relative to crustal thickening). Copyright © 2000 John Wiley & Sons, Ltd.
Characterization of a novel brain‐derived microglial cell line isolated from neonatal rat brain
Authors: Cheepsunthorn Poonlarp , Radov Lesley , Menzies Sharon , Reid John , Connor James R. 
Published: August 2002

AbstractWe observed highly aggressively proliferating immortalized (HAPI) cells growing in cultures that had been enriched for microglia. The cells were initially obtained from mixed glial cultures prepared from 3‐day‐old rat brains. HAPI cells are typically round with few or no processes when cultured in 10% serum containing medium. As the percentage of serum in the medium is decreased, the HAPI cells have more processes. HAPI cells stain for the isolectin B4, OX‐42, and GLUT5, which are markers for microglial cells, but the cells do not immunolabel with A2B5, a marker of cells in the oligodendroglial cell lineage, or with the astrocyte‐specific marker, glial fibrillary aciidic protein (GFAP). In addition, HAPI cells are capable of phagocytosis. We conclude that HAPI cells are of microglia/macrophage lineage. Exposing HAPI cells to lipopolysaccharide (LPS) induces the mRNAs for tumor necrosis factor‐α (TNF‐α) and inducible nitric oxide synthase (iNOS). LPS exposure also induces secretion of TNF‐α and production of nitric oxide (NO) in HAPI cells. Because activation of microglia is associated with an increase in iron accumulation and ferritin expression, we tested the hypothesis that iron status affects the production of TNF‐α and NO. Our studies demonstrate that both iron chelation and iron loading diminished the LPS‐induced effect of TNF‐α and NO. The results of this study indicate that HAPI cells possess the characteristics of microglia/brain macrophages, providing an alternative cell culture model for the study of microglia. In addition, we demonstrate that the activation of microglial cells could be modified by iron. GLIA 35:53–62, 2001. © 2001 Wiley‐Liss, Inc.
Spatial and temporal independent component analysis of functional MRI data containing a pair of task‐related waveforms
Authors: Calhoun V.D. , Adali T. , Pearlson G.D. , Pekar J.J. 
Published: August 2002

AbstractIndependent component analysis (ICA) is a technique that attempts to separate data into maximally independent groups. Achieving maximal independence in space or time yields two varieties of ICA meaningful for functional MRI (fMRI) applications: spatial ICA (SICA) and temporal ICA (TICA). SICA has so far dominated the application of ICA to fMRI. The objective of these experiments was to study ICA with two predictable components present and evaluate the importance of the underlying independence assumption in the application of ICA. Four novel visual activation paradigms were designed, each consisting of two spatiotemporal components that were either spatially dependent, temporally dependent, both spatially and temporally dependent, or spatially and temporally uncorrelated, respectively. Simulated data were generated and fMRI data from six subjects were acquired using these paradigms. Data from each paradigm were analyzed with regression analysis in order to determine if the signal was occurring as expected. Spatial and temporal ICA were then applied to these data, with the general result that ICA found components only where expected, e.g., S(T)ICA “failed” (i.e., yielded independent components unrelated to the “self‐evident” components) for paradigms that were spatially (temporally) dependent, and “worked” otherwise. Regression analysis proved a useful “check” for these data, however strong hypotheses will not always be available, and a strength of ICA is that it can characterize data without making specific modeling assumptions. We report a careful examination of some of the assumptions behind ICA methodologies, provide examples of when applying ICA would provide difficult‐to‐interpret results, and offer suggestions for applying ICA to fMRI data especially when more than one task‐related component is present in the data.Hum. Brain Mapping 13:43–53, 2001. © 2001 Wiley‐Liss, Inc.
The relative sensitivity of willingness‐to‐pay and time‐trade‐off to changes in health status: an empirical investigation
Authors: Smith Richard D. 
Published: August 2002

AbstractThis paper directly compares the relative sensitivity of time‐trade‐off (TTO) and willingness‐to‐pay (WTP) values obtained for various levels of change in health status. This was achieved by administering a TTO and WTP survey to a population of 50 subjects, assessing their valuation of various degrees of change in health status.It was found that, overall, WTP is more sensitive than TTO in distinguishing between different dimensions of health at the same nominal level of health status (only four WTP values not significantly different, compared with eight TTO values). In addition, WTP was also more sensitive to differences in quality of life between different levels of health within each dimension (all values significantly different from each other, with TTO yielding three insignificant relationships). These results tentatively suggest, therefore, that WTP seems to be a more sensitive measure of change in health status than TTO. Copyright © 2001 John Wiley & Sons, Ltd.
Affordability and cost‐effectiveness: decision‐making on the cost‐effectiveness plane
Authors: Pedram Sendi P. , Briggs Andrew H. 
Published: August 2002

AbstractMuch recent research interest has focused on handling uncertainty in cost‐effectiveness analysis and in particular the calculation of confidence intervals for incremental cost‐effectiveness ratios (ICERs). Problems of interpretation when ICERs are negative have led to two important and related developments: the use of the net‐benefit statistic and the presentation of uncertainty in cost‐effectiveness analysis using acceptability curves. However, neither of these developments directly addresses the problem that decision‐makers are constrained by a fixed‐budget and may not be able to fund new, more expensive interventions, even if they have been shown to represent good value for money. In response to this limitation, the authors introduce the ‘affordability curve’ which reflects the probability that a programme is affordable for a wide range of threshold budgets. The authors argue that the joint probability an intervention is affordable and cost‐effective is more useful for decision‐making since it captures both dimensions of the decision problem faced by those responsible for health service budgets. Copyright © 2001 John Wiley & Sons, Ltd.
Opportunity costs and uncertainty in the economic evaluation of health care interventions
Authors: Sendi P. , Gafni A. , Birch S. 
Published: August 2002

AbstractConsiderable methodological research has been conducted on handling uncertainty in cost‐effectiveness analysis. The current literature suggests the concepts of net health benefits and cost‐effectiveness accepta‐bility curves to circumvent the technical shortcomings of cost‐effectiveness ratio statistics. However, these approaches do not provide a solution for the inherent problem that the threshold cost‐effectiveness ratio itself is unknown. The authors suggest analysing uncertainty in cost‐effectiveness analysis by directly addressing the concept of opportunity costs using the decision rule described by Birch and Gafni (1992) and introduce a new graphical framework (the ‘decision making plane’) for communicating with policy makers. Copyright © 2002 John Wiley & Sons, Ltd.