bluuebunny/crossref_metadata_2025 huggingface dataset:
A Computational Model for Epidural Electrical Stimulation of Spinal Sensorimotor Circuits
Authors: Capogrosso Marco , Wenger Nikolaus , Raspopovic Stanisa , Musienko Pavel , Beauparlant Janine , Bassi Luciani Lorenzo , Courtine Grégoire , Micera Silvestro
Published: December 2013

Epidural electrical stimulation (EES) of lumbosacral segments can restore a range of movements after spinal cord injury. However, the mechanisms and neural structures through which EES facilitates movement execution remain unclear. Here, we designed a computational model and performedin vivoexperiments to investigate the type of fibers, neurons, and circuits recruited in response to EES. We first developed a realistic finite element computer model of rat lumbosacral segments to identify the currents generated by EES. To evaluate the impact of these currents on sensorimotor circuits, we coupled this model with an anatomically realistic axon-cable model of motoneurons, interneurons, and myelinated afferent fibers for antagonistic ankle muscles. Comparisons between computer simulations and experiments revealed the ability of the model to predict EES-evoked motor responses over multiple intensities and locations. Analysis of the recruited neural structures revealed the lack of direct influence of EES on motoneurons and interneurons. Simulations and pharmacological experiments demonstrated that EES engages spinal circuits trans-synaptically through the recruitment of myelinated afferent fibers. The model also predicted the capacity of spatially distinct EES to modulate side-specific limb movements and, to a lesser extent, extension versus flexion. These predictions were confirmed during standing and walking enabled by EES in spinal rats. These combined results provide a mechanistic framework for the design of spinal neuroprosthetic systems to improve standing and walking after neurological disorders.
Sodium Channels Contribute to Degeneration of Dorsal Root Ganglion Neurites Induced by Mitochondrial Dysfunction in anIn VitroModel of Axonal Injury
Authors: Persson Anna-Karin , Kim Insil , Zhao Peng , Estacion Mark , Black Joel A. , Waxman Stephen G.
Published: December 2013

Axonal degeneration occurs in multiple neurodegenerative disorders of the central and peripheral nervous system. Although the underlying molecular pathways leading to axonal degeneration are incompletely understood, accumulating evidence suggests contributions of impaired mitochondrial function, disrupted axonal transport, and/or dysfunctional intracellular Ca2+-homeostasis in the injurious cascade associated with axonal degeneration. Utilizing anin vitromodel of axonal degeneration, we studied a subset of mouse peripheral sensory neurons in which neurites were exposed selectively to conditions associated with the pathogenesis of axonal neuropathiesin vivo. Rotenone-induced mitochondrial dysfunction resulted in neurite degeneration accompanied by reduced ATP levels and increased ROS levels in neurites. Blockade of voltage-gated sodium channels with TTX and reverse (Ca2+-importing) mode of the sodium-calcium exchanger (NCX) with KB-R7943 partially protected rotenone-treated neurites from degeneration, suggesting a contribution of sodium channels and reverse NCX activity to the degeneration of neurites resulting from impaired mitochondrial function. Pharmacological inhibition of the Na+/K+-ATPase with ouabain induced neurite degeneration, which was attenuated by TTX and KB-R7943, supporting a contribution of sodium channels in axonal degenerative pathways accompanying impaired Na+/K+-ATPase activity. Conversely, oxidant stress (H2O2)-induced neurite degeneration was not attenuated by TTX. Our results demonstrate that both energetic and oxidative stress targeted selectively to neurites induces neurite degeneration and that blockade of sodium channels and of reverse NCX activity blockade partially protects neurites from injury due to energetic stress, but not from oxidative stress induced by H2O2.
Pharmacologic Inhibition of ROCK2 Suppresses Amyloid-β Production in an Alzheimer's Disease Mouse Model
Authors: Herskowitz Jeremy H. , Feng Yangbo , Mattheyses Alexa L. , Hales Chadwick M. , Higginbotham Lenora A. , Duong Duc M. , Montine Thomas J. , Troncoso Juan C. , Thambisetty Madhav , Seyfried Nicholas T. , Levey Allan I. , Lah James J.
Published: December 2013

Alzheimer's disease (AD) is the leading cause of dementia and has no cure. Genetic, cell biological, and biochemical studies suggest that reducing amyloid-β (Aβ) production may serve as a rational therapeutic avenue to delay or prevent AD progression. Inhibition of RhoA, a Rho GTPase family member, is proposed to curb Aβ production. However, a barrier to this hypothesis has been the limited understanding of how the principal downstream effectors of RhoA, Rho-associated, coiled-coil containing protein kinase (ROCK) 1 and ROCK2, modulate Aβ generation. Here, we report that ROCK1 knockdown increased endogenous human Aβ production, whereas ROCK2 knockdown decreased Aβ levels. Inhibition of ROCK2 kinase activity, using an isoform-selective small molecule (SR3677), suppressed β-site APP cleaving enzyme 1 (BACE1) enzymatic action and diminished production of Aβ in AD mouse brain. Immunofluorescence and confocal microscopy analyses revealed that SR3677 alters BACE1 endocytic distribution and promotes amyloid precursor protein (APP) traffic to lysosomes. Moreover, SR3677 blocked ROCK2 phosphorylation of APP at threonine 654 (T654); in neurons, T654 was critical for APP processing to Aβ. These observations suggest that ROCK2 inhibition reduces Aβ levels through independent mechanisms. Finally, ROCK2 protein levels were increased in asymptomatic AD, mild cognitive impairment, and AD brains, demonstrating that ROCK2 levels change in the earliest stages of AD and remain elevated throughout disease progression. Collectively, these findings highlight ROCK2 as a mechanism-based therapeutic target to combat Aβ production in AD.
Synaptic Plasticity and PDGF Signaling Defects Underlie Clinical Progression in Multiple Sclerosis
Authors: Mori Francesco , Rossi Silvia , Piccinin Sonia , Motta Caterina , Mango Dalila , Kusayanagi Hajime , Bergami Alessandra , Studer Valeria , Nicoletti Carolina G. , Buttari Fabio , Barbieri Francesca , Mercuri Nicola B. , Martino Gianvito , Furlan Roberto , Nisticò Robert , Centonze Diego
Published: December 2013

Neuroplasticity is essential to prevent clinical worsening despite continuing neuronal loss in several brain diseases, including multiple sclerosis (MS). The precise nature of the adaptation mechanisms taking place in MS brains, ensuring protection from disability appearance and accumulation, is however unknown. Here, we explored the hypothesis that long-term synaptic potentiation (LTP), potentially able to minimize the effects of neuronal loss by providing extra excitation of denervated neurons, is the most relevant form of adaptive plasticity in stable MS patients, and it is disrupted in progressing MS patients. We found that LTP, explored by means of transcranial magnetic theta burst stimulation over the primary motor cortex, was still possible, and even favored, in stable relapsing-remitting (RR-MS) patients, whereas it was absent in individuals with primary progressive MS (PP-MS). We also provided evidence that platelet-derived growth factor (PDGF) plays a substantial role in favoring both LTP and brain reserve in MS patients, as this molecule: (1) was reduced in the CSF of PP-MS patients, (2) enhanced LTP emergence in hippocampal mouse brain slices, (3) was associated with more pronounced LTP in RR-MS patients, and (4) was associated with the clinical compensation of new brain lesion formation in RR-MS. Our results show that brain plasticity reserve, in the form of LTP, is crucial to contrast clinical deterioration in MS. Enhancing PDGF signaling might represent a valuable treatment option to maintain brain reserve and to attenuate the clinical consequences of neuronal damage in the progressive phases of MS and in other neurodegenerative disorders.
Effort-Related Motivational Effects of the VMAT-2 Inhibitor Tetrabenazine: Implications for Animal Models of the Motivational Symptoms of Depression
Authors: Nunes Eric J. , Randall Patrick A. , Hart Evan E. , Freeland Charlotte , Yohn Samantha E. , Baqi Younis , Müller Christa E. , López-Cruz Laura , Correa Mercè , Salamone John D.
Published: December 2013

Motivated behaviors are often characterized by a high degree of behavioral activation, and work output and organisms frequently make effort-related decisions based upon cost/benefit analyses. Moreover, people with major depression and other disorders often show effort-related motivational symptoms such as anergia, psychomotor retardation, and fatigue. It has been suggested that tasks measuring effort-related choice behavior could be used as animal models of the motivational symptoms of depression, and the present studies characterized the effort-related effects of the vesicular monoamine transport (VMAT) inhibitor tetrabenazine. Tetrabenazine produces depressive symptoms in humans and, because of its selective inhibition of VMAT-2, it preferentially depletes dopamine (DA). Rats were assessed using a concurrent fixed-ratio 5/chow feeding choice task that is known to be sensitive to dopaminergic manipulations. Tetrabenazine shifted response choice in rats, producing a dose-related decrease in lever pressing and a concomitant increase in chow intake. However, it did not alter food intake or preference in parallel free-feeding choice studies. The effects of tetrabenazine on effort-related choice were reversed by the adenosine A2Aantagonist MSX-3 and the antidepressant bupropion. A behaviorally active dose of tetrabenazine decreased extracellular DA in nucleus accumbens and increased expression of DARPP-32 in accumbens medium spiny neurons in a pattern indicative of reduced transmission at both D1and D2DA receptors. These experiments demonstrate that tetrabenazine, which is used in animal models to produce depression-like effects, can alter effort-related choice behavior. These studies have implications for the development of animal models of the motivational symptoms of depression and related disorders.
Diabetes AugmentsIn VivoMicrovascular Blood Flow Dynamics after Stroke
Authors: Tennant Kelly A. , Brown Craig E.
Published: December 2013

Stroke usually affects people with underlying medical conditions. In particular, diabetics are significantly more likely to have a stroke and the prognosis for recovery is poor. Because diabetes is associated with degenerative changes in the vasculature of many organs, we sought to determine how hyperglycemia affects blood flow dynamics after an ischemic stroke. Longitudinalin vivotwo-photon imaging was used to track microvessels before and after photothrombotic stroke in a diabetic mouse model. Chronic hyperglycemia exacerbated acute (3–7 d) ischemia-induced increases in blood flow velocity, vessel lumen diameter, and red blood cell flux in peri-infarct regions. These changes in blood flow dynamics were most evident in superficial blood vessels within 500 μm from the infarct, rather than deeper or more distant cortical regions. Long-term imaging of diabetic mice not subjected to stroke indicated that these acute stroke-related changes in vascular function could not be attributed to complications from hyperglycemia alone. Treating diabetic mice with insulin immediately after stroke resulted in less severe alterations in blood flow within the first 7 d of recovery, but had more variable results at later time points. Analysis of microvessel branching patterns revealed that stroke led to a pruning of microvessels in peri-infarct cortex, with very few instances of sprouting. These results indicate that chronic hyperglycemia significantly affects the vascular response to ischemic stroke and that insulin only partially mitigates these changes. The combination of these acute and chronic alterations in blood flow dynamics could underlie diabetes-related deficits in cortical plasticity and stroke recovery.
Transcranial Direct Current Stimulation (tDCS) of Left Parietal Cortex Facilitates Gesture Processing in Healthy Subjects
Authors: Weiss Peter H. , Achilles Elisabeth I. S. , Moos Katharina , Hesse Maike D. , Sparing Roland , Fink Gereon R.
Published: December 2013

Gesture processing deficits constitute a key symptom of apraxia, a disorder of motor cognition frequently observed after left-hemispheric stroke. The clinical relevance of apraxia stands in stark contrast to the paucity of therapeutic options available. Transcranial direct current stimulation (tDCS) is a promising tool for modulating disturbed network function after stroke. Here, we investigate the effect of parietal tDCS on gesture processing in healthy human subjects. Neuropsychological and imaging studies suggest that the imitation and matching of hand gestures involve the left inferior parietal lobe (IPL). Using neuronavigation based on cytoarchitectonically defined anatomical probability maps, tDCS was applied over left IPL-areas PF, PFm, or PG in healthy participants (n= 26). Before and after tDCS, subjects performed a gesture matching task and a person discrimination task for control. Changes in error rates and reaction times were analyzed for the effects of anodal and cathodal tDCS (compared with sham tDCS). Matching of hand gestures was specifically facilitated by anodal tDCS applied over the cytoarchitectonically defined IPL-area PFm, whereas tDCS over IPL-areas PF and PG did not elucidate significant effects. Taking into account tDCS electrode size and the central position of area PFm within IPL, it can be assumed that the observed effect is rather the result of a combined stimulation of the supramarginal and angular gyrus than an isolated PFm stimulation. Our data confirm the pivotal role of the left IPL in gesture processing. Furthermore, anatomically guided tDCS of the left IPL may constitute a promising approach to neurorehabilitation of apraxic patients with gesture processing deficits.
Regionalism in Southern Narratives of Vietnamese History
Authors: Ang Claudine
Published: December 2013

This essay explores the extent to which works published in the RVN between 1954 and 1975 constituted a coherent body of scholarship. Through a case study of the ways in which scholars represented the nam tiến in the journals of the DRV and the RVN, it makes an argument for using regionalism as an interpretive framework through which to examine the latent coherence in RVN scholarship. Particular attention is devoted to tracing the legacy of Nguyễn Dynasty historiography in important RVN publications, such as Tập San Sử Địa, Báo Bách Khoa, and Việt Nam Khảo Cổ Tập San.
From Liberally-Organized to Centralized Schools
Authors: Hoa Trần Thị Phương
Published: December 2013

This paper introduces a shift from freestyle Confucian learning to a centrally-controlled educational system in colonial Tonkin from 1885 to 1927. I examine the changes in education within this time frame, focusing on policy, legislation, finances, personnel resources, and schooling outcomes. I also discuss the drivers and impacts of this new, highly-centralized schooling system.
Sorafenib in the treatment of radioiodine-refractory differentiated thyroid cancer: a meta-analysis
Authors: Shen Chen-Tian , Qiu Zhong-Ling , Luo Quan-Yong
Published: December 2013

The advent of biologically targeted agents and increased understanding of thyroid carcinogenesis have generated much interest in the development of biologically targeted therapeutic agents for thyroid cancer. Among them, sorafenib is the most commonly studied drug. The current meta-analysis was carried out to estimate the efficacy and safety of sorafenib administered in radioiodine-refractory differentiated thyroid cancer patients. An electronic search was conducted using PubMed/MEDLINE and EMBASE. Statistical analyses were carried out using either random-effects or fixed-effects models according to heterogeneity. All the statistical analyses were carried out using the Stata version 12.0 software. Seven eligible studies were identified. The final results indicated that 22% of the patients (95% CI: 15–28) achieved a partial response. Hand–foot syndrome, diarrhea, fatigue, rash, weight loss, and hypertension were the most frequently observed adverse effects (AEs) associated with sorafenib use and the incidence of these AEs (all grades) was 80% (95% CI: 68–91), 68% (95% CI: 59–77), 67% (95% CI: 57–78), 66% (95% CI: 50–82), 52%(95% CI: 33–72), and 31% (95% CI: 21–42) respectively. Sixty-two percent (95% CI: 36-89) patients required dose reductions due to toxicity of sorafenib. As far as PR and AEs are concerned, the results of this meta-analysis indicate that sorafenib has a modest effect in patients with radioiodine-refractory differentiated thyroid cancer and the high incidence of AEs associated with this agent may affect the quality of patients' lives. Though the use of sorafenib in the treatment of radioiodine-refractory differentiated thyroid cancer is considered promising by most physicians working in this field, more effective agents with less toxicity and cost are still needed.
Differential regulation of endothelium behavior by progesterone and medroxyprogesterone acetate
Authors: Cutini Pablo H , Campelo Adrián E , Massheimer Virginia L
Published: December 2013

Medroxyprogesterone acetate (MPA) is a synthetic progestin commonly used in hormone replacement therapy (HRT). The aim of this research was to study and compare the effect of progesterone (Pg) and MPA on the regulation of cellular events associated with vascular homeostasis and disease. Platelet adhesion to endothelial cells (ECs), nitric oxide (NO) production, and cell migration were studied using murine ECsin vitroexposed to the progestins. After 7 min of treatment, MPA significantly inhibited NO synthesis with respect to control values; meanwhile, Pg markedly increased vasoactive production. In senile ECs, the stimulatory action of Pg decreases; meanwhile, MPA maintained its ability to inhibit NO synthesis. The presence of RU486 antagonized the action of each steroid. When ECs were preincubated with PD98059 (MAPK inhibitor) or chelerythrine (protein kinase C (PKC) inhibitor) before Pg or MPA treatment, the former totally suppressed the steroid action, but the PKC antagonist did not affect NO production. In the presence of a PI3K inhibitor (LY294002), a partial reduction in Pg effect and a reversal of MPA action were detected. Using indomethacin, the contribution of the cyclooxygenase (COX) pathway was also detected. On platelet adhesion assays, Pg inhibited and MPA stimulated platelet adhesion to ECs. Under inflammatory conditions, Pg prevented platelet adhesion induced by lipopolysaccharide (LPS); meanwhile, MPA potentiated the stimulatory action of LPS. Finally, although both steroids enhanced migration of ECs, MPA exhibited a greater effect. In conclusion, the data presented in this research provide evidence of a differential regulation of vascular function by Pg and MPA.
Opposing Activities of DRM and MES-4 Tune Gene Expression and X-Chromosome Repression inCaenorhabditis elegansGerm Cells
Authors: Tabuchi Tomoko M , Rechtsteiner Andreas , Strome Susan , Hagstrom Kirsten A
Published: December 2013

During animal development, gene transcription is tuned to tissue-appropriate levels. Here we uncover antagonistic regulation of transcript levels in the germline of Caenorhabditis elegans hermaphrodites. The histone methyltransferase MES-4 (Maternal Effect Sterile-4) marks genes expressed in the germline with methylated lysine on histone H3 (H3K36me) and promotes their transcription; MES-4 also represses genes normally expressed in somatic cells and genes on the X chromosome. The DRM transcription factor complex, named for its Dp/E2F, Retinoblastoma-like, and MuvB subunits, affects germline gene expression and prevents excessive repression of X-chromosome genes. Using genome-scale analyses of germline tissue, we show that common germline-expressed genes are activated by MES-4 and repressed by DRM, and that MES-4 and DRM co-bind many germline-expressed genes. Reciprocally, MES-4 represses and DRM activates a set of autosomal soma-expressed genes and overall X-chromosome gene expression. Mutations in mes-4 and the DRM subunit lin-54 oppositely skew the transcript levels of their common targets and cause sterility. A double mutant restores target gene transcript levels closer to wild type, and the concomitant loss of lin-54 suppresses the severe germline proliferation defect observed in mes-4 single mutants. Together, “yin-yang” regulation by MES-4 and DRM ensures transcript levels appropriate for germ-cell function, elicits robust but not excessive dampening of X-chromosome-wide transcription, and may poise genes for future expression changes. Our study reveals that conserved transcriptional regulators implicated in development and cancer counteract each other to fine-tune transcript dosage.
Alterações morfoanatômicas foliares da cana-de-açúcar na fase de estabelecimento em condições de matocompetição
Authors: Figueiredo P.A.M. , Ramos S.B. , Viana R.S. , Lisboa L.A.M. , Heinrichs R.
Published: December 2013

Com o objetivo de avaliar parâmetros de produção e possíveis alterações morfoanatômicas de tecidos foliares da cana-de-açúcar, variedade RB 86 7515, na fase de estabelecimento, em condições de matocompetição, foi conduzido um experimento em vasos em Dracena, Estado de São Paulo, entre os meses de abril e junho de 2010, na Universidade Estadual Paulista Júlio de Mesquita Filho. Foram utilizadas as espécies Brachiaria brizantha e Brachiaria decumbens, consideradas como invasoras. Foi utilizado o delineamento inteiramente casualizado, sendo sete tratamentos e cinco repetições, totalizando 35 parcelas ou vasos. Os tratamentos variaram de acordo com o número de sementes de Brachiaria brizantha e Brachiaria decumbens, sendo: T1 - ausência de matocompetição; T2 - baixa ocorrência de matocompetição com Brachiaria brizantha; T3 - média ocorrência de matocompetição com Brachiaria brizantha; T4 - alta ocorrência de matocompetição com Brachiaria brizantha; T5 - baixa ocorrência de matocompetição com Brachiaria decumbens; T6 - média ocorrência de matocompetição com Brachiaria decumbens; e T7 - alta ocorrência de matocompetição com Brachiaria decumbens. Após 60 dias do plantio da cana-de-açúcar e das espécies invasoras, foram avaliados: peso da matéria seca total das plantas; espessura da epiderme da face superior ou adaxial; espessura da epiderme da face inferior ou abaxial; espessura do mesofilo; espessura do limbo; diâmetro dos vasos xilemáticos; e diâmetro dos vasos floemáticos. A matocompetição das espécies Brachiaria brizantha e Brachiaria decumbens, consideradas como invasoras, provocou redução das características morfoanatômicas e de produção da cana-de-açúcar. De maneira geral, Brachiaria decumbens foi a espécie que mais influenciou negativamente a espessura foliar da cana-de-açúcar.
Accumulation of dry mass and macronutrients by sourgrass plants
Authors: Carvalho L.B. , Bianco M.S. , Bianco S.
Published: December 2013

The experiment was carried out aiming to analyze the dry mass production and distribution and the content and accumulation of macronutrients in sourgrass (Digitaria insularis) plants cultivated under mineral nutrition standard conditions. Plants grew in 7-liter pots filled with sand substrate and daily irrigated with nutrient solution, being maintained under greenhouse conditions. Treatments consisted of times of evaluation (21, 35, 49, 63, 77, 91, 105, 119, and 133 days after emergence - DAE) and were arranged in a completely randomized design with four replicates. Sourgrass showed small accumulation of dry mass (0.3 g per plant) and macronutrients (3.7 mg of N per plant, 0.4 mg of P per plant, 5.6 mg of K per plant, 0.9 mg of Ca per plant, 0.7 mg of Mg per plant, and 0.3 mg of S per plant) at vegetative growth stage (< 49 DAE). Those accumulations increased mainly after 77 DAE, reaching the maximum theoretical value at 143, 135, 141, 129, 125, 120, and 128 DAE, for dry mass (12.4 g per plant), N (163.2 mg per plant), P (27.1 mg per plant), K (260.5 mg per plant), Ca (47.6 mg per plant), Mg (30.9 mg per plant), and S (13.7 mg per plant), respectively. K and N were found with higher rates and, as a consequence, they were required and accumulated in greater amounts in plant tissues of sourgrass.
Initial growth and competitive ability of yellow nutsedge and irrigated rice
Authors: Westendorff N.R. , Agostinetto D. , Ulguim A.R. , Langaro A.C. , Thürmer L.
Published: December 2013

Weeds cause significant reduction in the irrigated rice crop yield. Cyperus esculentus (yellow nutsedge) is adapted to irrigate environment. Information on the competitive ability of the weed to the culture, and their environmental adaptation, are scarce. In this study, we sought to determine the initial growth and competitive ability of yellow nutsedge and irrigated rice, as a function of cultivar growth cycle. Initial growth and competition studies were conducted in a randomized complete design in a greenhouse in the agricultural year 2010/11. For the initial growth study, the treatments consisted of a factorial combination of a biotype of yellow nutsedge and two rice cultivars in the function of the vegetative cycle (BRS Querência: early cycle - IRGA 424: intermediate cycle) and six evaluation times (10, 20, 30, 40, 50, and 60 days after emergence). Were evaluated: plant height, leaf area, aboveground dry biomass and root dry biomass. In the competitive ability study in the replacement series, the cultivar BRS Querência (early cycle) and yellow nutsedge were utilized and tested in different proportions of competition (100:0, 75:25, 50:50, 25:75, and 0:100). Were evaluated leaf area and aboveground dry biomass. In general, rice cultivars have an adaptive value equivalent to yellow nutsedge. IRGA 424 cultivar has less height than weed, becoming the weed control more important in this cultivar. For rice crop, intraspecific competition is more important, whereas for the weed, interspecific competition is the most pronounced.
Nível crítico de dano de papuã em feijão-comum
Authors: Kalsing A. , Vidal R.A.
Published: December 2013

Os objetivos do presente trabalho foram estimar níveis críticos de dano de papuã (Urochloa plantaginea) em feijão-comum, em situações onde a planta daninha foi manejada precocemente e ocorreu reinfestação, e avaliar as alterações que sofre em decorrência de cultivares de feijão-comum e variáveis explicativas da infestação. Foram realizados dois experimentos em campo, em Eldorado do Sul, RS, sendo um com o cultivar UFT-06 (grupo Carioca) e o outro com o cultivar IPR Graúna (grupo Preto). Os níveis de infestação de papuã foram obtidos com quatro herbicidas residuais, aplicados em duas doses cada, mais testemunhas com e sem controle de papuã. A densidade, massa fresca e massa seca do papuã foram avaliadas no início e no final do período crítico de prevenção da interferência, e o rendimento de grãos da cultura foi avaliado por ocasião da colheita. O nível crítico de dano de papuã não teve valor elevado nessa situação (0,4 a 0,7%); todavia, pode haver benefício em controlá-lo de acordo com a infestação e o custo de controle. O nível crítico de dano foi sempre maior para o cultivar IPR Graúna, em relação ao UTF-06. A densidade e as massas fresca e seca das plantas de papuã explicaram adequadamente a perda de produção de feijão-comum pelo modelo de regressão não linear da hipérbole retangular.
Adaptive value of ryegrass biotypes with low-level resistance and susceptible to the herbicide fluazifop and competitive ability with the wheat culture
Authors: Fraga D.S. , Agostinetto D. , Vargas L. , Nohatto M.A. , Thürmer L. , Holz M.T.
Published: December 2013

Ryegrass is the main weed in wheat crop, causing yield loss due to competition by environmental resources. The objectives of this study were to estimate the fitness cost of ryegrass biotypes with low-level resistance and susceptible to fluazifop and to investigate the relative competitive ability of these biotypes between themselves and against the crop. Thus, fitness cost and competitive ability experiments were conducted under greenhouse conditions. For the fitness cost experiments, the low-level resistant ryegrass biotypes and those susceptible to fluazifop were used. For competitive ability, the treatments were arranged in a replacement series, with five proportions of the wheat cultivar FUNDACEP Horizonte and the low-level resistant and susceptible ryegrass biotypes 100:0, 75:25, 50:50, 25:75 and 0:100. Competitive analysis was carried out through diagrams applied to the replacement experiments and use of relative competitiveness indices. Variables evaluated were plant height, in the fitness cost experiment, and leaf area and shoot dry biomass in both experiments. The ryegrass biotypes show overall similar fitness cost and competitive ability. The wheat cultivar FUNDACEP Horizonte is superior in competitive ability to the ryegrass biotype with low-level resistance and equivalent to the susceptible biotype.
Dose-response curves of Lolium multiflorum biotypes resistant and susceptible to clethodim
Authors: Vargas L. , Fraga D.S. , Agostinetto D. , Mariani F. , Duarte T.V. , Silva B.M.
Published: December 2013

Chemical control with herbicides, especially glyphosate, is the main method used to control ryegrass. However, the repeated use of glyphosate has selected resistant ryegrass biotypes. Thus, the ACCase inhibitor herbicides have become the main alternative to control glyphosate-resistant biotypes, being widely used by farmers in Rio Grande do Sul. Repeated use of ACCase inhibitors, in turn, have selected ryegrass biotypes resistant to this herbicide mechanism. Thus, the objective of this study was to evaluate the response of ryegrass biotypes to different clethodim rates by dose-response curves. Increasing doses (0, 12, 24, 48, 72, 96, 144 and 192 g a.i. ha-1) of the herbicide clethodim were applied at the 3-4 ryegrass leaf stage. The variables control at 14 and 28 days after treatment (DAT) and shoot dry weight were evaluated. The data were fitted by nonlinear regression log-logistic and C50 and GR50 were calculated based on the equation. The resistance factor was obtained by the ratio of C50 or GR50 of the resistant biotype by matching the susceptible biotype. Based on the equation parameters, the doses of GR50 64.7 and 234.5 g a.i. ha-1 clethodim and C50 11.2 and 172.1 g a.i. ha-1 clethodim were obtained, at 28 DAT for the susceptible and resistant biotypes, respectively. The ryegrass biotype denominated Cotril is resistant to clethodim, being controlled with a dose 15.3 times greater than that of the susceptible biotype, and a 50% reduction of this biotype occurs with a dose 3.62 times higher than that of the susceptible one.
Herbicide selectivity in alfalfa crops
Authors: Hijano N. , Monquero P.A. , Munhoz W.S. , Gusmão M.R.
Published: December 2013

This study aimed to determine the selectivity of herbicides applied in pre- and post-emergence for alfalfa crops. Three separate experiments were carried out under greenhouse conditions. The first experiment was arranged in a completely randomized design with three replications in a 4 x 11 + 1 factorial scheme , with eleven herbicides (bentazon, chlorimuron-ethyl, fomesafen, fluazifop-p-butyl, saflufenacil, imazethapyr, clethodim, nicosulfuron, imazaquin, haloxyfop-methyl and MSMA), four doses of each herbicide (0.5 D, 0.75 D, 1.0 D and 1.25 D, where D = recommended dose), plus an untreated control. The products were applied to alfalfa plants at the stage of 4 to 5 leaf pairs. In the second experiment, the effect of pre-emergent herbicides on early alfalfa development was observed through a completely randomized design with five replications in a 3 x 4 x 2 factorial scheme, with three herbicides (hexazinone, atrazine + simazine, S-metolachlor), four doses (0.5 D, 0.75 D, 1.0 D and 1.25 D), and two types of soil texture (loamy and clay soil), plus an untreated control. The third experiment evaluated the action of atrazine, 2,550 g ha-1; clomazone - 600 g ha-1; diclosulam - 25 g ha-1; diuron+hexazinone - 936 + 264 g ha-1 and diuron+hexazinone +sulfometuron - 1,386 + 391 + 33.35 g ha-1 on alfalfa sown at different times after herbicide application. The effects of the treatments on alfalfa were evaluated according to visual phytotoxicity symptoms, plant height, and biomass of roots and shoots. Among the herbicides applied at post-emergence, imazethapyr, clethodim, haloxyfop-p-methyl and MSMA were selective for alfalfa, while among those applied at pre-emergence, none were selective, regardless of soil texture. The results of the third experiment showed that the herbicides diclosulam, hexazinone + diuron and atrazine caused less toxicity in alfalfa plants.
Reduction of seed production of red rice escapes in clearfield rice
Authors: Menezes V.G. , Kalsing A. , Mariot C.H.P. , Grohs D.S. , Freitas T.F.S.
Published: December 2013

Roguing is a practice used to reduce the seed source of red rice escapes to control in Clearfield-rice areas. However, there is great difficulty in performing it in large and heavily infested rice fields. This objective of this work was to evaluate the effects of the use of imazamox herbicide, applied in different rates and times, on plants of Clearfield-rice and red rice. Four experiments were conducted during the 2007/08 and 2008/09 growing seasons, in completely randomized block design and treatments arranged in factorial design, using three replications per treatment. The treatments had increasing rates of imazamox, application times and rice cultivars. The rice cultivars tested were IRGA 417, IRGA 422 CL, Avaxi CL and Puitá INTA CL. The variables evaluated were the number of panicles m-2, number of grains panicle-1, spikelet sterility in rice and red rice; and, rice grain yield and its components. The imazamox reduced the seed production of red rice escapes in a simulated situation of commercial Clearfield-rice area. The greater percentage reductions were obtained when this herbicide was applied at final formation of the panicle or panicle exertion of the red rice plant escapes to control. The Puitá INTA CL cultivar has high level of resistance to imazamox, independent of rate and application times tested, becoming the only alternative to the use of this practice.
Brasil na governança global do clima, 2005-2012: a luta entre conservadores e reformistas
Authors: Viola Eduardo , Franchini Matías
Published: December 2013

A área de governança global do clima é definida por dois vetores básicos: poder e compromisso climático. O primeiro faz referência ao impacto de certos atores com capacidades suficientes para influenciar o social outcome climático. O segundo considera como a lógica da governança na área é definida pela dialética entre forças que assimilam o problema climático como crise civilizatória - reformistas - e forças que resistem às transformações necessárias para estabilizar o sistema climático - conservadoras. Neste artigo, usamos essas duas categorias para responder a pergunta sobre o papel do Brasil na estrutura de governança global de clima, e afirmamos que, a partir de meados da década passada, o país atravessou um processo de mudanças que o levou da condição de uma grande potência conservadora para uma posição de conservadorismo moderado. Essa transição se sustentou em três pilares básicos, diferentes: a trajetória decrescente das emissões de gases de efeito estufa (GEE), a adoção de políticas climáticas domésticas e a mudança do perfil internacional de negociação. No entanto, a partir de 2011, o impulso reformista foi desacelerando e finalmente estagnou. O objetivo deste artigo é abordar essa transformação - drástica e inesperada - e avaliar suas perspectivas - na medida em que é inconclusa é incerta.
Governos subnacionais amazônicos: novos padrões de relacionamento na conjuntura internacional contemporânea
Authors: Moreira Paula Gomes
Published: December 2013

Ao contrário das pesquisas em torno da paradiplomacia dos estados do Sul do Brasil, sobre a qual já existe uma significativa bibliografia, são limitados os textos que tratam da maior atuação de entes subnacionais no espaço amazônico. O presente artigo introduz essa discussão através de dois eixos principais, notadamente, a maior inserção de governos estaduais e municipais em temas internacionais a partir do aprofundamento da globalização e o relacionamento desses novos agentes com o Itamaraty e a Presidência da República. Dessa forma, pretende-se contribuir para a ampliação da agenda de discussão sobre o tema entre os pesquisadores da área, além de apresentar panoramas recentes da arte da paradiplomacia nos estados fronteiriços amazônicos, mais especificamente, Acre, Amazonas, Amapá, Pará, Roraima e Rondônia.
Através dos olhos do dragão: um estudo sobre o campo das Relações Internacionais na China
Authors: Leite Alexandre César Cunha , Máximo Jéssica Cristina Resende
Published: December 2013

Este trabalho procura apresentar o desenvolvimento recente do campo de Relações Internacionais na China, através de uma revisão bibliográfica crítica de obras sobre o desenvolvimento dos estudos de RI na China e de obras chinesas acerca das relações internacionais. Dessa forma, busca-se delinear a história da evolução do campo por meio da análise do contexto intelectual, social, econômico e político no qual o mesmo se desenvolveu. Não obstante, são abordados os principais temas de pesquisa e orientações teóricas chinesas, assim como contribuições nativas próprias para a teorização no campo.
A economia política dos Fundos de Riqueza Soberana
Authors: Arienti Patricia Fonseca Ferreira , Viera Luan
Published: December 2013

Os Fundos de Riqueza Soberana (FRS) são novos atores dentro do atual regime monetário e financeiro internacional. A atuação dos FRS representa o retorno da participação do Estado no sistema financeiro internacional, o que levanta vários questionamentos quanto aos verdadeiros objetivos desses fundos, ou seja, se os fundos atuam em busca de lucro ou por motivos políticos-estratégicos. O objetivo do artigo é analisar se a ausência de uma regulamentação internacional à atuação dos FRS pode ser entendida dentro da concepção de regimes internacionais ou deve ser pensada a partir das relações de interesses entre os diferentes Estados.
Conhecimento e prática de acadêmicos de enfermagem sobre cuidados com portadores de feridas
Authors: Ferreira Adriano Menis , Rigotti Marcelo Alessandro , Pena Silvana Barbosa , Paula Dioner da Silva , Ramos Iara Barbosa , Sasaki Vanessa Damiana Menis
Published: December 2013

O presente estudo teve como objetivo identificar o conhecimento, a prática e fontes de informações de graduandos de enfermagem sobre o cuidado a portadores de feridas. Trata-se de estudo quantitativo com delineamento descritivo-exploratório realizado com 68 graduandos de enfermagem do 9º período de uma Universidade Pública do estado de Mato Grosso do Sul. A coleta foi realizada com duas turmas nos anos de 2008 e 2009. Os dados foram coletados por um questionário adaptado e validado. Somente 6 (54,5%) itens alcançaram acertos acima de 50%. Desses, 4 (36,3%) não chegaram a 70% de acertos. Apenas 2 (11,1%) itens foram respondidos corretamente por todos os acadêmicos. Constatou-se que a maioria dos acadêmicos não utiliza fontes de informações para atualização sobre o assunto. Os resultados demonstraram que o nível de conhecimento sobre o cuidado a portadores de feridas é baixo e, portanto, investimentos no ensino de graduação do referido curso são necessários.
Orthodontic movement of endodontically treated teeth
Authors: Consolaro Alberto , Consolaro Renata Bianco
Published: December 2013

Often there is the need of moving teeth endodontically treated or teeth still in endodontic treatment. In order to collaborate with the comprehension and substantiation of the following subjects will be discussed: 1) Orthodontic movement in endodontically treated teeth without periapical lesion, 2) Orthodontic movement in endodontically treated teeth with inflammatory periapical lesion, and 3) Orthodontic movement in teeth endodontically treated due to aseptic pulp necrosis by dental trauma. In practically all situations, endodontically treated teeth to be orthodontically moved must be subjected to a careful evaluation by the endodontist about the conditions, adequate or not, of the endodontic treatment. Then, in this paper it was sought to induce an insight for new clinical researches about the theme that may definitely prove the information obtained by interrelations of information in parallel to clinical practice.
Fixed Lingual Mandibular Growth Modificator: a new appliance for Class II correction
Authors: Alali Osama Hasan
Published: December 2013

INTRODUCTION: This article demonstrates the description and use of a new appliance for Class II correction. MATERIAL AND METHODS: A case report of a 10-year 5 month-old girl who presented with a skeletally-based Class II division 1 malocclusion (ANB = 6.5º) on a slightly low-angle pattern, with ML-NSL angle of 30º and ML-NL angle of 22.5º. Overjet was increased (7 mm) and associated with a deep bite. RESULTS: Overjet and overbite reduction was undertaken with the new appliance, Fixed Lingual Mandibular Growth Modificator (FLMGM). CONCLUSION: FLMGM may be effective in stimulating the growth of the mandible and correcting skeletal Class II malocclusions. Clinicians can benefit from the unique clinical advantages that FLMGM provides, such as easy handling and full integration with bracketed appliance at any phase.
Comparison of shear bond strength of orthodontics brackets on composite resin restorations with different surface treatments
Authors: Ribeiro Alexandre Antonio , Morais Ariane Vicente de , Brunetto Daniel Paludo , Ruellas Antonio Carlos de Oliveira , Araujo Monica Tirre Souza de
Published: December 2013

INTRODUCTION: Orthodontic patients frequently present composite resin restorations, however there are few studies that evaluate the best way for orthodontic bonding in this situation. OBJECTIVE: The objective of this work was to evaluate the bond strength of orthodontic brackets in resin restorations with surface treatment. METHODS: Fifty one bovine lower incisors were randomly divided into three groups. On the control group (CG) the brackets were bonded to dental enamel; on experimental groups, brackets were bonded to resin restoration with diamond drill treatment (EGT) and with no treatment (EGN). The teeth were placed in PVC tubes with autopolymerized acrylic resin. The shear test was performed in EMIC universal testing machine. The groups were submitted to ANOVA analysis of variance with Tukey post test to verify the statistical difference between groups (α = 0.05). RESULTS: CG (6.62 MPa) and EGT (6.82 MPa) groups presented similar results, while EGN (5.07 MPa) obtained statistically lower results (p < 0.05). CONCLUSION: Therefore, it is concluded that the best technique for bonding of orthodontic brackets on composite resin restorations is the performance of surface detritions.
Occlusal assessment in surgically assisted unilateral cleft lip and palate patients
Authors: Leal Leanne Matias Portela , Rego Marcus Vinicius Neiva Nunes do , Silva Filho Cosme José Albergaria da , Capelozza Filho Leopoldino , Cardoso Mauricio de Almeida
Published: December 2013

OBJECTIVE: The aim of this study was to assess the magnitude of occlusal changes in individuals with unilateral cleft lip and palate (CLP). The study was conducted on study casts of 25 subjects, 14 men and 11 women aged from 7 to 20 years, without previous orthodontic treatment and with surgical repair carried out at São Marcos Hospital, Teresina, Piauí State, Brazil. METHODS: The casts were assessed by three orthodontists based on the occlusal scores established by Atack et al., whose scores range from 1 to 5, according to the magnitude of transverse and sagittal changes. RESULTS: Intra and inter-observer reproducibility of occlusal scores was satisfactory and statistically significant according to the Spearman Correlation test with significance level set at 5%. With regard to the distribution of occlusal scores, 30.67% of the subjects achieved scores 1 and 2, 22% score 3 and 47.53% achieved scores 4 and 5. CONCLUSIONS: Four was the score most frequently assigned by the observers, disclosing a high degree of transverse and sagittal disorders in the occlusion of patients.
Mohr–Coulomb failure envelopes of lime-treated soils
Authors: CONSOLI N.C. , DA SILVA LOPES JR L. , CONSOLI B.S. , FESTUGATO L.
Published: December 2013

The aim of this study is to quantify the influence of amount of lime and porosity in the assessment of the Mohr–Coulomb failure envelope of lime-treated soils based on unconfined compressive strength (σc) and splitting tensile strength (σt) of such materials, without the necessity of carrying out triaxial testing. Based on a previously established concept that the σt/σc relationship is unique for each specific fine-grained soil and lime blend, it is shown that the effective angle of shearing resistance of a given lime-treated soil is independent of the porosity and the amount of lime of the specimen and that effective cohesion intercept is a direct function of σc (or σt) of the improved soil; this in turn depends on the porosity and volumetric amount of lime in the soil–lime blends. Finally, the concepts are successfully tested for clayey sand treated with lime at two distinct curing time periods, considering weak to moderate cementation levels.
Estimating Scale Deposition Through Reservoir History Matching in the Janice Field
Authors: Vazquez Oscar , Young Callum , Demyanov Vasily , Arnold Dan , Fisher Andrew , MacMillan Alasdair , Christie Mike
Published: December 2013

Inorganic-scale precipitation and deposition in production wells can be a significant impediment to effective reservoir management. In extreme cases, scale can cause the well to be abandoned as a result of reservoir-formation damage in the near-wellbore region and the narrowing of the production-tubing annulus, thus preventing fluid flow. The prediction of the time and location of scale formation is therefore essential for scale management. This study is focused on sulfate scales, which form when sulfate-rich seawater mixes with formation brines that are rich in barium, calcium, and strontium, and which are among the most difficult types of scale to prevent and remove.

Formation brines in reservoirs with a tendency for sulfate-scale deposition can have a very different makeup when compared with seawater, which may be injected for pressure support. Having such different chemistries allows seawater and formation brine to be tracked. In this study, two different types of water are considered: formation brine and injected seawater.

The objective of this work is to predict uncertainty in sulfate-scale deposition from multiple history-matched reservoir models by tracking injected seawater in the Janice field. There are many examples in the literature in which conventional reservoir history matching (namely, gas rate, oil rate, and bottomhole pressure) are used to generate an ensemble of good history-matched models that will estimate uncertainty of a hydrocarbon-reservoir production. In this study, the same approach will be adopted, but including produced-water chemistry—in particular, seawater breakthrough. This approach provides a methodology to predict the uncertainty of the formation-brine/injected-seawater mixing zone within the reservoir formation. The methodology provides a Bayesian confidence interval (P10/P50/P90) in time and space for the injected seawater, identifying which wells will be at risk on the basis of seawater breakthrough and in which zones of the reservoir mixing is more likely to occur.