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The objective was to evaluate the agronomic performance of black wattle seedlings (Acacia mearnsii) grown on substrates with increasing proportions of biochar based on anaerobic sewage sludge (ASS-biochar). In addition, the present study proposed appropriate ranges for the main physical-hydraulic and chemical attributes of these substrates. Made available in DSpace on 2022-03-10T02:03:53Z (GMT). No. of bitstreams: 1 Artigo-Agronomic-performance-and-optimal-ranges.pdf: 1807745 bytes, checksum: 88e79f479691a66dfe768a2557af74e2 (MD5) Previous issue date: 2021 Published online: 21 August 2021.

Efficient water use in agriculture is a global demand, and in this context, the implementation of a sprinkler irrigated rice system has become a reality. Besides saving water, proper management of a sprinkler irrigated system can maintain high levels of productivity. This study aimed to determine the effect of soil water tension on rice crop production, in both vegetative and reproductive stages, as well as to evaluate the effect of soil water availability and physicochemical attributes on biometric and reproductive characteristics associated to rice grain yield under sprinkler irrigation. The experiment was carried out at the Lowland Experimental Station, Embrapa Clima Temperado, Capão do Leão ? Rio Grande do Sul, Brazil, during two growing seasons, in an area irrigated by a lateral-move sprinkler irrigation system. The following irrigation managements were evaluated: irrigation, when the mean soil water tension was i) 10?kPa; ii) 20?kPa; iii) 40?kPa; iv) 40?kPa on vegetative and 20?kPa on reproductive stages and v) 40?kPa on vegetative and 10?kPa on reproductive stages. Under sprinkler irrigation, rice plant development was impaired as soil water tension increased, evidenced by a reduction in plant heights. Soil water tension of 10?kPa was adequate to manage the sprinkler irrigation in rice, especially in the reproductive stage and when using cultivars developed for flooded environments. Rice development and yield were affected by increasing soil bulk density and acidity. Rainwater represented approximately 40 % of the water used by sprinkler irrigated rice during the crop cycle, contributing with the reduction of irrigation water use. Made available in DSpace on 2020-12-02T09:07:05Z (GMT). No. of bitstreams: 1 Pinto-etal-2020.pdf: 567113 bytes, checksum: b82ff96fafd1b2026d3b539a67485f7c (MD5) Previous issue date: 2020

The aim of this study was to determine the impact of harvesting traffic by evaluating the spatial variability of soil physical attributes on a clayey Oxisol under sugarcane cultivation using different row spacing. Two areas of sugarcane production (RB855156 genotype) were planted in autumn 2013, both using conventional planting systems. Treatments were either sugarcane cultivated using: (i) single-row spacing (SR) of 1.50 m; or (ii) double-row spacing (DR) of 0.40 × 1.50 m. Areas using SR spacing occupied a total of 6 ha areas using DR spacing occupied a total of 2 ha. Assessments of soil physical attributes were performed during the summer of 2016 after the second harvest. Soil measurements in each area were done at 100 points using a grid design with dimensions of 10 m long by 5 m wide. Soil sampling was taken from the 0.00-0.10 m layer, from points distributed along the planted row and the machine?s wheel track. The following soil physical attributes were assessed: bulk density, total porosity, macroporosity, microporosity, soil penetration resistance, and water contentat field capacity. Bd and PR in the single-row spacing showed critical values for adequate sugarcane root development. The highest spatial variability of PR and Ma was found in double-row spacing, however, this spacing arrangement promoted a better soil physical conditions. Made available in DSpace on 2020-12-22T09:03:42Z (GMT). No. of bitstreams: 1 Panzieira-et-al.2020.pdf: 1390910 bytes, checksum: fdac74b0945a53bba592ce1add243526 (MD5) Previous issue date: 2020

O objetivo foi avaliar as propriedades físico-hídricas de diferentes substratos e seus efeitos no desenvolvimento de mudas de alface em sistema floating. O estudo foi realizado em casa de vegetação durante os meses de janeiro e fevereiro de 2017. O delineamento foi de blocos casualizados, com 16 tratamentos, representandos por 13 proporções de substratos à base de composto orgânico, casca de arroz carbonizada e vermiculita e três substratos comerciais. Foram avaliadas as características físico-hídricas (fração granulométrica, densidade seca, porosidade total, espaço de aeração, água facilmente disponível, água disponível, água remanescente e capacidade de retenção de água), pH e condutividade elétrica dos substratos. O número de folhas, altura das plantas, comprimento do sistema radicular, massa fresca de raiz e parte aérea e massa seca de raiz e parte aérea foram avaliados aos 25 dias após a emergência. O espaço de aeração e a água remanescente são as variáveis físico-hídricas aprioritárias que devem ser avaliadas em substratos que serão utilizados em sistema floating. As formulações com 33,33% de composto orgânico, 43,33 a 53,33% de casca de arroz carbonizada, e 23,33 a 13,33% de vermiculita apresentaram os melhores desempenhos entre os substratos estudados para a produção de mudas de alface em sistema floating. Made available in DSpace on 2020-12-10T09:04:42Z (GMT). No. of bitstreams: 1 3937-Texto-do-artigo-17081-1-10-20201106.pdf: 548763 bytes, checksum: 07423ede9c51e21f99faedb1b58ba5e3 (MD5) Previous issue date: 2020

Avaliou-se o efeito da retenção de água de substratos para plantas formulados a partir de diferentes proporções de lodo de esgoto (LETE) solarizado, na produção de mudas de acácia-negra (Acacia mearnsii). O experimento foi conduzido em casa de vegetação e no Laboratório de Física do Solo da Embrapa Clima Temperado. O LETE utilizado foi coletado em leitos de secagem de uma Estação de Tratamento de Esgoto aeróbio de Rio Grande - RS. Os tratamentos consistiram de cinco doses de LETE solarizado, combinadas com cinza de casca de arroz e vermiculita em diferentes proporções (20:40:40, 30:35:35, 40:30:30, 50:25:25 e 60:20:20) e dois substratos comerciais (Beifort® S10 B e Mec Plant®). O delineamento experimental foi de blocos casualizados. Foram avaliadas as características físico-hídricas: água facilmente disponível, água tamponante, água remanescente e capacidade de retenção de água. As variáveis de crescimento avaliadas foram: massa fresca da parte aérea e do sistema radicular. O substrato com 20% de LETE solarizado, 40% vermiculita e 40% cinza de casca de arroz apresentou a melhor condição físico-hídrica para o desenvolvimento de mudas de acácia-negra. Made available in DSpace on 2019-12-13T18:11:28Z (GMT). No. of bitstreams: 1 2019BambergCienciaRural.pdf: 540161 bytes, checksum: ff96713c084d9f2247defbd0d9ce1a51 (MD5) Previous issue date: 2019

Made available in DSpace on 2019-12-30T18:10:48Z (GMT). No. of bitstreams: 1 SeminaCiAgMittelmannProduction.pdf: 363245 bytes, checksum: 39152185b5b3d0a8133d04e3c3e2af64 (MD5) Previous issue date: 2019

Made available in DSpace on 2019-11-27T00:40:12Z (GMT). No. of bitstreams: 1 CarlosReisserAlex3707Textodoartigo1563811020191126.pdf: 925338 bytes, checksum: 32af2144e06cca6d5170ccbb2df0cb3b (MD5) Previous issue date: 2019

The atomic and magnetic structures of CoO and NiO have been probed using reverse Monte Carlo refinements of neutron total scattering data. The results obtained show that the known magnetic structure for NiO can be recovered by the reverse Monte Carlo process starting from random spin configurations, but it is insensitive to the spin direction in the {111} ferromagnetic planes. Refinements of the magnetic structure of CoO starting from random spin configurations result in collinear or non-collinear magnetic structure, consistent with those reported by other techniques. Starting from an ordered collinear spin structure for CoO and NiO leads to different results than when starting from a random arrangement of spins, evidence for configurational bias that highlights the need to take care when selecting a starting model for reverse Monte Carlo refinements of magnetic structures.

Introduction: Peritonsillar abscess (PTA) is the most common deep neck infection. Several draining methods are accepted, including needle aspiration (NA), incision and drainage (ID) and abscesstonsillectomy. Despite decades of experience with each technique a gold standard for the management of PTA [for full text, please go to the a.m. URL], 87th Annual Meeting of the German Society of Oto-Rhino-Laryngology, Head and Neck Surgery

Background— Compared with fluoroscopy, the current imaging standard of care for guidance of electrophysiology procedures, magnetic resonance imaging (MRI) provides improved soft-tissue resolution and eliminates radiation exposure. However, because of inherent magnetic forces and electromagnetic interference, the MRI environment poses challenges for electrophysiology procedures. In this study, we sought to test the feasibility of performing electrophysiology studies with real-time MRI guidance. Methods and Results— An MRI-compatible electrophysiology system was developed. Catheters were targeted to the right atrium, His bundle, and right ventricle of 10 mongrel dogs (23 to 32 kg) via a 1.5-T MRI system using rapidly acquired fast gradient-echo images (≈5 frames per second). Catheters were successfully positioned at the right atrial, His bundle, and right ventricular target sites of all animals. Comprehensive electrophysiology studies with recording of intracardiac electrograms and atrial and ventricular pacing were performed. Postprocedural pathological evaluation revealed no evidence of thermal injury to the myocardium. After proof of safety in animal studies, limited real-time MRI-guided catheter mapping studies were performed in 2 patients. Adequate target catheter localization was confirmed via recording of intracardiac electrograms in both patients. Conclusions— To the best of our knowledge, this is the first study to report the feasibility of real-time MRI-guided electrophysiology procedures. This technique may eliminate patient and staff radiation exposure and improve real-time soft tissue resolution for procedural guidance.

O objetivo deste trabalho foi determinar a influência da tensão de água e de atributos físicos e químicos do solo sobre a produtividade do arroz irrigado por aspersão, em terras baixas no Rio Grande do S l. Na safra 2011/2012, foram avaliados os efeitos das tensões de água no solo de 20 e 40 kPa, durante todo o ciclo da cultura, bem como as de 40 e 20 kPa nas fases vegetativa e reprodutiva, respectivamente. Na safra 2012/2013, foram avaliadas as tensões de 10, 20 e 40 kPa, durante todo o ciclo da cultura, e as de 40 e 10 kPa nas fases vegetativa e reprodutiva, respectivamente. Em ambas as safras, utilizou-se a cultivar de arroz irrigado BRS Pampa. O gasto com água na irrigação por aspersão representou 48% do gasto com a irrigação por inundação. A produtividade do arroz correlacionou-se positivamente com a microporosidade e com os teores de fósforo e potássio disponíveis no solo; e negativamente com a macroporosidade e a saturação por alumínio. A avaliação conjunta da tensão de água e de atributos físicos e químicos do solo permite avaliar com mais propriedade a variabilidade na produtividade de arroz irrigado por aspersão em terras baixas no Rio Grande do Sul. A irrigação por aspersão possibilita melhor uso da água proveniente da precipitação pluvial, com efeitos positivos sobre a economia de água. Made available in DSpace on 2017-04-12T12:47:14Z (GMT). No. of bitstreams: 1 WalkyriaProdutividadedearrozirrigado.pdf: 648665 bytes, checksum: 6219a06dc97fd5958f4a718d5d34e471 (MD5) Previous issue date: 2017-04-12

Background— Magnetic resonance imaging (MRI) is an important diagnostic modality currently unavailable for millions of patients because of the presence of implantable cardiac devices. We sought to evaluate the diagnostic utility and safety of noncardiac and cardiac MRI at 1.5T using a protocol that incorporates device selection and programming and limits the estimated specific absorption rate of MRI sequences. Methods and Results— Patients with no imaging alternative and with devices shown to be MRI safe by in vitro phantom and in vivo animal testing were enrolled. Of 55 patients who underwent 68 MRI studies, 31 had a pacemaker, and 24 had an implantable defibrillator. Pacing mode was changed to “asynchronous” for pacemaker-dependent patients and to “demand” for others. Magnet response and tachyarrhythmia functions were disabled. Blood pressure, ECG, oximetry, and symptoms were monitored. Efforts were made to limit the system-estimated whole-body average specific absorption rate to 2.0 W/kg (successful in >99% of sequences) while maintaining the diagnostic capability of MRI. No episodes of inappropriate inhibition or activation of pacing were observed. There were no significant differences between baseline and immediate or long-term (median 99 days after MRI) sensing amplitudes, lead impedances, or pacing thresholds. Diagnostic questions were answered in 100% of nonthoracic and 93% of thoracic studies. Clinical findings included diagnosis of vascular abnormalities (9 patients), diagnosis or staging of malignancy (9 patients), and assessment of cardiac viability (13 patients). Conclusions— Given appropriate precautions, noncardiac and cardiac MRI can potentially be safely performed in patients with selected implantable pacemaker and defibrillator systems.

Background— Patients with left ventricular dysfunction have an elevated risk of sudden cardiac death. However, the substrate for ventricular arrhythmia in patients with nonischemic cardiomyopathy remains poorly understood. We hypothesized that the distribution of scar identified by MRI is predictive of inducible ventricular tachycardia. Methods and Results— Short-axis cine steady-state free-precession and postcontrast inversion-recovery gradient-echo MRI sequences were obtained before electrophysiological study in 26 patients with nonischemic cardiomyopathy. Left ventricular ejection fraction was measured from end-diastolic and end-systolic cine images. The transmural extent of scar as a percentage of wall thickness (percent scar transmurality) in each of 12 radial sectors per slice was calculated in all myocardial slices. The percentages of sectors with 1% to 25%, 26% to 50%, 51% to 75%, and 76% to 100% scar transmurality were determined for each patient. Predominance of scar distribution involving 26% to 75% of wall thickness was significantly predictive of inducible ventricular tachycardia and remained independently predictive in the multivariable model after adjustment for left ventricular ejection fraction (odds ratio, 9.125; P =0.020). Conclusions— MR assessment of scar distribution can identify the substrate for inducible ventricular tachycardia and may identify high-risk patients with nonischemic cardiomyopathy currently missed by ejection fraction criteria.

Many glaciers along the southeast and northwest coast of Greenland have accelerated, increasing the Greenland ice sheet's (GrIS) contribution to global sea-level rise. Here, we map elevation changes in northwest Greenland during 2003-2009 using high-resolution Ice, Cloud and land Elevation Satellite (ICESat) laser altimeter data (Zwally, 2010) supplemented with altimeter surveys from NASA's Airborne Topographic Mapper (ATM) during 2002-2011 (Krabill, 2011). We use the measurements of elevation change to estimate catchment-wide ice volume loss (convert is to mass loss) and compare with independent measurements from GPS and the Gravity Recovery and Climate Experiment (GRACE) satellite gravity mission, launched in March, 2002. The GRACE results provide a direct measure of mass loss averaged over the entire northwest sector, while the GPS data are used to monitor crustal uplift caused by ice mass loss close to the sites. GPS data from a long term site at Thule Airbase show accelerated uplift starting in 2005 and a minor deceleration in 2009-2010. The deceleration is more dominant at GPS stations deployed in 2007 in northwest Greenland as part of the Greenland GPS Network (GNET). Independently, all three methods suggest increased ice loss in northwest Greenland starting in 2005 and a slowdown in 2009-2010.

This business case study is designed for MBA courses in Organizational Behavior, Organization Change and Negotiations. The case follows a young middle manager who has very little formal authority as she attempts to implement a new project staffing system for engineers in a high-tech matrix organization. As the company rapidly grows, she experiences significant resistance to change from section leaders, program managers and engineers who have become accustomed to competitive behavior in an environment rich with opportunities. However, as the company experiences retrenchment during the economic downturn of 2009, the change resistance continues, but within an environment where there is a paucity of projects. The case shows how Sophie grows as a middle manager and learns the necessary skills to be successful at managing change and “influencing without authority”.