2,964 research outputs found
Entrepreneurial Spawning: Public Corporations and the Genesis of New Ventures, 1986-1999
This paper examines the factors that lead to the creation of venture capital backed start-ups, a process we term entrepreneurial spawning.' We contrast two alternative views of the spawning process. In one view, employees of established firms are trained and conditioned to be entrepreneurs by being exposed to the entrepreneurial process and by working in a network of entrepreneurs and venture capitalists. Alternatively, individuals become entrepreneurs because the large bureaucratic companies for which they work are reluctant to fund their entrepreneurial ideas. Controlling for a firm's size, patent portfolio and industry, we find that the most prolific spawning firms were public companies located in Silicon Valley and Massachusetts that were themselves once venture capital backed. Less diversified firms are also more likely to spawn new firms. Spawning levels for these firms rise as their sales growth declines. Firms based in Silicon Valley and Massachusetts and originally backed by venture capitalists are more likely to spawn firms only peripherally related to their core businesses. Overall, these findings appear to be more consistent with the view that entrepreneurial learning and networks are important factors in the creation of venture capital backed firms.
4,40-Dimethyl-2,20-bipyridinium dichloride
In the title compound, C12H14N22+·2Cl-, the 4,4'-dimethyl-2,2'-bipyridinium cation is essentially planar (r.m.s. deviation for all non-H atoms = 0.004 Å) and is located on a crystallographic inversion centre. The cations and chloride anions lie in planes parallel to (111) and are connected by N-H...Cl and C-H...Cl hydrogen bonds. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.003 Å; R factor = 0.036; wR factor = 0.080; data-to-parameter ratio = 14.7
Shaping Laguerre-Gaussian laser modes with binary gratings using a Digital Micromirror Device
Laguerre-Gaussian (LG) beams are used in many research fields, such as
microscopy, laser cavity modes and optical tweezing. We develop a holographic
method of generating pure LG modes (amplitude and phase) with a binary
amplitude-only Digital Micromirror Device (DMD), as an alternative to the
commonly used phase-only Spatial Light Modulator. The advantages of such a DMD
include very high frame rates, low cost and high damage thresholds. We show
that the propagating shaped beams are self-similar and their phase fronts are
of helical shape as demanded. We estimate the purity of the resultant beams to
be above 94%
A Genetic Locus Regulates the Expression of Tissue-Specific mRNAs from Multiple Transcription Units
129 GIX- mice, unlike animals of the congeneic partner strain GIX+, do not express significant amounts of the retroviral antigens gp70 and p30. Evidence is presented indicating that the GIX phenotype is specified by a distinct regulatory gene acting on multiple transcription units to control the levels of accumulation of specific mRNA species. The steady-state levels of retroviral-homologous mRNA from the tissues of GIX+ and GIX- mice were examined by blot hybridization using as probes DNA fragments from cloned murine leukemia viruses. RNA potentially encoding viral antigens was reduced or absent in GIX- mice, even though no differences in integrated viral genomes were detected between these congeneic strains by DNA blotting. Tissue-specific patterns of accumulation of these RNA species were detected in brain, epididymis, liver, spleen, and thymus, and several distinct RNA species were found to be coordinately regulated with the GIX phenotype. Measurements of RNA synthesis suggest a major role for transcriptional control in the regulation of some retroviral messages
Skill vs. Luck in Entrepreneurship and Venture Capital: Evidence from Serial Entrepreneurs
This paper argues that a large component of success in entrepreneurship and venture capital can be attributed to skill. We show that entrepreneurs with a track record of success are more likely to succeed than first time entrepreneurs and those who have previously failed. Funding by more experienced venture capital firms enhances the chance of success, but only for entrepreneurs without a successful track record. Similarly, more experienced venture capitalists are able to identify and invest in first time entrepreneurs who are more likely to become serial entrepreneurs. Investments by venture capitalists in successful serial entrepreneurs generate higher returns for their venture capital investors. This finding provides further support for the role of skill in both entrepreneurship and venture capital.
Venture Capital Investment Cycles: The Impact of Public Markets
It is well documented that the venture capital industry is highly volatile and that much of this volatility is associated with shifting valuations and activity in public equity markets. This paper examines how changes in public market signals affected venture capital investing between 1975 and 1998. We find that venture capitalists with the most industry experience increase their investments the most when public market signals become more favorable. Their reaction to an increase is greater than the reaction of venture capital organizations with relatively little industry experience and those with considerable experience but in other industries. The increase in investment rates does not affect the success of these transactions adversely to a significant extent. These findings are consistent with the view that venture capitalists rationally respond to attractive investment opportunities signaled by public market shifts.
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