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1.
Talanta ; 281: 126933, 2025 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-39326112

RESUMO

Ferrous ion (Fe2+) can indicate the redox situation of water and also plays an important role in maintaining the ecological balance of water bodies. However, due to the redox-active property of Fe2+, it is still a huge challenge to sensitively and accurately determine Fe2+ especially in interstitial water. Herein, we prepared a ferrozine gel rod for valence fixation during sampling and subsequent smartphone-based detection of Fe2+. The electrode potential of the redox pair can be varied through the formation of Fe2+-ligand complexes, and when Ecomplex was higher than [Formula: see text] , the oxidation of Fe2+ by O2 was hindered, thus achieving the valence fixation of Fe2+. Six ligands were screened, and it was found that ferrozine could effectively increase the redox potential after complexing with Fe2+, and also exhibits an obvious color change while fixing the valence of Fe2+. To facilitate Fe2+ detection, a cross-linked porous polymer gel rod prepared by acrylamide and sodium alginate was used to encapsulate the ferrozine molecules. The ferrozine gel rod enabled fixation the valence of Fe2+ longer than 30 days, and the resulted purple-red color was pictured and analyzed by a smartphone. Ultimately, the developed ferrozine gel rod sensing system was able to achieve sensitive and linear detection of Fe2+ in the range of 1-200 µM with the limit of detection as low as 0.33 µM, and it also exhibited excellent selectivity and anti-interference ability. The accuracy and reliability of the method was verified by the determination of Fe2+ in spiked water samples and certified standard reference water samples. Finally, the ferrozine gel rod sensing system was successfully applied to in-situ detection of Fe2+ in interstitial water, overlying water and upper water of lake and river. This facile system that enabled valence fixation and fast detection is promising for detection of Fe2+ in environmental waters.

2.
J Colloid Interface Sci ; 678(Pt B): 545-558, 2025 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-39260302

RESUMO

Controlling high recombination of photogenerated carriers and optimizing low cycling of metal valence states are the two key control steps in enhancing photo-Fenton oxidation. To achieve multiscale synergy of photo-Fenton degradation, graphite carbon-modified copper ferrite composites (C/CFO) with poor/rich dual electron reaction centers were synthesized through direct carbonization of Fe/Cu bimetallic organic frameworks. A novel photo-Fenton catalytic system was constructed by irradiating the Fenton reaction with visible light. The photo-Fenton degradation efficiency of C/CFO for tetracycline (100 mg‧L-1) was 93.69% ± 0.02%, and the degradation rate constant was 4.84 times higher than that of the control. Optimized preparation and catalytic conditions, ensured good cyclic stability and broad applicability of C/CFO. This excellent stability performance improvement can be attributed to the following main factors: (1) The introduction of graphite carbon not only increases the specific surface area of C/CFO, but also acts as a bridge between the dual electron reaction centers, facilitating the transfer of photogenerated electrons. (2) On the one hand, the electron-poor reaction centers Fe and Cu capture photogenerated electrons, accelerate the Fenton reaction, and realize the valence cycling of Fe and Cu. On the other hand, the electron-rich reaction centers (oxygen vacancies) act as active sites for H2O2 adsorption, which greatly accelerate the decomposition of H2O2. Overall, the synergy of dual electron reaction centers effectively promoted photo-Fenton oxidation.

3.
Schizophr Res Cogn ; 39: 100334, 2025 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-39498297

RESUMO

Auditory hallucinations (AH) are the most common symptom of psychosis. The voices people hear make comments that are benign or even encouraging, but most often voices are threatening and derogatory. Negative AH are often highly distressing and contribute to suicide risk and violent behavior. Biological mechanisms underlying the valence of voices (i.e., positive, negative, neutral) are not well delineated. In the current study, we examined whether AH voice valence was associated with increased activation of the Defensive Motivational System, as indexed by central and autonomic system response to unpleasant stimuli. Data were evaluated from two studies that used a common symptom rating instrument, the Psychotic Symptom Rating Scale (PSY-RATS), to measure AH valence. Participants included outpatients diagnosed with SZ. Tasks included: Study 1: Trier Social Stress Task while heart rate was recorded via electrocardiography (N = 27); Study 2: Passive Viewing Task while participants were exposed to pleasant, unpleasant, and neutral images from the International Affective Picture System (IAPS) library while eye movements, pupil dilation, and electroencephalography were recorded (N = 25). Results indicated that negative voice content was significantly associated with: 1) increased heart rate during an acute social stressor, 2) increased pupil dilation to unpleasant images, 3) higher neural reactivity to unpleasant images, and 4) a greater likelihood of having bottom-up attention drawn to unpleasant stimuli. Findings suggest that negative AH are associated with greater Defensive Motivational System activation in terms of central and autonomic nervous system response.

4.
Acta Psychol (Amst) ; 251: 104573, 2024 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-39488879

RESUMO

Skin conductance response (SCR) serves as a dependable marker of sympathetic activation used to measure emotional arousal. This study investigates the impact of presentation modality (face or word) on the degree of emotional discrimination elicited by SCR. Facial expressions or words associated with six basic emotions-anger, happiness, disgust, fear, sadness, and surprise-were studied among 102 participants. The amplitude of SCR was accurately predicted by subjective arousal ratings of these stimuli, but not by valence ratings. The habituation process to emotional and neutral stimuli across six successive presentations was characterized by an exponential decay function, capturing the rate at which SCR response diminishes in relation to the preceding trial of the same stimulus. Through the subtraction of the response to neutral stimuli from the emotion-evoked SCR, it was demonstrated that the initial presentation of each emotion elicits a substantial response, particularly attributable to the emotional content. Notably, the initial emotional response to faces expressing happiness, disgust, and sadness surpassed that of words conveying the same emotions. The results indicate that different emotional responses can be quantified using a simple electrical instrument.

5.
Q J Exp Psychol (Hove) ; : 17470218241296695, 2024 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-39439183

RESUMO

Affective words can be classified into two types: emotion words (EM words, e.g., "happy") and emotion-laden words (EL words, e.g., "wedding"). Several studies have shown differences in processing between EM and EL words, although results are inconclusive. These two types of words may have representational differences because affective content is an inherent part of the semantic features of EM words (i.e., denotative meaning) but not of EL words, whose affective content is part of their connotative meaning (i.e., these words do not name emotions, but are associated to emotions). In this study, we tested a set of Chinese EM and EL words. Both conditions included positive and negative words. The study involved two tasks, an implicit task, in which emotional content was not relevant (lexical decision task, LDT), and an explicit task, in which the emotional content was relevant (affective categorization task, ACT). Our results showed that participants responded faster to EM words than to EL words. This advantage was mostly observed in the ACT and with negative words. These results reveal differences in processing between EM and EL words which can be related to the greater relevance of affective content in the meaning of EM words compared to EL words.

6.
Acta Psychol (Amst) ; 250: 104541, 2024 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-39447426

RESUMO

BACKGROUND: Virtual Reality (VR) has demonstrated tremendous potential to transform the tourism industry, offering tourists immersive experiences in remote destinations with reduced costs. Drawing on the technology acceptance model (TAM) and expectancy theory, we investigated the intricate interplay between expectancy, valence, and instrumentality and tourists' VR tourism intention through perceived ease of use and perceived usefulness. METHODS: Our structural equation modeling results based on the survey of 282 VR tourists in China revealed that expectancy, valence, and instrumentality significantly impact perceived ease of use, which in turn affects VR tourism intention. RESULTS: Perceived ease of use and perceived usefulness each mediate the relationship between expectancy, valence, instrumentality, and VR tourism intention. CONCLUSION: These results contribute to the VR tourism literature and offer practical insights for destination operators and marketers aiming to enhance VR tourism experiences and promote technology adoption in the tourism industry.

7.
Front Psychol ; 15: 1401084, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39439759

RESUMO

This exploratory study examined the potential of word embeddings, an automated numerical representation of written text, as a novel method for emotion decomposition analysis. Drawing from a substantial dataset scraped from a Social Media site, we constructed emotion vectors to extract the dimensions of emotions, as annotated by the readers of the texts, directly from human language. Our findings demonstrated that word embeddings yield emotional components akin to those found in previous literature, offering an alternative perspective not bounded by theoretical presuppositions, as well as showing that the dimensional structure of emotions is reflected in the semantic structure of their text-based expressions. Our study highlights word embeddings as a promising tool for uncovering the nuances of human emotions and comments on the potential of this approach for other psychological domains, providing a basis for future studies. The exploratory nature of this research paves the way for further development and refinement of this method, promising to enrich our understanding of emotional constructs and psychological phenomena in a more ecologically valid and data-driven manner.

8.
Adv Sci (Weinh) ; : e2408287, 2024 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-39413028

RESUMO

Non-volatile photomemory based on photomodulated luminescent materials offers unique advantages over voltage-driven memory, including low residual crosstalk and high storage speed. However, conventional materials have thus far been volatile and insecure for data storage because of low trap depth and single-level storage channels. Therefore, the development of a novel non-volatile multilevel storage medium for data encryption remains a challenge. Herein, a robust, non-volatile, multilevel optical storage medium is reported, based on a photomodulated Ba3MgSi2O8:Eu3+, which combined the merits of light-induced valence (Eu3+ → Eu2+) and photochromic phenomena using optical stimulation effects, accompanied by larger luminescent and color contrasts (>90%). These two unique features provided dual-level storage channels in a single host, significantly improving the data storage security. Notably, dual-level optical signals could be written and erased simultaneously by alternating 265 and 365 nm light stimuli. Theoretical calculations indicated that robust color centers induced by intrinsic interstitial Mg and vacancy defects with suitable trap depths enable excellent reversibility and long-term storage capability. By relying on different luminescent readout mechanisms, the encrypted dual-level information can be accurately decrypted by separately probing the Eu2+ and Eu3+ signals, thus ensuring information security. This study proposes a novel approach for constructing multilevel information storage channels for information security.

9.
Br J Dev Psychol ; 2024 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-39425569

RESUMO

Given that children do not always trust gossip, do they spontaneously check what they are told? We provided 5- (N = 32) and 6-year olds (N = 32) with gossip concerning characters in a cartoon they were watching, and examined whether they verified the gossip by actively re-watching the relevant episodes. Six-year olds were more likely to verify gossip than 5-year olds. When gossip targeted their favourite characters, children were more likely to verify negative when compared with positive gossip. However, when gossip targeted children's disliked characters, they showed no such valence bias. These results indicate that children's verification of gossip increases with age, and they evaluate claims selectively.

10.
Cogn Emot ; : 1-15, 2024 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-39370670

RESUMO

Emojis are frequently used in digital communication to supplement the lack of non-verbal cues, but their integration during reading has not been thoroughly examined. This study explores the interplay between language and emotion by testing the influence of emotional valence and face-status of emojis on visual word recognition. Two online experiments were conducted with 92 native English-speaking university students, examining priming effects between congruent (e.g. [Formula: see text] delicious) and incongruent (e.g. [Formula: see text] hate) prime-target pairs, varying the face-status of the emoji prime (face vs. non-face) and the valence (positive vs. negative) of the word target. Irrespective of valence, face emojis demonstrated a processing advantage over non-face emojis, implying automatic attention capture. Additionally, the results revealed an interaction between prime-target congruency and valence, with a facilitatory effect for positive, but not negative, items, suggesting a valence-specific mechanism of affective priming in the lexical decision task. The research suggests that the rapid integration of emoji content occurs during the early stages of visual word recognition, with heightened attentional sensitivity to both face-like and positive stimuli when reading digital communications.

11.
Affect Sci ; 5(3): 190-195, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39391341

RESUMO

Affective science has taken up the challenge of building a bridge between basic affective science and practical applications. The articles in the Future of Affective Science issue lay out methodological and conceptual frameworks that allow us to expand affective science into real-world settings and to handle naturalistic methods. Along with these advances, accomplishing this goal will require additionally refocusing the types of experiences we study, and the measures of experience we are interested in. This paper explores the necessity for basic affective science to embrace the messy and complex nature of human emotion in order to bridge the gap between theoretical concepts and real-world applicability. Specifically, this involves studying experiences that do not fit as neatly into dominant conceptual frameworks, such as valenced scales and the most common discrete emotion categories, and that may be more difficult to measure or experimentally control. This makes the gap between affective science and real-world feelings larger. To move the field towards incorporating emotional complexity in an empirical manner, I propose measurement standards that err on the side of less fixed-choice options and using stimuli chosen for their potential to elicit highly complex responses over time within the same individual. Designing studies that can measure these experiences will push emotion theories to explain data they were not originally designed for, likely leading to refinement and collaboration. These approaches will help capture the full spectrum of human emotional experience, leading to a more nuanced and applicable understanding of affective science.

12.
Small ; : e2403992, 2024 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-39396371

RESUMO

The transition metal with high valence state in oxyhydroxides can accelerate the reaction kinetics, enabling highly intrinsic OER activity. However, the formation of high-valence transition-metal ions is thermodynamically unfavorable in most cases. Here, a novel strategy is proposed to realize the purpose and reveal the mechanism by constructing amorphous phase and incorporating of elements with the characteristic of Lewis acid or variable charge state. A model catalyst, CeO2-NiFeOxHy, is presented to achieve the modulation of valence state of active site (Ni2+→Ni3+→Ni4+) for improved OER, leading to dominant active sites with high valence state. The CeO2-NiFeOxHy electrode exhibits superior OER performance with overpotential of 214 and 659 mV at 10 and 500 mA cm-2, respectively (without IR correction), and high stability, which are much better than those of NiOxHy, NiFeOxHy and CeO2-NiOxHy. These findings provide an effective strategy to achieve the active metals with high-valence state for highly efficient OER.

13.
Biol Psychiatry ; 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39395471

RESUMO

Accumulating evidence supports a role for altered circuit function in impaired valence processing and altered affective states as a core feature of psychiatric illnesses. We review the circuit mechanisms underlying normal valence processing and highlight evidence supporting altered function of the basolateral amygdala (BLA), valence processing and affective states across psychiatric illnesses. The mechanisms controlling network activity which governs valence processing will be reviewed in the context of potential pathophysiological mechanisms mediating circuit dysfunction and impaired valence processing in psychiatric illnesses. Finally, we review emerging data demonstrating experience-dependent, biased information routing through the BLA promoting negative valence processing and discuss the potential relevance to impaired affective states and psychiatric illnesses.

14.
Cogn Emot ; : 1-15, 2024 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-39462760

RESUMO

ABSTRACTImage data serves as a valuable resource for investigating relationships between colors and emotions. This study conducts an image-based visual corpus analysis on the color associations of 100 Chinese emotion words, aiming to uncover the pivotal roles of colors in understanding emotional concepts. The study addresses two primary objectives: (i) examining the interrelations among four affective properties (valence, arousal, prototypicality, and emotionality) and four image-based color attributes (Jz: a dimension depicting black-white color distinction, Az: a dimension for green-red, Bz: a dimension for blue-yellow, and color variability) associated with these emotion words; and (ii) assessing the efficacy of image-based color information in profiling affective (dis)similarities among different emotion words. The empirical results reveal (i) significant positive correlations between color variability and arousal, Jz and valence, Az and arousal, Bz and valence, as well as a negative correlation between Jz and prototypicality; (ii) the effectiveness of image-based color information in depicting the valence-dominated affective (dis)similarities among the 100 Chinese emotion words. This study contributes image-based empirical support to complement existing research on color-emotion mappings. Moreover, it advances methodological approaches by advocating for the utilisation of image data to address theoretical inquiries in cognitive science.

15.
Front Behav Neurosci ; 18: 1415047, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39450346

RESUMO

Safety learning allows the identification of non-threatening situations, a learning process instrumental for survival and psychic health. In contrast to fear learning, in which a sensory cue (conditioned stimulus, CS) is temporally linked to a mildly aversive stimulus (US), safety learning is studied by presenting the CS and US in an explicitly unpaired fashion. This leads to conditioned inhibition of fear responses, in which sensory cues can acquire a safety meaning (CS-). In one variant of safety learning, an auditory CS- was shown to reduce contextual fear responses during recall, as measured by freezing of mice. Here, we performed control experiments to test whether auditory stimuli might interfere with freezing by mechanisms other than safety learning, a phenomenon also called external inhibition. Surprisingly, when auditory stimulation was omitted during training (US-only controls), such stimuli still significantly suppressed contextual freezing during recall, indistinguishable from the reduction of freezing after regular safety training. The degree of this external inhibition was positively correlated with the levels of contextual freezing preceding the auditory stimulation. Correspondingly, in fear learning protocols which employ a new context during recall and therefore induce lower contextual freezing, auditory stimuli did not induce significant external inhibition. These experiments show that in safety learning protocols that employ contextual freezing, the freezing reduction caused by auditory stimuli during recall is dominated by external inhibition, rather than by learned safety. Thus, in safety learning experiments extensive controls should be performed to rule out possible intrinsic effects of sensory cues on freezing behavior.

16.
J Phys Condens Matter ; 37(2)2024 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-39366422

RESUMO

Temperature dependent magnetic, electrical transport and thermal properties of polycrystalline orthorhombic CeFe2Al8intermetallic compound have been studied along with its isostructural La counterpart, LaFe2Al8. For the cerium compound, low fielddcmagnetization exhibits an antiferromagnetic like ordering (TN) ∼ 4 K. The main feature of the magnetic susceptibility plot is a broad hump spanning a large temperature range, indicating mixed valence of Ce in the compound, in good agreement with reported literature. However, contrary to the reported observations we find that the mixed valence state is very robust and was evident even up to very high magnetic fields (> 2 T). Further, in this work we report 3d core level photoemission spectra of cerium in CeFe2Al8, to understand the valence state of cerium ions in this system. Additionally, from resistivity measurements it is found that, CeFe2Al8is metallic with no indication of any anomaly, till the lowest temperature of measurement. Specific heat measurements show very low value of heat capacity and electronic contribution. The isostructural La analogue, LaFe2Al8compound shows broadness in susceptibility with maxima around 44 K which may be attributed to ordering of Fe moments. The comparison of Ce and La compounds brings out the role of Fe magnetic moments which may be responsible for competing with cerium moments and resulting in the dilution of long-range magnetic order, also contributing to magnetic frustration in CeFe2Al8.

17.
ACS Appl Mater Interfaces ; 16(42): 57325-57333, 2024 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-39397708

RESUMO

Single-phase BaM4Si5O17 (M = Yb, Er, Y, Ho) ceramics have been investigated for their crystal structures, microwave dielectric properties, flexural strength, and potential applications in dielectric antennas. Rietveld refinement and TEM analysis revealed that the BaM4Si5O17 ceramics exhibit a monoclinic structure (space groups: P21/m). The εr of the BaM4Si5O17 ceramics was dominated by ionic polarizability and ρrel. The Q × f values were considerably larger at BaM4Si5O17 (M = Yb and Y) ceramics with the high Utotal and low intrinsic dielectric loss. The τf values were controlled by the MO6 octahedron distortion and -VBa. The flexural strength was mainly dominated by pores and average grain size and reached the maximum value (156 MPa) at BaY4Si5O17 ceramic with small average gain sizes and high relative density. Additionally, a patch antenna was fabricated using high-performance BaY4Si5O17 ceramic characterized by a εr value of 9.02, a Q × f value of 60620 at 12.30 GHz, and a τf value of -37.65 ppm/°C. This design achieved a high simulated radiation efficiency of 82.70% and a gain of 5.60 dBi at 6.97 GHz. indicating potential applications of BaY4Si5O17 ceramic because of its low dielectric loss and high flexural strength.

18.
Small ; : e2407554, 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39388507

RESUMO

The Cu+ active sites have gained great attention in electrochemical nitrate reduction, offering a highly promising method for nitrate removal from water bodies. However, challenges arise from the instability of the Cu+ state and microscopic structure over prolonged operation, limiting the selectivity and durability of Cu+-based electrodes. Herein, a self-reconstructed Cu2O/TiO2 nanofibers (Cu2O/TiO2 NFs) catalyst, demonstrating exceptional stability over 50 cycles (12 h per cycle), a high NO3 --N removal rate of 90.2%, and N2 selectivity of 98.7% is reported. The in situ electrochemical reduction contributes to the self-reconstruction of Cu2O/TiO2 nanofibers with stabilized Cu+ sites via the electronic metal-support interaction between TiO2 substrates, as evidenced by in situ characterizations and theoretical simulations. Additionally, density functional theory (DFT) calculations also indicate that the well-retained Cu+ sites enhance catalytic capability by inhibiting the hydrogen evolution reaction and optimizing the binding energy of *NO on the Cu2O/TiO2 NFs heterostructure surface. This work proposes an effective strategy for preserving low-valence-state Cu-based catalysts with high intrinsic activity for nitrate reduction reaction (NO3RR), thereby advancing the prospects for sustainable nitrate remediation technologies.

19.
Artigo em Inglês | MEDLINE | ID: mdl-39467301

RESUMO

AIMS: Eating disorders represent an aspect of mental illness involving failure to control eating behaviors. Food valence plays a regulatory role in eating behaviors and changes with eating experiences. Failure to control food valence may be associated with eating disorders. This study presents a newly developed behavior task-food reservation task, which assesses changes in food valence. METHODS: Over three consecutive days, mice were fed a regular diet for 30 min and subsequently were offered either palatable or low-palatable foods for 30 min. RESULTS: Mice decreased regular diet consumption on the days that it was followed by a palatable food-sweet chocolate (SC) or cheese (CH) and increased it when it was followed by a low-palatable food-bitter (dark) chocolate (BC). Our findings indicate that mice can change regular diet consumption by learning whether it will be followed by a palatable or low-palatable food. This suggests that palatable food devaluated the food valence of regular diet, whereas low-palatable food evaluated it. CONCLUSION: We developed a new food reservation task, which allows to assess experience-dependent change in the food valence of a regular diet. This task will contribute to a better understanding of the neural mechanisms underlying those changes.

20.
Sci Rep ; 14(1): 25944, 2024 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-39472724

RESUMO

Emotional contagion can be defined as the transfer of an emotional state from the demonstrator of that state towards an observer. Social buffering is a process by which the demonstrator has a reduced stress response due to the presence of one or more other individuals. While both processes are well studied separately, it is unknown whether and how both processes are related. Therefore, the aim of this study was to investigate the relation between emotional contagion and social buffering in pigs. Hereto correlations were performed between measures of emotional contagion (i.e., the difference in behaviour of observer pigs between a situation with and without demonstrator pigs present) and measures of social buffering (i.e., the difference in behaviour of demonstrator pigs in a negative situation with and without observer pigs present). The results did not point towards a clear and consistent relation as only few and contrasting correlations between measures of emotional contagion and social buffering were found, and after correcting for chance no significant correlations remained. To conclude, more research is needed on the relation between emotional contagion and social buffering to shed light on how and when emotions will spread through and/or are buffered in a group of animals.


Assuntos
Comportamento Animal , Emoções , Comportamento Social , Animais , Emoções/fisiologia , Suínos , Comportamento Animal/fisiologia , Masculino , Feminino , Estresse Psicológico/psicologia
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