1,755 research outputs found

    Raman threshold for nth-order cascade Raman amplification

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    We study theoretically and experimentally Raman threshold for 1, 2, ... , n orders Stokes in a free running configuration. Using alternative way to solve the differential coupled equations that describe the stimulate Raman scattering, we find simple mathematical expressions that allow calculating the necessary pumping power to obtain Raman threshold for nth-order Stokes and the maximum output power available in each Stokes. The theoretical calculations coincide with the results obtained experimentally

    Detection of Pathogenic Leptospires in Water and Soil in Areas Endemic to Leptospirosis in Nicaragua

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    In Nicaragua, there are ideal environmental conditions for leptospirosis. The objective of this investigation was to detect pathogenic and saprophytic leptospires in water and soil samples from leptospirosis-endemic areas in Nicaragua. Seventy-eight water and 42 soil samples were collected from houses and rivers close to confirmed human cases.Leptospiraspp was isolated in Ellinghausen-McCullough-Johnson-Harris (EMJH) culture medium with 5-fluororacil and positive samples were analyzed through PCR for theLipL32gene, specific for pathogenic leptospires (P1 clade). There were 73 positive cultures from 120 samples, however only six of these (5% of all collected samples) were confirmed to be pathogenic, based on the presence of theLipL32gene (P1 clade). Of these six pathogenic isolates, four were from Leon and two from Chinandega. Four pathogenic isolates were obtained from water and two from soil. This study proved the contamination of water and soil with pathogenic leptospires, which represents a potential risk for public health

    Practical guidelines for the early diagnosis of Sjogren's syndrome in primary healthcare

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    Primary care physicians can play a crucial role by recognising Sjogren's syndrome (SS) in the early stages identifying those patients with the greatest probability of being diagnosed with SS. SS has a very specific epidemiological profile at presentation (female aged 3050 years), which may aid an early diagnosis. Although the disease may be expressed in many guises, there are three predominant clinical presentations that should be considered as key clues to increased clinical suspicion (multiple symptoms of dryness, asthenia-polyalgia syndrome and systemic organ-specific manifestations). The physical examination may provide important clues to systemic involvement (parotid gland enlargement, skin lesions suggestive of purpura or annular erythema, respiratory crackles, arthritis, neurological sensory or motor deficits). Simple laboratory studies may be very useful in reinforcing the clinical suspicion of SS, and the triad of cytopenia, raised erythrocyte sedimentation rate and high serum gamma globulin levels is a very specific "biological" pattern suggesting SS. A solid clinical suspicion of SS requires both the patient reporting sicca symptoms and objective evidence that these symptoms are associated with dysfunction of the lachrymal and salivary glands. Ultrasonography of the parotid glands, a non-invasive method, may be a major advance in the diagnostic approach to SS in primary care. Primary care physicians must be considered essential members of the multidisciplinary team in charge of the follow-up of SS patients, due to their key role in the continuum of patient care and their cross-sectional knowledge of common diseases that frequently coexist in patients with SS.</p

    Application of Air Micronanobubbles to Reduce Arsenic Present in an Effluent Generated at the Laboratory Level

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    The objective of this research was applying air Micronanobubbles to reduce Arsenic present in an effluent generated at the laboratory level. In this research, an effluent with arsenic metal was used from a mixture of minerals with the presence of arsenopyrite with 19% As content. This mixture of minerals was stirred in a hot alkaline leaching medium at a temperature of 80 Ā°C, with Na2S (1.5 M) and NaOH (1.0 M), then it was diluted with distilled water to obtain a volume of 100 L with a concentration of 150 ppm As. This effluent was treated with the air micronanobubble (MNB) generator equipment patented by Dr. Jhonny Valverde Flores. The variables of the pressure and the insufflation time of air as MNB in the effluent with content of the arsenic element were analyzed. A 40% decrease of As was obtained in the effluent. The results indicate that the use of MNB is promising in terms of the reduction of arsenic in solutions with concentrations of the same

    Cribado de Citomegalovirus en mujeres embarazadas

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    Introduction: Cytomegalovirus (CMV) is a DNA virus of the family Herpesviridae, constitutes one of the main causes of congenital infections in the world, the overall prevalence of births in developed countries is 0.64% and the incidence of 1% -7%. The rate of acquisition of CMV in pregnant women is 2% per year, in the medium-high socioeconomic level and 6% at lower levels. The susceptibility is greater in African-American and Hispanic women. The risk ofmaternal-fetal transmission increases with advancing gestational age, also (30-40%) depends on maternal primary infection both seroconversion and in the revival (1-2%), highlighting that the pre-existing maternal immunity not prevent intrauterine transmission or the development of the disease. Objective: To evaluate the frequency of Cytomegalovirus infection in pregnant women. Material and methods: a study of non-experimental, observational -cross in the pro-life basic Hospital, of the city of Latacunga,Ecuador. Analyzed 981 results of screening for IgG and IgM for CMV, pregnant womages between 14 and 45 years who were enrolled in the first trimester of pregnancy, the period between January 1, 2013 to December 31, 2016. Descriptive statistical methods were used. Results: IgG positive was 95.7% and no positive result for IgM. Conclusions: We cannot support universal screening for CMV, by the low prevalence of infection.IntroducciĆ³n: El citomegalovirus(CMV)es un ADN virus, de la familia Herpesviridae, constituye una de las principales causas de infecciones congĆ©nitas en el mundo, la prevalencia general de nacimientos en paĆ­ses desarrollados es de 0,64% y la incidencia del 1% -7%. La tasa de adquisiciĆ³n de CMV en mujeres embarazadas es de 2% anual,en el nivel socioeconĆ³mico medio-alto y 6% en niveles mĆ”s bajos. La susceptibilidad es mayor en mujeres afroamericanas e hispanas. El riesgo de transmisiĆ³n materno-fetalseincrementa con el avance de la edad gestacional, ademĆ”s depende de la seroconversiĆ³n materna tanto en la primoinfecciĆ³n (30-40%) como en la reactivaciĆ³n (1-2%), poniendo en evidencia que la inmunidad materna preexistente no previene la transmisiĆ³n intrauterina o el desarrollo de la enfermedad. Objetivo: Evaluar la frecuencia deinfecciĆ³n por Citomegalovirus en mujeres embarazadas. Material y mĆ©todos: Se realizĆ³ un estudio no experimental, observacional ā€“transversal en el Hospital BĆ”sico PROVIDA, de la cuidad de Latacunga, Ecuador. Se analizaron 981 resultados de screening de IgG e IgM para CMV, de mujeres gestantes en edades entre 14 y 45 aƱos que cursaban el primer trimestre de embarazo, del periodo comprendido entre el 1 de enero de 2013 al 31 de diciembre de 2016.Se utilizaron mĆ©todos estadĆ­sticos descriptivos. Resultados: La IgG fue positiva el 95,7% y ningĆŗn resultado positivo para IgM. Conclusiones: No podemos apoyar el cribado universal de CMV, por la baja prevalencia de primoinfeccion

    Cribado de Citomegalovirus en mujeres embarazadas

    Get PDF
    Introduction: Cytomegalovirus (CMV) is a DNA virus of the family Herpesviridae, constitutes one of the main causes of congenital infections in the world, the overall prevalence of births in developed countries is 0.64% and the incidence of 1% -7%. The rate of acquisition of CMV in pregnant women is 2% per year, in the medium-high socioeconomic level and 6% at lower levels. The susceptibility is greater in African-American and Hispanic women. The risk ofmaternal-fetal transmission increases with advancing gestational age, also (30-40%) depends on maternal primary infection both seroconversion and in the revival (1-2%), highlighting that the pre-existing maternal immunity not prevent intrauterine transmission or the development of the disease. Objective: To evaluate the frequency of Cytomegalovirus infection in pregnant women. Material and methods: a study of non-experimental, observational -cross in the pro-life basic Hospital, of the city of Latacunga,Ecuador. Analyzed 981 results of screening for IgG and IgM for CMV, pregnant womages between 14 and 45 years who were enrolled in the first trimester of pregnancy, the period between January 1, 2013 to December 31, 2016. Descriptive statistical methods were used. Results: IgG positive was 95.7% and no positive result for IgM. Conclusions: We cannot support universal screening for CMV, by the low prevalence of infection.IntroducciĆ³n: El citomegalovirus(CMV)es un ADN virus, de la familia Herpesviridae, constituye una de las principales causas de infecciones congĆ©nitas en el mundo, la prevalencia general de nacimientos en paĆ­ses desarrollados es de 0,64% y la incidencia del 1% -7%. La tasa de adquisiciĆ³n de CMV en mujeres embarazadas es de 2% anual,en el nivel socioeconĆ³mico medio-alto y 6% en niveles mĆ”s bajos. La susceptibilidad es mayor en mujeres afroamericanas e hispanas. El riesgo de transmisiĆ³n materno-fetalseincrementa con el avance de la edad gestacional, ademĆ”s depende de la seroconversiĆ³n materna tanto en la primoinfecciĆ³n (30-40%) como en la reactivaciĆ³n (1-2%), poniendo en evidencia que la inmunidad materna preexistente no previene la transmisiĆ³n intrauterina o el desarrollo de la enfermedad. Objetivo: Evaluar la frecuencia deinfecciĆ³n por Citomegalovirus en mujeres embarazadas. Material y mĆ©todos: Se realizĆ³ un estudio no experimental, observacional ā€“transversal en el Hospital BĆ”sico PROVIDA, de la cuidad de Latacunga, Ecuador. Se analizaron 981 resultados de screening de IgG e IgM para CMV, de mujeres gestantes en edades entre 14 y 45 aƱos que cursaban el primer trimestre de embarazo, del periodo comprendido entre el 1 de enero de 2013 al 31 de diciembre de 2016.Se utilizaron mĆ©todos estadĆ­sticos descriptivos. Resultados: La IgG fue positiva el 95,7% y ningĆŗn resultado positivo para IgM. Conclusiones: No podemos apoyar el cribado universal de CMV, por la baja prevalencia de primoinfeccion

    Search for squarks and gluinos in events with isolated leptons, jets and missing transverse momentum at sāˆš=8 TeV with the ATLAS detector

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    The results of a search for supersymmetry in final states containing at least one isolated lepton (electron or muon), jets and large missing transverse momentum with the ATLAS detector at the Large Hadron Collider are reported. The search is based on proton-proton collision data at a centre-of-mass energy sāˆš=8 TeV collected in 2012, corresponding to an integrated luminosity of 20 fbāˆ’1. No significant excess above the Standard Model expectation is observed. Limits are set on supersymmetric particle masses for various supersymmetric models. Depending on the model, the search excludes gluino masses up to 1.32 TeV and squark masses up to 840 GeV. Limits are also set on the parameters of a minimal universal extra dimension model, excluding a compactification radius of 1/R c = 950 GeV for a cut-off scale times radius (Ī›R c) of approximately 30

    Single hadron response measurement and calorimeter jet energy scale uncertainty with the ATLAS detector at the LHC

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    The uncertainty on the calorimeter energy response to jets of particles is derived for the ATLAS experiment at the Large Hadron Collider (LHC). First, the calorimeter response to single isolated charged hadrons is measured and compared to the Monte Carlo simulation using proton-proton collisions at centre-of-mass energies of sqrt(s) = 900 GeV and 7 TeV collected during 2009 and 2010. Then, using the decay of K_s and Lambda particles, the calorimeter response to specific types of particles (positively and negatively charged pions, protons, and anti-protons) is measured and compared to the Monte Carlo predictions. Finally, the jet energy scale uncertainty is determined by propagating the response uncertainty for single charged and neutral particles to jets. The response uncertainty is 2-5% for central isolated hadrons and 1-3% for the final calorimeter jet energy scale.Comment: 24 pages plus author list (36 pages total), 23 figures, 1 table, submitted to European Physical Journal

    Measurements of fiducial and differential cross sections for Higgs boson production in the diphoton decay channel at sāˆš=8 TeV with ATLAS

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    Measurements of fiducial and differential cross sections are presented for Higgs boson production in proton-proton collisions at a centre-of-mass energy of sāˆš=8 TeV. The analysis is performed in the H ā†’ Ī³Ī³ decay channel using 20.3 fbāˆ’1 of data recorded by the ATLAS experiment at the CERN Large Hadron Collider. The signal is extracted using a fit to the diphoton invariant mass spectrum assuming that the width of the resonance is much smaller than the experimental resolution. The signal yields are corrected for the effects of detector inefficiency and resolution. The pp ā†’ H ā†’ Ī³Ī³ fiducial cross section is measured to be 43.2 Ā±9.4(stat.) āˆ’ā€‰2.9 +ā€‰3.2 (syst.) Ā±1.2(lumi)fb for a Higgs boson of mass 125.4GeV decaying to two isolated photons that have transverse momentum greater than 35% and 25% of the diphoton invariant mass and each with absolute pseudorapidity less than 2.37. Four additional fiducial cross sections and two cross-section limits are presented in phase space regions that test the theoretical modelling of different Higgs boson production mechanisms, or are sensitive to physics beyond the Standard Model. Differential cross sections are also presented, as a function of variables related to the diphoton kinematics and the jet activity produced in the Higgs boson events. The observed spectra are statistically limited but broadly in line with the theoretical expectations
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