Abstract: This invention provides populations of mesenchymal cells obtained from pluripotent stem cells by differentiating them ex vivo. Multipotent mesenchymal cells can in turn be differentiated into more specialized cell types such as osteoblasts, with properties that make them suitable for reconstituting musculoskeletal cell function in an individual. The compositions, methods, and techniques described in this disclosure can be used for a variety of commercially important diagnostic, drug screening, and therapeutic applications.

Abstract: This invention provides populations human cells of the cardiomyocyte lineage. The cells are obtained by causing cultures of pluripotent stem cells to differentiate in vitro, and then harvesting cells with certain phenotypic features. Differentiated cells bear cell surface and morphologic markers characteristic of cardiomyocytes, and a proportion of them undergo spontaneous periodic contraction. Highly enriched populations of cardiomyocytes and their replicating precursors can be obtained, suitable for use in a variety of applications, such as drug screening and therapy for cardiac disease.

Abstract: This disclosure provides an improved system for culturing human pluripotent stem cells. Traditionally, pluripotent stem cells are cultured on a layer of feeder cells (such as mouse embryonic fibroblasts) to prevent them from differentiating. In the system described here, the role of feeder cells is replaced by components added to the culture environment that support rapid proliferation without differentiation. Effective features are a suitable support structure for the cells, and an effective medium that can be added fresh to the culture without being preconditioned by another cell type. Culturing human embryonic stem cells in fresh medium according to this invention causes the cells to expand surprisingly rapidly, while retaining the ability to differentiate into cells representing all three embryonic germ layers. This new culture system allows for bulk proliferation of pPS cells for commercial production of important products for use in drug screening and human therapy.

Abstract: Phase shift keying (PSK) or differential phase shift keying (DPSK) used as the coding scheme in a high bit rate, long haul dispersion-managed optical transmission system, in which the signaling format is RZ. The system can combine multiple individual channels with different wavelengths in a WDM or dense wavelength division multiplexed (DWDM) arrangement. Dispersion management can be provided using several techniques, such as by using dispersion managed solitons, quasi-linear transmission or conventional RZ transmission with pre-compensation and post-compensation.

Abstract: An optical performance monitor (OPM), e.g., for use in an optical network. The OPM may be configured to characterize one or more impairments in an optical signal modulated with data. The OPM has an optical autocorrelator configured to sample the autocorrelation function of the optical signal, e.g., using two-photon absorption. Autocorrelation points at various bit delays independently or in combination with average optical power may be used to detect and/or quantify one or more of the following: loss of data modulation, signal contrast, pulse broadening, peak power fluctuations, timing jitter, and deviations from the pseudo-random character of data. In addition, the OPM may be configured to perform Fourier transformation based on the autocorrelation points to obtain corresponding spectral components. The spectral components may be used to detect and/or quantify one or more of chromatic dispersion, polarization mode dispersion, and misalignment of a pulse carver and data modulator.

Abstract: This disclosure provides a system for obtaining genetically altered primate pluripotent stem (pPS) cells. The pPS cells are maintained in an undifferentiated state by culturing on a feeder cell line that has been immortalized and altered with drug resistance genes. Alternatively, the role of the feeder cells is replaced by supporting the culture on an extracellular matrix, and culturing the cells in a conditioned medium. The cells can be genetically altered with a viral vector or DNA/lipid complex, and then selected for successful transfection by drug-resistant phenotype in the transfected cells. The system allows for bulk proliferation of genetically altered pPS cells as important products for use in human therapy or drug screening.

Abstract: This disclosure provides an improved system for culturing human pluripotent stem (pPS) cells in the absence of feeder cells. The role of the feeder cells can be replaced by supporting the culture on an extracellular matrix, and culturing the cells in a conditioned medium. Permanent cell lines are provided that can produce conditioned medium on a commercial scale. Methods have also been discovered to genetically alter pPS cells by introducing the cells with a viral vector or DNA/lipid complex. The system described in this disclosure allows for bulk proliferation of pPS cells for use in studying the biology of pPS cell differentiation, and the production of important products for use in human therapy.

Abstract: This disclosure provides an improved system for culturing human pluripotent stem (pPS) cells in the absence of feeder cells. The role of the feeder cells can be replaced by supporting the culture on an extracellular matrix, and culturing the cells in a conditioned medium. Permanent cell lines are provided that can produce conditioned medium on a commercial scale. Methods have also been discovered to genetically alter pPS cells by introducing the cells with a viral vector or DNA/lipid complex. The system described in this disclosure allows for bulk proliferation of pPS cells for use in studying the biology of pPS cell differentiation, and the production of important products for use in human therapy.

Abstract: This disclosure provides an improved system for culturing human pluripotent stem (pPS) cells in the absence of feeder cells. The role of the feeder cells can be replaced by supporting the culture on an extracellular matrix, and culturing the cells in a conditioned medium. Permanent cell lines are provided that can produce conditioned medium on a commercial scale. Methods have also been discovered to genetically alter pPS cells by introducing the cells with a viral vector or DNA/lipid complex. The system described in this disclosure allows for bulk proliferation of pPS cells for use in studying the biology of pPS cell differentiation, and the production of important products for use in human therapy.

Abstract: This invention provides media that support the growth of primate pluripotent stem cells in feeder-free culture, and cell lines useful for producing such media and for other purposes, such as use as a primary feeder layer. Conventionally, it has been necessary to grow pluripotent embryonic cells on feeder layers of primary embryonic fibroblasts, in order to prevent them from differentiating. It has now been discovered that standard culture media conditioned by special cell lines can be used to support proliferation of pluripotent stem cells while inhibiting differentiation in an environment free of feeder cells. This invention includes mesenchymal and fibroblast-like cell lines obtained from embryonic tissue or differentiated from embryonic stem cells. Methods for deriving such cell lines, processing media, and growing stem cells using the feeder cells or conditioned media are described and illustrated in this disclosure.

Abstract: An electrooptic probe for measuring the voltage at regions of an ultra fast device under test includes a standard gallium arsenide substrate that includes on a front surface a film of LT GaAs whose surface includes a conductive stripe that includes first and second portions separated by a gap, the first portion for contacting the region under test, and the second portion for connection to a measuring instrument. The probe is irradiated with a pulsed beam of light, advantageously from a mode-locked femtosecond laser focused at the gap in the stripe and of appropriate two photons, for making conducting by two-photon absorption the region of the film underlying the gap. Preferably the beam irradiates the back surface of the probe to pass through its substrate to reach the gap. Alternatively the beam can irradiate the back surface of the device under test to reach the gap.

Abstract: This invention provides media that support the growth of primate pluripotent stem cells in feeder-free culture, and cell lines useful for producing such media and other purposes. Conventionally, it has been necessary to grow pluripotent embryonic cells on feeder layers of primary embryonic fibroblasts, in order to prevent them from differentiating. It has now been discovered that standard culture media conditioned by special cell lines can be used to support proliferation of pluripotent stem cells while inhibiting differentiation in an environment free of feeder cells. This invention includes mesenchymal and fibroblast-like cell lines obtained from embryonic tissue or differentiated from embryonic stem cells. Methods for deriving such cell lines, processing media, and growing stem cells using the conditioned media are described and illustrated in this disclosure.

Abstract: Semiconductor devices are imaged using two-photon absorption. The method is similar to conventional optical beam induced imaging except that the light beams used have frequencies (photon energies) insufficient to excite electrons across the semiconductor bandgap. Rather the instantaneous intensity of the lower frequency light is increased, as by using a pulsed laser source, so that electron transitions occur by two-photon absorption predominately in the localized region where the beam is focused. The result is minimal absorption during passage through the substrate and maximal absorption in the component-rich active layer where the beam is focused. This enhances imaging of fine-detail semiconductor devices. Specifically, the quadratic dependence of free carrier generation on the excitation intensity both enhances the resolution and provides a three-dimensional sectioning capability.

Abstract: In a time-division-multiplex system, a relatively high-rate optical signal stream comprising multiple interleaved signal sequences is applied to one end of an elongated waveguide that includes multiple photodetectors disposed along the longitudinal extent of the waveguide. Probe pulses at a relatively low rate are applied to the other end of the waveguide in a synchronized fashion to cause two-photon non-linear absorption in successive respective photodetectors as each propagating probe pulse overlaps successive different signals of each sequence. In that way, electrical output signals are provided from each photodetector at the relatively low probe-pulse rate.