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Sepehr Ghazinoory Zahra Hashemi 《The Journal of High Technology Management Research》2021,32(1):100394
Tax incentives and direct funding are two different public support instruments used to facilitate the formation and growth of firms. Limited empirical evidence has compared the effectiveness of two different policies and their interactions for firms. In this paper, we investigate the main and interaction effects of these interventions on high-tech firms. Since large and small firms innovate in different ways, we compare the use of both incentives by Iranian high-tech SMEs and large firms through a factorial design technique. This paper presents significant differences both across instruments and across firm size. Results show that for SMEs, tax exemption has a significant effect on R&D investment, and funding has a significant effect on R&D investment, R&D employees, and new products. However, there aren't any interaction effects between instruments. For large firms, funding is an effective instrument for R&D investment. Also, there is an interaction effect between tax incentives and direct funding on new products. These findings indicate that funding is a more effective instrument than tax exemption, especially for SMEs, but suggest some changes in supporting policies of high-tech firms in Iran. 相似文献
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Drawing on data from a study of learning, race, and equity in an urban high school organized around specialized learning academies, we examine the ways in which the design, framing, construction, and organization of learning spaces deeply influences the types of access to rigorous learning that students experience. We draw on the notion of racialized learning pathways to examine access to science, technology, engineering, and mathematics (STEM) learning spaces and the ways in which decisions about engaging these learning settings are bound up in notions of race, racial identity, gender, and belonging. We also take up the questions of how researchers and educators can intentionally design for positive racialization toward more inclusive school organization and classrooms. This article contributes to understanding of (a) how learning and identity development are mediated by broader processes of racialization tied to schooling organization and access structures and (b) how racial and gender inequities in STEM can be both reproduced and contested in large urban schools serving racially and socioeconomically diverse students. We contribute to the literature on equity and access in STEM by attending to the racialization processes that we argue are always at work in urban schools, particularly so in schools that are organized into pathways demarcated along racialized lines. 相似文献
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kihana miraya ross Na’ilah Suad Nasir Jarvis R. Givens Maxine McKinney de Royston Sepehr Vakil Tia C. Madkins 《Equity & Excellence in Education》2016,49(1):85-99
ABSTRACTThis article examines the teaching philosophies of Black male teachers of Black male students in manhood development classes in a district-wide program in Oakland, California. Drawing on observations and instructor interview data, we explore the teachers’ histories, teaching philosophies, and the trajectory of their racial-educational understandings. We utilize Gramsci's (1971) theory of the organic intellectual, Mills’ (1997) and Leonardo's (2013) theories of the subperson and substudent, and Dumas’ (2014) notion of Black suffering to theorize the ways that race comes into play in the teaching of African American male students. We find that racialization and re-humanization are key to instructors’ teaching, and we identify two key aspects of their teaching philosophies: (1) Humanization/Love and (2) Reciprocity. 相似文献
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We present a microfluidic technique that generates asymmetric giant unilamellar vesicles (GUVs) in the size range of 2–14 μm. In our method, we (i) create water-in-oil emulsions as the precursors to build synthetic vesicles, (ii) deflect the emulsions across two oil streams containing different phospholipids at high throughput to establish an asymmetric architecture in the lipid bilayer membranes, and (iii) direct the water-in-oil emulsions across the oil–water interface of an oscillating oil jet in a co-flowing confined geometry to encapsulate the inner aqueous phase inside a lipid bilayer and complete the fabrication of GUVs. In the first step, we utilize a flow-focusing geometry with precisely controlled pneumatic pressures to form monodisperse water-in-oil emulsions. We observed different regimes in forming water-in-oil multiphase flows by changing the applied pressures and discovered a hysteretic behavior in jet breakup and droplet generation. In the second step of GUV fabrication, an oil stream containing phospholipids carries the emulsions into a separation region where we steer the emulsions across two parallel oil streams using active dielectrophoretic and pinched-flow fractionation separations. We explore the effect of applied DC voltage magnitude and carrier oil stream flow rate on the separation efficiency. We develop an image processing code that measures the degree of mixing between the two oil streams as the water-in-oil emulsions travel across them under dielectrophoretic steering to find the ideal operational conditions. Finally, we utilize an oscillating co-flowing jet to complete the formation of asymmetric giant unilamellar vesicles and transfer them to an aqueous phase. We investigate the effect of flow rates on properties of the co-flowing jet oscillating in the whipping mode (i.e., wavelength and amplitude) and define the phase diagram for the oil-in-water jet. Assays used to probe the lipid bilayer membrane of fabricated GUVs showed that membranes were unilamellar, minimal residual oil remained trapped between the two lipid leaflets, and 83% asymmetry was achieved across the lipid bilayers of GUVs. 相似文献
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