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1.
Org Biomol Chem ; 20(16): 3263-3267, 2022 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-35354199

RESUMO

A deoxygenative geminal fluorosulfonimidation of 1,2-diketones was achieved for the synthesis of tetrasubstituted α-fluoroamines under mild conditions. In this study, a transition metal-free formal N-F insertion of N-fluorobenzenesulfonimide was enabled via the Kukhtin-Ramirez reaction employing a dealkylation-resistant P(III) reagent developed in our laboratory. Computational analysis was also performed to obtain a general mechanistic picture, which explained the reactivity and selectivity for this type of reaction.


Assuntos
Cetonas , Elementos de Transição , Catálise
2.
PLoS One ; 19(5): e0303144, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38718035

RESUMO

Charitable fundraising increasingly relies on online crowdfunding platforms. Project images of charitable crowdfunding use emotional appeals to promote helping behavior. Negative emotions are commonly used to motivate helping behavior because the image of a happy child may not motivate donors to donate as willingly. However, some research has found that happy images can be more beneficial. These contradictory results suggest that the emotional valence of project imagery and how fundraisers frame project images effectively remain debatable. Thus, we compared and analyzed brain activation differences in the prefrontal cortex governing human emotions depending on donation decisions using functional near-infrared spectroscopy, a neuroimaging device. We advance existing theory on charitable behavior by demonstrating that little correlation exists in donation intentions and brain activity between negative and positive project images, which is consistent with survey results on donation intentions by victim image. We also discovered quantitative brain hemodynamic signal variations between donors and nondonors, which can predict and detect donor mental brain functioning using functional connectivity, that is, the statistical dependence between the time series of electrophysiological activity and oxygenated hemodynamic levels in the prefrontal cortex. These findings are critical in developing future marketing strategies for online charitable crowdfunding platforms, especially project images.


Assuntos
Emoções , Obtenção de Fundos , Espectroscopia de Luz Próxima ao Infravermelho , Humanos , Emoções/fisiologia , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Obtenção de Fundos/métodos , Feminino , Masculino , Adulto , Instituições de Caridade , Córtex Pré-Frontal/fisiologia , Córtex Pré-Frontal/diagnóstico por imagem , Intenção , Adulto Jovem , Mapeamento Encefálico/métodos , Crowdsourcing , Encéfalo/fisiologia , Encéfalo/diagnóstico por imagem
3.
Biosensors (Basel) ; 12(1)2022 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-35049661

RESUMO

A stress group should be subdivided into eustress (low-stress) and distress (high-stress) groups to better evaluate personal cognitive abilities and mental/physical health. However, it is challenging because of the inconsistent pattern in brain activation. We aimed to ascertain the necessity of subdividing the stress groups. The stress group was screened by salivary alpha-amylase (sAA) and then, the brain's hemodynamic reactions were measured by functional near-infrared spectroscopy (fNIRS) based on the near-infrared biosensor. We compared the two stress subgroups categorized by sAA using a newly designed emotional stimulus-response paradigm with an international affective picture system (IAPS) to enhance hemodynamic signals induced by the target effect. We calculated the laterality index for stress (LIS) from the measured signals to identify the dominantly activated cortex in both the subgroups. Both the stress groups exhibited brain activity in the right frontal cortex. Specifically, the eustress group exhibited the largest brain activity, whereas the distress group exhibited recessive brain activity, regardless of positive or negative stimuli. LIS values were larger in the order of the eustress, control, and distress groups; this indicates that the stress group can be divided into eustress and distress groups. We built a foundation for subdividing stress groups into eustress and distress groups using fNIRS.


Assuntos
Emoções , Hemodinâmica , Encéfalo/fisiologia
4.
Comput Intell Neurosci ; 2022: 1034983, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36387766

RESUMO

It is very important for consumers to recognize their wrong shopping habits such as unplanned purchase behavior (UPB). The traditional methods used for measuring the UPB in qualitative and quantitative studies have some drawbacks because of human perception and memory. We proposed a UPB identification methodology applied with the brain-computer interface technique using a support vector machine (SVM) along with a functional near-infrared spectroscopy (fNIRS). Hemodynamic signals and behavioral data were collected from 33 subjects by performing Task 1 which included the Buy-One-Get-One-Free (BOGOF) and Task 2 which excluded the BOGOF condition. The acquired data were calculated with 6 time-domain features and then classified them using SVM with 10-cross validations. Thereafter, we evaluated whether the results were reliable using the area under the receiver operating characteristic curve (AUC). As a result, we achieved average accuracy greater than 94%, which is reliable because of the AUC values above 0.97. We found that the UPB brain activity was more relevant to Task 1 with the BOGOF condition than with Task 2 in the prefrontal cortex. UPBs were sufficiently derived from self-reported measurement, indicating that the subjects perceived increased impulsivity in the BOGOF condition. Therefore, this study improves the detection and understanding of UPB as a path for a computer-aided detection perspective for rating the severity of UPBs.


Assuntos
Interfaces Cérebro-Computador , Espectroscopia de Luz Próxima ao Infravermelho , Humanos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Máquina de Vetores de Suporte , Córtex Pré-Frontal , Encéfalo
5.
Sci Rep ; 12(1): 18024, 2022 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-36289356

RESUMO

As the rate of vaccination against COVID-19 is increasing, demand for overseas travel is also increasing. Despite people's preference for duty-free shopping, previous studies reported that duty-free shopping increases impulse buying behavior. There are also self-reported tools to measure their impulse buying behavior, but it has the disadvantage of relying on the human memory and perception. Therefore, we propose a Brain-Computer Interface (BCI)-based brain signal processing methodology to supplement these limitations and to reduce ambiguity and conjecture of data. To achieve this goal, we focused on the brain's prefrontal cortex (PFC) activity, which supervises human decision-making and is closely related to impulse buying behavior. The PFC activation is observed by recording signals using a functional near-infrared spectroscopy (fNIRS) while inducing impulse buying behavior in virtual computing environments. We found that impulse buying behaviors were not only higher in online duty-free shops than in online regular stores, but the fNIRS signals were also different on the two sites. We also achieved an average accuracy of 93.78% in detecting impulse buying patterns using a support vector machine. These results were identical to the people's self-reported responses. This study provides evidence as a potential biomarker for detecting impulse buying behavior with fNIRS.


Assuntos
Interfaces Cérebro-Computador , COVID-19 , Humanos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiologia , Biomarcadores
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