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Single photon sources (SPS) based on semiconductor quantum dot (QD) platforms are restricted to low temperature (T) operation due to the presence of strong dephasing processes. Although the integration of QD in optical cavities provides an enhancement of its emission properties, the technical requirements for maintaining high indistinguishability (I) at high T are still beyond the state of the art. Recently, new theoretical approaches have shown promising results by implementing two-dipole-coupled-emitter systems. Here, we propose a platform based on an optimized five-dipole-coupled-emitter system coupled to a cavity which enables perfect I at high T. Within our scheme the realization of perfect I single photon emission with dissipative QDs is possible using well established photonic platforms. For the optimization procedure we have developed a novel machine-learning approach which provides a significant computational-time reduction for high demanding optimization algorithms. Our strategy opens up interesting possibilities for the optimization of different photonic structures for quantum information applications, such as the reduction of quantum decoherence in clusters of coupled two-level quantum systems.

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Staying in control of delicate processes in the evermore emerging field of micro, nano and quantum-technologies requires suitable devices to measure temperature and temperature flows with high thermal and spatial resolution. In this work, we design optical microring resonators (ORRs) made of different materials (silicon, diamond and gallium nitride) and simulate their temperature behavior using several finite-element methods. We predict the resonance frequencies of the designed devices and their temperature-induced shift (16.8 pm K-1 for diamond, 68.2 pm K-1 for silicon and 30.4 pm K-1 for GaN). In addition, the influence of two-photon-absorption (TPA) and the associated self-heating on the accuracy of the temperature measurement is analysed. The results show that owing to the absence of intrinsic TPA-processes self-heating at resonance is less critical in diamond and GaN than in silicon, with the threshold intensity I th = α / ß , α and ß being the linear and quadratic absorption coefficients, respectively.

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BACKGROUND: A large and unsuspected tuberculosis outbreak involving 18.7% of the total of the tuberculosis cases studied, was detected in a population-based molecular epidemiological study performed in Zaragoza (Spain) from 2001 to 2004. METHODS: The Mycobacterium tuberculosis drug-susceptible strain, named MTZ strain, was genetically characterized by IS6110-RFLP, Spoligotyping and by MIRU-VNTR typing and the genetic patterns obtained were compared with those included in international databases. The characteristics of the affected patients, in an attempt to understand why the MTZ strain was so highly transmitted among the population were also analyzed. RESULTS: The genetic profile of the MTZ strain was rare and not widely distributed in our area or elsewhere. The patients affected did not show any notable risk factor for TB. CONCLUSION: The M. tuberculosis strain MTZ, might have particular transmissibility or virulence properties, and we believe that greater focus should be placed on stopping its widespread dissemination.

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OBJECTIVES: To describe non-meningococcal bacterial meningitis (nMM) and to evaluate the Epidemiological Surveillance System (ESS) in the province of Saragossa (Spain) between 1999 and 2004. METHODS: Information was obtained from the register of diseases subject to mandatory reporting and the Minimum Basic Data Set (MBDS). The ESS was evaluated by using the Centers for Disease Control and Prevention (CDC) criteria and by estimating the completeness of the system through the capture-recapture technique. RESULTS: 111 cases of nMM were notified (62.2% in males) and the mean age was 40.7 years. The largest proportion of cases (16.5%) occurred in children under 2 years of age. The clinical presentation was meningitis in 81.1%. Diagnosis was through bacterial culture in 70.3%. Streptococcus sp. was found in 54% (82% due to S. pneumoniae), enterobacteria in 5.4%, Listeria and Staphylococcus in 4.5%, Pseudomonas aeruginosa in 1.8%, and Haemophilus influenzae in 0.9%. The incidence rate per 100,000 inhabitants was 1.6 in 2004 and 2.6 in 2001. The case fatality was 7.3%. The completeness of the mandatory reporting system reached a peak in 2004 at 84.4%. The combined completeness of the MBDS and the mandatory reporting system was above 85% and timeliness of reporting was 2 days. The acceptability of the system was high since 75% of all variables were complete in 97% of the questionnaires. CONCLUSION: We highlight the importance of evaluation of the ESS, based on its results. nMM due to S. pneumoniae represent an important group of diseases and their case fatality is high. The completeness of the ESS in Saragossa was over 80% when the mandatory reporting system and the MBDS were combined. Incorporating the MBDS into surveillance would facilitate the estimation of the real incidence of various diseases subject to mandatory reporting.

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Objetivos: Describir las meningitis no meningocócicas bacterianas (MnMB) y evaluar el Sistema de Vigilancia Epidemiológica (SVE) en la provincia de Zaragoza entre 1999 y 2004. Métodos: Se utilizó el registro de enfermedades de declaración obligatoria (EDO) y el conjunto mínimo básico de datos (CMBD). Se evaluó el SVE utilizando criterios de los Centers for Disease Control and Prevention, estimando la exhaustividad mediante captura-recaptura. Resultados: Se notificaron 111 casos de MnMB (62,2% en hombres). La edad media fue de 40,7 años. La mayor proporción de casos (16,5%) fue en niños menores de 2 años. La forma clínica en el 81,1% de los casos fue la meningitis; el 70,3% fue diagnosticada por cultivo. Aparecieron Streptococcus en el 54% de los casos (el 82% por S. pneumoniae), enterobacterias en el 5,4%, Lysteria y Staphylococcus en el 4,5%, Pseudomona aeruginosa en el 1,8%, y Haemophilus influenzae en el 0,9%. La incidencia por 100.000 habitantes fue entre 1,6 en 2004 y 2,6 en 2001. La letalidad fue del 7,3%. La exhaustividad del sistema EDO fue máxima en el año 2001 (del 84,4%). La exhaustividad conjunta con CMBD fue superior al 85% y la oportunidad fue de 2 días. La aceptabilidad del sistema fue buena, ya que el 75% de las variables estaban cumplimentadas en el 97% de las encuestas. Conclusiones: Se destaca la relevancia de la evaluación del SVE en función de sus resultados. Las MnMB debidas a S. pneumoniae representan un grupo significativo y su letalidad es elevada. La exhaustividad del SVE en Zaragoza supera el 80%, al considerar EDO y CMBD. La incorporación del CMBD en la vigilancia facilitaría una aproximación a la incidencia real de algunas EDO

Objectives: To describe non-meningococcal bacterial meningitis (nMM) and to evaluate the Epidemiological Surveillance System (ESS) in the province of Saragossa (Spain) between 1999 and 2004. Methods: Information was obtained from the register of diseases subject to mandatory reporting and the Minimum Basic Data Set (MBDS). The ESS was evaluated by using the Centers for Disease Control and Prevention (CDC) criteria and by estimating the completeness of the system through the capture-recapture technique. Results: 111 cases of nMM were notified (62.2% in males) and the mean age was 40.7 years. The largest proportion of cases (16.5%) occurred in children under 2 years of age. The clinical presentation was meningitis in 81.1%. Diagnosis was through bacterial culture in 70.3%. Streptococcus sp. was found in 54% (82% due to S. pneumoniae), enterobacteria in 5.4%, Listeria and Staphylococcus in 4.5%, Pseudomonas aeruginosa in 1.8%, and Haemophilus influenzae in 0.9%. The incidence rate per 100,000 inhabitants was 1.6 in 2004 and 2.6 in 2001. The case fatality was 7.3%. The completeness of the mandatory reporting system reached a peak in 2004 at 84.4%. The combined completeness of the MBDS and the mandatory reporting system was above 85% and timeliness of reporting was 2 days. The acceptability of the system was high since 75% of all variables were complete in 97% of the questionnaires. Conclusion: We highlight the importance of evaluation of the ESS, based on its results. nMM due to S. pneumoniae represent an important group of diseases and their case fatality is high. The completeness of the ESS in Saragossa was over 80% when the mandatory reporting system and the MBDS were combined. Incorporating the MBDS into surveillance would facilitate the estimation of the real incidence of various diseases subject to mandatory reporting

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BACKGROUND AND OBJECTIVE: On the basis of several cases of cryptosporidiosis detected in a child day-care center, we stablished the extent of the outbreak and investigated causes of parasite transmission. PATIENTS AND METHOD: A retrospective cohort study was designed on all children attending day-care center and care givers to determine their infection status and identify risk factors associated to the outbreak. RESULTS: 24 cases of cryptosporidiosis were detected, with an attack rate of 0.46 (24/52); 12 of them were parasitologycally confirmed. All care givers were negative for Cryptosporidium and none of them reported symptoms of acute gastroenteritis. Transmission pattern was compatible with person to person modes. Among the factors investigated, two were associated with the risk of disease: diaper wear (relative risk = 2.06; p = 0.059); and diarrhea in relatives (relative risk = 2.05; p = 0.01). In all confirmed cases, Cryptosporidium hominis (previously known as C. parvum, genotype 1), was identified. CONCLUSIONS: Cryptosporidiosis should be considered as a possible cause of outbreaks of gastroenteritis at day-care centers. Increasing care on diaper changing practices, specially over children with diarrhea, may be the key factor to prevent transmission of Cryptosporidium.

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Fundamento y objetivo: Ante la aparición de varios casos de criptosporidiosis en niños de una guardería, se estudió la extensión del brote y las causas de transmisión del parásito. Pacientes y método: Se diseñó un estudio de cohortes retrospectivo en el que se incluyó a todos los niños que asistían a la guardería en ese momento y a las cuidadoras, para determinar su estado de parasitación e identificar los factores de riesgo asociados al brote. Resultados: Durante el período de estudio se detectaron 24 casos de criptosporidiosis, 12 de ellos confirmados parasitológicamente, con una tasa de ataque de 0,46 (24/52). Ninguna de las cuidadoras presentó síntomas ni fue positiva al parásito. La transmisión de la infección presentó un patrón indicativo de mecanismos de persona a persona. Dentro de los factores de riesgo estudiados, los 2 únicos que pudieron relacionarse con la enfermedad fueron el uso de pañal (riesgo relativo = 2,06; p = 0,059) y la diarrea en familiares (riesgo relativo = 2,05; p = 0,01). La especie encontrada en los casos confirmados fue Cryptosporidium hominis (antes conocido como C. parvum, genotipo 1). Conclusiones: La criptosporidiosis debería contemplarse como posible causa de brotes de gastroenteritis en guarderías. Aumentar las precauciones higiénicas en las maniobras de cambio de pañal, especialmente en niños con diarrea, parece determinante para evitar la transmisión de Cryptosporidium

Background and objective: On the basis of several cases of cryptosporidiosis detected in a child day-care center, we stablished the extent of the outbreak and investigated causes of parasite transmission. Patients and method: A retrospective cohort study was designed on all children attending day-care center and care givers to determine their infection status and identify risk factors associated to the outbreak. Results: 24 cases of cryptosporidiosis were detected, with an attack rate of 0.46 (24/52); 12 of them were parasitologycally confirmed. All care givers were negative for Cryptosporidium and none of them reported symptoms of acute gastroenteritis. Transmission pattern was compatible with person to person modes. Among the factors investigated, two were associated with the risk of disease: diaper wear (relative risk = 2.06; p = 0.059); and diarrhea in relatives (relative risk = 2.05; p = 0.01). In all confirmed cases, Cryptosporidium hominis (previously known as C. parvum, genotype 1), was identified. Conclusions: Cryptosporidiosis should be considered as a possible cause of outbreaks of gastroenteritis at day-care centers. Increasing care on diaper changing practices, specially over children with diarrhea, may be the key factor to prevent transmission of Cryptosporidium

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