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1.
Compr Rev Food Sci Food Saf ; 23(4): e13387, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38865237

RESUMO

Over recent years, there has been an increase in the number of reported cases of food fraud incidents, whereas at the same time, consumers demand authentic products of high quality. The emerging volatilomics technology could be the key to the analysis and characterization of the quality of different foodstuffs. This field of omics has aroused the interest of scientists due to its noninvasive, rapid, and cost-profitable nature. This review aims to monitor the available scientific information on the use of volatilomics technology, correlate it to the relevant food categories, and demonstrate its importance in the food adulteration, authenticity, and origin areas. A comprehensive literature search was performed using various scientific search engines and "volatilomics," "volatiles," "food authenticity," "adulteration," "origin," "fingerprint," "chemometrics," and variations thereof as keywords, without chronological restriction. One hundred thirty-seven relevant publications were retrieved, covering 11 different food categories (meat and meat products, fruits and fruit products, honey, coffee, tea, herbal products, olive oil, dairy products, spices, cereals, and others), the majority of which focused on the food geographical origin. The findings show that volatilomics typically involves various methods responsible for the extraction and consequential identification of volatile compounds, whereas, with the aid of data analysis, it can handle large amounts of data, enabling the origin classification of samples or even the detection of adulteration practices. Nonetheless, a greater number of specific research studies are needed to unlock the full potential of volatilomics.


Assuntos
Contaminação de Alimentos , Contaminação de Alimentos/análise , Compostos Orgânicos Voláteis/análise , Análise de Alimentos/métodos
2.
Phytochem Anal ; 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38860343

RESUMO

INTRODUCTION: Winegrape varieties Kotsifali, Limnio, and Vradiano OBJECTIVE: The aim of this study was to develop a liquid chromatographic quadrupole time-of-flight tandem mass spectrometric (LC-QTOF-MS/MS) method for the investigation of the anthocyanin and proanthocyanidin content of Greek grape varieties employing target and suspect screening strategies. METHODOLOGY: A novel LC-QTOF-MS/MS method was developed and validated to assess the anthocyanin content of Kotsifali, Limnio, and Vradiano grape varieties. Sixteen grape samples were collected from the main growing areas of each variety in Greece. The influence of the grape variety on the anthocyanin and proanthocyanidin composition of three Greek winegrapes was investigated using chemometrics. RESULTS: Excellent linearity (R2 > 0.99) was achieved for all the target analytes, and recoveries ranged between 90.1% and 119.1%. The limits of quantification (LOQs) and limits of detection (LODs) were calculated over the range of 0.020-0.40 mg/g and 0.010-0.13 mg/g, respectively. The RSD% was lower than 9.1% and 7.3% for intra-day and inter-day studies, respectively, indicating satisfactory trueness and precision. Target and suspect screening resulted in the identification of 5 and 26 anthocyanins, respectively. CONCLUSIONS: Kotsifali variety exhibited a higher concentration of anthocyanins compared with Vradiano and Limnio. Higher levels of mean degree of polymerization (mDp) and different percentage levels of prodelphinidins (%P) were established among the varieties.

3.
Heliyon ; 10(11): e31467, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38882372

RESUMO

Currently, there is fierce competition in the cocoa industry to develop products that possess distinctive sensory characteristics and flavours. This is because cocoa and its derivatives provide numerous health and functional advantages, which is essential to their economics. The fatty acid and triglyceride composition of cocoa determines its quality. This review emphasises the necessity of developing precise, adaptable analytical techniques to identify and quantify cocoa butter in cocoa and its derived products, from cocoa beans to chocolate bars. Key chromatographic and spectroscopic techniques play crucial roles in understanding the fundamental principles underlying the production of cocoa with desirable flavours. This significantly impacts the sustainability, traceability, and authenticity of cocoa products while also supporting the battle against adulteration.

4.
Food Chem ; 456: 140070, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38917694

RESUMO

Food adulteration and illegal supplementations have always been one of the major problems in the world. The threat of food adulteration to the health of consumers cannot be ignored. Food of questionable origin causes economic losses to consumers, but the potential health risks cannot be ignored. However, the traditional detection methods are time-consuming and complex. This review mainly discusses the types of adulteration and technologies used to detect adulteration. Matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS) is also emphasized in the detection of adulteration and authenticity of origin analysis of various types of food (milk, meat, edible oil, etc.), and the future application direction and feasibility of this technology are analyzed. On this basis, MALDI-TOF MS was compared with other detection methods, highlighting the advantages of this technology in the detection of food adulteration. The future development prospect and direction of this technology are also emphasized.

5.
Sci Rep ; 14(1): 13342, 2024 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858425

RESUMO

Yemeni smallholder coffee farmers face several challenges, including the ongoing civil conflict, limited rainfall levels for irrigation, and a lack of post-harvest processing infrastructure. Decades of political instability have affected the quality, accessibility, and reputation of Yemeni coffee beans. Despite these challenges, Yemeni coffee is highly valued for its unique flavor profile and is considered one of the most valuable coffees in the world. Due to its exclusive nature and perceived value, it is also a prime target for food fraud and adulteration. This is the first study to identify the potential of Near Infrared Spectroscopy and chemometrics-more specifically, the discriminant analysis (PCA-LDA)-as a promising, fast, and cost-effective tool for the traceability of Yemeni coffee and sustainability of the Yemeni coffee sector. The NIR spectral signatures of whole green coffee beans from Yemeni regions (n = 124; Al Mahwit, Dhamar, Ibb, Sa'dah, and Sana'a) and other origins (n = 97) were discriminated with accuracy, sensitivity, and specificity ≥ 98% using PCA-LDA models. These results show that the chemical composition of green coffee and other factors captured on the spectral signatures can influence the discrimination of the geographical origin, a crucial component of coffee valuation in the international markets.


Assuntos
Coffea , Espectroscopia de Luz Próxima ao Infravermelho , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Coffea/química , Análise Discriminante , Café/química , Sementes/química
6.
Front Psychol ; 15: 1231484, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38939224

RESUMO

An emerging body of research attends to grasp the concept of authenticity. Nonetheless, a view on the developmental part with its underlying facets of Inner Work processes, is rare. In this paper, we aim to take a deeper look into the dynamics of inner work processes, that define certain authenticity developmental stages. Building upon our recently proposed "4C-view" of authenticity, we approach this developmental perspective from two different angles: from a process characteristic angle and a developmental level angle. Using vignettes of authentic client personality coaching processes, we propose that the interwoven dynamic between those two aspects yields several combinations of maturity levels within the individual. Continuity as an overarching concept thus contains various developmental authenticity stages that could be identified through different markers and vary in particular contexts.

7.
Front Psychol ; 15: 1291650, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38708019

RESUMO

This work expands the existing understanding of quality assessments of VR experiences. Historically, VR quality has focused on presence and immersion, but current discourse emphasizes plausibility and believability as critical for lifelike, credible VR. However, the two concepts are often conflated, leading to confusion. This paper proposes viewing them as subsets of authenticity and presents a structured hierarchy delineating their differences and connections. Additionally, coherence and congruence are presented as complementary quality functions that integrate internal and external logic. The paper considers quality formation in the experience of authenticity inside VR emphasizing that distinguishing authenticity in terms of precise quality features are essential for accurate assessments. Evaluating quality requires a holistic approach across perceptual, cognitive, and emotional factors. This model provides theoretical grounding for assessing the quality of VR experiences.

8.
Phytomedicine ; 129: 155667, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38728918

RESUMO

BACKGROUND: It has been a current research hospots using fingerprinting technology for quality control of Chinese herbal medicines (CHMs), which provides a scientific basis for establishment of overall quality control in accordance with the characteristics of CHMs. The fingerprinting technology for CHMs is diverse, and the research field covers many disciplines, such as analytical chemistry, pharmacology, pharmaceutics, biochemistry, and molecular biology. PURPOSE: To effectively understand the key areas and future directions of research regarding the fingerprint and adulteration of CHMs. METHODS/RESULTS: this paper analyzed 879 articles in this field in the Web of Science Core Collection from 2000 to 2023 with CiteSpace and VOSviewer, and systematically assessed the research process, hotspots, topic distribution among disciplines, etc. The most prominent contributors of fingerprint and adulteration of CHMs research are mainly from China, India, the United States, England, and Brazil. The knowledge domains of fingerprint and adulteration of CHMs research focus mainly on the topics of molecular authentication, DNA barcoding, HPLC, near-infrared spectroscopy, manage data, chemometrics, and electrochemical fingerprinting. Most countries have recognized the pharmaceutical potential of natural products, and have paid more attention to the fingerprint and adulteration of CHMs in the past decade. Future the research tends to focus more on molecular identification and authentication, and electrochemical and chromatographic fingerprinting in controlling the adulteration of CHMs. CONCLUSION: This research provides a valuable reference for scholars in related fields to analyze existing research results, understand the development trend, and explore new research directions.


Assuntos
Contaminação de Medicamentos , Medicamentos de Ervas Chinesas , Controle de Qualidade , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/análise , Cromatografia Líquida de Alta Pressão/métodos , Código de Barras de DNA Taxonômico
9.
Appetite ; 199: 107401, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38734375

RESUMO

Cultured meat is a promising substitute for regular meat, but its introduction faces challenges and expected consumer resistance. While some studies investigate how communication strategies and advertising appeals can address these concerns, the role of social media influencers in promoting cultured meat adoption remains yet to be explored. Across two online experimental studies involving 752 participants recruited from Prolific, this research investigates how influencer type (micro- vs. mega-influencer) affects consumers' willingness to buy cultured meat. Study 1 reveals that consumers are more willing to buy cultured meat when it is endorsed by micro- rather than mega-influencers. Further, perceived endorsement authenticity mediates this effect such that micro-influencers endorsements are perceived as more authentic than those of mega-influencers. Study 2 demonstrates that these effects are moderated by influencer expertise and type of meat, where micro-influencers with health (but not fashion) expertise have a more pronounced impact on increasing willingness to purchase cultured meat (but not regular meat). This research provides theoretical insights into how consumers perceive influencer endorsements for cultured meat. These findings aim to enhance consumer acceptance of cultured meat while offering actionable guidance for practitioners on promoting cultured meat brands on social media.


Assuntos
Comportamento do Consumidor , Mídias Sociais , Humanos , Masculino , Adulto , Feminino , Pessoa de Meia-Idade , Adulto Jovem , Carne , Preferências Alimentares/psicologia , Adolescente , Comportamento de Escolha , Carne in vitro
10.
Food Chem ; 453: 139560, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-38761721

RESUMO

Baijiu authenticity has been a frequent problem driven by economic interests in recent years, so it is important to discriminate against baijiu with different origins. Herein, we proposed a simple and efficient esters-targeted colorimetric sensor array mediated by hydroxylamine hydrochloride. Esters undergo a nucleophilic addition reaction with hydroxylamine hydrochloride to form hydroxamic acid, which rapidly forms a purplish red ferric hydroxamate under FeCl3·6H2O. Bromophenol blue and rhodamine B enrich the color effects. The array detected 12 esters with a detection limit on the order of 10-5 of most esters and 16 mixed esters with R2 > 0.999 and recoveries close to 100%. Otherwise, for discriminating 34 strong-aroma baijius (SABs), the array has an accuracy of 98% according to the origin, and 95% according to the grades, with a response time of 1 min. This study provides a new strategy for authenticity determination and quality control of baijiu.


Assuntos
Colorimetria , Ésteres , Colorimetria/instrumentação , Colorimetria/métodos , Ésteres/química , Ésteres/análise , Bebidas Alcoólicas/análise , Odorantes/análise
11.
Camb Q Healthc Ethics ; : 1-14, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38602092

RESUMO

The ongoing debate within neuroethics concerning the degree to which neuromodulation such as deep brain stimulation (DBS) changes the personality, identity, and agency (PIA) of patients has paid relatively little attention to the perspectives of prospective patients. Even less attention has been given to pediatric populations. To understand patients' views about identity changes due to DBS in obsessive-compulsive disorder (OCD), the authors conducted and analyzed semistructured interviews with adolescent patients with OCD and their parents/caregivers. Patients were asked about projected impacts to PIA generally due to DBS. All patient respondents and half of caregivers reported that DBS would impact patient self-identity in significant ways. For example, many patients expressed how DBS could positively impact identity by allowing them to explore their identities free from OCD. Others voiced concerns that DBS-related resolution of OCD might negatively impact patient agency and authenticity. Half of patients expressed that DBS may positively facilitate social access through relieving symptoms, while half indicated that DBS could increase social stigma. These views give insights into how to approach decision-making and informed consent if DBS for OCD becomes available for adolescents. They also offer insights into adolescent experiences of disability identity and "normalcy" in the context of OCD.

12.
Anal Chim Acta ; 1304: 342555, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38637039

RESUMO

BACKGROUND: Omics is used as an analytical tool to investigate wine authenticity issues. Aging authentication ensures that the wine has undergone the necessary maturation and developed its desired organoleptic characteristics. Considering that aged wines constitute valuable commodities, the development of advanced omics techniques that guarantee aging authenticity and prevent fraud is essential. RESULTS: Α solid phase microextraction Arrow method combined with comprehensive two-dimensional gas chromatography-mass spectrometry was developed to identify volatiles in red wines and investigate how aging affects their volatile fingerprint. The method was optimized by examining the critical parameters that affect the solid phase microextraction Arrow extraction (stirring rate, extraction time) process. Under optimized conditions, extraction took place within 45 min under stirring at 1000 rpm. In all, 24 monovarietal red wine samples belonging to the Xinomavro variety from Naoussa (Imathia regional unit of Macedonia, Greece) produced during four different vintage years (1998, 2005, 2008 and 2015) were analyzed. Overall, 237 volatile compounds were tentatively identified and were treated with chemometric tools. Four major groups, one for each vintage year were revealed using the Hierarchical Clustering Analysis. The first two Principal Components of Principal Component Analysis explained 86.1% of the total variance, showing appropriate grouping of the wine samples produced in the same crop year. A two-way orthogonal partial least square - discriminant analysis model was developed and successfully classified all the samples to the proper class according to the vintage age, establishing 17 volatile markers as the most important features responsible for the classification, with an explained total variance of 88.5%. The developed prediction model was validated and the analyzed samples were classified with 100% accuracy according to the vintage age, based on their volatile fingerprint. SIGNIFICANCE: The developed methodology in combination with chemometric techniques allows to trace back and confirm the vintage year, and is proposed as a novel authenticity tool which opens completely new and hitherto unexplored possibilities for wine authenticity testing and confirmation.


Assuntos
Compostos Orgânicos Voláteis , Vinho , Vinho/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Microextração em Fase Sólida/métodos , Quimiometria , Análise por Conglomerados , Compostos Orgânicos Voláteis/análise
13.
Anal Chim Acta ; 1304: 342536, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38637048

RESUMO

Honeys of particular botanical origins can be associated with premium market prices, a trait which also makes them susceptible to fraud. Currently available authenticity testing methods for botanical classification of honeys are either time-consuming or only target a few "known" types of markers. Simple and effective methods are therefore needed to monitor and guarantee the authenticity of honey. In this study, a 'dilute-and-shoot' approach using liquid chromatography (LC) coupled to quadrupole time-of-flight-mass spectrometry (QTOF-MS) was applied to the non-targeted fingerprinting of honeys of different floral origin (buckwheat, clover and blueberry). This work investigated for the first time the impact of different instrumental conditions such as the column type, the mobile phase composition, the chromatographic gradient, and the MS fragmentor voltage (in-source collision-induced dissociation) on the botanical classification of honeys as well as the data quality. Results indicated that the data sets obtained for the various LC-QTOF-MS conditions tested were all suitable to discriminate the three honeys of different floral origin regardless of the mathematical model applied (random forest, partial least squares-discriminant analysis, soft independent modelling by class analogy and linear discriminant analysis). The present study investigated different LC-QTOF-MS conditions in a "dilute and shoot" method for honey analysis, in order to establish a relatively fast, simple and reliable analytical method to record the chemical fingerprints of honey. This approach is suitable for marker discovery and will be used for the future development of advanced predictive models for honey botanical origin.


Assuntos
Mel , Mel/análise , Espectrometria de Massas , Análise Discriminante , Cromatografia Líquida , Espectrometria de Massa com Cromatografia Líquida
14.
Nordisk Alkohol Nark ; 41(2): 142-155, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38645971

RESUMO

Background and aim: In the present study, we focus on the relationship between state authenticity - the experience of being true to oneself in a particular moment - and microdosing - a practice that implies repeatedly ingesting very small doses of psychedelics that do not reach the threshold for perceptual alterations. We propose that microdosing could increase state authenticity through influencing people's mood and the number and satisfaction with daily activities. Methods: We used self-assessments of state authenticity collected from 18 microdosers in the Netherlands across the period of 1 month for a total of 192 observations. Results: We found that on the microdosing day and the day thereafter, state authenticity was significantly higher. Furthermore, the number of activities and the satisfaction with them were higher on the day when participants microdosed, while the following day only the number of activities was higher. Both the number or activities and the satisfaction with them were positively related to state authenticity. Conclusion: We propose that feeling and behaving authentically could have a central role in explaining the positive effects of microdosing on health and wellbeing that are reported by current research.

15.
Behav Sci (Basel) ; 14(4)2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38667098

RESUMO

Amidst the burgeoning interest in rural Intangible Cultural Heritage (ICH) tourism, this study, anchored in the Stimulus-Organism-Response (S-O-R) theoretical framework, chose Meizhou Island in Fujian Province as a case study to examine the impacts of tourists' perceptions of authenticity and their engagement levels on the destination image and loyalty towards rural ICH tourism. Utilizing Structural Equation Modeling (SEM) to analyze survey data, findings revealed that higher perceptions of a destination's preservation of original characteristics and traditional values correlate with a more favorable overall perception of the destination, albeit with smaller impact on emotional connections. Conversely, depth of tourist engagement was shown to enhance both understanding and emotional bonds with the destination. Further, familiarity with the destination was found to foster affection, thereby increasing the likelihood of repeat visits or recommendations. The more tourists know about a place, perceiving it as authentic, the more likely they are to remain loyal; similarly, deeper engagement enhances understanding and affection, increasing the probability of revisiting or recommending the place. These outcomes not only offer new insights into tourist behavior but also provide theoretical and practical guidance for the protection and development of rural ICH tourism, destination marketing, and management strategies, thus promoting the sustainable development of rural ICH tourism.

16.
Med Teach ; : 1-9, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38635469

RESUMO

INTRODUCTION: Whilst rarely researched, the authenticity with which Objective Structured Clinical Exams (OSCEs) simulate practice is arguably critical to making valid judgements about candidates' preparedness to progress in their training. We studied how and why an OSCE gave rise to different experiences of authenticity for different participants under different circumstances. METHODS: We used Realist evaluation, collecting data through interviews/focus groups from participants across four UK medical schools who participated in an OSCE which aimed to enhance authenticity. RESULTS: Several features of OSCE stations (realistic, complex, complete cases, sufficient time, autonomy, props, guidelines, limited examiner interaction etc) combined to enable students to project into their future roles, judge and integrate information, consider their actions and act naturally. When this occurred, their performances felt like an authentic representation of their clinical practice. This didn't work all the time: focusing on unavoidable differences with practice, incongruous features, anxiety and preoccupation with examiners' expectations sometimes disrupted immersion, producing inauthenticity. CONCLUSIONS: The perception of authenticity in OSCEs appears to originate from an interaction of station design with individual preferences and contextual expectations. Whilst tentatively suggesting ways to promote authenticity, more understanding is needed of candidates' interaction with simulation and scenario immersion in summative assessment.

17.
Phytomedicine ; 128: 155322, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38569291

RESUMO

BACKGROUND: Species adulteration is a concern in herbal products, especially when plant substitutes of lower economic value replace valuable botanicals. Styphnolobium japonicum is well known as a potential adulterant of Ginkgo biloba, which is one of the most demanded medicinal plants due to its wide use in pharmaceuticals, food supplements, and traditional medicine. Despite bearing some resemblance to ginkgo's flavonol composition, S. japonicum lacks many of G. biloba's desired therapeutic properties. To prevent adulteration practices, it is crucial to implement rigorous quality control measures, including fast and simple diagnostic tools that can be used on-field. PURPOSE: This study aims to develop for the first time a species-specific loop-mediated isothermal amplification (LAMP) method for the fast identification of S. japonicum in ginkgo-containing products. METHODS: A set of four specific primers (SjF3, SjB3, SjFIP, and SjBIP) and loop primers (SjLF and SjLB) were designed for a LAMP based assay using the 5.8S partial sequence and the internal transcribed spacer 2 of nuclear ribosomal DNA of S. japonicum. RESULTS: The successful amplification of the LAMP assay was inspected through visual detection, with the highest intensity recorded at the optimal conditions set at 68 °C for 40 min. The primers showed high specificity and were able to accurately discriminate S. japonicum from G. biloba and 49 other species of medicinal plants. Furthermore, the proposed LAMP assay proved to be fast, selective, and highly sensitive, as demonstrated by the absolute and relative limits of detection, which were reached at 0.5 pg for S. japonicum DNA and 0.01 % S. japonicum in G. biloba, respectively. CONCLUSIONS: This novel approach allows easy identification and discrimination of S. japonicum as a potential adulterant of G. biloba, thus being a useful tool for quality control. Compared to chromatographic or PCR-based methods, the assay proved to be fast, sensitive and did not require expensive equipment, thus offering the possibly usage in field analysis.


Assuntos
Contaminação de Medicamentos , Ginkgo biloba , Técnicas de Diagnóstico Molecular , Técnicas de Amplificação de Ácido Nucleico , Ginkgo biloba/química , Técnicas de Amplificação de Ácido Nucleico/métodos , Contaminação de Medicamentos/prevenção & controle , Primers do DNA , DNA de Plantas/genética , Plantas Medicinais/química , Sophora japonica
18.
Food Chem ; 451: 139340, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38678649

RESUMO

Essential oils (EO), secondary metabolites of plants are fragrant oily liquids with antibacterial, antiviral, anti-inflammatory, anti-allergic, and antioxidant effects. They are widely applied in food, medicine, cosmetics, and other fields. However, the quality of EOs remain uncertain owing to their high volatility and susceptibility to oxidation, influenced by factors such as the harvesting season, extraction, and separation techniques. Additionally, the huge economic value of EOs has led to a market marked by widespread and varied adulteration, making the assessment of their quality challenging. Therefore, developing simple, quick, and effective identification techniques for EOs is essential. This review comprehensively summarizes the techniques for assessing EO quality and identifying adulteration. It covers sensory evaluation, physical and chemical property evaluation, and chemical composition analysis, which are widely used and of great significance for the quality evaluation and adulteration detection of EOs.


Assuntos
Óleos Voláteis , Controle de Qualidade , Óleos Voláteis/química , Óleos Voláteis/análise , Humanos , Contaminação de Alimentos/análise , Óleos de Plantas/química , Óleos de Plantas/análise
19.
Food Chem ; 451: 139443, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38678658

RESUMO

Acetic acid is the key organic substance used to verify the authenticity of vinegar. A new method for precisely determining acetic acid δDCH3 in vinegar via gas chromatography -pyrolytic-stable isotope ratio mass spectrometry (GC-P-IRMS) was established. The δDCH3 values were obtained via calibration with a series of standards. The optimised method demonstrated a repeatability standard deviation within 3 ‰. The standard deviation of accuracy of the new method compared with that of the SNIF-NMR method was within 2.6 ‰. The synthetic acetic acid δDCH3 values was -136.7 ‰ ± 29.6 ‰, and the δDCH3 value of acetic acid in vinegar was -414.9 ‰ ± 40.5 ‰, with significant isotopic distribution characteristics. This methodology serves as a supplementary method for measuring the δDCH3 value of acetic acid in vinegar. It has advantages over other methods in terms of time, sensitivity and operability. And provides a new idea for solving the problem of analyzing substances in the presence of exchangeable groups.


Assuntos
Ácido Acético , Cromatografia Gasosa-Espectrometria de Massas , Ácido Acético/química
20.
An. psicol ; 40(1): 150-162, Ene-Abri, 2024. tab, ilus, graf
Artigo em Inglês | IBECS | ID: ibc-229037

RESUMO

Este estudio presenta distintos tipos de evidencias de validez y confiabilidad de la Escala de Autenticidad (AS) en una muestra de Brasil y Portugal. El estudioconsiste en una encuesta con 1.077 brasileños y 622 portugueses. Se testó el modelo con tres factores correlacionados (autoalienación, vivir auténtico y aceptación de la influencia externa), el modelo unidimensional y el modelo bifactorial. Se retuvo el modelo con tres factores correlacionados, con las tres subescalas alcanzando confiabilidad moderada a buena. Análisis factorial confirmatorio multigrupo sugirió invariancia escalar para cultura, género, edad, educación, ocupación y preocupación e impacto relacionados con Covid. Los ítems fueron evaluados por graded response model(GRM), sugiriendo que las tres subescalas no discriminan las personas con altos rasgos de autenticidad. GRM y estadísticas descriptivas indican que la escala de puntuación es inapropiada, particularmente para la subescala vivir auténtico, que es afectada por efecto techo. Las asociaciones con presencia de sentido mostraron evidencia adicional de validez. A pesar de las limitaciones, la AS es una medida adecuada para evaluar la autenticidad en diferentes grupos. Se discuten posibles modificaciones para el aprimoramiento de la AS.(AU)


This study introduces distinct types of validity and reliability evidence of the Authenticity Scale (AS) in a sample from Brazil and Portugal. It consists of an online survey with 1,077 Brazilian citizens and 622 Portuguese citizens. The study tested the model with three correlated factors (self-alienation, authentic living, and accepting external influence), the unidimensional model, and the bifactor model. The model with three correlated factors was retained, with the three subscales demonstrating moderate to good reliability. Multigroup confirmatory factor analysis suggested scalar invariance across culture, gender, age, education, occupation, and Covid-related concern and impact. The items were assessed by graded response model (GRM), which suggested that the three subscales are not able to distinguish respondents with high authenticity traits. GRM and descriptive statistics indicated that the rating-scale is inappropriate, particularly for authentic living subscale, which is affected by ceiling effect. Associations with presence of meaning showed additional validity evidence. Despite the limitations, the AS is an effective measure to assess authenticity across different groups. Potential modifications for the improvement of the AS are discussed.(AU)


Assuntos
Humanos , Masculino , Feminino , Autoimagem , 35111 , Qualidade de Vida/psicologia , Valor da Vida , Reprodutibilidade dos Testes , Psicologia , Psicologia Social , Inquéritos e Questionários , Brasil , Portugal , Análise Fatorial
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