NEBRASKA AGRICULTURAL WATER MANAGEMENT DEMONSTRATION NETWORK (NAWMDN): INTEGRATING RESEARCH AND EXTENSION/OUTREACH

Maximizing the net benefits of irrigated plant production through appropriately designed agricultural water management programs is of growing importance in Nebraska, and other western and Midwestern states, because many areas are involved in management and policy changes to conserve irrigation water. In Nebraska, farmers are being challenged to practice conservation methods and use water resources more efficiently while meeting plant water requirements and maintaining high yields. Another challenge Nebraska experiences in it\u27s approximately 3.5‐million‐ha irrigated lands is limited adoption of newer technologies/tools to help farmers better manage irrigation, conserve water and energy, and increase plant water use efficiency. In 2005, the Nebraska Agricultural Water Management Demonstration Network (NAWMDN or Network) was formed from an interdisciplinary team of partners including the Natural Resources Districts (NRD); USDA‐NRCS; farmers from south central, northeast, west central, and western Nebraska; crop consultants; and University of Nebraska‐Lincoln faculty. The main goal of the Network is to enable the transfer of high quality research‐based information to Nebraskans through a series of demonstration projects established in farmers\u27 fields and implement newer tools and technologies to address and enhance plant water use efficiency, water conservation, and reduce energy consumption for irrigation. The demonstration projects are supported by the scientifically‐based field research and evaluation projects conducted at the University of Nebraska‐Lincoln, South Central Agricultural Laboratory located near Clay Center, Nebraska. The Network was formed with only 15 farmers as collaborators in only one of the 23 NRDs in 2005. As of late 2009, the number of active collaborators has increased to over 300 in 12 NRDs and 35 of 93 counties. The Network is impacting both water and energy conservation due to farmers adopting information and newer technologies for irrigation management. The NAWMDN is helping participants to improve irrigation management and efficiency by monitoring plant growth stages and development, soil moisture, and crop evapotranspiration. As a result, they are reducing irrigation water application amounts and associated energy savings is leading to greater profitability to participating farmers. This article describes the goals and objectives of the Network, technical and educational components, operational functions, and procedures used in the NAWMDN. The quantitative impacts in terms of water and energy conservation are reported

Nebraska Agricultural Water Management Demonstration Network (NAWMDN): Integrating Research and Extension/Outreach

Maximizing the net benefits of irrigated plant production through appropriately designed agricultural water management programs is of growing importance in Nebraska, and other western and Midwestern states, because many areas are involved in management and policy changes to conserve irrigation water. In Nebraska, farmers are being challenged to practice conservation methods and use water resources more efficiently while meeting plant water requirements and maintaining high yields. Another challenge Nebraska experiences in it\u27s approximately 3.5‐million‐ha irrigated lands is limited adoption of newer technologies/tools to help farmers better manage irrigation, conserve water and energy, and increase plant water use efficiency. In 2005, the Nebraska Agricultural Water Management Demonstration Network (NAWMDN or Network) was formed from an interdisciplinary team of partners including the Natural Resources Districts (NRD); USDA‐NRCS; farmers from south central, northeast, west central, and western Nebraska; crop consultants; and University of Nebraska‐Lincoln faculty. The main goal of the Network is to enable the transfer of high quality research‐based information to Nebraskans through a series of demonstration projects established in farmers\u27 fields and implement newer tools and technologies to address and enhance plant water use efficiency, water conservation, and reduce energy consumption for irrigation. The demonstration projects are supported by the scientifically‐based field research and evaluation projects conducted at the University of Nebraska‐Lincoln, South Central Agricultural Laboratory located near Clay Center, Nebraska. The Network was formed with only 15 farmers as collaborators in only one of the 23 NRDs in 2005. As of late 2009, the number of active collaborators has increased to over 300 in 12 NRDs and 35 of 93 counties. The Network is impacting both water and energy conservation due to farmers adopting information and newer technologies for irrigation management. The NAWMDN is helping participants to improve irrigation management and efficiency by monitoring plant growth stages and development, soil moisture, and crop evapotranspiration. As a result, they are reducing irrigation water application amounts and associated energy savings is leading to greater profitability to participating farmers. This article describes the goals and objectives of the Network, technical and educational components, operational functions, and procedures used in the NAWMDN. The quantitative impacts in terms of water and energy conservation are reported

Corporate political activity in less developed countries:The Volta River Project in Ghana, 1958-66

The article expands existing categorisations of political and economic governance by including literature on less developed countries (LDCs). In four consecutive negotiations between the US multinational Kaisers and the US and Ghana governments in the early 1960s, it is argued that the company reached levels of influence that are at odds with existing explanations. In order to understand corporate political activities in LDCs, analysis needs to go beyond static factors (political risk) and include dynamic factors such as diplomatic relations and 'arenas of power', and consider the role of the investor's home country relative to the host economy

Latent heat induced rotation limited aggregation in 2D ice nanocrystals

The basic science responsible for the fascinating shapes of ice crystals and snowflakes is still not understood. Insufficient knowledge of the interaction potentials and the lack of relevant experimental access to the growth process are to blame for this failure. Here, we study the growth of fractal nanostructures in a two-dimensional (2D) system, intercalated between mica and graphene. Based on our scanning tunneling spectroscopy data, we provide compelling evidence that these fractals are 2D ice. They grow while they are in material contact with the atmosphere at 20°C and without significant thermal contact to the ambient. The growth is studied in situ, in real time and space at the nanoscale. We find that the growing 2D ice nanocrystals assume a fractal shape, which is conventionally attributed to Diffusion Limited Aggregation (DLA). However, DLA requires a low mass density mother phase, in contrast to the actual currently present high mass density mother phase. Latent heat effects and consequent transport of heat and molecules are found to be key ingredients for understanding the evolution of the snow (ice) flakes. We conclude that not the local availability of water molecules (DLA), but rather them having the locally required orientation is the key factor for incorporation into the 2D ice nanocrystal. In combination with the transport of latent heat, we attribute the evolution of fractal 2D ice nanocrystals to local temperature dependent rotation limited aggregation. The ice growth occurs under extreme supersaturation, i.e., the conditions closely resemble the natural ones for the growth of complex 2D snow (ice) flakes and we consider our findings crucial for solving the "perennial" snow (ice) flake enigma

Retraction

Our report “ultrahigh magnetoresistance at room temperature in molecular wires” (1) presents measurements on onedimensional molecular chains confined inside the nanochannels of zeolite L crystals. In these measurements, we observed signals that were interpreted as an exceptionally large (~1000%) response of the conductance through the molecular chains to an external magnetic field of a few millitesla. The explanation of the results was based on a room-temperature Pauli spin blockade effect, intrinsic to the hopping transport through the molecules. The observed magnetic field scale of a few millitesla could be explained by the typical magnitude of the random nuclear magnetic field in the molecular environment. The shape of the conductance versus magnetic field dependence was found to be in close agreement with similar curves observed in bulk organic semiconductors, in which the effect is referred to as “organic magnetoresistance” or “OMAR.” The exceptionally large effect in our case was ascribed to the one-dimensional nature of electron transport along the molecular chains. In follow-up research by some of the coauthors, suspicion arose with regard to data collected by the first author Rabindra N. Mahato, which led to a thorough investigation by the co-authors. This investigation has revealed inappropriate data handling by Dr. Mahato, such that the experimental results are not accurately represented in the paper. This makes it, in our eyes, impossible to solidly underpin the conclusions made in the report. All co-authors have therefore concluded that the paper should be immediately retracted. Dr. Mahato has agreed to this Retraction

Dual modulation STM: Simultaneous high-resolution mapping of the differential conductivity and local tunnel barrier height demonstrated on Au(111)

We present a scanning tunneling microscopy (STM) technique to simultaneously measure the topography, the local tunnel barrier height (dI/dZ), and the differential conductivity (dI/dV). We modulate the voltage and tip piezo with small sinusoidal signals that exceed the cut-off frequency of the STM electronics and feed the tunneling current into two lock-in amplifiers (LIAs). We derive and follow a set of criteria for the modulation frequencies to avoid any interference between the LIA measurements. To validate the technique, we measure Friedel oscillations and the subtle tunnel barrier difference between the hcp and fcc stacked regions of the Au(111) herringbone reconstruction. Finally, we show that our method is also applicable to open feedback loop measurements by performing grid I(V) spectroscopy