Effect of carrier and temperature on the viability of Burkholderia sp (UPMB3) and Pseudomonas sp (UPM P3) during storage.

This study was aimed at to determine the ability of different carriers to sustain the viability and efficacy of endophytic bacteria: Burkholderia sp (UPMB3) and Pseudomonas sp(UPMP3) during storage. UPMB3 and UPMP3 were formulated as dry formulation using vermiculite and coir dust as carriers and liquid formulation with Luria broth (LB) as the culture substrate. These bacterial formulations developed were assessed for the viability and efficacy as fresh preparations and after nine months stored at 10, 20 and 30°C. Formulations stored at 10 and 20°C provided a longer shelf-life than those stored at 30°C based on viability at monthly intervals over a 9-month storage period. At 10 and 20°C, the LB-based and vermiculite-based formulations were found to be the most stable by sustaining 86% of viable bacteria cells after 6 months of storage. However, at the end of 9 months, the number of viable bacteria cells in both formulations declined to 71 and 57%, respectively. Coir dust-based formulation was the least stable at 10 and 20°C storage, when only 43 and 29% viable cells were detected at the end of 9-months storage

The processing and impact of dissolved riverine nitrogen in the Arctic Ocean

© The Author(s), 2011. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Estuaries and Coasts 35 (2012): 401-415, doi:10.1007/s12237-011-9417-3.Although the Arctic Ocean is the most riverine-influenced of all of the world’s oceans, the importance of terrigenous nutrients in this environment is poorly understood. This study couples estimates of circumpolar riverine nutrient fluxes from the PARTNERS (Pan-Arctic River Transport of Nutrients, Organic Matter, and Suspended Sediments) Project with a regionally configured version of the MIT general circulation model to develop estimates of the distribution and availability of dissolved riverine N in the Arctic Ocean, assess its importance for primary production, and compare these estimates to potential bacterial production fueled by riverine C. Because riverine dissolved organic nitrogen is remineralized slowly, riverine N is available for uptake well into the open ocean. Despite this, we estimate that even when recycling is considered, riverine N may support 0.5–1.5 Tmol C year−1 of primary production, a small proportion of total Arctic Ocean photosynthesis. Rapid uptake of dissolved inorganic nitrogen coupled with relatively high rates of dissolved organic nitrogen regeneration in N-limited nearshore regions, however, leads to potential localized rates of riverine-supported photosynthesis that represent a substantial proportion of nearshore production.Funding for this work was provided through NSFOPP- 0229302 and NSF-OPP-0732985.Support to SET was additionally provided by an NSERC Postdoctoral Fellowship

Foreign equity portfolio flow and corruption: a cross-country evidence

This study examines the impact of foreign equity portfolio investment on corruption. Employing a large dataset of 44 countries from 2001 to 2015 and three different measures of corruption, our results show that foreign investors from well-governed countries tend to foster public accountability, reduce asymmetry information and corruption. We find empirical evidence that foreign equity portfolio investment interacts with stock market development and central bank transparency to reduce corruption. Our results suggest that stock market development and central bank transparency are regarded as complementary by international portfolio investors. Further analysis indicates that corruption appears more prevalent in countries where domestic investors dominate the stock market. Our results are robust to endogeneity using dynamic generalized methods of moments (GMM). The findings suggest that attracting foreign equity investors reduces corruption, implying significant benefits for portfolio diversification

Dissolved organic matter (DOM) in the estuaries of Ob and Yenisei and the adjacent Kara Sea, Russia

Based on observations during four scientific expeditions to the Kara Sea and the Siberian rivers Ob and Yenisei we determined the discharge, distribution and characteristics of dissolved organic matter (DOM). Surface concentrations of dissolved organic carbon (DOC) ranged from 151 IlM C in the northern Kara Sea to 939 IlM C in the river Ob. The estimated annual mean DOC concentration in the Yenisei (681 IlM C) was slightly higher than in the Ob (640 IlM C). Dissolved organic nitrogen (DON) concentrations typically varied between 5 and 15 IlM N with higher values in the rivers. Freshwater discharge and DOC concentrations experienced pronounced seasonal variations strongly affecting the spatial and temporal distribution of DOM in the Kara Sea. The largely conservative distribution of DOC and DON along the salinity gradient indicated the predominantly refractory character of riverine DOM. This observation was consistent with laboratory experiments, which showed only minor losses due to flocculation processes and bacterial consumption. Optical properties and relatively high C/N ratios (19 to 51) of DO M suggest that a large fraction of river DOM is of terrestrial origin and that phytoplankton contributed little to DOM on the Kara Sea shelf during the sampling periods. Together, the rivers Ob and Yenisei discharge about 8 Tg DOC yr- I into the Kara Sea. Due to the absence of efficient removal mechanisms in these estuaries the majority of riverine DOM appears to pass the estuarine mixing zone and is transported towards the Arctic Ocean