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1.
J Am Chem Soc ; 146(21): 14587-14592, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38716882

RESUMEN

The ability to controllably move gaseous ions is an essential aspect of ion-based spectrometry (e.g., mass spectrometry and ion mobility spectrometry) as well as materials processing. At higher pressures, ion motion is largely governed by diffusion and multiple collisions with neutral gas molecules. Thus, high-pressure ion optics based on electrostatics require large fields, radio frequency drives, complicated geometries, and/or partially transmissive grids that become contaminated. Here, we demonstrate that low-power standing acoustic waves can be used to guide, block, focus, and separate beams of ions akin to electrostatic ion optics. Ions preferentially travel through the static-pressure regions ("nodes") while neutral gas does not appear to be impacted by the acoustic field structure and continues along a straight trajectory. This acoustic ion manipulation (AIM) approach has broad implications for ion manipulation techniques at high pressure, while expanding our fundamental understanding of the behavior of ions in gases.

2.
Early Child Educ J ; : 1-20, 2023 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-37360589

RESUMEN

This study aimed to obtain consensus on physical activity (PA) and sedentary behaviour (SB) policy items for use in Canadian childcare settings. Purposeful sampling of Canadian experts in PA/SB (n = 19) and Early Childhood Education (ECE; n = 20) was used to form two distinct (i.e., PA/SB and ECE) panels for a 3-round Delphi study. In round 1, the PA/SB experts suggested their top 10 items for a Canadian childcare PA/SB policy. Policy items were then pooled to generate a list of 24 unique items. In round 2, experts in both panels rated the importance of the 24 policy items using a 7-point Likert scale (i.e., 1 = Not at all important to 7 = Extremely important). The ECE panel was also asked to report on the feasibility of the policy items using a 4-point Likert scale (i.e., 1 = Not at all feasible to 4 = Very feasible). Policy items that received an interquartile deviation (IQD) score of ≤ 1 (indicating consensus) and a median score of ≥ 6 (indicating importance) in both panels were considered shared priorities. In round 3, members of both panels re-rated the importance of the policy items that did not achieve consensus among their respective panel in round 2 and were asked to order items based on importance. Descriptive statistics were used to assess feasibility of policy items, and differences in panel ratings were quantified using Mann Whitney U tests. Consensus was achieved for 23 policy items in the PA/SB panel and 17 items in the ECE panel. Overall, 15 shared priorities were identified (e.g., provide 120 min of outdoor time per day, sedentary behaviour should not be used as a punishment), and six policy items exhibited a statistical difference in ratings across panels. Members of the ECE panel indicated that the policy item, "children should be permitted to go outside whenever they want, for as long as they want" (M = 1.78; SD = 0.65) was lowest in terms of feasibility, and the policy item, "children should receive opportunities to engage in both unstructured and structured physical activity opportunities daily" (M = 3.89; SD = 0.32) was the most feasible for daily implementation. Findings from this study can inform the development of an expert-generated and feasibility-informed institutional PA/SB policy for use in Canadian childcare settings. Supplementary Information: The online version contains supplementary material available at 10.1007/s10643-023-01473-z.

3.
Mass Spectrom Rev ; 40(5): 609-627, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-32770688

RESUMEN

Since the first mass spectrometry (MS) experiments were conducted by Thomson and Aston, plasmas have been used as ionization sources. Historically, plasma ion sources were used for these experiments because they were one of the few known sources of gas-phase ions at the time and they were relatively simple to setup and operate. Since then, developments in plasma ionization have continued to inform and motivate advances in other areas of MS. For example, plasma-desorption MS demonstrated ionization of large peptides and polymers more than 10 years before the first descriptions of electrospray ionization (ESI) and matrix-assisted laser desorption/ionization (MALDI). As a result, significant effort was placed on development of ionization approaches, mass analysis, and detection approaches for very large molecules: even before the advent of ESI and MALDI. Since then, new analytical challenges and opportunities in plasma ionization have arisen. In this review, the emerging trends in plasma-based ionization for several areas of MS will be discussed, including molecular ionization, elemental ionization, hybrid elemental and molecular ion sources, and unique chemical transformations. © 2020 John Wiley & Sons Ltd. Mass Spec Rev.

4.
Anal Chem ; 93(12): 5009-5014, 2021 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-33729743

RESUMEN

Concomitant species that appear at the same or very similar times in a mass-spectral analysis can clutter a spectrum because of the coexistence of many analyte-related ions (e.g., molecular ions, adducts, fragments). One method to extract ions stemming from the same origin is to exploit the chemical information encoded in the time domain, where the individual temporal appearances inside the complex structures of chronograms or chromatograms differ with respect to analytes. By grouping ions with very similar or identical time-domain structures, single-component mass spectra can be reconstructed, which are much easier to interpret and are library-searchable. While many other approaches address similar objectives through the Pearson's correlation coefficient, we explore an alternative method based on a modified cross-correlation algorithm to compute a metric that describes the degree of similarity between features inside any two ion chronograms. Furthermore, an automatic workflow was devised to be capable of categorizing thousands of mass-spectral peaks into different groups within a few seconds. This approach was tested with direct mass-spectrometric analyses as well as with a simple, fast, and poorly resolved LC-MS analysis. Single-component mass spectra were extracted in both cases and were identified based on accurate mass and a mass-spectral library search.

5.
Environ Sci Technol ; 55(13): 8484-8491, 2021 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-34101444

RESUMEN

The COVID-19 pandemic has given rise to rapid and widespread international pursuit of wastewater surveillance for genetic signals of SARS-CoV-2, the virus causing the pandemic. Environmental scientists and engineers familiar with the techniques required for this endeavor have responded. Many of the environmental scientists engaged in these investigations have not necessarily had experience with the ethical obligations associated with generating and handling human health data. The Canadian Water Network facilitated adoption of these surveillance methods by creating a national coalition, which included a public health advisory group that recognized a need for ethics guidance for the wastewater approach to public health surveillance. This Policy Analysis addresses that need and is based on a review of relevant ethics literature tightly focused on ethics applicable to public health surveillance. That review revealed that classical health bioethics governing clinical practice and general public health ethics guidance did not adequately address key issues in wastewater surveillance. The 2017 World Health Organization guidelines, directly based on a systematic literature review, specifically addressed ethical issues in public health surveillance. The application of relevant ethical guidance to wastewater surveillance is analyzed and summarized for environmental scientists.


Asunto(s)
COVID-19 , Pandemias , Canadá , Humanos , SARS-CoV-2 , Aguas Residuales
6.
Biochemistry ; 59(37): 3438-3446, 2020 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-32833433

RESUMEN

Although allosteric binding of small molecules is commonplace in protein structures, it is rather rare in DNA species such as G-quadruplexes. By using CD melting, here, we found binding of the small-molecule ligands PDS and L2H2-6OTD to the telomeric DNA G-quadruplex was cooperative. Mass spectrometry indicated a 1:1:1 ratio in the ternary binding complex of the telomeric G-quadruplex, PDS, and L2H2-6OTD. Compared to the binding of each individual ligand to the G-quadruplex, single-molecule mechanical unfolding assays revealed a significantly decreased dissociation constant when one ligand is evaluated in the presence of another. This demonstrates that cooperative binding of PDS and L2H2-6OTD to the G-quadruplex is allosteric, which is also supported by the mass spectra data that indicated the ejection of coordinated sodium ions upon binding of the heteroligands to the G-quadruplex. The unprecedented observation of the allosteric ligand binding to higher-ordered structures of DNA may help to design more effective ligands to target non-B DNA species involved in many critical cellular processes.


Asunto(s)
Aminoquinolinas/metabolismo , G-Cuádruplex , Oxazoles/metabolismo , Ácidos Picolínicos/metabolismo , Telómero/química , Telómero/metabolismo , Sitio Alostérico , Sitios de Unión , Humanos , Ligandos , Modelos Moleculares
7.
Int J Behav Nutr Phys Act ; 17(1): 74, 2020 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-32539730

RESUMEN

BACKGROUND: Children and youth who meet the physical activity, sedentary, and sleep behaviour recommendations in the Canadian 24-Hour Movement Guidelines are more likely to have desirable physical and psychosocial health outcomes. Yet, few children and youth actually meet the recommendations. The family is a key source of influence that can affect lifestyle behaviours. The purpose of this paper is to describe the process used to develop the Consensus Statement on the Role of the Family in the Physical Activity, Sedentary, and Sleep Behaviours of Children and Youth (0-17 years) and present, explain, substantiate, and discuss the final Consensus Statement. METHODS: The development of the Consensus Statement included the establishment of a multidisciplinary Expert Panel, completion of six reviews (three literature, two scoping, one systematic review of reviews), custom data analyses of Statistics Canada's Canadian Health Measures Survey, integration of related research identified by Expert Panel members, a stakeholder consultation, establishment of consensus, and the development of a media, public relations, communications and launch plan. RESULTS: Evidence from the literature reviews provided substantial support for the importance of family on children's movement behaviours and highlighted the importance of inclusion of the entire family system as a source of influence and promotion of healthy child and youth movement behaviours. The Expert Panel incorporated the collective evidence from all reviews, the custom analyses, other related research identified, and stakeholder survey feedback, to develop a conceptual model and arrive at the Consensus Statement: Families can support children and youth in achieving healthy physical activity, sedentary and sleep behaviours by encouraging, facilitating, modelling, setting expectations and engaging in healthy movement behaviours with them. Other sources of influence are important (e.g., child care, school, health care, community, governments) and can support families in this pursuit. CONCLUSION: Family is important for the support and promotion of healthy movement behaviours of children and youth. This Consensus Statement serves as a comprehensive, credible, and current synopsis of related evidence, recommendations, and resources for multiple stakeholders.


Asunto(s)
Ejercicio Físico/fisiología , Familia , Conducta Sedentaria , Sueño/fisiología , Adolescente , Canadá , Niño , Preescolar , Consenso , Humanos , Lactante , Recién Nacido
8.
Anal Bioanal Chem ; 410(17): 4061-4076, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29700557

RESUMEN

In this article, some recent trends and developments in ambient desorption/ionization mass spectrometry (ADI-MS) are reviewed, with a special focus on quantitative analyses with direct, open-air sampling. Accurate quantification with ADI-MS is still not routinely performed, but this aspect is considered of utmost importance for the advancement of the field. In fact, several research groups are devoted to the development of novel and optimized ADI-MS approaches. Some key trends include novel sample introduction strategies for improved reproducibility, tailored sample preparation protocols for removing the matrix and matrix effects, and multimode ionization sources. In addition, there is significant interest in quantitative mass spectrometry imaging. Graphical abstract Conceptual diagram of the ambient desorption/ionization mass spectrometry approach with different desorption/ionization probes.

9.
Anal Chem ; 88(7): 3494-503, 2016 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-26916720

RESUMEN

Plasma-based ambient desorption/ionization sources are versatile in that they enable direct ionization of gaseous samples as well as desorption/ionization of analytes from liquid and solid samples. However, ionization matrix effects, caused by competitive ionization processes, can worsen sensitivity or even inhibit detection all together. The present study is focused on expanding the analytical capabilities of the flowing atmospheric-pressure afterglow (FAPA) source by exploring additional types of ionization chemistry. Specifically, it was found that the abundance and type of reagent ions produced by the FAPA source and, thus, the corresponding ionization pathways of analytes, can be altered by changing the source working conditions. High abundance of proton-transfer reagent ions was observed with relatively high gas flow rates and low discharge currents. Conversely, charge-transfer reagent species were most abundant at low gas flows and high discharge currents. A rather nonpolar model analyte, biphenyl, was found to significantly change ionization pathway based on source operating parameters. Different analyte ions (e.g., MH(+) via proton-transfer and M(+.) via charge-transfer) were formed under unique operating parameters demonstrating two different operating regimes. These tunable ionization modes of the FAPA were used to enable or enhance detection of analytes which traditionally exhibit low-sensitivity in plasma-based ADI-MS analyses. In one example, 2,2'-dichloroquaterphenyl was detected under charge-transfer FAPA conditions, which were difficult or impossible to detect with proton-transfer FAPA or direct analysis in real-time (DART). Overall, this unique mode of operation increases the number and range of detectable analytes and has the potential to lessen ionization matrix effects in ADI-MS analyses.

10.
Chemistry ; 21(17): 6409-19, 2015 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-25760981

RESUMEN

The reactions of the carbonate radical anion (CO3 (.) (-) ) with vitamin B12 derivatives were studied by pulse radiolysis. The carbonate radical anion directly oxidizes the metal center of cob(II)alamin quantitively to give hydroxycobalamin, with a bimolecular rate constant of 2.0×10(9) M(-1) s(-1) . The reaction of CO3 (.) (-) with hydroxycobalamin proceeds in two steps. The second-order rate constant for the first reaction is 4.3×10(8) M(-1) s(-1) . The rate of the second reaction is independent of the hydroxycobalamin concentration and is approximately 3.0×10(3) s(-1) . Evidence for formation of corrinoid complexes differing from cobalamin by the abstraction of two or four hydrogen atoms from the corrin macrocycle and lactone ring formation has been obtained by ultra-high-performance liquid chromatography/high-resolution mass spectrometry (UHPLC/HRMS). A mechanism is proposed in which abstraction of a hydrogen atom by CO3 (.) (-) from a carbon atom not involved in the π conjugation system of the corrin occurs in the first step, resulting in formation of a Co(III) C-centered radical that undergoes rapid intramolecular electron transfer to form the corresponding Co(II) carbocation complex for about 50 % of these complexes. Subsequent competing pathways lead to formation of corrinoid complexes with two fewer hydrogen atoms and lactone derivatives of B12 . Our results demonstrate the potential of UHPLC combined with HRMS in the separation and identification of tetrapyrrole macrocycles with minor modifications from their parent molecule.


Asunto(s)
Vitamina B 12/análogos & derivados , Vitamina B 12/química , Carbonatos/química , Cromatografía Liquida , Compuestos Macrocíclicos/química , Espectrometría de Masas , Estructura Molecular , Radiólisis de Impulso
11.
Inorg Chem ; 54(14): 6873-84, 2015 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-26113440

RESUMEN

Reactions between 2,6-diformyl-4-alkyl(R)-phenol (R = CH3 or C(CH3)3) and 1,3-diamino-2-hydroxypropane (1,3-DAP) in the presence of copper(II) salts (Cu(BF4)2·6H2O, Cu(ClO4)2·6H2O/H3BO3/Ar) and triethylamine (TEA) in a single pot result in self-assembly of dimeric dodecacopper supramolecular architectures of 30-membered hexatopic macrocyclic ligands (H6L4 and H6L5) with unique and fascinating structures having the BO3(3-) anion as the central species bonded to all six copper centers in a symmetrical fashion (µ6-BO3(3-)). A number of closely related macrocyclic hexacopper complexes are reported: {[Cu6(L4)(µ6-BO3)(µ-H2O)(C3H7NO)2(BF4)][BF4]2·3C3H7NO}2 (1) (DMF = C3H7NO), {[Cu6(L4)(µ6-BO3)(µ-C3H7NO)3][ClO4]3·3C3H7NO}2 (2), {[Cu6(L5)(µ6-BO3)(µ-OH)(H2O)3(C3H7NO)][BF4]2·6C3H7NO·4C2H5OH·2H2O}2 (3), {[Cu6(L5)(µ6-BO3)(µ-CH3OH)(CH3OH)2][ClO4]3·10H2O}2 (4), and {[Cu6(L5)(µ6-BO3)(µ-CH3CO2)(µ-CH3O)(CH3OH)][BF4]·13CH3OH·8H2O}2 (5). A polymeric side product {[Cu2(H2L2)(CH3OH)(BF4)][BF4]}n (6), involving a 2 + 2 macrocyclic ligand, was also isolated and structurally characterized. Complex 6 involves dinuclear copper(II) units linked through BF4(-) anions to form a novel 1D single-chain polymeric coordination compound. This appears to be the first report in which a central BO3(3-) species is linked to six copper(II) ions held together by a single macrocyclic ligand through three µ1,1-O(BO3(3-)) and three µ1,3-O(BO3(3-)) bridges. In complexes 1-5 the BO3(3-) is present in the center of the macrocyclic cavity and is bonded to all six metal centers arranged in a benzene-like hexagonal array. In the hexagonal array there are alternate double (µ-alkoxide and µ1,3-O(BO3(3-))) and (µ-phenoxide and µ1,1-O(BO3(3-))) bridges between the Cu(II) centers. The symmetrical hexa-bridging nature of µ6-BO3(3-) is unprecedented in transition metal complex chemistry, and along with alkoxide and phenoxide bridges in the equatorial plane provides effective pathways for an overall antiferromagnetic exchange interaction between six copper(II) centers. In 1, 3, and 5 the BO3(3-) moiety is produced in one step (synthetic) by an unusual copper(II)-macrocycle complex catalyzed hydrolysis of BF4(-) ion in methanol. In 2 and 4 the central species (BO3(3-)) comes from boric acid (H3BO3) which is added to reaction mixture of Cu(ClO4)2/H6L4/H6L5 under inert conditions to confirm the identity of the central species.


Asunto(s)
Compuestos de Boro/química , Complejos de Coordinación/química , Cobre/química , Compuestos Macrocíclicos/química , Imanes/química , Cristalografía por Rayos X , Dimerización , Ligandos , Modelos Moleculares
13.
Anal Chem ; 86(6): 2900-8, 2014 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-24521448

RESUMEN

A major design objective of portable mass spectrometers is the ability to perform in situ chemical analysis on target samples in their native states in the undisturbed environment. The miniature instrument described here is fully contained in a wearable backpack (10 kg) with a geometry-independent low-temperature plasma (LTP) ion source integrated into a hand-held head unit (2 kg) to allow direct surface sampling and analysis. Detection of chemical warfare agent (CWA) simulants, illicit drugs, and explosives is demonstrated at nanogram levels directly from surfaces in near real time including those that have complex geometries, those that are heat-sensitive, and those bearing complex sample matrices. The instrument consumes an average of 65 W of power and can be operated autonomously under battery power for ca. 1.5 h, including the initial pump-down of the manifold. The maximum mass-to-charge ratio is 925 Th with mass resolution of 1-2 amu full width at half-maximun (fwhm) across the mass range. Multiple stages of tandem analysis can be performed to identify individual compounds in complex mixtures. Both positive and negative ion modes are available. A graphical user interface (GUI) is available for novice users to facilitate data acquisition and real-time spectral matching.


Asunto(s)
Espectrometría de Masas/métodos , Miniaturización , Programas Informáticos , Interfaz Usuario-Computador
14.
Anal Bioanal Chem ; 406(25): 6111-27, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25069879

RESUMEN

Ambient desorption/ionization mass spectrometry (ADI-MS) aims to enable direct analysis of gaseous, liquid, and/or solid samples under ambient conditions. In ADI-MS, different types of desorption/ionization sources are classified according to their basic method of operation, namely spray-based, laser-based, or plasma-based. This review discusses many of the plasma-based techniques coupled to mass spectrometry in terms of their current performance in fast qualitative screening and quantitative analysis. Critical aspects, for example sample preparation and introduction, quantification, and matrix effects, are addressed. Furthermore, the applicability of plasma-based sources to portable mass spectrometers and their capabilities in imaging experiments are summarized. The applications discussed are of two types. In one, direct screening is performed without any or with minimal sample pretreatment. Samples with low matrix content are qualitatively analyzed without interferences. The other, more challenging applications, namely samples with high matrix content and most quantitative analysis, typically require sample preparation ranging from simple dilution to extensive multi-step procedures.

15.
JMIR Public Health Surveill ; 10: e47154, 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38788212

RESUMEN

BACKGROUND: The COVID-19 pandemic has prompted the deployment of digital technologies for public health surveillance globally. The rapid development and use of these technologies have curtailed opportunities to fully consider their potential impacts (eg, for human rights, civil liberties, privacy, and marginalization of vulnerable groups). OBJECTIVE: We conducted a scoping review of peer-reviewed and gray literature to identify the types and applications of digital technologies used for surveillance during the COVID-19 pandemic and the predicted and witnessed consequences of digital surveillance. METHODS: Our methodology was informed by the 5-stage methodological framework to guide scoping reviews: identifying the research question; identifying relevant studies; study selection; charting the data; and collating, summarizing, and reporting the findings. We conducted a search of peer-reviewed and gray literature published between December 1, 2019, and December 31, 2020. We focused on the first year of the pandemic to provide a snapshot of the questions, concerns, findings, and discussions emerging from peer-reviewed and gray literature during this pivotal first year of the pandemic. Our review followed the PRISMA-ScR (Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews) reporting guidelines. RESULTS: We reviewed a total of 147 peer-reviewed and 79 gray literature publications. Based on our analysis of these publications, we identified a total of 90 countries and regions where digital technologies were used for public health surveillance during the COVID-19 pandemic. Some of the most frequently used technologies included mobile phone apps, location-tracking technologies, drones, temperature-scanning technologies, and wearable devices. We also found that the literature raised concerns regarding the implications of digital surveillance in relation to data security and privacy, function creep and mission creep, private sector involvement in surveillance, human rights, civil liberties, and impacts on marginalized groups. Finally, we identified recommendations for ethical digital technology design and use, including proportionality, transparency, purpose limitation, protecting privacy and security, and accountability. CONCLUSIONS: A wide range of digital technologies was used worldwide to support public health surveillance during the COVID-19 pandemic. The findings of our analysis highlight the importance of considering short- and long-term consequences of digital surveillance not only during the COVID-19 pandemic but also for future public health crises. These findings also demonstrate the ways in which digital surveillance has rendered visible the shifting and blurred boundaries between public health surveillance and other forms of surveillance, particularly given the ubiquitous nature of digital surveillance. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR2-https://doi.org/10.1136/bmjopen-2021-053962.


Asunto(s)
COVID-19 , Tecnología Digital , Pandemias , COVID-19/epidemiología , COVID-19/prevención & control , Humanos , Pandemias/prevención & control , Vigilancia en Salud Pública/métodos
16.
Can J Public Health ; 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38739320

RESUMEN

OBJECTIVE: To systematically assess the Canadian federal government's current alcohol policies in relation to public health best practices. METHODS: The 2022 Canadian Alcohol Policy Evaluation (CAPE) Project assessed federal alcohol policies across 10 domains. Policy domains were weighted according to evidence for their relative impact, including effectiveness and scope. A detailed scoring rubric of best practices was developed and externally reviewed by international experts. Policy data were collected between June and December 2022, using official legislation, government websites, and data sources identified from previous iterations of CAPE as sources. Contacts within relevant government departments provided any additional data sources, reviewed the accuracy and completeness of the data, and provided amendments as needed. Data were scored independently by members of the research team. Final policy scores were tabulated and presented as a weighted overall average score and as unweighted domain-specific scores. RESULTS: Compared to public health best practices, the federal government of Canada scored 37% overall. The three most impactful domains-(1) pricing and taxation, (2) marketing and advertising controls, and (3) impaired driving countermeasures-received some of the lowest scores (39%, 10%, and 40%, respectively). Domain-specific scores varied considerably from 0% for minimum legal age policies to 100% for controls on physical availability of alcohol. CONCLUSION: Many evidence-informed alcohol policies have not been adopted, or been adopted only partially, by the Canadian federal government. Urgent adoption of the recommended policies is needed to prevent and reduce the enormous health, social, and economic costs of alcohol use in Canada.


RéSUMé: OBJECTIF: Évaluer de manière systématique les politiques sur l'alcool actuelles du gouvernement fédéral canadien dans le cadre de pratiques de santé publique exemplaires. MéTHODES: Le projet de l'Évaluation des politiques canadiennes sur l'alcool 2022 a évalué les politiques fédérales sur l'alcool dans dix domaines. Ces domaines de politiques ont été pondérés en fonction de preuves sur leurs répercussions relatives, notamment leur efficacité et leur portée. Une échelle d'évaluation descriptive détaillée de pratiques exemplaires a été élaborée et examinée à l'externe. Entre juin et décembre 2022, des données sur les politiques ont été recueillies dans la législation officielle, sur des sites Web du gouvernement et au moyen de sources identifiées comme telles au cours des itérations précédentes du projet de l'Évaluation des politiques canadiennes sur l'alcool. Des personnes-ressources au sein des ministères concernés ont communiqué d'autres sources de données, examiné l'exactitude et le caractère exhaustif de ces données et apporté les modifications nécessaires. Les données ont été évaluées indépendamment par des membres de l'équipe de recherche. Les scores de politiques finaux ont été inscrits dans des tableaux et présentés sous forme d'une moyenne générale pondérée et de scores non pondérés par domaine. RéSULTATS: Comparativement aux pratiques de santé publique exemplaire, le gouvernement fédéral du Canada a obtenu un score général de 37 %. Les trois domaines susceptibles d'avoir les plus grandes répercussions, à savoir 1) la fixation des prix et la taxation, 2) le contrôle du marketing et de la publicité, et 3) les mesures contre la conduite avec facultés affaiblies, se sont vu attribuer parmi les scores les plus bas (39 %, 10 %, et 40 % respectivement). Les scores par domaine variaient considérablement, allant de 0 % pour les politiques sur l'âge minimum légal à 100 % pour le contrôle de la disponibilité physique de l'alcool. CONCLUSION: De nombreuses politiques sur l'alcool reposant sur des preuves n'ont pas été adoptées, ou l'ont été seulement partiellement, par le gouvernement fédéral canadien. Il est urgent d'appliquer les politiques recommandées pour prévenir et réduire les énormes coûts sanitaires, sociaux et économiques de la consommation d'alcool au Canada.

17.
Anal Chem ; 85(14): 6545-52, 2013 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-23721516

RESUMEN

We describe a handheld, wireless low-temperature plasma (LTP) ambient ionization source and its performance on a benchtop and a miniature mass spectrometer. The source, which is inexpensive to build and operate, is battery-powered and utilizes miniature helium cylinders or air as the discharge gas. Comparison of a conventional, large-scale LTP source against the handheld LTP source, which uses less helium and power than the large-scale version, revealed that the handheld source had similar or slightly better analytical performance. Another advantage of the handheld LTP source is the ability to quickly interrogate a gaseous, liquid, or solid sample without requiring any setup time. A small, 7.4-V Li-polymer battery is able to sustain plasma for 2 h continuously, while the miniature helium cylinder supplies gas flow for approximately 8 continuous hours. Long-distance ion transfer was achieved for distances up to 1 m.

18.
Anal Chem ; 85(15): 7512-8, 2013 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-23808829

RESUMEN

The flowing atmospheric-pressure afterglow (FAPA) is a promising new source for atmospheric-pressure, ambient desorption/ionization mass spectrometry. However, problems exist with reproducible sample introduction into the FAPA source. To overcome this limitation, a new FAPA geometry has been developed in which concentric tubular electrodes are utilized to form a halo-shaped discharge; this geometry has been termed the halo-FAPA or h-FAPA. With this new geometry, it is still possible to achieve direct desorption and ionization from a surface; however, sample introduction through the inner capillary is also possible and improves interaction between the sample material (solution, vapor, or aerosol) and the plasma to promote desorption and ionization. The h-FAPA operates with a helium gas flow of 0.60 L/min outer, 0.30 L/min inner, and applied current of 30 mA at 200 V for 6 W of power. In addition, separation of the discharge proper and sample material prevents perturbations to the plasma. Optical-emission characterization and gas rotational temperatures reveal that the temperature of the discharge is not significantly affected (<3% change at 450 K) by water vapor during solution-aerosol sample introduction. The primary mass-spectral background species are protonated water clusters, and the primary analyte ions are protonated molecular ions (M + H(+)). Flexibility of the new ambient sampling source is demonstrated by coupling it with a laser ablation unit, a concentric nebulizer, and a droplet-on-demand system for sample introduction. A novel arrangement is also presented in which the central channel of the h-FAPA is used as the inlet to a mass spectrometer.


Asunto(s)
Presión Atmosférica , Espectrometría de Masas/instrumentación , Conductividad Eléctrica , Diseño de Equipo , Preparaciones Farmacéuticas/química
19.
Rapid Commun Mass Spectrom ; 27(1): 135-42, 2013 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-23239326

RESUMEN

RATIONALE: This paper reports the development of arrays of capillary-based low-temperature plasma (LTP) probes for direct sample analysis. These probe arrays allow a higher surface area to be analyzed, increasing the throughput in large sample analysis. Validation of these arrays was performed on illicit, cathinone-based drugs marketed as 'bath salts'. METHODS: LTP arrays consisting of 1, 7, and 19 probes were constructed with quartz capillaries and held together with silver epoxy resin adhesive. Three drugs, mephedrone, methylone and methylenedioxypyrovalerone, were analyzed with each plasma ion source and an ion trap mass spectrometer in full MS and in MS/MS positive ion mode. Chemical and thermal footprints were determined for each source. A reactive probe design was used to inject trifluoroacetic anhydride directly into the plasma stream for on-line derivatization. RESULTS: Small LTP probes and bundled arrays provide low picogram level limits of detection for mephedrone, methylone and methylenedioxypyrovalerone. Bundling the probes together in larger arrays increases the surface area analyzed by a factor of ten, while maintaining surface temperatures below 40 °C. Selectivity towards mephedrone and methylone was increased using trifluoracetylation under ambient ionization conditions. CONCLUSIONS: Low-temperature plasma ionization sources allow rapid detection of illicit 'bath salt' drugs in low amounts. The sources have a larger sampling area that allows faster detection of each analyte, and selectivity towards the selected drug is enhanced by adding reagents directly into the plasma stream.


Asunto(s)
Espectrometría de Masas/métodos , Gases em Plasma/química , Benzodioxoles/análisis , Benzodioxoles/química , Frío , Drogas Ilícitas/análisis , Drogas Ilícitas/química , Límite de Detección , Espectrometría de Masas/instrumentación , Metanfetamina/análogos & derivados , Metanfetamina/análisis , Metanfetamina/química , Modelos Químicos , Pirrolidinas/análisis , Pirrolidinas/química , Reproducibilidad de los Resultados , Cathinona Sintética
20.
Syst Rev ; 12(1): 31, 2023 03 06.
Artículo en Inglés | MEDLINE | ID: mdl-36879324

RESUMEN

BACKGROUND: Virtual care is transforming the nature of healthcare, particularly with the accelerated shift to telehealth and virtual care during the COVID-19 pandemic. Health profession regulators face intense pressures to safely facilitate this type of healthcare while upholding their legislative mandate to protect the public. Challenges for health profession regulators have included providing practice guidance for virtual care, changing entry-to-practice requirements to include digital competencies, facilitating interjurisdictional virtual care through licensure and liability insurance requirements, and adapting disciplinary procedures. This scoping review will examine the literature on how the public interest is protected when regulating health professionals providing virtual care. METHODS: This review will follow the Joanna Briggs Institute (JBI) scoping review methodology. Academic and grey literature will be retrieved from health sciences, social sciences, and legal databases using a comprehensive search strategy underpinned by Population-Concept-Context (PCC) inclusion criteria. Articles published in English since January 2015 will be considered for inclusion. Two reviewers will independently screen titles and abstracts and full-text sources against specific inclusion and exclusion criteria. Discrepancies will be resolved through discussion or by a third reviewer. One research team member will extract relevant data from the selected documents and a second will validate the extractions. DISCUSSION: Results will be presented in a descriptive synthesis that highlights implications for regulatory policy and professional practice, as well as study limitations and knowledge gaps that warrant further research. Given the rapid expansion of virtual care provision by regulated health professionals in response to the COVID-19 pandemic, mapping the literature on how the public interest is protected in this rapidly evolving digital health sector may help inform future regulatory reform and innovation. SYSTEMATIC REVIEW REGISTRATION: This protocol is registered with the Open Science Framework ( https://doi.org/10.17605/OSF.IO/BD2ZX ).


Asunto(s)
COVID-19 , Pandemias , Humanos , Pandemias/prevención & control , COVID-19/prevención & control , Personal de Salud , Bases de Datos Factuales , Literatura Gris , Literatura de Revisión como Asunto
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