53 research outputs found
Economics of Pre-Plant, Topdress, and Variable Rate Nitrogen Application in Winter Wheat
Past research about the efficiency of nitrogen application in winter wheat (Triticum aestivum L.) based on source and timing has produced inconsistent results. The majority of the literature used data from few locations over short time periods. This study used a unique data set of yields and nitrogen quantities from 2002-2009 at ten different locations in Oklahoma, USA. The objective of this research was to determine wheat yield response for granular pre-plant, uniform foliar topdress, and variable rate foliar topdress. Topdress liquid nitrogen had a 19% higher NUE than pre-plant urea, and was the most profitable source of nitrogen.linear stochastic plateau, nitrogen use efficiency, profitability, wheat, Crop Production/Industries,
Reference strip series: Applying your Nitrogen-Rich and Ramp Calibration strips
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Evaluating starter fertilizer applications in grain sorghum production
Starter fertilizers have been documented as a successful practice for several crops. However, information on these fertilizer applications on grain sorghum [Sorghum bicolor (L.) Moench] is very limited. This research was conducted to evaluate the impact of in-furrow starter fertilizers on grain sorghum establishment and yields in the southern Great Plains. Studies were conducted at four sites across Oklahoma in 2014 and two sites in 2015. Trials evaluated eight in-furrow starter fertilizer treatments as well as a non-treated check. Stand counts were collected 1 mo following planting to evaluate impact on stand establishment. At maturity, plot grain weights were used to estimate grain yield. Starter fertilizer applied at high rates (187 L ha-1) reduced stands in four of six site locations by an average of 2.0 plants m-2. This resulted in nearly a 21% decrease in yields. Positive yield effects from in-furrow starter fertilizers were not consistent, with only one location having significantly greater yields compared with the non-treated check. The addition of fertilizer additives did not have a significant effect on sorghum yields. However, with the lack of positive yield results from in-furrow starter fertilizer, it was unexpected that these additives would provide additional yield. These results suggest little yield advantage of in-furrow starter fertilizers in grain sorghum production. Furthermore, if in-furrow starter fertilizers are used in sorghum production, higher application rates could result in decreased stand establishment, potentially resulting in lower yields.Peer reviewedPlant and Soil Science
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Here and now: perceptions of Indian Ocean islanders on the climate change and migration nexus
Empirical studies exploring the links between climate change and migration are increasing. Often, perceptions are not fully explored from the people most affected by the climate change and migration nexus. This article contributes to filling this gap by eliciting and analyzing perceptions regarding climate change and migration from an understudied population labelled as being amongst those most immediately and directly affected by climate change: Indian Ocean islanders. Open-ended, semi-structured interviews were conducted in two case study communities in Maldives (Kaafu Guraidhoo with 17 interviews and Raa Dhuvafaaru with 18 interviews) and two case study communities in Lakshadweep, India (Kavaratti with 35 interviews and Minicoy with 26 interviews). The results present the interviewees’ perceptions of climatic variability and change that they experience; how they perceive the causes of these changes; and links to migration decisions. The interviews demonstrate that perceptions of climate change, of migration, and of the links or lack thereof between the two are centred on the interviewees’ own experiences, their own locations, and the immediate timeframe. External information and direction has limited influence. Their perceptions are framed as being the ‘here and now’ through topophilia (here) and tempophilia (now). The islanders’ views do not avoid, but rather encompass, long-term livelihoods and the future. Such a future might be in another location, but the anchor is expressing future hopes and aspirations through the here and now. It is not linked to the wide-scale, long-term issue of climate change
Transformation, adaptation and development: relating concepts to practice
In recent years there has been a growing number of academic reviews discussing the theme of transformation and its association with adaptation to climate change. On the one hand this has stimulated exchange of ideas and perspectives on the parameters of transformation, but it has also given rise to confusion in terms of identifying what constitutes a non-incremental form of adaptation on the ground. What this article aims to do instead is help researchers and practitioners relate different interpretations of transformation to practice by proposing a typological framework for categorising forms of change that focuses on mechanisms and objectives. It then discusses how these categorisations link to the broader conceptions and critiques noted above, with the idea that this will enable those who seek to analyse or plan adaptation to better analyse what types of action are potentially constitutive of transformation. In doing so, it should equally assist in the identification and specification of critical questions that need to be asked of such activity in relation to issues of sustainability and equity. As the term transformation gains ground in discussions of climate change adaptation, it is necessary to take a step back, review quite what commentators mean when they use the word, and consider the implications on people, especially the most vulnerable and marginalised, of “doing” or promoting transformation in its different forms
Fasting Induces the Expression of PGC-1α and ERR Isoforms in the Outer Stripe of the Outer Medulla (OSOM) of the Mouse Kidney
Peroxisome proliferator-activated receptor-γ co-activator-1α (PGC-1α) is a member of the transcriptional coactivator family that plays a central role in the regulation of cellular energy metabolism under various physiological stimuli. During fasting, PGC-1α is induced in the liver and together with estrogen-related receptor a and γ (ERRα and ERRγ, orphan nuclear receptors with no known endogenous ligand, regulate sets of genes that participate in the energy balance program. We found that PGC-1α, ERRα and ERRγ was highly expressed in human kidney HK2 cells and that PGC-1α induced dynamic protein interactions on the ERRα chromatin. However, the effect of fasting on the expression of endogenous PGC-1α, ERRα and ERRγ in the kidney is not known.In this study, we demonstrated by qPCR that the expression of PGC-1α, ERRα and ERRγ was increased in the mouse kidney after fasting. By using immunohistochemistry (IHC), we showed these three proteins are co-localized in the outer stripe of the outer medulla (OSOM) of the mouse kidney. We were able to collect this region from the kidney using the Laser Capture Microdissection (LCM) technique. The qPCR data showed significant increase of PGC-1α, ERRα and ERRγ mRNA in the LCM samples after fasting for 24 hours. Furthermore, the known ERRα target genes, mitochondrial oxidative phosphorylation gene COX8H and the tricarboxylic acid (TCA) cycle gene IDH3A also showed an increase. Taken together, our data suggest that fasting activates the energy balance program in the OSOM of the kidney
Concurrent validity and test-retest reliability of the Virtual Peg Insertion Test to quantify upper limb function in patients with chronic stroke
Chronic and structural poverty in South Africa: Challenges for action and research
Ten years after liberation, the persistence of poverty is one of the most important and urgent problems facing South Africa. This paper reflects on some of the findings based on research undertaken as part of the participation of the Programme for Land and Agrarian Studies (PLAAS) at the University of the Western Cape in the work of the Chronic Poverty Research Centre (CPRC), situates it within the broader literature on poverty in South Africa, and considers some emergent challenges. Although PLAAS’s survey, being only the first wave of a panel study, does not yet cast light on short term poverty dynamics, it illuminates key aspects of the structural conditions that underpin long-term poverty: the close interactions between asset poverty, employment-vulnerability and subjection to unequal social power relations. Coming to grips with these dynamics requires going beyond the limitations of conventional ‘sustainable livelihoods’ analyses; and functionalist analyses of South African labour markets. The paper argues for a re-engagement with the traditions of critical sociology, anthropology and the theoretical conventions that allow a closer exploration of the political economy of chronic poverty at micro and macro level
Using Grid Soil Sampling to Determine Profit Maximizing Phosphorus Application Rates in Wheat
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