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Transmission and switching in digital telecommunication networks require distribution of precise time signals among the nodes. Commercial systems usually adopt a master-slave (MS) clock distribution strategy building slave nodes with phase-locked loop (PLL) circuits. PLLs are responsible for synchronizing their local oscillations with signals from master nodes, providing reliable clocks in all nodes. The dynamics of a PLL is described by an ordinary nonlinear differential equation, with order one plus the order of its internal linear low-pass filter. Second-order loops are commonly used because their synchronous state is asymptotically stable and the lock-in range and design parameters are expressed by a linear equivalent system [Gardner FM. Phaselock techniques. New York: John Wiley & Sons: 1979]. In spite of being simple and robust, second-order PLLs frequently present double-frequency terms in PD output and it is very difficult to adapt a first-order filter in order to cut off these components [Piqueira JRC, Monteiro LHA. Considering second-harmonic terms in the operation of the phase detector for second order phase-locked loop. IEEE Trans Circuits Syst [2003;50(6):805-9; Piqueira JRC, Monteiro LHA. All-pole phase-locked loops: calculating lock-in range by using Evan`s root-locus. Int J Control 2006;79(7):822-9]. Consequently, higher-order filters are used, resulting in nonlinear loops with order greater than 2. Such systems, due to high order and nonlinear terms, depending on parameters combinations, can present some undesirable behaviors, resulting from bifurcations, as error oscillation and chaos, decreasing synchronization ranges. In this work, we consider a second-order Sallen-Key loop filter [van Valkenburg ME. Analog filter design. New York: Holt, Rinehart & Winston; 1982] implying a third order PLL The resulting lock-in range of the third-order PLL is determined by two bifurcation conditions: a saddle-node and a Hopf. (C) 2008 Elsevier B.V. All rights reserved.

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Vecuronium bromide is a neuromuscular blocking agent used for anesthesia to induce skeletal muscle relaxation. HPLC and CZE analytical methods were developed and validated for the quantitative determination of vecuronium bromide. The HPLC method was achieved on an amino column (Luna 150 x 4.6 mm, 5 mu m) using UV detection at 205 nm. The mobile phase was composed of acetonitrile:water containing 25.0 mmol L(-1) of sodium phosphate monobasic (50:50 v/v), pH 4.6 and flow rate of 1.0 mL min(-1). The CZE method was achieved on an uncoated fused-silica capillary (40.0 cm total length, 31.5 cm effective length and 50 mu m i.d.) using indirect UV detection at 230 nm. The electrolyte comprised 1.0 mmol L(-1) of quinine sulfate dihydrate at pH 3.3 and 8.0% of acetonitrile. The results were used to compare both techniques. No significant differences were observed (p > 0.05).

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In breast cancer patients, primary chemotherapy is associated with the same survival benefits as adjuvant chemotherapy. Residual tumors represent a clinical challenge, Lis they may be resistant to additional cycles of the same drugs. Our aim was to identify differential transcripts expressed in residual tumors, after neoadjuvant chemotherapy, that might be related with tumor resistance. Hence, 16 patients with paired tumor samples, collected before and after treatment (4 cycles doxorubicin/cyclophosphamide, AC) had their gene expression evaluated on cDNA microarray slides containing 4,608 genes. Three hundred and eighty-nine genes were differentially expressed (paired Student`s t-test, pFDR<0.01) between pre- and post-chemotherapy samples and among the regulated functions were the JNK cascade and cell death. Unsupervised hierarchical clustering identified one branch comprising exclusively, eight pre-chemotherapy samples and another branch, including the former correspondent eight post-chemotherapy samples and other 16 paired pre/post-chemotherapy samples. No differences in clinical and tumor parameters could explain this clustering. Another group of I I patients with paired samples had expression of selected genes determined by real-time RT-PCR and CTGF and DUSP1 were confirmed more expressed in post- as compared to pre-chemotherapy samples. After neoadjuvant chemotherapy some residual samples may retain their molecular signature while others present significant changes in their gene expression, probably induced by the treatment. CTGF and DUSP1 overexpression in residual samples may be a reflection of resistance to further administration of AC regimen.

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The objective of this study is to characterize the lipoprotein risk levels in Takayasu arteritis (TA) patients and its possible association with disease activity and glucocorticoid use. Twenty-five female TA patients were consecutively included and compared with 30 age-, gender-, and body mass index-matched healthy controls. Demographic features and the lipid profile were determined and cardiovascular risk levels were evaluated according to NCEP/ATPIII. Total cholesterol (TC), LDL-c, HDL-c, and triglycerides were determined after a 12-h overnight fast. Exclusion criteria were conditions that interfere in the lipid profile. The disease duration was 6.6 +/- 7.4 years; 30% had clinical activity and 80% had laboratory activity. Regarding NCEP/ATPIII risk levels, TA patients presented higher frequency of lipid risk compared to controls: high TC (48% vs. 20%, p = 0.04), low HDL-c (20% vs. 0%, p = 0.015), and high triglycerides (36% vs. 10%, p = 0.026). No difference was observed related to LDL-c risk levels between both groups (40% vs. 20%, p = 0.14). Remarkably, 60% of the patients had at least one lipid risk factor for cardiovascular disease. No difference in the lipids was observed between patients with and without clinical activity; however, those with laboratory activity showed lower levels of HDL-c (1.37 +/- 0.42 vs. 2.00 +/- 0.63 mmol/L, p = 0.012) than patients without this activity. A negative correlation was found between HDL-c and CRP levels (r = -0.42, p = 0.04). Lipids were similar in patients under glucocorticoid compared to those without this therapy. This is the first study to identify that TA, an inflammatory disease, has a proatherogenic lipid profile which is associated to laboratory disease activity.

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Obstructive sleep apnea (OSA) has emerged as an independent risk factor for atherosclerosis. However, OSA is frequently associated with several risk factors for atherosclerosis, including hypertension (HTN). The impact of OSA and HTN alone compared with the association of both conditions on carotid atherosclerosis is not understood. We studied 94 middle-aged participants free of smoking and diabetes mellitus who were divided into 4 groups: controls (n = 22), OSA (n = 25), HTN (n = 20), and OSA + HTN (n = 27). All of the participants underwent polysomnography and carotid measurements of intima-media thickness, diameter, and distensibility with an echo-tracking device. Compared with controls, intima-media thickness and carotid diameter were similarly higher in OSA (713 +/- 117 and 7117 +/- 805 mu m), and HTN groups (713 +/- 182 and 7191 +/- 818 mu m), with a further significant increase in OSA + HTN patients (837 +/- 181 and 7927 +/- 821 mu m, respectively; P < 0.01). Carotid distensibility was significantly lower in HTN (P < 0.05) and OSA + HTN subjects (P < 0.001) compared with controls. In the OSA + HTN group, carotid distensibility was significantly lower than in the OSA group and controls (P < 0.05 for each comparison). Multivariate analysis showed that intima-media thickness was positively related to systolic blood pressure and apnea-hypopnea index. Apnea-hypopnea index was the only factor related to carotid diameter. Age and systolic blood pressure were independently related to carotid distensibility. In conclusion, the association of OSA and HTN has additive effects on markers of carotid atherosclerosis. Because early markers of carotid atherosclerosis predict future cardiovascular events, including not only stroke but also myocardial infarction, these findings may help to explain the increased risk of cardiovascular disease in patients with OSA. (Hypertension. 2009; 53: 64-69.)

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Low birth weight and preterm birth, and social disadvantage may negatively affect mental health of children, but findings have been inconsistent. To assess the influence of perinatal and social factors on mental health problems in children aged 7-9 years. A random sample of 805 births in So Luis, Brazil was studied in 1997/1998 and again in 2005/2006. Perinatal, socioeconomic and demographic variables were assessed within 24 h after delivery. The Strengths and Difficulties Questionnaire (SDQ) was used to assess mental health problems in the children. Simple and multiple Poisson regressions were used for statistical analysis. The overall prevalence of mental health problems in the total sample was 47.7%. The prevalences of emotional and conduct problems were 58.2 and 48.8%, respectively. Only paternal age (< 20 years) was associated with mental health problems as measured by the full SDQ scale (prevalence ratio PR = 1.27). Children born to single mothers (PR = 1.31) and those with birth weight from 1,500 to 2,499 g (PR = 1.18) and from 2,500 to 2,999 g (PR = 1.17) had a higher risk of emotional problems, but those from low income families had a lower risk (PR = 0.80). Children with a father of less than 20 years had a higher risk of having problems with their peers (PR = 1.75). A maternal education of 9 years or over was inversely associated with peer (PR = 0.70) and conduct problems (PR = 0.73). Girls had a lower risk of conduct (PR = 0.77) and hyperactivity problems (PR = 0.68). A maternal education of 4 years or less increased the risk of hyperactivity (PR = 1.48). Socioeconomic and demographic conditions were better predictors of mental health problems in children than birth weight or preterm birth. However, since most effect sizes were small most mental health problems were, unexplained by the variables in the study.

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Objectives To introduce a comprehensive and reliable scoring system for the assessment of whole-knee joint synovitis based on contrast-enhanced (CE) MRI. Methods Multicenter Osteoarthritis Study (MOST) is a cohort study of people with, or at high risk of, knee osteoarthritis (OA). Subjects are an unselected subset of MOST who volunteered for CE-MRI. Synovitis was assessed at 11 sites of the joint. Synovial thickness was scored semiquantitatively: grade 0 (< 2 mm), grade 1 (2-4 mm) and grade 2 (> 4 mm) at each site. Two musculoskeletal radiologists performed the readings and inter-and intrareader reliability was evaluated. Whole-knee synovitis was assessed by summing the scores from all sites. The association of Western Ontario and McMaster Osteoarthritis Index pain score with this summed score and with the maximum synovitis grade for each site was assessed. Results 400 subjects were included (mean age 58.8 +/- 7.0 years, body mass index 29.5 +/- 4.9 kg/m(2), 46% women). For individual sites, intrareader reliability (weighted kappa) was 0.67-1.00 for reader 1 and 0.60-1.00 for reader 2. Inter-reader agreement (kappa) was 0.67-0.92. For the summed synovitis scores, intrareader reliability (intraclass correlation coefficient (ICC)) was 0.98 and 0.96 for each reader and inter-reader agreement (ICC) was 0.94. Moderate to severe synovitis in the parapatellar subregion was associated with the higher maximum pain score (adjusted OR (95% CI), 2.8 (1.4 to 5.4) and 3.1 (1.2 to 7.9), respectively). Conclusions A comprehensive semiquantitative scoring system for the assessment of whole-knee synovitis is proposed. It is reliable and identifies knees with pain, and thus is a potentially powerful tool for synovitis assessment in epidemiological OA studies.

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Noradrenaline has been shown to modulate the ovarian-steroid feedback on luteinising-hormone (LH) release. However, despite the high amount of evidence accumulated over many years, the role of noradrenaline in LH regulation is still not clearly understood. The present study aimed to further investigate the involvement of noradrenaline in the negative-feedback effect of oestradiol and progesterone on basal LH secretion. In experiment 1, ovariectomised (OVX) rats received a single injection of oil, oestradiol, or progesterone at 09.00-10.00 h and were decapitated 30 or 60 min later. Levels of noradrenaline and its metabolite, 3-methoxy-4-hydroxyphenylglycol (MHPG), were determined in microdissections of the preoptic area (POA) and medial basal hypothalamus-median eminence (MBH-ME) and correlated with LH secretion. Basal LH levels were decreased 30 and 60 min after oestradiol or progesterone injection, and this hormonal response was significantly correlated with a reduction in POA MHPG levels, which reflect noradrenaline release. In addition, noradrenaline levels in the POA were increased, whereas noradrenaline turnover (MHPG/noradrenaline ratio) was decreased 60 min after the injection of both hormones. No effect was found in the MBH-ME. In experiment 2, i.c.v. administration of noradrenaline (60 nmol), performed 15 min before oestradiol or progesterone injection in jugular vein-cannulated OVX rats, completely prevented the ovarian steroid-induced inhibition of LH secretion. The data obtained provide direct evidence that LH secretion in OVX rats is positively regulated by basal noradrenergic activity in the POA, and its reduction appears to play a role in the negative-feedback effect of ovarian steroids on LH secretion in vivo.

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The spatial and temporal variations of Ross River virus infections reported in Queensland, Australia, between 1985 and 1996 were studied by using the Geographic Information System. The notified cases of Ross River virus infection came from 489 localities between 1985 and 1988, 805 between 1989 and 1992, and 1,157 between 1993 and 1996 (X (2)((df = 2)) = 680.9; P < 0.001). There was a marked increase in the number of localities where the cases were reported by 65 percent for the period of 1989-1992 and 137 percent for 1993-1996, compared with that for 1985-1988. The geographic distribution of the notified Ross River virus cases has expanded in Queensland over recent years. As Ross River virus disease has impacted considerably on tourism and industry, as well as on residents of affected areas, more research is required to explore the causes of the geographic expansion of the notified Ross River virus infections.

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Calcium precipitation can have a number of effects on the performance of high-rate anaerobic performance including cementing of the sludge bed, limiting diffusion, and diluting the active biomass. The aim of this study was to observe the influence of precipitation in a stable full-scale system fed with high-calcium paper factory wastewater. Granules were examined from an upflow anaerobic sludge blanket reactor (volume 1,805 m(3)) at a recycled paper mill with a loading rate of 5.7-6.6 kgCOD.m(-3).d(-1) and influent calcium concentration of 400-700 gCa(.)m(-3). The granules were relatively small (1 mm), with a 200-400 mum core of calcium precipitate as observed with energy dispersive X-ray spectroscopy. Compared to other granules, Methanomicrobiales not Methanobacteriales were the dominant hydrogen or formate utilisers, and putative acidogens were filamentous. The strength of the paper mill fed granules was very high when compared to granules from other full-scale reactors, and a partial linear correlation between granule strength and calcium concentration was identified.

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O texto sintetiza os principais fundamentos do m??todo PES. Esse m??todo contrap??e-se ao planejamento tradicional e prop??e uma abordagem tecnopol??tica do planejamento.

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Este trabalho consiste em aplicar o princípio do indeterminismo metodológico na Ciência Econômica. Isto implica definir dois tipos de universo econômico: um que se caracteriza pela ergodicidade e pela reversibilidade do tempo e dos processos econômicos, e o outro pelas características contrárias. Uma primeira parte tratará da construção do objeto de estudo e da natureza da análise relativa a cada um desses universos. Em razão desta dicotomia, uma segunda parte estudará suas implicações no que diz respeito à natureza das probabilidades e dos processos que guiam as decisões dos agentes.

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Resumo: 1- Introdução: algumas notícias da comunicação social; 2 – O designado «Conselho de Prevenção de Corrupção»; 3 – Procuradoria-Geral da República (P.G.R.) e o Departamento Central de Investigação e Acção Penal (D.I.A.P.); 4 – Alguns sítios com relevo; 5 – Alguns dos problemas que podem ser colocados em relação à Responsabilidade das Empresas pelo Crime de Corrupção; 5.1 – Âmbito dos problemas a serem falados; 6 – Qual a noção de «empresas que vamos utilizar»?; 6.1 – A noção de «empresa» em sentido geral objectivo e penal; 7 – Mas que tipo de crimes de corrupção vamos falar?; 8 – O art. 11º do Código Penal e os crimes de corrupção no contexto do ordenamento jurídico português; 8.1 – No contexto do art. 11º do Código Penal, o que significa «em nome da pessoa colectiva»?; 8.2 – No contexto do art. 11º do Código Penal, o que significa «no interesse da pessoa colectiva»?; 8.2.1 – No contexto do art. 11º do Código Penal, o que significa «quando não há interesse colectivo»?; 9 – E haverá diferenças, por exemplo, entre o modo de funcionamento técnico-jurídico do art. 11º do Código Penal e o art. 3º do Regime das Infracções Anti-Económicas e Contra a Saúde Pública (R.I.A.E.C.S.P.)?; 10 – E como é que a Jurisprudência portuguesa, a que tivemos acesso - dado não haver ainda fartura de decisões neste campo -, estabelece o nexo de imputação de responsabilidade penal a uma pessoa colectiva e/ou organização?; 10.1 – Uma primeira pré-conclusão dentro do objectivo que pretendemos demonstrar na totalidade deste trabalho; 11 – Uma segunda pré-conclusão: será que as diferenças acima assinaladas, por exemplo, entre o modo de funcionamento técnico-jurídico do art. 11º do Código Penal e o art. 3º do Regime das Infracções Anti-Económicas e Contra a Saúde Pública (R.I.A.E.C.S.P.), são as únicas? Veja-se o caso, v.g., do art. 7º do Regime Geral das Infracções Tributárias (R.G.I.T.); 12 – Em face das duas pré-conclusões anteriores, faça-se aqui, neste breve ensaio, uma primeira grande conclusão; 13 – Uma (primeira) hipótese de solução; 14 – Que tipo de «empresa» podemos enquadrar no art. 11º do Código Penal?; 14.1 – De acordo com o referido anteriormente, podemos dizer que todas as «empresas» podem praticar os crimes previstos e punidos no Código Penal português?; 14.2 – De acordo com o referido antes, quais são as «empresas» que não podem praticar os crimes de corrupção que estão previstos e punidos no Código Penal português?; 14.3 – Uma outra pré-conclusão: 14.4 – Um esboço de um dos possíveis problemas; 14.4.1 – Mas, afinal, o que são Entidades Públicas Empresariais (E.P.E.)?; 14.5 – Outra hipótese de esboço de um outro dos possíveis problemas que aqui podemos encontrar; 14.6 – Nova pré-conclusão; 14.7 – Uma outra importante pergunta a fazer e a responder desde já; 14.7.1 - Alarguemos, pois, um pouco a nossa investigação para além do Código Penal português; 14.7.2 – O problema da responsabilidade penal das organizações e/ou «pessoas colectivas», rectius, neste breve ensaio, empresas, pela prática de crimes de corrupção previstos e punidos na mencionada Lei n.º 20/2008, de 21 de Abril («Responsabilidade penal por crimes de corrupção no comércio internacional e na actividade privada»); 14.7.3 – Mais algumas pré-conclusões; 15 - Em face das duas pré-conclusões anteriores, faça-se aqui, neste breve ensaio, uma segunda grande conclusão; 16 - O que também apresenta outras implicações como por exemplo na aplicação do crime de «branqueamento» quando nos fala em «corrupção» como «crime primário»; 17 – Outras interrogações; 18 – Conclusão final, mas não última, como nenhuma o pode ser em ciência; 19 – Hipótese de solução. § Abstract: 1 - Introduction: some news media; 2 - The so-called "Council for the Prevention of Corruption”, 3 – “Attorney General's Office” (PGR) and the Central Bureau of Investigation and Penal Action (DIAP) 4 - Some sites with relief , 5 - Some of the problems that can be placed in relation to the Corporate Responsibility of the Crime of Corruption; 5.1 - Scope of issues to be spoken, 6 - What is the concept of "companies that we will use"?; 6.1 - The term “business” in a general purpose and criminal matters; 7 - What kind of crimes of corruption we talking about?; 8 - Art. 11 of the Penal Code and the crimes of corruption in the context of the Portuguese legal system; 8.1 - In the context of art. 11 of the Penal Code, which means "in the name of the legal person"?; 8.2 - In the context of art. 11 of the Penal Code, which means “in the interests of the legal person"?; 8.2.1 - In the context of art. 11 of the Penal Code, which means "where there is no collective interest"?; 9 - There will be differences, for example, between the operating mode of the Art. 11 of the Criminal Code and Art. 3 of the Legal Infractions Anti-Economic and Against Public Health (RIAECSP)?; 10 - And how does the case law of Portugal, we had access - as there still plenty of decisions in this field - makes a connection of allocating criminal liability to a legal person and / or organization?; 10.1 - A first pre-completion within the objective that we intend to demonstrate in all of this work; 11 - A second pre-conclusion: that the differences will be noted above, for example, between operating mode of the Art. 11 of the Criminal Code and Art. 3 of the Rules of the Offences Against Anti-Economics and Public Health (RIAECSP) are the only ones? Take the case v.g. of art. 7 of the Legal Framework of Tax Offences (RGIT) 12 - In view of the two pre-earlier conclusions, do it here, in this brief essay, a first major conclusion; 13 - A (first) chance for a solution, 14 - What kind “undertaking” we can frame the art. 11 of the Penal Code?; 14.1 - According to the above, we can say that all "companies" can practice the crimes defined and punished in the Portuguese Penal Code?; 14.2 - According to the mentioned before, what are the "business" who cannot practice corruption crimes that are planned and punished the Portuguese Penal Code?; 14.3 - Another pre-completion: 14.4 - A sketch of one of the possible problems; 14.4.1 - But after all the entities that are Public Enterprise (EPE)?; 14.5 - Another chance to draft another one of the possible problems that can be found here; 14.6 - New pre-completion; 14.7 - Another important question to ask and answer now; 14.7.1 - Let us expand, then, a little beyond our investigation of the Portuguese Penal Code; 14.7.2 - The problem of criminal liability of organizations and / or "legal persons", rectius, this brief essay, companies, for crimes of corruption provided for and punished mentioned in Law No. 20/2008 of 21 April ("Criminal liability for crimes of corruption in international trade and private activities"); 14.7.3 - Some more pre-conclusions; 15 - In view of the two pre-earlier conclusions, let it be here in this brief essay, a second major conclusion, 16 - Who also has other implications such as the application of the crime of "money laundering" when we talk about “corruption” as “primary crime”, 17 - Other questions; 18 - Bottom line, but not last, as the can be no science; 19 - Hypothesis solution. Abstract como no livro.

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Cada vez mais os indivíduos necessitam de competências digitais avançadas para participar plenamente na sociedade. Numa Europa em crescente envelhecimento é atualmente reconhecida a importância e o potencial da indústria de serviços para envelhecer bem baseados nas tecnologias de informação e de comunicação (TIC), de que é exemplo o mercado eletrónico de serviços sociais e de cuidados de saúde, o GuiMarket, proposto pelos autores para um município do Norte de Portugal. Com base nos resultados de um inquérito realizado junto de uma amostra de 315 indivíduos, o artigo discute a importância reconhecida a tal serviço e a frequência de utilização prevista, concluindo existir uma íntima relação entre o acesso às TIC e a utilização que os inquiridos preveem fazer do GuiMarket.

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Apesar de quase onipresente nos trabalhos de estratégia e áreas correlatas, o conceito de vantagem competitiva continua sendo foco de debate na academia por não possuir uma definição aceita por consenso. Uma manifestação disso é a recente discussão quanto aos seus fundamentos lógicos e filosóficos, e o questionamento de sua própria existência. O presente trabalho oferece uma proposta de definição constitutiva e operacional de vantagem competitiva que possibilita o desenvolvimento de uma métrica. Essa métrica é aplicada em um trabalho empírico que mede a vantagem competitiva de 2.805 empresas em 16 países, com um total de 13.259 observações. O trabalho demonstra que a existência da vantagem competitiva não é um fato raro, e que cerca de 10% a 12% das empresas analisadas apresentam uma vantagem competitiva estatisticamente significativa, enquanto que uma porcentagem similar apresenta uma desvantagem competitiva igualmente significativa.