Nitrogênio, carbono e atividade da biomassa microbiana do solo em plantações de eucalipto

Grande parte das plantações de eucalipto no Brasil situa-se em solos de baixa fertilidade, para os quais a técnica de fertilização e o processo de ciclagem de nutrientes são fundamentais para elevar e manter a produção florestal. Os ganhos de produtividade dessas plantações em resposta à aplicação de N têm sido relativamente baixos, o que indica que o solo tem sido capaz de suprir boa parte da demanda deste nutriente para as plantas. O N da biomassa microbiana é tido como uma fração facilmente disponível, mas pouco se sabe sobre como fatores bióticos e abióticos afetam a sua dinâmica em plantações de eucalipto no Brasil. Desse modo, o objetivo deste trabalho foi avaliar a variação do N (NBM) e C (CBM) da biomassa microbiana do solo e de outras características com elas relacionadas em plantações de eucalipto com sete anos de idade, cultivadas em várias condições edafoclimáticas do sudeste brasileiro. Amostragens do solo foram realizadas durante quatro épocas, de março a novembro de 1995. O teor de NBM variou de 9,17 a 103,71 µg g-1 solo, sendo significativamente influenciado pela época de amostragem. Essa variação foi explicada pela combinação da precipitação pluviométrica com o teor de C orgânico ou N total. O teor de argila dos solos estudados foi outra característica de grande importância nessa variação. Dentre outras características avaliadas, verificou-se que a forma de N mineral predominante foi N-NH4+ e que os teores de C orgânico e do CBM (carbono da biomassa microbiana) variaram de 2,78 a 12,32 g kg-1 e de 43,39 a 401,06 µg g-1 solo, respectivamente. A RA (respiração acumulada do solo) foi de 14,57 a 79,42 µg g-1 solo e o qCO2 (quociente metabólico) de 862 a 8026 µg g-1 h-1 . O CBM foi também afetado significativamente pela época de amostragem, ao contrário dos teores de C orgânico e N total. As regressões lineares simples do teor de N-NO3-, C orgânico, N total, CBM e NBM com o teor de argila permitiram um modelo preditivo que explicasse a variação destes atributos nos diferentes municípios. A umidade atual do solo explicou 87% da variação dos teores de N-NO3- e de N total; em torno de 71% do C orgânico e de 48 e 55% da variação do CBM e NBM, respectivamente. As regressões simples do N-NO3- com o CBM ou NBM apresentaram baixa capacidade preditiva, porém, quando conjugadas com os teores de C orgânico ou N total, por meio de regressão linear múltipla, aumentaram a capacidade preditiva da mineralização do N.

[Lettre autographe signée de Giuseppe Verdi adressée à Escudier, (17 avril 1872)]

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Federal Highway Administration Finding of No Significant Impact Collins Road NE (Highway 100) Cedar Rapids, Linn County, Iowa, December 17, 2009

The proposed project consists of improving approximately 2.6 miles of Collins Road NE (Highway 100) in Cedar Rapids, Iowa. The project extends from the intersection of Center Point Road to approximately 750 feet east of its intersection with 1st Avenue.

Report on a review of selected general and application controls over the Iowa Department of Human Services’ Issuance Verification System for the period March 19, 2009 through April 17, 2009

Report on a review of selected general and application controls over the Iowa Department of Human Services’ Issuance Verification System for the period March 19, 2009 through April 17, 2009

Secure and Prepared Newsletter, June 17, 2010, Vol. 6, no. 12

A bi-weekly newsletter for those involved in the fields of homeland security and/or emergency management

Cetuximab in combination with chemoradiotherapy prior to surgery in patients with resectable, locally advanced esophageal carcinoma : a prospective, multicenter phase lb-ll trial of the Swiss Group for Clinical Cancer Research (SAKK 75/06) : 4570

Background: Cetuximab significantly enhances efficacy of radiotherapy and chemotherapy in head and neck cancer. We investigated the safety and feasibility of adding cetuximab to neoadjuvant chemoradiation of locally advanced esophageal cancer. Methods: Pts with resectable, locally advanced squamous cell carcinoma (SCC) or adenocarcinoma (AC) of the thoracic esophagus or gastroesophageal junction (staged by EUS, CT and PET scan) were treated with 2 cycles of induction chemotherapy (docetaxel 75mg/m2, cisplatin 75mg/m2 q3w and weekly cetuximab 250mg/m2), followed by concomitant chemo- immuno-radiation therapy (CIRT: docetaxel 20mg/m2, cisplatin 25mg/m2 and cetuximab 250mg/m2 weekly five times concomitant with 45 Gy radiotherapy in 25 fractions); followed by surgery 4-8 weeks later. The phase I part consisted of 2 cohorts of 7 patients each, without and with docetaxel during CIRT, respectively. Interpatient dose-escalation (adding docetaxel during CIRT) was possible if < 2 out of 7 pts of the 1st cohort experienced limiting toxicity. Having finished the phase 1 part, 13 additional patients were treated with docetaxel-containing CIRT in a phase II part. Pathological response was evaluated according to the Mandard classification. Results: 27 pts from 12 institutions were included. As of today, results from 20 pts are available (cohort 1: 7, cohort 2: 7, phase ll : 6). Median age was 64yrs (range 47-71). 11 AC; 9 SCC. 19 pts (95%) completed CIRT (1 pt stopped treatment during induction therapy due to sepsis). 17 pts underwent resection (no surgery: 1pt for PD, 1pt for cardiac reasons). Grade 3 toxicities during CIRT included anorexia 15%, dysphagia/esophagitis 15%, fatigue 10%, nausea 10%, pruritus 5%, dehydration 5%, nail changes 5% and rash 5% .1 pt suffered from pulmonary embolism. 13 pts (65%, intention-to-treat) showed a complete or near complete pathological remission (cohort 1: 5, cohort 2: 4, phase II: 4). Conclusions: Adding cetuximab to preoperative chemoradiation for esophageal cancer is safe and feasible in a community-based multicenter setting. Antineoplastic activity is encouraging with 65% pathological responders.

Iowa Workforce Monthly, June-July 2010, Issue 17

Highlights: * Iowa Workforce Development Director Elisabeth Buck and Deputy Director Joe Walsh recently visited a number of IowaWORKS offices in Eastern Iowa as part of a summer tour........................................pg. 2 * Amber Connolly was recently awarded the Iowa Association of Workplace Professionals (IAWP) individual award for Outstanding Specialized Customer Service...............pg. 2 * Iowa Workforce Development has partnered with Iowa’s Community Colleges to implement Iowa’s National Career Readiness Certificate (NCRC).................pg. 3 * O*NET is an occupational information network developed under the sponsorship of the U.S. Department of Labor/Employment and Training Administration.....................pg. 3