Third ERTS Symposium: Abstracts

Abstracts are provided for the 112 papers presented at the Earth Resources Program Symposium held at Washington, D.C., 10-14 December, 1973

Simple dynamics of automorphisms

AbstractLet F be a free group of rank two or more. Aut(F) acts on the Gromov boundary ∂F as a group of homeomorphisms. The maximal subgroups G<Aut(F) containing Inn(F) that act as discrete convergence groups on ∂F are finite extensions of Inn(F)

Third Earth Resources Technology Satellite Symposium. Volume 3: Discipline summary reports

Presentations at the conference covered the following disciplines: (1) agriculture, forestry, and range resources; (2) land use and mapping; (3) mineral resources, geological structure, and landform surveys; (4) water resources; (5) marine resources; (6) environment surveys; and (7) interpretation techniques

Third Earth Resources Technology Satellite Symposium. Volume 2: Summary of results

Summaries are provided of significant results taken from presentations at the symposium along with some typical examples of the applications of ERTS-1 data for solving resources management problems at the national, state, and local levels

“If They Could See Me Now!”: College Students Reflect on Their Experiences as Special Education Students in the K-12 System*

The current study examined the experiences of six students with learning disabilities in a four-year public, liberal arts college and discusses the meaning they attributed to their previous identification as special education students while in the K-12 system. Data was gathered through a semi-structured interview, questionnaire, and a sentence stem structure. A qualitative approach was used and results were analyzed using principles of content analysis. Themes emerging as noteworthy were: (a) the effect on relationships with peers, (b) lack of developmental knowledge by school support staff, (c) family support, and (d) the challenges of upholding expectations

From indexed grammars to generating functions

We extend the Chomsky/Sch\"utzenberger method of computing the growth series of an unambiguous context-free language to the larger class of indexed languages. We illustrate the technique with numerous examples.Comment: 23 pages, 3 figure

Ideal boundaries of pseudo-Anosov flows and uniform convergence groups, with connections and applications to large scale geometry

Given a general pseudo-Anosov flow in a three manifold, the orbit space of the lifted flow to the universal cover is homeomorphic to an open disk. We compactify this orbit space with an ideal circle boundary. If there are no perfect fits between stable and unstable leaves and the flow is not topologically conjugate to a suspension Anosov flow, we then show: The ideal circle of the orbit space has a natural quotient space which is a sphere and is a dynamical systems ideal boundary for a compactification of the universal cover of the manifold. The main result is that the fundamental group acts on the flow ideal boundary as a uniform convergence group. Using a theorem of Bowditch, this yields a proof that the fundamental group of the manifold is Gromov hyperbolic and it shows that the action of the fundamental group on the flow ideal boundary is conjugate to the action on the Gromov ideal boundary. This implies that pseudo-Anosov flows without perfect fits are quasigeodesic flows and we show that the stable/unstable foliations of these flows are quasi-isometric. Finally we apply these results to foliations: if a foliation is R-covered or with one sided branching in an atoroidal three manifold then the results above imply that the leaves of the foliation in the universal cover extend continuously to the sphere at infinity.Comment: 69 pages. Major revision, more explanations and simplified some simplified proofs. Detailed explanations of scalloped regions, parabolic points and perfect fit horoballs. 22 figures (3 new figures

Complexes of Groups and Boundaries

Given a complex of groups over a finite simplicial complex in the sense of Haefliger, we give conditions under which it is possible to build an EZ-structure in the sense of Farrell-Lafont for its fundamental group out of such structures for its local groups. As an application, we prove a combination theorem that yields a procedure for getting hyperbolic groups as fundamental groups of simple complexes of hyperbolic groups. The construction provides a description of the Gromov boundary of such groups.Comment: 60 pages, 4 figure

Gastric Bypass Promotes More Lipid Mobilization Than a Similar Weight Loss Induced by Low-Calorie Diet

Background. Recently, we found large reductions in visceral and subcutaneous fat one month after gastric bypass (GBP), without any change in liver fat content. Purpose. Firstly to characterize weight loss-induced lipid mobilization after one month with preoperative low-calorie diet (LCD) and a subsequent month following GBP, and secondly, to discuss the observations with reference to our previous published findings after GBP intervention alone. Methods. 15 morbidly obese women were studied prior to LCD, at GBP, and one month after GBP. Effects on metabolism were measured by magnetic resonance techniques and blood tests. Results. Body weight was similarly reduced after both months (mean: −8.0 kg, n = 13). Relative body fat changes were smaller after LCD than after GBP (−7.1 ± 3.6% versus −10 ± 3.2%, P = .029, n = 13). Liver fat fell during the LCD month (−41%, P = .001, n = 13) but was unaltered one month after GBP (+12%). Conclusion. Gastric bypass seems to cause a greater lipid mobilization than a comparable LCD-induced weight loss. One may speculate that GBP-altered gastrointestinal signalling sensitizes adipose tissue to lipolysis, promoting the changes observed

Biologic validation of diagnoses of depression

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/24517/1/0000796.pd