More Bang For Your Buck: Quorum-Sensing Capabilities Improve the Efficacy of Suicidal Altruism

Within the context of evolution, an altruistic act that benefits the receiving individual at the expense of the acting individual is a puzzling phenomenon. An extreme form of altruism can be found in colicinogenic E. coli. These suicidal altruists explode, releasing colicins that kill unrelated individuals, which are not colicin resistant. By committing suicide, the altruist makes it more likely that its kin will have less competition. The benefits of this strategy rely on the number of competitors and kin nearby. If the organism explodes at an inopportune time, the suicidal act may not harm any competitors. Communication could enable organisms to act altruistically when environmental conditions suggest that that strategy would be most beneficial. Quorum sensing is a form of communication in which bacteria produce a protein and gauge the amount of that protein around them. Quorum sensing is one means by which bacteria sense the biotic factors around them and determine when to produce products, such as antibiotics, that influence competition. Suicidal altruists could use quorum sensing to determine when exploding is most beneficial, but it is challenging to study the selective forces at work in microbes. To address these challenges, we use digital evolution (a form of experimental evolution that uses self-replicating computer programs as organisms) to investigate the effects of enabling altruistic organisms to communicate via quorum sensing. We found that quorum-sensing altruists killed a greater number of competitors per explosion, winning competitions against non-communicative altruists. These findings indicate that quorum sensing could increase the beneficial effect of altruism and the suite of conditions under which it will evolve.Comment: 8 pages, 8 figures, ALIFE '14 conferenc

Farm-Level Evaluation of Agricultural and Environmental Policies with an Integrated Modeling System

Concern is growing throughout the United States about environmental and health risks associated with the use of agricultural chemicals. In response to these concerns, public policies designed to alter farming practices and the use of agricultural chemicals are being proposed and implemented. In addition, existing U.S. agricultural policies directed at price stabilization and income support are being reviewed for interdependencies with environmental measures. This paper provides a farm-level analysis of the interrelationships between the current U.S. commodity program for corn and selected environmentally motivated policies for controlling the use of corn rootworm insecticides. An integrated modeling system is employed that includes economic and biological components. The farm modeled is for opportunities for coordinating agricultural commodity and environmental policies. Policy adjustments are identified that can reduce corn rootworm insecticide use, improving the quality of the environment and limiting health risk, while only modestly affecting certainly equivalent farm income

Flexibility and the Integration of Commodity and Environmental Policies

Environmental and health risk concerns associated with the use of agricultural chemicals in the United States are increasing. In response, public policies designed to alter farming practices and the use of agricultural chemicals are being proposed and implemented. In addition, agricultural price stabilization and income support policies are being reviewed for environmental implications. This paper provides a farm-level analysis of the interrelationships between the current U.S. commodity program for corn and selected policies for controlling the use of corn rootworm insecticides. The farm modeled is for Chickasaw County, Iowa. Results show significant opportunities for coordinating agricultural commodity and environmental policies. Corn rootworm insecticide use can be reduced with only modest effects

Replication of Primary HIV-1 Isolates Is Inhibited in PM1 Cells Expressing sCD4-KDEL

AbstractExpression of a soluble CD4 molecule (sCD4-KDEL) containing a specific retention signal for the endoplasmic reticulum was shown previously to block propagation of the HIV-1MNprototype strain in a transformed T cell line. However, the virus present in HIV-1-infected individuals is more closely represented by primary HIV-1 isolates which, unlike the HIV-1MNstrain, have not been adapted to growth in cell lines. To determine if sCD4-KDEL could block replication of primary isolates we used the PM1 cell line that has been shown to propagate primary isolates without adaptation. Here we show that the replication of four primary HIV-1 isolates was strongly inhibited in PM1 cells that expressed sCD4-KDEL under control of the HIV-1 LTR. Infection with primary HIV-1 isolates induced sCD4-KDEL expression driven by the LTR, HIV-1 spread was dramatically reduced, and reverse transcriptase activity in the cell culture supernatants was greatly diminished. sCD4-KDEL, therefore, represents a potent inhibitor of HIV-1 replication for gene therapy-based approaches for the treatment of AIDS

Valuation of Closely-Held Stock for Federal Tax Purposes: Approach to an Objective Method

The present double-standard approach to the valuation problem discriminates against owners of closely-held stock, that is, corporate shares which have no public market. The disparity of treatment is traceable to the unfortunate fact that, whereas actual sales or bona fide bid and asked prices govern the valuation for federal tax purposes of listed stocks and of unlisted stocks which are dealt in through brokers or have a market, the criteria employed in valuing closely-held stock are predominantly subjective. This makes a paradise for experts but they seldom agree and few, if any, of their assumptions and conclusions are anything more than unverified, and not always wholly disinterested, hunches. As a consequence, disagreement between taxpayer and revenue agent is frequent and the process of resolving disagreement is long and costly and the event uncertain. In short, the whole merry-go-round of valuing closely-held stock is wasteful and unfair. This paper and the study it reports are addressed to the possibility of improving the situation by making a fresh approach to the valuation of closely-held stock

The Powerful Potential of Relationships and Community Writing

The following essay is a collective reflection in which the authors revisit the themes they raise in the edited volume Unsustainable, ask new questions, and suggest, again, that long-term sustainability might not be the most appropriate goal for every university-community partnership. Still, relationships, with all their variability, remain the lifeblood of community writing work. Just as the Conference on Community Writing (CCW) was a welcome opportunity to reconnect with old friends and learn new names, our programs are built on the strength of the relationships we build in the community and on our campuses

Labor and Management Relations: Historical Perspectives and Current Trends

Capstone paper from 2015 spring MPA program. Instructed by Allen Zagoren.Over the last 125 years, labor unions and management in the United States have had working relationships that have ranged from positive to co-existence to adversarial. In recent decades, declines in union membership, politically charged legislation seeking to limit union influence, and pressures on management to maintain profits in a global economy have introduced further strain on labor and management relations. In this paper we will examine the factors that impact labor and management relationships on a local level and what can be done to improve them. To provide a bigger context, the history of legislation and economic factors that have influenced labor and management relationships throughout their existence in this country will be explored. Additionally, interviews of labor and management leaders revealed generational differences, complacency, and lack of communication can negatively impact labor and management relationships. Solutions to these problems will be offered and include utilizing a “Problem- Solving, Relationship-Building” (PS/RB) approach. Although hard metrics for this approach are difficult to define, it has been used successfully on both an organizational level as well as on a regional level. Finally, we will describe the resources available to not only begin this approach with labor and management, but to sustain the effort and the benefits it offers

Bilateral Comparison of Elbow Ulnar Collateral Ligament Thickness in Division I Baseball Athletes

It has been established the mechanics of throwing a baseball contributes to ulnar collateral ligament (UCL) injury because of the repetitive valgus stress on the anterior band of the UCL, as it is the primary stabilizer of valgus stress in the elbow. This repetitive stress has been shown to cause adaptations in tensile properties leading to damage or failure of the UCL. Previous research has shown that ultrasound imaging may have the ability to detect changes in the UCL before the onset of symptoms in pitchers. PURPOSE: This study was performed to compare bilateral UCL thickness in Division I baseball players. METHODS: 22 Division I baseball players from the same university participated in this study. The players were separated into two groups based on position: pitchers (n=11; 190.9 ± 7.8 cm; 92.3 ± 11.2 kg) and position players (n=11; 184.6 ± 7.0 cm; 85.9 ± 10.8 kg). Ultrasound imaging was captured bilaterally on the players’ elbows using B-mode ultrasonography (LOGIQ, GE Healthcare). Players were tested seated in a reclined position with the arm resting on a plinth, shoulder abducted 90o, elbow extended 150o, and with forearm in a supinated position. The midpoint thickness of the UCL was measured in millimeters using ImageJ (National Institute of Health). The difference between throwing arm and non-throwing arm UCL thickness was calculated as ‘UCL Dif’. A two-way mixed factor ANOVA (position [pitcher vs position player] x arm [throwing arm and non-throwing arm]) was used to analyse UCL thickness. RESULTS:[BD1] There was no position x arm interaction (p=0.735); however, there were significant main effects for position (p = 0.003) and arm (p ≤ 0.001). When collapsed by position, UCL thickness was significantly greater in the throwing arm compared to the non-throwing arm (0.621 ± 0.008 mm vs. 0.581 ± 0.008 mm). When collapsed across arms, pitchers had significantly greater throwing arm UCL thickness compared to position players (0.618 ± 0.008 vs. 0.518 ± 0.008). CONCLUSION: The UCL thickness in pitchers’ throwing elbow was greater compared to position players. The greater UCL thickness in the throwing arm appears to be an adaptive change to the repetitive stress during a pitch. We believe the known relationships between UCL thickness, player position, and arm dominance can be best explained by positional demands and throwing style

Variation in reversal learning by three generalist mesocarnivores

Urbanization imposes novel challenges for wildlife, but also provides new opportunities for exploitation. Generalist species are commonly found in urban habitats, but the cognitive mechanisms facilitating their successful behavioral adaptations and exploitations are largely under-investigated. Cognitive flexibility is thought to enable generalists to be more plastic in their behavior, thereby increasing their adaptability to a variety of environments, including urban habitats. Yet direct measures of cognitive flexibility across urban wildlife are lacking. We used a classic reversal-learning paradigm to investigate the cognitive flexibility of three generalist mesocarnivores commonly found in urban habitats: striped skunks (Mephitis mephitis), raccoons (Procyon lotor), and coyotes (Canis latrans). We developed an automated device and testing protocol that allowed us to administer tests of reversal learning in captivity without extensive training or experimenter involvement. Although most subjects were able to rapidly form and reverse learned associations, we found moderate variation in performance and behavior during trials. Most notably, we observed heightened neophobia and a lack of habituation expressed by coyotes. We discuss the implications of such differences among generalists with regard to urban adaptation and we identify goals for future research. This study is an important step in investigating the relationships between cognition, generalism, and urban adaptation