Southern Baja California, Mexico: Implication of Mantle and
Crustal Sources during the Opening of an Asthenospheric Window
Mathieu Benoit, Aifredo Aguillón-Robles, Thierry Calmus, René C. Maury, Hervé
Bellon, Joseph Cotton, Jacques Bourgois, and Francois Michaid - Unite Mixte de
Recherche (UMR) 6538, Domaines Oceaniques, institut Universitaire Europëen de
laMer (1UEM), Université de Bretagne Occidentale, Place Nicolas Copernic,
2928 Plouzané, France
Manuscript received July 17, 2001; accepted January 31 2002.
ABSTRACT
Five main petrologic and geochemical groups can be identified among the Middle to
Late Miocene lavas from the western part of southern Baja California: (1) caic-alkaline
and K-rich andesites emplaced between 15.5 and 11.7 Ma; (2) adakites and (3)
associated niobium-rich basalts erupted between 11.7 and 8.5 Ma in the Santa Clara
volcanic field, Vizcaino Peninsula; (4)10.6—9.2 Ma tholeiitic basalts and basaltic
andesites that form large tabular plateaus near San Ignacio; and (5) magnesian and
basaltic andesites of adakitic affinity whose emplacement started at 11.7 Ma south of
San Ignacio and between 9.7 and 8.8 Ma near La Purisima. These lavas, although
spatially and temporally related, display very different geochemical signatures. Their
trace elements and isotopic characteristics suggest that three different magma sources
were involved in their genesis. Partial melts of subducting altered oceanic crust
produced the adakites when erupted directly at the surface. These magmas were
eventually trapped in the mantle wedge where they reacted with ultramafic lithologies.
Such slab-melt-metasomatized mantle could then melt to produce niobium-rich basalts
or magnesian andesitea, depending on the pressure that controlled the stability of garnet
into the mantle wedge. The melting of fiuidmetasomatized mantle wedge led to the
emplacement of andesites. In southern Baja California, the opening of a slab window
following active ridge subduction resulted in the additional contribution of partial melts
from the suboceanic mantle uprising through the tear in the slab. This process might be
responsible for the occurrence of tholeiitic basalts and basaltic andesites near San
Ignacio. The studied association can be considered as a modem analog of high-thermalregime Archean subductions.
Version 2.0
Grant Number: 1R29GM054909-01
P1 Name:
WOERPEL, KEITH A.
Abstract
Project Title: SILACYCLOPROPANES--BUILDING BLOCKS FOR ORGANIC
SYNTHESIS
Abstract: DESCRIPTION: The principal investigator notes that although the fundamental
chemistry of si1acycl~propanes has been explored, these compounds have not been utilized in
organic synthesis. He reports that preliminary data suggest that these strained-ring silanes are
useful building blocks for the construction of polyoxygenated organic compounds. It is stated
that the silacyclopropane acts as a masked 1,3-diol, and new carbon-carbon bonds are
formed with high stereoselectivity (greater than 98 percent). The principal investigator indicates
that the proposal details methods for the construction of propionate (and dipropionate) units
terminated by an acetyaldebyde unit and that this architectural feature, which can be difficult to
install if it possesses anti stereochemistry, is shared by many therapeutically Important
compounds, such as amphotericin B and nystatin Al, representatives of the polyene macrolide
antibiotics. It is noted that these compounds are the most effective drugs for combating systemic
fungal infections, which occur in immunocompromised patients undergoing cancer
chemotherapy and transplants, as well as AIDS patients and that new methods which facilitate
the preparation of the polyene macrolides and their analogs for conducting structure-activity
studies are important to the progress of the health sciences. The principal investigator states that
in particular, the following will be demonstrated: (1) the insertion of formarnides into
silacyclopropanes will lead to new methods for the synthesis of polyoxygenated compounds,
culminating in the total synthesis of stegobiol, the sex pheromone of a pest responsible for the
destruction of stored grain; (2) metal-catalyzed reactions such as silylene transfer reactions will
provide new syntheses of silacyclopropanes, and metal-catalyzed insertion reactions will
generate useful poiyoi substructures; (3) silacyclopropanes with aromatic substituents on the
silicon atom will be investigated to determine their reactivity; and (4) the generality of a
modified oxidation of silanes to alcohols will be determined.
Thesaurus Terms;
chemical structure function, chemical synthesis, cyclopropane, method development, organic
chemical, oxygen compound, silane
alcohol, chemical transfer reaction, formamide, metal complex, oxidation, oxidation
Abstract
Nederland Middle Senior High School qualifies for funding from the Senate Bill
96-197, Excellence in Learning Through Technology as a rural school.
The mission statement for Nederland Middle Senior School is :
In our school all teachers, staff, parents, and patrons will work
together as a caring, trusting team sharing our unique talents and
resources to provide an environment for each individual to be valued,
to grow, and to achieve success.
The moneys this school is requesting will allow access to technology to all
populations equitable to other schools in the district. With request to the Boulder
Valley School District Science Content Standards, Nederland Middle Senior
High School is highly motivated to reform their Science Department.
Recently a bond issue was passed to build an addition to and remodel our
building. This shows community support for improvement and a move forward
with the support of a technology plan. This bond increased the availability of
technology in our building for Math and Writing. Funding from the Excellence
in Learning Through Technology Grant would greatly enhance our ability to
move towards meeting the Science Content Standards in our district.
The focus of this proposal is to provide technology within our Science
Department. Teachers will attend training sessions to become proficient with the
technology and learn how to integrate this technology into their classroom.
These funds will be used to procure equipment and tools for learning for our
science laboratory, training for teachers, curriculum for students and provide
analysis of student progress.
The funding from this grant would enable Nederland Middle Senior High School
to further the mission of the school and of Boulder Valley School District by
enhancing the ability of the Science Department to address all learning styles and
provide more academic rigor.
CDA—960 1602
Bergeron, R. Daniel University of New Hampshire
Academic Research Infrastructure: Laboratory for Advanced Communications
Systems
This Academic Research Infrastructure award supports the acquisition of high
speed networking equipment including wireless and wired networking
infrastructure and switches. The research projects supported by this
instrumentation include research on local electromagnetic field
characterization, testing tools for wireless local area data communications
standards, model-based network diagnosis, implementation and evaluation of
algorithms for ATM Quality of Service policies, and the design,
implementation and evaluation of data parallel I/O using high speed networks
and heterogeneous workstations.
Rotator Cuff Tendinosis in an Animal Model: Role of Extrinsic and Overuse
Factors
Louis J. Soslowsky1, Stavros Thomopoulos, 1 Adil Esmail, 1 Colleen L. Flanagan, 1
Joseph P. lannotti, 1 J. David Williamson III, 1 and James E. Carpenter2
1
McKay Orthopaedic Research Laboratory, University of Pennsylvania, Philadelphia, PA
Orthopaedic Research Laboratories, University of Michigan, Ann Arbor, MI
2
(Received 15 February 2002; accepted 22 July 2002)
The rat shoulder animal model has been used previously to study the role of intrinsic injury
(modeled as an acute insult to the tendon), extrinsic injury (modeled as external subacromial
impingement), and overuse factors on rotator cuff tendinosis. These studies demonstrated that it
is possible to produce rotator cuff tendinosis with any one of these factors in isolation. The
current study uses the rat shoulder model to study the roles of extrinsic compression, overuse,
and overuse in combination with extrinsic compression, on the development of rotator cuff
tendinosis. The results of this study demonstrate that the injury created by overuse plus extrinsic
compression is greater than the injuries created by overuse or extrinsic compression alone,
particularly when important biomechanical variables are considered. While ineffective in causing
a change in supraspinatus tendon properties in animals with normal cage activity, extrinsic
compression had a significant and dramatic effect when it was combined with overuse activity.
Without an additional factor, such as overhead activity, the extrinsic compression alone may be
insufficient to cause tendinosis. The results of the present study support the role of multiple
factors in the etiology of some rotator cuff injuries.
©2002 Biomedical Eng!neering Society.
SGER: Discrete Event Simulation of Self-Assembly Kinetics
Abstract - EIA-0320595 Russell Schwartz Carnegie Mellon University
Project Summary: Discrete Event Simulation of Self-Assembly Kinetics The goal of this project
is to develop a novel computational tool for simulating generalized self-assembly systems. Selfassembly systems consist of many small components, or subunits, that spontaneously arrange
themselves into larger structures under appropriate conditions. Among the many medically
important self assembly systems are viral protein shells, or capsids, which form protective coats
around the genetic material of viruses; amyloids, fibrous agglomerations of proteins that are
implicated in Alzheimer.s disease, Huntington.s disease, and the prion diseases; and irregular
protein aggregates. For all of these systems, the process of assembly is only partially understood.
In addition, self-assembly has attracted recent interest as a means of constructing man-made
devices and materials on the nanometer scale. Due to the small size, speed, and complexity of
many self-assembly processes, they have proven difficulty to analyze experimentally. Simulation
approaches have therefore emerged as a crucial avenue for gaining insight into the self-assembly
process. This project seeks to build on the prior work in the area by creating a model of the selfassembly process sufficiently versatile to capture a wide variety of se1f-assembly systems, yet
fast enough to handle realistic simulation sizes in a reasonable time. The basic methodology will
involve combining techniques developed in prior modeling work on this problem with a
computational method that has not previously been used for self-assembly simulation. The
simulator will use a model of self-assembly dynamics based largely on the prior local rules
dynamics. model, which provided a versatile representation of high-level self- assembly behavior
in terms of low-level subunit interactions. It will be efficiently implemented using a
computational data structure called a .discrete event priority queue,. which will allow the
simulator to step between changes in discrete state (such as subunits binding to one another)
without the need for explicit integration over all time steps. The result will be faster simulation
of a highly general self-assembly model than was possible with prior methods. The simulator
will be implemented in Java to facilitate ease of development, extensibility, and portability.
Implementation will be conducted through distinct phases devoted to developing an object model
(which specifies how pieces of computer code interact with one another), coding and testing a
prototype simulator, and finalizing an optimized and well documented release-quality version.
The end result will be both a stand-alone simulation tool and a set of computational classes
available for extension and use in other programs. This work will require innovation primarily in
mathematical models of self-assembly processes and in algorithms for their efficient simulation
by a discrete event queue methodology. Further innovation will be needed in the integration of
existing knowledge from such areas as biophysics, algorithms, software engineering, and user
interface design to produce a versatile, easy-to-use graphical simulation tool. The project can be
expected to yield several benefits. Its impact will be primarily on the field of self-assembly, by
providing a general tool that can be used by researchers throughout the field for modeling known
systems across size and time scales, developing computational prototypes of novel systems, and
experimenting with interventions in both. It will also provide new methods and experience to the
general field of biophysical simulation through the development of a novel simulation
methodology, its implementation in a computational simulator, and optimization of algorithms
for this problem. The cross-disciplinary nature of the project will enhance its impact by
providing for the computational community new variations on problems to be found in
biophysical systems and providing for the biophysics community new computational techniques
that can be brought to bear on other problems. The work will also have educational value by
providing interdisciplinary research experience to students, including two undergraduates, and by
providing a simulator that can be used as both a research and a teaching tool.