Skewness, splitting number and vertex deletion of some toroidal meshes

The skewness sk(G) of a graph G = (V, E) is the smallest integer sk(G) >= 0 such that a planar graph can be obtained from G by the removal of sk(C) edges. The splitting number sp(G) of C is the smallest integer sp(G) >= 0 such that a planar graph can be obtained from G by sp(G) vertex splitting operations. The vertex deletion vd(G) of G is the smallest integer vd(G) >= 0 such that a planar graph can be obtained from G by the removal of vd(G) vertices. Regular toroidal meshes are popular topologies for the connection networks of SIMD parallel machines. The best known of these meshes is the rectangular toroidal mesh C(m) x C(n) for which is known the skewness, the splitting number and the vertex deletion. In this work we consider two related families: a triangulation Tc(m) x c(n) of C(m) x C(n) in the torus, and an hexagonal mesh Hc(m) x c(n), the dual of Tc(m) x c(n) in the torus. It is established that sp(Tc(m) x c(n)) = vd(Tc(m) x c(n) = sk(Hc(m) x c(n)) = sp(Hc(m) x c(n)) = vd(Hc(m) x c(n)) = min{m, n} and that sk(Tc(m) x c(n)) = 2 min {m, n}.

Double disruption of alpha(2A)- and alpha(2C)-adrenoceptors results in sympathetic hyperactivity and high-bone-mass phenotype

Evidence demonstrates that sympathetic nervous system (SNS) activation causes osteopenia via beta(2)-adrenoceptor (beta(2)-AR) signaling. Here we show that female mice with chronic sympathetic hyperactivity owing to double knockout of adrenoceptors that negatively regulate norepinephrine release, alpha(2A)-AR and alpha(2C)-AR(alpha(2A)/alpha(2C)-ARKO), present an unexpected and generalized phenotype of high bone mass with decreased bone resorption and increased formation. In alpha(2A)/alpha(2C)-ARKO versus wild-type (WT) mice, micro-computed tomographic (mu CT) analysis showed increased, better connected, and more plate-shaped trabeculae in the femur and vertebra and increased cortical thickness in the vertebra, whereas biomechanical analysis showed increased tibial and femoral strength. Tibial mRNA expression of tartrate-resistant acid phosphatase (TRACP) and receptor activator of NF-kappa B (RANK), which are osteoclast-related factors, was lower in knockout (KO) mice. Plasma leptin and brain mRNA levels of cocaine amphetamine-regulated transcript (CART), which are factors that centrally affect bone turnover, and serum levels of estradiol were similar between mice strains. Tibial beta(2)-AR mRNA expression also was similar in KO and WT littermates, whereas alpha(2A)-, alpha(2B)- and alpha(2C)-AR mRNAs were detected in the tibia of WT mice and in osteoblast-like MC3T3-E1 cells. By immunohistochemistry, we detected alpha(2A)-, alpha(2B)-, alpha(2C)- and beta(2)-ARs in osteoblasts, osteoclasts, and chondrocytes of 18.5-day-old mouse fetuses and 35-day-old mice. Finally, we showed that isolated osteoclasts in culture are responsive to the selective alpha(2)-AR agonist clonidine and to the nonspecific alpha-AR antagonist phentolamine. These findings suggest that beta(2)-AR is not the single adrenoceptor involved in bone turnover regulation and show that alpha(2)-AR signaling also may mediate the SNS actions in the skeleton. (c) 2011 American Society for Bone and Mineral Research.

Knowledges and practices of successful literacy teachers (Brazil, 1950-1980)

Significant changes have marked Brazilian education in the period focused on by this research. Aiming to understand the configurations of the teaching profession in that period, this work focuses on the issue of the school success in the area of literacy by means of an analysis of the practices of literacy teachers who were at work between the 1950s and 1980s. The research is based on life-history accounts. The study aimed at describing the various experiences of these teachers identifying the knowledges and practices that sustained their successful literacy work as well as the various factors of a social, religious, political, familiar or other nature that, in the history of each of these teachers, favoured the development of a pedagogical style of literacy particular to each one of them. Despite the peculiarities and originality of each history, the success in the literacy process, as the defining feature of the profile of the four teachers, results from two main aspects: first, the autonomy that each one managed to keep in the development of his/her teaching work, particularly in the organisation of the teaching practices that indicated greater chances of a pupil`s learning to read and write; second, their trust in the capacity of every child for learning, independently of his/her social, economic and cultural conditions. Based on this evidence it is argued that the success of the pedagogical work, particularly during the early years of schooling, lies in an ethics of the teaching work with a double implication: first, it requires the teachers` dedication to their pupils, and second, it requires respect for the work of the teacher, so that she/he can maintain her/his autonomy and inventiveness. These aspects indicate the need for reflection on teaching work and a review of current teacher education policies, particularly the policies targeted at teachers working with literacy practices.

Teacher strikes in Brazil and its representations: ""orderly disciplined class"" and ""education workers"" (Sao Paulo, 1963-1979)

This article analyses the teacher strikes that took place in the state of Sao Paulo ( Brazil). These strikes produced new representations of the profession and gave a particular visibility to its interest aggregation processes. These same strikes appeared as major incentives for the organisation of teachers in Brazil. The October 1963 strike - about six months before the military coup of 1964 - was the first to mobilise the whole of the teaching profession of the Sao Paulo state: primary and secondary education, public and private schools were all involved. The two other strikes, organised by teachers in the public schools in 1978 and 1979, took place under the dictatorship. As such, they had a particular significance in the process of recovering civil liberties in the final stages of the military regime in the 1980s. This article is based on an analysis of the front-page covering of these teacher strikes by the two major journals of the state, O Estado de S. Paulo and Folha de S. Paulo. With Chartier`s concept collective representations in mind, this approach allows us to grasp how large-circulation journals diffuse images of the profession and its organisational configurations. These press pictures are analysed by dint of the analytical frame Roland Barthes advanced in the 1960s, i.e. by reading their denoted, connoted and symbolic messages.

The contribution of classical (beta(1/2)-) and atypical beta-adrenoceptors to the stimulation of human white adipocyte lipolysis and right atrial appendage contraction by novel beta(3)-adrenoceptor agonists of differing selectivities

The role of beta(3)- and other putative atypical beta-adrenaceptors in human white adipocytes and right atrial appendage has been investigated using CGP 12177 and novel phenylethanolamine and aryloxypropanolamine beta(3)-adrenoceptor (beta(3)AR) agonists with varying intrinsic activities and selectivities for human cloned PAR subtypes. The ability to demonstrate beta(1/2)AR antagonist-insensitive (beta(3) or other atypical beta AR-mediated) responses to CGP 12177 was critically dependent on the albumin batch used to prepare and incubate the adipocytes. Four aryloxypropanolamine selective beta(3)AR agonists (SB-226552, SB-229432, SB-236923, SB-246982) consistently elicited beta(1/2)AR antagonist-insensitive lipolysis. However, a phenylethanolamine (SB-220646) that was a selective full beta(3)AR agonist elicited full lipolytic and inotropic responses that were sensitive to beta(1/2)AR antagonism, despite it having very low efficacies at cloned beta(1)- and beta(2)ARs. A component of the response to another phenylethanolamine selective beta(3)AR agonist (SB-215691) was insensitive to beta(1/2)AR antagonism in some experiments. Because novel aryloxypropanolamine had a beta(1/2)AR antagonist-insensitive inotropic effect, these results establish more firmly that beta(3)ARs mediate lipolysis in human white adipocytes, and suggest that putative 'beta(4)ARs' mediate inotropic responses to CGP 12177. The results also illustrate the difficulty of predicting from studies on cloned beta ARs which beta ARs will mediate responses to agonists in tissues that have a high number of beta(1)- and beta(2)ARs or a low number of beta(3)ARs.

Two new arsenate/sulfate-reducing bacteria: mechanisms of arsenate reduction

Two sulfate-reducing bacteria, which also reduce arsenate, were isolated; both organisms oxidized lactate incompletely to acetate. When using lactate as the electron donor, one of these organisms, Desulfomicrobium strain Ben-RB, rapidly reduced (doubling time = 8 h) 5.1 mM arsenate at the same time it reduced sulfate (9.6 mM). Sulfate reduction was not inhibited by the presence of arsenate. Arsenate could act as the terminal electron acceptor in minimal medium (doubling time = 9 h) in the absence of sulfate. Arsenate was reduced by a membrane-bound enzyme that is either a c-type cytochrome or is associated with such a cytochrome; benzyl-viologen- dependent arsenate reductase activity was greater in cells grown with arsenate/sulfate than in cells grown with sulfate only. The second organism, Desulfovibrio strain Ben-RA, also grew (doubling time = 8 h) while reducing arsenate (3.1 mM) and sulfate (8.3 mM) concomitantly. No evidence was found, however, that this organism is able to grow using arsenate as the terminal electron acceptor. Instead, it appears that arsenate reduction by the Desulfovibrio strain Ben-RA is catalyzed by an arsenate reductase that is encoded by a chromosomally-borne gene shown to be homologous to the arsC gene of the Escherichia coli plasmid, R773 ars system.

Subtype-selective noncompetitive or competitive inhibition of human alpha(1)-adrenergic receptors by rho-TIA

The 19-amino acid conopeptide (rho-TIA) was shown previously to antagonize noncompetitively alpha(1B)-adrenergic receptors (ARs). Because this is the first peptide ligand for these receptors, we compared its interactions with the three recombinant human alpha(1)-AR subtypes (alpha(1A), alpha(1B), and alpha(1D)). Radioligand binding assays showed that rho-TIA was 10-fold selective for human alpha(1B)- over alpha(1A)- and alpha(1D)-ARs. As observed with hamster alpha(1B)-ARs, rho-TIA decreased the number of binding sites (B-max) for human alpha(1B)-ARs without changing affinity (K-D), and this inhibition was unaffected by the length of incubation but was reversed by washing. However, rho-TIA had opposite effects at human alpha(1A)-ARs and alpha(1D)-ARs, decreasing KD without changing Bmax, suggesting it acts competitively at these subtypes. rho-TIA reduced maximal NE-stimulated [H-3] inositol phosphate formation in HEK293 cells expressing human alpha(1B)-ARs but competitively inhibited responses in cells expressing alpha(1A)- or alpha(1D)-ARs. Truncation mutants showed that the amino-terminal domains of alpha(1B)- or alpha(1D)-ARs are not involved in interaction with rho-TIA. Alanine-scanning mutagenesis of rho-TIA showed F18A had an increased selectivity for alpha(1B)-ARs, and F18N also increased subtype selectivity. I8A had a slightly reduced potency at alpha(1B)-ARs and was found to be a competitive, rather than noncompetitive, inhibitor in both radioligand and functional assays. Thus rho-TIA noncompetitively inhibits alpha(1B)-ARs but competitively inhibits the other two subtypes, and this selectivity can be increased by mutation. These differential interactions do not involve the receptor amino termini and are not because of the charged nature of the peptide, and isoleucine 8 is critical for its noncompetitive inhibition at alpha(1B)-ARs.

Education and the historiography of Ibero-American independence: elusive presences, many absences

This contribution analyses recent historiographical tendencies in research in the field of education at the time of the political emancipation of the former Spanish and Portuguese colonies in Latin America. The article briefly presents the complex educational scene in Latin America on the eve of the movements for independence. Due to the revolutionary character of the process of independence, it identifies educational history as one of the most significant absences in the historiography of independence. Notwithstanding, education has certainly been addressed by historians of education, mostly focusing on the colonial or postcolonial period, while largely neglecting the two decades after 1808. This indicates both the divide prevalent between historians of education and historians of independence and the rather nationalistic conceptual frame of existing scholarship.

The mu-way intersection problem for m-cycle systems

An m-cycle system of order upsilon is a partition of the edge-set of a complete graph of order upsilon into m-cycles. The mu -way intersection problem for m-cycle systems involves taking mu systems, based on the same vertex set, and determining the possible number of cycles which can be common to all mu systems. General results for arbitrary m are obtained, and detailed intersection values for (mu, m) = (3, 4), (4, 5),(4, 6), (4, 7), (8, 8), (8, 9). (For the case (mu, m)= (2, m), see Billington (J. Combin. Des. 1 (1993) 435); for the case (Cc,m)=(3,3), see Milici and Quattrochi (Ars Combin. A 24 (1987) 175. (C) 2001 Elsevier Science B.V. All rights reserved.

Murine ventricular L-type Ca2+ current is enhanced by zinterol via beta(1)-adrenoceptors, and is reduced in TG4 mice overexpressing the human beta(2)-adrenoceptor

1 The functional coupling of B-2-adrenoceptors (beta (2)-ARs) to murine L-type Ca2+ current (I-Ca(L)) was investigated with two different approaches. The beta (2)-AR signalling cascade was activated either with the beta (2)-AR selective agonist zinterol (myocytes from wild-type mice), or by spontaneously active, unoccupied beta (2)-ARs (myocytes from TG4 mice with 435 fold overexpression of human beta (2)-ARs). Ca2+ and Ba2+ currents were recorded in the whole-cell and cell-attached configuration of the patch- clamp technique, respectively. 2 Zinterol (10 muM) significantly increased I-Ca(L) amplitude of wild-type myocytes by 19+/-5%, and this effect was markedly enhanced after inactivation of Gi-proteins with pertussis-toxin (PTX; 76+/-13% increase). However, the effect of zinterol was entirely mediated by the beta (1)-AR subtype, since it was blocked by the beta (1)-AR selective antagonist CGP 20712A (300 nM). The beta (2)-AR selective antagonist ICI 118,551 (50 nM) did not affect the response of I-Ca(L) to zinterol. 3 In myocytes with beta (2)-AR overexpression I-Ca(L) was not stimulated by the activated signalling cascade. On the contrary, I-Ca(L) was lower in TG4 myocytes and a significant reduction of single-channel activity was identified as a reason for the lower whole-cell I-Ca(L). The beta (2)-AR inverse agonist ICI 118,551 did not further decrease I-Ca(L). PTX-treatment increased current amplitude to values found in control myocytes. 4 In conclusion, there is no evidence for beta (2)-AR mediated increases of I-Ca(L) in wild-type mouse ventricular myocytes. Inactivation of Gi-proteins does not unmask beta (2)-AR responses to zinterol, but augments beta (1)-AR mediated increases of I-Ca(L). In the mouse model of beta (2)-AR overexpression I-Ca(L) is reduced due to tonic activation of Gi-proteins.

Parties, governments and pollsters: A new form of patronage?

In its first term, the Howard government hired Australasian Research Strategies (ARS), headed by pollster Mark Textor, to conduct market research for several Commonwealth departments and agencies. This was, the Labor Opposition claimed, a case of the Liberals handing jobs to their 'mates'. Textor played a key role in the Liberals' 1996 and 1998 federal election campaigns. However, Labor's attack rings hollow since in the 1980s the Hawke government similarly contracted Rod Cameron's ANOP to conduct opinion research for Commonwealth departments and agencies. At the time Cameron was Labor's strategic pollster and centrally involved in planning Labor election campaigns. On both sides of Australian politics, governments have begun to channel patronage towards their party's pollsters. In this research note, we suggest that this development cannot be explained as 'jobs for the boys'. Instead, this new form of patronage has its roots in the vital role that pollsters now play in guiding election campaigns, and in the commercial reality that Australian politics provides too little work to sustain specialist political pollsters. Parties in government now appear to utilise incumbency to sustain an ongoing relationship with the commercial polling organisations like ANOP and ARS to whom they will entrust much of the planning of their campaign for re-election.

Conservation of the cardiostimulant effects of (-)-Norepinephrine across Ser49Gly and Gly389Arg Beta1-adrenergic receptor polymorphisms in human right atrium in vitro

OBJECTIVES The goal of this study was to determine whether the cardiostimulant effects of the endogenous beta(1)-adrenergic receptor (AR) agonist, (-)-norepinephrine are modified by polymorphic (Serine49Glycine [Ser49Gly], Glycine389Arginine [Gly389Arg]) variants of beta(1)-ARs in the nonfailing adult human heart. BACKGROUND Human heart beta(1)-ARs perform a crucial role in mediating the cardiostimulant effects of (-)-norepinephrine. An understanding of the significance of Ser49Gly and Gly389Arg polymorphisms in the human heart is beginning to emerge, but not as yet in adult patients who have coronary artery disease (CAD). METHODS The potency and maximal effects of (-)-norepinephrine at beta(1)-ARs (in the presence of beta(2)-AR blockade with 50 nM ICI 118,551 [erythro-DL-1(7-methylindan-4-yloxy)-3-isopropylamino-butan-2-ol]) for changes in contractile force and shortening of contractile cycle duration were determined in human right atrium in vitro from 87 patients undergoing coronary artery bypass grafting who were taking beta-blockers before surgery. A smaller sample of patients (n = 20) not taking beta-blockers was also investigated. Genotyping for two beta(1)-AR polymorphisms (Ser49Gly and Gly389Arg) was determined from a sample of blood taken at the time of surgery. RESULTS (-)-Norepinephrine caused concentration-dependent increases in contractile force and reductions in time to reach peak force and time to reach 50% relaxation. There were no differences in the potency or maximal effects of (-)-norepinephrine in the right atrium from patients with different Ser49Gly and Gly389Arg polymorphisms. CONCLUSIONS The cardiostimulant effects of (-)-norepinephrine at beta(1)-ARs were conserved across Ser49Gly and Gly389Arg polymorphisms in the right atrium of nonfailing hearts from patients with CAD managed with or without beta-blockers. (C) 2002 by the American College of Cardiology Foundation.

Hemorragia pós-operatória em 397 adenotonsilectomias realizadas nos Hospitais Geral de Pirajussara (HGP) e Hospital Estadual de Diadema (HED) / UNIFESP-EPM

As adenotonsilectomias são cirurgias freqüentes na especialidade de otorrinolaringologia, e sua principal indicação é a hipertrofia das tonsilas palatinas e faríngeas. Sua complicação mais comum é a hemorragia. Em nosso trabalho apresentamos a incidência de hemorragia pós-operatória das adenotonsilectomias realizadas no Hospital Geral de Pirajussara (HGP) e Hospital Estadual de Diadema (HED), objetivando a identificação das causas de sangramento. FORMA DE ESTUDO: Coorte transversal historica. MATERIAL E MÉTODO: Foram avaliados 397 pacientes submetidos a cirurgias de adenoidectomias, tonsilectomias palatinas e adenotonsilectomias. Estas últimas representaram 91,7% do total. A idade dos pacientes variou de 2 a 39 anos. Foi realizada triagem pré-operatória através de exames laboratoriais em todos os pacientes e os mesmos foram acompanhados em retornos semanais até o primeiro mês de pós-operatório. RESULTADOS: Foram realizadas nos dois hospitais (HGP e HED) 397 cirurgias, sendo 364 adenotonsilectomias (91,7%), 16 tonsilectomias palatinas (4,03%) e 17 adenoidectomias (4,28%). Houve 5 casos de sangramento no pós-operatório, sendo 3 no período imediato e 2 no período mediato. Não ocorreu nenhum caso de hemorragia no período tardio. A incidência de hemorragia, portanto, foi de 1,37% (5 casos em 364). CONCLUSÃO: a hemorragia pós-operatória parece estar relacionada com a dificuldade técnica da cirurgia e alterações da hemostasia encontradas em alguns pacientes.

Valor prognóstico de dados clínicos em paralisia de Bell

Com o advento dos testes eletrofisiológicos, a avaliação clínica parece ter perdido interesse na paralisia de Bell. A eletroneuronografia (ENoG) associada ao estadiamento clínico da doença é o método mais freqüentemente utilizado para mensurar o prognóstico da paralisia de Bell. Entretanto, a ENoG constitui-se em um teste eletrofisiológico ainda não universalmente disponível, especialmente nos serviços de emergência. OBJETIVO: Estudar a medida do prognóstico da paralisia de Bell com base nos dados clínicos e no teste de estimulação elétrica mínima, teste de Hilger, permitindo assim uma previsão de prognóstico segura e factível na maioria dos serviços. FORMA DE ESTUDO: coorte historica. MATERIAL E MÉTODO: Estudo coorte retrospectivo, analisando 1521 casos de paralisia de Bell, correlacionando-se os dados clínicos sexo, idade, lado da paralisia, modo de instalação, sintomas prévios, sintomas associados e os resultados do teste de estimulação elétrica mínima (Hilger), com a evolução da paralisia após 6 meses. RESULTADO: O estudo desses dados indicou que pacientes acima de 60 anos apresentaram prognóstico pior em comparação com pacientes com idade abaixo de 30 anos; o modo de instalação progressiva, a ausência de sintomas prévios, a presença de vertigem concomitante à paralisia e resposta acima de 3,5 mm no teste de Hilger estiveram relacionados com mau prognóstico. Por outro lado, a ausência de sintomas concomitantes, a diminuição do lacrimejamento e o início súbito foram relacionados com bom prognóstico. CONCLUSÃO: A análise de fatores clínicos, associada ao teste de Hilger, pode indicar o prognóstico da paralisia facial com reduzida margem de erro, sendo uma alternativa bastante interessante especialmente quando não há disponibilidade da ENoG.

Fratura de mandíbula: análise de 293 pacientes tratados no Hospital de Clínicas da Universidade Federal de Uberlândia

A fratura de mandíbula ocupa o segundo lugar entre as fraturas dos ossos da face, tendo havido aumento significativo de casos nos últimos anos. A não-identificação e o tratamento inadequado podem levar à deformidade estética ou funcional permanente. OBJETIVO: Avaliar os casos submetidos à redução de fratura de mandíbula no Hospital de Clínicas da Universidade Federal de Uberlândia, entre janeiro de 1974 e dezembro de 2002. FORMA DE ESTUDO: coorte historica. PACIENTES E MÉTODO: Duzentos e noventa e três pacientes foram submetidos à redução de fratura de mandíbula e retrospectivamente foram avaliados segundo fatores relacionados a: paciente, trauma, quadro clínico e tratamento cirúrgico. RESULTADOS: Houve uma clara tendência de aumento do número de fraturas de mandíbula ao longo dos anos. Houve um predomínio no sexo masculino (4:1), com pico de ocorrência entre 20 a 29 anos. As principais causas de fratura da mandíbula neste estudo foram acidentes de trânsito e violência, perfazendo juntas 72,4%. Cento e trinta e cinco pacientes apresentavam fratura única. Os sítios mais acometidos foram, em ordem decrescente, sínfise, côndilo, ângulo, corpo, ramo e processo coronóide. Foram realizadas redução incruenta (28), cruenta (213) e associação das duas (11 pacientes), sendo que 56,8% dos pacientes foram tratados nos primeiros 3 dias e 50,4% recebeu a alta hospitalar até o primeiro pós-operatório. Cerca de 10% dos pacientes apresentaram complicações, sendo osteomielite a mais freqüente. CONCLUSÃO: A incidência de fraturas de mandíbula foi marcadamente maior no sexo masculino, durante a terceira década de vida. A causa mais comum foi o acidente de trânsito e as regiões mais atingidas foram sínfise e côndilo. As fraturas isoladas de mandíbula ocorreram em mais de metade dos casos. A maioria dos pacientes foi tratada nos primeiros três dias e recebeu alta até o primeiro pós-operatório. A redução cruenta foi tratamento mais comumente empregado. A complicação mais freqüente foi a osteomielite.