El objetivo principal del presente estudio de investigación consiste en ofrecer un análisis sistemático del régimen administrativo sancionador que recae sobre grandes plataformas digitales, en cuanto ...superintermediadores con poder de alterar los necesarios equilibrios, ad intra y ad extra, de mercados e, incluso, completos ecosistemas digitales surgidos al amparo de las nuevas tecnologías de la información y de la comunicación. Para ello, se ahondará en la transformación que imprime la sociedad de la información desde una perspectiva legal y cómo, para dar respuesta a los múltiples desafíos e interrogantes que propicia esta nueva realidad digital, nace una normativa que regula específicamente este tipo de plataformas: la Digital Services Act y, sobre todo, en lo que aquí interesa, la Digital Markets Act. Estas regulaciones son un instrumento para el fomento de mercados disputables y leales.
The controlled release of salicylic acid (SA), a key phytohormone, was mediated by using a novel decanethiol gatekeeper system grafted onto mesoporous silica nanoparticles (MSNs). The decanethiol was ...conjugated only to the external surfaces of the MSNs through glutathione (GSH)-cleavable disulfide linkages and the introduction of a process to assemble gatekeepers only on the outer surface so that the mesopore area can be maintained for high cargo loading. Raman and nitrogen sorption isotherm analyses confirmed the successful linkage of decanethiol to the surface of MSNs. The in vitro release of SA from decanethiol gated MSNs indicated that the release rate of SA in an environment with a certain amount of GSH was significantly higher than that without GSH. More importantly, in planta experiments showed the release of SA from decanethiol gated MSNs by GSH induced sustained expression of the plant defense gene PR-1 up to 7 days after introduction, while free SA caused an early peak in PR-1 expression which steadily decreased after 3 days. This study demonstrates the redox-responsive release of a phytohormone in vitro and also indicates the potential use of MSNs in planta as a controlled agrochemical delivery system.
The introduction of stimuli-responsive cargo release capabilities on self-propelled micro- and nanomotors holds enormous potential in a number of applications in the biomedical field. Herein, we ...report the preparation of mesoporous silica nanoparticles gated with pH-responsive supramolecular nanovalves and equipped with urease enzymes which act as chemical engines to power the nanomotors. The nanoparticles are loaded with different cargo molecules (Ru(bpy)3Cl2 (bpy = 2,2′-bipyridine) or doxorubicin), grafted with benzimidazole groups on the outer surface, and capped by the formation of inclusion complexes between benzimidazole and cyclodextrin-modified urease. The nanomotor exhibits enhanced Brownian motion in the presence of urea. Moreover, no cargo is released at neutral pH, even in the presence of the biofuel urea, due to the blockage of the pores by the bulky benzimidazole:cyclodextrin-urease caps. Cargo delivery is only triggered on-command at acidic pH due to the protonation of benzimidazole groups, the dethreading of the supramolecular nanovalves, and the subsequent uncapping of the nanoparticles. Studies with HeLa cells indicate that the presence of biofuel urea enhances nanoparticle internalization and both Ru(bpy)3Cl2 or doxorubicin intracellular release due to the acidity of lysosomal compartments. Gated enzyme-powered nanomotors shown here display some of the requirements for ideal drug delivery carriers such as the capacity to self-propel and the ability to “sense” the environment and deliver the payload on demand in response to predefined stimuli.
Colloquium talks at prestigious universities both create and reflect academic researchers’ reputations. Gender disparities in colloquium talks can arise through a variety of mechanisms. The current ...study examines gender differences in colloquium speakers at 50 prestigious US colleges and universities in 2013–2014. Using archival data, we analyzed 3,652 talks in six academic disciplines. Men were more likely than women to be colloquium speakers even after controlling for the gender and rank of the available speakers. Eliminating alternative explanations (e.g., women declining invitations more often than men), our follow-up data revealed that female and male faculty at top universities reported no differences in the extent to which they (i) valued and (ii) turned down speaking engagements. Additional data revealed that the presence of women as colloquium chairs (and potentially on colloquium committees) increased the likelihood of women appearing as colloquium speakers. Our data suggest that those who invite and schedule speakers serve as gender gatekeepers with the power to create or reduce gender differences in academic reputations.
In this article, we focus on ways in which 'internal migration industries' shape the housing location of refugees in cities. Based on empirical studies in Halle, Schwerin, Berlin, Stuttgart and ...Dresden, we bring two issues together. First, we show how a specific financialised accumulation model of renting out privatised public housing stock to disadvantaged parts of the population has emerged that increasingly targets migrant tenants. With the growing immigration of refugees to Germany since 2015, this model has intensified. Second, we discuss how access to housing is formed by informal agents. While housing is almost inaccessible for households on social welfare, the situation is even worse for refugees. This situation has given rise to a new 'shadow economy' for housing that offers services with dubious quality for excessive fees. Bringing these two issues together, we argue that housing provision to refugees has become a new business opportunity. This has given rise to a broad variety of 'internal migration industries' that provide the housing infrastructure, but also control access to housing. This not only results in new opportunities for profit extraction, but actively shapes new patterns of segregation and the concentration of refugees in particular types of disadvantaged neighbourhoods.
This study provides a snapshot of the hierarchy-of-influences model in the new media environment through examining the effects of audience web metrics on editors. Surveying 318 gatekeepers, the study ...found that audience metrics influence editors in gatekeeping. Editors’ likelihood to monitor web metrics is affected by their journalism training. Gatekeepers who attach the importance of high readership to economic benefits are more likely to have different news decisions based on web metrics. The study suggests a revision of the hierarchy-of-influences model with more emphasis being placed on the role of the audience.
The aim of this study is to build a theoretical framework to understand how gendered networking practices produce or counter inequalities in organizations. We introduce a practice approach combined ...with a feminist perspective in organization network studies. The notions of gender and networking as social practices allow better insights into what people say and do in networks, and the ways that networking produces or counters gender inequalities. We draw on empirical material about professorial appointments in Dutch academia and analyse the accounts of gatekeepers illuminating their networking practices. The accounts show which networking practices gatekeepers routinely use in recruitment and how these networking practices are intertwined with gender practices. We use the notion of mobilizing masculinities to understand the self‐evident identification of men gatekeepers with men in their networks, and to understand how both men and women gatekeepers prefer the male candidates that resemble the proven masculine success model. Furthermore, this study provides the first empirical insights in mobilizing femininities in which women search for and support women candidates. We show how the gender practice of mobilizing femininities is a more precarious and marked practice than mobilizing masculinities. Mobilizing femininities in networking is intended to counter gender inequalities, but is only partially successful. Through constructions of ‘who you can trust’ or ‘who is a risk’, gatekeepers exercise the power of inclusion and exclusion and contribute to the persistence of structural gender inequalities.
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•Individuals’ role in absorbing external knowledge is ill-defined and rarely measured.•Assimilation is key for R&D staff to realize opportunities for open innovation.•Assimilation ...involves making a marriage of materials and broadcasting it to colleagues.•Gatekeepers achieve innovation through synergy between external search and assimilation.•Shepherds achieve innovation through synergy between assimilation and championing.
Through interviews and a large-scale survey of R&D scientists and engineers, this paper explores individuals’ attempts to absorb external knowledge, focusing on their efforts to identify and assimilate external knowledge and promote its utilization. Extant research does not explicitly address whether individuals should better specialize in certain absorption efforts or rather work as generalists dedicated to a range of efforts. We suggest that assimilation efforts increase the value of individuals’ efforts at external search and at promoting the utilization of external knowledge, which culminates in two main absorption roles that can help individuals achieve greater innovation performance. We argue that gatekeepers who combine external search with assimilation effort help to achieve innovation by contributing to building potential absorptive capacity, while shepherds who combine assimilation with utilization effort aid innovation by building realized absorptive capacity. We find support for these predictions and discuss the implications for research and managerial practice in open innovation.
Gatekeepers have been studied as knowledge mediators for companies, institutions, and regions. This paper contributes to the discussion of the effects of the presence of gatekeepers on regional ...inventive performance. Specifically, the article tests whether there is a causal effect of the presence of gatekeepers on the number of patents per capita, on high-tech patents, and on the degree of technological diversification or specialization. Based on a rich Brazilian microdatabase, we use the propensity matching score to infer causal effects without incurring bias stemming from selection. The main results show a causal effect running from the presence of gatekeepers to a higher number of patents per capita, to a higher number of high-tech patents and to a higher technological specialization level.
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Construction of dual gatekeepers-functionalized mesoporous organic silica nanoparticles (MONs) with both physical and chemical mechanisms for modulated drug delivery properties ...provides one solution to the extracellular stability vs. intracellular high therapeutic efficiency of MONs that hold great potential for clinical translations.
We reported herein facile construction of diselenium-bridged MONs decorated with dual gatekeepers, i.e., azobenzene (Azo)/polydopamine (PDA) for both physical and chemical modulated drug delivery properties. Specifically, Azo can act as a physical barrier to block DOX in the mesoporous structure of MONs for extracellular safe encapsulation. The PDA outer corona serves not only as a chemical barrier with acidic pH-modulated permeability for double insurance of minimized DOX leakage in the extracellular blood circulation but also for inducing a PTT effect for synergistic PTT and chemotherapy of breast cancer.
An optimized formulation, DOX@(MONs-Azo3)@PDA resulted in approximately 1.5 and 2.4 fold lower IC50 values than DOX@(MONs-Azo3) and (MONs-Azo3)@PDA controls in MCF-7 cells, respectively, and further mediated complete tumor eradication in 4T1 tumor-bearing BALB/c mice with insignificant systematic toxicity due to the synergistic PTT and chemotherapy with enhanced therapeutic efficiency.
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