bluuebunny/crossref_metadata_2025 huggingface dataset:
A Caspase Cascade Regulating Developmental Axon Degeneration
Authors: Simon David J. , Weimer Robby M. , McLaughlin Todd , Kallop Dara , Stanger Karen , Yang Jing , O'Leary Dennis D. M. , Hannoush Rami N. , Tessier-Lavigne Marc
Published: December 2012

Axon degeneration initiated by trophic factor withdrawal shares many features with programmed cell death, but many prior studies discounted a role for caspases in this process, particularly Caspase-3. Recently, Caspase-6 was implicated based on pharmacological and knockdown evidence, and we report here that genetic deletion ofCaspase-6indeed provides partial protection from degeneration. However, we find at a biochemical level that Caspase-6 is activated effectively only by Caspase-3 but not other “upstream” caspases, prompting us to revisit the role of Caspase-3.In vitro, we show that genetic deletion ofCaspase-3is fully protective against sensory axon degeneration initiated by trophic factor withdrawal, but not injury-induced Wallerian degeneration, and we define a biochemical cascade from prosurvival Bcl2 family regulators to Caspase-9, then Caspase-3, and then Caspase-6. Only low levels of active Caspase-3 appear to be required, helping explain why its critical role has been obscured in prior studies.In vivo,Caspase-3andCaspase-6-knockout mice show a delay in developmental pruning of retinocollicular axons, thereby implicating both Caspase-3 and Caspase-6 in axon degeneration that occurs as a part of normal development.
Distinct Modifications in Kv2.1 Channel via Chemokine Receptor CXCR4 Regulate Neuronal Survival-Death Dynamics
Authors: Shepherd Andrew J. , Loo Lipin , Gupte Raeesa P. , Mickle Aaron D. , Mohapatra Durga P.
Published: December 2012

The chemokine stromal cell-derived factor-1α (SDF-1α) has multiple effects on neuronal activity, survival, and death under conditions that generate a proinflammatory microenvironment within the brain, via signaling through C-X-C-type chemokine receptor 4 (CXCR4), although the underlying cellular/molecular mechanisms are unclear. Using rat hippocampal neurons, we investigated distinct modifications in the voltage-gated K+(Kv) channel Kv2.1 in response to short- and long-term SDF-1α/CXCR4-mediated signaling as an underlying mechanism for CXCR4-dependent regulation of neuronal survival and death. Acute exposure of neurons to SDF-1α led to dynamic dephosphorylation and altered localization of Kv2.1 channel, resulting in enhanced voltage-dependent activation of Kv2.1-based delayed-rectifier Kv currents (IDR). These changes were dependent on CXCR4- and/or NMDA receptor-mediated activation of calcineurin and provide neuroprotection. However, prolonged SDF-1α treatment leads to CXCR4-mediated activation of p38 mitogen-activated protein kinase, resulting in phosphorylation of Kv2.1 at S800 and enhanced surface trafficking of the channel protein, resulting in increasedIDR/Kv2.1 current density. This, in combination with sustained dephosphorylation-induced enhancement of the voltage-dependent activation ofIDR/Kv2.1, predisposed neurons to excessive K+efflux, a vital step for the neuronal apoptotic program. Such apoptotic death was dependent on CXCR4 and Kv2.1 function and was absent in cells expressing the Kv2.1–S800A mutant channel. Furthermore, similar modifications in Kv2.1 and CXCR4/Kv2.1-dependent apoptosis were observed following treatment of neurons with the human immunodeficiency virus-1 (HIV-1) glycoprotein gp120. Therefore, distinct modifications in Kv2.1 in response to short- and long-term CXCR4-mediated signaling could provide a basis for neuroprotection or apoptosis in neuropathologies, such as neuroinflammation, stroke, brain tumors, and HIV-associated neurodegeneration.
Topographic Distribution, Frequency, and Intensity Dependence of Stimulus-Specific Adaptation in the Inferior Colliculus of the Rat
Authors: Duque Daniel , Pérez-González David , Ayala Yaneri A. , Palmer Alan R. , Malmierca Manuel S.
Published: December 2012

The ability to detect unexpected sounds within the environment is an important function of the auditory system, as a rapid response may be required for the organism to survive. Previous studies found a decreased response to repetitive stimuli (standard), but an increased response to rare or less frequent sounds (deviant) in individual neurons in the inferior colliculus (IC) and at higher levels. This phenomenon, known as stimulus-specific adaptation (SSA) has been suggested to underpin change detection. Currently, it is not known how SSA varies within a single neuron receptive field, i.e., it is unclear whether SSA is a unique property of the neuron or a feature that is frequency and/or intensity dependent. In the present experiments, we used the common SSA index (CSI) to quantify and compare the degree of SSA under different stimulation conditions in the IC of the rat. We calculated the CSI at different intensities and frequencies for each individual IC neuron to map the neuronal CSI within the receptive field. Our data show that high SSA is biased toward the high-frequency and low-intensity regions of the receptive field. We also find that SSA is better represented in the earliest portions of the response, and there is a positive correlation between the width of the frequency response area of the neuron and the maximum level of SSA. The present data suggest that SSA in the IC is not mediated by the intrinsic membrane properties of the neurons and instead might be related to an excitatory and/or inhibitory input segregation.
Glutamate Receptor 1 Phosphorylation at Serine 831 and 845 Modulates Seizure Susceptibility and Hippocampal Hyperexcitability after Early Life Seizures
Authors: Rakhade Sanjay N. , Fitzgerald Erin F. , Klein Peter M. , Zhou Chengwen , Sun Hongyu , Huganir Richard L. , Jensen Frances E.
Published: December 2012

Neonatal seizures can lead to later life epilepsy and neurobehavioral deficits, and there are no treatments to prevent these sequelae. We showed previously that hypoxia-induced seizures in a neonatal rat model induce rapid phosphorylation of serine-831 (S831) and Serine 845 (S845) sites of the AMPA receptor GluR1 subunit and later neuronal hyperexcitability and epilepsy, suggesting that seizure-induced posttranslational modifications may represent a novel therapeutic target. To unambiguously assess the contribution of these sites, we examined seizure susceptibility in wild-type mice versus transgenic knock-in mice with deficits in GluR1 S831 and S845 phosphorylation [GluR1 double-phosphomutant (GluR1 DPM) mice]. Phosphorylation of the GluR1 S831 and S845 sites was significantly increased in the hippocampus and cortex after a single episode of pentyleneterazol-induced seizures in postnatal day 7 (P7) wild-type mouse pups and that transgenic knock-in mice have a higher threshold and longer latencies to seizures. Like the rat, hypoxic seizures in P9 C57BL/6N wild-type mice resulted in transient increases in GluR1 S831 and GluR1 S845 phosphorylation in cortex and were associated with enhanced seizure susceptibility to later-life kainic-acid-induced seizures. In contrast, later-life seizure susceptibility after hypoxia-induced seizures was attenuated in GluR1 DPM mice, supporting a role for posttranslational modifications in seizure-induced network excitability. Finally, human hippocampal samples from neonatal seizure autopsy cases also showed an increase in GluR1 S831 and S845, supporting the validation of this potential therapeutic target in human tissue.
Unequal New Democracies in East Asia: Rising Inequality and Government Responses in South Korea and Taiwan
Authors: Chi Eunju , Kwon Hyeok Yong
Published: December 2012

This paper explores the growing trend in income inequality in Korea and Taiwan. The two recent East Asian democracies have witnessed rising inequality since the 1990s but with cross-national differences. We find that market inequality is higher in Taiwan than in Korea, yet the Taiwan government’s efforts to reduce this disparity are stronger than similar moves in Korea. By applying the logic of economic, social, and political effects, we find both similar trends and divergent paths in the politics of inequality in the two countries.
Usefulness of salivary cortisol in the diagnosis of hypercortisolism: comparison with serum and urinary cortisol
Authors: Manetti Luca , Rossi Giuseppe , Grasso Lucia , Raffaelli Valentina , Scattina Ilaria , Del Sarto Simone , Cosottini Mirco , Iannelli Aldo , Gasperi Maurizio , Bogazzi Fausto , Martino Enio
Published: December 2012

Objective

Several tests have been proposed to diagnose patients with Cushing's syndrome (CS). The aims of the study were: i) to evaluate the performance of salivary cortisol (SC) in hypercortisolism and ii) to compare SC with serum cortisol (SeC) and urinary cortisol.

Design and patients

This was a diagnostic study. Twenty-seven patients with untreated Cushing's disease (CD untr), 21 women consuming oral contraceptive pill (OCP), 18 pregnant women, and 89 healthy subjects (controls) were enrolled.

Methods

SC and SeC at baseline and after the low-dose dexamethasone suppression test (LDDST) and urinary free cortisol (UFC) were measured.

Results

Midnight SC had a sensitivity of 100% in the CD untr group and a specificity of 97.7% in the controls. Specificity remained high (95.2%) in women taking OCP, while in pregnant women, it decreased to 83.3%. SC after the LDDST showed a sensitivity of 96.3% in the CD untr group; specificity was 97.7% in the controls and 90.5% in OCP women. Midnight SeC had a sensitivity of 100% in the CD untr group. SeC after the LDDST had a sensitivity of 100% in the CD untr group while specificity was 97.7% in the controls and 61.9% in women taking OCP. For UFC, sensitivity was 92.6% in the CD untr group while specificity was 97.7% in the controls and 100% in the OCP group.

Conclusions

SC is a reliable parameter for the diagnosis of severe hypercortisolism, with high sensitivity and specificity. In women during pregnancy or taking OCP, the measurement of SC, identifying the free fraction, could be helpful to exclude CS.
Molecular epidemiology of multiple endocrine neoplasia 2: implications for RET screening in the new millenium
Authors: Machens Andreas , Lorenz Kerstin , Sekulla Carsten , Höppner Wolfgang , Frank-Raue Karin , Raue Friedhelm , Dralle Henning
Published: December 2012

Objective

Twenty years ago, the groundbreaking discovery that rearranged during transfection (RET) mutations underlie multiple endocrine neoplasia 2 (MEN2) and familial medullary thyroid cancer (FMTC) ushered in the era of personalized medicine. MEN2-associated signs, taking time to manifest, can be subtle. This study sought to clarify to what extent conventional estimates of 1:200 000–500 000 underestimate the incidence ofRETmutations in the population.

Design

Included in this retrospective investigation were 333 RET carriers born between 1951 and 2000 and operated on at the largest German surgical referral center (286 carriers) or elsewhere (47 carriers).

Methods

To estimate the incidence ofRETmutations, the number of RET carriers born in Germany in five decades (1951–1960, 1961–1970, 1971–1980, 1981–1990, and 1991–2000) was divided by the corresponding number of German live births.

Results

Owing to improved diagnosis and capture of FMTC and MEN2 patients, minimum incidence estimates increased over time: overall from 5.0 (1951–1960) to 9.9 (1991–2000) per million live births and year (P=0.008), and by American Thyroid Association/ATA class from 1.7 to 3.7 for ATA class C (P=0.008); from 1.8 to 2.7 for ATA class A (P=0.017); from 1.5 to 2.2 for ATA class B (P=0.20); and from 0 to 1.4 for ATA class D mutations per million live births and year (P=0.008). Based on 1991–2000 incidence estimates the prevalence in Germany is ∼1:80 000 inhabitants.

Conclusions

The molecular minimum incidence estimate of ≈1:100 000 was two- to fivefold greater than conventional estimates of 1:200 000–500 000.
Nondestructive Evaluation of Fatigue Limit of Metals using Infrared Thermography
Authors: Luong M. P.
Published: December 2012

The paper aims to illustrate three advantages of infrared thermography as a non-destructive, real-time and non-contact technique. It permits first observation of the macrostructural aspects of thermoplasticity describing damage and failure processes in metals, and in particular, automotive components subjected to fatigue loading, second detection of the occurrence of intrinsic dissipation, and third evaluation of the fatigue strength in a very short time, compared to traditional fatigue testing techniques. In addition, infrared thermography readily describes the damage location and the evolution of structural failure.
High Frequency Electron Spin Resonance Study of Hydrogenated Microcrystalline Silicon
Authors: Ehara Takashi
Published: December 2012

Dangling bond defects (DB) in hydrogenated microcrystalline silicon (μc-Si:H) have been studied by X-band (9 GHz) Q-band (33 GHz) and W-band (90 GHz) electron spin resonance (ESR) spectroscopy. In X-band ESR spectra, all the samples showed asymmetric dangling bond defect signal at g = 2.005 – 2.006. The DB signal shape shows little dependence on substrate temperature in the X-band electron spin resonance (ESR) spectra. In the Q-band and W-band ESR spectra, existence of two centers in DB signals is clearly indicated by the shape of the spectra. The Q-band ESR spectra shape reviles that the peak of one center is at g = 2.0055andthe other is around at g = 2.0060. In addition, the DB signal showed dependence on substrate temperature. The dependence of the DB signals can be explained by difference of intensity ratio of the peaks by these two centers. The signal at g = 2.0060 is consistent with the asymmetric ESR signal observed in the microcrystalline silicon embedded in SiO2. W-band ESR measurement indicates that the signal observed at g = 2.0060 is due to single inhomogeneous species and does not consist of plural species.
Aladin: The First European Lidar in Space
Authors: Morançais Didier , Fabre Frédéric
Published: December 2012

After several decades of observations from space, direct measurements of the global threedimensional wind field remain elusive, however crucial to weather predictions. The ALADIN instrument, payload of the AEOLUS satellite (figure 1), will provide measurements of atmospheric wind profiles with global Earth coverage for the climatology and meteorology users. The AEOLUS programme is sponsored by the European Space Agency with a launch planned in 2008.

ALADIN belongs to a new class of Earth Observation payloads and will be the first European Lidar in space. The instrument comprises a diode-pumped high energy Nd:YAG laser and a direct detection receiver operating on aerosol and molecular backscatter signals in parallel. In addition to the Flight Model (FM), two instrument models are developed: a Pre-development Model (PDM) and an Opto-Structure-Thermal Model (OSTM). The OSTM integration has been completed and the flight equipments are under manufacturing. This paper describes the instrument design as well as the development status. The ALADIN instrument is developed under prime contractor EADS Astrium SAS with a consortium of thirty companies.
Conhecimento e percepção dos profissionais a respeito do ruído na unidade neonatal
Authors: Daniele Daniela , Pinheiro Eliana Moreira , Kakehashi Teresa Yoshiko , Balieiro Maria Magda Ferreira Gomes
Published: December 2012

O objetivo deste estudo foi verificar o conhecimento e a percepção de profissionais de Unidade de Terapia Intensiva Neonatal (UTIN) sobre as repercussões do ruído ao neonato, família e profissionais, antes da implementação de um programa educativo. Trata-se de uma pesquisa descritiva, quantitativa, realizada em Unidade de Terapia Intensiva Neonatal de um hospital de São Paulo, com 101 profissionais. Foram utilizados: questionário para a coleta de dados, e os testes de Qui-quadrado e t de Student para a associação entre as variáveis. Os profissionais identificaram a UTIN como muito ruidosa (44,9%), perceberam os efeitos desse ruído durante e após a jornada de trabalho (67,4%) e utilizaram estratégias para amenizá-lo. Embora os profissionais desconheçam a legislação sobre o ruído no ambiente hospitalar, identificaram repercussões para si, recém-nascido e família. Os resultados apontaram para a necessidade de orientar a equipe quanto à legislação, prevenção de ruído e reorganização das práticas assistenciais e estrutura física da Unidade de Terapia Intensiva Neonatal.
Oficinas de espiritualidade: alternativa de cuidado para o tratamento integral de dependentes químicos
Authors: Backes Dirce Stein , Backes Marli Stein , Medeiros Hilda Maria Freitas , Siqueira Daiana Foggiato de , Pereira Simone Barbosa , Dalcin Camila Biazus , Rupolo Irani
Published: December 2012

Trata-se de um relato de experiência vivenciada com usuários de crack sob tratamento de desintoxicação, na qual se buscou alcançar o cuidado integral ao ser humano por meio de oficinas de espiritualidade. Cultivadas e dinamizadas a partir de inspirações dos próprios integrantes, as oficinas se constituem em estratégias capazes de estimular o repensar de atitudes e comportamentos, bem como reassumir a vida com base em novos valores e ideais. O relato visa, em suma, contribuir para a ampliação das discussões sobre o tema, oferecendo subsídios para o repensar da prática do enfermeiro no tratamento de desintoxicação, além de assinalar a necessidade de condução de pesquisas nessa área.
Seroprevalence and risk factors associated with Chlamydophila abortus infection in dairy goats in the Northeast of Brazil
Authors: Santos Carolina S.A.B. , Piatti Rosa M. , Azevedo Sérgio S. , Alves Clebert J. , Higino Severino S.S. , Silva Maria L.C.R. , Brasil Arthur W.L. , Gennari Solange M.
Published: December 2012

Few data are available on the prevalence and risk factors of Chlamydophila abortus infection in goats in Brazil. A cross-sectional study was carried out to determine the flock-level prevalence of C. abortus infection in goats from the semiarid region of the Paraíba State, Northeast region of Brazil, as well as to identify risk factors associated with the infection. Flocks were randomly selected and a pre-established number of female goats > 12 mo old were sampled in each of these flocks. A total of 975 serum samples from 110 flocks were collected, and structured questionnaire focusing on risk factors for C. abortus infection was given to each farmer at the time of blood collection. For the serological diagnosis the complement fixation test (CFT) using C. abortus S26/3 strain as antigen was performed. The flock-level factors for C. abortus prevalence were tested using multivariate logistic regression model. Fifty-five flocks out of 110 presented at least one seropositive animal with an overall prevalence of 50.0% (95%; CI: 40.3%, 59.7%). Ninety-one out of 975 dairy goats examined were seropositive with titers >32, resulting in a frequency of 9.3%. Lend buck for breeding (odds ratio = 2.35; 95% CI: 1.04-5.33) and history of abortions (odds ratio = 3.06; 95% CI: 1.37-6.80) were associated with increased flock prevalence.
Sawfly larval poisoning in cattle: Report on new outbreaks and brief review of the literature
Authors: Tessele Bianca , Brum Juliana Sperotto , Schild Ana Lucia , Soares Mauro P. , Barros Claudio S.L.
Published: December 2012

Sawfly larval poisoning (SLP) is an acute hepatotoxicosis documented in livestock in Australia, Denmark and in countries of South America. It is caused by the ingestion of the larval stage of insects of the suborder Symphyta, order Hymenoptera, commonly known as "sawfly". Three species of sawfly are reportedly involved in the toxicosis. The insect involved in Australian SLP is Lophyrotoma interrupta (Pergidae), in Denmark the cause of SLP is the ingestion of the larvae Arge pullata (Argidae), and in South American countries documented outbreaks of SLP were caused by the ingestion of yet another sawfly, Perreyia flavipes (Pergidae). In all geographical areas where it occurred, SLP causes important livestock losses. In cattle, as well as in other affected species, the disease has a short clinical course and in many outbreaks affected cattle can be found dead. When observed, clinical signs include apathy, recumbence, tremors, paddling movements and death in 24-48 hours. Neurological signs such aggressiveness attributable to hepatic encephalopathy are also observed. In cases with a more protracted course icterus and photodermatitis may develop. Gross findings included ascites, petechiae and ecchymosis over serosal surfaces of thoracic and abdominal cavities, and an enlarged liver that displays accentuation of the lobular pattern and edema of the gall bladder wall. Sawfly larval body fragments and heads are consistently found in the fore stomachs and occasionally abomasum of affected cattle. Main microscopic lesions are restricted to the liver and consist of centrolobular (periacinar) to massive hepatocellular necrosis. In most lobules necrotic areas extended up to the portal triads where only a few viable hepatocytes remain. Mild to moderate lymphocyte necrosis is seen in lymphatic tissues. Cases occur in the winter months when the larval stages of the sawfly are developing. D-amino acid-containing peptides have been found to be the toxic principle in each sawfly involved in SLP. The octapeptide lophyrotomin is the major toxin in the in the larvae of Australian and Danish sawflies and is present in small amounts in the larvae of South American sawfly. The heptadecapeptide pergidin is the main toxin in the South American sawfly while small amounts of pergidin have been found in the other two species of toxic sawfly. During the winter of 2011 (July-August) four outbreaks of SLP were diagnosed in the State of Rio Grande do Sul, Brazil. The findings in those outbreaks are reported here and a brief review of the literature regarding SLP around the world is provided.
Histopathological and immunohistochemical findings of swine with spontaneous influenza A infection in Brazil, 2009-2010
Authors: Watanabe Tatiane T.N. , Almeida Laura L. de , Wouters Flademir , Wouters Angelica T.B. , Zlotowski Priscila , Driemeier David
Published: December 2012

Swine influenza (SI) is caused by the type A swine influenza virus (SIV). It is a highly contagious disease with a rapid course and recovery. The major clinical signs and symptoms are cough, fever, anorexia and poor performance. The disease has been associated with other co-infections in many countries, but not in Brazil, where, however, the first outbreak has been reported in 2011. The main aim of this study was to characterize the histological features in association with the immunohistochemical (IHC) results for influenza A (IA), porcine circovirus type 2 (PCV2) and porcine reproductive and respiratory syndrome virus (PRRSV) in lung samples from 60 pigs submitted to Setor de Patologia Veterinária at the Universidade Federal do Rio Grande do Sul (SPV-UFRGS), Brazil, during 2009-2010. All of these lung samples had changes characterized by interstitial pneumonia with necrotizing bronchiolitis, never observed previously in the evaluation of swine lungs in our laboratory routine. Pigs in this study had showed clinical signs of a respiratory infection. Swine samples originated from Rio Grande do Sul 31 (52%), Santa Catarina 14 (23%), Paraná 11 (18%), and Mato Grosso do Sul 4 (7%). Positive anti-IA IHC labelling was observed in 45% of the cases, which were associated with necrotizing bronchiolitis, atelectasis, purulent bronchopneumonia and hyperemia. Moreover, type II pneumocyte hyperplasia, alveolar and bronchiolar polyp-like structures, bronchus-associated lymphoid tissue (BALT) hyperplasia and pleuritis were the significant features in negative anti-IA IHC, which were also associated with chronic lesions. There were only two cases with positive anti-PCV2 IHC and none to PRRSV. Therefore, SIV was the predominant infectious agent in the lung samples studied. The viral antigen is often absent due to the rapid progress of SI, which may explain the negative IHC results for IA (55%); therefore, IHC should be performed at the beginning of the disease. This study has shown how important a careful histological evaluation is for the diagnosis. Since 2009, a new histological feature of swine pneumonia in animals with respiratory clinical signs has been observed in samples from pigs with clinical respiratory disease submitted to SPV-UFRGS. In addition, the results proved the importance of histological evaluation for swine herd health management.
Leishmanicidal and cholinesterase inhibiting activities of phenolic compounds of Dimorphandra gardneriana and Platymiscium floribundum, native plants from Caatinga biome
Authors: Vila-Nova Nadja S. , Morais Selene M. , Falcão Maria J.C. , Bevilaqua Claudia M.L. , Rondon Fernanda C.M. , Wilson Mary E. , Vieira Icaro G.P. , Andrade Heitor F.
Published: December 2012

In recent years, the Brazilian Health Ministry and the World Health Organization have supported research into new technologies that may contribute to the surveillance, new treatments, and control of visceral leishmaniasis within the country. In light of this, the aim of this study was to isolate compounds from plants of the Caatinga biome, and to investigate their toxicity against promastigote and amastigote forms of Leishmania infantum chagasi, the main responsible parasite for South American visceral leishmaniasis, and evaluate their ability to inhibit acetylcholinesterase enzyme (AChE). A screen assay using luciferase-expressing promastigote form and an in situ ELISA assay were used to measure the viability of promastigote and amastigote forms, respectively, after exposure to these substances. The MTT colorimetric assay was performed to determine the toxicity of these compounds in murine monocytic RAW 264.7 cell line. All compounds were tested in vitro for their anti-cholinesterase properties. A coumarin, scoparone, was isolated from Platymiscium floribundum stems, and the flavonoids rutin and quercetin were isolated from Dimorphandra gardneriana beans. These compounds were purified using silica gel column chromatography, eluted with organic solvents in mixtures of increasing polarity, and identified by spectral analysis. In the leishmanicidal assays, the compounds showed dose-dependent efficacy against the extracellular promastigote forms, with an EC50 for scoporone of 21.4µg/mL, quercetin and rutin 26 and 30.3µg/mL, respectively. The flavonoids presented comparable results to the positive control drug, amphotericin B, against the amastigote forms with EC50 for quercetin and rutin of 10.6 and 43.3µg/mL, respectively. All compounds inhibited AChE with inhibition zones varying from 0.8 to 0.6, indicating a possible mechanism of action for leishmacicidal activity.
Impactos de medidas "antidumping" adotadas pelos EUA sobre o setor siderúrgico de Minas Gerais e o restante do Brasil
Authors: Firme Vinícius de Azevedo Couto , Vasconcelos Claudio R. F.
Published: December 2012

Analisar o impacto de medidas antidumping aplicadas pelos Estados Unidos sobre exportações do setor siderúrgico de Minas Gerais, para o período entre 1999 e 2002, foi o objetivo deste trabalho. Os resultados mostraram que tal medida teve efeitos estatisticamente significativos sobre a redução no fluxo de comércio. Na análise da integração dos resultados econométricos com a abordagem de matrizes inter-regionais de insumo-produto, foi possível concluir que o setor mais afetado, no que se refere à produção, seria a siderurgia mineira, em que o impacto representou mais de 75% do total, no período em análise. Com relação ao emprego, o impacto sobre a siderurgia de Minas Gerais corresponde, em média, a mais de 50% do total de vagas que seriam criadas, caso nenhuma medida antidumping tivesse sido adotada; e a siderurgia do restante do país seria responsável por mais de 16% dos postos de trabalho criados no período.
Mel e açúcar mascavo na cicatrização de feridas
Authors: Santos Ivan Felismino Charas dos , Grosso Sara Luisa Sousa , Bambo Otilia Bata , Nhambirre André Paulo , Cardoso José Manuel Mota , Schmidt Elizabeth Moreira dos Santos , Marujo Renata Bezerra
Published: December 2012

O estudo teve como objetivo comparar a eficácia do mel e do açúcar mascavo na cicatrização de feridas induzidas cirurgicamente na pele de cobaias, para avaliar o tempo de cicatrização, as variações macroscópicas e microscópicas do tecido cicatricial, a contração das feridas e o grau de contaminação. Quinze cobaias da raça Abissínia, machos inteiros, de seis meses de idade e pesando entre 500 a 850 gramas, foram divididas em três grupos com cinco animais cada, nos quais foram induzidas, cirurgicamente, três feridas em cada animal com dimensão de 1,5cm² e distância entre elas de 1,5cm, na região dorsal. A ferida F1 foi tratada diariamente com mel, a ferida F2 com solução salina 0,9% (controle) e a ferida F3 com o açúcar mascavo. A eutanásia foi realizada no Grupo 1 ao sétimo dia após a cirurgia, no Grupo 2 ao décimo quarto dia e no Grupo 3 no vigésimo primeiro dia após a cirurgia, sendo as biópsias encaminhadas para avaliação histopatológica. Foram também realizados swabs das feridas em todos os grupos no terceiro e sétimo dias após a cirurgia e as amostras enviadas para a cultura e isolamento bacteriano. Concluiu-se que as feridas tratadas com o mel cicatrizaram mais rápido em relação às tratadas com o açúcar mascavo, demonstrando a maior propriedade cicatrizante do mel em relação ao açúcar mascavo.
Relacionamento professor-aluno e auto-regulação da aprendizagem no 3º ciclo do ensino médio português
Authors: Azevedo Ângela Sá , Dias Paulo Cesar , Salgado Ana , Guimarães Teresa , Lima Isabel , Barbosa Andreia
Published: December 2012

Este artigo teve como objetivo explorar a relação entre a percepção do comportamento do professor e auto-regulação da aprendizagem na Matemática. As respostas de 625 alunos do 3ºciclo do Ensino Médio Português (7º ao 9º anos) aos questionários QIPBásico e IPAAr permitiram perceber diferenças nas variáveis supracitadas em função do sexo, da idade, do ano de escolaridade e do número de retenções, do nível educacional dos pais, do sexo do professor de Matemática e do número de anos com o mesmo professor. As conclusões mais relevantes para a prática pedagógica prendem-se à relação positiva entre a auto-regulação da aprendizagem dos alunos e a percepção de liderança, apoio e compreensão por parte dos professores, e relação negativa entre a auto-regulação e a percepção de insatisfação, insegurança e repreensão dos seus professores.
Phosphorus behavior on an Oxisol fertilized by phosphate alkaline biosolid and cultivated with common bean
Authors: Silva Luiz C. da , Lucchesi Luiz A. C. , Koehler Henrique S. , Campos Milton C. C.
Published: December 2012

This study aimed to evaluate the extractable phosphorus Mehlich-1 in a distrophic Red-Yellow Latosol (Oxisol) which received alkaline sewage sludge (alkaline biosolid) along with 0, 0.436, 0.872 and 1.745 dag kg-1 of P from three different sources and cultivated with common bean (Phaseolus vulgaris cv. IPR Uirapuru) in greenhouse. It also aimed to quantify the phosphorus uptake by the plant, plant production and the relative agronomic effectiveness index. For the establishment of the treatment the recommended dose was 45.85 kg ha-1 of P from the treatments, except the control (0 dag kg-1 of P). This dose was calculated for 2.5 kg of this Oxisol from Contenda, Paraná State, Brazil, contained in recepients of 3 dm3 with 6 cultivated bean plants (cv. IPR Uirapuru). Phosphorus added in alkaline biosolid increased the extractable phosphorus (Mehlich-1) in soil and phosphorus accumulated in plants as well as the grain and total dry mass production of bean plants. The best level of phosphorus added to alkaline biosolid was 0.436 dag kg-1 of P from the partially acidulated phosphate rock Alvorada and single superphosphate.
Semeadora-adubadora: mecanismos de corte de palha e cargas verticais aplicadas
Authors: Silva Paulo R. A. , Benez Sérgio H. , Jasper Samir P. , Seki André S. , Masiero Fabrício C. , Riquetti Neilor B.
Published: December 2012

Realizou-se este trabalho com o objetivo de avaliar o desempenho dos mecanismos de corte de palha de uma semeadora-adubadora em diferentes coberturas vegetais e cargas verticais aplicadas. O delineamento experimental utilizado foi em blocos ao acaso e esquema fatorial 3 x 4, com 4 repetições. Os trabalhos foram realizados com três diferentes mecanismos de corte de palha (disco liso, disco corrugado e disco ondulado) utilizando-se quatro diferentes cargas verticais (750, 1500, 2250 e 3000 N) em cinco coberturas de palha (milho, sorgo, aveia preta, triticale e nabiça). Os resultados mostraram que quanto maior a quantidade de matéria seca da cobertura vegetal maior também é a demanda de forças horizontal e vertical. O disco de corte ondulado possibilita os maiores valores de área de solo mobilizado, exige maiores valores de força horizontal, força vertical e força horizontal por profundidade de corte dos discos (força específica). O tratamento com disco liso exigiu maiores valores de força horizontal por área de solo mobilizado e de força vertical nas coberturas de milho e sorgo.
Avaliação da atividade fitotóxica com enfoque alelopático do extrato das cascas de Celtis iguanaea (Jacq.) Sargent Ulmaceae e purificação de dois triterpenos
Authors: Trevisan R.R. , Lima C.P. , Miyazaki C.M.S. , Pesci F.A. , Silva C.B. , Hirota B.C.K. , Lordello A.L.L. , Miguel O.G. , Miguel M.D. , Zanin S.M.W.
Published: December 2012

A espécie Celtis iguanaea (Jacq.) Sargent é popularmente conhecida como esporão de galo ou grão de galo. As folhas são indicadas pelo uso popular para o tratamento de dores no corpo e no peito, para reumatismo, asma, cólicas, má digestão e como diurético; as raízes são utilizadas para infecções urinárias e as cascas para a febre. O presente trabalho objetivou contribuir para o estudo fitoquímico e atividade fitotóxica com enfoque alelopático das cascas de Celtis iguanaea. O extrato etanólico foi submetido à partição com os solventes hexano, clorofórmio e acetato de etila. As substâncias friedelina e epifriedelinol (triterpenos) foram isoladas da fração hexano e identificadas por meio de métodos espectroscópicos de RMN de ¹H e 13C. O extrato bruto na concentração de 0,1 mg mL-1 causou inibição acentuada do hipocótilo em 34,97% e estimulou o crescimento da radícula em 29,64% de plântulas de Lactuca sativa. No ensaio de toxicidade frente à Artemia salina o extrato bruto e frações apresentaram uma CL50 superior a 1000 μg mL-1, indicando que o mesmo não possui efeito tóxico.
Estaquia caulinar de guaçatonga (Casearia sylvestris Swartz) nas quatro estações do ano, com aplicação de diferentes concentrações de AIB
Authors: Spandre P. , Zanette F. , Biasi L.A. , Koheler H.S. , Niesing P.C.
Published: December 2012

Casearia sylvestris Swartz (Salicaceae) ou guaçatonga é uma árvore nativa do México, da América Central, e da América do Sul, com grande importância ecológica, farmacológica, e comercial. No entanto, como a maioria das espécies nativas de interesse medicinal no Brasil, a guaçatonga não é cultivada comercialmente, sendo obtida por extrativismo. O presente trabalho foi conduzido com o objetivo de testar um protocolo de propagação vegetativa de guaçatonga por meio da estaquia, visando identificar qual a melhor estação do ano para o enraizamento de estacas e avaliar o efeito da utilização do regulador vegetal ácido indolbutírico (AIB). No outono, inverno e primavera de 2007, e no verão de 2008, estacas caulinares semilenhosas de 12-14 cm de comprimento e com duas folhas foram preparadas e tratadas com AIB (0, 1000, 2000 e 3000 mg L-1), em solução alcoólica, através da imersão rápida por 10 segundos da base das estacas, e foram plantadas em tubetes contendo substrato Plantmax HT® em casa-de-vegetação sob nebulização intermitente. O delineamento experimental utilizado foi o inteiramente casualizado, com 4 repetições, 4 tratamentos, e 16 estacas por parcela. Todos os experimentos foram avaliados após 90 dias, sendo que para dois deles (primavera 2007 e verão 2008) prolongou-se o tempo de permanência em casa-de-vegetação para melhor desenvolvimento das raízes. Foram avaliados os parâmetros: porcentagem de estacas enraizadas, porcentagem de estacas vivas (com calos e sem raízes, sem calos e sem raízes), porcentagem de folhas retidas, porcentagem de estacas mortas, número de raízes, comprimento das três maiores raízes (cm), e média da massa seca das raízes (mg). Não ocorreu enraizamento nas estacas retiradas no outono e no inverno. Com as estacas retiradas na primavera obteve-se 39,1% de enraizamento. Estacas coletadas no verão não responderam como o esperado, apresentando, após 240 dias, 6,3% de enraizamento no tratamento com 3000 mg L-1 de AIB. O AIB até 3000 mg L-1 não estimulou o enraizamento de estacas de guaçatonga e a melhor estação do ano para a estaquia é a primavera.
Uma visualização do princípio de Huygens-Fresnel na obtenção de um padrão de difração
Authors: Barbosa Valmar Carneiro , Breitschaft Ana Maria Senra , Mendonça José Paulo Rodrigues Furtado de , Moreira Leonardo Marmo , Moraes Pedro Claudio Guaranho de
Published: December 2012

Utilizando a relação que fornece a irradiância devida à interferência de fontes pontuais, mostramos por meio de gráficos como o princípio de Huygens-Fresnel funciona quando é aplicado para determinar o padrão de difração de Fraunhofer gerado por uma onda plana que incide perpendicularmente em um anteparo que contém apenas uma fenda. Desta forma, somos capazes de identificar como se originam os picos principal e secundários de difração, o que não é entendido claramente a partir da obtenção analítica do padrão de difração em questão.
Rolamento sem deslizamento: um exemplo ilustrativo capaz de mostrar muitos conflitos conceituais
Authors: Nelson Osman Rosso
Published: December 2012

O presente trabalho é mais um esforço no processo de identificação de erros conceituais referentes a conteúdos de mecânica clássica, identificados em alunos no nível universitário.
II cycle compressibility from satellite measurements
Authors: FERRONATO M. , CASTELLETTO N. , GAMBOLATI G. , JANNA C. , TEATINI P.
Published: December 2012

Knowledge of ground compressibility in unloading/reloading conditions is of paramount importance in several geomechanical processes, but its estimate is often affected by large uncertainties, especially for deep rocks. Satellite measurements of the land motion can help improve this information. The present study investigates the ground response due to underground gas storage activities as revealed by satellite interferometric measurements in three gas fields of the Po river basin, Italy. The ground proves to behave elastically, moving upwards and downwards in response to gas injection and extraction, respectively. The accurate calibration of a detailed geomechanical, transversely isotropic, finite-element model allows for an indirect estimate of the vertical ground compressibility in unloading/reloading conditions, which proves consistent with the results already available from the same basin. Assuming a hypo-plastic constitutive model for the compressibility in virgin loading conditions, the ratio between I cycle and II cycle compressibility at the load inversion turns out to be between 3·5 and 4·0 in the depth range 1100–1500 m, again proving to be in good agreement with other results obtained in the same basin.
The influence of geomorphic processes on plant distribution and abundance as reflected in plant tolerance curves
Authors: Chase M. N. , Johnson E. A. , Martin Y. E.
Published: December 2012

Ecologists describe plant distribution using direct gradient analysis, by which a tolerance curve of species abundance is described along an environmental gradient (any environmental variable that affects plant distribution). Soil moisture is generally the gradient in low‐relief areas that explains the most variation. Traditional direct gradient analyses have used terrain structure (i.e., transects up or down hillslopes) as a correlate to soil moisture. Here we use a numerical tectonic and geomorphic process‐based landscape development model to create two landscapes with different geomorphic characteristics: (1) to demonstrate the influence of geomorphic processes on soil moisture patterns and plant distribution and (2) to evaluate the effectiveness of transects in describing moisture gradients and tolerance curves on landscapes dominated by creep or overland flow. We use a topographic index to approximate the distribution of soil moisture as it is determined by the shape of these different landscapes. Transects are placed on hillslopes in each model landscape and used to construct tolerance curves.

Results show that transect methods that use the distance from the channel to the ridgeline as an approximation of soil moisture create variable tolerance curves for the same plant both within a single landscape and between different landscapes. The reason for these differences is that transects do not take into account the three‐dimensional landscape form that explains water movement. Landscapes have regions of convexity and flow path divergence and regions of concavity and flow path convergence that, along with hillslope length, determine contributing area. In addition, hillslope curvature results in varying capacities to retain water. However, when the topographic index is used instead of hillslope transect position, tolerance curves from the same and different landscapes reflect the differences the topographic structure has on soil moisture. We thus show that traditional methods of direct gradient analysis are not always adequate as they do not tend to consider that soil moisture depends on hillslope length, curvature, and slope. Furthermore, we show that within and between landscapes there are differences in spatial distributions of soil moisture that are reflections of the geomorphic processes that created them.
Influence of natural and novel organic carbon sources on denitrification in forest, degraded urban, and restored streams
Authors: Newcomer Tamara A. , Kaushal Sujay S. , Mayer Paul M. , Shields Amy R. , Canuel Elizabeth A. , Groffman Peter M. , Gold Arthur J.
Published: December 2012

Organic carbon is important in regulating ecosystem function, and its source and abundance may be altered by urbanization. We investigated shifts in organic carbon quantity and quality associated with urbanization and ecosystem restoration, and its potential effects on denitrification at the riparian–stream interface. Field measurements of streamwater chemistry, organic carbon characterization, and laboratory‐based denitrification experiments were completed at two forested, two restored, and two unrestored urban streams at the Baltimore Long‐Term Ecological Research site, Maryland, USA. Dissolved organic carbon (DOC) and nitrate loads increased with runoff according to a power‐law function that varied across sites. Stable isotopes and molar C:N ratios suggested that stream particulate organic matter (POM) was a mixture of periphyton, leaves, and grass that varied across site types. Stable‐isotope signatures and lipid biomarker analyses of sediments showed that terrestrial organic carbon sources in streams varied as a result of riparian vegetation. Laboratory experiments indicated that organic carbon amendments significantly increased rates of denitrification (35.1 ± 9.4 ng N·[g dry sediment]−1·h−1; mean ± SE) more than nitrate amendments (10.4 ± 4.0 ng N·[g dry sediment]−1·h−1) across streamflow conditions and sites. Denitrification experiments with naturally occurring carbon sources showed that denitrification was significantly higher with grass clippings from home lawns (1244 ± 331 ng N·g dry sediment−1·h−1), and overall unrestored urban sites showed significantly higher denitrification rates than restored and forest sites. We found that urbanization influences organic carbon sources and quality in streams, which can have substantial downstream impacts on ecosystem services such as denitrification.
Introduction of Nippleless Tubing Stop Plug Application in Pakistan
Authors: Sherwani Waseem Akhtar , Qureshi Imran , Khattak Kifayatullah , Ali Abdul Salam , Ali Syed Dost
Published: December 2012

Well control is the management of the hazardous effects caused by the unexpected well release. In a production well, downhole safety valve and X-mass tree are considered the main barriers against the well release in the event of a worst case scenario surface disaster. Inadequate risk management and improperly managed well control situations cause blowouts, potentially resulting in a fire hazard.

This paper describes a case history of a production well where a tubing string was roded severely during production phase. The problem was detected while attempting to retrieve the separation sleeve in the long string which was not accessible at the required depth. Downhole camera indicated that 90% of the long string had been eroded and remaining 10% is connected with the flow coupling. Thus, full workover job was required to replace tubing strings. However, the lack of well control barrier in the tubing to prevent uncontrolled flow of hydrocarbons prior to blowout preventer (BOP) installation for the workover was a serious safety concern.

Introduction of Nippleless Tubing-Stop Plug technology provide an effective, safe and economical remedial solution to the problem.
First Application of Extended Range Electromagnetic MWD Technology in Pakistan for a Horizontal Well Drilled Underbalanced-Case Study and Lesson Learned
Authors: Saleem Saad , Sattar Muhammad Suhail , Shahzad Atif , Ziadat Wael , Sabir Shahid Majeed
Published: December 2012

The name "Sui" has become synonymous with natural gas in Pakistan. Sui is Pakistan Petroleum Limited's (PPL) flagship gas field. Commercial exploitation of this field began in 1955.

Two major reservoirs of this field are Sui Main Limestone (SML) and Sui Upper Limestone (SUL). Both the reservoirs have become highly depleted by time. Conventional drilling technologies in these formations result in complete loss of drilling fluid, stuck pipe and severe formation damage issues.

Pakistan Petroleum Limited (PPL) planned to drill a horizontal well Sui-93(M), where target reservoir was Sui Main Limestone (SML). Drilling a horizontal well with conventional drilling techniques can cause a complete loss of drilling fluid. Underbalanced Drilling integrated with electromagnetic telemetry transmission was successfully used to drill this well to a target depth of 2200m MD with complete directional controls. Electromagnetic transmission modeling was performed on the resistivity data of offset wells to determine signal attenuation for Sui-93(M) Well. Based on modeling results it was decided to run an extended range set-up with a downhole antenna.

The main reason for using EM-MWD was to provide real time data for annular pressure (APWD sensor) and directional controls in UBD environment. The APWD (annular pressure while drilling-real time ECD) sensor was considered mandatory to monitor and ensure underbalanced condition while drilling, thereby avoiding significant problems such as lost circulation and stuck pipe.

This paper discusses the planning, results, problems and lessons learned during the first application of the Extended Range EM-MWD (Electromagnetic-Measurement while drilling) technology in Sui-93(M) well.

The application of EM-MWD along with UB technology represents a stepwise progression for improving PPL's ability to exploit mature reservoirs, especially those that are severely depleted like in Sui Gas Field, Pakistan.