The study evaluated the aseptic establishment of Monstera acuminata Koch and Monstera deliciosa Liebm (Araceae) from leaves and the induction of in vitro organogenesis of M. acuminata K. from stem discs of young shoots. For this purpose, different disinfection protocols were applied to mature leaves and young shoots, from which leaf explants of approximately 1 cm2 and stem discs of approximately 1 mm thickness were extracted. The explants were established in semi-solid media with different hormone treatments during the aseptic establishment stage and induction of organogenesis. Disinfection with 3% sodium hypochlorite (NaClO) for 20 min and 50% Murashige and Skoog[1] medium with plant tissue culture preservative (PPM) favored less oxidation in leaf explants of both species. All explants of M. deliciosa in both treatments grown in PPM-added medium and at different disinfection protocols survived, showed no contamination and more than 80% retained cellular activity up to 49 days of culture age. At 35 days of culture, with disinfection in Tween-20 + 20% ethanol + 2.5% NaClO, and seeding of explants in MS medium added with 1 mg/L of BAP, 0.5 mg/L of AIA and 0.1 mg/L of ANA, seven new shoots of stem discs were induced. Monstera deliciosa was more adaptable to in vitro conditions. Advances in aseptic establishment and induction of organogenesis in native Araceae for wicker production are the basis for ex situ conservation of local populations.
The landlocked and fragile countries’ ability to create a sustainable path to economic growth and poverty reduction is inextricably linked to their export diversification potential, itself related to their connectivity within themselves, in the region, and other external markets. Mali, Chad, and Niger are first challenged by their geography—their landlocked nature with their vast and thinly populated space serves to isolate the most vulnerable communities from external and internal markets. Adding to these geographic disadvantages non-landlocked is incentive environment—defined by high and variable customs common external tariff regimes resulting from multiple overlapping regional trade arrangements—places a wedge between domestic and international prices, provides a disincentive to exports in favor of non-tradable and domestic-oriented sectors. By bringing greater coherence and convergence between the many common external tariff regimes in operation and the rationalization of their structures, and improving connectivity within and between markets, Mali, Chad, Niger, and Guinea can better promote the reallocation of resources toward tradable goods and services, putting the countries on a path toward greater economic inclusion and sustainable growth.
This paper proposes a floating-interest-rate infrastructure bond, where the interest of a government bond is paid to investors during the period of construction and the early period of operation. Unlike the usual government bond, which provides a fixed interest rate, the proposed floating-interest-rate infrastructure bond pays a floating interest, the rate of which depends on spillover tax revenues. Effective infrastructure projects have a positive effect on the economic growth of a region, known as the spillover effect. When user charges and the return from spillover tax revenues are below the fixed rate of the government bond, the interest rate will equal to the fixed rate of the government bond. In this case, investors in the infrastructure will receive interest on the government bond at the minimum rate. As the spillover effect of the infrastructure increases, the rate of return for infrastructure investment will become greater than the fixed rate of the government bond. The success of the floating-interest-rate infrastructure bond depends on the spillover effect and on transparency and accountability. Policy recommendations are provided in this paper on how to increase the spillover effect and improve transparency and accountability.
The porous carbon/Ni nanoparticle composite was prepared by a freeze-drying method using NaCl as the template. It was applied in the effect of the concentration, adsorption time, and temperature of adsorption on the adsorption behavior. The kinetic model and the adsorption isothermic fitting results show that the adsorption behavior fits with the pseudo-secondary dynamics and the Langmuir isothermal model, indicating that the adsorption process is monolayer adsorption. Thermodynamic results indicate that the adsorption process is spontaneous physicochemical adsorption. The fitting showed that the porous carbon/Ni nanoparticle composites reach 217.17 mg·g-1, at 313 K indicates good adsorption for Congo red.
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