SOME IMPLICATIONS OF THE TWO-CONSTRAINT JOINT RECREATIONAL CHOICE DEMAND MODEL

This paper explores the implications of applying a two-constraint joint recreational demand framework to estimate the demand for recreation at an Alaskan sportfishery. The demand for total days on-site and total trips per season are jointly estimated and used to parametrically define average on-site time and obtain consumer's surplus values.Resource /Energy Economics and Policy,

Valuing a Beach Day with a Repeated Nested Logit Model of Participation, Site Choice, and Stochastic Time Value

Beach recreation values are often needed by policy-makers and resource managers to efficiently manage coastal resources, especially in popular coastal areas like Southern California. This article presents welfare values derived from random utility maximization-based recreation demand models that explain an individual’s decisions about whether or not to visit a beach and which beach to visit. The models utilize labor market decisions to reveal each individual’s opportunity cost of recreation time. The value of having access to the beach in San Diego County is estimated to be between $21 and$23 per day.Recreation demand, repeated nested logit, labor supply, opportunity cost of leisure, time, beach recreation., Demand and Price Analysis, Environmental Economics and Policy, Institutional and Behavioral Economics, Q26, J22, Q51.,

Yeast Polarity: Negative Feedback Shifts the Focus

A new study of Cdc42p polarization in yeast suggests that the actin cytoskeleton can destabilize the polarity axis, causing Cdc42p foci to wander aimlessly around the cell cortex

ESTIMATING THE OPPORTUNITY COST OF RECREATION TIME IN AN INTEGRABLE 2-CONSTRAINT COUNT DEMAND MODEL

How researchers treat the opportunity cost of time substantially influences recreation demand parameter and welfare estimates. This paper presents a utility-theoretic and implementable approach, estimating the shadow value of time jointly with recreation demands for coastal activities, using a generalization of the semilog demand system in a two-constraint model.Consumer/Household Economics, Demand and Price Analysis,

The inhibition of neutrophil antibacterial activity by ultra-high molecular weight polyethylene particles.

Following infection, bacterial killing by polymorphonuclear leukocytes (neutrophils) is the main host defense against bacteria. Our hypothesis is that particles of ultra-high molecular weight polyethylene (UHMWP) may impair local neutrophil function and consequently reduce neutrophil bacterial killing. To determine how the in vitro phagocytic-bactericidal activity of neutrophils was affected by exposure to wear particles, tests were run comparing the effects of different particle composition, and different concentrations and sizes of UHMWP particles. There was a significant correlation between the number of particles and the decrease in neutrophil bactericidal activity (p<0.01), and the greatest effect was obtained with a concentration of 10(7) UHMWP/ml. There was a significant decrease in neutrophil bactericidal activity by incubation with particles of 0.1-5 microm (p<0.01), but not with larger size. The results suggest that neutrophil functional defects triggered by the presence of UHMWP particles may potentially contribute to the susceptibility of loose implants to bacterial infections

Sustainable EV Market Incentives: Lessons Learned from European Feebates for a Zero Emissions Future

Strong policies are needed to accelerate the zero-emission vehicle (ZEV) transition so that it occurs at a pace in line with international climate goals. The purchase price of new vehicles tends to be the variable that most affects consumer decisions. With urgency for a ZEV transition, fiscal pressure for governments can be high as rebates for consumers and incentives supporting manufacturers in the switch to ZEV technologies will be needed for a mass-market transition. Fees on high-polluting vehicles—and rebates on clean ones—have become an effective and increasingly common strategy in European countries. The feebate mechanism can raise the necessary capital for financing a ZEV transition in combination with other regulatory mechanisms. This paper reviews and assesses feebate design types, issues, and implementation strategies in France, Germany, Italy, Sweden, and the United Kingdom. These examples show that feebates can be designed in a variety of ways to meet unique policy objectives and that periodic adjustments are helpful in achieving goals. Among twelve design considerations for an effective feebate, the authors find that: (1) focusing on a single fee parameter, such as CO2 emissions, can be a simple yet effective mechanism; (2) a continuous functional form for the fee and a stepwise rebate are likely to be most effective in driving EV adoption; and (3) pure feebates, where fee revenue funds EV incentives by program design, provide certainty for manufacturers, regulators, and consumers. View the NCST Project Webpag

Sustainable EV Market Incentives: Equitable Revenue-Neutral Incentives for Zero-emission Vehicles in the United States

The United States (US), under the Biden Administration, has set a goal of reaching a 50% sales share for zero-emission vehicles by 2030. The administration is pursuing a combination of aggressive fuel economy and greenhouse gas performance standards along with tax credits for consumers who purchase electric vehicles (EVs). Given the anticipated high costs of the EV transition and limited public funds, policy mechanisms that generate extra-budgetary funding are enticing. Feebates—where a fee charged on some purchases is used to offer a rebate for others—can serve as a self-sustaining tool. Feebates have been attempted at the state and federal level in the US but did not pass legislatures due to a lack of political support for levying a fee on internal combustion engine (ICE) vehicles. However, as governments face increasing fiscal constraints, there is greater support for self- funding EV incentive programs. Feebate policies can provide certainty for both producers and consumers to facilitate a steady transition to sustainable transportation. This paper assesses the potential utility of feebates for shaping the US light-duty vehicle market. The analysis demonstrates that: (1) revenue-neutral incentive systems are possible and (2) revenue-neutrality can be achieved with relatively low fees on ICE vehicles to support economic equity among buyers. From an industry perspective, market certainty can be created by incorporating fuel economy targets into a fee schedule as pivot points and allocating fees to finance rebates. This would likely influence industry investment decisions in ways that increase EV production and model availability. View the NCST Project Webpag

An algorithm for collapsing sign alternating sequences of real numbers

AbstractA table with two rows and n columns may be thought of as two vectors with n components. The distance between the two rows then corresponds to the norm of the difference between the rows. We examine the problem of how to collapse the adjacent columns of the table while keeping the norm of the difference as large as possible. First a stepwise algorithm is given which achieves this end with respect to the norm of the vector of differences. After proving the optimality of the stepwise solution we extend the result to the norm which arises from minimizing the number of persons misclassified. The same algorithm suffices

Polo-Like Kinase 2-Dependent Phosphorylation of NPM/B23 on Serine 4 Triggers Centriole Duplication

Duplication of the centrosome is well controlled during faithful cell division while deregulation of this process leads to supernumary centrosomes, chromosome missegregation and aneuploidy, a hallmark of many cancer cells. We previously reported that Polo-like kinase 2 (Plk2) is activated near the G1/S phase transition, and regulates the reproduction of centrosomes. In search for Plk2 interacting proteins we have identified NPM/B23 (Nucleophosmin) as a novel Plk2 binding partner. We find that Plk2 and NPM/B23 interact in vitro in a Polo-box dependent manner. An association between both proteins was also observed in vivo. Moreover, we show that Plk2 phosphorylates NPM/B23 on serine 4 in vivo in S-phase. Notably, expression of a non-phosphorylatable NPM/B23 S4A mutant interferes with centriole reduplication in S-phase arrested cells and leads to a dilution of centriole numbers in unperturbed U2OS cells. The corresponding phospho-mimicking mutants have the opposite effect and their expression leads to the accumulation of centrioles. These findings suggest that NPM/B23 is a direct target of Plk2 in the regulation of centriole duplication and that phosphorylation on serine 4 can trigger this process