Mapping coherence in measurement via full quantum tomography of a hybrid optical detector

Quantum states and measurements exhibit wave-like --- continuous, or particle-like --- discrete, character. Hybrid discrete-continuous photonic systems are key to investigating fundamental quantum phenomena, generating superpositions of macroscopic states, and form essential resources for quantum-enhanced applications, e.g. entanglement distillation and quantum computation, as well as highly efficient optical telecommunications. Realizing the full potential of these hybrid systems requires quantum-optical measurements sensitive to complementary observables such as field quadrature amplitude and photon number. However, a thorough understanding of the practical performance of an optical detector interpolating between these two regions is absent. Here, we report the implementation of full quantum detector tomography, enabling the characterization of the simultaneous wave and photon-number sensitivities of quantum-optical detectors. This yields the largest parametrization to-date in quantum tomography experiments, requiring the development of novel theoretical tools. Our results reveal the role of coherence in quantum measurements and demonstrate the tunability of hybrid quantum-optical detectors.Comment: 7 pages, 3 figure

Low pH immobilizes and kills human leukocytes and prevents transmission of cell-associated HIV in a mouse model

BACKGROUND: Both cell-associated and cell-free HIV virions are present in semen and cervical secretions of HIV-infected individuals. Thus, topical microbicides may need to inactivate both cell-associated and cell-free HIV to prevent sexual transmission of HIV/AIDS. To determine if the mild acidity of the healthy vagina and acid buffering microbicides would prevent transmission by HIV-infected leukocytes, we measured the effect of pH on leukocyte motility, viability and intracellular pH and tested the ability of an acidic buffering microbicide (BufferGel(®)) to prevent the transmission of cell-associated HIV in a HuPBL-SCID mouse model. METHODS: Human lymphocyte, monocyte, and macrophage motilities were measured as a function of time and pH using various acidifying agents. Lymphocyte and macrophage motilities were measured using video microscopy. Monocyte motility was measured using video microscopy and chemotactic chambers. Peripheral blood mononuclear cell (PBMC) viability and intracellular pH were determined as a function of time and pH using fluorescent dyes. HuPBL-SCID mice were pretreated with BufferGel, saline, or a control gel and challenged with HIV-1-infected human PBMCs. RESULTS: Progressive motility was completely abolished in all cell types between pH 5.5 and 6.0. Concomitantly, at and below pH 5.5, the intracellular pH of PBMCs dropped precipitously to match the extracellular medium and did not recover. After acidification with hydrochloric acid to pH 4.5 for 60 min, although completely immotile, 58% of PBMCs excluded ethidium homodimer-1 (dead-cell dye). In contrast, when acidified to this pH with BufferGel, a microbicide designed to maintain vaginal acidity in the presence of semen, only 4% excluded dye at 10 min and none excluded dye after 30 min. BufferGel significantly reduced transmission of HIV-1 in HuPBL-SCID mice (1 of 12 infected) compared to saline (12 of 12 infected) and a control gel (5 of 7 infected). CONCLUSION: These results suggest that physiologic or microbicide-induced acid immobilization and killing of infected white blood cells may be effective in preventing sexual transmission of cell-associated HIV

Keystone symposium: The role of microenvironment in tumor induction and progression, Banff, Canada, 5–10 February 2005

The first Keystone symposium on the role of microenvironment in tumor induction and progression attracted 274 delegates from 13 countries to Banff in the heart of the Canadian Rockies. The meeting was organized by Mina Bissell, Ronald DePinho and Luis Parada, and was held concurrently with the Keystone symposium on cancer and development, chaired by Matthew Scott and Roeland Nusse. The 30 oral presentations and over 130 posters provided an excellent forum for discussing emerging data in this rapidly advancing field

Incidence of uterine post abortion infection at Hospital de Clínicas de Porto Alegre. Is prophylactic antibiotic necessary?

Objetivo: Identificar a incidência de infecção pélvica após aborto espontâneo submetido a esvaziamento uterino num hospital terciário do sul do Brasil e comparar com a literatura internacional. Métodos: Os prontuários eletrônicos do Hospital de Clínicas de Porto Alegre de todas as pacientes que foram submetidas ao esvaziamento uterino por abortamento entre agosto de 2008 e Janeiro de 2012 foram revisados. Foram incluídas no estudo todas as pacientes submetidas à curetagem uterina por abortamento e que tiveram consultas ambulatoriais de revisão após o procedimento. Os dados demográficos e laboratoriais da população estudada, number needed for treatment (NNT) e o number needed to harm (NNH) foram calculados. Resultados: Dos 857 prontuários eletrônicos revistos, 377 pacientes foram submetidas ao esvaziamento uterino por abortamento; 55 casos foram perdidos no seguimento, restando 322 casos que foram classificados como aborto não infectado na admissão. A maioria da população era da raça branca (79%); a prevalência de HIV e VDRL positivos foi de 0,3 e 2%, respectivamente. No seguimento desses 322 casos, num período mínimo de 7 dias, verificou-se que a incidência de infecção pós-procedimento foi de 1,8% (IC95%0,8 a 4). O NNT e o NNH calculado para 42 meses foi de 63 e 39, respectivamente. Conclusão: A incidência de infecção pós-aborto entre agosto de 2008 a janeiro de 2012 foi de 1,8% (0,8 a 4).Objective: To identify the incidence of infection post-uterine evacuation for miscarriage at a tertiary teaching hospital in southern Brazil. Methods: Electronic records of all patients admitted for uterine evacuation for miscarriage between August 2008 and January 2012 were revised. All patients submitted to uterine curettage for miscarriage and had outpatient follow-up were included. Demographic, laboratorial data of the sampled population, the number needed to treat (NNT) and number needed to harm (NNH) were calculated. Results: From 857 reviewed electronic records, 377 underwent uterine evacuation for miscarriage. 55 cases were lost to follow-up, remaining 322 cases classified as non-infected miscarriage at admission. The majority of the population was white (79%); prevalence of positive HIV and VDRL was 0.3 and 2%, respectively. From 322 cases, within a week of follow-up, the incidence of post-miscarriage infection was 1.8% (95%CI 0.8 to 4). In a period of 42 months, the NNT and NNH were 63 and 39, respectively. Conclusion: The incidence of infection after miscarriage between August 2008 and January 2012 was 1.8% (0.8 to 4)