Ballistic Josephson junctions in edge-contacted graphene

Hybrid graphene-superconductor devices have attracted much attention since the early days of graphene research. So far, these studies have been limited to the case of diffusive transport through graphene with poorly defined and modest quality graphene-superconductor interfaces, usually combined with small critical magnetic fields of the superconducting electrodes. Here we report graphene based Josephson junctions with one-dimensional edge contacts of Molybdenum Rhenium. The contacts exhibit a well defined, transparent interface to the graphene, have a critical magnetic field of 8 Tesla at 4 Kelvin and the graphene has a high quality due to its encapsulation in hexagonal boron nitride. This allows us to study and exploit graphene Josephson junctions in a new regime, characterized by ballistic transport. We find that the critical current oscillates with the carrier density due to phase coherent interference of the electrons and holes that carry the supercurrent caused by the formation of a Fabry-P\'{e}rot cavity. Furthermore, relatively large supercurrents are observed over unprecedented long distances of up to 1.5 $\mu$m. Finally, in the quantum Hall regime we observe broken symmetry states while the contacts remain superconducting. These achievements open up new avenues to exploit the Dirac nature of graphene in interaction with the superconducting state.Comment: Updated version after peer review. Includes supplementary material and ancillary file with source code for tight binding simulation

Immunological Basis for the Gender Differences in Murine Paracoccidioides brasiliensis Infection

This study aimed to investigate the immunological mechanisms involved in the gender distinct incidence of paracoccidioidomycosis (pcm), an endemic systemic mycosis in Latin America, which is at least 10 times more frequent in men than in women. Then, we compared the immune response of male and female mice to Paracoccidioides brasiliensis infection, as well as the influence in the gender differences exerted by paracoccin, a P. brasiliensis component with carbohydrate recognition property. High production of Th1 cytokines and T-bet expression have been detected in the paracoccin stimulated cultures of spleen cells from infected female mice. In contrast, in similar experimental conditions, cells from infected males produced higher levels of the Th2 cytokines and expressed GATA-3. Macrophages from male and female mice when stimulated with paracoccin displayed similar phagocytic capability, while fungicidal activity was two times more efficiently performed by macrophages from female mice, a fact that was associated with 50% higher levels of nitric oxide production. In order to evaluate the role of sexual hormones in the observed gender distinction, we have utilized mice that have been submitted to gonadectomy followed by inverse hormonal reconstitution. Spleen cells derived from castrated males reconstituted with estradiol have produced higher levels of IFN-γ (1291±15 pg/mL) and lower levels of IL-10 (494±38 pg/mL), than normal male in response to paracoccin stimulus. In contrast, spleen cells from castrated female mice that had been treated with testosterone produced more IL-10 (1284±36 pg/mL) and less IFN-γ (587±14 pg/mL) than cells from normal female. In conclusion, our results reveal that the sexual hormones had a profound effect on the biology of immune cells, and estradiol favours protective responses to P. brasiliensis infection. In addition, fungal components, such as paracoccin, may provide additional support to the gender dimorphic immunity that marks P. brasiliensis infection

Pulmonary paracoccidoidomycosis: radiology and clinical-epidemiological evaluation Paracoccidioidomicose pulmonar: radiologia e avaliação clínico-epidemiológica

INTRODUCTION: The purpose of this study was to compare respiratory signs and symptoms between patients with and without chest X-ray abnormalities in order to establish the meaning of radiographic findings in pulmonary PCM diagnosis. METHODS: The epidemiological, clinical and radiological lung findings of 44 patients with paracoccidiodomycosis (PCM) were evaluated. Patients were divided into two groups of 23 and 21 individuals according to the presence (group 1) or absence (group 2) of chest X-ray abnormalities, respectively, and their clinical data was analyzed with the aid of statistical tools. RESULTS: As a general rule, patients were rural workers, young adult males and smokers - group 1 and 2, respectively: males (91.3% and 66.7%); mean age (44.4 and 27.9 year-old); smoking (34.7% and 71.4 %); acute/subacute presentation (38.1% and 21.7%); chronic presentation (61.9% and 78.3%). The most frequent respiratory manifestations were - group 1 and 2, respectively: cough (25% and 11.4%) and dyspnea (22.7% and 6.8%). No statistical difference was observed in pulmonary signs and symptoms between patients with or without radiographic abnormalities. The most frequent radiological finding was nodular (23.8%) or nodular-fibrous (19%), bilateral (90.5%) and diffuse infiltrates (85.7%). CONCLUSIONS: Absence of statistical difference in pulmonary signs and symptoms between these two groups of patients with PCM indicates clinical-radiological dissociation. A simplified classification of radiological lung PCM findings is suggested, based on correlation of these data and current literature review.<br>INTRODUÇÃO: Comparar sinais e sintomas respiratórios entre pacientes com e sem alterações à radiografia de tórax para se estabelecer o significado dos achados radiográficos no diagnóstico da paracoccidioidomicose pulmonar. MÉTODOS: Os achados epidemiológicos, clínicos e radiológicos de 44 pacientes com paracoccidioidomicose (PCM) foram avaliados. Os pacientes foram divididos em dois grupos de 23 e 21 indivíduos de acordo com a presença (grupo 1) ou ausência (grupo 2) de anormalidades à radiografia de tórax, respectivamente, e seus dados clínicos foram analisados com auxílio de ferramentas estatísticas. RESULTADOS: Como regra geral, os pacientes eram trabalhadores rurais do sexo masculino, tabagistas e em idade adulta jovem - grupo 1 e 2, respectivamente: homens (91,3% e 66,7%); média de idade (44,4 e 27,9 anos); tabagismo (34,7% e 71,4 %); forma aguda/subaguda (38,1% e 21,7%); forma crônica (61,9% e 78,3%). As manifestações respiratórias mais frequentes foram - grupo 1 e 2, respectivamente: tosse (25% e 11,4%) e dispnéia (22,7% e 6,8%). Nenhuma diferença estatística foi observada nos sinais e sintomas respiratórios entre pacientes com ou sem anormalidades radiográficas. Os achados radiológicos mais frequentes foram o padrão nodular (23,8%) ou nodular-fibrótico (19%), bilateral (90,5%) e infiltrado difuso (85,7%). CONCLUSÕES: A ausência de diferença estatística nos sinais e sintomas pulmonares entre estes dois grupos de pacientes com PCM sugere dissociação clínico-radiológica. Uma classificação simplificada dos achados radiológicos pulmonares da PCM é sugerida, com base na correlação destes dados e revisão da literatura atual