bluuebunny/crossref_metadata_2025_split huggingface dataset:
Time, Number, and History in the Maya World
Authors: Aveni Anthony 
Published: October 2002

AbstractWhat better way to understand ourselves than to compare our habits, our customs, our behavior with those of another? This is the goal of anthropology: to comprehend our own culture by reflecting it from the mirror of otherness. When most effective its results can be unsettling. Consider the possibility of discovering other ways of knowing that challenge our own - that can even cause us to doubt whether the knowledge we hold dear really constitutes the whole of the matter. When it comes to the study of time there are few cultures, past or present, worth reflecting upon that match the ancient Maya of Yucatan. They have been characterized in their classical (AD 200-900) heyday as a people preoccupied with time, obsessed by time; they were worshipers of time: "The great theme of Maya civilization is the passage of time . . ." (Thompson 1954, p. 13). "The central importance of the calendar . . . and the central importance of religion to everything else conspire to make the history of [their] calendar something of a key to the general cultural history of the region." (Edmonson 1988, p. 4). "Nothing in man's life would be set apart as being unrelated to the realm of the destinies of time" (Leon Portilla 1989, p. 222). The study of Maya time offers us the added bonus that since all pre-Columbian cultures were hermetically sealed by two oceans from outside influence prior to Hispanic contact, whatever we may glean concerning the perception of time from its artifacts offers us the unique opportunity to seek cultural universals and to address specifically whether diverse civilizations might develop similar practices and ideas in their encounters with the problem of time. This essay examines the connections between time and history,with special emphasis upon the unusual role played by the concept of number, in the ancient Maya world.The resources for such a study are many and varied. I begin with a discussion of the content of the monumental inscriptions.A major focus of Mayanists since great advances in decoding the Maya script were made in the 1970's, most texts are carved on impressive stone stelae erected about the Maya ruins, well remembered by visitors to Tikal, Copan and Calakmul. I then move on to the esoteric world of the sacred books.Though scarcely a handful of them remain, they hold the keys to the deepest understanding of what time meant to the elite daykeepers who devised them. Along the way we supplement our understanding of these texts by referring to colonial period documents and ethnological studies of contemporary cultures descended from the ancient Maya. Here we discover a remarkable continuity of culture, which greatly illuminates our understanding of the Maya past.
Krogia coralloides, a new lichen genus and species from Mauritius
Authors: Timdal Einar 
Published: October 2002

AbstractThe new corticolous lichen genus Krogia and species K. coralloidesare described from humid forest in Mauritius. The genus shows affinities with Phyllopsora, but differs in characters of the ascus, ascospores, and thallus anatomy. The ascal characters make its inclusion in the Bacidiaceae or Phyllopsoraceae problematic. The lichen contains boninic acid and an apparently related compound.
Kroswia, a new genus in the Pannariaceae (lichenized ascomycetes)
Authors: Jørgensen Per M. 
Published: October 2002

AbstractA characteristic, sterile lichen genus with homoiomerous thallus containing terpenoids is described, with one subtropical species, Kroswia crystalliferum sp. nov., occurring scattered in Africa from Kenya south to the Cape, southern India (with Sri Lanka) and Taiwan. Another temperate species, Kroswia gemmascens (Nyl.) comb, nov., is restricted to Eastern Asia. in spite of its gelatinous, homoiomerous thallus, the genus appears to belong to the Pannariaceae.
Holocene Relict Woodlands at the Eastern Canadian Treeline
Authors: Payette Serge , Morneau Claude 
Published: October 2002

AbstractWe present direct evidence for the relict nature of lichenspruce woodlands thriving at treeline, using 14C-dated stands growing in the humid climate of eastern Hudson Bay in northern Québec. Black spruce, Picea mariana (Mill.) BSP, forms two groups of relict stands: a Neoglacial group of postfire origin dating between 2000 and 900 yr B.P. and a pre-Neoglacial group most likely established between 4500 and 3200 yr B.P. The latter group shows no evidence of fire (absence of charcoal under topsoil organic horizon). The stands are exceptional because they probably are the direct lineages of the primeval forests that colonized the land sometime after deglaciation. The structure of the relict lichen-spruce communities gives strong support to the current thesis that considers lichen-spruce woodland as a self-perpetuating open forest, typical of the subarctic environment.
Climatic Implications of Macro- and Microfossil Assemblages from Late Pleistocene Deposits in Northern New Zealand
Authors: Ogden John , Newnham Rewi M. , Palmer Jonathan G. , Serra Richard G. , Mitchell Neil D. 
Published: October 2002

AbstractTwenty-two plant species were identified from leaves, fruits, or flowers, and 41 taxa from pollen, present in a macrofossil (leaf) layer in a peat swamp formed on Pleistocene dunes on the Aupouri Peninsula in northern New Zealand. Eight genera of gymnosperms are represented. With the exception of Lagarostrobos colensoi, all tree species abundant as macrofossils are also common as pollen. Macrofossils enabled the on-site flora to be compared with the regional flora, represented by the pollen rain. Studies on leaf decomposition rates indicate bias toward sclerophyllous species in the macrofossils. Identification to species level and treering data from preserved kauri logs allow quantitative comparisons with similar extant communities. Current climatic conditions at those analogue sites are cooler (2° to 3°C), cloudier (11%), and much wetter (85%) than those currently prevailing on the Aupouri Peninsula. Dendrochronological results also suggest that the far north of New Zealand had a cooler, cloudier, and wetter climate at the time the fossil leaf assemblage was formed. Radiocarbon dates from possibly contaminated samples suggest that a diverse mixed gymnosperm/angiosperm forest, dominated by kauri (Agathis australis), was present about (or sometime before) 41,00034,000 yr B.P., when the leaf layer was formed. Similar temperature reductions have been postulated for this period in New Zealand by other authors.
Neoglacial Glacier Fluctuations in the Canadian Rockies
Authors: Luckman Brian H. , Holdsworth Gerald , Osborn Gerald D. 
Published: October 2002

AbstractThe Little Ice Age was the most extensive Neoglacial glacier advance in the Canadian Rockies. Evidence of earlier, less-extensive Neoglacial glacier advances is based on wood recovered from several glacier forefields. Wood flushed out of Athabasca Glacier (7550-8230 yr B.P., three dates) and Dome Glacier (6120-6380 yr B.P., two dates) indicates that forests occurred upvalley of present glacier termini during the Hypsithermal. Detrital logs from Peyto (14 dates), Saskatchewan (3 dates), Robson (3 dates), and Yoho (1 date) Glaciers, plus in situ slumps at Peyto and Robson Glaciers, have yielded 14 C dates between 2490 and 3300 yr B.P. (12 dates between 2800 and 2990). This wood is derived from sources at or upvalley from present glacier termini and represents forests overridden by glaciers between ca. 3100 and 2500 yr B.P. (Treeline was higher than present immediately prior to this advance.) This advance, which did not extend beyond the Little Ice Age maximum position, is designated the Peyto Advance and correlated with the Tiedemann Advance in western British Columbia. Earliest Little Ice Age advances at Peyto and Robson Glaciers are dated ca. 800-600 yr B.P. at positions ca. 500 m upvalley from Little Ice Age limits.
Pollen Response-Surface Estimates of Late-Quaternary Changes in the Moisture Balance of the Northeastern United States
Authors: Webb Robert S. , Anderson Katherine H. , Webb Thompson 
Published: October 2002

AbstractQuantitative estimates of late-Quaternary climate in the northeastern United States are reconstructed from fossil pollen data to evaluate changes in the regional moisture balance inferred from water-level fluctuations. We use environmental response surfaces to calibrate modern pollen data (for 17 different taxa) to an index of effective soil moisture and mean annual precipitation. We apply these response surfaces to fossil pollen data from 60 sites in the region to reconstruct changes in soil moisture and mean annual precipitation at 3000-yr intervals from 12,000 yr B.P. to present. The mapped reconstructions of soil moisture and mean annual precipitation illustrate how the regional moisture balance of the Northeast may have changed over the last 12,000 yr in response to changing climate. Reconstructions of annual precipitation show a gradual increase from 30% below modern values at 12,000 yr B.P. to near-modern values by 6000 yr B.P. and then remain relatively constant thereafter. Reconstructed changes in the index of effective soil moisture, however, show a pattern of near-modern values at 12,000, 6000, and 3000 yr B.P., with significantly lower values estimated for 9000 yr B.P., the time of maximum pine pollen abundances in the Northeast. This pattern of change is similar to the change in regional moisture balance inferred from stratigraphic records of water-level fluctuations. These results confirm previous interpretations, based on records of water-level fluctuations, that conditions in the Northeast were significantly drier during the early to middle Holocene than at other times during the last 12,000 yr.
Transport Direction of Wisconsinan Loess in Southeastern Minnesota
Authors: Mason Joseph A. , Nater Edward A. , Hobbs Howard C. 
Published: October 2002

AbstractA study of Wisconsinan loess in part of southeastern Minnesota confirms earlier suggestions that much of the loess in this region was not derived flora the floodplain of the Mississippi River. Two Wisconsinan loess units, the Peoria Loess and Roxana Silt, occur in the study area. Peoria Loess, 1-8 m thick, fines systematically eastward from an abrupt western border toward the Mississippi. There are no apparent grain-size trends away from other adjacent rivers. Peoria Loess thickness generally decreases eastward, but is highly variable, probably because of differential erosion. Potential sources for this unit are pre-Wisconsinan sediments on the Iowan Erosion Surface immediately west of the border of thick loess and Wisconsinan glacial sources tens or hundreds of kilometers to the west. The underlying Roxana Silt, up to 1 m thick, occurs only near the Mississippi and fines away from that river. The Roxana Silt deposit could reflect aggradation of the Mississippi floodplain because of glacial activity upstream and does not have clear implications for upland vegetation near the study area. By contrast, transport of the Peoria Loess from distant glacial sources or wind erosion of upland surfaces closer to the loess deposit both imply extensive, very sparsely vegetated surfaces west of the study area when the Peoria Loess accumulated.
Atmospheric Aerosol Loading and Transport Due to the 1783-84 Laki Eruption in Iceland, Interpreted from Ash Particles and Acidity in the GISP2 Ice Core
Authors: Fiacco R. Joseph , Thordarson Thorvaldur , Germani Mark S. , Self Stephen , Palais Julie M. , Whitlow Sallie , Grootes Peter M. 
Published: October 2002

AbstractGlass shards from the A.D. 1783 Laki fissure eruption in Iceland have been identified in the GISP2 ice core from Summit, Greenland, at a level just preceding the major acidity/sulfate peak. Detailed reconstruction of ice stratigraphy, coupled with analyses of solid particles from filtered samples, indicate that a small amount of Laki ash was carried via atmospheric transport to Greenland in the summer of 1783, whereas the main aerosol precipitation occurred in the summer and early fall of 1784. Sulfate concentrations in the ice increase slightly during late summer and fall of 1783 and remain steady throughout the winter due to slow oxidation rates during this season in the Arctic. The sulfate concentration rises dramatically in the spring and summer of 1784, producing a massive sulfate peak, previously believed to have accumulated during the summer of 1783 and commonly used as the marker horizon in Greenland ice core studies. The chronology of ash and acid fallout at the GISP2 site suggests that a significant portion of the Laid eruption plume penetrated the tropopause and that aerosol generated from it remained aloft for at least 1 yr after the eruption. Based on comparisons with other glaciochemical seasonal indicators, abnormally cool conditions prevailed at Summit during the summer of 1784. This further supports the claim that a significant volume of sulfate aerosol remained in the Arctic middle atmosphere well after the eruption had ceased.
Abrupt Climatic Changes during the Last Glaciation Based on Pollen Analysis of the Abric Romani, Catalonia, Spain
Authors: Burjachs Francesc , Julià Ramon 
Published: October 2002

AbstractThe Abric Romani continental pollen record provides evidence of abrupt climate variations during the last glaciation. The pollen record reveals a pattern of high-frequency variations similar to that in ice cores as shown by oxygen isotopes or dust content. Analyses of 14 travertine samples yield coherent U-series ages in correct stratigraphic order, ranging from 40,000 to 70,000 yr. According to changes in the composition and structure of the vegetation, five paleoclimatic phases have been differentiated; the oldest, ranging from 70,200 to 65,500 yr ago, records thermophilous taxa which correspond to the last warm events of isotopic stage 5. The next phase, from 65,500 to 56,800 yr, records a cold, humid climate that correlates with isotope stage 4. During the third phase, from 56,800 to 49,500 yr, relatively warm and cold events alternate. The fourth phase, from 49,500 to 46,200 yr, records a cold, dry climate. The fifth phase, ranging from 46,200 to 40,800 yr, records a milder phase that is similar in appearance to the beginning of the Holocene.
Correlation of a Tephra Layer in Western Greece with a Late Pleistocene Eruption in the Campanian Province of Italy
Authors: St. Seymour Karen , Christanis Kimon 
Published: October 2002

AbstractThe Kalodiki fen is a 2-km2mire in a small basin within a tectonic depression in Epirus, western Greece. Since the last glaciation the basin has been occupied by a freshwater lake and has accumulated as much as 9 m of peat, which continues to form today. A 10-cm-thick, light-brown to olive fine sandy layer appears in cores at depths ranging from 2.9 to 5.7 m. The sand fraction of this layer consists mostly of pumice fragments and brown and colorless glass shards with similar major-element compositions, and it also contains crystal fragments of feldspars (mainly sanidine), ferromagnesian minerals, and probably sphene and apatite. The colorless glass has an index of refraction 1.519 ± 0.002. A sample of the overlying peat layer gave a minimum radiocarbon age of about 31,800 ± 1200 yr B.P. for the deposition of the tephra. The likely age of the tephra, its index of refraction, and its mineralogical and chemical characteristics display strong similarities to tephra from the Campanian province of Italy. Mineralogically similar tephra layers have also been reported from a peat deposit at Philippi, in northeastern Greece.
A 110,000-Yr Record of Explosive Volcanism from the GISP2 (Greenland) Ice Core
Authors: Zielinski Gregory A. , Mayewski Paul A. , Meeker L. David , Whitlow S. , Twickler Mark S. 
Published: October 2002

AbstractThe time series of volcanically produced sulfate from the GISP2 ice core is used to develop a continuous record of explosive volcanism over the past 110,000 yr. We identified ∼850 volcanic signals (700 of these from 110,000 to 9000 yr ago) with sulfate concentrations greater than that associated with historical eruptions from either equatorial or mid-latitude regions that are known to have perturbed global or Northern Hemisphere climate, respectively. This number is a minimum because decreasing sampling resolution with depth, source volcano location, variable circulation patterns at the time of the eruption, and post-depositional modification of the signal can result in an incomplete record. The largest and most abundant volcanic signals over the past 110,000 yr, even after accounting for lower sampling resolution in the earlier part of the record, occur between 17,000 and 6000 yr ago, during and following the last deglaciation. A second period of enhanced volcanism occurs 35,000–22,000 yr ago, leading up to and during the last glacial maximum. These findings further support a possible climate-forcing component in volcanism. Increased volcanism often occurs during stadial/interstadial transitions within the last glaciation, but this is not consistent over the entire cycle. Ages for some of the largest known eruptions 100,000–9000 yr ago closely correspond to individual sulfate peaks or groups of peaks in our record.
Vegetational History of a Site in the Central Amazon Basin Derived from Phytolith and Charcoal Records from Natural Soils
Authors: Piperno Dolores R. , Becker Peter 
Published: October 2002

AbstractAnalysis of phytoliths and macroscopic charcoal from natural soils near Manaus, Brazil shows that the central Amazonian terra firme forest has not been stable during the Holocene. Phytolith taxonomic composition and radiocarbon ages indicate that a closed forest has continuously existed in the area since at least 4600 yr B.P., but that forest composition and species abundance changed significantly sometime during the Holocene Epoch. There is no evidence that the vegetation experienced swidden cultivation. The distribution and dates of the charcoal in the soils indicate that forest fires between 1795 and 550 yr B.P. burned an area of about 200 hectares. Vegetational changes and fires appear to be a result of climatic drying that may have affected large areas of the Amazon Basin over the past 5000 to 7000 years. Soil phytolith analysis is a promising tool for the study of environmental history in the humid tropics and may reduce the previous dependence on lake and swamp sediments, at least for the Holocene Epoch.
Paleomagnetic Investigation of Lake Lahontan Sediments and Its Application for Dating Pluvial Events in the Northwestern Great Basin
Authors: Liddicoat Joseph C. , Coe Robert S. 
Published: October 2002

AbstractA comparison of paleomagnetic secular variation in sediment of Pleistocene Lake Lahontan in the northwestern Great Basin with secular variation in lake sediment in the Mono Basin, California, indicates that Lake Lahontan was in the valley of the Truckee River between Pyramid Lake and Wadsworth, Nevada, from about 19,000 to 13,000 yr B.P. The secular variation in older Lake Lahontan sediment in the Truckee River valley has the general features of secular variation in middle Pleistocene lacustrine sediments near Rye Patch Dam, Nevada, 125 km to the east. On the basis of field mapping and tephrochronology, the sections of older lacustrine sediments are not coeval. The apparent, but erroneous, correlation of those sediments emphasizes the need for multiple dating methods when paleomagnetic secular variation is used to date stratigraphy.
Continental Oxygen Isotopic Record of the Last 170,000 Years in Jerusalem
Authors: Frumkin Amos , Ford Derek C. , Schwarcz Henry P. 
Published: October 2002

AbstractA long radiometrically dated oxygen isotopic record of continental climatic variations since the penultimate glaciation was obtained from a stalagmite deposited in a sealed cave in Jerusalem. This record shows that speleothems have the potential of assigning dates to long- and short-term climatic events, with possible refining of Milankovitch tuning of ice and marine records which themselves are not datable. Short-term (∼1000-yr) events are very significant in the region, reaching ∼50% of glacial/interglacial fluctuations. The Mediterranean Sea was the most probable source of local precipitation throughout the last glacial cycle.
Robust beta estimation: Some empirical evidence
Authors: Fong Wai Mun 
Published: October 2002

AbstractThe effect of allowing for skewness and excess kurtosis in estimating market model betas is examined using the Generalized Student‐t (GET) Distribution. The GET Generalized the widely used Student‐t distribution by allowing for skewness as well as leptokurtosis. Using data on monthly returns of twenty‐two stocks listed on the Singapore Stock Exchange, we find that the GET provides a significantly better fit to the data than the normal distribution or the symmetric Student‐t distribution. Based on a small out‐of‐sample experiment, the GET was also found to outperform OLS and Student‐t betas in forecasting ability.
Effect of frequency of milking on yield, composition and processing quality of milk
Authors: O'BRIEN BERNADETTE , RYAN GERARD , MEANEY WILLIAM J. , McDONAGH DAVID , KELLY ALAN 
Published: October 2002

The objective was to determine the effect of once-daily milking (ODM) and omitting one evening milking each week (13TWM), in late lactation on milk production, composition and processability. Seventy-two cows were assigned to three treatments (ODM, 13TWM and twice-daily milking [TDM]) from 4 October to 12 December. Cows were on average 218 d into lactation at the start of the trial, and all cows were managed similarly throughout the trial. Milk yields and gross milk composition of cows on all treatments were measured, and milk samples for detailed compositional and processability analysis were collected from TDM and ODM treatments at two consecutive milkings and at one milking each week, respectively. Milk yield was significantly reduced (P<0.001) and milk fat and protein concentrations were increased (P<0·01) with ODM compared with TDM. Milk yield and fat and protein concentrations of milk from TDM and 13TWM herds were similar. Casein concentrations in ODM and TDM milks were similar, but ODM milk had a higher (P<0·05) whey protein content. Somatic cell count of ODM and TDM milks was similar. Rennet coagulation time (RCT) and curd firmness (A60) of milk were not affected by milking frequency. However, rate of curd aggregation (K20) of ODM milk was reduced (P<0·05) compared with that of TDM milk. Plasmin activity in ODM milk was numerically higher than in TDM milk, but the effect was not significant. ODM milk had higher NAGase activity than TDM milk (P<0·01). In conclusion, once daily milking reduced milk yield by 29% and did not adversely affect the processability of milk. Moreover, one evening milking per week could be eliminated without adverse effects on milk yield or composition.