bluuebunny/crossref_metadata_2025 huggingface dataset:
Local Category-Specific Gamma Band Responses in the Visual Cortex Do Not Reflect Conscious Perception
Authors: Aru Jaan , Axmacher Nikolai , Do Lam Anne T. A. , Fell Juergen , Elger Christian E. , Singer Wolf , Melloni Lucia
Published: October 2012

Which neural processes underlie our conscious experience? One theoretical view argues that the neural correlates of consciousness (NCC) reside in local activity in sensory cortices. Accordingly, local category-specific gamma band responses in visual cortex correlate with conscious perception. However, as most studies manipulated conscious perception by altering the amount of sensory evidence, it is possible that they reflect prerequisites or consequences of consciousness rather than the actual NCC. Here we directly address this issue by developing a new experimental paradigm in which conscious perception is modulated either by sensory evidence or by previous exposure of the images while recording intracranial EEG from the higher-order visual cortex of human epilepsy patients. A clear prediction is that neural processes directly reflecting conscious perception should be present regardless of how it comes about. In contrast, we observed that although subjective reports were modulated both by sensory evidence and by previous exposure, gamma band responses solely reflected sensory evidence. This result contradicts the proposal that local gamma band responses in the higher-order visual cortex reflect conscious perception.
Mammalian Target of Rapamycin Signaling Is a Key Regulator of the Transit-Amplifying Progenitor Pool in the Adult and Aging Forebrain
Authors: Paliouras Grigorios N. , Hamilton Laura K. , Aumont Anne , Joppé Sandra E. , Barnabé-Heider Fanie , Fernandes Karl J. L.
Published: October 2012

Adult forebrain neurogenesis is dynamically regulated. Multiple families of niche-derived cues have been implicated in this regulation, but the precise roles of key intracellular signaling pathways remain vaguely defined. Here, we show that mammalian target of rapamycin (mTOR) signaling is pivotal in determining proliferation versus quiescence in the adult forebrain neural stem cell (NSC) niche. Within this niche, mTOR complex-1 (mTORC1) activation displays stage specificity, occurring in transiently amplifying (TA) progenitor cells but not in GFAP+ stem cells. Inhibiting mTORC1 depletes the TA progenitor poolin vivoand suppresses epidermal growth factor (EGF)-induced proliferation within neurosphere cultures. Interestingly, mTORC1 inhibition induces a quiescence-like phenotype that is reversible. Likewise, mTORC1 activity and progenitor proliferation decline within the quiescent NSC niche of the aging brain, while EGF administration reactivates the quiescent niche in an mTORC1-dependent manner. These findings establish fundamental links between mTOR signaling, proliferation, and aging-associated quiescence in the adult forebrain NSC niche.
Electrical Stimulation of Human Fusiform Face-Selective Regions Distorts Face Perception
Authors: Parvizi Josef , Jacques Corentin , Foster Brett L. , Withoft Nathan , Rangarajan Vinitha , Weiner Kevin S. , Grill-Spector Kalanit
Published: October 2012

Face-selective neural responses in the human fusiform gyrus have been widely examined. However, their causal role in human face perception is largely unknown. Here, we used a multimodal approach of electrocorticography (ECoG), high-resolution functional magnetic resonance imaging (fMRI), and electrical brain stimulation (EBS) to directly investigate the causal role of face-selective neural responses of the fusiform gyrus (FG) in face perception in a patient implanted with subdural electrodes in the right inferior temporal lobe. High-resolution fMRI identified two distinct FG face-selective regions [mFus-faces and pFus-faces (mid and posterior fusiform, respectively)]. ECoG revealed a striking anatomical and functional correspondence with fMRI data where a pair of face-selective electrodes, positioned 1 cm apart, overlapped mFus-faces and pFus-faces, respectively. Moreover, electrical charge delivered to this pair of electrodes induced a profound face-specific perceptual distortion during viewing of real faces. Specifically, the subject reported a “metamorphosed” appearance of faces of people in the room. Several controls illustrate the specificity of the effect to the perception of faces. EBS of mFus-faces and pFus-faces neither produced a significant deficit in naming pictures of famous faces on the computer, nor did it affect the appearance of nonface objects. Further, the appearance of faces remained unaffected during both sham stimulation and stimulation of a pair of nearby electrodes that were not face-selective. Overall, our findings reveal a striking convergence of fMRI, ECoG, and EBS, which together offer a rare causal link between functional subsets of the human FG network and face perception.
Ventral Tegmental Area Glutamate Neurons: Electrophysiological Properties and Projections
Authors: Hnasko Thomas S. , Hjelmstad Gregory O. , Fields Howard L. , Edwards Robert H.
Published: October 2012

The ventral tegmental area (VTA) has a central role in the neural processes that underlie motivation and behavioral reinforcement. Although thought to contain only dopamine and GABA neurons, the VTA also includes a recently discovered population of glutamate neurons identified through the expression of the vesicular glutamate transporter VGLUT2. A subset of VGLUT2+VTA neurons corelease dopamine with glutamate at terminals in the NAc, but others do not express dopaminergic markers and remain poorly characterized. Using transgenic mice that express fluorescent proteins in distinct cell populations, we now find that both dopamine and glutamate neurons in the medial VTA exhibit a smaller hyperpolarization-activated current (Ih) than more lateral dopamine neurons and less consistent inhibition by dopamine D2receptor agonists. In addition, VGLUT2+VTA neurons project to the nucleus accumbens (NAc), lateral habenula, ventral pallidum (VP), and amygdala. Optical stimulation of VGLUT2+projections expressing channelrhodopsin-2 further reveals functional excitatory synapses in the VP as well as the NAc. Thus, glutamate neurons form a physiologically and anatomically distinct subpopulation of VTA projection neurons.
Thyroid function and the metabolic syndrome in older persons: a population-based study
Authors: Heima Nathalie E , Eekhoff E Marelise W , Oosterwerff Mirjam M , Lips Paul T A , van Schoor Natasja M , Simsek Suat
Published: October 2012

Background

Studies suggest an association between a high TSH and (individual components of) the metabolic syndrome. Only a few studies have been performed in the general older population.

Objective

This study investigates the association between serum TSH and the metabolic syndrome in a representative sample of older persons in The Netherlands.

Design and patients

Data of the Longitudinal Aging Study Amsterdam were used, which is an ongoing cohort study in a representative sample of Dutch older persons. A total of 1187 subjects (590 men and 597 women) between the ages of 65 and 88 years participated in the study.

Measurements

Metabolic syndrome (US National Cholesterol Education Program definition) and its individual components were assessed, as well as serum TSH levels.

Results

Among the participants, the prevalence of the metabolic syndrome was 34.2%. The mean serum TSH was 1.9 mU/l. Subjects in the upper quartile with a serum TSH level above 2.28 mU/l (odds ratio (OR)=1.68; 95% confidence interval (CI) 1.19–2.37) had a significantly increased prevalence of metabolic syndrome compared with subjects in the lowest quartile with a serum TSH below 1.04 mU/l. After adjustment for confounders, age, sex, alcohol use, total physical activity, and smoking, the OR was 1.62 (95% CI 1.15–2.32).

Conclusions

Subjects with a serum TSH in the upper quartile have a higher prevalence of metabolic syndrome as compared with subjects with a serum TSH in the lowest quartile.
MECHANISMS IN ENDOCRINOLOGY: Proteomic biomarkers of type 2 diabetes mellitus risk in women with polycystic ovary syndrome
Authors: Galazis Nicolas , Afxentiou Thalia , Xenophontos Mikalena , Diamanti-Kandarakis Evanthia , Atiomo William
Published: October 2012

Women with polycystic ovary syndrome (PCOS) are at increased risk of developing insulin resistance and type 2 diabetes mellitus (T2DM). In this study, we attempted to list the proteomic biomarkers of PCOS and T2DM that have been published in the literature so far. We identified eight common biomarkers that were differentially expressed in both women with PCOS and T2DM when compared with healthy controls. These include pyruvate kinase M1/M2, apolipoprotein A-I, albumin, peroxiredoxin 2, annexin A2, α-1-B-glycoprotein, flotillin-1 and haptoglobin. These biomarkers could help improve our understanding of the links between PCOS and T2DM and could be potentially used to identify subgroups of women with PCOS at increased risk of T2DM. More studies are required to further evaluate the role these biomarkers play in women with PCOS and T2DM.
Thyroid diseases cause mismatch between MIBI scan and neck ultrasound in the diagnosis of hyperfunctioning parathyroids: usefulness of FNA–PTH assay
Authors: Boi Francesco , Lombardo Cira , Cocco Maria Chiara , Piga Mario , Serra Alessandra , Lai Maria Letizia , Calò Pietro Giorgio , Nicolosi Angelo , Mariotti Stefano
Published: October 2012

Design

To evaluate the efficacy of the main tools in the diagnostic localization of hyperfunctioning parathyroids (HP) in primary hyperparathyroidism (pHPT) with concomitant thyroid diseases.

Methods

Forty-three patients with pHPT associated with nodular goiter (NG, n=32) and/or autoimmune thyroid diseases (AITDs, n=11) for a total of 63 neck lesions were considered. Sixteen patients displaying HP (16 lesions), unequivocally localized by sestaMIBI scintigraphy (MIBI) and neck ultrasound (US) (group I), were compared with 27 patients (47 neck lesions) displaying equivocal parathyroid localization (group II). In all cases, neck US, MIBI scan, cytology, and parathyroid hormone assay in fine-needle aspiration washout fluid (FNA–PTH) were performed. All patients finally underwent surgery.

Results

According to histological examination, high FNA–PTH values (>103 pg/ml) correctly identified all HP in both groups of patients (100% of sensitivity and specificity). Both MIBI and US correctly identified all HP only in group I patients; in contrast, four patterns of mismatch between these techniques were observed in group II patients, leading to low diagnostic performances of neck US (71.4% sensitivity and 78.9% specificity) and of MIBI scan (35.7% sensitivity and 42.1% specificity). The latter was due to both false-negative (mainly in AITD) and false-positive (mainly in NG) scan images.

Conclusions

Coexistent thyroid diseases are responsible for mismatch between MIBI and US images resulting in equivocal HP localization. In these cases, FNA–PTH resulted in the most accurate tool to identify HP. However, although safe, it should be advised only to patients with uncertain HP localization.
Angiotensin-converting enzyme 2, angiotensin-(1–7) and Mas: new players of the renin–angiotensin system
Authors: Santos Robson A S , Ferreira Anderson J , Verano-Braga Thiago , Bader Michael
Published: October 2012

Angiotensin (Ang)-(1–7) is now recognized as a biologically active component of the renin–angiotensin system (RAS). Ang-(1–7) appears to play a central role in the RAS because it exerts a vast array of actions, many of them opposite to those attributed to the main effector peptide of the RAS, Ang II. The discovery of the Ang-converting enzyme (ACE) homolog ACE2 brought to light an important metabolic pathway responsible for Ang-(1–7) synthesis. This enzyme can form Ang-(1–7) from Ang II or less efficiently through hydrolysis of Ang I to Ang-(1–9) with subsequent Ang-(1–7) formation by ACE. In addition, it is now well established that the G protein-coupled receptor Mas is a functional binding site for Ang-(1–7). Thus, the axis formed by ACE2/Ang-(1–7)/Mas appears to represent an endogenous counterregulatory pathway within the RAS, the actions of which are in opposition to the vasoconstrictor/proliferative arm of the RAS consisting of ACE, Ang II, and AT1receptor. In this brief review, we will discuss recent findings related to the biological role of the ACE2/Ang-(1–7)/Mas arm in the cardiovascular and renal systems, as well as in metabolism. In addition, we will highlight the potential interactions of Ang-(1–7) and Mas with AT1and AT2receptors.
mTORC1 and mTORC2 regulate insulin secretion through Akt in INS-1 cells
Authors: Le Bacquer Olivier , Queniat Gurvan , Gmyr Valery , Kerr-Conte Julie , Lefebvre Bruno , Pattou François
Published: October 2012

Regulated associated protein of mTOR (Raptor) and rapamycin-insensitive companion of mTOR (rictor) are two proteins that delineate two different mTOR complexes, mTORC1 and mTORC2 respectively. Recent studies demonstrated the role of rictor in the development and function of β-cells. mTORC1 has long been known to impact β-cell function and development. However, most of the studies evaluating its role used either drug treatment (i.e. rapamycin) or modification of expression of proteins known to modulate its activity, and the direct role of raptor in insulin secretion is unclear. In this study, using siRNA, we investigated the role of raptor and rictor in insulin secretion and production in INS-1 cells and the possible cross talk between their respective complexes, mTORC1 and mTORC2. Reduced expression of raptor is associated with increased glucose-stimulated insulin secretion and intracellular insulin content. Downregulation of rictor expression leads to impaired insulin secretion without affecting insulin content and is able to correct the increased insulin secretion mediated by raptor siRNA. Using dominant-negative or constitutively active forms of Akt, we demonstrate that the effect of both raptor and rictor is mediated through alteration of Akt signaling. Our finding shed new light on the mechanism of control of insulin secretion and production by the mTOR, and they provide evidence for antagonistic effect of raptor and rictor on insulin secretion in response to glucose by modulating the activity of Akt, whereas only raptor is able to control insulin biosynthesis.
Primary Intravascular Synovial Sarcoma: Case Report
Authors: Tuncer Osman Nuri , Erbasan Ozan , Golbasi İlhan
Published: October 2012

Synovial sarcoma (SS), a mesenchymal spindle cell tumor, displays variable epithelial differentiation, including glandular formation, and features a specific chromosomal translocation, t(X;18)(p11;q11). SS accounts for 5% to 10% of soft-tissue sarcomas. These tumors occur mostly in the joints, especially near the knee, but they also occur in other locations. Primary intravascular SS (IVSS) are extremely rare; only 6 well-documented cases have been reported in the English literature. We describe a new case of primary IVSS of the superior vena cava (SVC) in a 16-year-old boy. A transthoracic echocardiogram confirmed a large (4.8 ◊ 4.6 cm) circumscribed mass filling the right atrium, as well as a moderate pericardial effusion. The mass extended from the SVC to the tricuspid valve but did not prevent valve coaptation. Surgery via a transatrial approach revealed a huge mass (8 to 12 cm) attached to the SVC via a 5-mm pedicle. The tumor was excised, and the patient experienced an uneventful postoperative course. Fluorescence in situ hybridization analysis revealed the presence of the SS-specific translocation.
Is Prophylactic Intravenous Administration of a Proton Pump Inhibitor Necessary for Perioperative Management of Cardiac Surgery?
Authors: Fujita Kishu , Hata Mitsumasa , Sezai Akira , Sekino Hisakuni , Minami Kazutomo
Published: October 2012

Background: Mortality from gastrointestinal (GI) hemorrhage caused by antiplatelet or anticoagulant therapy (or both) is quite high after cardiac surgery. We previously reported that proton pump inhibitor (PPI) therapy is indispensable in preventing postoperative GI complications. PPIs are usually administered intravenously immediately after surgery and subsequently by oral formulations. We conducted a prospective study to evaluate whether intravenous PPI followed by oral administration is more efficient as prophylaxis than oral-only administration.

Methods and Results: We enrolled 40 patients scheduled to undergo coronary artery bypass grafting with cardiopulmonary bypass and randomly assigned them to receive oral PPIs alone (group 1) or intravenous PPI followed by oral administration (group 2). Postoperative upper GI endoscopy evaluations showed no evidence of GI bleeding. Only gastritis, esophagitis, and hiatal hernia were observed at similar incidences in the groups. Mean hospital stays were also similar, but the cost of PPI treatment was significantly lower in group 1.

Conclusion: No additional benefits of intravenous PPIs over oral formulations were demonstrated. Oral PPIs alone were effective and economical as prophylaxis against GI complications. Intravenous PPIs might be unnecessary in selected patients after cardiac surgery.
Does Payer Status Impact Clinical Outcomes after Cardiac Surgery? A Propensity Analysis
Authors: Polanco Antonio , Breglio Andrew M. , Itagaki Shinobu , Goldstone Andrew B. , Chikwe Joanna
Published: October 2012

Background: Medicaid patients bear proportionately greater financial responsibility for the cost of outpatient care and medication than non-Medicaid patients. We hypothesized that this difference in provision of continuing care would be associated with adverse clinical outcomes after cardiac surgery.

Materials and Methods: In a retrospective cohort analysis, 5056 consecutive adult patients undergoing cardiac surgery at a single institution between 2005 and 2010 were divided according to payer status. Propensity scores were calculated using 16 preoperative and demographic variables for each patient, and 461 1:1 propensity score-matched pairs were analyzed. Patient socioeconomic position was determined using aggregate data derived from zip codes. The main outcome measures were early mortality, postoperative complications, and patient survival.

Results: In multivariate analysis, Medicaid was found to be an independent predictor of worse survival after cardiac surgery (hazard ratio [HR], 2.1; 95% confidence interval [CI], 1.2-3.7; P = .01). No significant difference was observed in operative mortality in the 2 groups. After propensity score matching and controlling for socioeconomic position, the only independent predictors of worse midterm survival were an ejection fraction = 30% (HR, 1.7; 95% CI, 1.1-2.7; P = .02) and a higher logistic EuroSCORE (HR, 1.03; 95% CI, 1.0-1.1; P = .02).

Conclusions: Comorbidity and lower socioeconomic status appear to be more important predictors of late mortality after cardiac surgery than payer status, which does not have a significant impact on survival.
A Surgical Strategy for Cor Triatriatum Atrial Septal Defect�A1 Lam Subclass
Authors: Khoshbin Espeed , Tang Augustine , Brodison Adrian , Sogliani Franco
Published: October 2012

Atrial fibrillation and a heart murmur were diagnosed in a 68-year-old woman during a routine medical examination. She presented 2 years later with pulmonary edema. A transthoracic echocardiography examination revealed a tunneled atrial septal defect (ASD) and severe tricuspid regurgitation. Transesophageal echocardiography and 3-dimensional computed tomography evaluations revealed multiple intracardiac defects, including abnormal atrial septation suggestive of a typical cor triatriatum sinistrum (A1 Lam subclass), a rare congenital defect in adults. The patient underwent tricuspid valve repair with concomitant closure of the ASD by using the cor triatriatum curtain to form an autologous transposition flap. The intraoperative transesophageal and predischarge imaging evaluations confirmed an excellent repair. The patient made a swift recovery and demonstrated improvement in her symptoms at follow-up. This previously undescribed technique eliminates the need for a prosthetic implant and is applicable in >80% of cor triatriatum cases in which an ASD exists.
Anomalous Left Coronary Artery from the Pulmonary Arteryin an Adult
Authors: Vossler John D. , Entrikin Daniel W. , Quartermain Michael D. , Kon Neal D. , Ungerleider Ross M. , Ootaki Yoshio
Published: October 2012

Anomalous left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital heart defect that usually presents before the age of 1 year. Several surgical options exist for the correction of ALCAPA; however, debate continues regarding the optimal repair technique in adult populations. We report the case of successful surgical repair of ALCAPA with a direct aortic implantation technique in a 44-year-old mother of 4 children.
Fonte proteica na criação de Diatraea saccharalis e seu reflexo na produção e no controle de qualidade de Cotesia flavipes
Authors: Vacari Alessandra Marieli , Genovez Giovani de Souza , Laurentis Valéria Lucas de , Bortoli Sergio Antonio De
Published: October 2012

O objetivo do trabalho foi avaliar diferentes dietas para lagartas de Diatraea saccharalis, com o intuito de obter informações sobre as características biológicas da praga e consequentemente avaliar a qualidade do parasitoide Cotesia flavipes, visando melhorar tecnicamente sua produção massal. Lagartas de 24 horas de idade foram transferidas para tubos (25 lagartas/tubo) contendo dieta artificial com levedura de cerveja e germe de trigo e outra somente com germe de trigo como fonte de proteína. Depois de aproximadamente 15 dias, as lagartas foram retiradas dos tubos e acondicionadas em placas com dieta, sendo observadas lagartas de D. saccharalis não parasitadas e parasitadas para avaliação das características biológicas de D. saccharalis e C. flavipes.nas diferentes dietas. Além da observação das características biológicas de D. saccharalis, foram realizadas medições nas lagartas de 15 dias de idade. Também, massas de pupas de C. flavipes.produzidas em biofábrica foram classificadas em três diferentes tamanhos, sendo pequenas (1,3 a 2,5 cm de comprimento), médias (2,5 a 3,5 cm de comprimento) e grandes (3,5 a 4,0 cm de comprimento). Após a emergência dos adultos foi realizado o parasitismo em lagartas de D. saccharalis, sendo observados o número de machos e fêmeas, tamanho da massa, razão sexual e número de pupas inviáveis. A dieta artificial que contém somente germe de trigo é a mais indicada para criação massal do hospedeiro D. saccharalis para produção em larga escala de C. flavipes. Massas de pupas classificadas como grandes possuem melhor qualidade em criações massais de C. flavipes.
Análise da aplicabilidade do modelo gerencial na administração municipal
Authors: Araújo Priscila Gomes de , Pereira José Roberto
Published: October 2012

Esse artigo tem como objetivo identificar e analisar as razões pelas quais a administração de um município do estado de Minas Gerais não adotou, integralmente, o modelo gerencial, tendo percorrido mais de 15 anos desde a última reforma do estado e mais de oito anos do Choque de Gestão de Minas Gerais. Para tanto, utilizou-se como parâmetro de análise e investigação o Índice de Administração Pública Gerencial (IAPG), desenvolvido por Freitas Jr. (2009), com base nos pressupostos teóricos do modelo de administração pública gerencial. Nesse sentido, foi realizada uma análise das características e objetivos do modelo gerencial, bem como a demonstração dos esforços para utilização desse modelo na administração pública brasileira nos três níveis de governo. A abordagem metodológica utilizada é qualitativa e de natureza teórico-empírica, adotando-se como instrumento de coleta de informações um roteiro de entrevistas abertas com prefeitos, chefes de gabinete, vereadores e secretários das duas últimas gestões municipais, que correspondem aos mandatos de 2001 a 2004 e de 2005 a 2008. Os resultados alcançados mostram que o maior entrave para a adoção efetiva do modelo de administração pública gerencial no município é a falta de capacidade de gerenciamento e conhecimento dos próprios prefeitos em relação ao modelo. Nesse sentido, verificou-se a necessidade de formar e qualificar os gestores públicos municipais em administração pública para atuarem, profissionalmente, na realidade local, bem como fortalecer os canais de participação da população, como forma de controle social da gestão pública.
O colegiado de desenvolvimento territorial e a gestão social de políticas públicas: o caso do Território Serra do Brigadeiro, Minas Gerais
Authors: Freitas Alan Ferreira de , Freitas Alair Ferreira de , Dias Marcelo Miná
Published: October 2012

Este trabalho analisa a dinâmica de participação dos atores sociais na gestão social da política de desenvolvimento territorial e como ela influencia o processo de alocação dos recursos públicos por meio da elaboração e monitoramento dos projetos no Território Serra do Brigadeiro (TSB), Minas Gerais. Constata-se que a experiência da política permitiu construir e legitimar uma nova institucionalidade (Colegiado Territorial), que viabilizou a discussão e seleção de projetos coletivos. O colegiado, por meio de sua ação deliberativa, conseguiu estabelecer uma agenda relativamente autônoma, o que possibilitou discussões mais amplas sobre o desenvolvimento rural, apesar das limitações da operacionalização do programa de política pública e da qualidade da participação.
Cooperação intermunicipal na bacia do rio Paraopeba
Authors: Matos Fernanda , Dias Reinaldo
Published: October 2012

Neste artigo aborda-se o processo da descentralização do poder da esfera federal para o nível local, a responsabilidade dos consórcios e os fatores que dificultam e facilitam a cooperação intermunicipal. Os consórcios têm se mostrado uma alternativa para o gerenciamento das atribuições municipais. Este modelo gerencial propõe a participação de todos os atores sociais no gerenciamento das questões de interesse comum. O trabalho fornece uma visão geral sobre a cooperação intermunicipal, em especial na bacia do rio Paraopeba - Minas Gerais, Brasil -, a partir da análise de questionários direcionados aos gestores dos municípios. Evidencia-se uma abertura por parte dos municípios à participação em consórcios, considerando que 83% dos municípios da bacia fazem parte de um ou mais tipos de arranjos intermunicipais e, também, a necessidade de desenvolvimento de ações para melhorar e/ou apoiar a cooperação entre os municípios.
Empreendedores de políticas públicas na implementação de programas governamentais
Authors: Lima Maria Lúcia de Oliveira Feliciano de , Medeiros Janann Joslin
Published: October 2012

Este artigo traz novo olhar para a implementação de programas governamentais, aproximando as literaturas de políticas públicas, implementação e inovação. Procurou-se investigar a forma de atuação de diretoras de escolas do Distrito Federal na implementação de dois programas distritais. Foi evidenciado que há, entre as entrevistadas, pessoas que se aproximam de champions e de empreendedores de políticas públicas e que há características que diferenciam implementadores empreendedores de não empreendedores. Foram encontradas semelhanças entre os conceitos de champions, empreendedores de políticas públicas e implementadores de programas, assim como há pontos em comum entre as fases de inovação e as etapas do ciclo de políticas públicas. Essas semelhanças abrem a possibilidade de diálogo frutífero entre esses dois campos de estudo e possibilita a ampliação dos estudos sobre implementação.
Gestão Social: notícias sobre o campo de estudos e práticas a partir das interações e debates do VI Enapegs
Authors: Mendonça Patrícia Maria E. , Gonçalves-Dias Sylmara Lopes Francelino , Junqueira Luciano A. Prates
Published: October 2012

Este texto busca relatar a realização do evento Encontro Nacional da Rede de Pesquisadores em Gestão Social (Enapegs), que teve sua última edição em maio de 2012, em São Paulo. Para tanto, busca delimitar o que vem a ser o campo de estudos sobre Gestão Social, a constituição da Rede de Pesquisadores em Gestão Social (RGS), bem como a dinâmica de construção e realização do Enapegs e suas principais discussões e resultados, que no último encontro teve como temática: Gestão Social: mobilizações e conexões.
Mineralogia e gênese de argissolos das Serras do Tabuleiro/Itajaí, Estado de Santa Catarina
Authors: Brighenti Italomir , Almeida Jaime Antonio de , Hofer Andrey
Published: October 2012

As rochas do escudo cristalino, que afloram na porção centro-leste e nordeste do Estado de Santa Catarina, estão dispostas em relevo forte ondulado e montanhoso da unidade geomorfológica Serras do Tabuleiro/Itajaí. A movimentada superfície é resultante dos ciclos tecto magmático metamórficos sofridos pela crosta, responsáveis pelo retrabalhamento de rochas muito antigas formadas do Arqueano ao Proterozoico. Esse compartimento é constituído por rochas metamórficas, e informações sobre pedogênese e composição mineralógica dos solos delas derivados são escassas, fator que motivou a condução deste trabalho. Cinco perfis resultantes da pedogênese desses materiais foram estudados. O primeiro, desenvolvido de hornblendito do Complexo Granulítico de Santa Catarina (P1), foi descrito no topo de elevação em Pomerode, em condições de relevo forte ondulado. O segundo e o quinto perfis (P2 e P5), ambos desenvolvidos de granulitos máficos do mesmo complexo, respectivamente em Massaranduba e Blumenau, foram descritos na base da encosta, em relevo local ondulado. O terceiro perfil (P3), resultante da alteração de xistos do Complexo Metamórfico Brusque, foi descrito em encosta de relevo forte ondulado, em Botuverá. O quarto perfil (P4) foi fruto da pedogênese de granitoides foliados da faixa Granito-Gnáissica Faxinal, sendo descrito no terço inferior da encosta, num relevo ondulado. Foram feitas descrições gerais e morfológicas dos solos e da litologia subjacente, análises físicas e químicas de caracterização e análises mineralógicas da fração argila por difratometria de raios X (DRX), procurando avaliar as transformações sofridas pelos minerais presentes nas rochas durante a evolução dos solos. Todos os solos apresentaram alta relação textural e, ou, grau de desenvolvimento de estrutura em blocos, associada à presença de cerosidade, caracterizando a presença de horizonte diagnóstico B textural, com argila de atividade baixa ou alta e caráter distrófico, alumínico ou alítico, o que permitiu classificá-los como Argissolo Amarelo distrófico típico (P1), Argissolo Amarelo alítico típico (P2, P3 e P5) e Argissolo Vermelho-Amarelo alumínico típico (P4) no Sistema Brasileiro de Classificação de Solos, versão de 2006. Em todos os Argissolos predominou caulinita, secundada por argilominerais do grupo da ilita, interestratificados ilita-vermiculita e, ou, vermiculita com polímeros de hidroxi-Al entrecamadas. Gibbsita, em baixas quantidades, também foi constatada nos perfis P2, P3 e P5. A formação de caulinita é resultante da dissolução de minerais primários, favorecida pelas condições climáticas subtropicais úmidas. Os argilominerais com estrutura 2:1 são provavelmente resultantes da transformação de filossilicatos presentes no material originário. O aumento da atividade da fração argila dos solos relacionou-se com o aumento na quantidade de argilominerais 2:1, cuja proporção foi mais alta no Argissolo desenvolvido de Muscovita-Xisto.
Isolamento e prospecção de bactérias endofíticas e epifíticas na cana-de-açúcar em áreas com e sem cupinicida
Authors: Silva Michelangelo de Oliveira , Freire Fernando José , Lira Junior Mario Andrade , Kuklinsky-Sobral Júlia , Costa Diogo Paes da , Lira-Cadete Luana
Published: October 2012

A exploração e o conhecimento dos mecanismos de interação bactéria-planta podem ser utilizados para a produção sustentável de diversas culturas, como a cana-de-açúcar. O objetivo deste trabalho foi isolar e prospectar bactérias associadas à cultura da cana-de-açúcar com capacidade de fixar nitrogênio e solubilizar fosfato inorgânico em áreas com e sem aplicação de cupinicida. Bactérias endofíticas, de folha e raiz, e do rizoplano foram isoladas de três variedades comerciais (RB 92579, RB 867515 e RB 863129) de cana-de-açúcar, cultivadas no Nordeste brasileiro, em áreas com e sem aplicação de cupinicida, aos quatro meses após o plantio. Foram obtidos 272 isolados, selecionados quanto à sua capacidade de solubilizar fosfato inorgânico e fixar nitrogênio. O uso do cupinicida não provocou alterações nas comunidades microbianas endofíticas de folha e raiz e epifíticas do rizoplano. As variedades estudadas apresentam uma comunidade bacteriana associada com potencial aplicação para a promoção de crescimento vegetal, pois possuem a capacidade de fixar N2 e solubilizar fosfato inorgânico.
Performance of a reciprocal shaker in mechanical dispersion of soil samples for particle-size analysis
Authors: Dourado Thayse Aparecida , Silva Laura Fernanda Simões da , Marinho Mara de Andrade
Published: October 2012

The dispersion of the samples in soil particle-size analysis is a fundamental step, which is commonly achieved with a combination of chemical agents and mechanical agitation. The purpose of this study was to evaluate the efficiency of a low-speed reciprocal shaker for the mechanical dispersion of soil samples of different textural classes. The particle size of 61 soil samples was analyzed in four replications, using the pipette method to determine the clay fraction and sieving to determine coarse, fine and total sand fractions. The silt content was obtained by difference. To evaluate the performance, the results of the reciprocal shaker (RSh) were compared with data of the same soil samples available in reports of the Proficiency testing for Soil Analysis Laboratories of the Agronomic Institute of Campinas (Prolab/IAC). The accuracy was analyzed based on the maximum and minimum values defining the confidence intervals for the particle-size fractions of each soil sample. Graphical indicators were also used for data comparison, based on dispersion and linear adjustment. The descriptive statistics indicated predominantly low variability in more than 90 % of the results for sand, medium-textured and clay samples, and for 68 % of the results for heavy clay samples, indicating satisfactory repeatability of measurements with the RSh. Medium variability was frequently associated with silt, followed by the fine sand fraction. The sensitivity analyses indicated an accuracy of 100 % for the three main separates (total sand, silt and clay), in all 52 samples of the textural classes heavy clay, clay and medium. For the nine sand soil samples, the average accuracy was 85.2 %; highest deviations were observed for the silt fraction. In relation to the linear adjustments, the correlation coefficients of 0.93 (silt) or > 0.93 (total sand and clay), as well as the differences between the angular coefficients and the unit < 0.16, indicated a high correlation between the reference data (Prolab/IAC) and results obtained with the RSh. In conclusion, the mechanical dispersion by the reciprocal shaker of soil samples of different textural classes was satisfactory. The results allowed recommending the use of the equipment at low agitation for particle size- analysis. The advantages of this Brazilian apparatus are its low cost, the possibility to simultaneously analyze a great number of samples using ordinary, easily replaceable glass or plastic bottles.
Contribution of macroporosity to water flux of a soil under different tillage systems
Authors: Soracco Carlos Germán , Lozano Luis Alberto , Balbuena Roberto , Ressia Juan Manuel , Filgueira Roberto Raúl
Published: October 2012

In view of the importance of the macroporosity for the water transport properties of soils, its quantitative assessment is a challenging task. Measurements of hydraulic conductivity (K) at different soil water tensions and the quantification of water-conducting macropores (θM) of a soil under different tillage systems could help understand the effects on the soil porous system and related hydraulic properties. The purpose of this study was to assess the effects of Conventional Tillage (CT), Chisel Plow (CP) and No Tillage (NT) on θM and on K; and to quantify the contribution of macroporosity to total water flux in a loam soil. A tension disc infiltrometer was used at two soil water pressure heads (-5 cm, and 0) to infer θM and K, during fallow. Macroporosity was determined based on the flow contribution between 0 and -5 cm water potentials (K0, K5, respectively), according to the Hagen-Poiseuille equation. The K0 values were statistically higher for CT than for NT and CP. The K5 values did not differ statistically among treatments. The mean K values varied between 0.20 and 3.70 cm/h. For CT, θM was significantly greater than for CP and NT, following the same trend as K0. No differences in θM were detected between CP and NT. With CT, the formation of water-conducting macropores with persistence until post-harvest was possible, while under CP preparation, the water-conducting macropores were not persistent. These results support the idea that tillage affects the soil water movement mainly by the resulting water-conducting macropores. Future studies on tillage effects on water movement should focus on macroporosity.
Frações de carbono em topossequências de solos sob eucalipto com diferentes históricos de uso
Authors: Silva Elen Alvarenga , Silva Carlos Alberto , Silva Ivo Ribeiro , Marques João José G. S. M. , Araujo Elias Frank de , Carvalho Samara Andrade de , Silva Sérgio Henrique Godinho , Curi Nilton
Published: October 2012

No Brasil, boa parte dos plantios florestais tem sido realizada em solos que apresentam algum grau de degradação física, química ou biológica. A proteção ao solo fornecida pelas árvores, em função da deposição de serapilheira, constitui um dos processos de recuperação de áreas degradadas, e, como a matéria orgânica está relacionada com muitos dos atributos físicos, químicos e biológicos do solo, ela se caracteriza como um fator-chave na manutenção da qualidade ambiental de sistemas florestais. Assim, objetivou-se neste trabalho caracterizar frações da matéria orgânica em solos sob cultivo mínimo de eucalipto com diferentes históricos de uso e posições na paisagem. O estudo foi realizado em três hortos florestais (HFs): Terra Dura, Canafístula e Sanga das Pedras, cultivados com eucalipto no Estado do Rio Grande do Sul. Os solos foram amostrados nas profundidades de 0-5, 5-20 e 20-40 cm. Na profundidade de 0-5 cm, a maioria dos Argissolos dos HFs estudados apresentou teores de carbono orgânico (CO) superiores aos de matas nativas adjacentes. Nas áreas cultivadas, há maior armazenamento de CO no HF Canafístula, sendo notados, em geral, menores teores de CO no terço inferior da encosta em relação às outras posições das topossequências avaliadas. O índice de humificação, em geral, é maior nas áreas de mata em comparação às áreas cultivadas; contudo, ele varia em função da profundidade do solo, da posição amostrada na topossequência e do HF avaliado. Nas profundidades de 0-5 e 5-20 cm, a abundância natural de 13C dos HFs é similar à das áreas de mata nativa, porém há maior teor de 13C na camada mais profunda dos solos cultivados, o que sinaliza para a contribuição à matéria orgânica do solo (MOS) de C oriundo das pastagens que antecederam o eucalipto.
Organic matter quality and dynamics in tropical soils amended with sugar industry residue
Authors: Busato Jader Galba , Leão Tairone Paiva , Baldotto Marihus Altoé , Canellas Luciano Pasqualoto
Published: October 2012

Soil organic matter depletion caused by agricultural management systems have been identified as a critical problem in most tropical soils. The application of organic residues from agro-industrial activities can ameliorate this problem by increasing soil organic matter quality and quantity. Humic substances play an important role in soil conservation but the dynamics of their transformations is still poorly understood. This study evaluated the effect of compost application to two contrasting tropical soils (Inceptisol and Oxisol) for two years. Soil samples were incubated with compost consisting of sugarcane filter cake, a residue from the sugar industry, at 0, 40, 80, and 120 Mg ha-1. Filter cake compost changed the humic matter dynamics in both content and quality, affecting the soil mineralogical composition. It was observed that carbon mineralization was faster in the illite-containing Inceptisol, whereas humic acids were preserved for a longer period in the Oxisol. In both soils, compost application increased fulvic acid contents, favoring the formation of small hydrophilic molecules. A decrease in fluorescence intensity according to the incubation time was observed in the humic acids extracted from amended soils, revealing important chemical changes in this otherwise stable C pool.
Nitrogen balance in soil under eucalyptus plantations
Authors: Barreto Patrícia Anjos Bittencourt , Gama-Rodrigues Antonio Carlos da , Gama-Rodrigues Emanuela Forestieri da , Barros Nairam Félix de
Published: October 2012

An understanding of the role of organic nitrogen (N) pools in the N supply of eucalyptus plantations is essential for the development of strategies that maximize the efficient use of N for this crop. This study aimed to evaluate the distribution of organic N pools in different compartments of the soil-plant system and their contributions to the N supply in eucalyptus plantations at different ages (1, 3, 5, and 13 years). Three models were used to estimate the contributions of organic pools: Model I considered N pools contained in the litterfall, N pools in the soil microbial biomass and available soil N (mineral N); Model II considered the N pools in the soil, potentially mineralizable N and the export of N through wood harvesting; and Model III (N balance) was defined as the difference between the initial soil N pool (0-10 cm) and the export of N, taking the application of N fertilizer into account. Model I showed that N pools could supply 27 - 70 % of the N demands of eucalyptus trees at different ages. Model II suggested that the soil N pool may be sufficient for 4 - 5 rotations of 5 years. According to the N balance, these N pools would be sufficient to meet the N demands of eucalyptus for more than 15 rotations of 5 years. The organic pools contribute with different levels of N and together are sufficient to meet the N demands of eucalyptus for several rotations.
Disponibilidade de zinco para mudas de eucalipto em solos de Cerrado
Authors: Rodrigues Fernando Antonio Vieira , Barros Nairam Félix de , Neves Júlio César Lima , Alvarez V Víctor Hugo , Novais Roberto Ferreira
Published: October 2012

No Brasil, com a expansão da silvicultura clonal, o plantio de materiais genéticos mais produtivos e exigentes nutricionalmente tem aumentado o aparecimento de sintomas de deficiência de micronutrientes, principalmente de B, e, mais recentemente, de Cu e de Zn, sobretudo em áreas de Cerrado. Este trabalho teve por objetivo avaliar três métodos de determinação da disponibilidade de Zn (Mehlich-1, Mehlich-3 e DTPA pH 7,3) para mudas de eucalipto cultivadas em casa de vegetação, em amostras de seis solos de Cerrado, bem como a influência de propriedades do solo na eficiência desses extratores. Os tratamentos foram arranjados no esquema fatorial 6 x 5, correspondendo a seis solos e cinco doses de Zn (0, 2,5, 5, 10 e 20 mg dm-3), com quatro repetições, em blocos ao acaso. Os níveis críticos de Zn em solos de Cerrado, para o crescimento de mudas de eucalipto, são iguais ou inferiores a 0,23 e 0,05 mg dm-3, pelos extratores Mehlich-1 e DTPA, respectivamente. Os teores de Zn no solo pelos três extratores, assim como os teores e conteúdo na planta, aumentam com a elevação das doses adicionadas de Zn e são altamente correlacionados entre si. A avaliação da disponibilidade de Zn para mudas de eucalipto pode ser feita com qualquer um dos três extratores; entretanto, o Mehlich-1 é o mais recomendado, pela facilidade operacional deste método em relação aos outros e por ele já ser usado na grande maioria dos laboratórios do país.
Consistência hidrológica de modelos digitais de elevação (MDE) para definição da rede de drenagem na sub-bacia do horto florestal Terra Dura, Eldorado do Sul, RS
Authors: Oliveira Anna Hoffmann , Silva Marx Leandro Naves , Curi Nilton , Klinke Neto Gustavo , Silva Mayesse Aparecida da , Araújo Elias Frank de
Published: October 2012

O desenvolvimento da erosão hídrica ocorre em resposta ao modo como a água se move através e sobre uma determinada paisagem. O modelo digital de elevação (MDE) deve, portanto, ser o mais preciso possível, uma vez que constitui a base para a análise do relevo. Este trabalho teve como objetivo definir um modelo digital de elevação hidrologicamente consistente (MDEHC) e o método de direção de fluxo mais adequado para a definição da rede de drenagem na sub-bacia do horto florestal Terra Dura, município de Eldorado do Sul, RS. Foram testados os modelos gerados com os interpoladores Topogrid e redes triangulares irregulares (Triangulated Irregular Network -TIN) linear (TIN L) e TIN natural neighbor (TIN NN). A qualidade em relação às análises hidrológicas foi avaliada por meio da comparação das curvas de nível geradas pelos modelos testados com as curvas originais da sub-bacia (escala 1:10.000); da avaliação da quantidade de áreas planas; e da comparação da drenagem gerada pelos modelos a partir dos métodos de direção de fluxo Deterministic (D8) e Deterministic infinity (D∞ ou D infinito) com a drenagem original. Entre os modelos avaliados, o Topogrid apresentou maior consistência hidrológica, verificada na melhor continuidade das curvas de nível (menos arestas) e maior detalhamento da área de drenagem e divisores, acarretando menor quantidade de áreas planas e caminhos de fluxo mais detalhados, independentemente do método de direção de fluxo utilizado. Em relação à rede de drenagem, o método distribuído D∞ obteve melhor desempenho na descrição dos caminhos de fluxo, comparado ao método de direção única D8. O MDEHC Topogrid associado ao método D∞ proporcionou a identificação mais precisa dos caminhos preferenciais do fluxo que formam a rede de drenagem.
Physical properties and particle-size fractions of soil organic matter in crop-livestock integration
Authors: Tirloni Carolina , Vitorino Antonio Carlos Tadeu , Bergamin Anderson Cristian , Souza Luiz Carlos Ferreira de
Published: October 2012

Crop-livestock integration represents an interesting alternative of soil management, especially in regions where the maintenance of cover crops in no-tillage systems is difficult. The objective of this study was to evaluate soil physical and chemical properties, based on the hypothesis that a well-managed crop-livestock integration system improves the soil quality and stabilizes the system. The experiment was set up in a completely randomized design, with five replications. The treatments were arranged in a 6 x 4 factorial design, to assess five crop rotation systems in crop-livestock integration, and native forest as reference of soil undisturbed by agriculture, in four layers (0.0-0.05; 0.05-0.10; 0.10-0.15 and 0.15-0.20 m). The crop rotation systems in crop-livestock integration promoted changes in soil physical and chemical properties and the effects of the different systems were mainly detected in the surface layer. The crops in integrated crop-livestock systems allowed the maintenance of soil carbon at levels equal to those of the native forest, proving the efficiency of these systems in terms of soil conservation. The systems influenced the environmental stability positively; the soil quality indicator mineral-associated organic matter was best related to aggregate stability.