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1.
Glob Health Action ; 16(1): 2185365, 2023 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-36940106

RESUMO

BACKGROUND: Various trainings are designed to educate nurses to become simulation educators. However, there are no good strategies to sustain their learnings and keep them engaged. We developed a series of 10 interactive digital storytelling comic episodes 'The Adventures of Super Divya (SD)' to strengthen simulation educator's facilitation knowledge, skills, confidence, and engagement. This endline evaluation presents results on the change in knowledge after watching the episodes and retention of that knowledge over 10 months. OBJECTIVES: The objectives of this pilot study are to: 1) assess the change in knowledge between the baseline and post-episode surveys; and 2) understand the retention of knowledge between the post-episode and the endline survey. METHODS: A human-centred design was used to create the episodes grounded in the lived experience of nurse simulation educators. The heroine of the comic is Divya, a 'Super Facilitator' and her nemesis is Professor Agni who wants to derail simulation as an educational strategy inside obstetric facilities. Professor Agni's schemes represent real-life challenges; and SD uses effective facilitation and communication to overcome them. The episodes were shared with a group of nurse mentors (NM) and nurse mentor supervisors (NMS) who were trained to be champion simulation educators in their own facilities. To assess change in knowledge, we conducted a baseline, nine post-episode surveys and an endline survey between May 2021 and February 2022. RESULTS: A total 110 NM and 50 NMS watched all 10 episodes and completed all of the surveys. On average, knowledge scores increased by 7-9 percentage points after watching the episodes. Comparison of survey responses obtained between 1 and 10 months suggest that the gain in knowledge was largely retained over time. CONCLUSIONS: Findings suggest that this interactive comic series was successful in a resource limited setting at engaging simulation educators and helped to maintain their facilitation knowledge over time.


Assuntos
Mentores , Logradouros Públicos , Feminino , Gravidez , Humanos , Projetos Piloto , Comunicação , Índia
2.
Artigo em Inglês | MEDLINE | ID: mdl-35270366

RESUMO

To improve the quality of intrapartum care in public health facilities of Bihar, India, a statewide quality improvement program was implemented. Nurses participated in simulation sessions to improve their clinical, teamwork, and communication skills. Nurse mentors, tasked with facilitating these sessions, received training in best practices. To support the mentors in the on-going facilitation of these trainings, we developed a digital, interactive, comic series starring "Super Divya", a simulation facilitation superhero. The objective of these modules was to reinforce key concepts of simulation facilitation in a less formal and more engaging way than traditional didactic lessons. This virtual platform offers the flexibility to watch modules frequently and at preferred times. This pilot study involved 205 simulation educators who were sent one module at a time. Shortly before sending the first module, nurses completed a baseline knowledge survey, followed by brief surveys after each module to assess change in knowledge. Significant improvements in knowledge were observed across individual scores from baseline to post-survey. A majority found Super Divya modules to be acceptable and feasible to use as a learning tool. However, a few abstract concepts in the modules were not well-understood, suggesting that more needs to be done to communicate their core meaning of these concepts.


Assuntos
Mentores , Treinamento por Simulação , Comunicação , Humanos , Projetos Piloto , Melhoria de Qualidade
3.
Environ Sci Technol ; 56(7): 4597-4609, 2022 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-35262343

RESUMO

Wildfires in forested watersheds dramatically alter stored and labile soil organic matter (SOM) pools and the export of dissolved organic matter (DOM). Ecosystem recovery after wildfires depends on soil microbial communities and revegetation and therefore is limited by the availability of nutrients, such as nitrogen-containing and labile, water-soluble compounds. However, SOM byproducts produced at different wildfire intensities are poorly understood, leading to difficulties in assessing wildfire severity and predicting ecosystem recovery. In this work, water-extractable organic matter (WEOM) from laboratory microcosms of soil burned at discrete temperatures was characterized by ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometry to study the impacts of fire temperature on SOM and DOM composition. The molecular composition derived from different burn temperatures indicated that nitrogen-containing byproducts were enriched with heating and composed of a wide range of aromatic features and oxidation states. Mass difference-based analysis also suggested that products formed during heating could be modeled using transformations along the Maillard reaction pathway. The enrichment of N-containing SOM and DOM at different soil burning intensities has important implications for ecosystem recovery and downstream water quality.


Assuntos
Microbiota , Incêndios Florestais , Reação de Maillard , Nitrogênio/análise , Solo/química
4.
Environ Sci Technol ; 54(5): 2994-3001, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-31985213

RESUMO

To simulate the effects of wildfire on the combustion process in soils and their potential to leach organic compounds into streams and groundwater, mineral soil samples were heated at temperatures of 150-550 °C. Then, the soils were leached with deionized water, filtered, and analyzed for dissolved organic carbon. The water extract was concentrated by both XAD-8 and XAD-4 resins and analyzed by C-13 nuclear magnetic resonance and liquid chromatography time-of-flight mass spectrometry. Approximately 15-20% of the water-extractable organic carbon was identified as benzene dicarboxylic acids, tricarboxylic acids, and tetracarboxylic acid isomers, commonly called BPCAs. Also identified were isomers of pyridine dicarboxylic acids and tricarboxylic acids (PCAs). The conversion of soil organic carbon to BPCAs occurs at 250 °C and reaches a maximum between 350 and 450 °C. At higher temperatures (>450 °C), the BPCA concentrations decrease, suggesting decarboxylation and conversion to carbon dioxide and water. This is the first report of BPCAs and PCAs in water-extractable organic carbon from thermally altered soil and suggest that these compounds are possible candidates for further water-quality studies in watersheds affected by wildfire. Finally, BPCAs and PCAs could contribute to the black carbon and nitrogen in seawater and are worthy of future investigation.


Assuntos
Benzeno , Solo , Ácidos Carboxílicos , Espectroscopia de Ressonância Magnética , Piridinas , Água
5.
PLoS One ; 14(10): e0224112, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31639172

RESUMO

Photolysis is one of the main transformation pathways for 2,4,6-trinitrotoluene (TNT) released into the environment. Upon exposure to sunlight, TNT is known to undergo both oxidation and reduction reactions with release of nitrite, nitrate, and ammonium ions, followed by condensation reactions of the oxidation and reduction products. In this study, compound classes of transformation products from the aqueous and solid phase photodegradation of 2,4,6-trinitrotoluene (TNT) have been identified by liquid and solid state 13C and 15N NMR. Aqueous phase experiments were performed on saturated solutions of T15NT in deionized water, natural pond water (pH = 8.3, DOC = 3.0 mg/L), pH 8.0 buffer solution, and in the presence of Suwannee River Natural Organic Matter (SRNOM; pH = 3.7), using a Pyrex-filtered medium pressure mercury lamp. Natural sunlight irradiations were performed on TNT in the solid phase and dissolved in the pond water. In deionized water, carboxylic acid, aldehyde, aromatic amine, primary amide, azoxy, nitrosophenol, and azo compounds were formed. 15N NMR spectra exhibited major peaks centered at 128 to 138 ppm, which are in the range of phenylhydroxylamine and secondary amide nitrogens. The secondary amides are proposed to represent benzanilides, which would arise from photochemical rearrangement of nitrones formed from the condensation of benzaldehyde and phenylhydroxylamine derivatives of TNT. The same compound classes were formed from sunlight irradiation of TNT in the solid phase. Whereas carboxylic acids, aldehydes, aromatic amines, phenylhydroxylamines, and amides were also formed from irradiation of TNT in pond water and in pH 8 buffer solution, azoxy and azo compound formation was inhibited. Solid state 15N NMR spectra of photolysates from the lamp irradiation of unlabeled 2,6-dinitrotoluene in deionized water also demonstrated the formation of aromatic amine, phenylhydroxylamine/ 2° amide, azoxy, and azo nitrogens.


Assuntos
Isótopos de Carbono/análise , Espectroscopia de Ressonância Magnética/métodos , Isótopos de Nitrogênio/análise , Fotólise/efeitos da radiação , Rios/química , Trinitrotolueno/metabolismo , Água/análise , Luz Solar , Trinitrotolueno/química , Trinitrotolueno/efeitos da radiação
6.
J Hazard Mater ; 320: 123-132, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27526278

RESUMO

Dissolved organic matter samples extracted from ground water at the USGS Bemidji oil spill site in Minnesota were investigated by ultrahigh resolution mass spectrometry. Principle component analysis (PCA) of the elemental composition assignments of the samples showed that the score plots for the contaminated sites were well separated from those for the uncontaminated sites. Additionally, spectra obtained from the same sampling site 7 and 19 years after the spill were grouped together in the score plot, strongly suggesting a steady state of contamination within the 12year interval. The double bond equivalence (DBE) of Ox class compounds was broader for the samples from the contaminated sites, because of the complex nature of oil and the consequent formation of compounds with saturated and/or aromatic structures from the oxygenated products of oil. In addition, Ox class compounds with a relatively smaller number of x (x<8; x=number of oxygen) and OxS1 class compounds were more abundant in the samples from the contaminated sites, because of the lower oxygen and higher sulfur contents of the oil compared to humic substances. The molecular-level signatures presented here can be a fundamental basis for in-depth analysis of oil contamination.

7.
PLoS One ; 11(5): e0154981, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27175784

RESUMO

Nitrohumic acids, produced from base extraction of coals and peats oxidized with nitric acid, have received considerable attention as soil ammendments in agriculture. The nitration chemistry however is incompletely understood. Moreover, there is a need to understand the reaction of nitric acid with natural organic matter (NOM) in general, in the context of a variety of environmental and biogeochemical processes. Suwannee River NOM, Suwannee River fulvic acid, and Pahokee Peat fulvic acid were treated with 15N-labeled nitric acid at concentrations ranging from 15% to 22% and analyzed by liquid and solid state 15N NMR spectroscopy. Bulk Pahokee peat and Illinois #6 coal were also treated with nitric acid, at 29% and 40% respectively, and analyzed by solid state 15N NMR spectroscopy. In addition to nitro groups from nitration of aromatic carbon, the 15N NMR spectra of all five samples exhibited peaks attributable to nitrosation reactions. These include nitrosophenol peaks in the peat fulvic acid and Suwannee River samples, from nitrosation of phenolic rings, and N-nitroso groups in the peat samples, from nitrosation of secondary amides or amines, the latter consistent with the peat samples having the highest naturally abundant nitrogen contents. Peaks attributable to Beckmann and secondary reactions of the initially formed oximes were present in all spectra, including primary amide, secondary amide, lactam, and nitrile nitrogens. The degree of secondary reaction product formation resulting from nitrosation reactions appeared to correlate inversely with the 13C aromaticities of the samples. The nitrosation reactions are most plausibly effected by nitrous acid formed from the reduction of nitric acid by oxidizable substrates in the NOM and coal samples.


Assuntos
Benzopiranos/análise , Carvão Mineral/análise , Ácido Nítrico/química , Solo/química , Isótopos de Carbono , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Elementos Químicos , Nitrosação
8.
Ground Water ; 54(5): 681-691, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27010754

RESUMO

Two groundwater plumes in north central Minnesota with residual crude oil sources have 20 to 50 mg/L of nonvolatile dissolved organic carbon (NVDOC). These values are over 10 times higher than benzene and two to three times higher than Diesel Range Organics in the same wells. On the basis of previous work, most of the NVDOC consists of partial transformation products from the crude oil. Monitoring data from 1988 to 2015 at one of the sites located near Bemidji, MN show that the plume of metabolites is expanding toward a lakeshore located 335 m from the source zone. Other mass balance studies of the site have demonstrated that the plume expansion is driven by the combined effect of continued presence of the residual crude oil source and depletion of the electron accepting capacity of solid phase iron oxide and hydroxides on the aquifer sediments. These plumes of metabolites are not covered by regulatory monitoring and reporting requirements in Minnesota and other states. Yet, a review of toxicology studies indicates that polar metabolites of crude oil may pose a risk to aquatic and mammalian species. Together the results suggest that at sites where residual sources are present, monitoring of NVDOC may be warranted to evaluate the fates of plumes of hydrocarbon transformation products.


Assuntos
Água Subterrânea , Petróleo , Poluentes Químicos da Água , Hidrocarbonetos , Minnesota
9.
PLoS One ; 10(11): e0142452, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26556054

RESUMO

Despite recent advances in spectroscopic techniques, there is uncertainty regarding the nature of the carbonyl groups in the asphaltene and resin fractions of crude oil, information necessary for an understanding of the physical properties and environmental fate of these materials. Carbonyl and hydroxyl group functionalities are not observed in natural abundance 13C nuclear magnetic resonance (NMR) spectra of asphaltenes and resins and therefore require spin labeling techniques for detection. In this study, the carbonyl functionalities of the resin and asphaltene fractions from a light aliphatic crude oil that is the source of groundwater contamination at the long term USGS study site near Bemidji, Minnesota, have been examined through reaction with 15N-labeled hydroxylamine and aniline in conjunction with analysis by solid and liquid state 15N NMR. Ketone groups were revealed through 15N NMR detection of their oxime and Schiff base derivatives, and esters through their hydroxamic acid derivatives. Anilinohydroquinone adducts provided evidence for quinones. Some possible configurations of the ketone groups in the resin and asphaltene fractions can be inferred from a consideration of the likely reactions that lead to heterocyclic condensation products with aniline and to the Beckmann reaction products from the initially formed oximes. These include aromatic ketones and ketones adjacent to quaternary carbon centers, ß-hydroxyketones, ß-diketones, and ß-ketoesters. In a solid state cross polarization/magic angle spinning (CP/MAS) 15N NMR spectrum recorded on the underivatized asphaltene as a control, carbazole and pyrrole-like nitrogens were the major naturally abundant nitrogens detected.


Assuntos
Petróleo/análise , Hidrocarbonetos Policíclicos Aromáticos/química , Isótopos de Carbono , Espectroscopia de Ressonância Magnética , Metilação , Minnesota , Isótopos de Nitrogênio , Bases de Schiff/química
10.
J Environ Qual ; 41(3): 865-81, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22565268

RESUMO

One of the concerns regarding the safety and efficacy of ultraviolet radiation for treatment of drinking water and wastewater is the fate of nitrate, particularly its photolysis to nitrite. In this study, N NMR was used to establish for the first time that UV irradiation effects the incorporation of nitrate and nitrite nitrogen into aquatic natural organic matter (NOM). Irradiation of (15)N-labeled nitrate in aqueous solution with an unfiltered medium pressure mercury lamp resulted in the incorporation of nitrogen into Suwannee River NOM (SRNOM) via nitrosation and other reactions over a range of pH from approximately 3.2 to 8.0, both in the presence and absence of bicarbonate, confirming photonitrosation of the NOM. The major forms of the incorporated label include nitrosophenol, oxime/nitro, pyridine, nitrile, and amide nitrogens. Natural organic matter also catalyzed the reduction of nitrate to ammonia on irradiation. The nitrosophenol and oxime/nitro nitrogens were found to be susceptible to photodegradation on further irradiation when nitrate was removed from the system. At pH 7.5, unfiltered irradiation resulted in the incorporation of (15)N-labeled nitrite into SRNOM in the form of amide, nitrile, and pyridine nitrogen. In the presence of bicarbonate at pH 7.4, Pyrex filtered (cutoff below 290-300 nm) irradiation also effected incorporation of nitrite into SRNOM as amide nitrogen. We speculate that nitrosation of NOM from the UV irradiation of nitrate also leads to production of nitrogen gas and nitrous oxide, a process that may be termed photo-chemodenitrification. Irradiation of SRNOM alone resulted in transformation or loss of naturally abundant heterocyclic nitrogens.


Assuntos
Nitratos/química , Nitritos/química , Rios/química , Poluentes Químicos da Água/química , Carbono/química , Carbono/metabolismo , Isótopos de Carbono , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Nitrogênio/química , Nitrogênio/metabolismo , Isótopos de Nitrogênio , Fotoquímica , Raios Ultravioleta
11.
J Environ Qual ; 39(4): 1416-28, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20830929

RESUMO

The time course photodegradation of the Nordic aquatic fulvic and humic acids and Suwannee River XAD-4 acids subjected to UV irradiation with an unfiltered medium pressure mercury lamp was studied by liquid-state 13C nuclear magnetic resonance. Photodecarboxylation was a significant pathway in all cases. Decreases in ketone, aromatic, and O-alkyl carbons were observed throughout the course of the irradiations, whereas C-alkyl carbons resisted photodegradation. Peaks attributable to the low-molecular-weight photodegradation products bicarbonate, formate, acetate, and succinate grew in intensity with irradiation time. The final products of the irradiations were decarboxylated, hydrophobic, predominantly C-alkyl and O-alkyl materials that were resistant to further photodegradation. The total amount of carbon susceptible to loss appeared to be related mainly to the total concentration of carbonyl and aromatic carbons and partly to the concentration of O-alkyl carbons in the fulvic, humic, and XAD-4 acids. The carbon losses for Nordic fulvic, Nordic Humic, Suwannee fulvic, and Suwannee XAD-4 acids were estimated to be 75, 63, 56, and 17%, respectively. More detailed analyses of the effects of irradiation on the carbonyl functionality in Nordic humic acid and Laurentian soil fulvic acid through reaction with hydroxylamine in conjunction with 15N nuclear magnetic resonance analysis confirmed preferential photodegradation of the quinone/hydroquinone functionality over ketone groups and the loss of ester groups in Laurentian fulvic acid.


Assuntos
Substâncias Húmicas/análise , Fotólise , Água/química , Benzopiranos/química , Isótopos de Carbono , Monitoramento Ambiental , Compostos de Pirvínio , Poluentes Químicos da Água/química , Poluentes Químicos da Água/efeitos da radiação , Purificação da Água/métodos
12.
Environ Sci Technol ; 42(7): 2542-50, 2008 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-18504994

RESUMO

Large-scale aerobic windrow composting has been used to bioremediate washout lagoon soils contaminated with the explosives TNT (2,4,6-trinitrotoluene) and RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) at several sites within the United States. We previously used 15N NMR to investigate the reduction and binding of T15NT in aerobic bench-scale reactors simulating the conditions of windrow composting. These studies have been extended to 2,4-dinitrotoluene (2,4DNT) and 2,6-dinitrotoluene (2,6DNT), which, as impurities in TNT, are usually presentwherever soils have been contaminated with TNT. Liquid-state 15N NMR analyses of laboratory reactions between 4-methyl-3-nitroaniline-15N, the major monoamine reduction product of 2,4DNT, and the Elliot soil humic acid, both in the presence and absence of horseradish peroxidase, indicated that the amine underwent covalent binding with quinone and other carbonyl groups in the soil humic acid to form both heterocyclic and non-heterocyclic condensation products. Liquid-state 15N NMR analyses of the methanol extracts of 20 day aerobic bench-scale composts of 2,4-di-15N-nitrotoluene and 2,6-di-15N-nitrotoluene revealed the presence of nitrite and monoamine, but not diamine, reduction products, indicating the occurrence of both dioxygenase enzyme and reductive degradation pathways. Solid-state CP/MAS 15N NMR analyses of the whole composts, however, suggested that reduction to monoamines followed by covalent binding of the amines to organic matter was the predominant pathway.


Assuntos
Aerobiose , Dinitrobenzenos/química , Espectroscopia de Ressonância Magnética/métodos , Solo , Isótopos de Nitrogênio
13.
Environ Sci Technol ; 38(7): 2167-74, 2004 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-15112821

RESUMO

TNT (trinitrotoluene) is a contaminant of global environmental significance, yet determining its environmental fate has posed longstanding challenges. To date, only differential extraction-based approaches have been able to determine the presence of covalently bound, reduced forms of TNT in field soils. Here, we employed thermal elution, pyrolysis, and gas chromatography/mass spectrometry (GC/MS) to distinguish between covalently bound and noncovalently bound reduced forms of TNT in soil. Model soil organic matter-based matrixes were used to develop an assay in which noncovalently bound (monomeric) aminodinitrotoluene (ADNT) and diaminonitrotoluene (DANT) were desorbed from the matrix and analyzed at a lower temperature than covalently bound forms of these same compounds. A thermal desorption technique, evolved gas analysis, was initially employed to differentiate between covalently bound and added 15N-labeled monomeric compounds. A refined thermal elution procedure, termed "double-shot analysis" (DSA), allowed a sample to be sequentially analyzed in two phases. In phase 1, all of an added 15N-labeled monomeric contaminant was eluted from the sample at relatively low temperature. In phase 2 during high-temperature pyrolysis, the remaining covalently bound contaminants were detected. DSA analysis of soil from the Louisiana Army Ammunition Plant (LAAP; approximately 5000 ppm TNT) revealed the presence of DANT, ADNT, and TNT. After scrutinizing the DSA data and comparing them to results from solvent-extracted and base/ acid-hydrolyzed LAAP soil, we concluded that the TNT was a noncovalently bound "carryover" from phase 1. Thus, the pyrolysis-GC/MS technique successfully defined covalently bound pools of ADNT and DANT in the field soil sample.


Assuntos
Poluentes do Solo/análise , Trinitrotolueno/análise , Cromatografia Gasosa-Espectrometria de Massas , Incineração , Isótopos de Nitrogênio/análise , Sensibilidade e Especificidade , Temperatura
14.
Environ Sci Technol ; 38(7): 2224-31, 2004 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-15112828

RESUMO

Alkaline hydrolysis has been investigated as a nonbiological procedure for the destruction of 2,4,6-trinitrotoluene (TNT) in explosives contaminated soils and munitions scrap. Nucleophilic substitutions of the nitro and methyl groups of TNT by hydroxide ion are the initial steps in the alkaline degradation of TNT. Potential applications of the technique include both in situ surface liming and ex situ alkaline treatment of contaminated soils. A number of laboratory studies have reported the formation of an uncharacterized polymeric material upon prolonged treatment of TNT in base. As part of an overall assessment of alkaline hydrolysis as a remediation technique, and to gain a better understanding of the chemical reactions underlying the hydrolysis/polymerization process, the soluble and precipitate fractions of polymeric material produced from the calcium hydroxide hydrolysis of unlabeled and 15N-labeled TNT were analyzed by elemental analysis and 13C and 15N nuclear magnetic resonance spectroscopy. Spectra indicated that reactions leading to polymerization included nucleophilic displacement of nitro groups by hydroxide ion, formation of ketone, carboxyl, alcohol, ether, and other aliphatic carbons, conversion of methyl groups to diphenyl methylene carbons, and recondensation of aromatic amines and reduced forms of nitrite, including ammonia and possibly hydroxylamine, into the polymer. Compared to the distribution of carbons in TNT as 14% sp3- and 86% sp2-hybridized, the precipitate fraction from hydrolysis of unlabeled TNT contained 33% sp3- and 67% sp2-hybridized carbons. The concentration of nitrogen in the precipitate was 64% of that in TNT. The 15N NMR spectra showed that, in addition to residual nitro groups, forms of nitrogen present in the filtrate and precipitate fractions include aminohydroquinone, primary amide, indole, imine, and azoxy, among others. Unreacted nitrite was recovered in the filtrate fraction. The toxicities and susceptibilities to microbial or chemical degradation of the polymeric materials remain unknown.


Assuntos
Poluentes do Solo/análise , Trinitrotolueno/química , Isótopos de Carbono , Precipitação Química , Monitoramento Ambiental , Hidrólise , Espectroscopia de Ressonância Magnética , Isótopos de Nitrogênio , Polímeros/química
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