This paper examines the impact of government-sponsored venture capitalists (GVCs) on the success of enterprises. Using international enterprise-level data, we identify a surprising non-monotonicity in the effect of GVC on the likelihood of exit via initial public offerings (IPOs) or third party acquisitions. Enterprises that receive funding from both private venture capitalists (PVCs) and GVCs outperform benchmark enterprises financed purely by private venture capitalists if only a moderate fraction of funding comes from GVCs. However, enterprises underperform if a large fraction of funding comes from GVCs. Instrumental variable regressions suggest that endogeneity in the form of unobservable selection effects cannot account for these effects of GVC financing. The underperformance result appears to be largely driven by investments made in times when private venture capital is abundant. The outperformance result applies only to venture capital firms that are supported but not owned outright by governments.

of the 2D structures has approached its limit (< 90%) due to which the energy loss via reflection (2-5%) and thermal radiation heat loss (8-12%) occurs in all the 2D structures.One of the effective strategies for further improving the vapor-generation efficiency is to decrease the surface temperature of the absorber by increasing the surface area within a given projection area. [22] Some unprecedented vapor-generation rates have been reported in various 3D generators, which are all beyond the input solar energy limit. [23][24][25] Here, we have found that bamboos, as a natural hierarchical cellular material, can be excellent 3D solar vapor-generation devices due to their unique structural features. By a simple carbonization progress, the bamboos maintain remarkable mechanical property. Meanwhile, the carbonized bamboo-based evaporator possesses the following advantages: 1) natural hydrophilicity; 2) numerous aligned microchannels acting as highways for rapid water transport; 3) high light absorptance in a broad spectral range; 4) reduced thermal radiation heat loss; 5) lower average temperature than environment; 6) reduced vaporization enthalpy of water confined in the bamboo mesh; 7) remarkable mechanical properties; 8) ability of salt self-cleaning; 9) good scalability and low cost. As a result, a floating carbonized bamboo sample can evaporate water with an extremely high vapor-generation rate of 3.13 kg m −2 h −1 under 1 sun illumination. It also shows superior reusability and stability for solar vapor generation, without any performance degradation after cycling 360 h. The carbonized bamboo shows favorable overall performance compared with other reported solar vapor generators and has attractive applications in desalination as well asindustrial and domestic wastewater abatement. All of these features are elucidated below in detail.Bamboo is the fastest-growing and highest-yielding hierarchical cellular material on the Earth. A typical bamboo reaches maturity within months and ultimate mechanical properties within few years, making it one of the most renewable resources. [26] Figure 1a-c shows the illustration of the design concept for a bamboo-based solar vapor-generation device. Bamboo tubes with desired height were cut from the natural bamboo and were carbonized to make it dark. The carbonized Given the global challenges of water scarcity, solar-driven vapor generation has become a renewed topic as an energy-efficient way for clean water production. Here, it is revealed that bamboo, as a natural hierarchical cellular material, can be an excellent 3D solar vapor-generation device by a simple carbonization progress. A floating carbonized bamboo sample evaporates water with an extremely high vapor-generation rate of 3.13 kg m −2 h −1 under 1 sun illumination. The high evaporation rate is achieved by the unique natural structure of bamboos. The inner wall of bamboo recovers the diffuse light energy and the thermal radiation heat loss from the 3D bamboo bottom, and the outer wall captures energy from the warmer...

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Floquet engineering has the advantage of generating new phases with large topological invariants and many edge states by simple driving protocols. In this work, we propose an approach to obtain Floquet edge states with fourfold degeneracy and even-integer topological characterizations in a spinful Creutz ladder model, which is realizable in current experiments. Putting the ladder under periodic quenches, we found rich Floquet topological phases in the system, which belong to the symmetry class CII. Each of these phases is characterized by a pair of even integer topological invariants (w0, wπ) ∈ 2Z × 2Z, which can take arbitrarily large values with the increase of driving parameters. Under the open boundary condition, we further obtain multiple quartets of topological edge states with quasienergies zero and π in the system. Their numbers are determined by the bulk topological invariants (w0, wπ) due to the bulk-edge correspondence. Finally, we propose a way to dynamically probe the Floquet topological phases in our system by measuring a generalized mean chiral displacement. Our findings thus enrich the family of Floquet topological matter, and put forward the detection of their topological properties. arXiv:1912.09078v1 [cond-mat.mes-hall]

It has long been an aspirational goal to create artificial evaporators that allow omnidirectional energy absorptance, adequate water supply, and fast vapor transportation, replicating the feat of plant transpiration, to solve the global water crisis. This work reveals that magnolia fruits, as a kind of tree‐like living organism, can be outstanding 3D tree‐like evaporators through a simple carbonization process. The arterial pumping, branched diffusion, and confined evaporation are achieved by the “trunk,” “branches,” and “leaves,” respectively, of the mini tree. The mini tree possesses omnidirectional high light absorptance with minimized heat loss and gains energy from the environment. Water confined in the fruit possesses reduced vaporization enthalpy and transports quickly following the Murray's law. A record‐high vapor generation rate of 1.22 kg m−2 h−1 in dark and 3.15 kg m−2 h−1 under 1 sun illumination is achieved under the assistance of the gully‐like furry surface. The “absorption of nutrients” enables the fruit to recover valuable heavy metals as well as to produce clean water from wastewater efficiently. These findings not only reveal the hidden talent of magnolia fruits as cheap materials for vapor generation but also inspire future development of high‐performance, full‐time, and all‐weather vapor generation and water treatment devices.

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