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1.
Open Forum Infect Dis ; 11(Suppl 1): S41-S47, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38532961

RESUMO

Background: Comparative costs of public health interventions provide valuable data for decision making. However, the availability of comprehensive and context-specific costs is often limited. The Enterics for Global Health (EFGH) Shigella surveillance study-a facility-based diarrhea surveillance study across 7 countries-aims to generate evidence on health system and household costs associated with medically attended Shigella diarrhea in children. Methods: EFGH working groups comprising representatives from each country (Bangladesh, Kenya, Malawi, Mali, Pakistan, Peru, and The Gambia) developed the study methods. Over a 24-month surveillance period, facility-based surveys will collect data on resource use for the medical treatment of an estimated 9800 children aged 6-35 months with diarrhea. Through these surveys, we will describe and quantify medical resources used in the treatment of diarrhea (eg, medication, supplies, and provider salaries), nonmedical resources (eg, travel costs to the facility), and the amount of caregiver time lost from work to care for their sick child. To assign costs to each identified resource, we will use a combination of caregiver interviews, national medical price lists, and databases from the World Health Organization and the International Labor Organization. Our primary outcome will be the estimated cost per inpatient and outpatient episode of medically attended Shigella diarrhea treatment across countries, levels of care, and illness severity. We will conduct sensitivity and scenario analysis to determine how unit costs vary across scenarios. Conclusions: Results from this study will contribute to the existing body of literature on diarrhea costing and inform future policy decisions related to investments in preventive strategies for Shigella.

3.
Mol Ecol ; 32(23): 6243-6259, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36862079

RESUMO

Declines in soil multifunctionality (e.gsoil capacity to provide food and energy) are closely related to changes in the soil microbiome (e.g., diversity) Determining ecological drivers promoting such microbiome changes is critical knowledge for protecting soil functions. However, soil-microbe interactions are highly variable within environmental gradients and may not be consistent across studies. Here we propose that analysis of community dissimilarity (ß-diversity) is a valuable tool for overviewing soil microbiome spatiotemporal changes. Indeed, ß-diversity studies at larger scales (modelling and mapping) simplify complex multivariate interactions and refine our understanding of ecological drivers by also giving the possibility of expanding the environmental scenarios. This study represents the first spatial investigation of ß-diversity in the soil microbiome of New South Wales (800,642 km2 ), Australia. We used metabarcoding soil data (16S rRNA and ITS genes) as exact sequence variants (ASVs) and UMAP (Uniform Manifold Approximation and Projection) as the distance metric. ß-Diversity maps (1000-m resolution)-concordance correlations of 0.91-0.96 and 0.91-0.95 for bacteria and fungi, respectively-showed soil biome dissimilarities driven primarily by soil chemistry-pH and effective cation exchange capacity (ECEC)-and cycles of soil temperature-land surface temperature (LST-phase and LST-amplitude). Regionally, the spatial patterns of microbes parallel the distribution of soil classes (e.g., Vertosols) beyond spatial distances and rainfall, for example. Soil classes can be valuable discriminants for monitoring approaches, for example pedogenons and pedophenons. Ultimately, cultivated soils exhibited lower richness due to declines in rare microbes which might compromise soil functions over time.


Assuntos
Microbiota , Solo , Austrália , Temperatura , RNA Ribossômico 16S/genética , Microbiologia do Solo , Microbiota/genética
4.
Reg Anesth Pain Med ; 46(7): 571-580, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34145070

RESUMO

BACKGROUND: There is heterogeneity in the names and anatomical descriptions of regional anesthetic techniques. This may have adverse consequences on education, research, and implementation into clinical practice. We aimed to produce standardized nomenclature for abdominal wall, paraspinal, and chest wall regional anesthetic techniques. METHODS: We conducted an international consensus study involving experts using a three-round Delphi method to produce a list of names and corresponding descriptions of anatomical targets. After long-list formulation by a Steering Committee, the first and second rounds involved anonymous electronic voting and commenting, with the third round involving a virtual round table discussion aiming to achieve consensus on items that had yet to achieve it. Novel names were presented where required for anatomical clarity and harmonization. Strong consensus was defined as ≥75% agreement and weak consensus as 50% to 74% agreement. RESULTS: Sixty expert Collaborators participated in this study. After three rounds and clarification, harmonization, and introduction of novel nomenclature, strong consensus was achieved for the names of 16 block names and weak consensus for four names. For anatomical descriptions, strong consensus was achieved for 19 blocks and weak consensus was achieved for one approach. Several areas requiring further research were identified. CONCLUSIONS: Harmonization and standardization of nomenclature may improve education, research, and ultimately patient care. We present the first international consensus on nomenclature and anatomical descriptions of blocks of the abdominal wall, chest wall, and paraspinal blocks. We recommend using the consensus results in academic and clinical practice.


Assuntos
Parede Abdominal , Anestesia por Condução , Parede Torácica , Consenso , Técnica Delphi , Humanos
5.
J Chem Phys ; 154(16): 164309, 2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33940830

RESUMO

Infrared spectroscopic studies of weakly bound clusters isolated in solid parahydrogen (pH2) that exhibit large-amplitude tunneling motions are needed to probe how quantum solvation perturbs these types of coherent dynamics. We report high resolution Fourier transform infrared absorption spectra of (HCl)2, HCl-DCl, and (DCl)2 isolated in solid pH2 in the 2.4-4.8 K temperature range. The (HCl)2 spectra show a remarkable amount of fine structures that can be rigorously assigned to vibration-rotation-tunneling transitions of (HCl)2 trapped in double substitution sites in the pH2 matrix where end-over-end rotation of the cluster is quenched. The spectra are assigned using a combination of isotopically (H/D and 35Cl/37Cl) enriched samples, polarized IR absorption measurements, and four-line combination differences. The interchange-tunneling (IT) splitting in the ground vibrational state for in-plane and out-of-plane H35Cl-H37Cl dimers is 6.026(1) and 6.950(1) cm-1, respectively, which are factors of 2.565 and 2.224 smaller than in the gas phase dimer. In contrast, the (DCl)2 results show larger perturbations where the ground vibrational state IT splitting in D35Cl-D37Cl is 1.141(1) cm-1, which is a factor of 5.223 smaller than in the gas phase, and the tunneling motion is quenched in excited intramolecular vibrational states. The results are compared to similar measurements on (HCl)2 made in liquid helium nanodroplets to illustrate the similarities and differences in how both these quantum solvents interact with large amplitude tunneling motions of an embedded chromophore.

6.
J Chem Phys ; 151(23): 234301, 2019 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-31864243

RESUMO

Isotopically enriched (3.5% 13C) and depleted (0.5% 13C) fullerene C60 molecules are isolated in parahydrogen (pH2) solids at cryogenic temperatures and studied by high resolution (0.01-0.1 cm-1) infrared (IR) absorption measurements. Spectra of natural isotopic abundance (1.1% 13C) C60 molecules isolated in solid pH2, orthodeuterium (oD2), and Ne matrix hosts serve to identify the relatively minor spectral perturbations due to the trapping environments. Spectral features observed for the four IR-active T1u modes of threefold degeneracy in Ih symmetry, namely, T1u(1) at 529.77 cm-1, T1u(2) at 578.24 cm-1, T1u(3) at 1184.7 cm-1, and T1u(4) at 1432 cm-1, are assigned to the superpositions of matrix perturbed vibrational-mode spectra of a number of 13Cn 12C60-n isotopologues. New molecular orbital calculations show the symmetry lowering effects of 13C substitution, namely, split vibrational frequencies and modified IR intensities. IR spectral patterns calculated for the 328 distinct isotopomers of 13Cn 12C60-n up to n = 3 are used to satisfactorily simulate most of the observed absorption features. For the T1u(4) mode at 1432 cm-1, the observed splitting is insensitive to the 13C abundance, indicating spectral perturbations due to Fermi resonance. Weak absorption features at 1545 cm-1 are assigned to a combination of lower frequency modes. We discuss relative and absolute band strengths for the astrophysical application of estimating C60 abundances in planetary nebulae.

7.
J Phys Chem A ; 123(51): 10893-10905, 2019 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-31769687

RESUMO

We report results of quantitative ultraviolet (UV) and infrared (IR) absorption spectroscopy experiments on Al-atom-doped cryogenic parahydrogen (pH2) solids produced by codeposition of Al vapor and pH2 gas. For Al-atom concentrations [Al] ≲200 parts-per-million (ppm), the Al/pH2 solids are optically transparent and primarily contain isolated Al atoms, with a small admixture of AlH, Al2H2, and Al2H4 molecules formed by UV irradiation and Al-atom recombination/reaction. We assign the Al/pH2 UV absorption spectrum by invoking a large (≈0.6 eV) gas-to-matrix blue shift to accompany the increase in principal quantum number in the 4s 2S ← 3p 2P1/2 transition, as previously discussed for boron-atom-doped pH2 solids. We assign a series of sharp features observed in the 4140-4155 cm-1 IR region to Al-atom-induced Q1(0) and Q1(1) absorptions of the pH2 solid. We use the solid pH2 Q1(0) + S0(0) absorption to determine the sample thickness and to establish a constant pH2 deposition efficiency independent of the flow rate. Using all of these absorption features in concert, we show that the Al-atom flux delivered by the effusive source is well described by the Knudsen-Langmuir equation, calculate an absolute Al-atom deposition yield per mass of aluminum evaporated, and demonstrate both constant Al-atom deposition and isolation efficiencies for [Al] ≲200 ppm. We discuss this unexpected constant Al-atom isolation efficiency in detail and speculate that it indicates nonuniform Al-atom recombination/reaction on the surface of the accreting sample, perhaps dominated by processes occurring near pH2 crystallite grain boundaries. We demonstrate "control" over the deposition process, which we define as the ability to set, achieve, and verify "targets" for the final Al-atom concentrations and pH2 solid thicknesses. This ability is key to sorting out the very different phenomena observed in samples targeting [Al] ≳300 ppm, which are described in the immediately following companion manuscript.

8.
J Phys Chem A ; 123(51): 10906-10918, 2019 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-31769695

RESUMO

We report the results from experiments testing the limits of chemical energy storage in Al-atom-doped cryogenic parahydrogen (pH2) solids produced by codeposition of Al vapor and pH2 gas. These results map out three regimes of behavior. As described in the immediately preceding companion manuscript, for target Al atom concentrations, [Al]target ≲ 200 parts-per-million (ppm), the Al/pH2 solids are optically transparent and primarily contain isolated Al atoms, with a small admixture of AlxHy molecules formed by Al atom recombination/reaction. For [Al]target ≳ 500 ppm, the depositions fail immediately, producing highly optically scattering solids with evidence of extensive Al atom recombination/reaction. For intermediate [Al]target concentrations, near-threshold metastable transparent solids are formed which suffer catastrophic recombination/reaction as they grow past some critical thickness. Analysis of these catastrophic events using a minimal two parameter model [Jackson. J. Chem. Phys. 1959, 31, 722-729] yields a critical Al atom concentration near [Al] ≈ 280 ppm and an Al atom diffusion length ≈ 100 µm. While this diffusion length appears unphysically large, it is roughly compatible with even larger 300-900 µm wavelengths of spatial inhomogeneities visible in images of a remnant postrecombination sample. This spatial pattern is evocative of Turing structures or perhaps the structures sometimes formed upon phase separation; however, the actual mechanism for morphogenesis remains undetermined. The largest achieved Al atom concentrations of [Al] ≈ 300 ppm are roughly two orders-of-magnitude lower than those required for advanced chemical propulsion applications.

9.
Appl Spectrosc ; 73(12): 1403-1408, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31219328

RESUMO

We report updated infrared (IR) absorption measurements on vapor-deposited cryogenic parahydrogen (pH2) solids that indicate a ≈10% systematic error in our previous approach for determining a pH2 solid's thickness (S. Tam and M.E. Fajardo. Appl. Spectrosc. 2001. 55(12): 1634-1644). We provide corrected values for the integrated absorption intensities of the Q1(0)+S0(0) and S1(0)+S0(0) bands calculated over the 4495-4520 cm-1 and 4825-4855 cm-1 regions, respectively. New polarized IR absorption spectroscopy data demonstrate the insensitivity to polarization effects of the peak intensity of the QR(0) phonon sideband near 4228 cm-1. This feature provides an even quicker way for determining the thickness of a pH2 solid than via the integrated absorptions.

10.
J Phys Chem A ; 117(50): 13504-12, 2013 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-24102285

RESUMO

We report high-resolution infrared absorption spectra of six different CO isotopologues isolated in cryogenic parahydrogen (pH2) solids. These data provide a stringent test for theories of nearly free molecular rotors in crystalline solids, such as crystal field theory, rotation-translation coupling theory, and the pseudorotating cage model. A gas-phase molecule rotates about its center-of-mass (C.M.); a trapped molecule instead rotates about its "center of interaction" (C.I.) with the trapping cage, which may differ from the C.M. for heteronuclear diatomics like CO. Isotopic manipulation of CO allows the systematic variation of the C.M. relative to the C.I. We report remarkably good straight line correlation plots between the observed matrix effects and C.M. locations. Extrapolation of these lines to the limit of vanishing matrix effects yields an "experimental prediction" of the C.I. in excellent (fortuitous?) agreement with the C.I. calculated using a linear pH2-CO-pH2 toy model.

11.
Rev Sci Instrum ; 84(3): 035106, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23556851

RESUMO

We describe the design, construction, and operation of a novel apparatus for investigating efficiency improvements in thin-film cryogenic solid positron moderators. We report results from solid neon, argon, krypton, and xenon positron moderators which illustrate the capabilities and limitations of our apparatus. We integrate a matrix isolation spectroscopy diagnostic within a reflection-geometry positron moderation system. We report the optical thickness, impurity content, and impurity trapping site structures within our moderators determined from infrared absorption spectra. We use a retarding potential analyzer to modulate the flow of slow positrons, and report positron currents vs. retarding potential for the different moderators. We identify vacuum ultraviolet emissions from irradiated Ne moderators as the source of spurious signals in our channel electron multiplier slow positron detection channel. Our design is also unusual in that it employs a sealed radioactive Na-22 positron source which can be translated relative to, and isolated from, the cryogenic moderator deposition substrate. This allows us to separate the influences on moderator efficiency of surface contamination by residual gases from those of accumulated radiation damage.

12.
J Chem Phys ; 130(24): 244508, 2009 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-19566167

RESUMO

We report the first rotationally resolved and completely assigned rovibrational spectrum for a nonhydride molecule rotating in the solid phase: carbon monoxide (CO) monomers isolated in cryogenic solid parahydrogen (p-H(2)). We employ a modified crystal field theory model, in which the CO molecular spectroscopic constants are taken as adjustable parameters, to make good spectroscopic assignments for all the observed features. We discuss the limitations of this approach and highlight the need for improved theoretical models of molecular rotation dynamics in quantum solids.

13.
J Chem Phys ; 128(1): 014505, 2008 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-18190202

RESUMO

We report polarized infrared absorption spectra of water isotopologues isolated in solid parahydrogen (pH2) which reveal the crystal field induced splittings of the 1 01<--0 00 R(0) lines in the nu1 HDO, nu3 D2O, nu3 HDO, and nu3 H2O fundamental bands. For annealed pH2 solids, these spectra also reveal a strong alignment of the hexagonal-close-packed crystallites' c axes with the deposition substrate surface normal. This alignment effect explains our failure to detect the parallel-polarized components of these R(0) lines in spectra of pH2 solids produced on a transparent deposition substrate [M. E. Fajardo et al., J. Mol. Struct. 695, 111 (2004)]. This lesson applies more generally to comparison of solid pH2 spectra obtained in different laboratories. The spectra are consistent with water monomers existing in solid pH2 as very slightly hindered rotors. The individual components of the R(0) absorption lines show a Lorentzian lineshape, with vibrational depopulation the most important source of line broadening.

14.
Mil Med ; 168(5): 404-7, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12775178

RESUMO

During a varicella outbreak among U.S. Coast Guard recruits, we examined varicella susceptibility serologically and evaluated validity of disease history. Recruits completed a questionnaire to obtain information on demographics, history of varicella disease, and varicella vaccination. Serological testing for varicella-zoster virus immunoglobulin G antibodies was conducted using an enzyme-linked immunosorbant assay. Among 513 recruits, 21 (4.1%) were seronegative to varicella-zoster virus. Recruits born in Puerto Rico were more likely than recruits born in the U.S. states to be susceptible (prevalence ratio, 4.3; 95% confidence interval, 1.4%, 13.1%). A positive disease history was highly predictive of positive serology (99.1%); however, 73% of those with a negative or uncertain history were also immune. Four (19%) susceptible recruits reported a positive varicella history. Although immunity among recruits was high, varicella outbreaks may occur in closed adult settings due to the high risks of exposure and transmission. Varicella vaccination can prevent these costly, disruptive outbreaks.


Assuntos
Varicela/epidemiologia , Surtos de Doenças , Militares , Adolescente , Adulto , Anticorpos Antivirais/sangue , Distribuição de Qui-Quadrado , Varicela/etnologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunoglobulina G/sangue , Masculino , Prevalência , Porto Rico/etnologia , Inquéritos e Questionários , Estados Unidos/epidemiologia
15.
J Am Chem Soc ; 125(30): 9218-28, 2003 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-15369378

RESUMO

The reaction of laser-ablated Al atoms and normal-H(2) during co-deposition at 3.5 K produces AlH, AlH(2), and AlH(3) based on infrared spectra and the results of isotopic substitution (D(2), H(2) + D(2) mixtures, HD). Four new bands are assigned to Al(2)H(4) from annealing, photochemistry, and agreement with frequencies calculated using density functional theory. Ultraviolet photolysis markedly increases the yield of AlH(3) and seven new absorptions for Al(2)H(6) in the infrared spectrum of the solid hydrogen sample. These frequencies include terminal Al-H(2) and bridge Al-H-Al stretching and AlH(2) bending modes, which are accurately predicted by quantum chemical calculations for dibridged Al(2)H(6), a molecule isostructural with diborane. Annealing these samples to remove the H(2) matrix decreases the sharp AlH(3) and Al(2)H(6) absorptions and forms broad 1720 +/- 20 and 720 +/- 20 cm(-1) bands, which are due to solid (AlH(3))(n). Complementary experiments with thermal Al atoms and para-H(2) at 2.4 K give similar spectra and most product frequencies within 2 cm(-1). Although many volatile binary boron hydride compounds are known, binary aluminum hydride chemistry is limited to the polymeric (AlH(3))( solid. Our experimental characterization of the dibridged Al(2)H(6) molecule provides an important link between the chemistries of boron and aluminum.

17.
Bogotá, D.C; s.n; jun. 1987. 30 p. ilus, tab.
Tese em Espanhol | LILACS | ID: lil-189974

RESUMO

La agudeza visual es importante en el aprendizaje lectoescrito, sin embargo la sitación de estado ocular ha sido descuidada por el sector salud y educación. Este estudio tiene un propósito analizar el estado de agudeza visual y su relación con rendimiento escolar en niños entre 5 y 16 años, encontrándose un 25 por ciento de niños con mala agudeza visual y un 31 por ciento con mal rendimiento escolar, siendo el problema de agudeza visual más frecuente en niños con buen rendimiento que en los de mal rendimiento, constituyendo 19 y 6 por ciento respectivamente; por lo tanto no parece haber relación directa entre el bajo rendimiento académico y la agudeza visual. La posible explicación para ésto, consiste en las estrategias compensatorias propias de la infancia que permite al niño sobresalir a pesar de sus deficiencias visuales y se afirma la importancia de exámenes precoces de agudeza visual como método de detección de problemas visuales en niños escolares


Assuntos
Criança , Baixo Rendimento Escolar , Acuidade Visual
18.
Rev. cuba. farm ; 18(1): 63-6, ene.-abr. 1984. tab
Artigo em Espanhol | LILACS | ID: lil-124235

RESUMO

Se continúa el estudio de los alcaloides de la Tabernaemontana amblyocarpa. Se informa el aislamiento de tres alcaloides indólicos que fueron identificados como: (-) coronaridina, (-) voacangina y (-) isovoacristina


Assuntos
Alcaloides/isolamento & purificação , Plantas Medicinais
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