Jerome Pine - US grants

The aim of this research is to investigate the attributes of small networks of synaptically connected mammalian neurons, formed in microcultures of approximately 10 cells. The development of these networks will be observed, and studies will be made to uncover systematic patterns of connectivity. Subsequently, the effects of chronically imposed patterns of activity on the networks will be studied, as well as the effects of ablation of one or more cells. A system developed in this laboratory will be employed to noninvasively stimulate and record from a microculture so as to determine the synaptic connectivity at a particular time, and then for the same microculture at later times. This system, which is now in use, employs a voltage-sensitive dye for recording and microcircuit culture dishes for stimulation. The culture dishes incorporate an array of 61 extracellular stimulating electrodes under the small area covered by a microculture. With these electrodes, any cell may be stimulated, and the stimulation may be applied chronically while the culture grows. The response to a stimulus of all the cells in a culture can be simultaneously measured with the aid of the dye, which detects changes in cell membrane potentials. The proposed investigation is designed to elucidate basic principles of connectivity and plasticity among the neurons in a network. Initially, simple purely excitatory networks formed by sympathetic neurons will be studied. Afterward, complex cultures of CNS neurons will be examined. Among the experiments will be measurements of the effect on synaptic strength of simultaneous excitation of a pair of pre- and postsynaptic cells, often hypothesized to be a method for network adaptation or learning. Also, experiments will be performed to assess the role of activity when two presynaptic neurons compete at a common postsynaptic cell. These studies, as well as a variety of others, will capitalize on the unique opportunities afforded by the noninvasive system for studying the effects of activity on both cellular and network properties.

The patch clamp electrode has allowed the study of single ion channels in cells in culture. Although the technique has proven to be a powerful tool, as presently used, it has several drawbacks: Only one cell can be studied at a time and cells eventually "die" from exposure to the high salt content which fills the electrode. This research project involves replacing the present pipette-type of patch clamp electrode with one constructed using state-of-the-art microchip technology.

Research experiences for undergraduates will be offered through the Caltech Summer Undergraduate Research Fellowship (SURF) program. The SURF program was started in 1979 and from 1979-1987 621 students participated in research projects. During the 10-week period in the summer the students will participate in technical seminars, roundtable discussions and communications workshops. Ten students will be selected from institutions where research opportunities may be relatively limited including Historically Black Institutions (HBUs). Contacts with the Atlanta University Center, Howard University, Jackson State Univeristy, and Morehouse University have already been established. Undergraduate research experiences will include developing new algorithms or scientific codes and systems software for the hypocube, and working within-house hardware development projects. An award of $39,500 is highly recommended for this meritorious project under the REU programs.

This study will explore alternative testing methods to meet the demands of the hands-on approach to science teaching. Because of the critical importance of early science education, the grantee will work with fifth grade students. The investigative technique will be observation of a hands-on scientific investigation, scored by scientists and science teachers. The investigation will compare four surrogates with this method: (1) computer simulation of a hands-on test, (2) hands-on test with written responses, (3) free response pencil and paper test, and (4) multiple choice test. The data may prove to be of great value in designing cost-effective, practical tests that closely approximate the expensive, logistically difficult, hands-on tests with scientists as observers.

During the past several years, scanning transmission x-ray microscopy has become a reality. The objective of this project is to develop auxiliary equipment, and the required knowledge base, to make this form of microscopy useful for biological studies of whole cultured cells. This work is intended to make it practical to view whole, wet, unstained cells with a spatial resolution ten times finer than that of the light microscope. The cells may be either alive or fixed. This new kind of microscopy has broad significance for researchers in cell biology and neurobiology, particularly those studying the relation of cellular ultrastructure to function. We will develop a specimen system appropriate for imaging live cultured cells. Prototype images will then be obtained to determine the extent to which the natural contrast of unstained specimens reveals their ultrastructure. Immunostaining techniques for whole fixed cells will also be characterized. Studies of radiation damage effects will be made to define the acceptable range of exposures for maintaining both short-term and long-term integrity of live cells and fixed specimens. A modified system optimal for imaging specimens smaller than whole mammalian cells, such as bacteria or myofibrils, will also be developed.

This award provides funds to help with the establishment and initial operation of a microfabrication facility that will produce semi-conductor devices to be used in neuroscience, microelectronics and related areas of microdevice research. The neuroscience devices will be used for both in vitro and in vivo experimentation aimed at the simultaneous monitoring of the activity of an array of nerve cells. Other types of devices to be fabricated include micro-robots, -sensors, -antennas and pumps. An important role of the he facility is expected to be the training of students and advanced investigators who have need of these devices in the techniques used for microfabrication. The remarkable progress in the miniaturization of electronic circuit boards has lead to the realization that a variety of other types of micrometer-sized devices can be made. these include both mechanical and electronic devices. In particular, the ability to fabricate microchip-like multi-well cell culture dishes, where each well is the size of a single cell, has opened up the possibility of simultaneous recording of the activity of each of many interconnected nerve cells growing in culture. This type of experimentation could lead to significant advances in understanding the operation of networks of nerve cells, an area which has, in recent years, been the subject of much theoretical interest. Similar devices, which could be implanted directly in the brain, should allow measurement of the activity of many cells in a single region of the brain. Such experimentation has enormous potential for clarifying our understanding of the functional organization of the brain and of how brain cells integrate and differentiate sensory input.

This project will initiate a hands-on inquiry-based science curriculum in all the elementary school classrooms of the Pasadena Unified School District. The District is urban, multicultural and multiracial. The District's partner, the California Institute of Technology (Caltech), is a preeminent research university. Their combined effort will use a method proven during four years of a very successful partnership between Caltech and one Pasadena pilot school. The initial education for teachers will be presented in small groups each led by a mentor teacher and a volunteer science professional. During these group meetings the teachers will have an opportunity to investigate kit materials which they will use later in their classrooms. The small group will work through the kits in a cooperative learning environment, while the co- leaders emphasize the philosophy and methods of hands-on teaching as well as the scientific subject matter which relates to each kit. During the school year, resource teachers will work with teachers in their classrooms, and meet with them during group meetings. At these sessions teachers will be able to explore other science units and exchange experiences and ideas with their colleagues. The total cost sharing for the project will be 200% of the NSF portion.

The California Institute of Technology will develop and deliver through a collaborative effort by scientists, teacher- educators, and master teachers, a one-semester course for the elementary teacher education program. Future elementary teachers will construct their own science knowledge and work cooperatively in a "hands on" science classroom environment. These prospective teachers will do challenging investigations with sophisticated tools while modeling good science teaching. Simultaneously, the course will provide a solid foundation in fundamental principles of biology, chemistry, physics and earth science. The course will be integrated into the elementary science teacher program.

9453935 Pine This project is designed to promote district-wide change to hands- on inquiry science teaching in the elementary schools of at least fourteen school districts. The model to be supported builds on the experience of the Caltech Precollege Science Initiative (CAPSI), in collaboration with school districts in Pasadena, California, Maui, Hawaii, and Conejo Valley, California. The main features of the model are the initial creation of a fully transformed pilot school, that embodies total teacher support, including science materials, ongoing professional development, and frequent collegial interaction with a mentoring resource teacher. Critical to the entire change effort is the partnership of the school district with practicing scientists and engineers from a university, college, industry, or the community. During this project CAPSI would work with fourteen urban school districts in California to bring about similar change. The total cost sharing of just Caltech and Pasadena will be 10 percent of the NSF portion of the award. ***

9453959 Bower To enable elementary school teachers to teach and assess hands-on, inquiry-based science instruction effectively, this project will create and pilot-test 4 Modules designed to improve and broaden teacher science content knowledge. The proposed modules, to be developed and piloted by teams of teachers from Pasadena, California and scientists from Caltech, will be field tested by school system partnerships in Buffalo, New York, Cleveland, Ohio, Highline, Washington, and Huntsville, Alabama. The modules will have several distinct characteristics. First, each will be based on a science content common to most kit-based curricula. Second, each module will be developed by a collaboration of experienced teachers and scientists. Third, the modules will be designed to be used by teacher-scientist teams leading groups of other teachers in an inquiry-based learning community like that of an exemplary classroom. Materials will initially be published with desktop publishing and then disseminated via existing national networks of school systems engaged in supporting inquiry science instruction at the elementary school level. The cost sharing will be 10% of the NSF funds. ***

This study is a three year effort to examine what students learn in two different kinds of elementary science classrooms: traditional expository, text-oriented instruction compared with hands-on, inquiry-oriented instruction. The latter describes an approach to learning in which students acquire knowledge and understanding of scientific ideas as well as first hand experiential understanding of how scientists study the natural world. The emphasis is on learning by doing and discussing, and the priority is on scientific thinking skills and conceptual understanding. In a second phase, the study examines the teaching associated with high- and low-achieving classrooms for each of the two instructional conditions.

Millions of dollars have gone into supporting hands-on inquiry science reforms over the past several decades. These large-scale efforts, particularly important for less affluent students across the country, are vulnerable however, for they are viewed by some as too expensive or too demanding of teachers. Furthermore, there is little evidence of the relative merits of the two approaches. The nationwide emphasis on accountability, with an intense focus on literacy and math and a bias towards easily tested factual knowledge, pressures schools away from hands-on inquiry science. This study will contribute substantially to our knowledge base on the relationship between elemetary science instruction and student learning, with important implications for practitioners, policy makers and the public.

This study compares 5th grade students' learning in two instructional conditions, with 20 classes in each condition matched for key characteristics. In addition, the study explores connections between student performance and instruction, utilizing data from teacher surveys, interviews, assignments, and classroom observations. Student achievement is assessed with an array of measures, including standardized tests of language arts and math; standardized science knowledge items and a performance task from NAEP or TIMSS; other short science performance tasks; and extended science investigation tasks developed and validated for this research. The study will address long-term, important outcomes such as those called for in Project 2061: deep conceptual understanding, persistence at difficult problems, retention of important knowledge over time, and transfer of investigation strategies to challenging novel situations.

This study is a three year effort to examine what students learn in two different kinds of elementary science classrooms: traditional expository, text-oriented instruction compared with hands-on, inquiry-oriented instruction. The latter describes an approach to learning in which students acquire knowledge and understanding of scientific ideas as well as first hand experiential understanding of how scientists study the natural world. The emphasis is on learning by doing and discussing, and the priority is on scientific thinking skills and conceptual understanding. In a second phase, the study examines the teaching associated with high- and low-achieving classrooms for each of the two instructional conditions.

Millions of dollars have gone into supporting hands-on inquiry science reforms over the past several decades. These large-scale efforts, particularly important for less affluent students across the country, are vulnerable however, for they are viewed by some as too expensive or too demanding of teachers. Furthermore, there is little evidence of the relative merits of the two approaches. The nationwide emphasis on accountability, with an intense focus on literacy and math and a bias towards easily tested factual knowledge, pressures schools away from hands-on inquiry science. This study will contribute substantially to our knowledge base on the relationship between elemetary science instruction and student learning, with important implications for practitioners, policy makers and the public.

This study compares 5th grade students' learning in two instructional conditions, with 20 classes in each condition matched for key characteristics. In addition, the study explores connections between student performance and instruction, utilizing data from teacher surveys, interviews, assignments, and classroom observations. Student achievement is assessed with an array of measures, including standardized tests of language arts and math; standardized science knowledge items and a performance task from NAEP or TIMSS; other short science performance tasks; and extended science investigation tasks developed and validated for this research. The study will address long-term, important outcomes such as those called for in Project 2061: deep conceptual understanding, persistence at difficult problems, retention of important knowledge over time, and transfer of investigation strategies to challenging novel situations.

This 3-year longitudinal project studies how diverse girls' attitudes, perceptions, and experiences in grades 7-12 influence both subtle and explicit choices leading towards or away from a college major in science. Participants come from 4 urban and suburban districts whose students represent a range of economic background and ethnicities. The design would follow two cohorts of students, one from 7th to 10th grade and one from 10th grade into the first year of college. The middle school cohort allows a broad look at student experiences before they formally enter the pipeline, while the high school cohort focuses on those students who are most likely to pursue science and engineering careers. The study includes an annual large-scale survey of the full cohort and an annual in-depth interview with a continuing subset of students. Contextual interviews with selected parents, science teachers, guidance counselors, and others are also included. Both quantitative and qualitative analysis techniques are used.

This project seeks to explore the linkage between school and extracurricular experiences of female students to their decision to pursue a science college major. These variables have been found to be related to the gender gap in achievement and attitudes about science, but a formal linkage between them and girls' decision to pursue a science major has not been established. This research has the potential to identify factors that might facilitate the recruitment of females in science majors.

[unreadable] DESCRIPTION (provided by applicant): [unreadable] The primary goal of this project is to develop a prototype of a silicon-based structure, the "neurochip" which will support the growth and development of cultured neural networks and will greatly enhance the ability of researchers to study them. The structure will be an array of 61 "wells" into which dissociated neurons can be placed, and which will hold each of them in proximity to an extracellular electrode. The wells will allow process outgrowth of axons and dendrites and be closely spaced so as to support synaptic connectivity of the neurons to form a network. The prototype can be scaled up to larger networks, and the fabrication method will be compatible with on-chip CMOS electronics for on-chip processing, control, and wireless communication. [unreadable] [unreadable] The electrodes will provide the capability to stimulate and record from any chosen neurons of the network non-destructively, supporting studies of the network connectivity over time; of patterns of spontaneous activity;, and of activity-dependent effects resulting from stimulation. A second goal of the project is to utilize neurochips to perform an initial series of experiments which will reveal the development of connections, the effects of stimulation on remodeling the network and the creation of "learned" responses. These will provide unique knowledge of network behavior, in detail, beyond what is now possible with available techniques in vivo or in vitro. [unreadable] [unreadable] In addition, neurochip networks have the potential to reveal pharmacological effects relevant to drug design and deveIopment, and also to exhibit the effects on nervous system function of genetic defects. [unreadable] [unreadable]

Project Summary: The aim of this project is to create a system for studying cultured neural networks that will provide a unique new ability for observing how each cell is connected to the others and how that connectivity changes. The cultured neurons will be in cages that are plastic structures which allow process outgrowth but maintain the cell body in close proximity to a recording and stimulating electrode. By stimulating each neuron and recording the responses of all the others, the connectivity of the network will be revealed. The system will have 64 cages in an 8 x 8 array, with 64 dissociated neurons placed in cages using an optical tweezers. The capability to study such networks in detail at the single cell level will be far beyond any that now exists. Recording and stimulation do not damage the neurons, so the connectivity can be observed over a period of weeks, as the network develops. Very sophisticated electronic amplifiers and stimulators on custom large scale integrated circuits will be used, which will provide at low cost the capability of studying multiple caged arrays simultaneously, while they are in an incubator. The studies will provide an opportunity to observe normal network development in detail that has never been possible. In addition, the effects on networks of imposed simulation will be revealed, on time scales of hours to weeks. Pharmacological effects on connectivity will also be observable. Lastly, because they are in cages, cell types can be mixed and placed in known locations, so that type-specific interactions between them as they form networks will be observable. A most interesting example will be to observe the interaction of embryonic-stem-cell derived neurons with networks of normal neurons. As a proof of concept at the end of this study, such experiments will be begun. They will indicate the potential for stem-cell-neuron integration with normal cells in transplants, and also will provide opportunities for studying how to promote that integration.