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Full-Text Articles in Life Sciences

Cover Crop Effect On Subsequent Wheat Yield In The Central Great Plains, David C. Nielsen, Drew J. Lyon, Robert K. Higgins, Gary W. Hergert, Johnathon D. Holman, Merle F. Vigil Oct 2016

Cover Crop Effect On Subsequent Wheat Yield In The Central Great Plains, David C. Nielsen, Drew J. Lyon, Robert K. Higgins, Gary W. Hergert, Johnathon D. Holman, Merle F. Vigil

David C. Nielsen

Crop production systems in the water-limited environment of the semiarid central Great Plains may not have potential to profitably use cover crops because of lowered subsequent wheat (Triticum asestivum L.) yields following the cover crop. Mixtures have reportedly shown less yield-reducing effects on subsequent crops than single-species plantings. This study was conducted to determine winter wheat yields following both mixtures and single-species plantings of spring-planted cover crops. The study was conducted at Akron, CO, and Sidney, NE, during the 2012–2013 and 2013–2014 wheat growing seasons under both rainfed and irrigated conditions. Precipitation storage efficiency before wheat planting, wheat water use, …


Cover Crop Biomass Production And Water Use In The Central Great Plains, David C. Nielsen, Drew J. Lyon, Gary W. Hergert, Robert K. Higgins, Johnathon D. Holman Aug 2015

Cover Crop Biomass Production And Water Use In The Central Great Plains, David C. Nielsen, Drew J. Lyon, Gary W. Hergert, Robert K. Higgins, Johnathon D. Holman

David C. Nielsen

The water-limited environment of the semiarid Central Great Plains may not produce enough cover crop biomass to generate benefits associated with cover crop use in more humid regions. There have been reports that cover crops grown in mixtures produce more biomass with greater water use efficiency than single-species plantings. This study was conducted to determine differences in cover crop biomass production, water use efficiency, and residue cover between a mixture and single-species plantings. The study was conducted at Akron, CO, and Sidney, NE, during the 2012 and 2013 growing seasons under both rainfed and irrigated conditions. Water use, biomass, and …


Cover Crop Mixtures Do Not Use Water Differently Than Single-Species Plantings, David C. Nielsen, Drew J. Lyon, Gary W. Hergert, Robert K. Higgins, Francisco J. Calderon, Merle F. Vigil Jan 2015

Cover Crop Mixtures Do Not Use Water Differently Than Single-Species Plantings, David C. Nielsen, Drew J. Lyon, Gary W. Hergert, Robert K. Higgins, Francisco J. Calderon, Merle F. Vigil

David C. Nielsen

Recent recommendations advocating the use of cover crop mixtures instead of single-species in semi-arid environments require rigorous scientific studies. One of those stated benefits is greatly reduced water use by cover crops grown in mixtures. The objectives of this study were to characterize soil water extraction patterns and determine water use of cover crops grown in single species plantings and in a 10-species mixture and to compare cover crop water use to evaporative water loss from no-till fallow. The study was conducted at Akron, CO, and Sidney, NE, during the 2012 and 2013 growing seasons on silt loam soils. At …


Modeling Grain Yield And Straw Yield Of Wheat Using Back Propagation And Genetic Algorithm, Omar Maghawri Ibrahim Hassan Dr. Dec 2014

Modeling Grain Yield And Straw Yield Of Wheat Using Back Propagation And Genetic Algorithm, Omar Maghawri Ibrahim Hassan Dr.

Dr. Omar Maghawri Ibrahim

The first objective of this study was to model the effect of yield components, number of grain/spike, number of spikes/m2, and 1000 kernels weight on the grain yield and straw yield of wheat. An artificial neural network (ANN), multilayer perceptron feed forward neural network (MLP) was used for developing the predictive model. Two different training algorithms: back propagation (BP) and genetic algorithm (GA) were used to train the MLP which structured of three neurons in the input layer, one hidden layer of six neurons, and two neurons in the output layer. The second objective of the current study was to …


Influence Of Nitrogen Fertilizer And Foliar Application Of Salicylic Acid On Wheat, Omar Maghawri Ibrahim Hassan Dr. Nov 2014

Influence Of Nitrogen Fertilizer And Foliar Application Of Salicylic Acid On Wheat, Omar Maghawri Ibrahim Hassan Dr.

Dr. Omar Maghawri Ibrahim

Two cemented plots experiments were carried out during the winter seasons of 2012/2013 and 2013/2014, Soil Salinity Laboratory, Alexandria, Egypt, to study the effect of three levels of salicylic acid (SA) (0, 50, 100 ppm) and three rates of nitrogen fertilizer (75, 100, 125 kg N/feddan) on yield and yield components of wheat (Sakha 93). The experimental design was split plot with four replicates. The results indicated that increasing nitrogen fertilizer rates resulted in significant increase in plant height (cm), number of grain/spike, number of spikes/m2, 1000 grain weight (gm), grain yield (gm/plot), straw yield (gm/plot), and biological yield (gm/plot). …


Performance Assessment Of Some Flax (Linum Usitatissimum L.) Varieties Using Cluster Analysis Under Sandy Soil Conditions, Omar Maghawri Ibrahim Hassan Dr. Jul 2014

Performance Assessment Of Some Flax (Linum Usitatissimum L.) Varieties Using Cluster Analysis Under Sandy Soil Conditions, Omar Maghawri Ibrahim Hassan Dr.

Dr. Omar Maghawri Ibrahim

To assess the performance and the variability of 49 flax varieties based on agronomic parameters using cluster analysis, a field experiment was conducted in 2011/2012 and 2012/2013 winter seasons at the farm of the National Research Center at Nubria district, Albehira Governorate, Egypt. The results revealed high significant difference among all flax varieties in all the studied characters. Letwania-9 and Evelen cultivars surpassed all other varieties in seed and oil yields/ fed. On the other hand, D variety gave the lowest value of seed yield/fed and F variety gave the lowest values of oil% and oil yield/fed. While, G Variety …


Travelling In Cuba, Fathi Habashi Feb 2013

Travelling In Cuba, Fathi Habashi

Fathi Habashi

Contact with Cuban scientists was established in 1986 when two researchers from Centro de Investigaciones para Industria Minero Metalurgica in Havana visited Laval University to get acquainted with research activities in the area of extractive metallurgy. This was followed in early 1987 by two more researchers from the same centre. Invitations were then received in late 1987, 1989, and 2008 to visit the nickel refineries in Cuba and to hold seminars at the University of Havana. The present report outlines these activities.


Deep Pipe Irrigation, David A. Bainbridge Jan 2013

Deep Pipe Irrigation, David A. Bainbridge

David A Bainbridge

Deep pipe irrigation uses a vertically placed section of pipe to deliver water to the roots of plants. This reduces evaporation and increases water use efficiency. Deep pipes can be filled by hand, drip or rainwater catchment.


Planting Desert Sites, David A. Bainbridge Jan 2013

Planting Desert Sites, David A. Bainbridge

David A Bainbridge

Desert planting requires great care in preparing plants, handling plants and planting. With proper consideration of soil, climate and water availability plants can be established despite severe conditions of high temperatures, high winds, herbivory and lack of water.


Container Plants For Desert Restoration, David A. Bainbridge Jan 2013

Container Plants For Desert Restoration, David A. Bainbridge

David A Bainbridge

Container planting is essential for most desert restoration work because direct seeding is rarely successful. The containers best suited for desert planting are often taller (deeper) to facilitate root development. Fertilizer management, inoculation, irrigation and pruning can be used to maximize root growth with minimal shoot development.


What's In Your Nitrogen Budget?, Robert Mikkelsen Aug 2012

What's In Your Nitrogen Budget?, Robert Mikkelsen

Robert Mikkelsen

No abstract provided.


Crop Modeling, Omar Maghawri Ibrahim Hassan Dr. Mar 2012

Crop Modeling, Omar Maghawri Ibrahim Hassan Dr.

Dr. Omar Maghawri Ibrahim

No abstract provided.


Simulation Of Barley Grain Yield Using Artificial Neural Networks And Multiple Linear Regression Models, Omar Maghawri Ibrahim Hassan Jan 2012

Simulation Of Barley Grain Yield Using Artificial Neural Networks And Multiple Linear Regression Models, Omar Maghawri Ibrahim Hassan

Dr. Omar Maghawri Ibrahim

Developing models for simulation of barley grain yield is important for making early prediction. To simulate barley grain yield, a simple and advanced modeling techniques were used based on a field experiment that was conducted using 40 foreign barley genetic resources from 2007/08 to 2008/09 winter seasons at Kalubia Governorate, Egypt. The barley genotypes were imported from International Center for Agricultural Research in Dry Areas (ICARDA), Syria. Artificial neural network (ANN) and multiple linear regression (MLR) models were developed to simulate barley grain yield. The models were constructed using the first year of field data and validated with the second …


Super Efficient Irrigation With Buried Clay Pots, David A. Bainbridge Jan 2012

Super Efficient Irrigation With Buried Clay Pots, David A. Bainbridge

David A Bainbridge

Buried clay pot irrigation was first described in an agricultural extension bulletin in China more than 2000 years ago. The clay pot provides demand responsive irrigation at very high efficiency. Clay pot irrigation can be 5-10 times more efficient than conventional irrigation. It is being used more widely in Asia, Africa, Latin American and the US.


Pyrite. History, Chemistry, And Metallurgy, Fathi Habashi Jan 2012

Pyrite. History, Chemistry, And Metallurgy, Fathi Habashi

Fathi Habashi

The Book covers the history of pyrite - - how it was a strategic mineral necessary for the production of elemental sulfur needed for making gunpowder for military purposes and for the production of SO2 needed for making sulfuric acid for the chemical industry. Now its presence is a nuisance in tailings ponds. The book also covers the processing of pyrite containing gold, its chemistry and technology, the processing of pyrite cinder for the production of a variety of metals, and its behaviour towards autotrophic microorganisms.


Construction Of The Next Generation Of Energy Efficient Light Boxes - Sponsored By Bayer Environmental Science, Gregory Keith Bartley Jr. Oct 2011

Construction Of The Next Generation Of Energy Efficient Light Boxes - Sponsored By Bayer Environmental Science, Gregory Keith Bartley Jr.

Gregory Keith Bartley Jr.

This short presentation includes an overview of features that went into constructing a new type of light box technology utilizing low-power usage LEDs and Low Density flexible Polymers. This light box was constructed for digital image analysis of plant health and ground cover using a Canon Powershot G12 camera and Sigma Scan Digital Image Analysis Software.


Constructing New Technology: The Crop Circle Gps Cart In Pictures, Gregory Keith Bartley Jr., Brandon J. Horvath Sep 2011

Constructing New Technology: The Crop Circle Gps Cart In Pictures, Gregory Keith Bartley Jr., Brandon J. Horvath

Gregory Keith Bartley Jr.

The crop circle spectrometer represents a breakthrough in unbiased sensor data. Unlike traditional passive sensors, it pulses light at a speed of 20,000 times per second. With this comes the ability of these filters to discern reflectance measurements from that of natural sunlight, allowing it to be used in environments of sun, shade, and even darkness. From these various reflectance values at different wavelengths, we get measurements of plant health known as vegetation indices. And different vegetation indices can tell us different things about the health of a plant. Couple this with the recent advances in GPS technology, we can …


Magnesium: An Overlooked Nutrient?, Robert Mikkelsen Jun 2011

Magnesium: An Overlooked Nutrient?, Robert Mikkelsen

Robert Mikkelsen

Magnesium nutrition of plants is frequently overlooked and shortages can adversely impact plant growth. Many essential functions require adequate Mg supplies... the most visible being its role in chlorophyll and photosynthesis... but less visible reactions are also dependent on an adequate supply of Mg. When needed, a variety of soluble and slowly soluble Mg sources are available to meet crop demands.


Metalurgia Extractiva Y Política Nacional, Fathi Habashi Jan 2011

Metalurgia Extractiva Y Política Nacional, Fathi Habashi

Fathi Habashi

Should a country export its mineral wealth in form of concentrates or should it locally treat its ores to produce metals as final products? In the past centuries pyrometallurgy was the only route to extract metals from ores and this required a large capital investment many countries could not afford to raise. This situation encouraged marketing of concentrates. Today, metallurgists have the option to use the hydrometallurgical route to process ores and concentrates at a reasonable capital investment. This opened the way to the possibility of processing ores locally. When need arises to increase production new units can be added …


Leaching Mechanism Of Semiconducting Minerals, Fathi Habashi Dec 2010

Leaching Mechanism Of Semiconducting Minerals, Fathi Habashi

Fathi Habashi

The mechanism of leaching of semiconducting minerals such as PbS, ZnS, UO2, etc., has been the subject of intensive speculation by hydrometallurgists in the early 1950s. The electrochemical mechanism proposed in 1970 by the author in volume 2 of his Principles of Extractive Metallurgy avoids the assumption of forming intermediate complexes that cannot be isolated or identified.


Metals: Typical And Less Typical, Transition And Inner Transition, Fathi Habashi Mar 2010

Metals: Typical And Less Typical, Transition And Inner Transition, Fathi Habashi

Fathi Habashi

While most chemists agree on what is a metal and what is a non-metal there is a disagreement with respect to what is a metalloid and what is a transition metal. It is believed that this problem can be solved if two new terms are adopted: typical and less typical metals. These new terms will also help reconcile the European Periodic Table versus the North American regarding numbering of groups as well as the IUPAC numbering which could be as well abandoned in favour of group names as will be shown in the manuscript.


Phosphate Industry And The Radon Problem, Fathi Habashi Feb 2010

Phosphate Industry And The Radon Problem, Fathi Habashi

Fathi Habashi

The problem of radon generated during the treatment of phosphate rock by sulfuric acid to produce fertilizers can be solved by using nitric acid. In this case radium, which is the source of radon, goes into solution and can be precipitated by a controlled method and safely disposed of. A variety of options are discussed. Text in Farsi with English translation.


Aqua Science Through The Ages. An Illustrated History Of Water, Fathi Habashi Jan 2010

Aqua Science Through The Ages. An Illustrated History Of Water, Fathi Habashi

Fathi Habashi

Water a component of the Four Elements considered by the ancient philosophers as essential for survival, played, and is still playing an essential role in society. Great civilizations in ancient times developed along great rivers. The ancient peoples knew how to manage water supplies by digging canals, controlling floods, and using water for irrigation. They designed equipment that used water to measure the time, to determine the density of solids, to fight fires, and to create vacuum. Modern engineers exploited water flow to design and construct huge hydroelectric power stations. Waterways and navigation systems were also an essential element for …


Screening Of 40 Triticale (X Triticosecale Wittmack) Genotypes Under Sandy Soil Conditions, Omar Maghawri Ibrahim Hassan Jan 2009

Screening Of 40 Triticale (X Triticosecale Wittmack) Genotypes Under Sandy Soil Conditions, Omar Maghawri Ibrahim Hassan

Dr. Omar Maghawri Ibrahim

No abstract provided.


Chemistry And Metallurgy In The Great Empires, Fathi Habashi Jan 2009

Chemistry And Metallurgy In The Great Empires, Fathi Habashi

Fathi Habashi

It is remarkable that certain countries expand to become great empires then as time goes by they gradually decline while others rise. This book attempts to briefly trace the history of chemistry and metallurgy through the different empires that became at one time great and then faded away. In 272 pages 21.5 x 28 cm, the author outlines the inter-relation of chemistry, metallurgy, mining, and medicine, the idea of the divinity of kings and the formation of nations, and finally the rise and fall of the empires. He then covers the ancient and medieval empires, followed by the empires from …


Science, Technology, And Society, Fathi Habashi Jan 2009

Science, Technology, And Society, Fathi Habashi

Fathi Habashi

Science, technology, and society is a vast and complex question. It is discussed here from five points: social responsibility of scientists, migration and movement of scholars, philanthropy and its role in education and culture, enlightened despots and their influence on science and culture, and finally the social aspects of mining. The book is meant for the general reader but can benefit scientists as well. It is fully illustrated with colored pictures. It is hoped that it will serve as an introduction to this field to the young generation and inspire them to serve society.


Climate Change And Freshwater Resources, Noah D. Hall, Bret B. Stuntz, Robert H. Abrams Jan 2008

Climate Change And Freshwater Resources, Noah D. Hall, Bret B. Stuntz, Robert H. Abrams

Noah D Hall

The Earth’s climate is warming. This is the unequivocal conclusion of climate scientists. Despite the complexities of climatology, certain consistent trends emerge with implications for water availability: as the world gets warmer, it will experience increased regional variability in precipitation, with more frequent heavy precipitation events and more susceptibility to drought. These simple facts will have a profound impact on freshwater resources throughout the United States, as the warmer climate will reduce available water supplies and increase water demand. Unfortunately, current water law and policy are not up to the new challenges of climate change and resulting pressures on freshwater …


Risks, Farmers’ Suicides And Agrarian Crisis In India: Is There A Way Out?, Srijit Mishra Jan 2008

Risks, Farmers’ Suicides And Agrarian Crisis In India: Is There A Way Out?, Srijit Mishra

Srijit Mishra

Poor returns to cultivation and absence of non-farm opportunities are indicative of the larger socio-economic malaise in rural India. This is accentuated by the multiple risks that the farmer faces – yield, price, input, technology and credit among others. The increasing incidence of farmers’ suicides is symptomatic of a larger crisis, which is much more widespread. Risk mitigation strategies should go beyond credit. Long term strategies requires more stable income from agriculture, and more importantly, from non-farm sources. Private credit and input markets need to be regulated. A challenge for the technological and financial gurus is to provide innovative products …


The Potential Role Of Probiotics In Reducing Poverty-Associated Infections In Developing Countries, Kingsley C. Anukam Oct 2007

The Potential Role Of Probiotics In Reducing Poverty-Associated Infections In Developing Countries, Kingsley C. Anukam

Kingsley C Anukam

Probiotics are defined by the Food and Agricultural Organization/ World Health Organization as “live microorganisms which when administered in adequate amounts confer a health benefit on the host” [1]. The potential benefits of their use have not been adequately investigated, especially in the developing world. Japan introduced Yakult, a probiotic fermented food drink in 1935, and in the Northern hemisphere, research and use of probiotics has gained an unprecedented momentum in the last decade [2]. Use of probiotics is not uncommon in Europe [3], but in many developing countries use of probiotics in its present definition is a foreign concept. …


Effects Of Cowpea Fortification And The Level Of Ripeness Of Plantain On The Nutritive Value Of Plantain Based Snack Foods , Ann Etsey, Esther Sakyi-Dawson, Samuel Sefa-Dedeh, Emmanuel Afoakwa, Kwaku Tano-Debrah, George Annor Apr 2007

Effects Of Cowpea Fortification And The Level Of Ripeness Of Plantain On The Nutritive Value Of Plantain Based Snack Foods , Ann Etsey, Esther Sakyi-Dawson, Samuel Sefa-Dedeh, Emmanuel Afoakwa, Kwaku Tano-Debrah, George Annor

George Amponsah Annor Mr.

To investigate effects of cowpea addition and level of ripeness of plantain on the nutritional and sensory characteristics of Kaklo and Ofam in Ghana, A 2X4 factorial experiment with firm and soft ripe plantain and cowpea fortification of 0, 10, 20 and 30% was designed. The proximate composition and acceptability of products using a 7-point hedonic scale were evaluated. With the addition of 30% cowpea, the protein content of the Kaklo from the firm ripe and soft ripe plantain increased from 2.92% to 7.32% and 3.65% to 8.05% respectively, whilst the protein of the Ofam from the firm and soft …