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BACKGROUND: Rates of gonorrhea are increasing across the United States. Understanding and addressing contributing factors associated with longer time to diagnosis and treatment may shorten the duration of infectiousness, which in turn may limit transmission. METHODS: We used Massachusetts data from the US Centers for Disease Control and Prevention Sexually Transmitted Disease Surveillance Network collected between July 2015 and September 2019, along with routinely reported surveillance data, to assess time from gonorrhea symptom onset to presentation to care, and time from presentation to care to receipt of treatment. Factors associated with longer time to presentation (TTP) and time to treatment (TTT) were assessed using Cox proportional hazard models with a constant time variable. RESULTS: Among symptomatic patients (n = 672), 31% did not receive medical care within 7 days of symptom onset. Longer TTP was associated with younger age, female gender, reporting cost as a barrier to care, and provider report of proctitis. Among patients with symptoms and/or known contact to gonorrhea (n = 827), 42% did not receive presumptive treatment. Longer TTT was associated with female gender, non-Hispanic other race/ethnicity, and clinics with less gonorrhea treatment experience. Among asymptomatic patients without known exposure to STI (n = 235), 26% did not receive treatment within 7 days. Longer TTT was associated with sexually transmitted disease clinic/family planning/reproductive health clinics and a test turnaround time of ≥3 days. CONCLUSIONS: Delays in presentation to care and receipt of treatment for gonorrhea are common. Factors associated with longer TTP and TTT highlight multiple opportunities for reducing the infectious period of patients with gonorrhea.
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Infecções por Chlamydia , Gonorreia , Infecções Sexualmente Transmissíveis , Humanos , Feminino , Estados Unidos , Gonorreia/diagnóstico , Gonorreia/tratamento farmacológico , Gonorreia/epidemiologia , Infecções Sexualmente Transmissíveis/epidemiologia , Massachusetts/epidemiologia , Infecções por Chlamydia/epidemiologiaRESUMO
This paper reports on the synthesis and characterization of La2O3:Eu3+ luminescent aerogels fabricated by the sol-gel method and the supercritical drying technique. The % mol concentration of the Eu3+ ion was varied to study the effects on the luminescent properties of the aerogels. XRD and TEM analysis showed that the La2O3:Eu3+ aerogels exhibited a semi-crystalline behavior regardless of whether the concentration of europium was increased. SEM micrographs revealed a porous structure in the aerogels, which were composed of quasi-spherical nanoparticles that were interconnected and formed coral-shaped agglomerates. Photoluminescence spectroscopy characterization showed that the aerogels had an infrared emission located at λ = 793 nm, and the maximum photoluminescence emission intensity was observed for the aerogel with 50% Eu3+. The results demonstrate that, without heat treatment, it is possible to manufacture luminescent aerogels of rare-earth oxides that can be used in opto-electronic devices.
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Identifying the global drivers of soil priming is essential to understanding C cycling in terrestrial ecosystems. We conducted a survey of soils across 86 globally-distributed locations, spanning a wide range of climates, biotic communities, and soil conditions, and evaluated the apparent soil priming effect using 13C-glucose labeling. Here we show that the magnitude of the positive apparent priming effect (increase in CO2 release through accelerated microbial biomass turnover) was negatively associated with SOC content and microbial respiration rates. Our statistical modeling suggests that apparent priming effects tend to be negative in more mesic sites associated with higher SOC contents. In contrast, a single-input of labile C causes positive apparent priming effects in more arid locations with low SOC contents. Our results provide solid evidence that SOC content plays a critical role in regulating apparent priming effects, with important implications for the improvement of C cycling models under global change scenarios.
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Belowground organisms play critical roles in maintaining multiple ecosystem processes, including plant productivity, decomposition, and nutrient cycling. Despite their importance, however, we have a limited understanding of how and why belowground biodiversity (bacteria, fungi, protists, and invertebrates) may change as soils develop over centuries to millennia (pedogenesis). Moreover, it is unclear whether belowground biodiversity changes during pedogenesis are similar to the patterns observed for aboveground plant diversity. Here we evaluated the roles of resource availability, nutrient stoichiometry, and soil abiotic factors in driving belowground biodiversity across 16 soil chronosequences (from centuries to millennia) spanning a wide range of globally distributed ecosystem types. Changes in belowground biodiversity during pedogenesis followed two main patterns. In lower-productivity ecosystems (i.e., drier and colder), increases in belowground biodiversity tracked increases in plant cover. In more productive ecosystems (i.e., wetter and warmer), increased acidification during pedogenesis was associated with declines in belowground biodiversity. Changes in the diversity of bacteria, fungi, protists, and invertebrates with pedogenesis were strongly and positively correlated worldwide, highlighting that belowground biodiversity shares similar ecological drivers as soils and ecosystems develop. In general, temporal changes in aboveground plant diversity and belowground biodiversity were not correlated, challenging the common perception that belowground biodiversity should follow similar patterns to those of plant diversity during ecosystem development. Taken together, our findings provide evidence that ecological patterns in belowground biodiversity are predictable across major globally distributed ecosystem types and suggest that shifts in plant cover and soil acidification during ecosystem development are associated with changes in belowground biodiversity over centuries to millennia.
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Biodiversidade , Modelos BiológicosRESUMO
Growth curves are monotonically increasing functions that measure repeatedly the same subjects over time. The classical growth curve model in the statistical literature is the Generalized Multivariate Analysis of Variance (GMANOVA) model. In order to model the tree trunk radius (r) over time (t) of trees on different sites, GMANOVA is combined here with the adapted PL regression model Q = A · T+E, where for b ≠ 0 : Q = Ei[-b · r]-Ei[-b · r1] and for b = 0 : Q â= Ln[r/r1], A = âinitial relative growth to be estimated, T = t-t1, and E is an error term for each tree and time point. Furthermore, Ei[-b · r] â= ∫(Exp[-b · r]/r)dr, b = -1/TPR, with TPR being the turning point radius in a sigmoid curve, and r1 at t1 is an estimated calibrating time-radius point. Advantages of the approach are that growth rates can be compared among growth curves with different turning point radiuses and different starting points, hidden outliers are easily detectable, the method is statistically robust, and heteroscedasticity of the residuals among time points is allowed. The model was implemented with dendrochronological data of 235 Pinus montezumae trees on ten Mexican volcano sites to calculate comparison intervals for the estimated initial relative growth A. One site (at the Popocatépetl volcano) stood out, with A being 3.9 times the value of the site with the slowest-growing trees. Calculating variance components for the initial relative growth, 34% of the growth variation was found among sites, 31% among trees, and 35% over time. Without the Popocatépetl site, the numbers changed to 7%, 42%, and 51%. Further explanation of differences in growth would need to focus on factors that vary within sites and over time.
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Modelos Estatísticos , Árvores/crescimento & desenvolvimento , AlgoritmosRESUMO
A very simple method to obtain the refractive index of liquids by using a rectangular glass cell and a diffraction grating engraved by fs laser ablation on the inner face of one of the walls of the cell is presented. When a laser beam impinges normally on the diffraction grating, the diffraction orders are deviated when they pass through the cell filled with the liquid to be measured. By measuring the deviation of the diffraction orders, we can determine the refractive index of the liquid.
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Lasers , Refratometria/instrumentação , Álcoois/química , Óleo de Rícino/química , Fatores de Tempo , Água/químicaRESUMO
A phase recovery procedure using interferograms acquired in highly noisy environments as severe vibrations is described. This method may be implemented when disturbances do not allow obtaining equidistant phase shifts between consecutive interferograms due to tilt-shift and nonlinearity errors introduced by the vibrating conditions. If the amount of the tilt-shift is greater than π radians, it will lead a sign change in the phase estimation. This situation cannot be handled correctly by algorithms that consider small errors or non-equidistant phase shifts during the phase shifting process under moderate disturbances. In experimental applications, it is observed that the tilt-shift is often the most dominant error in phase differences that one must deal with. In this work, a Fourier technique is used for the processing and recovering of the cosine of the phase differences. Once the phase differences are obtained, the phase encoded in the interferograms is determined. The proposed algorithm is tested in two sets of interferograms obtained from the analysis of an optical component, finding an rms error in the phase reconstructions of 0.1388 rad.
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We describe a new algorithm for phase determination from a single interferogram with closed fringes based on an unwrapping procedure. Here we use bandpass filtering in the Fourier domain, obtaining two wrapped phases with sign changes corresponding to the orientation of the applied filters. An unwrapping scheme that corrects the sign ambiguities by comparing the local derivatives is then proposed. This can be done, assuming that the phase derivatives do not change abruptly among adjacent areas as occurs with smooth continuous phase maps. The proposed algorithm works fast and is robust against noise, as demonstrated in experimental and simulated data.
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A modified form of a phase tracking method to demodulate a single fringe pattern is presented. Phase values from local areas of the interferogram are recovered by means of a spatial synchronous technique instead of solving the set of nonlinear equations obtained from the implementation of the ordinary algorithm. This results in a significant speed improvement of the method. Additionally, the robustness against noise is maintained, and the sensitivity to contrast variations is decremented with respect to the phase tracking technique.
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Keystone distortion that occurs in overhead projectors when the projecting lens head is tilted upward to a high screen is commonly observed. Here we suggest a modification of the typical overhead projector to eliminate this distortion of the image.
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The deviation of the NH(2) pseudo-first-order decay Arrhenius plots of the NH(2) + O(3) reaction at high ozone pressures measured by experimentalists, has been attributed to the regeneration of NH(2) radicals due to the subsequent reactions of the products of this reaction with ozone. Although these products have not yet been characterized experimentally, the radical H(2)NO has been postulated, because it can regenerate NH(2) radicals through the reactions: H(2)NO + O(3) --> NH(2) + O(2) and H(2)NO + O(3) --> HNO + OH + O(2). With the purpose of providing a reasonable explanation from a theoretical point of view to the kinetic observed behaviour of the NH(2) + O(3) system, we have carried ab initio electronic structure calculations on both H(2)NO + O(3) possible reactions. The results obtained in this article, however, predict that of both reactions proposed, only the H(2)NO + O(3) --> NH(2) + O(2) reaction would regenerate indeed NH(2) radicals, explaining thus the deviation of the NH(2) pseudo-first-order decay observed experimentally.