bluuebunny/crossref_metadata_2025_split huggingface dataset:
Downward Migration of Coastal Conifers as a Response to Recent Land Emergence in Eastern Hudson Bay, Québec
Authors: Bégin Yves , Bérubé Dominique , Grégoire Martin 
Published: October 2002

AbstractPostglacial uplift in the eastern Hudson Bay area is among the most rapid in the world (300 m during the last 8000 yr). Although emergence curves based on 14 C-dated raised shorelines give a consistent basis for modeling relative sea-level changes, such a low-resolution dating method is inappropriate for estimating trends over recent decades. A major downward displacement of white spruce (Picea glauca (Moench) Voss) and tamarack (Larix laricina (DuRoi) K. Koch) occurred on protected shores as a response to shoreline retreat during this century. Analysis of the age distribution of trees indicates a progradation of white spruce and tamarack on gently sloping terrain ranging from 1.3 and 2.6 cm/yr, respectively, toward the sea. Improvement of climatic conditions during the 20th century favored such expansion which was probably faster than the real land emergence rates, but recent episodes of high water levels caused regression of forest margins over the highly exposed shores. Nevertheless, the downward trend of the treeline over this century substantiates the projections of 14C-dated coastal emergence curves during the modern period (1.0 to 1.3 cm/yr) by providing an estimate of the maximum rates of shoreline retreat.
Radiocarbon-Dated Pollen and Sediment Records From Near the Boylston Street Fishweir Site in Boston, Massachusetts
Authors: Newby Paige E. , Webb Thompson 
Published: October 2002

AbstractA radiocarbon-dated pollen record near the Boylston Street Fishweir site in Boston; Massachusetts, provides a regional and local record of vegetation changes from the middle Holocene to present. The stratigraphy begins about 5630 ± 90 yr B.P. with a marine transgression and is continuous up to the historic backfilling of the Back Bay area about 100 yr B.P. When pollen began accumulating at the site, the immediate area resembled the swamp forests growing today in southern New England. Fresh- and brackish-water vegetation was present before the area near the site was submerged. While these vegetation changes occurred locally, oak forest grew in the region. Correlation of this stratigraphy with archaeological data collected from 500 Boylston Street indicates that between 4700 and 3700 yr B.P., a number of fence-like alignments ("weirs"), were probably placed within existing channels and/or along shorelines to capture fish and other marine animals as they moved with the tidal flow.
Groundwater Isotopic Evidence for Paleorecharge in U.S. High Plains Aquifers
Authors: Dutton Alan R. 
Published: October 2002

AbstractCompositions of δD, δ18O,14C, and3H are distinct in unconfined and confined groundwaters beneath the nonglaciated U.S. High Plains and reflect differences in average paleoclimatic conditions between the Holocene and the Middle to Late Wisconsinan. δD and δ18O are more depleted in confined groundwaters than in unconfined groundwaters beneath the southern and central Plains but are more enriched in confined than in unconfined groundwaters beneath the northern Plains. The range in stable isotopic composition of meteoric water north-to-south across the High Plains was apparently smaller during the Middle to Late Wisconsinan than it has been during the Holocene. The greater δD and δ18O depletion of confined groundwater beneath the southern and central Plains agrees with isotopic and noble gas data on other paleowaters that suggest Middle to Late Wisconsinan recharge temperatures were cooler than average Holocene temperatures by 5 to 8°C. The greater δD and δ18O enrichment of confined groundwater beneath the northern High Plains adds to previously reported evidence for stable isotope enrichment in glacial age precipitation across the northern Plains to the eastern United States. Additional research is needed to evaluate how patterns and mechanisms of moisture transport and other climatic variables might explain isotopic composition of paleorecharge during the last glacial period.
Early Holocene Vegetation Record from the Salton Basin, California
Authors: Rinehart Roberta B. , McFarlane Donald A. 
Published: October 2002

AbstractPlant and vertebrate macrofossils in an early Holocene fossil packrat (Neotomasp.) midden with a radiocarbon age of 8640 ± 10014C yr B.P. are reported from the Chocolate Mountains, near the Salton Sea, Riverside County, California. An inventory of the midden has permitted a comparison of the modern flora and fauna of the site with that extant during the early Holocene. Whereas the biota had assumed most aspects of its modern Sonoran desert aspect by this date, statistically significant evidence of differences is attributed to an increased flow of surface water in Salt Creek, a high-standing, low-salinity Lake LeConte, and the late arrival of some characteristic Sonoran desert plants. These observations are consistent with models of significant fall-winter precipitation in the Sonoran Desert, although we cannot exclude alternative explanations.
A Continuous Holocene Glacial Record Inferred from Proglacial Lake Sediments in Banff National Park, Alberta, Canada
Authors: Leonard Eric M. , Reasoner Mel A. 
Published: October 2002

AbstractSediment cores from three proglacial lakes in northern Banff National Park, Alberta, preserve a record of Holocene glacial activity upvalley which is more continuous and better dated than available surficial records. Dating of the cores is based on tephrochronology and 16 AMS14C ages of terrestrial macrofossils. All cores contain a threefold sequence of lacustrine sediments overlying a late Pleistocene diamicton. Basal lacustrine sediments >10,10014C yr old contain little organic matter. Sediment composition indicates a large glacigenic contribution. A sharp increase in organic content marks the beginning of the Altithermal interval at all three lakes. This transition occurred abruptly at about 10,10014C yr B.P. at Crowfoot Lake and possibly more gradually at the other lakes. Altithermal sediments contain relatively little glacigenic material, and during most of the Altithermal, glaciers may have been absent above Crowfoot and Bow Lakes. Glaciers draining into Hector Lake appear to have persisted through the Altithermal. A subsequent decrease in organic content in each lake, reflecting increased clastic sedimentation, marks the end of the Altithermal and the onset of Neoglacial ice advances. The transition took place between about 5800 and 400014C yr B.P. and may be time-transgressive, beginning earlier in Hector Lake than in Crowfoot Lake. Changing Neoglacial clastic sedimentation rates through the Neoglacial interval indicate two main periods of increased glacier extent, between ca. 3000 and 1800 varve yr ago (ca. 2900–190014C yr B.P.) and during the last several hundred years. During the intervening period glaciers were less extensive, but much more extensive than during the recessions of the Altithermal interval.
Federal‐funds‐rate volatility and the reserve‐maintenance period
Authors: Eagle David 
Published: October 2002

AbstractThe day‐to‐day changes in the federal funds rate affects all banks, in particular those banks who execute their single federal funds transaction through larger correspondent banks. This paper's stochastic equilibrium model discusses how a major determinant of that behavior—the bank's reserve‐maintenance period—molds the interday pattern of federal‐funds‐rate volatility. In particular, the model explains why the volatility of the federal funds rate increases from the beginning to the end of that period. While Spindt and Hoffmeister (1988) tried to explain that increases in terms of transaction‐cost avoidance, this paper's model demonstrates that rational expectations alone will generate this effect. It also shows that lengthening the reserve‐maintenance period increases federal‐funds rate volatility on the last day of the period.
Abnormal profits and relative strength in mutual fund returns
Authors: Volkman David A. , Wohar Mark E. 
Published: October 2002

AbstractThis study investigates the relative strength in mutual fund performance by employing three different empirical methods to analyze the profitability of twenty trading strategies, based on varying evaluation horizons and investment periods. Specifically, we test for positive persistence in fund performance by focusing on the optimal weighting of past performance information. Counter to an earlier study on relative strength of fund performance, this study's results do not support the decay of performance persistence after one year. Rather, we find persistent abnormal fund returns over a one to three year investment period based on a three to four year evaluation horizon. In addition, results show that relative strength in fund performance is directly related to persistence in superior performing funds rather than a function of persistence in inferior performing funds.
The policy content of the yield curve slope
Authors: Gamber Edward N. 
Published: October 2002

AbstractThe slope of the yield curve, defined as the difference between 10 year and 3 month government bond yields, has been shown to predict both inflation and real economic activity. This paper investigates whether the forecasting ability of the yield curve slope is solely due to its relationship to monetary policy or whether it contains independent information about the future course of inflation and output growth. The predictive content of the yield curve slope is measured over three separate monetary policy regimes. The empirical results suggest that the yield curve slope contains independent predictive information about a variable only when the Federal Reserve does not react to changes in that variable.
Effects of soyabean leaflet inclination on some factors related to photosynthesis
Authors: IKEDA T. , MATSUDA R. 
Published: October 2002

Leaflet movement in soyabean (Glycine max (L.) Merr.) is considered to be an important physiological adaptation for intercepting sunlight for photosynthesis. Solar tracking may serve to increase plant production by maximizing light interception. The objective of this study was to determine the response of A (leaflet net assimilation rate), τ (stomatal conductance) and Ci (internal leaf carbon dioxide concentration) when penultimate fully expanded leaflet angles were changed. Soyabean (cv. Enrei, Maturity group VI) was planted at Niigata University, Japan, at two densities (25 and 16 plants/m2) in mid-May of 1992 and 1993. PFD (photon flux density), A, τ, and Ci were measured with a portable leaf photosynthesis instrument. The more towards vertical the leaflets were moved, the lower the PFD and A were. A measured at R5 showed no light saturation, but did show this at V13 and R3. While A measured at 09.00 h showed no saturation point, there was saturation at 12.00 h and 15.00 h at or less than 1500 μmol/m2/s. At R3 a high correlation (r = 0.89, P < 0.01) was found between PFD and A for naturally oriented leaflets, but not for horizontal ones. These results suggest that leaflet movement is an adaptation to optimize A.
Determination of the casein content in bovine milk by 31P-NMR
Authors: BELLOQUE JOSEFINA , RAMOS MERCEDES 
Published: October 2002

The relative proportion of caseins to total protein is a parameter that can be used to control the protein quality in standardised milk, an increasing tendency in dairy industries. 31P-NMR was used to analyse the casein content of milk, by the quantitation of the area under the resonances belonging to SerP, and using methylenediphosphonic acid as internal standard. This procedure yielded good results, as similar values of caseins were obtained from N Kjeldahl and NMR analysis for slightly heated milk samples. Heating at 95 °C for 15 min did not alter the casein content results. Casein content of raw, pasteurised and UHT milks (25·6±1·4, 26·4±1·8, 25·5±1·6 g casein/l milk, respectively), obtained by NMR, were not significantly different, giving an average of 25·8±1·6 g casein/l for bulk liquid milk. This work concluded that 31P-NMR could be used as an alternative method to determine casein in raw, pasteurised, dry and UHT milks.
Growth in the Sumatran elephant (Elephas maximus sumatranus) and age estimation based on dung diameter
Authors: Reilly Joanne 
Published: October 2002

AbstractThe aim of this study was to investigate age‐related growth in the Sumatran elephantElephas maximus sumatranusand to use the derived relationship to determine the age structure of the wild elephant population in Way Kambas National Park (WKNP), Sumatra. Shoulder height, forefoot circumference and diameter of dung bolus were found to be related to age of captive Sumatran elephants using the Von Bertalanffy growth function. All length measurements were highly correlated with age in the Sumatran elephant and provide growth models for determining the age structure of wild populations. Female captive elephants reached their growth plateau earlier than male elephants who continued growing throughout the ages observed. There was no clear evidence of a secondary growth spurt in male elephants. The growth model relating dung diameter to age was used to predict the age structure of the wild elephant population in WKNP from dung measured along random line transects. The wild elephant population in WKNP is young and dominated by sub‐adults (between 5 and 15 years of age). There are marked differences between the age structure of the population as revealed in the current survey and that reported from previous studies, suggesting that changes have occurred within the population in the intervening period. The use of dung diameter to predict age offers a robust field technique for use in situations where direct observations are limited, and the use of other age estimation methods is impractical. It is easily coupled with dung counts for estimating the size, age structure and biomass of elephant populations, and has considerable potential for investigating the effects of poaching on age structure and identifying where priority action should be directed in human–elephant conflict situations.
Seasonal patterns of reproduction and abundance of leaf litter frogs in a Central American rainforest
Authors: Watling James I. , Donnelly Maureen A. 
Published: October 2002

AbstractPatterns of reproductive phenology and temporal variation in species composition and age structure were investigated for a sample of terrestrial leaf litter frogs from a lowland tropical rainforest in north‐eastern Costa Rica. Recruitment of most species showed a seasonal pattern in which the growth of juveniles occurred during the dry season. The phenology of the assemblage was also seasonal, with a peak in abundance during the dry season. Variation in abundance was driven by seasonal patterns of juvenile recruitment in one species, Eleutherodactylus brandsfordii. We suggest that the timing of reproduction and patterns of frog phenology may be tied to the availability of arthropod prey items. A comparison of our data with data collected at other rainforest sites in Central America and the Amazon basin of South America indicates that patterns of recruitment and abundance, while correlated with arthropod abundance on both continents, show divergent seasonal patterns. This and other studies indicate that peaks in abundance and recruitment of juvenile frogs are concentrated in the dry season in Central America, whereas in South American rainforests, the wet season is the period of highest abundance and juvenile recruitment. We suggest that the length and severity of dry periods in the Amazon basin limits the ability of terrestrial frogs to reproduce successfully, while in Central America a more benign dry season, while strong enough to create distinct seasonal trends in the phenology of rainforest animals, is not strong enough to prohibit frogs from recruiting juveniles during the dry season.
Identity Construction in Latvia's “Singing Revolution”: Why Inter-Ethnic Conflict Failed to Occur
Authors: Ginkel John 
Published: September 2002

IntroductionAmong the nationalist revolutions that spread across Eastern Europe in the late 1980s and early 1990s, Latvia seceded from the Soviet Union through a relatively benign process marked by the virtual absence of violent conflict. Several issues were conflated in this movement. Latvia's independence was about democracy, historical redress, and national autonomy. Yet, each of these areas included an ethnic component. Would a Latvian democracy make room for Russians? Would Latvians seek revenge against Russians for the Soviet annexation of the Baltic republics? In the event of conflict between Moscow and Riga, whom would Russophone residents of Latvia support? The demographic situation of Latvia—featuring a near balance of Latvians and mostly Russophone non-Latvians at the time of independence—suggested the potential for ethnic conflict. The forecast of conflict, though, oversimplified the roles that ethnicity and national identity play in affecting political actions. The potential for conflict was predicated on the assumption that individuals naturally identify primarily with others within their ethnic group and act competitively against members of the ethnic “other.” The fact, then, that Latvians and Russians did not clash violently during Latvia's “Singing Revolution” begs the question why inter-ethnic conflict did not occur in this case. This article explains this lack of conflict by focusing on the formation of Latvian identity in the period immediately preceding independence. I argue that individuals in nationalizing states intentionally act with reference to their national identity, and this sense of national identity is not some fixed, exogenous variable. Instead, it is socially constructed. We cannot hope to explain ethnic conflict processes without first understanding the factors that drive ethnic and national identity during chaotic times of change.
An AscI Boundary Library for the Studies of Genetic and Epigenetic Alterations in CpG Islands
Authors: Dai Zunyan , Weichenhan Dieter , Wu Yue-Zhong , Hall Julia L , Rush Laura J. , Smith Laura T. , Raval Aparna , Yu Li , Kroll Daniela , Muehlisch Joerg , Frühwald Michael C. , de Jong Pieter , Catanese Joe , Davuluri Ramana V. , Smiraglia Dominic J. , Plass Christoph 
Published: October 2002

Knudson's two-hit hypothesis postulates that genetic alterations in both alleles are required for the inactivation of tumor-suppressor genes. Genetic alterations include small or large deletions and mutations. Over the past years, it has become clear that epigenetic alterations such as DNA methylation are additional mechanisms for gene silencing. Restriction Landmark Genomic Scanning (RLGS) is a two-dimensional gel electrophoresis that assesses the methylation status of thousands of CpG islands. RLGS has been applied successfully to scan cancer genomes for aberrant DNA methylation patterns. So far, the majority of this work was done using NotI as the restriction landmark site. Here, we describe the development of RLGS using AscI as the restriction landmark site for genome-wide scans of cancer genomes. The availability of AscI as a restriction landmark for RLGS allows for scanning almost twice as many CpG islands in the human genome compared with using NotI only. We describe the development of an AscI–EcoRV boundary library that supports the cloning of novel methylated genes. Feasibility of this system is shown in three tumor types, medulloblastomas, lung cancers, and head and neck cancers. We report the cloning of 178 AscI RLGS fragments via two methods by use of this library.[Supplemental material is available online at http://www.genome.org.]
Expression Profile Analysis of the Low-Oxygen Response in Arabidopsis Root Cultures[W]
Authors: Klok Erik Jan , Wilson Iain W. , Wilson Dale , Chapman Scott C. , Ewing Rob M. , Somerville Shauna C. , Peacock W. James , Dolferus Rudy , Dennis Elizabeth S. 
Published: October 2002

AbstractWe used DNA microarray technology to identify genes involved in the low-oxygen response of Arabidopsis root cultures. A microarray containing 3500 cDNA clones was screened with cDNA samples taken at various times (0.5, 2, 4, and 20 h) after transfer to low-oxygen conditions. A package of statistical tools identified 210 differentially expressed genes over the four time points. Principal component analysis showed the 0.5-h response to contain a substantially different set of genes from those regulated differentially at the other three time points. The differentially expressed genes included the known anaerobic proteins as well as transcription factors, signal transduction components, and genes that encode enzymes of pathways not known previously to be involved in low-oxygen metabolism. We found that the regulatory regions of genes with a similar expression profile contained similar sequence motifs, suggesting the coordinated transcriptional control of groups of genes by common sets of regulatory factors.
Two polymorphs of lysozyme nitrate: temperature dependence of their solubility
Authors: Legrand L. , Riès-Kautt M. , Robert M. C. 
Published: September 2002

Two crystallographic forms of lysozyme nitrate are known, namely monoclinic and triclinic. Having previously determined the temperature dependence of the solubility of the monoclinic form (0.2 M NaNO3 solutions at pH = 4.5) [Legrand et al. (2001). J. Crystal Growth
232, 244-249], we focus here on the solubility of the triclinic form. The temperature dependence of the solubility of this crystallographic form has been measured with a static light device developed in our laboratory. This device allows to observe of the dissolution of one phase and/or the occurrence of a new one by varying the temperature with a sweep rate as low as 0.6 degree/hour. The new solubility data are complemented with crystallographic data of the triclinic form for the sake of completeness. The faces of a triclinic crystal are indexed. The crystallisation enthalpy of the triclinic form is deduced from these new results. These new solubility data allow us now to discuss (1) the publishedprotocols used to obtain the monoclinic and triclinic forms of lysozyme nitrate and (2) the phase transformation.
Production trees: a compact representation of parsed programs
Authors: Waddle Vance E. 
Published: October 2002

Abstract syntax trees were devised as a compact alternative to parse trees, because parse trees are known to require excessive amounts of storage to represent parsed programs. However, the savings that abstract syntax trees actually achieve have never been precisely described because the necessary analysis has been missing. Without it, one can only measure particular cases that may not adequately represent all the possible behaviors.
We introduce a data structure, production trees, that are more compact than either abstract syntax trees or parse trees. Further, we develop the necessary analysis to characterize the storage requirements of parse trees, abstract syntax trees, and production trees and relate the size of all three to the size of the program's text. The analysis yields the parameters needed to characterize these storage behaviors over their entire range. We flesh out the analysis by measuring these parameters for a sample of “C” programs. For these programs, production trees were from 1/15 to 1/23 the size of the corresponding parse tree, l/2.7 the size of a (minimal) abstract syntax tree, and averaged only 2.83 times the size of the program text.