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BACKGROUND: Research conducted before genotyping was possible suggested that subjects heterozygous for the genetic mutation associated with hemochromatosis absorbed nonheme iron more efficiently than did control subjects when tested with a fortified meal. Heme-iron absorption in these subjects has not been reported. OBJECTIVE: We compared the absorption of heme and nonheme iron from minimally or highly fortified test meals between HFE C282Y-heterozygous and wild-type control subjects. DESIGN: After prospective genotyping of 256 healthy volunteers, 11 C282Y-heterozygous and 12 wild-type control subjects were recruited, and their iron absorption was compared by using a hamburger test meal with or without added iron and ascorbic acid. After retrospective genotyping of 103 participants in previous iron-absorption studies, 5 C282Y-heterozygous subjects were compared with 72 wild-type control subjects. RESULTS: HFE C282Y-heterozygous subjects did not differ significantly from wild-type control subjects in their absorption of either heme or nonheme iron from minimally or highly fortified test meals. No differences were detected in blood indexes of iron status (including serum ferritin, transferrin saturation, and non-transferrin-bound iron) or in blood lipids or transaminases, but heterozygotes had significantly greater, although normal, fasting glucose concentrations than did wild-type control subjects. Compound heterozygotes (those who had both HFE C282Y and H63D mutations) absorbed more nonheme (but not heme) iron from meals with high (but not low) iron bioavailability. CONCLUSIONS: HFE C282Y-heterozygous subjects did not absorb dietary iron more efficiently, even when foods were highly fortified with iron from ferrous sulfate and ascorbic acid, than did control subjects. Iron fortification of foods should not pose an additional health risk to HFE C282Y heterozygotes. Copyright © 2004 American Society for Clinical Nutrition [ABSTRACT FROM AUTHOR]

Nanomaterials are an enabling component of the popularly labeled area of "nanotechnology," but are generally not well understood in the materials community at large. The purpose of this article is to narrow this gap by framing nanomaterials in the traditional materials science and engineering context as well as discussing some potential implications to the materials enterprise. INSET: THE DOUBLE-EDGED SWORD OF NANOMATERIALS. [ABSTRACT FROM AUTHOR]

The emergence of China as a global economic force has influenced the technical enterprise generally and a number of industries specifically. The aluminum industry is an example, with effects on consumption and demand as well as production and supply. This article reviews these areas from both a historical and future perspective. INSET: ALUMINUM CORPORATION OF CHINA. [ABSTRACT FROM AUTHOR]

Driven primarily by energy considerations, there has been a major change in the geographical distribution of primary aluminum production over the past few decades, even as the energy efficiency of the process has been improved Meanwhile, in the United States, production of aluminum from secondary sources increased nearly ten-fold. This paper discusses past and projected future trends, emphasizing the changes in energy savings potential as the industry comes to rely morn on remelting and less on primary production. [ABSTRACT FROM AUTHOR]

Worldwide cooperation is necessary for continued progress in electronic materials to meet the increasing demands of the information technology age. To stay on the current trajectory of performance improvement, fundamental technology barriers must be overcome to further increase memory capacity and microprocessor speed while simultaneously driving down cost. This article describes several global initiatives to promote advancement in electronic materials technologies. INSETS: TMS PREPARES FOR JUNE ELECTRONIC MATERIALS CONFERENCE;THE INTERNATIONAL TECHNOLOGY ROADMAP FOR SEMICONDUCTORS;INNOVATION ECOSYSTEMS. [ABSTRACT FROM AUTHOR]

We hypothesized that change in the annual population size of guano-producing seabirds (cormorant, Phalacrocorax bougainvillii; booby, Sula variegata; pelican, Pelecanus thagus) is a response to changes in primary and secondary production of the Peruvian upwelling system. We tested this hypothesis by modeling nitrate input through upwelling to the upper layers of the ocean off Peru between 6° and 14°S using data on wind stress and sea surface temperature. The model predicted the amount of carbon fixed by primary production each year from 1925 to 2000, which was then apportioned to the Peruvian anchovy ( Engraulis ringens) biomass and ultimately to the seabird population and the anchovy fishery, the largest single-species fishery on Earth. The model predicted a marked increase in primary production as a consequence of increasing wind stress. It overestimated the anchovy biomass after the collapse of the fishery in 1972, but closely predicted the growth of seabird populations from 1925 to the mid-1960s, and their decline thereafter, explaining about 94% of the variation in seabird numbers from 1925 to 2000. The model indicates the seabirds consumed 14.4% of the available anchovies and, thus, that seabirds consumed 2.3% of the new production, before the development of the anchovy fishery, and only 2.2% of the available anchovies and 0.3% of the new production after the development of the fishery. The model results clarify the roles that environmental and anthropogenic factors may have had in regulating the guano-producing seabird populations. It indicates that the growth of seabird populations from 1925 to 1955 was likely a response to increased productivity of the Peruvian upwelling system and that the subsequent drastic decline in seabird abundance was likely due to competition for food with the fishery, which caught ∼85% of the anchovies, which otherwise would have been available for the seabirds. This model also shows that an increase in oceanic primary production promotes reproductive success and population growth in higher trophic level organisms. [ABSTRACT FROM AUTHOR]

This essay examines the relationship of William Wordsworth with Charlotte Smith. Discovery of an obscure dealings with Smith by Wordsworth's family; Move of Wordsworth to acquire Smith's work "Elegiac Sonnets and Other Essays"; Influence of Smith on the works of Wordsworth as a poet.

Management of crop residues is an important consideration for reducing soil erosion and increasing soil organic carbon. Current methods of measuring residue cover are inadequate for characterizing the spatial variability of residue cover over large fields. The objectives of this research were to determine the spectral reflectance of crop residues and soils and to assess the limits of discrimination that can be expected in mixed scenes. Spectral reflectances of dry and wet crop residues plus three diverse soils were measured over the 400–2400 nm wavelength region. Reflectance values for scenes with varying proportions of crop residues and soils were simulated. Additional spectra of scenes with mixtures of crop residues, green vegetation, and soil were also acquired in corn, soybean, and wheat fields with different tillage treatments. The spectra of dry crop residues displayed a broad absorption feature near 2100 nm, associated with cellulose-lignin, that was absent in spectra of soils. Crop residue cover was linearly related (r2=0.89) to the Cellulose Absorption Index (CAI), which was defined as the relative depth of this absorption feature. Green vegetation cover in the scene attenuated CAI, but was linearly related to the Normalized Difference Vegetation Index (NDVI, r2=0.93). A novel method is proposed to assess soil tillage intensity classes using CAI and NDVI. Regional surveys of soil conservation practices that affect soil carbon dynamics may be feasible using advanced multispectral or hyperspectral imaging systems. [Copyright &y& Elsevier]

Carbon sequestration was estimated a northern mixed-grass prairie site and a sagebrush–steppe site in southeastern Wyoming using an approach that integrates remote sensing, CO2 flux measurements, and meteorological data. Net ecosystem exchange (NEE) of CO2 was measured using aircraft and ground flux techniques and was linearly related to absorbed photosynthetically active radiation (APAR). The slope of this relationship is the radiation use efficiency (ℇ = 0.51 g C/MJ APAR); there were no significant differences in the regression coefficients between the two sites. Furthermore, ecosystem chamber measurements of total respiration in 1998 and 1999 were used to develop a functional relationship with daily average temperature; the Q10 of the relationship was 2.2. Using the Advanced Very High Resolution radiometer. Normalized Difference Vegetation Index and meteorological data, annual gross primary production and respiration were calculated from 1995 to 1999 for the two sites. Overall, the sagebrush–steppe site was a net carbon sink, whereas the northern mixed-grass prairie site was in carbon balance. There was no significant relationship between NEE and APAR for a coniferous forest site, indicating this method for scaling up CO2 flux data may be only applicable to rangeland ecosystems. The combination of remote sensing with data from CO2 flux networks can be used to estimate carbon sequestration regionally in rangeland ecosystems. [ABSTRACT FROM AUTHOR]

When flowering, leafy spurge (Euphorbia esula L.) has conspicuous yellow-green bracts that are spectrally distinct from other vegetation and may be distinguished with hyperspectrai remote sensing. In July 1999, Airborne Visible Infrared Imaging Spectrometer (AVIRIS) data were acquired in northeastern Wyoming, near Devils Tower National Monument. Using the reflectance spectrum of flowering leafy spurge, leafy spurge occurrence was determined using a new method of spectral mixture analysis, Mixture Tuned Matched Filtering (MTMF). Ground reference data (146 sites) were obtained 2 weeks before and after AVIRIS overflight to test the classification accuracy of leafy spurge. For 3 land cover types: mixed prairie, riparian, and coniferous woodlands, the presence or absence leafy spurge was detected with an overall accuracy of 95% using a 0.10 threshold for detection. Differences in classification thresholds resulted in a trade-off between false positives, pixels that were mapped as leafy spurge but did not contain leafy spurge on the ground, and false negatives, areas that had leafy spurge on the ground but were not mapped as leafy spurge. Detection of leafy spurge occurrence was best for mixed prairie and riparian cover types, and somewhat less successful for conifer woodlands because of interference from tree crowns and their shadows. The advantage of the MTMF technique is it allows automated processing of hyperspectral imagery to generate accurate maps of leafy spurge occurrence. [ABSTRACT FROM AUTHOR]

The Weed Invasion Susceptibility Prediction (WISP) model was developed as an extension of the ArcView Geographic Information System to predict potential risk of invasion by individual weed species in rangelands. Existence potential was determined by comparing growth requirements of each weed species with respect to nine site characteristics obtained from geographic data layers: distance from water and disturbance sources, elevation, annual precipitation, soil texture and pH, aspect, slope, and land cover. Disturbance is important for predicting weed infestations; an innovative aspect of the WISP model is that we use data layers for transportation and energy development as an estimate of disturbance. Data from weed surveys conducted at the Jack Morrow Hills Study Area in southwestern Wyoming, USA, were used to test WISP model predictions for the occurrence of Hyoscyamus niger (black henbane), Cardaria draba (hoary cress), and Lepidium latifolium (perennial pepperweed). Data acquired from the U.S. Department of Interior, Bureau of Land Management were used to test model predictions for the occurrence of Euphorbia esula (leafy spurge) and Centaurea maculosa (spotted knapweed) for four counties in northwestern Wyoming, USA. The model accuracy, based on false-negative errors where a species was present but was predicted not to occur, averaged 89% for the five weed species. The WISP model allows land managers to predict more easily and accurately the potential for weed invasions in order to prioritize areas for detailed monitoring. [ABSTRACT FROM AUTHOR]

Climate-change induced alterations in the global distribution of cool season (C3) and warm season (C4) grasses would impact the global carbon cycle and have differing, local effects on range and agricultural production. We hypothesize that a major influence on C3/C4 distribution may be the seasonal timing of water availability with respect to the different C3 and C4 growing seasons. An algorithm expressing this hypothesis (the SAW hypothesis for Seasonal Availability of Water), estimates C3 versus C4 grass biomass from climate data. Sensitivity analysis indicated that temperatures used to delineate the start and end of the C3 and C4 grass growing seasons were more important than photosynthetic responses to temperature. To evaluate the SAW hypothesis, this algorithm was applied globally on a 1°×1° latitude–longitude grid. When compared with vegetation survey data at 141 locations in North America, Argentina, Australia, and South Africa, SAW algorithm predictions yielded an R2 of 0.71. Error resulted primarily from comparing large grid cells to plot data, interannual variability of climate, and from gridding measured climate to data-sparse locations with a single lapse rate of air temperature with elevation. Application of the SAW algorithm to a climate change scenario suggested that changes in temperature and precipitation patterns could offset C3 photosynthetic advantages offered by elevated atmospheric CO2 concentrations. These results underscored the importance of accurately representing the timing and spatial distribution as well as the magnitude of temperature and precipitation in scenarios of future climate. [Copyright &y& Elsevier]

In the late 1990s, the southeastern Bering Sea exhibited a number of anomalous conditions, including a major die-off of short-tailed shearwaters (Puffinus tenuirostris), a trans-equatorial migrant that constitutes a major portion of the marine bird biomass in the southeastern Bering Sea. As part of a larger study of the ecological role of the inner or structural front over the southeastern Bering Sea shelf, in 1997–1999, we collected short-tailed shearwaters to determine diet composition. In spring 1997, we found that short-tailed shearwaters were consuming predominately the euphausiid Thysanoessa raschii, a diet expected on the basis of past studies. However, in subsequent years, short-tailed shearwater diets in spring contained increasingly larger proportions of fish, in particular, sandlance (Ammodytes hexapterus), as well as other species of euphausiids (T. inermis in 1999). In summer and fall collections, short-tailed shearwater diets were more varied than in spring, and included both fish (age-0 gadids, 21–35% by weight) and a wider variety of euphausiid species (T. inermis and T. spinifera). In summer and fall, crab zoea (August 1998) and copepods (August 1999) were eaten by shearwaters collected while feeding within the inner front. Diets in 1997–1999 were broader than those found in previous studies of short-tailed shearwaters over the inner shelf and Bristol Bay, which had documented diets composed almost solely of T. raschii. Our data are consistent with the hypothesis that euphausiids were less available to short-tailed shearwaters foraging over the middle and coastal domains of the southeastern Bering Sea in 1997–1999 than has previously been true. Our results are also consistent with hypothesis that the inner front can affect the availability of prey to shearwaters. [Copyright &y& Elsevier]

The inner front of the southeastern Bering Sea shows marked spatial variability in frontal characteristics created by regional differences in forcing mechanisms. Differences in forcing mechanisms (sea ice advance/retreat and storm strength and timing) and early spring water properties result in strong interannual variability in biological, chemical, and physical features near the front. We have developed a simple model based on surface heat flux and water-column mixing to explain the existence of cold belts (Cont. Shelf Res. 19(14) (1999) 1833) associated with such fronts. Hydrography, fluorescence and nutrient observations show that pumping of nutrients into the euphotic zone occurs, and this can prolong primary production at the inner front. The effectiveness of this process depends on two factors: the existence of a reservoir of nutrients in the lower layer on the middle shelf and the occurrence of sufficient wind and tidal energy to mix the water column. [Copyright &y& Elsevier]

Two Bering Sea marine research programs collaborated during the final years of the 1990s to forge advances in understanding the southeastern Bering Sea pelagic ecosystem. Southeast Bering Sea Carrying Capacity, sponsored by NOAA Coastal Ocean Program, investigated processes on the middle and outer shelf and the continental slope. The Inner Front Program, sponsored by NSF, investigated processes of the inner domain and the front between the inner and middle domains. The purposes of these programs were to (1) increase understanding of the southeastern Bering Sea ecosystem, including the roles of juvenile walleye pollock, (2) investigate the hypothesis that elevated primary production at the inner front provides a summer-long energy source for the food web, and (3) develop and test annual indices of pre-recruit pollock abundance. The observations occurred during a period of unusually large variability in the marine climate, including a possible regime shift. Sea-ice cover ranged from near zero to one of the heaviest ice years in recent decades. Sea-surface temperatures reached record highs during summer 1997, whereas 1999 was noted for its low Bering Sea temperatures. Moreover, the first recorded observations of coccolithophore blooms on the shelf were realized in 1997, and these blooms now appear to be persistent. The programs’ results include an archive of physical and biological time series that emphasize large year-to-year regional variability, and an Oscillating Control Hypothesis that relates marine productivity to climate forcing. Further investigations are needed of the confluences of interannual and even intra-seasonal variability with low-frequency climate variability as potential producers of major, abrupt changes in the southeastern Bering Sea ecosystem. [Copyright &y& Elsevier]

We modeled the energy demand of seabirds in the North Water, focusing on the planktivorous dovekie (Alle alle), the dominant species in the polynya. For the dovekie we provided an estimate of carbon flux that included aspects of spatial and temporal variability. We estimated the density, diet, and carbon consumption of dovekies throughout the polynya, from the time of their arrival in mid-May until they began to migrate south in September. Our model showed that this species is responsible for 92-96% of the energy demand and therefore carbon flux to seabirds. Dovekies consumed 73.7-147 × 10³ mt C yr[sup -1] in the North Water. Average flux rates to dovekies in the polynya were 0.74 g C m[sup -2]yr[sup -1],with a maximum estimated rate of 24 mg Cm[sup -2]d[sup -1] in the eastern portion of the study area in May. However, when averaged over the entire polynya and period of occupancy, the proportion of pelagic primary production that went to dovekies was negligible (0.3-0.6%). Our observations of dovekie distribution, indicate that the major flux of carbon to seabirds occurred close inshore along the Greenland coast. There in May, carbon flux to dovekies was estimated to be 5-14% of the potential particulate export of phytoplankton. Our estimates of the spatial distribution of carbon flux to birds suggest the extraordinary importance of production along the west coast of Greenland. [ABSTRACT FROM AUTHOR]

We examine how coupling between physical and biological processes influences the production and transfer of energy to upper trophic-level species in the southeastern Bering Sea. We review time series that illustrate changes in the marine climate of the southeastern Bering Sea since the mid-1970s, particularly variability in the persistence of sea ice and the timing of its retreat. Time series (1995 – 2001) from a biophysical mooring in the middle domain of the southeastern shelf support the hypothesis that retreat of the winter sea ice before mid-March (or the failure of ice to be advected into a region) results in an open water bloom in May or June in relatively warm water (≥3°C). Conversely, when ice retreat is delayed until mid-March or later, an ice-associated bloom occurs in cold (≤0°C) water in early spring. These variations are important because the growth and production of zooplankton and the growth and survival of larval and juvenile fish are sensitive to water temperature. The Oscillating Control Hypothesis (OCH) recently proposed by , predicts that control of the abundance of forage fish, and in the case of walleye pollock (Theragra chalcogramma), recruitment of large piscivorous fish, will switch from bottom-up limitation in extended periods with late ice retreat to top-down in warmer periods when ice retreat occurs before mid-March. In support of this hypothesis, we review recent data from the southeastern Bering Sea that show 2- to 13-fold changes in copepod abundance with changes in spring water temperatures of 3 to 5°C. We also provide indirect evidence that the abundance of adult pollock on the eastern Bering Sea shelf negatively affects the abundance forage fishes (including juvenile pollock) available to top predators. Although there is evidence that pollock year-class strength is positively related to temperature, we lack the time series of pollock populations in extended periods (8 – 10 years) of cold-water blooms necessary to test the OCH. [Copyright &y& Elsevier]

Leafy spurge, Euphorbia esula L. is an adventive, perennial weed that infests approximately 1.2 million ha of land in North America. It often forms dense stands that displace native vegetation and useful forage plants on rangelands and in riparian habitats. Leafy spurge is a good candidate for detection via remote sensing because the distinctive yellow-green color of its bracts is spectrally unique when compared to co-occurring green vegetation. During 1999, Airborne Visible Infrared Imaging Spectrometer (AVIRIS) imagery was acquired in northeastern Wyoming and ground cover data were collected. Mixture tuned matched filtering (MTMF), a specialized type of spectral mixture analysis, was used to estimate leafy spurge canopy cover and map leafy spurge distribution. Overall performance of MTMF for estimating percent cover of leafy spurge for all sites was good (r2=0.69) with better performance in prairie areas (r2=0.79) and poorer performance occurring on wooded sites (r2=0.57). However, results demonstrated that in open canopies with leafy spurge in the understory, the spectral signature is sufficiently distinct to be detectable. The techniques presented here could be used for constructing leafy spurge distribution and abundance maps with satellite hyperspectral data for larger regional areas. [Copyright &y& Elsevier]

Describes the reaction of the uncharacterized rhenium(I) precursor complex with dichloromethane which leads to the formation of the monometallic rhenium(III) product. Difference in the reactivity between the meso- and rac-et,ph-P4 ligands toward single metal centers; Isomerization of the meso-et,ph-P4 ligand to its rac-et,ph-P4 diastereomer.

Describes the development of simulation models for the underwater bite-feeding and filter-feeding of Short-tailed Shearwaters on the euphausiid Thysanoessa raschii. Profiles of photosynthetically active radiation and beam attenuation; Model of visual foraging; Prey visibility and density, handling time and search volume; Model of filter-feeding.

Investigates the relationship between near-infrared reflectance at 800 nanomillimeter from leaves and characteristics of leaf structure known to affect photosynthesis in 48 species of alpine angiosperms. Plant material; Leaf measurements; Statistical analysis.

BACKGROUND: Results of cross-sectional studies suggest that in healthy people, iron absorption adapts to meet physiologic needs and stabilize iron stores, but this has not been adequately tested in longitudinal studies. OBJECTIVE: We tested whether heme- and nonheme-iron absorption decrease in response to increased iron intake and whether iron stores reach a steady state. DESIGN: In a randomized, placebo-controlled trial, heme- and nonheme-iron absorption by healthy men and women (n = 57) were measured before and after 12 wk of supplementation with 50 mg Fe/d as ferrous sulfate. Serum and fecal ferritin were measured during supplementation and for 6 mo thereafter. RESULTS: Initially, both heme- and nonheme-iron absorption were inversely associated with serum ferritin concentration. Volunteers who took iron supplements, even those with serum ferritin <21 microg/L (n = 5), adapted to absorb less nonheme iron (3.2% at week 12 compared with 5.0% at week 0, P: < 0.001) but not less heme iron from a beef-based meal. Serum ferritin concentration was slightly but significantly higher after iron supplementation than after placebo (difference = 13 ?g/L). This higher ferritin concentration persisted for >/=6 mo after supplementation, except in subjects with low iron stores, whose serum ferritin returned to baseline within 3 mo. Fecal ferritin excretion increased 2.5-fold (P: < 0.05) during supplementation. CONCLUSIONS: Healthy individuals, even those with low iron stores, had reduced nonheme-iron absorption from food in response to iron supplementation. Despite this partial adaptation, iron stores were greater after iron supplementation than after placebo and this difference was sustained, except in individuals with the lowest iron stores. Copyright © 2000 American Society for Clinical Nutrition [ABSTRACT FROM AUTHOR]

Discusses simulation techniques used in verifying microprocessor design. Details on the computational logic for access control list 2; Details on the FM9801 microprocessor; Machine proof requirements; Design invariants. INSETS: Simulation versus formal verification;ACL2.

BACKGROUND: The characteristics of vegetarian diets suggest that these diets would have lower dietary iron bioavailability than nonvegetarian diets, but there is no evidence of iron deficiency in vegetarians. OBJECTIVE: We evaluated the responsiveness of serum and fecal ferritin to differences in iron absorption from controlled lactoovovegetarian and nonvegetarian diets. DESIGN: Twenty-one women aged 20-42 y with serum ferritin concentrations from 6 to 149 microg/L consumed lactoovovegetarian and nonvegetarian weighed diets for 8 wk each (crossover design). The diets differed substantially in meat and phytic acid contents. Nonheme-iron absorption was measured from the whole diets after 4 wk by using extrinsic 59Fe and whole-body counting. Ferritin in extracts of fecal composites and in serum was measured by enzyme-linked immunosorbent assay the last 2 wk of each diet. RESULTS: Nonheme-iron absorption was less from the lactoovovegetarian diet than from the nonvegetarian diet (1.1% compared with 3.8%; P < 0.01; n = 10). Diet did not affect hemoglobin, transferrin saturation, erythrocyte protoporphyrin, or serum ferritin. Substantially less fecal ferritin was excreted with the lactoovovegetarian diet than with the nonvegetarian diet (1.1 compared with 6.0 microg/d, respectively; P < 0.01; n = 21). CONCLUSIONS: This research indicates 1) 70% lower nonheme-iron absorption from a lactoovovegetarian diet than from a nonvegetarian diet; 2) an associated decrease in fecal ferritin excretion, suggesting partial physiologic adaptation to increase the efficiency of iron absorption; and 3) an insensitivity of blood iron indexes, including serum ferritin, to substantial differences in dietary iron absorption for 8 wk. Copyright (c) 1999 American Society for Clinical Nutrition [ABSTRACT FROM AUTHOR]

Examines the role of the United States Securities and Exchange Commission in the regulation of securities market world-wide. Purpose of the global cooperation of securities commission; Efforts in achieving effective global securities regulation; Preparation for the Year 2000 date conversion crisis; Development of an international accounting standards.

Discusses a reading level concept that teachers use to help readers on their own instructional terms. Determination of reading levels as independent, instructional and frustration levels; Concept based on errors of recognition and comprehension; Transcending the frustrational level; Learning at the idea level; Features of Uninterrupted Sustained Silent Reading.

Reports on a study conducted to quantify the reliability of death certificate data concerning asthma. Review of medical records by a physician certified in allergy and pulmonology; Criteria for the diagnosis of asthma; Low sensitivity but high specificity of death certificate diagnosis of asthma as underlying cause of death.

Discusses the firearms preferences of 19th-century Native and Euroamericans at the Fort Union Trading Post National Historic Site, North Dakota. Patterns of firearm use by Fort Union inhabitants; Firearms trade at a specific archaeological site; Variations in weapon use; Accuracy of modern folklore relating to antebellum fur trade firearms preferences.

To determine the usefulness of the J-14 Hydraulic Press (Campbell Scientific, Inc., Logan, Utah, U.S.A.) in estimating leaf water potential, we calibrated the J-14 Press against a Scholander-type pressure chamber for leaves of various tree species. The species tested were; Acer saccharum, Acer negundo, Acer rubrun, Populus tremuloides, Populus grandidentata, Quercus rubra, and Brassaia actinophylla (Schefflera). The regression calibrations were linear with standard errors about the regression less than 0.1 MPa. The regression equations for the four genera were significantly different, with the yintercept increasing and the slope decreasing in order of decreasing specific leaf area (SLA). There were no significant differences between species of the calibration lines within the genera Acer and Populus. These data may indicate that leaves with lower SLA resist mechanical compression by the hydraulic press, causing the J-14 Press to be less sensitive to differences of leaf water potential. Therefore the J-14 Press is only a relative measure of leaf water status and does not measure leaf water potential. [ABSTRACT FROM AUTHOR]

Rapid escalation of fieldwork costs during the past years has required archaeologists to pursue innovative methods for maximizing the amount of fieldwork for the funds available. One of the more labor-intensive aspects of fieldwork is the recovery of cultural materials through the use of manual shaker screens. During the past several years, several archaeologists in the midwestern United States have utilized slightly modified, commercially-manufactured agricultural machines for this task. The result is a very cost-efficient method of artifact recovery which drastically reduces the amount of time spent at this task, allowing excavators to spend much more of their field time in excavation and data recording. It has also proved to be very nondestructive to artifacts passing through the machine. Instructions fir modifying and using the machine are presented. [ABSTRACT FROM AUTHOR]

This article examines the extent of domination by the large Standard Metropolitan Statistical Area baseball teams that could be expected in a competitive player market and the extent to which the degree of domination is sensitive to alternative specifications of the owner's objective function. Much of the work in the economics of professional sports has focused on the effects of special antitrust exemptions granted to baseball. A central policy issue which has received considerable attention in the theoretical literature is the allocational effects that result from monopsony practices such as baseball's reserve clause. This effectively transfers ownership rights from the player to the team owner. Professional baseball executives, as well as fans and the press, have argued that the elimination of such monopsony restrictions and the antitrust exemption granted professional baseball would lead to domination in player strengths by the large city teams and ruination of the sport. However, the analytical position in the economics literature is clear on this subject: as long as property rights are well defined and recontracting through sales of players' contracts is permissible and costless, a labor market with monopsonistic restrictions leads to the same allocation of players and relative team strengths as does a competitive labor market; only the distribution of wealth between players and owners is affected.

Presents an overview of university campus consultation through the formation of collaborative dyads. Components of the dyadic consultation model; Overview of community consultation; Approaches to community consultation; Collaboration between community centers and their college and university communities; Phases of consultation.

The impact of a part-time MBA degree on late-career earnings for professional employees of a firm is modelled using early-career earnings as a control for motivation and ability. Additional independent variables in the study include undergraduate degree quality, field of study, graduate degrees held, and previous experience. We find that the part-time degree is a worthwhile investment in human capital, particularly if the degree is completed early in an individual's career. Additionally, the value of the part-time degree compared to various full-time graduate degrees improves as the time spent in the full-time programs increases. The part-time degree remains an attractive choice under alternative assumptions for an individual to consider when making educational decisions. [ABSTRACT FROM AUTHOR]

Focuses on the role of the U.S. Commodity Futures Trading Commission in establishing speculative limits for excessive speculation. Revision of the Section 4a of the Commodity Exchange Act; Substantial increase in market volume; Increase professionalization of contract markets.

The article explains the process used to develop charts and graphs that help determine the dental maturation of a particular child for each of ten permanent teeth separately. Topics are dental radiographs, the tooth-formation norms for maxillary incisors and mandibular teeth, the ages of attainment for 14 stages of tooth development, and standard scores for children in the United States.

The article highlights a study which compared the assimilation and contrast effects between closed-minded and open-minded people. With regards to belief-discrepant communications from highly credible sources, it is believed that closed-minded people will assimilate more than open-minded people. It is also said that close-minded people will contrast belief-congruent communications from low credible sources more than the other group. However, results of the study did not support both hypothesis.