Detaching embedded points

We show that if $D \subset \mathbb P^N$ is obtained from a codimension two local complete intersection $C$ by adding embedded points of multiplicity $\leq 3$, then $D$ is a flat limit of $C$ and isolated points. As applications, we determine the irreducible components of Hilbert schemes of space curves with high arithmetic genus, show the smoothness of the Hilbert component whose general member is a plane curve union a point in $\mathbb P^3$, and construct a Hilbert component whose general member has an embedded point.Comment: 16 pages, amsart style. New examples added to show that hypotheses of main theorem are necessary, showing sharpness of resul

A study of tagging methods for the sea cucumber Cucumaria frondosa in the waters off Maine

The sea cucumber fishery in waters off Maine is developing and has recently experienced great increases in landings, corresponding to expanding export markets. Between 1994 and 1996, reported landings ranged from one to three million pounds (Fig. 1). In 1999, reported landings were over eight million pounds and rose to over nine million in 2000 (Feindel1). Like other developing fisheries, we have little information about the biology and ecology of the sea cucumber off Maine, limited data on the fishery, and little knowledge about the key life history processes that characterize its population dynamics. Therefore, we have a limited understanding of the current status of the resource and the impacts the fishery may have on the stock

Experimental evaluation into novel, low cost, modular PEMFC stack

Attribution-NonCommercial-NoDerivs 3.0 Unported (CC BY-NC-ND 3.0)The Polymer Electrolyte Membrane Fuel Cell (PEMFC), despite being regarded as an ideal replacement to the internal combustion engine, is still not an economically attractive pri-mover due to a number of key challenges that have yet to be fully resolved; some of which include degradation to cell components resulting in inadequate lifetimes, specialised and costly manufacturing processes and poor gravimetric/volumetric energy densities. This paper presents a novel stack concept which removes the conventional bi polar plate (BPP), a component that is responsible for up to 80% of total stack weight and 90+% of stack volume in some designs. The removal of said component not only improves the volumetric and gravimetric energy density of the PEMFC stack but drastically reduces the cost of the stack by removing all costly manufacturing processes associated with PEMFC component machining while the functionality of the traditional BPP is still retained by the unique stack design. The stack architecture is first presented and then the characterisation of the PEMFC is shown over a wide range of operating scenarios. The experimental studies suggest that the performance of the new design is comparable to that of traditional stacks but at significantly less cost price.Final Published versio

Pathways from caring and engaging adults to youth vocational identity: the mediational roles of career search self-efficacy and goal capacity

This study examines the role played by access to caring and engaging adults, career search self-efficacy (CSSE), and goal capacity in the development of youth vocational identity. The study used a bootstrapping approach to analyze data, collected from a survey of 1,579 youths enrolled in 14 U.S. high schools, to test a hypothesized serial multiple mediation model. Results indicate both direct and multiple indirect pathways from adults influences to the youth vocational identity. Two specific pathways of influence were found through CSSE and goal capacity respectively. Additionally, a serial multiple mediation effect was found whereby CSSE and goal capacity collectively mediated the relationship. This indicates that greater access to caring and engaging adults contributes to higher CSSE, which accounts for a higher level of goal capacity, and eventually leads to the better vocational identity in youth. These findings establish notable implications for practices that are discussed in closing.First author draf

MARKET EMERGENCE AND THE RISE AND FALL OF BACKYARD HOG PRODUCTION IN CHINA

This paper first identifies an interesting pattern in farm household livestock production in many developing countries: an inverted-U shape relationship between household livestock production and the levels of economic development (or farm household income). Using backyard hog production as a case study, the paper documents the ways in which trends in market development appear to correspond with observed trends in household hog production. After providing theoretical explanation of linkage between market development and household hog production, the paper econometrically estimates the effects of market development on household hog production. The results indicate that grain and labor market development can explain a significant portion of the rise and fall in China's backyard hog sector over the past two decades.Community/Rural/Urban Development, Consumer/Household Economics,

A Variational Assimilation Method for Satellite and Conventional Data: a Revised Basic Model 2B

A variational objective analysis technique that modifies observations of temperature, height, and wind on the cyclone scale to satisfy the five 'primitive' model forecast equations is presented. This analysis method overcomes all of the problems that hindered previous versions, such as over-determination, time consistency, solution method, and constraint decoupling. A preliminary evaluation of the method shows that it converges rapidly, the divergent part of the wind is strongly coupled in the solution, fields of height and temperature are well-preserved, and derivative quantities such as vorticity and divergence are improved. Problem areas are systematic increases in the horizontal velocity components, and large magnitudes of the local tendencies of the horizontal velocity components. The preliminary evaluation makes note of these problems but detailed evaluations required to determine the origin of these problems await future research

Farm Technology and Technical Efficiency: Evidence from Four Regions in China

In this paper we fit stochastic frontier production functions to data for Chinese farms grouped into each of four regionshousehold farm; labor migration; land fragmentation; stochastic production frontier; technical efficiency