Phase Transitions of Charged Scalars at Finite Temperature and Chemical Potential

We calculate the grand canonical partition function at the one-loop level for scalar quantum electrodynamics at finite temperature and chemical potential. A classical background charge density with a charge opposite that of the scalars ensures the neutrality of the system. For low density systems we find evidence of a first order phase transition. We find upper and lower bounds on the transition temperature below which the charged scalars form a condensate. A first order phase transition may have consequences for helium-core white dwarf stars in which it has been argued that such a condensate of charged helium-4 nuclei could exist.Comment: 20 pages, 3 figures. Version accepted for publication in JHE

b→ssdˉb\to s s \bar d Decay in Two Higgs Doublet Models

In the Standard Model, the box-diagram mediated decay $b\to s s \bar d$ is predicted to occur with an extremely small branching ratio of below $10^{-11}$, thus providing a safe testing ground for exposing new physics. We study this process in several Two Higgs Doublet Models and explore their parameter space, indicating where this process becomes observable.Comment: 10 pages, 3 figure

Composição corporal de crianças e adolescentes diabéticos tipo 1 / Body composition of type 1 diabetic children and adolescentes

Introdução: A diabetes mellitus do tipo 1 (DM1) é a segunda doença crônica mais prevalente na infância,  sua fisiopatologia  envolve alterações metabólicas e glicêmicas que podem predispor ao aumento da massa gorda, diminuição de massa magra e alterações da distribuição de gordura corporal, fatores esses, que potencializam o risco de desenvolver doenças cardiovasculares. Objetivo: Avaliar se os indivíduos com DM1 apresentam alterações no percentual de massa magra, percentual de massa gorda e circunferência abdominal. Métodos: Foram avaliados 48 indivíduos de oito a 17 anos de idade, de ambos os sexos, eutróficos, os quais foram divididos em 2 grupos: diabéticos tipo 1 e o grupo controle (saudáveis). Foram medidos os percentuais de massa magra e massa gorda, através do método de bioimpedância, e a obesidade central, através da medida da circunferência da cintura. Para comparação das variáveis entre os grupos foram realizado o teste de Anova-one-way, Welch ou Kruskal de acordo com o pressuposto de normalidade. Resultados: Indivíduos com DM1 apresentaram maiores índices de massa corporal, percentual de gordura e obesidade central e menor percentual de massa magra que o grupo controle (saudáveis). Conclusão: DM1  apresentam maiores  percentuais de gordura corporal total, maior acúmulo de gordura na região abdominal e menor percentual de massa magra, quando comparados a indivíduos saudáveis. Considerando as  complicações clínicas que essas alterações podem causar, é de fundamental importância a avaliação da composição corporal nessa população

The zinc finger domain of Wilms' tumor 1 suppressor gene (WT1) behaves as a dominant negative, leading to abrogation of WT1 oncogenic potential in breast cancer cells

Abstract Introduction There is growing evidence that the Wilms' tumor 1 suppressor gene (WT1) behaves as an oncogene in some forms of breast cancer. Previous studies have demonstrated that the N-terminal domain of WT1 can act as a dominant negative through self-association. In the studies presented here we have explored the potential for the zinc finger domain (ZF) of WT1 to also have dominant-negative effects, and thus further our understanding of this protein. Methods Using full-length and ZF-only forms of WT1 we assessed their effect on the WT1 and c-myc promoter using luciferase and chromatin immunoprecipitation assays. The gene expression levels were determined by quantitative real-time RT-PCR, northern blot and western blot. We also assessed the effect of the ZF-only form on the growth of breast cancer cell lines in culture. Results Transfection with WT1–ZF plasmids resulted in a stronger inhibition of WT1 promoter than full-length WT1 in breast cancer cells. The WT1–ZF form lacking the lysine–threonine–serine (KTS) insert (ZF - KTS) can bind to the majority of WT1 consensus sites throughout the WT1 promoter region, while the ZF containing the insert (ZF + KTS) form only binds to sites in the proximal promoter. The abundances of endogenous WT1 mRNA and protein were markedly decreased following the stable expression of ZF - KTS in breast cancer cells. The expressions of WT1 target genes, including c-myc, Bcl-2, amphiregulin and TERT, were similarly suppressed by ZF - KTS. Moreover, WT1–ZF - KTS abrogated the transcriptional activation of c-myc mediated by all four predominant isoforms of WT1 (including or lacking alternatively spliced exons 5 and 9). Finally, WT1–ZF - KTS inhibited colony formation and cell division, but induced apoptosis in MCF-7 cells. Conclusion Our observations strongly argue that the WT1–ZF plasmid behaves as a dominant-negative regulator of the endogenous WT1 in breast cancer cells. The inhibition on proliferation of breast cancer cells by WT1–ZF - KTS provides a potential candidate of gene therapy for breast cancer

Clusters of circulating tumor cells traverse capillary-sized vessels

Multicellular aggregates of circulating tumor cells (CTC clusters) are potent initiators of distant organ metastasis. However, it is currently assumed that CTC clusters are too large to pass through narrow vessels to reach these organs. Here, we present evidence that challenges this assumption through the use of microfluidic devices designed to mimic human capillary constrictions and CTC clusters obtained from patient and cancer cell origins. Over 90% of clusters containing up to 20 cells successfully traversed 5- to 10-μm constrictions even in whole blood. Clusters rapidly and reversibly reorganized into single-file chain-like geometries that substantially reduced their hydrodynamic resistances. Xenotransplantation of human CTC clusters into zebrafish showed similar reorganization and transit through capillary-sized vessels in vivo. Preliminary experiments demonstrated that clusters could be disrupted during transit using drugs that affected cellular interaction energies. These findings suggest that CTC clusters may contribute a greater role to tumor dissemination than previously believed and may point to strategies for combating CTC cluster-initiated metastasis

Avaliação agronômica, conservação e qualidade pós-colheita de variedades de alho precoces livres de vírus na região do semiárido piauiense.

Este trabalho teve por objetivo avaliar o desempenho agronômico, conservação e qualidade pós-colheita de bulbos de variedades de alho precoce livres de vírus na região de Picos (PI)

Targeting metabolic activity in high-risk neuroblastoma through Monocarboxylate Transporter 1 (MCT1) inhibition

Amplification of the MYCN oncogene occurs in ~25% of primary neuroblastomas and is the single most powerful biological marker of poor prognosis in this disease. MYCN transcriptionally regulates a range of biological processes important for cancer, including cell metabolism. The MYCN-regulated metabolic gene SLC16A1, encoding the lactate transporter monocarboxylate transporter 1 (MCT1), is a potential therapeutic target. Treatment of neuroblastoma cells with the MCT1 inhibitor SR13800 increased intracellular lactate levels, disrupted the nicotinamide adenine dinucleotide (NADH/NAD+) ratio, and decreased intracellular glutathione levels. Metabolite tracing with 13C-glucose and 13C-glutamine following MCT1 inhibitor treatment revealed increased quantities of tricarboxylic acid (TCA) cycle intermediates and increased oxygen consumption rate. MCT1 inhibition was highly synergistic with vincristine and LDHA inhibition under cell culture conditions, but this combination was ineffective against neuroblastoma xenografts. Posttreatment xenograft tumors had increased synthesis of the MCT1 homolog MCT4/SLC16A, a known resistance factor to MCT1 inhibition. We found that MCT4 was negatively regulated by MYCN in luciferase reporter assays and its synthesis in neuroblastoma cells was increased under hypoxic conditions and following hypoxia-inducible factor (HIF1) induction, suggesting that MCT4 may contribute to resistance to MCT1 inhibitor treatment in hypoxic neuroblastoma tumors. Co-treatment of neuroblastoma cells with inhibitors of MCT1 and LDHA, the enzyme responsible for lactate production, resulted in a large increase in intracellular pyruvate and was highly synergistic in decreasing neuroblastoma cell viability. These results highlight the potential of targeting MCT1 in neuroblastoma in conjunction with strategies that involve disruption of pyruvate homeostasis and indicate possible resistance mechanisms

A Geometric Approach to CP Violation: Applications to the MCPMFV SUSY Model

We analyze the constraints imposed by experimental upper limits on electric dipole moments (EDMs) within the Maximally CP- and Minimally Flavour-Violating (MCPMFV) version of the MSSM. Since the MCPMFV scenario has 6 non-standard CP-violating phases, in addition to the CP-odd QCD vacuum phase \theta_QCD, cancellations may occur among the CP-violating contributions to the three measured EDMs, those of the Thallium, neutron and Mercury, leaving open the possibility of relatively large values of the other CP-violating observables. We develop a novel geometric method that uses the small-phase approximation as a starting point, takes the existing EDM constraints into account, and enables us to find maximal values of other CP-violating observables, such as the EDMs of the Deuteron and muon, the CP-violating asymmetry in b --> s \gamma decay, and the B_s mixing phase. We apply this geometric method to provide upper limits on these observables within specific benchmark supersymmetric scenarios, including extensions that allow for a non-zero \theta_QCD.Comment: 34 pages, 16 eps figures, to appear in JHE

Efeito do Reiki sobre a frequência cardíaca, duplo produto e pressão arterial sistêmica de adolescentes diabéticos / Effect of Reiki on heart rate, dual product and systemic blood pressure in diabetic adolescents

INTRODUÇÃO: A Diabetes Mellitus tipo 1 (DM1) pode levar a alterações do sistema nervoso autônomo. O Reiki reequilibra campos energéticos, favorecendo a homeostase e atuando sobre o controle neural cardíaco. OBJETIVO: Investigar o efeito do Reiki sobre a frequência cardíaca, pressão arterial sistêmica e duplo produto de adolescentes diabéticos. METODOLOGIA: Foram avaliados 15 adolescentes de 12 a 17 anos de idade com diabetes do tipo 1. Foram medidas a frequência cardíaca e a pressão arterial (PA) sistêmica. O duplo produto (DP) foi calculado a partir do produto dessas duas variáveis. Os voluntários foram submetidos a quatro sessões de Reiki e em cada uma delas as medidas anteriores foram repetidas antes e após a sessão. RESULTADOS: PA sistólica diminuiu na 4ª sessão, comparando os valores iniciais e finais (p<0,5) e o DP diminuiu nas sessões um, dois e quatro (p<0,5). Não houve modificação estatística significativa (p>0,5) da FC e PA diastólica.  CONCLUSÃO: Reiki diminuiu a PA sistólica em uma das sessões, isoladamente, e reduziu o duplo produto, que reflete o trabalho do coração, ao analisar a interação entre as quatro sessões

The Hidden Curriculum of Veterinary Education: Mediators and Moderators of Its Effects

The “hidden curriculum” has long been supposed to have an effect on students' learning during their clinical education, and in particular in shaping their ideas of what it means to be a professional. Despite this, there has been little evidence linking specific changes in professional attitudes to the individual components of the hidden curriculum. This study aimed to recognize those components that led to a change in students' professional attitudes at a UK veterinary school, as well as to identify the attitudes most affected. Observations were made of 11 student groups across five clinical rotations, followed by semi-structured interviews with 23 students at the end of their rotation experience. Data were combined and analyzed thematically, taking both an inductive and deductive approach. Views about the importance of technical competence and communication skills were promoted as a result of students' interaction with the hidden curriculum, and tensions were revealed in relation to their attitudes toward compassion and empathy, autonomy and responsibility, and lifestyle ethic. The assessment processes of rotations and the clinical service organization served to communicate the messages of the hidden curriculum, bringing about changes in student professional attitudes, while student-selected role models and the student rotation groups moderated the effects of these influences