Row Cleaners in No-Till Corn

Row cleaners are planter attachments mounted in front of the double-disc openers on planters. They are designed to move most of the surface residue to the sides of the row, allowing no-till planting into a band with a fairly clean surface. This attachment is best suited for wet, cool soils to allow a more rapid warming of the soil surface, on rough soil to allow some smoothing before planting, and in heavy residue to prevent hairpinning of residue into the planting slot. There is evidence that cleaning the residue from the row raises soil temperatures which results in quicker corn emergence and sometimes increased yield. The approach has been of particular interest to farmers that are no-tilling wetter and cooler soils early in the spring, where no-till has not been as consistently successful as conventionally tilled systems

Effect of Crop Rotation on Corn and Soybean Yields

Yield of both corn and soybeans has been shown to increase when grown in a rotation as compared to continuous cropping of either of the two crops. These yield improvements are commonly associated with fewer disease, insect and weed problems; better soil tilth; and in the case of corn, a nitrogen contribution from the preceding soybean crop. One or a combination of these factors are believed to have an effect. In the past few decades the yield benefits of rotations were often overlooked as fertilizers and pesticides were used as a substitute for crop rotation. However, research has shown that regardless of all the management inputs, even beyond optimum levels of fertility and pest control, that there is still a yield advantage for rotation from some unknown factor(s) that hasn\u27t been adequately explained. This is commonly called the rotation benefit

Designing Building Blocks for Open-Ended Early Literacy Software

English has a convoluted relationship between its pronunciation and spelling, which obscures its phonological structure for early literacy learners. This convoluted relationship has implications for early literacy software, particularly for open-ended, child-driven designs. A tempting way to bypass this issue is to use manipulables (blocks) that are directly tied to phonemes. However, creating phoneme-based blocks leads to two design challenges: (a) how to represent phonemes visually in a child-accessible way and (b) how to account for context-dependent spelling. In the present work, we approached these challenges by developing a set of animated, onomatopoeia-based mnemonic characters, one per phoneme, that can take the shape of different graphemes.We applied the characters to a construction-based literacy app to simplify independent word-building for literacy beginners. We tested the app during a 13-week-long period with 4- to 5-year-olds in kindergarten classrooms. Children showed visible interest in the characters and properly grasped the principles of their functioning. However, the blocks were not sufficient to scaffold independent word building, leading children to rely on other scaffolding mechanisms. To test the characters' efficiency as mnemonics, we evaluated their effect on the speed and accuracy of finding phonemes on a keyboard. The results suggest that there were both children who benefitted from the characters in this task and those who performed better without them. The factors that differentiated these two categories are currently unclear. To help further research on phonetic mnemonics in literacy learning software, we are making the characters available to the research community.Comment: This is a published manuscript for the paper published in the International Journal of Child-Computer Interaction. Sharing on ArXiv is in accordance with Elsevier sharing polic

Canola: A New Cash Crop for Kentucky

For the past few years, Kentucky farmers have become more interested in alternative cash crops for their farming operations. One such crop that is starting to receive attention is Canola. Classified as an oil crop, Canola is a type of oilseed rape. Rape is a member of the mustard family and is closely related to turnip. cabbage, cauliflower, broccoli and mustards. It is a cool-season annual and an important oilseed crop in many parts of the world that is used for both human consumption and industrial purposes. Major rapeseed production areas are in Europe and Canada. The seed contains approximately 40- 45% oil content (dry basis) and 35% protein (oil-free dry basis). Two products are made from processed rapeseed; an oil that has industrial or edible uses and a high protein meal which can be used in animal feed. There are two types of rape. One type is used for industrial purposes and sometimes called industrial rape. The other is Canola which is used for human and animal consumption. The oil from the varieties of industrial rape contains a high amount of erucic acid (50% or more) and is not suitable for human or animal consumption. It is used in the rubber industry, textiles, detergents, leather, plastics and special lubricants. The meal from these varieties contains high levels of glucosinolates which make it unsuitable for livestock consumption. The current Canola varieties were made possible by breeding improvements which greatly reduced the undesirable components in rapeseed (erucic acid and glucosinolates) and made it suitable for human and animal consumption. The name given to this type of rapeseed is Canola , which is an international registered trademark of the Canola Council of Canada and the name used to identify the modern rapeseed varieties known as double low with 2% or less erucic acid content and less than 30 micromoles of glucosinolates per gram of oil-free meal. One of the strong selling points for Canola oil is its very low saturated fat level and favorable mixture of mono-and polyunsaturated fats. Like other vegetable oils, it contains no cholesterol. Many feel the edible rapeseed oil market will improve as new vegetable oil products made from rapeseed continue to be developed. In addition, there are strong foreign markets, particularly in Europe and Japan, with demand on the increase. The Canola meal is 35% protein and has an economic worth of about 703 the value of soybean meal (44% protein). The value of the meal is also limited by its high fiber and low lysine content

The grazing gait, and implications of toppling table geometry for primate footfall sequences

Many medium and large herbivores locomote forwards very slowly and intermittently when grazing. While the footfall order during grazing is the same as for walking, the relative fore–hind timing—phasing—is quite different. Extended periods of static stability are clearly required during grazing; however, stability requirements are insufficient to account for the timing. Aspects of relatively rapid rolling and pitching—toppling due to the resistance of the back to bending and twisting—can be included in a simplifying geometric model to explain the observation that, in grazing livestock, a step forward with a forefoot is consistently and immediately followed by a step forward from the hind; but not vice versa. The same principles and geometry, but applied to the footfall pattern of walking primates, show that toppling would occur at a different point in the gait cycle. This provides a potential account for the distinctive diagonal-sequence footfall pattern of primates, as it prevents the instant of toppling from being at forefoot placement. Careful and controlled hand positioning would thus be facilitated, presumably beneficial to walking on top of branches, despite a slight energetic cost compared with the usual lateral sequence pattern of horses

Progress on Ultrasonic Flaw Sizing in Turbine Engine Rotor Components: Bore and Web Geometries

The application of generic flaw sizing techniques to specific components generally involves difficulties associated with geometrical complexity and simplifications arising from a knowledge of the expected flaw distribution. This paper is concerned with the case of ultrasonic flaw sizing in turbine engine rotor components. The sizing of flat penny shaped cracks in the web geometry will be discussed and new crack sizing algorithms based on the Born and Kirchhoff approximations will be introduced. Additionally we propose a simple method for finding the size of a flat, penny shaped crack given only the magnitude of the scattering amplitude. The bore geometry is discussed with primary emphasis on the cylindrical focussing of the incident beam. Important questions which are addressed include the effects of diffraction and the position of the flaw with respect to the focal line. The appropriate deconvolution procedures to account for these effects will be introduced. Generic features of the theory will be compared with experiment. Finally, the effects of focused transducers on the Born inversion algorithm are discussed

Genetic relatedness of Salmonella enterica isolates from pens and swine at slaughter

The study aimed to determine if Salmonella enterica isolates from the floor of pre-slaughter holding pens were genetically related to isolates found in swine, held in those pens, post slaughter. Pulsed-field gel electrophoresis (PFGE) typing was used to determine genetic relatedness. On seven occasions, 100% homologous PFGE patterns were found, i.e. the pen and pig isolates were identical. This suggested that pen to pig transfer of Salmonella enterica occurred. Isolates from PFGE patterns associated with pig to pen transfers were more likely to occur in the S. Anatum, S. Heidelberg and S. Typhimurium serotypes. The ability of an isolate from a pen to rapidly infect animals housed in the pen may vary within serotype based on factors described by the PFGE pattern. This may explain why some S. enterica serotypes are prevalent in swine but not in pork products or humans

Book Reviews

Book reviews by Charles S. Desmond, James F. Thornburg, Edward J. Gray, Walter H. E. Jaeger, and Thomas L. Shaffer

Fecal Lactoferrin and Other Stool Markers during Normal Pregnancy and in Inflammatory Bowel Diseases: A Prospective Study and Review of the Literature

Introduction: Management of inflammatory bowel diseases (IBDs) - both Crohn's disease (CD) and ulcerative colitis (UC) - during pregnancy can be challenging since most monitoring tools available in nonpregnant patients are contraindicated.Objectives: The aim of the study was to test whether fecal inflammatory markers - specifically fecal lactoferrin - physiologically change during normal pregnancy as a prerequisite to use them to monitor IBD activity during pregnancy.Methods: Fecal lactoferrin was tested in healthy pregnant and nonpregnant women from the same geographic area and age range (18-40 years) - all negative for clinical gastrointestinal tract inflammation. A retrospective review of fecal lactoferrin levels contrasted with the Simple Endoscopic Score for CD, and the Disease Activity Index for UC was also performed in women with active IBDs within the same age range and geographical area.Results: In 30 nonpregnant subjects, fecal lactoferrin levels were 0.87 \ub1 1.08 mug/g. In 49 pregnant subjects, levels were 0.59 \ub1 0.83, 0.87 \ub1 1.13, and 0.85 \ub1 1.06 mug/g during the first, second, and third trimester, respectively (p = 0.64), with average levels for the 3 trimesters of 0.81 \ub1 1.04 mug/g (p = 0.61 compared to nonpregnant subjects). Sequential fecal lactoferrin levels (n = 26) did not differ from one trimester to the other in the individual subjects (p = 0.80). In 45 female IBD patients (27 with CD and 18 with UC), fecal lactoferrin levels were correlated with disease activity as defined by the endoscopic scores: 218, 688, and 1,175 mug/g for CD and 931, 2,088, and 2,509 mug/g for UC, respectively, for mild, moderate, and severe activity.Conclusions: Fecal lactoferrin levels during normal pregnancy are superimposable to those of nonpregnant women and significantly below levels in women of the same childbearing age with active IBDs. Additional published data - reviewed in this atricle - and our own indicate that fecal lactoferrin and other markers can be potentially used to monitor disease activity in pregnant IBD patients

Age-related neurochemical changes in the rhesus macaque inferior colliculus

Age-related hearing loss (ARHL) is marked by audiometric hearing deficits that propagate along the auditory pathway. Neurochemical changes as a function of aging have also been identified in neurons along the auditory pathway in both rodents and carnivores, however, very little is known about how these neurochemicals change in the non-human primate. To examine how these compensatory neurochemical changes relate to normal aging and audiometric sensitivity along the auditory pathway, we collected auditory brainstem responses (ABRs) and brain specimens from seven rhesus monkeys spanning in age from 15 to 35 years old, and examined the relationship between click evoked ABR thresholds and the ABR evoked pure tone average (PTA) and changes in the number of parvalbumin and NADPH-diaphorase positive cells in the auditory midbrain. We found that the number of parvalbumin positive cells in the central nucleus and the surrounding cortex regions of the inferior colliculus were strongly correlated with advancing age and ABR PTA. We also found that the numbers of NADPHd positive cells in these same regions were not associated with normal aging or changes in the ABR thresholds. These findings suggest that the auditory midbrain undergoes an up-regulation of parvalbumin expressing neurons with aging that is related to changes in the processing of frequencies across the audiometric range