Evaluating the Potential Effects of Deicing Salts on Roadside Carbon Sequestration

This project sought to document patterns of road deicing salts and the effects of these salts on the amount of carbon being sequestered passively along Montana Department of Transportation roads; it was designed collaboratively with a related roadside project that tested three different highway right-of-way management techniques (mowing height, shrub planting, disturbance) to determine whether they have the capacity to increase soil organic carbon. Our sampling did not reveal elevated salt levels at any of the nine locations sampled at each of the three I-90 sites. The greatest saline concentrations were found at the sample locations farthest from the road. This pattern was consistent across all three sites. The range of soil organic matter (SOM) was broad, from ~1% to >10%. Generally, SOM values were lowest adjacent to the road and highest farthest from the road. We found no or weak evidence of a relationship between our indices of soil salinity and SOM levels, with electrical conductivity, exchangeable calcium, and cation exchange capacity. Results imply that if road deicing salts are altering patterns of roadside SOM and potential carbon sequestration, this effect was not captured by our experimental design, nor did deicing salts appear to have affected roadside vegetation during our most recent sampling effort. Our findings highlight the value of experimentally separating the multiple potentially confounding effects of winter maintenance operations on roadside soils: roads could focus the flow of water, salts, and sands to roadside soils. How these types of mass inputs to roadside soils might influence medium- or long-term carbon dynamics remains an open question, but their fuller characterization and possible flow paths will be essential to clarifying the role of roadside soils in terrestrial soil organic carbon sequestration strategies

Relative calorific value of some coals on Kansas markets

Citation: Fay, Scott Stuart. Relative calorific value of some coals on Kansas markets. Senior thesis, Kansas State Agricultural College, 1905.Morse Department of Special CollectionsIntroduction: The fuel value of coals, while it is a subject that hitherto has attracted but little attention, is one that the engineers of today are beginning to consider seriously; but it is not only these thoughtful engineers that are wide awake to the question, but practically all scientists as well, and even many coal dealers, and to a less extent the general public. Ordinarily coal is priced not on its real or its practical value as a producer of heat, but on an entirely different basis, namely, the cost necessary to lay it down, on the market. After calculating the expenditure, of wealth in mining, transportation, storing and a reasonable: profit for all concerned, and considering nothing more its market value is determined. Now this, while it must need be borne in mind, is not the principal item be used in ascertaining their commercial values. Since coal is used for the production of energy the all-important question in rating the article should be how much energy will it produce compared with others? It is to be hoped that further investigation will revise this, and give us a more scientific price list. Certainly it would be a valuable piece of work that would assign each its proper place in the system. It is the object of this experiment to arrive at some conclusions regarding the calorific value of a few coals on Kansas markets. Of the fourteen samples used thirteen were obtained from the dealers, while the other one the college coal coming from Lansing is not on the market at all. Sampling was done in the manner about to be described: A sample filling an ordinary coal bucket was taken from various parts of the bin. This was broken into small pieces, not larger than walnuts, and then spread out upon the sampling table, letting each shovel- full fall upon the same spot giving each particle an equal opportunity to roll in the direction and to the distance it would

“Not So Fast! Let’s Find Your Optimal Delivery Time!”: The Impact of Delivery Time on Retailer Profit in a Heterogeneous Market

In order to make online shopping more attractive to consumers, many retailers have endeavored to reduce the time between when an order is placed and when it is received. The cost of delivery and logistical challenges are obvious impediments to faster delivery. In this paper, we examine how other factors, including the presence of physical channels and consumer heterogeneity (in shopping preferences and product valuations), impact the optimal delivery time. To isolate the effects of these alternative factors, we ask whether faster delivery is always profitable even if it is costless to the firm and if there is no logistical impediment. (Removing these two assumptions only strengthens our results.) We contribute to the extant literature by being the first (to the best of our knowledge) to demonstrate that shipping time can be used to segment a market more efficiently and to identify how heterogeneity in consumers’ preferences for online vs. offline shopping impact the optimal shipping time (which, in turn, alters the resulting mix of online and offline sales). More specifically, we use a stylized analytical model to study how delivery time affects the profit of a multi-channel retailer who operates an online store as well as physical stores in two different cities. In accordance with prevailing wisdom, we show that delaying delivery cannot enhance a retailer’s profit if the two cities are homogenous. However, interestingly, we find that it can be profitable for the retailer to delay delivery if the two cities are heterogeneous (even though there are not any cost savings from longer delivery times). In particular, this Delayed Delivery strategy is optimal if (a) consumers’ travel costs to the physical store are small, but not too small, (b) there is large heterogeneity in consumer valuations across the two cities, and (c) high-value customers experience substantially higher disutility from shopping online than do low-value consumers. We find that consideration of the Delayed Delivery strategy has important implications for retailers. In particular, by delaying delivery, a retailer who previously only operated physical stores may find that opening an online channel would be profitable (whereas an online channel would not have been desirable if there were not any delay in delivery). Conversely, a multi-channel retailer may find that opening additional physical stores becomes advantageous if delivery from the online store is delayed. Furthermore, delaying delivery can alter whether the online store should target low-value consumers, high-value ones, or both types of consumers. Finally, counterintuitively, we show that the Delayed Delivery strategy can lead to higher consumers’ surplus, so that a win-win scenario is created because both the firm and consumers benefit from online orders being delivered less promptly

Identification of functional transcription factor binding sites using closely related Saccharomyces species

Comparative genomics provides a rapid means of identifying functional DNA elements by their sequence conservation between species. Transcription factor binding sites (TFBSs) may constitute a significant fraction of these conserved sequences, but the annotation of specific TFBSs is complicated by the fact that these short, degenerate sequences may frequently be conserved by chance rather than functional constraint. To identify intergenic sequences that function as TFBSs, we calculated the probability of binding site conservation between Saccharomyces cerevisiae and its two closest relatives under a neutral model of evolution. We found that this probability is <5% for 134 of 163 transcription factor binding motifs, implying that we can reliably annotate binding sites for the majority of these transcription factors by conservation alone. Although our annotation relies on a number of assumptions, mutations in five of five conserved Ume6 binding sites and three of four conserved Ndt80 binding sites show Ume6- and Ndt80-dependent effects on gene expression. We also found that three of five unconserved Ndt80 binding sites show Ndt80-dependent effects on gene expression. Together these data imply that although sequence conservation can be reliably used to predict functional TFBSs, unconserved sequences might also make a significant contribution to a species' biology

Frequent Gain and Loss of Functional Transcription Factor Binding Sites

Cis-regulatory sequences are not always conserved across species. Divergence within cis-regulatory sequences may result from the evolution of species-specific patterns of gene expression or the flexible nature of the cis-regulatory code. The identification of functional divergence in cis-regulatory sequences is therefore important for both understanding the role of gene regulation in evolution and annotating regulatory elements. We have developed an evolutionary model to detect the loss of constraint on individual transcription factor binding sites (TFBSs). We find that a significant fraction of functionally constrained binding sites have been lost in a lineage-specific manner among three closely related yeast species. Binding site loss has previously been explained by turnover, where the concurrent gain and loss of a binding site maintains gene regulation. We estimate that nearly half of all loss events cannot be explained by binding site turnover. Recreating the mutations that led to binding site loss confirms that these sequence changes affect gene expression in some cases. We also estimate that there is a high rate of binding site gain, as more than half of experimentally identified S. cerevisiae binding sites are not conserved across species. The frequent gain and loss of TFBSs implies that cis-regulatory sequences are labile and, in the absence of turnover, may contribute to species-specific patterns of gene expression

Podokinetic stimulation causes shifts in perception of straight ahead

Podokinetic after-rotation (PKAR) is a phenomenon in which subjects inadvertently rotate when instructed to step in place after a period of walking on a rotating treadmill. PKAR has been shown to transfer between different forms of locomotion, but has not been tested in a non-locomotor task. We conducted two experiments to assess effects of PKAR on perception of subjective straight ahead and on quiet standing posture. Twenty-one healthy young right-handed subjects pointed to what they perceived as their subjective straight ahead with a laser pointer while they were recorded by a motion capture system both before and after a training period on the rotating treadmill. Subjects performed the pointing task while standing, sitting on a chair without a back, and a chair with a back. After the training period, subjects demonstrated a significant shift in subjective straight ahead, pointing an average of 29.1 ± 10.6 degrees off of center. The effect was direction-specific, depending on whether subjects had trained in the clockwise or counter-clockwise direction. Postures that limited subjects’ ability to rotate the body in space resulted in reduction, but not elimination, of the effect. The effect was present in quiet standing and even in sitting postures where locomotion was not possible. The robust transfer of PKAR to non-locomotor tasks, and across locomotor forms as demonstrated previously, is in contrast to split-belt adaptations that show limited transfer. We propose that, unlike split-belt adaptations, podokinetic adaptations are mediated at supraspinal, spatial orientation areas that influences spinal-level circuits for locomotion

The Struck-and-lost Factor in Alaskan Walrus Harvests, 1952-1972

Struck-and-lost rates during hunts for walruses, Odobenus rosmarus (Linnaeus), in Alaska from 1952 to 1972 did not vary from year to year. On average, 42% of the animals struck by bullets were lost (i.e., not retrieved). About 55% of the struck-and lost animals died immediately; the rest were wounded. Apparently, most of the wounded died soon after they were struck. The sex-age composition of the struck-and-lost animals was about the same as that in the harvest, and the proportion lost did not vary with the size of the group encountered. Claims of reduction in loss rates in recent years, based on improved firepower, are open to question. Considerable improvement in weapons took place also during the 21-year period of this study, but it merely increased the proportion of outright kills among the struck-and-lost animals. It did not reduce the proportion lost of the animals that were struck.Key words: walrus, Odobenus rosmarus, Alaska, harvests, struck-and-lostLe taux d'animaux frapp&eacute;s et perdus au cours de la chasse au morse, Odobenus rosmarus (Linnaeus) en Alaska de 1952 &agrave; 1972 n'a pas vari&eacute; d'une ann&eacute;e &agrave; l'autre. En moyenne, 42 p. cent des animaux frapp&eacute;s par les balles ont &eacute;t&eacute; perdus (c.-&agrave;-d. non r&eacute;cup&eacute;r&eacute;s). Environ 55 p. cent des animaux frapp&eacute;s et perdus sont morts sur le coup et 45 p. cent ont &eacute;t&eacute; bless&eacute;s. Il semble que la plupart de ces derniers soient morts peu de temps apr&egrave;s avoir &eacute;t&eacute; frapp&eacute;s. La composition selon le sexe et l'&acirc;ge des animaux frapp&eacute;s et perdus &eacute;tait environ la m&ecirc;me que celle des prises, et la proportion des animaux perdus ne variait pas avec la taille du groupe chass&eacute;. On peut remettre en question les affirmations des derni&egrave;res ann&eacute;es concernant une r&eacute;duction du taux de perte caus&eacute;e par l'am&eacute;lioration de la puissance de feu. Durant les 21 ann&eacute;es de l'&eacute;tude, les armes ont subi de grosses am&eacute;liorations, mais celles-ci ont tout simplement fait augmenter la proportion des b&ecirc;tes tu&eacute;es sur le coup, parmi les animaux qui avaient &eacute;t&eacute; frapp&eacute;s et perdus. Les am&eacute;liorations apport&eacute;es aux armes n'ont pas r&eacute;duit la proportion des animaux perdus parmi ceux qui avaient &eacute;t&eacute; frapp&eacute;s.Mots cl&eacute;s: morse, Odobenus rosmarus, Alaska, prises, frapp&eacute;s et perdu

Automatic Text Simplification for People with Intellectual Disabilities

Text simplification (TS) aims to reduce the lexical and structural complexity of a text, while still retaining the semantic meaning. Current automatic TS techniques are limited to either lexical-level applications or manually defining a large amount of rules. In this paper, we propose to simplify text from both level of lexicons and sentences. We conduct preliminary experiments to find that our approach shows promising results

Competition Between Firms that Bundle

Information goods are characterized by high fixed (first-copy) costs, but very low costs for the production of additional copies. Marginal costs of electronically-delivered information goods have been further reduced by the remarkable recent decline in computing and digital communication costs. Most previous research focuses on how a monopolist would perform (and the proper regulation to impose) in such an environment. Achieving dynamic efficiency is difficult because pricing at marginal cost (which is statically efficient) eliminates the incentive to invest in the creation of new content. Recently, the strategy of bundling numerous goods together has been explored in greater detail. Bundling may achieve static efficiency since individuals will face a zero cost on the margin for each item consumed. Yet, dynamic efficiency can be maintained because the producer is able to recover investment costs through bundle sales. This paper analyzes the profitability and welfare properties of bundling in a multi-firm setting. This allows us to explore how incumbents and entrants interact when each firm is selling numerous competing products. Our fundamental conclusion is that even adding only a single firm to this industry with substantial fixed costs and negligible marginal costs will result in much lower prices for consumers, much higher social welfare, and only a moderate reduction in firms' profits regardless of the pricing schemes employed. This outcome is somewhat surprising given that in a standard static two-good Bertrand model, a duopoly would lead to a price war which eliminates the incentive to invest in new content (or to enter the industry in the first place). Although the firms are producing a priori identical items, consumers know that their valuations for the particular items will vary ex post. Thus, no price reduction by one firm can completely eliminate the demand faced by other firms. Although there remains an incentive to invest in new product creation, this incentive is lower than a monopolist would have. As a result, in a dynamic version of this model, the welfare superiority of the duopoly becomes dampened (but not eliminated). Finally, when firms are allowed to sell items both as a bundle and individually, we find that most revenue will be obtained from bundle sales. These results indicate that bundling will persist in a multi-firm setting and suggest that only firms of substantial size will be able to survive in such a market.http://deepblue.lib.umich.edu/bitstream/2027.42/50428/1/bundle-8aug03.pd