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1.
Analyst ; 149(19): 4899-4907, 2024 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-39101749

RESUMEN

The gas chromatography-combustion isotope ratio mass spectrometry (GC/C/IRMS) confirmation procedure for prednisone (PS) and prednisolone (PSL) is still a great challenge for the doping control laboratory due to the many structurally similar steroids present in urinary matrices. This study aims to establish an innovative online two-dimensional high performance liquid chromatography (2D-HPLC) purification method for measuring the carbon isotope ratios (CIRs) and achieving the identification of the synthetic forms of these two endogenous anabolic androgenic steroids (EAASs). Initially, the one-dimensional chromatographic column was used to separate and purify endogenous reference compounds (ERCs), and the co-elution fluids containing PS and PSL were switched to a two-dimensional chromatographic column for further purification through an online transfer system. Then the purified compounds were analyzed using GC/C/IRMS after sample pretreatments. The results showed that the minimum detection concentration of PS and PSL reached 30 ng mL-1, and no isotope fractionation occurred during the entire collection and preparation process. This method has been validated with the WADA technical document and showed good sensitivity and selectivity, demonstrating its practical applicability for urine samples in doping control laboratories.


Asunto(s)
Isótopos de Carbono , Doping en los Deportes , Prednisolona , Prednisona , Prednisolona/orina , Prednisolona/aislamiento & purificación , Prednisolona/análisis , Cromatografía Líquida de Alta Presión/métodos , Isótopos de Carbono/química , Prednisona/orina , Humanos , Doping en los Deportes/prevención & control , Cromatografía de Gases y Espectrometría de Masas/métodos , Límite de Detección , Detección de Abuso de Sustancias/métodos
2.
Psychother Res ; : 1-12, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38700414

RESUMEN

OBJECTIVE: The Clinical Outcomes in Routine Evaluation (CORE-OM) is a measure of clinical outcomes that has been widely used in mental health research. Nevertheless, the exploration of the factor structure of the CORE-OM yields diverse results. This study aims to explore the factor structure with an innovative method known as exploratory graph analysis (EGA) and supplemented with bifactor modeling. METHOD: A Chinese version of the CORE-OM was administrated to a total of 1361 clinical college students. We first examined the factor structure of the CORE-OM using EGA, and then compared the model derived by EGA with other models using CFA to find the most reasonable model. RESULTS: The result of EGA indicated a four-factor model of CORE-OM. The CFA further suggested a bifactor model with a four-factor structure combined with a general factor. The bifactor modeling suggested a significant proportion of shared variance among the variables was attributed to the general factor. The four-factor bifactor model exhibited a satisfactory fit to the data. CONCLUSION: The results confirm the robustness and parsimonious nature of a four-factor bifactor model for the Chinese version of CORE-OM. It is suitable for measuring intrapersonal psychological distress, positive emotions, interpersonal problems, and risk-related issues among the Chinese population.

3.
J Clin Psychol ; 80(6): 1271-1285, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38366938

RESUMEN

BACKGROUND: The network analysis method emphasizes the interaction between individual symptoms to identify shared or bridging symptoms between depression and anxiety to understand comorbidity. However, the network analysis and community detection approach have limitations in identifying causal relationships among symptoms. This study aims to address this gap by applying Bayesian network (BN) analysis to investigate potential causal relationships. METHOD: Data were collected from a sample of newly enrolled college students. The network structure of depression and anxiety was estimated using the Patient Health Questionnaire-9 (PHQ-9) and the Generalized Anxiety Disorder (GAD-7) Scale measures, respectively. Shared symptoms between depression and anxiety were identified through network analysis and clique percolation (CP) method. The causal relationships among symptoms were estimated using BN. RESULTS: The strongest bridge symptoms, as indicated by bridge strength, include sad mood (PHQ2), motor (PHQ8), suicide (PHQ9), restlessness (GAD5), and irritability (GAD6). These bridge symptoms formed a distinct community using the CP algorithm. Sad mood (PHQ2) played an activating role, influencing other symptoms. Meanwhile, restlessness (GAD5) played a mediating role with reciprocal influences on both anxiety and depression symptoms. Motor (PHQ8), suicide (PHQ9), and irritability (GAD6) assumed recipient positions. CONCLUSION: BN analysis presents a valuable approach for investigating the complex interplay between symptoms in the context of comorbid depression and anxiety. It identifies two activating symptoms (i.e., sadness and worry), which serve to underscore the fundamental differences between these two disorders. Additionally, psychomotor symptoms and suicidal ideations are recognized as recipient roles, being influenced by other symptoms within the network.


Asunto(s)
Trastornos de Ansiedad , Teorema de Bayes , Comorbilidad , Humanos , Femenino , Masculino , Adulto , Adulto Joven , Trastornos de Ansiedad/epidemiología , Adolescente , Depresión/epidemiología , Trastorno Depresivo/epidemiología , Estudiantes/psicología , Estudiantes/estadística & datos numéricos
4.
Behav Sci (Basel) ; 12(12)2022 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-36546959

RESUMEN

Previous studies have explored the differences in moral judgments under normal situations and acute stress using the Trier Social Stress Test (TSST). The present study examined whether anticipatory stress (i.e., induced by an anticipated speech) could elicit similar effects and further explored the mediation of emotional responses between acute stress and moral judgments with a process-dissociation approach. Fifty-three undergraduate students (20 males and 33 females) were randomly assigned to the stress and control groups. In the first stage, they were instructed to prepare a public speech (the stress group) or just recall events during the previous vacation (the control group). In the second stage, they reported emotional valence and arousal for each moral dilemma in a set of 12 moral dilemmas, followed by judgments on moral acceptability of the agent's action. The manipulation check confirmed that anticipatory stress was reliably induced, as indicated in both self-reported and physiological data. The traditional dilemma analysis revealed that participants in the stress group would make fewer utilitarian judgments than those in the control group. The process dissociation (PD) analyses further revealed that the stress group exhibited higher deontological inclinations than the control group, but no significant differences in utilitarian inclinations. Emotional valence played a mediating role in the association between stress and deontological inclinations. To sum up, our study extended the investigation of the relationship between acute stress and moral judgment to anticipatory stress, clarified its distinct impact on deontological and utilitarian inclinations, and revealed the mediating effect of emotional valence.

5.
BMC Public Health ; 22(1): 1789, 2022 09 21.
Artículo en Inglés | MEDLINE | ID: mdl-36131316

RESUMEN

BACKGROUND: As the number of older people is rapidly growing, prevention, screening, and treatment of mental health problems (including anxiety and depression) in this population increasingly become a heavy burden to individuals, families, and even the whole society. The Kessler-6 screening measure (K6) is an efficient and effective instrument for general mental health problems. However, few studies have examined its measurement invariance across time, which is particularly important in longitudinal studies, such as exploring developmental trajectories of non-specific psychological distress and evaluating the effects of certain interventions. METHODS: The current study investigated the factor structure and the longitudinal measurement invariance of the K6 among a national representative elder sample of China. Longitudinal data in two survey waves (the year 2010, and the year 2014) from the China Family Panel Studies were drawn for secondary data analysis. A total of 3845 participants aged 60 years old and above (52.2% male, mean age = 66.99 years, SD = 5.93 years) responded to both waves of the survey. RESULTS: A comparison of four existing models with confirmatory factor analysis supported a two-factor solution of the K6. A series of multi-group confirmatory factor analyses further indicated that the K6 held strict longitudinal measurement invariance across time. Additionally, the internal consistency indices across time and the stability coefficients over time were acceptable. CONCLUSIONS: The findings further confirmed the psychometric defensibility of the K6 when used in the old Chinese population. The longitudinal measurement invariance justified comparisons of psychological distress scores among different measurement time points.


Asunto(s)
Estrés Psicológico , Anciano , China/epidemiología , Análisis Factorial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Psicometría , Reproducibilidad de los Resultados , Estrés Psicológico/psicología , Encuestas y Cuestionarios
6.
BMC Geriatr ; 22(1): 144, 2022 02 19.
Artículo en Inglés | MEDLINE | ID: mdl-35183102

RESUMEN

BACKGROUND: The 15-item Geriatric Depression Scale (GDS-15) shows good performance in detecting depression among older persons, but its applicability has not been well studied in non-Western oldest-old adults and centenarians. This study aimed to evaluate the psychometric property of the GDS-15 and a simplified version among a large representative longevous population in China. METHODS: A total of 1624 individuals (786 oldest-old persons aged from 80 to 99 years; 838 centenarians aged 100+ years) participated in this study. Home interviews with structured questionnaires were conducted to collect sociodemographic data. Depressive symptoms were measured using the Chinese GDS-15 version. We implemented mixed methods for the psychometric evaluation of the GDS-15. Cronbach's α coefficient and item-total correlation coefficients were used to evaluate the internal consistency. A standard expert consultation was conducted to test the content validity of each item. Multiple factor analyses were used to explore the optimal factor structure and measurement invariance. RESULTS: The α coefficient of the GDS-15 was 0.745, while two items impaired the overall consistency reliability. Nineteen experts rated the applicability for each item and provided removal suggestion. Five items with less validity were removed, and a simplified 10-item GDS model with three-factor structure was proposed as an optimal solution. The GDS-10 model showed factorial equivalence across age, sex, residence, and education in multi-group confirmatory factor analyses. CONCLUSIONS: The original GDS-15 has acceptable internal reliability, known-group validity, and concurrent validity among Chinese community-dwelling oldest-old and centenarians; however we provided preliminary evidence indicating that individual items related to somatic function or social activities may not be applicable for this population. The modified GDS-10 can be proposed as a potentially more practical and comprehensible instrument for depression screening.


Asunto(s)
Centenarios , Depresión , Anciano , Anciano de 80 o más Años , Depresión/diagnóstico , Depresión/epidemiología , Análisis Factorial , Evaluación Geriátrica , Humanos , Psicometría , Reproducibilidad de los Resultados , Encuestas y Cuestionarios
7.
Cancer Manag Res ; 13: 6517-6525, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34447269

RESUMEN

PURPOSE: Papillary thyroid carcinoma (PTC) is the most common type of thyroid cancer. LncRNA HOTAIR (HOx Transcript AntIsense RNA) and Galectin-3 are involved in PTC. This study explored the clinical effect of lncRNA HOTAIR/Galectin-3 on PTC patients. METHODS: Subjects were assigned into PTC (160 cases) and benign thyroid tumor groups (150 cases). Fasting peripheral venous blood was collected. LncRNA HOTAIR/Galectin-3 expressions in serum were detected. Subjects were assigned into HOTAIR/Glactin-3 high/low expression groups and their correlation with age, gender, BMI, tumor size, pathological stage, TSH, TPO-Ab, and TG-Ab in PTC was analyzed. Receiver operating characteristic (ROC) curve was conducted on diagnostic efficacy of HOTAIR or/and Galectin-3. The difference of area under the curve (AUC) was compared and analyzed. RESULTS: HOTAIR and Glactin-3 were higher in PTC group and correlated with tumor pathological stage. Higher HOTAIR/Glactin-3 expression indicated a more advanced TNM stage. LncRNA HOTAIR was positively correlated with TPO-Ab and TG-Ab. AUC of HOTAIR for PTC diagnosis was 0.895, with 96.00% specificity and 80.63% sensitivity. AUC of Glactin-3 for PTC diagnosis was 0.817, with 66.67% specificity and 78.75% sensitivity. AUC of HOTAIR combining with Glactin-3 for PTC diagnosis was 0.969 with 96.00% specificity and 87.50% sensitivity. AUC of lncRNA HOTAIR was higher than that of Glactin-3, while AUC of the combination was higher than that of lncRNA HOTAIR or Glactin-3. CONCLUSION: LncRNA HOTAIR and Glactin-3 were highly expressed in PTC. The combination detection of lncRNA HOTAIR/Glactin-3 had higher diagnostic efficiency on the differential diagnosis of benign thyroid tumor and PTC.

8.
Cancer Biother Radiopharm ; 36(2): 167-173, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32608994

RESUMEN

Background: Tumor-infiltrating lymphocytes have been reported to be associated with response to neoadjuvant chemotherapy and survival in breast cancer (BC) patients. However, little is known about the value of peripheral blood parameter in predicting the prognosis in BC. Methods: In this study, parameters of complete blood count from 417 BC patients with a median 7.6-year follow-up after surgery were collected and correlated with patient survival. Results: It was found that leukocyte counts were positively correlated with disease-free survival (DFS, p = 0.016) and overall survival (OS, p = 0.014), whereas platelet counts were negatively correlated with DFS (p = 0.003) and OS (p = 0.082) in BC. Leukocyte and platelet counts were independent prognostic factors for the BC patient survival. Besides, the prognostic value of leukocyte and platelet counts was further evaluated in the BC patients with different molecular subtypes. Together, BC patients with high leukocyte counts and low platelet counts had better DFS (p = 0.001) and OS (p = 0.017) than the other patients. Conclusion: Parameters of complete blood count could be acquired easily and serve as cost-effective prognostic biomarkers in BC.


Asunto(s)
Plaquetas/metabolismo , Neoplasias de la Mama/sangre , Leucocitos/metabolismo , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Supervivencia sin Enfermedad , Femenino , Humanos , Persona de Mediana Edad , Pronóstico
9.
Front Psychiatry ; 11: 573530, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33110414

RESUMEN

BACKGROUND: The Pittsburgh Sleep Quality Index (PSQI) is a widely used self-report questionnaire that measures general sleep quality in general populations. However, its psychometric properties have yet to be thoroughly examined in longevous persons. OBJECTIVES: This study aimed to explore the reliability, validity and factor structure of the Chinese-language version of the PSQI in community-dwelling centenarians. METHODS: A total of 958 centenarians (mean age = 102.8 years; 81.8% females) recruited from 18 regions in Hainan, China, completed the PSQI scale. Cronbach's alpha coefficient was used to measure the internal consistency. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were performed to explore the validity and factor structure of the PSQI in this sample. Correlations between the global PSQI score and physical function, depression symptoms, self-reported health status and subjective well-being were used to assess divergent validity. RESULTS: The Cronbach's α coefficient of the PSQI was 0.68, and it increased to 0.78 after two components (medication use and daytime dysfunction) were removed. The Spearman correlation coefficients of the PSQI score with each component were statistically significant (P<0.01). EFA yielded a two-factor structure model of the original PSQI-7 and a one-factor structure model of the simplified PSQI-5. The one-factor model with five components (χ2/df =1.59, CFI=0.99, RMSEA=0.03) fit the data well and had good configural invariance across demographic characteristics (0.53<Δχ2<5.58, P>0.05). CONCLUSIONS: The original PSQI showed acceptable applicability in Chinese community-dwelling centenarians, and its psychometric characteristics moderately improved after sleeping medication and daytime dysfunction were removed. Further validation studies on PSQI are needed among centenarians from varied backgrounds.

10.
BMC Geriatr ; 20(1): 361, 2020 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-32962656

RESUMEN

BACKGROUND: The aging population increases rapidly across the world. Timely and effective screening of their mental-health problems is important to individuals, families, and the whole society. The Kessler-6 screening measure (K6) is a very popular instrument for non-specific psychological distress. However, few studies have focused on the psychometric properties of this instrument in the older population. METHODS: The present study employed Mokken scale analysis to evaluate its dimensionality and structure. This study also used differential item functioning (DIF) to examine whether the same structure existed across sex in a national representative sample of old Chinese people. Data were drawn from a public data set, the 2010 China Family Panel Studies (CFPS2010), and responses from a total of 6450 participants aged 60 years old and above (3136 males and 3314 females) were included in the final analysis. RESULTS: Mokken scale analysis supported the unidimensional structure of the K6. Differential item functioning (DIF) analysis revealed that two of the six items ("Hopeless" and "Everything was an effort") were marked for DIF based on the Chi-square. However, their impacts were negligible in terms of McFadden's pseudo R2. CONCLUSIONS: The K6 demonstrates adequate psychometric properties in the old Chinese population. The sum of all six items can be used as an indicator of non-specific psychological distress. Differences in the indicator across sex should be considered as a real difference in psychological distress between the female and the male.


Asunto(s)
Pueblo Asiatico , Escalas de Valoración Psiquiátrica/normas , Estrés Psicológico/diagnóstico , Encuestas y Cuestionarios/normas , Factores de Edad , Anciano , Anciano de 80 o más Años , Envejecimiento/psicología , China/epidemiología , Femenino , Humanos , Masculino , Psicometría , Reproducibilidad de los Resultados , Estrés Psicológico/etnología , Estrés Psicológico/psicología
11.
Anal Chem ; 92(14): 9528-9535, 2020 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-32598141

RESUMEN

A novel magnet array system was constructed to use Larmor precession for boosting the signal intensity of rf-GD-MS. The enhancement mechanism with four magnet array devices of a single-block magnet and 2 × 2, 3 × 2, and 3 × 4 magnet arrays was simulated and studied by COMSOL Multiphysics Software 5.4.0 (COMSOL) to determine if the electrons in the discharge plasma could perform Larmor precession along the direction perpendicular to the magnetic field. Induced by Larmor precession, inelastic collisions between the primary electrons and the sample produced numerous secondary electrons and further improved the ionization efficiency. Moreover, the fuzzy synthetic evaluation result predicted that the device with a 3× 2 magnet array would display the greatest enhancement effect among the four devices. On the basis of these theoretical studies, a magnet array system with four magnet array devices was fabricated and utilized for studies of two scintillation crystals BGO and PWO. The observations indicated that the signal intensities obtained for 209Bi and 208Pb with the magnet array system were 630-3600 times of that obtained without a magnet and were enhanced by a factor of 1.5-2.8 compared with a previously reported stacked magnetic device. Two NIST samples were used to validate the method, and the results suggested that relative errors were less than 10%, and the lowest detection limit for the 3 × 2 magnet array could reach 0.0032 µg·g-1. Furthermore, the magnet array enhancement system with Larmor precession offers an efficient and sensitive approach for direct analysis of nonconducting materials.

12.
BMC Geriatr ; 19(1): 313, 2019 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-31729965

RESUMEN

BACKGROUND: Anxiety symptoms are pervasive among elderly populations around the world. The Geriatric Anxiety Inventory (the GAI) has been developed and widely used in screening those suffering from severe symptoms. Although debates about its dimensionality have been mostly resolved by Molde et al. (2019) with bifactor modeling, evidence regarding its measurement invariance across sex and somatic diseases is still missing. METHODS: This study attempted to provide complemental evidence to the dimensionality debates of the GAI with Mokken scale analysis and to examine its measurement invariance across sex and somatic diseases by conducting differential item functioning (DIF) analysis among a sample of older Chinese adults. The data was from responses of a large representative sample (N = 1314) in the Chinese National Survey Data Archive, focusing on the mental health of elderly adults. RESULTS: The results of Mokken scale analysis confirmed the unidimensionality of the GAI, and DIF analysis indicated measurement invariance of this inventory across individuals with different sex and somatic diseases, with just a few items exhibiting item bias but all of them negligible. CONCLUSIONS: All these findings supported the use of this inventory among Chinese elders to screen anxiety symptoms and to make comparisons across sex and somatic diseases.


Asunto(s)
Ansiedad/epidemiología , Ansiedad/psicología , Pueblo Asiatico/psicología , Escalas de Valoración Psiquiátrica/normas , Encuestas y Cuestionarios/normas , Anciano , Anciano de 80 o más Años , Ansiedad/diagnóstico , China/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Psicometría , Distribución Aleatoria , Reproducibilidad de los Resultados
13.
Rev Sci Instrum ; 90(8): 084705, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31472637

RESUMEN

A low-frequency superconducting cavity is needed in main accelerators for storage ring light sources with ultralow emittance. A compact 166.6 MHz superconducting proof-of-principle cavity was designed adopting a quarter-wave ß = 1 geometry for a High Energy Photon Source (HEPS). It is a 6 GeV diffraction-limited synchrotron light source currently being developed at the Institute of High Energy Physics. The cavity is exceedingly compact in size yet possessing a low resonant frequency. The nearest higher order mode is largely separated from the fundamental, making the cavity an attractive geometry for effective damping of these modes in high current accelerators such as HEPS. The achieved accelerating voltage of 3.0 MV is well beyond the designed 1.5 MV and required 1.2 MV for HEPS operation. High surface electromagnetic fields were reached with excellent rf and mechanical performances, and multipacting barriers were easily processed. This constitutes the first demonstration of a compact low-frequency ß = 1 superconducting cavity for HEPS. The design, fabrication, surface preparation, and cryogenic tests of the cavity are presented.

14.
Anal Chim Acta ; 1048: 115-122, 2019 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-30598140

RESUMEN

It is difficult to conduct rapid quantitative studies by direct analysis of mass spectrometry because of the matrix effects. In order to overcome the matrix effects in rapid quantitative analysis of complex sample and to find a rapid mass spectrometry method for capsaicin quantitation, the thermal desorption carbon fiber ionization mass spectrometry (TD-CFI-MS) was developed and optimized. TD-CFI-MS allows timesaving, less cost, less solvent consumption and no auxiliary gas. In this method the metal ceramics heater (MCH) was used for analyte desorption. The protonated water clusters in carbon fiber ion source provided proton for analytes through ion-molecular interactions. Desorption and ionization processes were separated in time and space so the analyte was less affected by the matrix during ionization, and the signal intensity of the analyte was enhanced. The matrix effects were investigated by the quantitative analysis of capsaicin in various samples using TD-CFI-MS, and the results were within 93.3-97.6% which indicated that almost no significant effects on the quantitation of capsaicin by this method. Finally, TD-CFI-MS was successfully applied for the quantitation of capsaicin in various real samples including foods and medicines indicating that this technique was a valuable strategy.


Asunto(s)
Capsaicina/análisis , Espectrometría de Masas/métodos , Análisis de los Alimentos/métodos , Calefacción , Límite de Detección , Preparaciones Farmacéuticas/análisis
15.
Front Psychol ; 9: 1702, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30254597

RESUMEN

Stress is prevalent in our daily life, and people often make moral decision-making in a stressful state. Several studies indicated the influence of acute stress on moral decision-making and behavior. The present study extended the investigation to chronic stress, and employed a new approach, the CNI model, to add new insights regarding the mechanism underlying the association between chronic stress and moral decision-making. A total of 197 undergraduates completed the Perceived Stress Scale and made moral decision-making on a series of deliberately designed moral dilemmas. The results indicated that higher chronic stress was related to more deontological moral choices. The process-dissociation analyses revealed that chronic stress was marginally significantly associated with deontological inclinations but not with utilitarian inclinations. And the CNI model analyses suggested that the high-stress group (above the median) showed a stronger general preference for inaction than the low-stress group (below the median) did, but there were no significant differences in sensitivity to consequences or sensitivity to moral norms between the two groups. Finally, the implications of the findings were discussed.

16.
J Am Soc Mass Spectrom ; 29(6): 1319-1322, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29679286

RESUMEN

Fast eruption desorption ionization (FEDI) technique was developed for simple, rapid, and sensitive analysis of various compounds. The FEDI allows three analytical modes each with the unique characteristic. The results demonstrated that non-assisted eruption was suitable for stable and volatile compounds, energetic material (EM)-assisted for nonvolatile molecules especially metal compounds, and solvent-assisted eruption for fragile molecules. High-quality mass spectra with intact ions of analytes were obtained in positive and negative ion modes. Graphical Abstract ᅟ.

17.
Talanta ; 182: 241-246, 2018 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-29501147

RESUMEN

Ambient flame ionization (AFI) coupled with triple quadrupole tandem mass spectrometry was developed for quantitative analysis of sodium saccharin (SAC) in various food samples. Typically, the micro-flame by the combustion of n-butane provided a heating zone for fast desorption and ionization of analytes in milliseconds. Then high ion abundance of analyte could be produced in a short time, which made AFI-MS possess a very high sensitivity for SAC detection and was particularly appropriate for the quantification in multiple reaction monitor (MRM) mode. Liquid samples were introduced into outer flame using dip-it tips in order to facilitate a rapid and high-throughput analysis. Saccharin-d4 was used as the internal standard to compensate for the variations of the ion intensities. With a minimal sample preparation, a linear range of 4-100 µg/mL was developed with all linear relationships of different matrices (including coke, juice, liquors, sunflower seeds and sweetmeats) greater than 0.992. Recoveries for coke and apple matrices were ranged from 88.4% to 108.9% at the concentration of 5, 20, 80 µg/mL and the limits of detection (LODs) were in the range of 0.12-0.21 µg/mL. Furthermore, the feasibility of this method was exhibited by the quantification analysis of SAC in seventeen real samples. These results indicated that AFI-MS was a valuable strategy for rapid screening detection and precise quantification analysis of SAC in food.


Asunto(s)
Ionización de Llama/métodos , Ensayos Analíticos de Alto Rendimiento , Sacarina/análisis , Espectrometría de Masa por Ionización de Electrospray/métodos , Edulcorantes/análisis , Bebidas Alcohólicas/análisis , Calibración , Ionización de Llama/instrumentación , Jugos de Frutas y Vegetales/análisis , Humanos , Límite de Detección , Productos de la Carne/análisis , Estándares de Referencia , Semillas/química , Espectrometría de Masa por Ionización de Electrospray/instrumentación
18.
Front Psychol ; 8: 2095, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29234299

RESUMEN

Previous studies have demonstrated the key role of emotion in moral judgment, and explored the relationship between emotion regulation and moral judgment. The present study investigated the influence of individual differences in emotion regulation difficulties on moral judgment. Study 1 examined whether individuals with high emotion regulation difficulties made a more deontological judgment. Study 2 explored the underlying mechanism using a process-dissociation approach, examining whether deontological inclinations and utilitarian inclinations separately or jointly accounted for the association. The results indicated that individuals with high emotion regulation difficulties rated the utilitarian actions less morally appropriate, and one's deontological inclinations mediated the association between emotion regulation difficulties and moral judgment.

19.
Front Psychol ; 8: 1805, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29075229

RESUMEN

Emotion plays an important role in moral judgment, and people always use emotion regulation strategies to modulate emotion, consciously or unconsciously. Previous studies had investigated only the relationship between emotion regulation strategies and moral judgment in the Harm domain, and revealed divergent results. Based on Moral Foundations Theory, the present study extended the investigation into moral judgment in all five moral domains and used a set of standardized moral vignettes. Two hundred and six college students filled in the Emotion Regulation Questionnaire and completed emotional ratings and moral judgment on moral vignettes from Moral Foundations Vignettes. Correlation analysis indicated that habitual cognitive reappraisal was negatively related to immorality rating in Harm, Fairness, and Loyalty domains. Regression analysis revealed that after controlling the effect of other variables, cognitive reappraisal negatively predicted immorality ratings in the Harm and Fairness domains. Further mediation analysis showed that emotional valence only partially explained the association between cognitive reappraisal and moral judgment in Harm area. Some other factors beyond emotional valence were suggested for future studies.

20.
Sci Rep ; 7(1): 153, 2017 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-28273956

RESUMEN

In one of the largest oil-gas fields in Daqing, China, the anticlines are important structures that hold natural gas. The origin of the symmetric anticlines, which have bends on both the limbs, remains under debate. This is especially true in the case of the anticline in Xujiaweizi (XJWZ), which has recently been the focus of gas exploration. A compressive force introduced by a ramp/flat fault was suggested as its origin of formation; however, this is inconsistent with the reconstruction of the regional stress fields, which show an extensive environment. An alternative explanation suggests a normal fault-related fold under extensive stress. However, this mechanism has difficulty explaining the very localized, rather than wide-spread, development of the anticline along the proposed controlling normal fault. The well-developed bends on both limbs of the anticline are also very different from the typical roll-over anticline. Here, we conduct an experimental study showing that the very localized development of the bent-on-both-limbs anticline is controlled by the geometry of the underlying fault-plane. A ramp/flat fault plane can introduce an anticline with bends on both limbs, while a smooth fault plane will develop a roll-over anticline with a bend on only one limb.

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