34 research outputs found
For what they are, not for what they bring: The signaling value of gender for financial resource acquisition in academic spin-offs
Due to the novelty of their technology base and the multiple goals pursued by their entrepreneurial teams, academic spin-offs (ASOs) suffer information asymmetries with investors that impair their ability to raise finance. In line with the signaling theory, we expect that observable features of an ASO can mitigate such information asymmetries, especially in conditions of higher uncertainty about the venture. We put forward that a larger share of capital owned by female shareholders adds to such uncertainty due to their outsider condition in academic entrepreneurship and the negative bias of investors against female entrepreneurs.
Through a multi-level Tobit regression on a sample of Italian ASOs, we find that the amount of private investment is negatively associated with the degree of female ownership and positively associated with the investment of the parent university and full professors. The latter two factors moderate the relationship between the degree of female ownership and private investment so that it becomes less negative.
The results provide evidence of the persisting gender gap in entrepreneurial finance and highlight the role of parent universities in closing such a gap
Electroconductive Hydrogel Based on Functional Poly(Ethylenedioxy Thiophene).
Poly(ethylene dioxythiophene) with functional pendant groups bearing double bonds is synthesized and employed for the fabrication of electroactive hydrogels with advantageous characteristics: covalently cross-linked porous 3D scaffolds with notable swelling ratio, appropriate mechanical properties, electroactivity in physiological conditions, and suitability for proliferation and differentiation of C2C12 cells. This is a new approach for the fabrication of conductive engineered constructs
A conducting polymer with enhanced electronic stability applied in cardiac models
Electrically active constructs can have a beneficial effect on electroresponsive tissues, such as the brain, heart, and nervous system. Conducting polymers (CPs) are being considered as components of these constructs because of their intrinsic electroactive and flexible nature. However, their clinical application has been largely hampered by their short operational time due to a decrease in their electronic properties. We show that, by immobilizing the dopant in the conductive scaffold, we can prevent its electric deterioration. We grew polyaniline (PANI) doped with phytic acid on the surface of a chitosan film. The strong chelation between phytic acid and chitosan led to a conductive patch with retained electroactivity, low surface resistivity (35.85 ± 9.40 kilohms per square), and oxidized form after 2 weeks of incubation in physiological medium. Ex vivo experiments revealed that the conductive nature of the patch has an immediate effect on the electrophysiology of the heart. Preliminary in vivo experiments showed that the conductive patch does not induce proarrhythmogenic activities in the heart. Our findings set the foundation for the design of electronically stable CP-based scaffolds. This provides a robust conductive system that could be used at the interface with electroresponsive tissue to better understand the interaction and effect of these materials on the electrophysiology of these tissues
Optimization of Suture-Free Laser-Assisted Vessel Repair by Solder-Doped Electrospun Poly(ε-caprolactone) Scaffold
Poor welding strength constitutes an obstacle in the clinical employment of laser-assisted vascular repair (LAVR) and anastomosis. We therefore investigated the feasibility of using electrospun poly(ε-caprolactone) (PCL) scaffold as reinforcement material in LAVR of medium-sized vessels. In vitro solder-doped scaffold LAVR (ssLAVR) was performed on porcine carotid arteries or abdominal aortas using a 670-nm diode laser, a solder composed of 50% bovine serum albumin and 0.5% methylene blue, and electrospun PCL scaffolds. The correlation between leaking point pressures (LPPs) and arterial diameter, the extent of thermal damage, structural and mechanical alterations of the scaffold following ssLAVR, and the weak point were investigated. A strong negative correlation existed between LPP and vessel diameter, albeit LPP (484 ± 111 mmHg) remained well above pathophysiological pressures. Histological analysis revealed that thermal damage extended into the medial layer with a well-preserved internal elastic lamina and endothelial cells. Laser irradiation of PCL fibers and coagulation of solder material resulted in a strong and stiff scaffold. The weak point of the ssLAVR modality was predominantly characterized by cohesive failure. In conclusion, ssLAVR produced supraphysiological LPPs and limited tissue damage. Despite heat-induced structural/mechanical alterations of the scaffold, PCL is a suitable polymer for weld reinforcement in medium-sized vessel ssLAVR
Interplay between Structure and Dynamics in Chitosan Films Investigated with Solid-State NMR, Dynamic Mechanical Analysis, and X-ray Diffraction
Modern solid-state NMR techniques, combined with X-ray diffraction, revealed the molecular origin of the difference in mechanical properties of self-associated chitosan films. Films cast from acidic aqueous solutions were compared before and after neutralization, and the role of the counterion (acetate vs Cl⁻) was investigated. There is a competition between local structure and long-range order. Hydrogen bonding gives good mechanical strength to neutralized films, which lack long-range organization. The long-range structure is better defined in films cast from acidic solutions in which strong electrostatic interactions cause rotational distortion around the chitosan chains. Plasticization by acetate counterions enhances long-range molecular organization and film flexibility. In contrast, Cl⁻ counterions act as a defect and impair the long-range organization by immobilizing hydration water. Molecular motion and proton exchange are restricted, resulting in brittle films despite the high moisture content
Tissue adhesives for meniscus tear repair: an overview of current advances and prospects for future clinical solutions
La genesi degli spin-off accademici
Il presente lavoro si propone di contribuire alla comprensione del fenomeno degli spin- off estendendo il modello citato all\u2019intera popolazione accademica \u2013 e quindi all\u2019intera gamma delle discipline scientifiche \u2013 con l\u2019obiettivo di individuare le risorse e i fattori motivazionali che spiegano il successo nel processo imprenditoriale. Lo studio empirico ha coinvolto 249 ricercatori di tutti i settori disciplinari afferenti ad un campione di Universit\ue0 italiane ed \ue8 stato condotto con la metodologia della regressione logistica