Soil Aggregation, Organic Carbon Concentration, and Soil Bulk Density As Affected by Cover Crop Species in a No-Tillage System

Soil aggregation and the distribution of total organic carbon (TOC) may be affected by soil tillage and cover crops. The objective of this study was to determine the effects of crop rotation with cover crops on soil aggregation, TOC concentration in the soil aggregate fractions, and soil bulk density under a no-tillage system (NTS) and conventional tillage system (CTS, one plowing and two disking). This was a three-year study with cover crop/rice/cover crop/rice rotations in the Brazilian Cerrado. A randomized block experimental design with six treatments and three replications was used. The cover crops (treatments) were: fallow, Panicum maximum, Brachiaria ruziziensis, Brachiaria brizantha, and millet (Pennisetum glaucum). An additional treatment, fallow plus CTS, was included as a control. Soil samples were collected at the depths of 0.00-0.05 m, 0.05-0.10 m, and 0.10-0.20 m after the second rice harvest. The treatments under the NTS led to greater stability in the soil aggregates (ranging from 86.33 to 95.37 %) than fallow plus CTS (ranging from 74.62 to 85.94 %). Fallow plus CTS showed the highest number of aggregates smaller than 2 mm. The cover crops affected soil bulk density differently, and the millet treatment in the NTS had the lowest values. The cover crops without incorporation provided the greatest accumulation of TOC in the soil surface layers. The TOC concentration was positively correlated with the aggregate stability index in all layers and negatively correlated with bulk density in the 0.00-0.10 m layer.

SPATIAL UNCERTAINTY OF NUTRIENT LOSS BY EROSION IN SUGARCANE HARVESTING SCENARIOS

The assessment of spatial uncertainty in the prediction of nutrient losses by erosion associated with landscape models is an important tool for soil conservation planning. The purpose of this study was to evaluate the spatial and local uncertainty in predicting depletion rates of soil nutrients (P, K, Ca, and Mg) by soil erosion from green and burnt sugarcane harvesting scenarios, using sequential Gaussian simulation (SGS). A regular grid with equidistant intervals of 50 m (626 points) was established in the 200-ha study area, in Tabapuã, São Paulo, Brazil. The rate of soil depletion (SD) was calculated from the relation between the nutrient concentration in the sediments and the chemical properties in the original soil for all grid points. The data were subjected to descriptive statistical and geostatistical analysis. The mean SD rate for all nutrients was higher in the slash-and-burn than the green cane harvest scenario (Student’s t-test, p<0.05). In both scenarios, nutrient loss followed the order: Ca>Mg>K>P. The SD rate was highest in areas with greater slope. Lower uncertainties were associated to the areas with higher SD and steeper slopes. Spatial uncertainties were highest for areas of transition between concave and convex landforms.

Micronutrient Accumulation in Conilon Coffee Berries with Different Maturation Cycles

ABSTRACT The number of days between anthesis and maturation of conilon coffee berries varies according to the genotype. Thus, it is believed that periods of greater nutrient demand for fruit formation also vary according to the genotype, directly influencing fertilizer management. The goal of this study was to establish accumulation curves for the micronutrients boron, copper, iron, manganese, and zinc in conilon coffee trees with different maturation cycles. The experiment was conducted in Nova Venécia, State of Espírito Santo, Brazil, during the reproductive cycle of the 2010/2011 crop year. Four coffee genotypes with different maturation cycles (early, intermediate, late, and super-late) were studied. A completely randomized experimental design was used with five replications. The treatments correspond to the accumulation of B, Cu, Fe, Mn, and Zn in the berries every 28 days in the period from flowering to harvest. The early, intermediate, and late genotypes accumulated Fe, Cu, and Mn in a similar manner, with sigmoid curves, whereas the super-late genotype accumulated these nutrients exponentially. Zn was accumulated by all four genotypes following a sigmoid curve. The early, intermediate, and late genotypes accumulated B linearly, whereas the super-late genotype accumulated B following a sigmoid curve. The maturation cycle of the genotype must be taken into account to apply the correct rate of micronutrient fertilization in coffee plantations.

Least Limiting Water Range and Load Bearing Capacity of Soil under Types of Tractor-Trailers for Mechanical Harvesting of Green Sugarcane

ABSTRACT The expansion of the sugarcane industry in Brazil has intensified the mechanization of agriculture and caused effects on the soil physical quality. The purpose of this study was to evaluate the limiting water range and soil bearing capacity of a Latossolo Vermelho distroférrico típico (Rhodic Hapludox) under the influence of different tractor-trailers used in mechanical sugarcane harvesting. The experiment was arranged in a randomized block design with five replications. The treatments consisted of green sugarcane harvesting with: harvester without trailer (T1); harvester with two trailers with a capacity of 10 Mg each (T2); harvester with trailer with a capacity of 20 Mg (T3) and harvester and truck with trailer with a capacity of 20 Mg (10 Mg per compartment) (T4). The least limiting water range and soil bearing capacity were evaluated. The transport equipment to remove the harvested sugarcane from the field (trailer) at harvest decreased the least limiting water range, reducing the structural soil quality. The truck trailer caused the greatest impact on the soil physical properties studied. The soil load bearing capacity was unaffected by the treatments, since the pressure of the harvester (T1) exceeded the pre-consolidation pressure of the soil.

NUTRIENT RECOMMENDATION MODEL FOR CARROT CROP – FERTICALC CARROT

ABSTRACT The literature on fertilization for carrot growing usually recommends nutrient application rates for yield expectations lower than the yields currently obtained. Moreover, the recommendation only considers the results of soil chemical analysis and does not include effects such as crop residues or variations in yield levels. The aim of this study was to propose a fertilizer recommendation system for carrot cultivation (FERTICALC Carrot) which includes consideration of the nutrient supply by crop residues, variation in intended yield, soil chemical properties, and the growing season (winter or summer). To obtain the data necessary for modeling nutritional requirements, 210 carrot production stands were sampled in the region of Alto Paranaíba, State of Minas Gerais, Brazil. The dry matter content of the roots, the coefficient of biological utilization of nutrients in the roots, and the nutrient harvest index for summer and winter crops were determined for these samples. To model the nutrient supply by the soil, the literature was surveyed in regard to this theme. A modeling system was developed for recommendation of macronutrients and B. For cationic micronutrients, the system only reports crop nutrient export and extraction. The FERTICALC which was developed proved to be efficient for fertilizer recommendation for carrot cultivation. Advantages in relation to official fertilizer recommendation tables are continuous variation of nutrient application rates in accordance with soil properties and in accordance with data regarding the extraction efficiency of modern, higher yielding cultivars.

Soil Physical Quality and Soybean Yield as Affected by Chiseling and Subsoiling of a No-Till Soil

ABSTRACT The concept of soil physical quality (SPQ) is currently under discussion, and an agreement about which soil physical properties should be included in the SPQ characterization has not been reached. The objectives of this study were to evaluate the ability of SPQ indicators based on static and dynamic soil properties to assess the effects of two loosening treatments (chisel plowing to 0.20 m [ChT] and subsoiling to 0.35 m [DL]) on a soil under NT and to compare the performance of static- and dynamic-based SPQ indicators to define soil proper soil conditions for soybean yield. Soil sampling and field determinations were carried out after crop harvest. Soil water retention curve was determined using a tension table, and field infiltration was measured using a tension disc infiltrometer. Most dynamic SPQ indicators (field saturated hydraulic conductivity, K0, effective macroporosity, εma, total connectivity and macroporosity indexes [CwTP and Cwmac]) were affected by the studied treatments, and were greater for DL compared to NT and ChT (K0 values were 2.17, 2.55, and 4.37 cm h-1 for NT, ChT, and DL, respectively). However, static SPQ indicators (calculated from the water retention curve) were not capable of distinguishing effects among treatments. Crop yield was significantly lower for the DL treatment (NT: 2,400 kg ha-1; ChT: 2,358 kg ha-1; and DL: 2,105 kg ha1), in agreement with significantly higher values of the dynamic SPQ indicators, K0, εma, CwTP, and Cwmac, in this treatment. The results support the idea that SPQ indicators based on static properties are not capable of distinguishing tillage effects and predicting crop yield, whereas dynamic SPQ indicators are useful for distinguishing tillage effects and can explain differences in crop yield when used together with information on weather conditions. However, future studies, monitoring years with different weather conditions, would be useful for increasing knowledge on this topic.

Supraclavicular flap in head and neck reconstruction: experience in 50 consecutive patients.

The supraclavicular flap (SCF) is a fasciocutaneous flap used to cover head, oral, and neck region defects after tumor resection. Its main vascular supply is the supraclavicular artery and accompanying veins and it can be harvested as a vascularised pedicled flap. The SCF serves as an excellent outer skin cover as well as a good inner mucosal lining after oral cavity and head-neck tumor resections. The flap has a wide arc of rotation and matches the skin colour and texture of the face and neck. Between March 2006 and March 2011, the pedicled supraclavicular flap was used for reconstruction in 50 consecutive patients after head and neck tumor resections and certain benign conditions in a tertiary university hospital setting. The flaps were tunnelized under the neck skin to cover the external cervicofacial defects or passed medial to the mandible to give an inner epithelial lining after the oral cavity and oropharyngeal tumor excision. Forty-four of the 50 patients had 100% flap survival with excellent wound healing. All the flaps were harvested in less than 1 h. There were four cases of distal tip desquamation and two patients had complete flap necrosis. Distal flap desquamation was observed in SCFs used for resurfacing the external skin defects after oral cavity tumor ablation and needed only conservative treatment measures. Total flap failure was encountered in two patients who had failed in previous chemoradiotherapy for squamous cell cancer of the floor of mouth and tonsil, respectively, and the SCF was used in mucosal defect closure after tumor ablation. The benefits of a pedicled fasciocutaneous supraclavicular flap are clear; it is thin, reliable, easy, and quick to harvest. In head, face and neck reconstructions, it is a good alternative to free fasciocutaneous flaps, regional pedicled myocutaneous flaps, and the deltopectoral flap.

Fossil resource depletion and climate change emissions: the role of physical constrictions

[spa] En lo que concierne al cambio climático, los pronósticos de cercanos picos de combustible fósiles parecen buenas noticias pues la mayoría de las emisiones proceden de la quema de combustibles fósiles. Sin embargo, esto podría resultar engañoso de confirmarse las enormes estimaciones de reservas de carbón pues puede divisarse un intercambio de combustible fósiles con baja concentración de carbono (petróleo y gas) por otros de mayor (carbón). Ciñéndonos a esta hipótesis desarrollamos escenarios donde tan pronto el petróleo y el gas natural alcanzan su cénit la extracción de carbón crece lo necesario para compensar el descenso de los primeros. Estimamos las emisiones que se deriva de tales supuestos y las comparamos con el peor escenario del IPCC. Si bien dicho escenario parece improbable concluimos que los picos de petróleo y gas no son suficientes para evitar peligrosas sendas de gases de efecto invernadero. Las concentraciones de CO2 halladas superan con creces las 450 ppm sin signos de remisión.

Iowa Byways: The Official Guide to Iowa Byways, 2013

Browse through this guide and you’ll find the distinct flavor of what is available along each byway. Discover recreational, historic, cultural and scenic attractions using the maps and lists provided in the guide. You’ll find numbered attractions for each byway in or near the town listed. For a comprehensive list of byway features, visit www.iowabyways.org. Friendly local contacts are provided to help you along the way. Iowa Transportation Maps clearly tracking all the Iowa byways with red dotted lines are available at Iowa’s official welcome centers. Traveling Iowa’s byways you will experience small town America, while enjoying diverse landscapes and unique landforms that have been shaped over thousands of years. Iowa’s cultural heritage also plays a major role across all 11 byways, boasting hundreds of historic sites, national landmarks and interpretive centers, each telling Iowa’s stories from the first Native Americans through European immigrants to modern times. Glaciers once covered much of Iowa, shaping the broad flat plains of the prairie. These massive sheets of ice missed the northeast corner of the state, leaving the land along the Driftless Area Byway rugged and hilly with rock outcroppings, springs and cold water trout streams. Rivers coursed their way through the land, carving deep furrows in some places and leaving gently rolling hills in others. In western Iowa, wind has shaped fine sand into the impressive Loess Hills, a rare land form found in only one other place on earth. Iowa’s two national scenic byways and nine state byways offer unique varieties of scenic features, and more for you to see and do. View three states from atop a Mississippi River bluff, stop at a modern art museum and then tour a working farm. Explore a historic mill, visit a national aquarium, take a boat ride in a cave, purchase locally crafted pottery and wares from local artisans or trace the footsteps of Lewis and Clark. Experience the actual wagon ruts of the Mormon Trail, ride your bike 13 stories high, canoe a water trail, star gaze under Iowa’s darkest sky, and marvel at mounds built by prehistoric cultures. Agriculture wraps Iowa’s byways with an abundance of farmland vistas and fills Iowa lands with ever-changing crops and activities for you to “harvest.” You’ll see croplands on the vast flat plains and farmsteads sprinkled across rolling hills reminiscent of a Grant Wood painting. Along the way, you might wander in a corn maze, rest at a bed and breakfast, study farming in museums, discover the Iowa barn quilt collection or visit a working Amish farm. When you are ready to step outside your vehicle, you’ll find much more to do and see. Prairie, forests, rivers and public lands are abundant along Iowa’s byways; providing opportunities for you to stop and play in the outdoors with hiking, biking, kayaking and trout fishing. Classic hometowns with pride for their unique lore and offerings are found all along the byways. They invite you to taste local food, enjoy their architecture, and immerse yourself in the rich history and culture that defines them. Why not plan your next journey off the beaten path? No matter how you choose to make the most of every moment, we know that time spent along Iowa’s byways is sure to grow your love for Iowa’s diverse, beautiful vistas and authentic communities. Happy driving!

Benefits of endoscopic vein harvesting.

The purpose of this study was to evaluate and compare the benefits of endoscopic saphenous vein harvesting (EVH) with the traditional incision technique (TIT) for coronary artery bypass grafting (CABG) in respect to the technical procedure and clinical outcome. In a prospective nonrandomized, case-matched study the greater saphenous vein was harvested for CABG in 22 patients using the endoscopic technique and in 18 patients with the traditional method. Comparisons were made for the operating time, length of incision and vein harvested, graft quality, postoperative complications, and pain assessment. Patient demographics were well matched. EVH required smaller incisions than did the TIT (10.5 +/- 6.6 vs. 31.2 +/- 7.8 cm, respectively; p < 0.0001). Harvest time and vein quality were comparable in the two groups. Total vein operating time was shorter following the endoscopic technique (60 +/- 24 vs. 100 +/- 35 minutes, respectively; p < 0.0001). EVH had fewer complications (NS), and postoperative pain was significantly less (p = 0.0034). The major advantages of endoscopic vein harvesting are a significant reduction of postoperative pain and strikingly better cosmetic results. Wound complications seem to be less frequent.

Biblioteca digital: a experiência do Impa

Relato da experiência do Impa na informatização de sua biblioteca, utilizando o software Horizon, e na construção de um servidor de preprints (dissertações de mestrado, teses de doutorado e artigos ainda não publicados) através da participação no projeto internacional Math-Net.

Pieces of Iowa’s Past, March 28, 2012

Pieces of Iowa’s Past, published by the Iowa State Capitol Tour Guides weekly during the legislative session, features historical facts about Iowa, the Capitol, and the early workings of state government. All historical publications are reproduced here with the actual spelling, punctuation, and grammar retained. THIS WEEK: Electric Lighting in the Iowa State Capitol BACKGROUND: REPORT OF COMMITTEE ON LIGHTING THE BUILDING AND GROUNDS WITH ELECTRICITY—1882 The Capitol Commissioners submitted biennial reports throughout the 15 years it took to build the Capitol (1871-1886). Often there were committees formed to investigate a certain phase of the construction. The following is the report of the Committee on Lighting. Note: The Capitol Commissioners determined the gas lighting to be the best choice in the 1880s. Less than 20 years later, the process began to convert the Capitol from gas to electric lighting. There was a period where both types of lighting were being used in the Capitol. The photograph of the 1904 apple harvest shows both electric and gas fixtures. The turn of the 20th century photograph of the library also shows chandeliers utilizing both gas and electricity. The photograph of the single fixture in the library is a mystery. It shows a fixture utilizing both gas and electricity, but no other photographs of the library exist where this fixture appears. Perhaps it was a prototype and never used in the Capitol.

A detailed urinary excretion time course study of captan and folpet biomarkers in workers for the estimation of dose, main route-of-entry and most appropriate sampling and analysis strategies

Captan and folpet are two fungicides largely used in agriculture, but biomonitoring data are mostly limited to measurements of captan metabolite concentrations in spot urine samples of workers, which complicate interpretation of results in terms of internal dose estimation, daily variations according to tasks performed, and most plausible routes of exposure. This study aimed at performing repeated biological measurements of exposure to captan and folpet in field workers (i) to better assess internal dose along with main routes-of-entry according to tasks and (ii) to establish most appropriate sampling and analysis strategies. The detailed urinary excretion time courses of specific and non-specific biomarkers of exposure to captan and folpet were established in tree farmers (n = 2) and grape growers (n = 3) over a typical workweek (seven consecutive days), including spraying and harvest activities. The impact of the expression of urinary measurements [excretion rate values adjusted or not for creatinine or cumulative amounts over given time periods (8, 12, and 24 h)] was evaluated. Absorbed doses and main routes-of-entry were then estimated from the 24-h cumulative urinary amounts through the use of a kinetic model. The time courses showed that exposure levels were higher during spraying than harvest activities. Model simulations also suggest a limited absorption in the studied workers and an exposure mostly through the dermal route. It further pointed out the advantage of expressing biomarker values in terms of body weight-adjusted amounts in repeated 24-h urine collections as compared to concentrations or excretion rates in spot samples, without the necessity for creatinine corrections.

Development of Elispot and CFSE flow cytometric assays for detecting beryllium sensitivity

Background: Beryllium sensitization (BeS) is caused by exposure to beryllium in the workplace and may progress to chronic beryllium disease (CBD). This granulomatous lung disorder mimicks sarcoidosis clinically, but is characterized by beryllium specific CD4+ T-cells immune response. BeS is classically detected by beryllium lymphocyte proliferation test (BeLPT), but this assay requires radioactivity and is not very sensitive. In the context of a study aiming to evaluate if CBD patients are misdiagnosed as sarcoidosis patients in Switzerland, we developed EliSpot and CFSE beryllium flow cytometric test. Methods: 23 patients considered as having sarcoidosis (n = 21), CBD (n = 1) and possible CBD (n = 1) were enrolled. Elispot was performed using plate covered with gamma-IFN mAb. Cells were added to wells and incubated overnight at 37 °C with medium (neg ctrl), SEB (pos ctrl) or BeSO4 at 1, 10 and 100 microM. Anti-IFN-gamma biotinylated mAb were added and spots were visualized using streptavidinhorseradish peroxidase and AEC substrate reagent. Results were reported as spot forming unit (SFU). For Beryllium specific CFSE flow cytometry analysis, CFSE labelled cells were cultured in the presence of SEB and 1, 10 or 100 microM BeSO4. Unstimulated CFSE labeled cells were defined as controls. The cells were incubated for 6 days at 37 °C and 5% CO2. Surface labelling of T-lymphocytes and vivid as control of cells viability was performed at the time of harvest. Results: Using EliSpot technology, we were able to detect a BeS in 1/23 enrolled patients with a mean of 780 SFU (cut off value at 50 SFU). This positive result was confirmed using different concentration of BeSO4. Among the 23 patients tested, 22 showed negative results with EliSpot. Using CFSE flow cytometry, 1/7 tested patients showed a positive result with a beryllium specific CD4+ count around 30% versus 45% for SEB stimulation as positif control and 0.6 % for negative control. This patient was the one with a positive EliSpot assay. Conclusions: The preliminary data demonstrated the feasibility of Elispot and CFSE flow cytometry to detect BeS. The patient with a beryllium specific positive EliSpot and CFSE flow cytometry result had been exposed to beryllium at her workplace 20 years ago and is still regularly controlled for her pulmonary status. A positive BeLPT had already been described in 2001 in France for this patient. Further validation of these techniques are in progress.

Characterization of Fly Ash for Use in Concrete, HR-225, 1983

Recent construction of new generation power plants burning western coal within Iowa has resulted in fly Ash production on the order of 760,000 tons annually. Although fly ash has long been accepted as a valuable replacement for portland cement in concrete, most experience has been with fly ash generated from eastern bituminous coals. A few years ago, fly ash in Iowa was not a significant factor because production was small and economics dictated disposal as the better alternative than construction use. Today, the economic climate, coupled with abundance of the material, makes constructive use in concrete feasible. The problem is, however, fly ash produced from new power plants is different than that for which information was available. It seems fly ash types have outgrown existing standards. The objective of this study was to develop fundamental information about fly ashes available to construction in Iowa such that its advantages and limitations as replacement to portland cement can be defined. Evaluative techniques used in this work involve sophisticated laboratory equipment, not readily available to potential fly ash users, so a second goal was preliminary development of rapid diagnostic tests founded on fundamental information. Lastly, Iowa Department of Transportation research indicated an interesting interdependency among coarse aggregate type, fly ash and concrete's resistance to freeze-thaw action. Thus a third charge of this research project was to verify and determine the cause for the phenomena. One objective of this project was to determine properties of Iowa fly ashes and evaluate their relevance to use of the material as an admixture of PCC. This phase of the research involved two approaches. The first involved the development of a rapid method for determining quantitative elemental composition while the second was aimed at both qualitative and quantitative determination of compounds. X-ray fluorescence techniques were adapted for rapid determination of elemental composition of fly ash. The analysis was performed using a Siemens SR-200 sequential x-ray spectrometer controlled by a PDP-11-03 microcomputer. The spectrometer was equipped with a ten sample specimen chamber and four interchangeable analyzing crystals. Unfiltered excitation radiation was generated using a chromium tube at 50 KV and 48 ma. Programs for the spectrometer were developed by the Siemens Corporation.