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Unique among metazoan repressive histone methyltransferases, G9a and GLP, which target histone 3 lysine 9 (H3K9), require dimerization for productive H3K9 mono (me1)- and dimethylation (me2) in vivo. Intriguingly, even though each enzyme can independently methylate H3K9, the predominant active form in vivo is a heterodimer of G9a and GLP. How dimerization influences the central H3K9 methyl binding (“reading”) and deposition (“writing”) activity of G9a and GLP, and why heterodimerization is essential in vivo remains opaque. Here, we examine the H3K9me “reading” and “writing” activities of defined, recombinantly produced homo- and heterodimers of G9a and GLP. We find that both reading and writing are significantly enhanced in the heterodimer. Compared to the homodimers, the heterodimer has higher recognition of H3K9me2, and a striking ~ 10-fold increased kcat for nucleosomal substrates under multiple turnover conditions, which is not evident on histone tail peptide substrates. This however is not encoded by altered nucleosome affinity, which is dominated by the G9a protomer and comparable across the homo- and heterodimer. Our results indicate that heterodimerization may be required to relieve autoinhibition of H3K9me reading and chromatin methylation evident in G9a and GLP homodimers. Relieving this inhibition may be particularly important in early differentiation when large tracts of H3K9me2 are deposited by G9a-GLP, which may require a more active form of the enzyme.

Digital advances and consumers' buying behaviors disrupt the retail industry demanding more seamless experiences during their buys. In response, retailers are adopting an omnichannel retailing strategy (OCR), which is the integration of retailers' physical and digital channels. However, OCR is a premature concept, and there is still a lack of research in the subject, which limits the guidance for its practical application. Thus, there is still the need to understand the subject. For OCR managers, it is necessary to understand the main challenges in order to orchestrate it better. Therefore, this research undertakes the task to study the factors that challenge OCR's orchestration, from a managerial perspective. The research departs from primary and secondary data that was later categorized according to its main factor and incorporated into an existing analytical framework of OCR. The findings indicate three main challenge groups that could hinder an orchestrator's impact on the organization. Those are particular capabilities for the OCR, the integration of channels, and technology and data leverage. Los avances digitales y los comportamientos de compra de los consumidores perturban la industria minorista demandando experiencias más fluidas durante sus compras. En respuesta, las empresas están adoptando una estrategia de omnicanal (OCR – omnichannel retailing), que es la integración de los canales físicos y digitales de los minoristas. Sin embargo, OCR es un concepto prematuro, y todavía hay una falta de investigación en el tema, lo que limita la guía para su aplicación práctica. Por lo tanto, todavía existe la necesidad de comprender el tema. Para los gerentes de OCR es importante comprender los principales desafíos para una mejor organización. Por lo tanto, esta investigación emprende la tarea de estudiar los factores que desafían la orquestación del omnicanal de minoristas (OCR), desde una perspectiva gerencial. La investigación parte de datos primarios y secundarios que luego se categorizaron según su factor principal y se incorporaron a un marco analítico existente de OCR. Los resultados indican tres grupos principales de desafíos que podrían dificultar el impacto de un orquestador en la organización. Esos son las capacidades particulares para el OCR, la integración de canales, y el apalancamiento de tecnología y datos.

Final project for AREC489N: Economics of Local Agriculture: Food Hubs (Spring 2016). University of Maryland, College Park., The Howard County Office of Community Sustainability is seeking food hub-based solutions that connect small and mid-sized farmers in Howard County with restaurants and retailers to expand the market for locally produced agricultural products. Under the supervision of instructor Philip Gottwals, the University of Maryland’s PALS-affiliated AREC 489N team studied successes and failures of organizations that have undertaken similar projects to determine the most appropriate and feasible solutions to the issues raised. A review of public data quickly revealed that Howard County's agricultural sector is both small and highly diversified. As such it offers both opportunities for, and challenges to, the creation of a food hub. Vegetable production, for example, is limited to 110 acres of production with the largest crop acreage devoted to an ornamental crop, pumpkins. The next largest vegetable crops are sweet corn and tomatoes, with all others representing negligible commercial, fresh market acreage. For a food hub to be viable, an increase in production and diversity would be required. Otherwise, it would be impractical to gather and distribute wholesale quantities of vegetables to restaurants, retailers, or wholesalers. Interviews with County farmers confirmed that market opportunity is not limited by facility-based services, such as aggregation, but instead were limited by programmatic and policy restrictions. Chief among their concerns are the impending food safety certification requirements imposed by the federal Food Safety Modernization Act audited by Good Agricultural Practices (GAP) certification. These regulations, which were previously enforced only on the largest farms, now apply to all fruit and vegetable producers, regardless of farm size or program cost. Unless these standards are adopted at the farm level, local producers would be barred from many, if not all, commercial sales. Further evidence that a facility-based food hub is unlikely to be successful in Howard County can be found in the depth and breadth of the existing food supply chain. Howard County is the epicenter of a 100-mile radius supply chain that includes approximately 4,000 firms that are involved in all aspects of the food industry, including logistics, manufacturing, and distribution. After interviewing businesses operating in these sectors, it was determined that sufficient options to aggregate, ship, or value add were available in the market, but that critical services, such as quality assurance, food safety certification, and marketing support were lacking, putting local farmers at a marked disadvantage over farms from outside the area. Given the above, the project team concluded that it would be a greater benefit to our client if further research and project development efforts were directed toward designing a multi-pronged Quality Assurance Program for the County combined with an associated marketing and brand management program to raise awareness of Howard County farm products. This multifaceted approach strives to implement the newly emerging food safety requirements as a method of expansion into new markets. This allows growers to participate in the supply-chain where well-documented demand for local, GAP-certified produce and quality assured beef cattle exists. The second facet of the approach involves creating a suite of strategic marketing initiatives designed to bolster consumer demand for local food., Howard County