Desenvolvimento da técnica de RT-PCR em tempo real para detecção e diferenciação de estirpes do vírus da bronquite infecciosa das galinhas

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Política cambial brasileira e seus efeitos nas exportações paraenses: 1990 - 2003

O principal objetivo da dissertação é analisar os efeitos que a política cambial brasileira promoveu nas exportações F.O.B. de bauxita, alumínio primário, minério de ferro e caulim. Para tal, é desenvolvido um modelo econométrico, Modelo de ajustamento parcial de Nerlove, procurando avaliar os padrões de reação das exportações no curto e longo prazos. Os dados utilizados são trimestrais e cobrem o período de 1990 a 2003. As regressões foram estimadas através do método dos Mínimos Quadrados Ordinários (MQO). As variáveis elegidas como explicativas foram a taxa de câmbio real efetiva brasileira, a renda mundial, a capacidade produtiva da indústria brasileira, o produto interno bruto da indústria brasileira e uma variável dummy (que capta a influência da lei Kandir). Os resultados das regressões mostram que: as exportações são relativamente sensíveis ao crescimento da economia brasileira e mundial; e, a taxa de câmbio real efetiva brasileira (proxy da política cambial) produziu efeitos importantes na evolução das exportações do setor mínero-metalúrgico paraense.

Peginterferon plus ribavirin and sustained virological response rate in HCV-related advanced fibrosis: a real life study

Background: Tolerance and response to antiviral HCV treatment is poor in advanced fibrosis. The aim of this study was to assess SVR rate and its predictive factors in HCV advanced fibrosis patients treated in real life with full dose PEG-IFN plus RBV and to evaluate the adverse events related to treatment. Methods: A multicentric, retrospective study was conducted at six university hospitals. METAVIR F3 and F4 HCV monoinfected patients who were treated with PEG-IFN and RBV had their data analyzed. A stepwise logistic regression analysis was performed to identify the variables independently related to SVR. Adverse events were recorded during treatment. Results: 308 patients were included, 75% genotype 1 and 23% genotype 3. METAVIR F3 was present in 39% and F4 in 61% of patients. The median Child Pugh score for F4 patients was 5 (5–9). The global SVR rate was 34%, 11% were relapsers and 55% were nonresponders. SVR rates were similar between patients treated with PEG-IFN alfa 2a or alfa 2b (p = 0.24). SVR rates according to Child–Pugh score were 26% (Child A) and 18% (Child B). The independent factors related to SVR in F4 patients were genotype 3, RVR and fewer Child Pugh score points. Treatment interruption occurred in 31% patients and death occurred in 1.9%, all with liver cirrhosis. Conclusion: Treatment of HCV in patients with advanced fibrosis should not be postponed. However, a very careful evaluation of cirrhotic patients must be performed before treatment is indicated and careful monitoring is required during treatment.

Effect of hexadecyltrimethylammonium bromide-based microemulsions on the rate of decomposition of the beta-lactam antibiotic cephaclor

Microemulsions of hexadecyltrimethylammonium bromide (HTAB)/n-butanol/hexadecane/water catalyze the intramolecular degradation of cephaclor. The rate increase is a sensitive function of the microemulsion volume fraction and salt concentration. The effects of microemulsions, analyzed quantitatively using a pseudophase ion-exchange model, assumed that the extent of ion dissociation from the microemulsions varies with volume fraction. Comparison of micellar and microemulsion effects on the same reaction shows that microemulsions are less effective catalysts. Acceleration decreased significantly by increasing the relative proportion of n-butanol ratio in microemulsions and by addition of n-butanol in HTAB micelles. Comparison of the activation parameters of the reaction in aqueous solution, microemulsions, and micelles suggests that catalysis by both aggregates is driven mainly by entropic contributions.

Formation and surface exchange of nitrous acid

Die salpetrige Säure (HONO) ist eine der reaktiven Stickstoffkomponenten der Atmosphäre und Pedosphäre. Die genauen Bildungswege von HONO, sowie der gegenseitige Austausch von HONO zwischen Atmosphäre und Pedosphäre sind noch nicht vollständig aufgedeckt. Bei der HONO-Photolyse entsteht das Hydroxylradikal (OH) und Stickstoffmonooxid (NO), was die Bedeutsamkeit von HONO für die atmosphärische Photochemie widerspiegelt.rnUm die genannte Bildung von HONO im Boden und dessen anschließenden Austausch mit der Atmosphäre zu untersuchen, wurden Messungen von Bodenproben mit dynamischen Kammern durchgeführt. Im Labor gemessene Emissionsflüsse von Wasser, NO und HONO zeigen, dass die Emission von HONO in vergleichbarem Umfang und im gleichen Bodenfeuchtebereich wie die für NO (von 6.5 bis 56.0 % WHC) stattfindet. Die Höhe der HONO-Emissionsflüsse bei neutralen bis basischen pH-Werten und die Aktivierungsenergie der HONO-Emissionsflüsse führen zu der Annahme, dass die mikrobielle Nitrifikation die Hauptquelle für die HONO-Emission darstellt. Inhibierungsexperimente mit einer Bodenprobe und die Messung einer Reinkultur von Nitrosomonas europaea bestärkten diese Theorie. Als Schlussfolgerung wurde das konzeptionelle Model der Bodenemission verschiedener Stickstoffkomponenten in Abhängigkeit von dem Wasserhaushalt des Bodens für HONO erweitert.rnIn einem weiteren Versuch wurde zum Spülen der dynamischen Kammer Luft mit erhöhtem Mischungsverhältnis von HONO verwendet. Die Messung einer hervorragend charakterisierten Bodenprobe zeigte bidirektionale Flüsse von HONO. Somit können Böden nicht nur als HONO-Quelle, sondern auch je nach Bedingungen als effektive Senke dienen. rnAußerdem konnte gezeigt werden, dass das Verhältnis von HONO- zu NO-Emissionen mit dem pH-Wert des Bodens korreliert. Grund könnte die erhöhte Reaktivität von HONO bei niedrigem pH-Wert und die längere Aufenthaltsdauer von HONO verursacht durch reduzierte Gasdiffusion im Bodenporenraum sein, da ein niedriger pH-Wert mit erhöhter Bodenfeuchte am Maximum der Emission einhergeht. Es konnte gezeigt werden, dass die effektive Diffusion von Gasen im Bodenporenraum und die effektive Diffusion von Ionen in der Bodenlösung die HONO-Produktion und den Austausch von HONO mit der Atmosphäre begrenzen. rnErgänzend zu den Messungen im Labor wurde HONO während der Messkampagne HUMPPA-COPEC 2010 im borealen Nadelwald simultan in der Höhe von 1 m über dem Boden und 2 bis 3 m über dem Blätterdach gemessen. Die Budgetberechnungen für HONO zeigen, dass für HONO sämtliche bekannte Quellen und Senken in Bezug auf die übermächtige HONO-Photolyserate tagsüber vernachlässigbar sind (< 20%). Weder Bodenemissionen von HONO, noch die Photolyse von an Oberflächen adsorbierter Salpetersäure können die fehlende Quelle erklären. Die lichtinduzierte Reduktion von Stickstoffdioxid (NO2) an Oberflächen konnte nicht ausgeschlossen werden. Es zeigte sich jedoch, dass die fehlende Quelle stärker mit der HONO-Photolyserate korreliert als mit der entsprechenden Photolysefrequenz, die proportional zur Photolysefrequenz von NO2 ist. Somit lässt sich schlussfolgern, dass entweder die Photolyserate von HONO überschätzt wird oder dass immer noch eine unbekannte, HONO-Quelle existiert, die mit der Photolyserate sehr stark korreliert. rn rn

Real-life results of balloon kyphoplasty for vertebral compression fractures from the SWISSspine registry

BACKGROUND CONTEXT The Swiss Federal Office of Public Health mandated a nationwide health technology assessment-registry for balloon kyphoplasty (BKP) for decision making on reimbursement of these interventions. The early results of the registry led to a permanent coverage of BKP by basic health insurance. The documentation was continued for further evidence generation. PURPOSE This analysis reports on the 1 year results of patients after BKP treatment. STUDY DESIGN Prospective multicenter observational case series. PATIENT SAMPLE The data on 625 cases with 819 treated vertebrae were documented from March 2005 to May 2012. OUTCOME MEASURES Surgeon-administered outcome instruments were primary intervention form for BKP and the follow-up form; patient self-reported measures were EuroQol-5D questionnaire, North American Spine Society outcome instrument /Core Outcome Measures Index (including visual analog scale), and a comorbidity questionnaire. Outcome measures were back pain, medication, quality of life (QoL), cement extrusions, and new fractures within the first postoperative year. METHODS Data were recorded preoperatively and at 3 to 6-month and 1-year follow-ups. Wilcoxon signed-rank test was used for comparison of pre- with postoperative measurements. Multivariate logistic regression was used to identify factors with a significant influence on the outcome. RESULTS Seventy percent of patients were women with mean age of 71 years (range, 18-91 years); mean age of men was 65 years (range, 15-93 years). Significant and clinically relevant reduction of back pain, improvement of QoL, and reduction of pain killer consumption was seen within the first postoperative year. Preoperative back pain decreased from 69.3 to 29.0 at 3 to 6-month and remained unchanged at 1-year follow-ups. Consequently, QoL improved from 0.23 to 0.71 and 0.75 at the same follow-up intervals. The overall vertebra-based cement extrusion rates with and without extrusions into intervertebral discs were 22.1% and 15.3%, respectively. Symptomatic cement extrusions with radiculopathy were five (0.8%). A new vertebral fracture within a year from the BKP surgery was observed in 18.4% of the patients. CONCLUSIONS The results of the largest observational study for BKP so far are consistent with published randomized trials and systematic reviews. In this routine health care setting, BKP is safe and effective in reducing pain, improving QoL, and lowering pain_killer consumption and has an acceptable rate of cement extrusions. Postoperative outcome results show clear and significant clinical improvement at early follow-up that remain stable during the first postoperative year.

From quantum to classical dynamics: The relativistic O ( N ) model in the framework of the real-time functional renormalization group

We investigate the transition from unitary to dissipative dynamics in the relativistic O(N) vector model with the λ(φ2)2 interaction using the nonperturbative functional renormalization group in the real-time formalism. In thermal equilibrium, the theory is characterized by two scales, the interaction range for coherent scattering of particles and the mean free path determined by the rate of incoherent collisions with excitations in the thermal medium. Their competition determines the renormalization group flow and the effective dynamics of the model. Here we quantify the dynamic properties of the model in terms of the scale-dependent dynamic critical exponent z in the limit of large temperatures and in 2≤d≤4 spatial dimensions. We contrast our results to the behavior expected at vanishing temperature and address the question of the appropriate dynamic universality class for the given microscopic theory.

Non-Parametric Tests of Real Exchange rates in the Post-Bretton Woods Era

This paper examines the mean-reverting property of real exchange rates. Earlier studies have generally not been able to reject the null hypothesis of a unit-root in real exchange rates, especially for the post-Bretton Woods floating period. The results imply that long-run purchasing power parity does not hold. More recent studies, especially those using panel unit-root tests, have found more favorable results, however. But, Karlsson and Löthgren (2000) and others have recently pointed out several potential pitfalls of panel unit-root tests. Thus, the panel unit-root test results are suggestive, but they are far from conclusive. Moreover, consistent individual country time series evidence that supports long-run purchasing power parity continues to be scarce. In this paper, we test for long memory using Lo's (1991) modified rescaled range test, and the rescaled variance test of Giraitis, Kokoszka, Leipus, and Teyssière (2003). Our testing procedure provides a non-parametric alternative to the parametric tests commonly used in this literature. Our data set consists of monthly observations from April 1973 to April 2001 of the G-7 countries in the OECD. Our two tests find conflicting results when we use U.S. dollar real exchange rates. However, when non-U.S. dollar real exchange rates are used, we find only two cases out of fifteen where the null hypothesis of an unit-root with short-term dependence can be rejected in favor of the alternative hypothesis of long-term dependence using the modified rescaled range test, and only one case when using the rescaled variance test. Our results therefore provide a contrast to the recent favorable panel unit-root test results.

Storage requirements for PV power ramp-rate control

Short-term variability in the power generated by large grid-connected photovoltaic (PV) plants can negatively affect power quality and the network reliability. New grid-codes require combining the PV generator with some form of energy storage technology in order to reduce short-term PV power fluctuation. This paper proposes an effective method in order to calculate, for any PV plant size and maximum allowable ramp-rate, the maximum power and the minimum energy storage requirements alike. The general validity of this method is corroborated with extensive simulation exercises performed with real 5-s one year data of 500 kW inverters at the 38.5 MW Amaraleja (Portugal) PV plant and two other PV plants located in Navarra (Spain), at a distance of more than 660 km from Amaraleja.

Purification and characterization of a guanine nucleotide-exchange protein for ADP-ribosylation factor from spleen cytosol.

ADP-ribosylation factors (ARFs) are 20-kDa guanine nucleotide-binding proteins and are active in the GTP-bound state and inactive with GDP bound. ARF-GTP has a critical role in vesicular transport in several cellular compartments. Conversion of ARF-GDP to ARF-GTP is promoted by a guanine nucleotide-exchange protein (GEP). We earlier reported the isolation from bovine brain cytosol of a 700-kDa protein complex containing GEP activity that was inhibited by brefeldin A (BFA). Partial purification yielded an approximately 60-kDa BFA-insensitive GEP that enhanced binding of ARF1 and ARF3 to Golgi membranes. GEP has now been purified extensively from rat spleen cytosol in a BFA-insensitive, approximately 55-kDa form. It activated class I ARFs (ARFs 1 and 3) that were N-terminally myristoylated, but not nonmyristoylated ARFs from class-I, II, or III. GEP activity required MgCl2. In the presence of 0.6-0.8 mM MgCl2 and 1 mM EDTA, binding of guanosine 5'-[gamma[35S]thio]triphosphate ([35S]GTP gamma S) by ARF1 and ARF3 was equally high without and with GEP. At higher Mg2+ concentrations, binding without GEP was much lower; with 2-5 mM MgCl2, GEP-stimulated binding was maximal. The rate of GDP binding was much less than that of GTP gamma S with and without GEP. Phospholipids were necessary for GEP activity; phosphatidylinositol was more effective than phosphatidylserine, and phosphatidic acid was less so. Other phospholipids tested were ineffective. Maximal effects required approximately 200 microM phospholipid, with half-maximal activation at 15-20 microM. Release of bound [35S]GTP gamma S from ARF3 required the presence of both GEP and unlabeled GTP or GTP gamma S; GDP was much less effective. This characterization of the striking effects of Mg2+ concentration and specific phospholipids on the purified BFA-insensitive ARF GEP should facilitate experiments to define its function in vesicular transport.

Real-time detection of DNA hybridization and melting on oligonucleotide arrays by using optical wave guides.

The challenge of the Human Genome Project is to increase the rate of DNA sequence acquisition by two orders of magnitude to complete sequencing of the human genome by the year 2000. The present work describes a rapid detection method using a two-dimensional optical wave guide that allows measurement of real-time binding or melting of a light-scattering label on a DNA array. A particulate label on the target DNA acts as a light-scattering source when illuminated by the evanescent wave of the wave guide and only the label bound to the surface generates a signal. Imaging/visual examination of the scattered light permits interrogation of the entire array simultaneously. Hybridization specificity is equivalent to that obtained with a conventional system using autoradiography. Wave guide melting curves are consistent with those obtained in the liquid phase and single-base discrimination is facile. Dilution experiments showed an apparent lower limit of detection at 0.4 nM oligonucleotide. This performance is comparable to the best currently known fluorescence-based systems. In addition, wave guide detection allows manipulation of hybridization stringency during detection and thereby reduces DNA chip complexity. It is anticipated that this methodology will provide a powerful tool for diagnostic applications that require rapid cost-effective detection of variations from known sequences.

Análise do impacto das políticas de intervenção no setor do agronegócio sobre a cadeia de carne bovina na Venezuela

O objetivo deste trabalho foi analisar o desempenho da cadeia de carne bovina na Venezuela sob o efeito de políticas de intervenção estatal principalmente nas últimas décadas. Para tanto, foi empregada a abordagem teórica do enfoque sistêmico em conjunto com metodologia que se apoiou em um modelo econométrico para explicar o efeito de variáveis tecnológicas e macroeconômicas no agronegócio vis a vis a resultante da produção doméstica de carne bovina nas últimas décadas. Os resultados mostram que, no marco de mudanças institucionais estabelecidas desde a década de 1980 e especialmente as intervenções governamentais vigentes a partir do ano de 2003, a cadeia de carne bovina da Venezuela apresenta um desempenho negocial preocupante e não sustentável. Na última década, a Venezuela decresceu seu inventário bovino a uma taxa média anual de 2,56% entre 2003 e 2014. O número de cabeças/habitante diminuiu a uma taxa anual de 1,30% entre 1960 e 2014, ficando em 0,38 cabeças/habitante. O número de cabeças abatidas sobre o total do rebanho (taxa de desfrute geral do rebanho) foi de 10,82% para o ano de 2014, inferior à média de países vizinhos como Colômbia e Brasil que ficaram em 20,85% e 19,42% respectivamente. A produção doméstica de carne bovina decresceu a uma taxa anual de 2,22% entre 1997 e 2014 (mesmo considerando o abate de bovinos importados). A quantidade de carne oriunda de animais importados cresceu até alcançar um máximo de 58,51% do abate nacional, em 2013. Isto significou um decréscimo real da produção endógena de 71,55% entre os anos de 1997 e 2013. Neste contexto, a produção nacional percapita diminuiu de 18,31 kg/habitante (em 1997) para um mínimo de 3,97 kg/habitante (em 2013). Para o atendimento da demanda doméstica passou-se a contar, crescentemente, com importações de carne in natura que cresceram em volume inicial de 0,59 mil toneladas (t) de equivalente carcaça (em 1997) para um máximo de 307,57 mil t em 2008. A taxa de penetração das importações de carne bovina equivalente (carne e bovinos em pé) resultou em 79,54% do atendimento da demanda doméstica em 2013 (cerca de 15,45 kg/habitante/ano). Neste contexto, as intervenções mais relevantes têm sido a Lei de Terras que propiciou um ambiente de insegurança jurídica; os controles de preços e a política cambial que criaram distorções no mercado; e, a crescente influência nas redes de distribuição de alimentos, com forte dependência do comércio exterior, alavancado com os incrementos no preço internacional do petróleo entre 2003 e 2014. Tudo isto tem resultado em um cenário de desmonte da produção interna da carne bovina, que pode ser visualizado em episódios crescentes de escassez deste produto no mercado interno. Ao final, são sugeridas algumas práticas de políticas pública e setoriais para a reversão desse quadro insustentável para esta importante cadeia de negócios da Venezuela.

Effective leadership in salient groups: Revisiting leader-member exchange theory from the perspective of the social identity theory of leadership

Two studies compared leader-member exchange (LMX) theory and the social identity theory of leadership. Study 1 surveyed 439 employees of organizations in Wales, measuring Work group salience, leader-member relations, and perceived leadership effectiveness. Study 2 surveyed 128 members of organizations in India, measuring identification not salience and also individualism/collectivism. Both studies provided good support for social identity predictions. Depersonalized leader-member relations were associated with greater leadership effectiveness among high- than low-salient groups (Study 1) and among high than low identifiers (Study 2). Personalized leadership effectiveness was less affected by salience (Study 1) and unaffected by identification (Study 2). Low-salience groups preferred personalized leadership more than did high-salience groups (Study 1). Low identifiers showed no preference but high identifiers preferred depersonalized leadership (Study 2). In Study 2, collectivists did not Prefer depersonalized as opposed to personalized leadership, whereas individualists did, probably because collectivists focus more on the relational self.