6,522 research outputs found
The topology of deformation spaces of Kleinian groups
Let M be a compact, hyperbolizable 3-manifold with nonempty incompressible
boundary and let AH(\pi_1(M)) denote the space of (conjugacy classes of)
discrete faithful representations of \pi_1(M) into PSL 2 (C). The components of
the interior MP(\pi_1(M)) of AH(\pi_1(M)) (as a subset of the appropriate
representation variety) are enumerated by the space A(M) of marked
homeomorphism types of oriented, compact, irreducible 3-manifolds homotopy
equivalent to M. In this paper, we give a topological enumeration of the
components of the closure of MP(\pi_1(M)) and hence a conjectural topological
enumeration of the components of AH(\pi_1(M)). We do so by characterizing
exactly which changes of marked homeomorphism type can occur in the algebraic
limit of a sequence of isomorphic freely indecomposable Kleinian groups. We use
this enumeration to exhibit manifolds M for which AH(\pi_1(M)) has infinitely
many components.Comment: 49 pages, published versio
Effects of Nitrogen Fertilization on Monoterpenes of Jack Pine Seedlings and Weight Gain of Jack Pine Budworm (Lepidoptera: Tortricidae)
Nine-month old jack pine (Pinus banksiana) seedlings were grown in a greenhouse under four nitrogen fertilization regimes. Levels of total nitrogen and five monoterpenes in new foliage were measured. Fertilization resulted in four significantly different levels of foliar nitrogen; means ranged from 1.8-4.5 percent dry weight. Contrary to predictions of resource availability theory, seedlings grown under the highest fertilization regime had higher foliar monoterpene levels than seedlings in the other treatments. Newly molted, sixth-instar female jack pine budworm (Choristoneura pinus pinus [Lepidoptera: Tortricidae]) larvae were allowed to feed for four days on new foliage of the seedlings. Larvae that fed on low-nitrogen seedling gained less weight and process more vegetation than did larvae on high- nitrogen seedlings. Larval weight gain was positively related to foliar nitrogen
Exhibits and Demonstrations for Junior Farm Management Clubs
The State Fair Board offers attractive cash premiums for exhibits made by members of Fa.rm Ma1:1agement Clubs. These exhibits consist of two sketches of the member\u27s farm showing location and arrangement of fields and buildings and a copy of their account book with entries complete to August 15 or later. One sketch should picture the farm as it is now and the other as it would appear after any changes had been made. These sketches should be on cardboard 11 by 22 inches or 22 by 28 inches in size. Additional account books will be furnished by the Extension Service to members desiring to exhibit at the State Fair. These books will be numbered so that members need not put their names on their exhibits
Cybershopping Levels The Playing Field In Global Retailing
Today\u27s business environment has an ever-changing landscape. The environment is no longer just local, regional, or national. It is a global environment. The most successful businesses will have to be able to meet the needs of its customers before its competitors. Many people do not like huge stores and crowded aisles. Also, the element of customer service seems to be vanishing. This has led to customer dissatisfaction. Customers are increasingly looking for a new format in which they can buy their goods. They have increasingly turned to the Internet. The future of the Internet looks bright. Retailers are making their home pages user friendly and consumers are gaining more confidence and becoming more computer literate
The Murky Waters of Sex Differences in Post-stroke Cognitive Impairment
A new study indicates that although men and women are equally likely to experience cognitive impairment after acute ischaemic stroke, there are sex differences in particular cognitive domains. Whether these differences are directly linked to biological sex is uncertain, as many factors, including age and pre-stroke factors, could contribute to cognitive outcomes
The role of data & program code archives in the future of economic research
This essay examines the role of data and program-code archives in making economic research "replicable." Replication of published results is recognized as an essential part of the scientific method. Yet, historically, both the "demand for" and "supply of" replicable results in economics has been minimal. "Respect for the scientific method" is not sufficient to motivate either economists or editors of professional journals to ensure the replicability of published results. We enumerate the costs and benefits of mandatory data and code archives, and argue that the benefits far exceed the costs. Progress has been made since the gloomy assessment of Dewald, Thursby and Anderson some twenty years ago in the American Economic Review, but much remains to be done before empirical economics ceases to be a "dismal science" when judged by the replicability of its published results.Econometrics ; Research
Determination and Reduction of Large Diffeomorphisms
Within the Hamiltonian formulation of diffeomorphism invariant theories we
address the problem of how to determine and how to reduce diffeomorphisms
outside the identity component.Comment: 4 pages, Latex, macro espcrc2.sty. Contribution to the proceedings of
the second conference on Constrained Dynamics and Quantum Gravity, Santa
Margherita, Italy, 17-21 September 1996. To appear in Nucl. Phys. B Supp
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