The paper considers the consensus problem in large networks represented by time-varying directed graphs. A practical way of dealing with large-scale networks is to reduce their dimension by collapsing the states of nodes belonging to densely and intensively connected clusters into aggregate variables. It will be shown that under suitable conditions, the states of the agents in each cluster converge fast toward a local agreement. Local agreements correspond to aggregate variables which slowly converge to consensus. Existing results concerning the time-scale separation in large networks focus on fixed and undirected graphs. The aim of this work is to extend these results to the more general case of time-varying directed topologies. It is noteworthy that in the fixed and undirected graph case the average of the states in each cluster is time-invariant when neglecting the interactions between clusters. Therefore, they are good candidates for the aggregate variables. This is no longer possible here. Instead, we find suitable time-varying weights to compute the aggregate variables as time-invariant weighted averages of the states in each cluster. This allows to deal with the more challenging time-varying directed graph case. We end up with a singularly perturbed system which is analyzed by using the tools of two time-scales averaging which seem appropriate to this system.

BackgroundSince the emergence of social media in 2004, a growing percentage of patients use this technology for health related reasons. To reflect on the alleged beneficial and potentially harmful effects of social media use by patients, the aim of this paper is to provide an overview of the extant literature on the effects of social media use for health related reasons on patients and their relationship with healthcare professionals.MethodsWe conducted a systematic literature review on empirical research regarding the effects of social media use by patients for health related reasons. The papers we included met the following selection criteria: (1) published in a peer-reviewed journal, (2) written in English, (3) full text available to the researcher, (4) contain primary empirical data, (5) the users of social media are patients, (6) the effects of patients using social media are clearly stated, (7) satisfy established quality criteria.ResultsInitially, a total of 1,743 articles were identified from which 22 were included in the study. From these articles six categories of patients’ use of social media were identified, namely: emotional, information, esteem, network support, social comparison and emotional expression. The types of use were found to lead to seven identified types of effects on patients, namely improved self-management and control, enhanced psychological well-being, and enhanced subjective well-being, diminished subjective well-being, addiction to social media, loss of privacy, and being targeted for promotion. Social media use by patients was found to affect the healthcare professional and patient relationship, by leading to more equal communication between the patient and healthcare professional, increased switching of doctors, harmonious relationships, and suboptimal interaction between the patient and healthcare professional.ConclusionsOur review provides insights into the emerging utilization of social media in healthcare. In particular, it identifies types of use by patients as well as the effects of such use, which may differ between patients and doctors. Accordingly, our results framework and propositions can serve to guide future research, and they also have practical implications for healthcare providers and policy makers.

Resumo A educacao profissional e tecnologica constitui-se em um elemento importante no âmbito do desenvolvimento socioeconomico e produtivo-tecnologico regional a demandar politicas publicas para a educacao basica e de correlatas politicas de fomento a ciencia e tecnologia, devidamente, balizadas por efetivo planejamento participativo e de analise diagnostica da realidade local/nacional. Destaca-se a relevância do processo legislativo na elaboracao/regulamentacao de politicas publicas a requerer o reexame da legislacao federal de ensino. No Brasil, a reforma da legislacao da educacao profissional e tecnologica desenvolveu-se sob a egide da Lei de Diretrizes e Bases da Educacao Nacional no 9.394/96, e posterior legislacao complementar: Decreto Federal 2.208/97, Resolucao do Conselho Nacional de Educacao/Câmara de Educacao Basica (CNE/CEB) no 04/99, e Parecer CNE/CEB no 16/99. A reforma foi marcadamente caracterizada pelo Decreto Federal no 2.208/97 que determinou a dissociacao entre ensino tecnico e medio, de forma a reavivar a historica dicotomia entre: formacao geral/propedeutica e formacao/qualificacao profissional. Tal Decreto foi objetivo de severas criticas, especialmente, pelas ingerencias e distorcoes acarretadas ao principio de integracao/articulacao entre ensino medio e ensino tecnico. Nao obstante, o Decreto Federal no 2.208/97 foi revogado mediante a publicacao do atual Decreto Federal no 5.154/04. Ja em 16 de julho de 2008, ocorre a publicacao da Lei no 11.741 que altera redacao de artigos do capitulo da Educacao Profissional e Tecnologica da LDB no 9394/96. Outrossim, contempla-se a retomada do principio de articulacao/integracao entre ensino medio e ensino tecnico (na modalidade educacao profissional tecnica de nivel medio). Hoje, vivenciamos ‘a reforma da reforma’, e continuamos em busca da construcao de um corpo legislativo solido, coerente e capaz de contemplar a especificidade e, concomitantemente, a demanda pela diversidade de politicas/e organizacoes curriculares correlatas aos diferentes itinerarios formativos a considerar a necessidade de formacao/qualificacao profissional dos sujeitos sociais (jovens e cidadaos trabalhadores) em diferentes faixas etarias na perspectiva da cidadania ativa e de constantes mudancas economicas. Palavras-Chave: politicas publicas, educacao profissional, reforma da legislacao federal de ensino Historical and regulatory policy course path of vocational education technical middle level: the 1996 to 2008 Abstract The vocational and technological education constitutes an important element in the socio-economic and regional productive and technological development to demand public policies for basic education and promotion policies related to science and technology, properly, buoyed by effective participatory planning and diagnostic analysis of local / national reality. The relevance of the legislative process in the development / regulatory policies to apply for a review of federal education legislation Stands out. In Brazil, the reform of vocational education legislation and technology developed under the auspices of the Law of Directives and Bases of National Education No. 9.394 / 96, and further additional legislation: Federal Decree 2.208 / 97, the National Council of Education / Chamber of Basic Education (CNE / CEB) No 04/99, and CNE / CEB No. 16/99. The reform was markedly characterized by Federal Decree No. 2,208 / 97 which determined the dissociation between technical and high school in order to revive the historical dichotomy: general training / exams and training / professional qualification. This decree was goal of severe criticism, especially by interference and distortions brought about the principle of integration / articulation between high school and technical education. Nevertheless, the Federal Decree No. 2,208 / 97 was repealed by publishing the current Federal Decree No. 5,154 / 04. As early as July 16, 2008, is the publication of Law No. 11,741 amending writing articles of chapter of Vocational and Technological Education of LDB No 9394/96. Furthermore, it is contemplated the resumption of the principle of articulation / integration between high school and technical education (vocational education secondary technical mode). Today, we experience 'reform of the reform', and still in search of building a solid legislative body, coherent and able to contemplate the specificity and, concomitantly, the demand for diversity policies / curriculum and related organizations to different training routes to consider the need for training / professional qualification of social subjects (young and citizens workers) in different age groups from the perspective of active citizenship and constant socio-ecnonomicas changes. Keywords: public policy, professional education, reform of federal education legislation

Exposure to aristolochic acid (AA) causes aristolochic acid nephropathy (AAN) and Balkan endemic nephropathy (BEN). Conflicting results have been found for the role of human sulfotransferase 1A1 (SULT1A1) contributing to the metabolic activation of aristolochic acid I (AAI) in vitro. We evaluated the role of human SULT1A1 in AA bioactivation in vivo after treatment of transgenic mice carrying a functional human SULT1A1-SULT1A2 gene cluster (i.e. hSULT1A1/2 mice) and Sult1a1(−/−) mice with AAI and aristolochic acid II (AAII). Both compounds formed characteristic DNA adducts in the intact mouse and in cytosolic incubations in vitro. However, we did not find differences in AAI-/AAII-DNA adduct levels between hSULT1A1/2 and wild-type (WT) mice in all tissues analysed including kidney and liver despite strong enhancement of sulfotransferase activity in both kidney and liver of hSULT1A1/2 mice relative to WT, kidney and liver being major organs involved in AA metabolism. In contrast, DNA adduct formation was strongly increased in hSULT1A1/2 mice compared to WT after treatment with 3-nitrobenzanthrone (3-NBA), another carcinogenic aromatic nitro compound where human SULT1A1/2 is known to contribute to genotoxicity. We found no differences in AAI-/AAII-DNA adduct formation in Sult1a1(−/−) and WT mice in vivo. Using renal and hepatic cytosolic fractions of hSULT1A1/2, Sult1a1(−/−) and WT mice, we investigated AAI-DNA adduct formation in vitro but failed to find a contribution of human SULT1A1/2 or murine Sult1a1 to AAI bioactivation. Our results indicate that sulfo-conjugation catalysed by human SULT1A1 does not play a role in the activation pathways of AAI and AAII in vivo, but is important in 3-NBA bioactivation.

Exposure to aristolochic acid (AA) causes aristolochic acid nephropathy (AAN) and Balkan endemic nephropathy (BEN). Conflicting results have been found for the role of human sulfotransferase 1A1 (SULT1A1) contributing to the metabolic activation of aristolochic acid I (AAI) in vitro. We evaluated the role of human SULT1A1 in AA bioactivation in vivo after treatment of transgenic mice carrying a functional human SULT1A1-SULT1A2 gene cluster (i.e. hSULT1A1/2 mice) and Sult1a1(−/−) mice with AAI and aristolochic acid II (AAII). Both compounds formed characteristic DNA adducts in the intact mouse and in cytosolic incubations in vitro. However, we did not find differences in AAI-/AAII-DNA adduct levels between hSULT1A1/2 and wild-type (WT) mice in all tissues analysed including kidney and liver despite strong enhancement of sulfotransferase activity in both kidney and liver of hSULT1A1/2 mice relative to WT, kidney and liver being major organs involved in AA metabolism. In contrast, DNA adduct formation was strongly increased in hSULT1A1/2 mice compared to WT after treatment with 3-nitrobenzanthrone (3-NBA), another carcinogenic aromatic nitro compound where human SULT1A1/2 is known to contribute to genotoxicity. We found no differences in AAI-/AAII-DNA adduct formation in Sult1a1(−/−) and WT mice in vivo. Using renal and hepatic cytosolic fractions of hSULT1A1/2, Sult1a1(−/−) and WT mice, we investigated AAI-DNA adduct formation in vitro but failed to find a contribution of human SULT1A1/2 or murine Sult1a1 to AAI bioactivation. Our results indicate that sulfo-conjugation catalysed by human SULT1A1 does not play a role in the activation pathways of AAI and AAII in vivo, but is important in 3-NBA bioactivation.

BackgroundThe Comprehensive Headache-related Quality of life Questionnaire (CHQQ), is a recently developed and validated instrument, intended for measuring quality of life of patients with all headache types. Currently no validated headache-specific quality of life questionnaires are available in Serbian. The aim of this study was to translate the CHQQ from Hungarian to Serbian, to make necessary cultural adaptations and to test its psychometric properties in a sample of outpatients with headache.MethodsThe CHQQ was translated and adapted according to internationally accepted guidelines, and then tested on a sample of 216 Serbian headache patients (171 females and 45 males, mean age 42.3 years/SD 13.35; range 18–75). The majority of patients suffered from episodic tension-type headache (TTH); 27 (12.5 %) had episodic migraine. We calculated the internal consistency (Cronbach’s alpha), criterion validity (correlations of individual items, dimensions and whole questionnaire with the clinical characteristics of headache), convergent validity (correlations of the abovementioned scores with results of other instruments measuring headache severity and impact), and discriminative validity (comparison of the scores in the two diagnostic groups) of the CHQQ. We used factor analysis to explore the underlying construct.ResultsThe Serbian translation of CHQQ showed excellent internal consistency, both for the whole instrument (Cronbach’s alpha 0.937) and its dimensions. The validity of the instrument in all aspects (criterion, convergent and discriminative validity) was also excellent when the whole sample and the subgroup of patients with TTH were analyzed, while the results for patients with migraine were less favorable. Factor analysis suggested the existence of a single dimension in this sample.ConclusionsThe Serbian translation of CHQQ is as reliable and valid specific instrument for measuring headache-related quality of life in patients with TTH and probably in patients with migraine.

All resonances, from hydrogen nuclei excited by the high-energy gamma rays in deep space to newly discovered particles produced in Large Hadron Collider, should be described by the same fundamental physical quantities. However, two distinct sets of properties are used to describe resonances: the pole parameters (complex pole position and residue) and the Breit-Wigner parameters (mass, width, and branching fractions). There is an ongoing decades-old debate on which one of them should be abandoned. In this study of nucleon resonances appearing in the elastic pion-nucleon scattering we discover an intricate interplay of the parameters from both sets, and realize that neither set is completely independent or fundamental on its own.