RESUMO
Volatile phenols have been implicated as contributors to off-odors associated with taints from bushfire smoke and microbial spoilage. Various methods for the amelioration of off-odors have been evaluated, but to date, they have not included cyclodextrin (CD) polymers. In the current study, two CD polymers were prepared from ß- and γ-CD, using hexamethylene diisocyanate (HDI) as a crosslinking agent. Adsorption tests were performed with four volatile phenols (guaiacol, 4-methylguaiacol, 4-ethylguaiacol and 4-ethylphenol) at concentrations up to 1 mg/L. The removal of volatile phenols by CD polymers achieved equilibrium almost instantly, with isotherm tests suggesting an adsorption capacity of 20.7 µg of volatile phenol per gram of polymer. Langmuir and Freundlich models were subsequently used to fit the data. In batch adsorption tests, the CD polymers achieved 45 to 77% removal of volatile phenols. Polymer reusability was also evaluated and was found to be excellent. A comparison between volatile phenol adsorption by CDs vs. CD polymers, determined using a novel four-phase headspace solid-phase microextraction (HS-SPME) method for gas chromatography-mass spectrometry (GC-MS), suggests CD polymers offer several advantages for use by the wine industry.
Assuntos
Reagentes de Ligações Cruzadas/química , Ciclodextrinas/química , Fenóis/isolamento & purificação , Polímeros/química , Vinho/análise , Adsorção , Espectroscopia de Prótons por Ressonância Magnética , Temperatura , VolatilizaçãoRESUMO
Volatile phenols exist in wine and can be markers for Brettanomyces and smoke taint off-odors. Cyclodextrins (CDs) are found to be capable of forming inclusion complexes with volatile phenols. Cross peaks on 2D 1H ROESY nuclear magnetic resonance (NMR) spectra demonstrated inclusion of volatile phenols in the ß-CD cavity, while difference tests confirmed this resulted in a perceptible reduction of their sensory impact. However, a conventional headspace solid phase microextraction (HS-SPME) method using an isotopically labelled normalizing standard failed to quantify the residual volatile phenols by gas chromatography-mass spectrometry (GC-MS) because of inclusion of the standard by the CDs. A new method involving an additional liquid phase was developed and validated for quantitation of volatile phenols in the presence of CDs. The retention of eight volatile phenols by α-, ß-, and γ-CD was subsequently studied.
Assuntos
Brettanomyces/química , Ciclodextrinas/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Espectroscopia de Ressonância Magnética/métodos , Fenóis/químicaRESUMO
3-Isobutyl-2-methoxypyrazine (IBMP), the most prevalent grape-derived methoxypyrazine, can contribute green bell pepper, vegetative and herbaceous aromas and flavours to wines. At elevated concentrations, this potent odorant may mask desirable fruity and floral aromas in wine and may be considered as a fault. A new remediation method for wines with elevated IBMP levels has been trialled using magnetic polymers, prepared in the same way as ordinary polymers but with the incorporation of iron oxide nanoparticles as magnetic substrates. Characterisation by Fourier transform-infrared (FTIR) spectroscopy and scanning electron microscopy (SEM) showed no difference between thermally synthesised and microwave synthesised polymers. Magnetic polymers were found to have removed over 40% of the IBMP present in spiked model wine and white wine within ten minutes. The addition of magnetic nanoparticles and microwave-induced polymerisation did not affect the adsorption properties of the polymer in model wine and the polymer could be regenerated at least five times. Both Langmuir and Freundlich isotherms were found to fit the data for both types of polymer. However, attempts to produce imprinted polymers were not achieved, as they were found not to be differentiated from non-imprinted counterparts via adsorption tests.
Assuntos
Magnetismo , Polímeros/química , Pirazinas/análise , Vinho/análise , Adsorção , Cromatografia Gasosa-Espectrometria de Massas , Cinética , Microextração em Fase Sólida , Espectroscopia de Infravermelho com Transformada de Fourier , Estatística como Assunto , TemperaturaRESUMO
Increasing health portal participation actively engages patients in their care and improves outcomes. The primary aim for this project was to increase patient health portal utilization. Nurses used a tablet-based demo to teach patients how to navigate the health portal. Assigning health videos to the portal was a tactic used to increase utilization. Each patient participant was surveyed about health portal utilization at initial nurse navigator appointment, day of procedure, and 30 days after discharge. Seventy-three percent (n = 14) of the 19 selected patients received the intervention; 36% (n = 4) of patients reported using a health portal feature; meaningful use metric preintervention increased from 12% to 16% after the intervention; 16% and 18% of patients viewed assigned videos in their health portal prior to procedure and after hospital discharge. Patients need a reason to access their health portal. Education alone is not enough to motivate patient portal use. Further research is needed to specify what tactics are required to motivate patients to use their health portals.
Assuntos
Cardiopatias/psicologia , Comportamento de Busca de Informação , Participação do Paciente/estatística & dados numéricos , Portais do Paciente/estatística & dados numéricos , Idoso , Registros Eletrônicos de Saúde/estatística & dados numéricos , Prática Clínica Baseada em Evidências/métodos , Feminino , Humanos , Internet/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Acesso dos Pacientes aos Registros/psicologia , Acesso dos Pacientes aos Registros/normas , Participação do Paciente/psicologia , Portais do Paciente/normas , Satisfação do Paciente , Projetos PilotoRESUMO
The healthcare provider landscape is rapidly changing. Given the imminent retirement of baby boomer physicians, implementation of the Affordable Care Act, and the increased utilization of health care services by an ever-aging population, the supply of providers cannot keep pace with the demand for services. This has led to an increased utilization of advanced clinical practitioners (ACPs). This article shows how one large highly-matrixed health care system approached identifying this workforce, and how thought leaders worked collaboratively with physicians, administrators, and ACPs to meet a growing demand for providers. Carolinas HealthCare System developed a 3-pronged approach to this opportunity. The development of a Center for Advanced Practice was explored and implemented. This Center serves as a 2-way conduit of information and ideas between system administrators and providers. It also serves as a central source of regulatory and practice information for administrators and providers. The growing number of open ACP positions, along with the reluctance to employ novice and new graduate ACPs, led to the development of a postgraduate transition to practice fellowship program. This program's clinical tracks and curriculum are described. Finally, a collaborative effort between the health care system and a local university resulted in the local offering of an acute care nurse practitioner program, which allowed system nurses to continue their education without the need for relocation. Higher satisfaction and engagement, lower turnover, better career opportunities, more satisfied administrators, and physicians all contributed to the overwhelming success of this initiative.
Assuntos
Atenção à Saúde/métodos , Atenção à Saúde/tendências , Competência Clínica/normas , Educação Continuada/métodos , Bolsas de Estudo/métodos , Humanos , Satisfação no Emprego , Patient Protection and Affordable Care Act/tendências , Seleção de Pessoal/métodos , Seleção de Pessoal/normasRESUMO
Two unstable hydroperoxides, 6b and 10a, and 13 downstream sesquiterpenoids have been isolated from the autoxidation mixture of the bicyclic sesquiterpene α-guaiene (1) on cellulose filter paper. One of the significant natural products isolated was rotundone (2), which is the only known impact odorant displaying a peppery aroma. Other products included corymbolone (4a) and its C-6 epimer 4b, the (2R)- and (2S)-rotundols (7a/b), and several hitherto unknown epimers of natural chabrolidione A, namely, 7-epi-chabrolidione A (3a) and 1,7-epi-chabrolidione A (3b). Two 4-hydroxyrotundones (8a/b) and a range of epoxides (9a/b and 5a/b) were also formed in significant amounts after autoxidation. Their structures were elucidated on the basis of spectroscopic data and X-ray crystallography, and a number of them were confirmed through total synthesis. The mechanisms of formation of the majority of the products may be accounted for by initial formation of the 2- and 4-hydroperoxyguaienes (6a/b and 10a/b) followed by various fragmentation or degradation pathways. Given that α-guaiene (1) is well known to exist in the essential oils of numerous plants, coupled with the fact that aerial oxidation to form this myriad of downstream oxidation products occurs readily at ambient temperature, suggests that many of them have been overlooked during previous isolation studies from natural sources.
Assuntos
Azulenos/química , Azulenos/isolamento & purificação , Peróxido de Hidrogênio/isolamento & purificação , Sesquiterpenos de Guaiano/química , Sesquiterpenos de Guaiano/isolamento & purificação , Cristalografia por Raios X , Peróxido de Hidrogênio/química , Estrutura Molecular , Oxirredução , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , EstereoisomerismoRESUMO
This paper presents a multipurpose and low cost sensor for the simultaneous monitoring of temperature and ullage of wine in barrels in two of the most important stages of winemaking, that being fermentation and maturation. The distributed sensor subsystem is imbedded within the bung of the barrel and runs on battery for a period of at least 12 months and costs around $27 AUD for all parts. In addition, software was designed which allows for the remote transmission and easy visual interpretation of the data for the winemaker. Early warning signals can be sent when the temperature or ullage deviates from a winemakers expectations so remedial action can be taken, such as when topping is required or the movement of the barrels to a cooler cellar location. Such knowledge of a wine's properties or storage conditions allows for a more precise control of the final wine quality.
Assuntos
Temperatura , Vinho/análise , Tecnologia sem Fio/instrumentação , Custos e Análise de Custo , Fermentação , Internet , Propriedades de Superfície , Vinho/economia , Tecnologia sem Fio/economiaRESUMO
A synthesis of carbocyclic sugars from carbohydrate-derived dialdehydes using organocatalysis has been developed. Sorbitol, mannitol, and galactitol were converted via 1,6-tritylation, perbenzylation or permethylation, detritylation, and Swern oxidation into 2,3,4,5-tetra-O-alkyl-dialdoses that were cyclized via the benzoin reaction promoted by a triazolium carbene. Manno- and galacto-configured dialdehydes gave predominantly single inosose stereoisomers in up to 75% yield if the mixture was acetylated prior to isolation while the gluco-dialdehyde afforded a mixture of three stereoisomers in 61% overall yield. The inososes were stereospecifically reduced using sodium borohydride and then deprotected to give allo- and epi-inositol in good yield that confirmed the structural and stereochemical assignments.
RESUMO
The diastereomeric ratio of epoxidation of the internally bridged carbon-carbon double bond of guaiol (1a) is strongly influenced by the combined effects of the types of remote protecting groups on the hydroxyisopropyl side chain, choice of solvent, and epoxidizing reagent. This observation has allowed us to devise concise stereoselective syntheses of a range of guaiane-type sesquiterpenoids via an epoxidation, ring-opening/elimination, and functionality manipulation sequence. Natural products guaia-4(5)-en-11-ol (2a), guaia-5(6)-en-11-ol (3), and aciphyllene (4a) and epimers of the recently isolated natural products, 1-epi-guaia-4(5)-en-11-ol (2b), 1-epi-aciphyllene (4b), and 1-epi-melicodenones C (5a) and E (6a), were synthesized in good yields in relatively few steps.
Assuntos
Sesquiterpenos de Guaiano/síntese química , Sesquiterpenos/síntese química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Sesquiterpenos/química , Sesquiterpenos de Guaiano/química , EstereoisomerismoRESUMO
The title compound, C15H24O2 [systematic name: (4S,4aR,6R,8aR)-4a-hy-droxy-4,8a-dimethyl-6-(prop-1-en-2-yl)octahydro-naphthalen-1(2H)-one], features two edge-shared six-membered rings with the hydroxyl and methyl substituents at this bridge being trans. One adopts a flattened chair conformation with the C atoms bearing the carbonyl and methyl substituents lying 0.5227â (16) and 0.6621â (15)â Å, respectively, above and below the mean plane through the remaining four C atoms (r.m.s. deviation = 0.0145â Å). The second ring, bearing the prop-1-en-2-yl group, has a chair conformation. Supra-molecular helical chains along the b axis are found in the crystal packing, which are sustained by hy-droxy-carbonyl O-Hâ¯O hydrogen bonding.
RESUMO
Four independent mol-ecules (A-D) comprise the asymmetric unit of the title compound, C15H26O2, which differ only in the relative orientations of the terminal -C(Me)2OH groups [e.g. the range of Cmethyl-ene-Cmethine-Cquaternary-Ohy-droxy torsion angles is 52.7â (7)-57.1â (6)°, where the Cmethyl-ene atom is bound to an epoxide C atom]. The five-membered rings adopt envelope conformations, with the methyl-ene C atom adjacent to the methine C atom being the flap atom in each case. In each mol-ecule, the conformation of the seven-membered ring is a half-chair, with the Cmethyl-ene-Cmethine bond, flanked by methyl-ene C atoms, being the back of the chair. Supra-molecular helical chains along the b axis are found in the crystal packing, sustained by hy-droxy-epoxide O-Hâ¯O hydrogen bonding. Mol-ecules of A self-associate into a chain as do those of D. A third independent chain comprising B and C mol-ecules is also formed. The studied crystal is a pseudo-merohedral twin (minor component ca 21%).
RESUMO
Objectives: Advanced Trauma Life Support (ATLS) focuses on care of injured patients in the first hour of resuscitation. Expanded demand for courses has led to a concurrent need for new instructors. Nurse practitioners and physician assistants (NPs/PAs) work on trauma services and duties include patient, staff, and outreach education. The goal of this project was to assess NP/PA self-reported knowledge and skills pertinent to ATLS and identify potential barriers to becoming instructors. Materials: This was a voluntary 91-question survey emailed to NP/PA lists obtained from professional societies and online social media channels. NPs/PAs completed a survey reflecting self-reported knowledge, experience, comfort level, and barriers to teaching ATLS interactive discussions and skills. Responses were recorded using a Likert scale and results were documented as percentages. Number of years of experience versus perceived knowledge and comfort teaching were compared using a χ2 test of independence. Results: There were 1696 completed surveys. Most NPs/PAs thought they had adequate knowledge and experience to teach interactive discussions and skills. Those with more years of experience and those who completed more ATLS courses had higher percentages. The number 1 barrier to teaching was lack of formal teaching experience followed by perceived hierarchy concerns. Experience and comfort with skills that fell below 50% were pediatric airway (49.5%), needle and surgical cricothyrotomy (49.8% and 44.8%), diagnostic peritoneal lavage (21.6%), and venous cutdown (20.8%). Conclusion: NPs/PAs with experience in trauma reported having the knowledge and skill to teach ATLS. A majority are comfortable teaching interactive discussions and skills for which they are knowledgeable. The primary barrier to teaching was lack of formal teaching experience, which is covered in the ATLS Instructor course. Training NPs/PAs to become instructors would increase the instructor base and allow for increased promulgation of ATLS and trauma education. Level of evidence: IV.
RESUMO
RATIONALE: Stilbenoids are secondary plant metabolites responsible for the protection of multiple plant species including grape vine from bacterial and fungal infection. Red wine has been shown to be a major source of these compounds in the human diet, where they display an array of health benefits. Providing a more complete profile of the stilbenoids present in red wine, this study detects 41 stilbenoid compounds, 23 of which have never before been detected in red wine. METHODS: Red wine extracts were scanned using an ultra-high-performance liquid chromatograph coupled to a hybrid quadrupole time-of-flight mass analyzer. Multiple targeted MS/MS precursor ion scan experiments were performed using electrospray ionization operated in negative mode. Precursor ion masses were scanned for the monomeric and oligomeric stilbenoids, as well as modifications such as O-glycosylation, methoxylation and oxidation products of these compounds. Accurate mass precursor and characteristic product ions afforded partial structural elucidation and assignment of these compounds. RESULTS: A total of 41 (both known and novel) stilbenoids were detected in extracted red wine. In addition to the well-known monomeric stilbenes, several resveratrol-resveratrol homodimers (m/z 453.1344), resveratrol-piceatannol heterodimers (m/z 469.1293) and piceatannol-piceatannol homodimers (m/z 485.1236) were detected. Modified dimers of resveratrol including O-glycosylated (m/z 615.1872), methoxylated (m/z 485.1606) and oxidized (m/z 471.1449) dimers were also detected. Multiple trimers of resveratrol (m/z 679.1978) were detected for the first time in red wine, as well as some known and some novel stilbenoid tetramers (m/z 905.2604). CONCLUSIONS: In summary, 41 stilbenoids were detected in red wine, 23 for the first time. Both monomeric and oligomeric stilbenoids were partially identified and assigned by their accurate mass precursor ions and characteristic stilbenoid fragmentation patterns. Knowledge gained from these experiments contributes to a more complete understanding of the origin of the beneficial properties of red wine.
Assuntos
Estilbenos/química , Vitis/química , Vinho/análise , Cromatografia Líquida de Alta Pressão/métodos , Estrutura Molecular , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodosRESUMO
Together with the sweet principle component glycyphyllin A (3), seven phenolic compounds including two new dihydrochalcone rhamnopyranosides, glycyphyllin B (1) and glycyphyllin C (2), and five known flavonoids, catechin (4), kaempferol-3-O-ß-D-glucopyranoside (5), quercetin-3-O-ß-D-glucopyranoside (6), kaempferol-3-O-ß-neohesperidoside (7), and 2R,3R-dihydrokaempferol-3-O-ß-D-glucopyranoside (8), have been isolated from the ethanolic extract of the leaves of Smilax glyciphylla for the first time. The structures of these compounds were characterized by spectroscopic methods including UV, MS, and 1D and 2D NMR. In vitro antioxidant capacity tests employing FRAP and DPPH assays indicated that 1, 4, and 6 exhibited potent antioxidant activity and are the key phenolics responsible for the antioxidant activity of the leaf extract of S. glyciphylla.
Assuntos
Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Quempferóis/isolamento & purificação , Quempferóis/farmacologia , Fenóis/isolamento & purificação , Fenóis/farmacologia , Smilax/química , Antioxidantes/química , Austrália , Compostos de Bifenilo/farmacologia , Flavonoides/química , Glicosídeos/química , Quempferóis/química , Ressonância Magnética Nuclear Biomolecular , Oxirredução , Fenóis/química , Picratos/farmacologia , Folhas de Planta/químicaRESUMO
The entire mol-ecule of pallidol hexa-acetate {systematic name: (±)-(4bR,5R,9bR,10R)-5,10-bis-[4-(acet-yloxy)phen-yl]-4b,5,9b,10-tetra-hydro-indeno-[2,1-a]indene-1,3,6,8-tetrayl tetra-acetate} is completed by the application of twofold rotational symmetry in the title ethyl acetate solvate, C40H34O12·C4H8O2. The ethyl acetate mol-ecule was highly disordered and was treated with the SQUEEZE routine [Spek (2009 â¶). Acta Cryst. D65, 148-155]; the crystallographic data take into account the presence of the solvent. In pallidol hexa-acetate, the dihedral angle between the fused five-membered rings (r.m.s. deviation = 0.100â Å) is 54.73â (6)°, indicating a significant fold in the mol-ecule. Significant twists between residues are also evident as seen in the dihedral angle of 80.70â (5)° between the five-membered ring and the pendent benzene ring to which it is attached. Similarly, the acetate residues are twisted with respect to the benzene ring to which they are attached [C-O(carb-oxy)-C-C torsion angles = -70.24â (14), -114.43â (10) and -72.54â (13)°]. In the crystal, a three-dimensional architecture is sustained by C-Hâ¯O inter-actions which encompass channels in which the disordered ethyl acetate mol-ecules reside.
RESUMO
The ozonolysis of bicyclic 1,2-dioxines was investigated using a variety of 1,4-disubstituted 1,2-dioxines along with a 1,3-dialkyl and steroidal example, with yields ranging from moderate to excellent. Two different pathways were observed upon reaction of the 1,4-disubstituted 1,2-dioxines with ozone; one pathway saw the "expected" results, that is, cleavage of the olefinic moiety with generation of 1,4-dicarbonyl 1,2-dioxines, while the other pathway revealed a previously unobserved rearrangement involving cleavage of the peroxide linkage along with loss of either CO or CO(2). Several unsymmetrical ozonolyses were also performed to further investigate the origins of this rearrangement, and initial mechanistic insights into the fragmentation pathways are discussed.
Assuntos
Compostos Bicíclicos com Pontes/química , Dioxinas/química , Ozônio/química , Estrutura MolecularRESUMO
Sulfur dioxide (SO(2)) is important in the winemaking process as it aids in preventing microbial growth and the oxidation of wine. These processes and others consume the SO(2) over time, resulting in wines with little SO(2) protection. Furthermore, SO(2) and sulfiting agents are known to be allergens to many individuals and for that reason their levels need to be monitored and regulated in final wine products. Many of the current techniques for monitoring SO(2) in wine require the SO(2) to be separated from the wine prior to analysis. This investigation demonstrates a technique capable of measuring free sulfite concentrations in low volume liquid samples in white wine. This approach adapts a known colorimetric reaction to a suspended core optical fiber sensing platform, and exploits the interaction between guided light located within the fiber voids and a mixture of the wine sample and a colorimetric analyte. We have shown that this technique enables measurements to be made without dilution of the wine samples, thus paving the way towards real time in situ wine monitoring.
Assuntos
Sulfitos/análise , Dióxido de Enxofre/análise , Vinho/análise , Colorimetria/instrumentação , Colorimetria/métodos , Corantes/química , Fibras Ópticas , Corantes de Rosanilina/química , Análise Espectral , Sulfitos/química , Dióxido de Enxofre/química , Toluidinas/químicaRESUMO
The title compound, C(23)H(30)O(9), has an approximate T-shape with the tert-butyl ester groups lying either side of the benzene ring. The acetyl group is almost perpendicular to the benzene ring to which it is connected [C-C-O-C torsion angle = -106.7â (3)°]. The conformation about the C=C double bond [1.331â (4)â Å] is E. Linear supra-molecular chains along the a axis mediated by hy-droxy-carbonyl O-Hâ¯O hydrogen bonds feature in the crystal packing. The same H atom is also involved in an intra-molecular O-Hâ¯O inter-action.
RESUMO
In the title mol-ecule, C(24)H(32)O(10), one tert-butyl ester group is folded towards the central benzene ring while the other is directed away. The acetyl group is almost perpendicular to the benzene ring to which it is connected [C-C-O-C torsion angle = 90.4â (12)°]. The conformation about the ethene bond [1.313â (7)â Å] is E. The atoms of the benzene ring and its attached ester group and part of the hy-droxy tert-butyl ester side chain are disordered over two sets of sites in a 50:50 ratio. Linear supra-molecular chains along the a axis mediated by hy-droxy-carbonyl O-Hâ¯O hydrogen bonds feature in the crystal packing. The same H atom also partakes in an intra-molecular O-Hâ¯O inter-action.
RESUMO
Since its introduction a few years ago, the linear ion trap Orbitrap (LTQ Orbitrap) instrument has become a powerful tool in proteomics research. For high resolution mass spectrometry measurements ions are accumulated in the linear ion trap and passed on to the Orbitrap analyzer. Simultaneously with acquisition of this signal, the major peaks are isolated in turn, fragmented and recorded at high sensitivity in the linear ion trap, combining the strengths of both mass analyzer technologies. Here we describe a next generation LTQ Orbitrap system termed Velos, with significantly increased sensitivity and scan speed. This is achieved by a vacuum interface using a stacked ring radio frequency ion guide with 10-fold higher transfer efficiency in MS/MS mode and 3-5-fold in full scan spectra, by a dual pressure ion trap configuration, and by reduction of overhead times between scans. The first ion trap efficiently captures and fragments ions at relatively high pressure whereas the second ion trap realizes extremely fast scan speeds at reduced pressure. Ion injection times for MS/MS are predicted from full scans instead of performing automatic gain control scans. Together these improvements routinely enable acquisition of up to ten fragmentation spectra per second. Furthermore, an improved higher-energy collisional dissociation cell with increased ion extraction capabilities was implemented. Higher-collision energy dissociation with high mass accuracy Orbitrap readout is as sensitive as ion trap MS/MS scans in the previous generation of the instrument.