On the computation of the spectral density of two-point functions: complex masses, cut rules and beyond

We present a steepest descent calculation of the Kallen-Lehmann spectral density of two-point functions involving complex conjugate masses in Euclidean space. This problem occurs in studies of (gauge) theories with Gribov-like propagators. As the presence of complex masses and the use of Euclidean space brings the theory outside of the strict validity of the Cutkosky cut rules, we discuss an alternative method based on the Widder inversion operator of the Stieltjes transformation. It turns out that the results coincide with those obtained by naively applying the cut rules. We also point out the potential usefulness of the Stieltjes (inversion) formalism when non-standard propagators are used, in which case cut rules are not available at all.Comment: 16 pages, 4 .pdf figures. v2: version accepted for publication in Physical Review

Vanishing DC holographic conductivity from a magnetic monopole condensate

We show how to obtain a vanishing DC conductivity in 3-dimensional strongly coupled QFT's using a massive 2-form field in the bulk that satisfies a special kind of boundary condition. The real and imaginary parts of the AC conductivity are evaluated in this holographic setup and we show that the DC conductivity identically vanishes even for an arbitrarily small (though nonzero) value of the 2-form mass in the bulk. We identify the bulk action of the massive 2-form with an effective theory describing a phase in which magnetic monopoles have condensed in the bulk. Our results indicate that a condensate of magnetic monopoles in a 4-dimensional bulk leads to a vanishing DC holographic conductivity in 3-dimensional strongly coupled QFT's.Comment: 24 pages, 2 figures, accepted for publication in JHE

BRST invariant formulation of the Bell-CHSH inequality in gauge field theories

A study of the Bell-CHSH inequality in gauge field theories is presented. By using the Kugo-Ojima analysis of the BRST charge cohomology in Fock space, the Bell-CHSH inequality is formulated in a manifestly BRST invariant way. The examples of the free four-dimensional Maxwell theory and the Abelian Higgs model are scrutinized. The inequality is probed by using BRST invariant squeezed states, allowing for large Bell-CHSH inequality violations, close to Tsirelson's bound. An illustrative comparison with the entangled state of two $1/2$ spin particles in Quantum Mechanics is provided.Comment: 12 pages. Revised version. Accepted for publication in SciPost Physic

Interventions for physical activity promotion applied to the primary healthcare settings for people living in regions of low socioeconomic level: study protocol for a non-randomized controlled trial.

BACKGROUND: Regular physical activity practice has been widely recommended for promoting health, but the physical activity levels remain low in the population. Therefore, the study of interventions to promote physical activity is essential. OBJECTIVE: To present the methodology of two physical activity interventions from the "Ambiente Ativo" ("Active Environment") project. METHODS: 12-month non-randomized controlled intervention trial. 157 healthy and physically inactive individuals were selected: health education (n = 54) supervised exercise (n = 54) and control (n = 49). Intervention based on health education: a multidisciplinary team of health professionals organized the intervention in group discussions, phone calls, SMS and educational material. Intervention based on supervised exercise program: consisted of offering an exercise program in groups supervised by physical education professionals involving strength, endurance and flexibility exercises. The physical activity level was assessed by the International Physical Activity Questionnaire (long version), physical activities recalls, pedometers and accelerometers over a seven-day period. RESULT: This study described two different proposals for promoting physical activity that were applied to adults attended through the public healthcare settings. The participants were living in a region of low socioeconomic level, while respecting the characteristics and organization of the system and its professionals, and also adapting the interventions to the realities of the individuals attended. CONCLUSION: Both interventions are applicable in regions of low socioeconomic level, while respecting the social and economic characteristics of each region. TRIAL REGISTRATION: ClinicalTrials.gov NCT01852981

Molecular detection of "Candidatus Mycoplasma haemominutum" in a lion (Panthera leo) from a brazilian zoological garden

Although Mycoplasma haemofelis and "Candidatus Mycoplasma haemominutum" infections have been reported in wild cats from United States, their presence among native and captive wild cats in Brazil is still unknown. A 12 year old healthy male lion (Panthera leo) from the Zoological Garden of Curitiba, Brazil was anesthetized for transportation and dental evaluation. A blood sample was obtained for a complete blood cell count (CBC) and PCR analysis. DNA was extracted and fragments of Mycoplasma haemofelis and "Candidatus Mycoplasma haemominutum" 16S ribosomal RNA gene were amplified in PCR assays. CBC results were within reference intervals. A weak band of 192 pb for "Candidatus Mycoplasma haemominutum" was observed, and no band was amplified from Mycoplasma haemofelis reaction. A weak PCR band associated with normal CBC results and without visible parasitemia or clinical signs may suggest a chronic subclinical infection with "Candidatus Mycoplasma haemominutum". The lack of clinical signs may also represent the low pathogenicity of this organism; however, it is noteworthy that immune suppression caused by management and/or corticoids treatment may induce parasitemia and anemia in this animal. This detection suggests further studies in captive wild cats in Brazilian Zoological Gardens.Embora a infecção por Mycoplasma haemofelis e "Candidatus Mycoplasma haemominutum" tenha sido reportada em felinos selvagens dos Estados Unidos, sua presença entre felinos selvagens de vida livre e de cativeiro no Brasil ainda é desconhecida. Um leão macho, saudável, com 12 anos de idade, residente no Zoológico de Curitiba, Brasil, foi anestesiado para transporte e avaliação dentária. Uma amostra de sangue foi coletada para a realização do hemograma completo e análise pela Reação em Cadeia da Polimerase (PCR). O DNA foi extraído e fragmentos do gene 16SrRNA do Mycoplasma haemofelis e "Candidatus Mycoplasma haemominutum" foram submetidos à metodologia da PCR. O hemograma apresentou valores normais. Uma banda de baixa intensidade de aproximadamente 192 pb do "Candidatus Mycoplasma haemominutum" foi detectada, e nenhuma banda foi observada pela PCR na detecção de Mycoplasma haemofelis. A banda de baixa intensidade, o hemograma normal e a ausência de parasitemia e sinais clínicos podem sugerir uma infecção crônica subclínica por "Candidatus Mycoplasma haemominutum". A ausência de sinais clínicos pode também indicar a baixa patogenicidade desse microrganismo; entretanto, a imunossupressão por manejo e/ou tratamento com corticóides podem levar a parasitemia e conseqüente anemia neste animal. Este achado sugere novos estudos em felinos selvagens de cativeiro em zoológicos brasileiros

Crack-cocaine users have less family cohesion than alcohol users

Objective: Many studies correlate characteristics of family functioning and the development of drug addiction. This study sought to evaluate and compare the family environment styles of two groups of psychoactive substance users: 1) alcohol-only users and 2) crack-cocaine users. Methods: Three hundred and sixty-four users of alcohol, crack-cocaine, and other drugs, recruited from research centers in four Brazilian capitals participated in this study. Subjects were evaluated through the Family Environment Scale and the Addiction Severity Index, 6th version (ASI-6). ASI-6 t-scores were compared by analysis of variance (ANOVA) and post-hoc tests. A final model was obtained using a logistic regression analysis. All analyses were adjusted for partner, age, and psychiatric t-score. Results: We found a significant difference between groups in the cohesion subscale (p = 0.044). The post-hoc test revealed a difference of 1.06 points (95% CI 0.11-2.01) between groups 1 (6.45 +/- 0.28) and 2 (5.38 +/- 0.20). No significant between-group differences were observed in the other subscales. However, categorical analyses of variables regarding family dynamic showed that crack users more often reported that sometimes people in their family hit each other (30.4% vs. 13.2%, p = 0.007) and that people in their family frequently compared each other regarding work and/or school achievement (57.2% vs. 42.6%, p = 0.041). Conclusion: These results suggest that families of crack-cocaine users are less cohesive than families of alcohol users. This type of family environment may affect treatment outcome, and should thus be adequately approached.SENADNational Institutes of Health/National Institute on Drug AbuseUniv Fed Rio do Grande UFRGS, HCPA, CPAD, Porto Alegre, RS, BrazilHCPA, Unidade Bioestat, Porto Alegre, RS, BrazilUniv Fed Rio Grande do Sul, Lab Biossinais Fenomenol & Cognicao, Inst Psicol, Porto Alegre, RS, BrazilUniv Fed Sao Paulo UNIFESP, Dept Psicobiol, Sao Paulo, SP, BrazilUniv Fed Rio de Janeiro UFRJ, Inst Psiquiatria, Rio De Janeiro, RJ, BrazilUniv Fed Sao Paulo UNIFESP, Dept Psicobiol, Sao Paulo, SP, BrazilSENAD: TC 005/2005Web of Scienc