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Pancreatic cancer is characterized by desmoplasia; crosstalk between pancreatic cancer cells (PCCs) and pancreatic stellate cells (PSCs) leads to the deposition of extracellular matrix proteins in the tumor environment resulting in poor vascularity. Targeting either PCCs or PSCs individually has produced mixed results, and there is currently no effective strategy to target both cell types simultaneously. Previously, we demonstrated, through in vitro cell culture experiments, that a specific gold nanoparticle-based nanoformulation containing the anti-EGFR antibody cetuximab (C225) as a targeting agent and gemcitabine as a chemotherapeutic agent effectively targets both PCCs and PSCs simultaneously. Herein, we extend our studies to test the ability of these in vitro tested nano formulations to inhibit tumor growth in an orthotopic co-implantation model of pancreatic cancer in vivo. Orthotopic tumors were established by co-implantation of equal numbers of PCCs and PSCs in the mouse pancreas. Among the various formulations tested, 5 nm gold nanoparticles coated with gemcitabine, cetuximab and poly-ethylene glycol (PEG) of molecular weight 1000 Da, which we named ACGP441000, demonstrated optimal efficacy in inhibiting tumor growth. The current study reveals an opportunity to target PCCs and PSCs simultaneously, by exploiting their overexpression of EGFR as a target, in order to inhibit pancreatic cancer growth.
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Nanopartículas Metálicas , Neoplasias Pancreáticas , Animais , Camundongos , Gencitabina , Ouro , Cetuximab/farmacologia , Desoxicitidina/farmacologia , Desoxicitidina/uso terapêutico , Distribuição Tecidual , Linhagem Celular Tumoral , Neoplasias Pancreáticas/patologia , Sistemas de Liberação de Medicamentos/métodos , Células Estreladas do Pâncreas/metabolismoRESUMO
Recent research has examined the extent to which face and voice processing are associated by virtue of the fact that both tap into a common person perception system. However, existing findings do not yet fully clarify the role of familiarity in this association. Given this, two experiments are presented that examine face-voice correlations for unfamiliar stimuli (Experiment 1) and for familiar stimuli (Experiment 2). With care being taken to use tasks that avoid floor and ceiling effects and that use realistic speech-based voice clips, the results suggested a significant positive but small-sized correlation between face and voice processing when recognizing unfamiliar individuals. In contrast, the correlation when matching familiar individuals was significant and positive, but much larger. The results supported the existing literature suggesting that face and voice processing are aligned as constituents of an overarching person perception system. However, the difference in magnitude of their association here reinforced the view that familiar and unfamiliar stimuli are processed in different ways. This likely reflects the importance of a pre-existing mental representation and cross-talk within the neural architectures when processing familiar faces and voices, and yet the reliance on more superficial stimulus-based and modality-specific analysis when processing unfamiliar faces and voices.
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BACKGROUND: A volitional help sheet (VHS) is an intervention for promoting implementation intentions. This study was the first to test the effectiveness of a VHS for increasing university students' lecture attendance. AIMS: To develop a VHS to increase university students' lecture attendance and test its effectiveness at increasing the proportion of lectures attended, and promoting the maintenance of lecture attendance, over an 11-week teaching semester. SAMPLE AND METHOD: One hundred and seventy-eight undergraduate students enrolled in a psychology degree programme were allocated at random to a VHS or active control condition. Prior to intervention, measures of goal intention to attend lectures and trait conscientiousness were collected using self-report, online questionnaires. Over the following 11-week teaching semester, attendance at synchronous (live) online lectures was measured. RESULTS: The VHS condition attended a greater proportion of lectures and maintained their lecture attendance for longer than did the active control condition. These effects were not sensitive to underlying goal intentions, although the sample means on the measures of goal intention were approaching ceiling. Trait conscientiousness increased the effects of the VHS on the proportion of lectures attended. CONCLUSIONS: VHSs constitute useful interventions for increasing and maintaining university students' lecture attendance.
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Concern over the impact of fake news on major socio-political events is growing. The use of deliberate misinformation is thought to have played a role in the outcome of the UK EU referendum, the 2016 US presidential election, and in the effectiveness of COVID-19 public health messaging. As a result, recent research has tended to focus on hyper-partisan (e.g., US politics; Democrat/Republican), person specific (e.g., Hillary Clinton/Donald Trump) content that incorporates emotive and hyperbolic language. However, in this study, we focus on an alternative form of fake news, across a variety of topics (e.g., Crime, Immigration, and Health), that avoids these characteristics, and which may therefore be more pervasive and difficult to detect. In a three-part study, we examined participants sharing intentions for fake news (including platform preference; Facebook, Twitter, Instagram, and WhatsApp), their ability to explicitly detect fake news, and whether individual differences on psychological measures of critical thinking ability, rational thinking, and emotional stability predict sharing behavior and detection ability. The results show that even our well-informed sample (political science students) were not immune to the effects of fake news, some issues (e.g., health and crime) were more likely to be shared than others (e.g., immigration), and on specific platforms (e.g., Twitter, Facebook). In addition, we show that individual differences in emotional stability appears to be a key factor in sharing behavior, while rational thinking aptitude was key to fake news detection. Taken together, this study provides novel data that can be used to support targeted fake news interventions, suggesting possible news topic, sharing behavior, and platform specific insights. Such interventions, and implications for government policy, education, and social media companies are discussed.
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[This corrects the article DOI: 10.1371/journal.pone.0246757.].
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BACKGROUND AND AIMS: Social media use has become a ubiquitous part of society, with 3.8 billion users worldwide. While research has shown that there are positive aspects to social media engagement (e.g. feelings of social connectedness and wellbeing), much of the focus has been on the negative mental health outcomes which are associated with excessive use (e.g. higher levels of depression/anxiety). While the evidence to support such negative associations is mixed, there is a growing debate within the literature as to whether excessive levels of social media use should become a clinically defined addictive behaviour. METHODS: Here we assess whether one hallmark of addiction, the priority processing of addiction related stimuli known as an 'attentional bias', is evident in a group of social media users (N = 100). Using mock iPhone displays, we test whether social media stimuli preferentially capture users' attention and whether the level of bias can be predicted by platform use (self-report, objective smartphone usage data), and whether it is associated with scores on established measures of social media engagement (SMES) and social media 'addiction' severity scales (BSNAS, SMAQ). RESULTS: Our findings do not provide support for a social media specific attentional bias. While there was a large range of individual differences in our measures of use, engagement, and 'addictive' severity, these were not predictive of, or associated with, individual differences in the magnitude of attentional capture by social media stimuli. CONCLUSIONS: More research is required before social media use can be definitively placed within an addiction framework.
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Viés de Atenção , Comportamento Aditivo , Mídias Sociais , Atenção , Comportamento Aditivo/psicologia , Humanos , SmartphoneRESUMO
The proliferation of fake news on social media is now a matter of considerable public and governmental concern. In 2016, the UK EU referendum and the US Presidential election were both marked by social media misinformation campaigns, which have subsequently reduced trust in democratic processes. More recently, during the COVID-19 pandemic, the acceptance of fake news has been shown to pose a threat to public health. Research on how to combat the false acceptance of fake news is still in its infancy. However, recent studies have started to focus on the psychological factors which might make some individuals less likely to fall for fake news. Here, we adopt that approach to assess whether individuals who show high levels of 'emotional intelligence' (EQ) are less likely to fall for fake news items. That is, are individuals who are better able to disregard the emotionally charged content of such items, better equipped to assess the veracity of the information. Using a sample of UK participants, an established measure of EQ and a novel fake news detection task, we report a significant positive relationship between individual differences in emotional intelligence and fake news detection ability. We also report a similar effect for higher levels of educational attainment, and we report some exploratory qualitative fake news judgement data. Our findings are discussed in terms of their applicability to practical short term (i.e. current Facebook user data) and medium term (i.e. emotional intelligence training) interventions which could enhance fake news detection.
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Comunicação , Inteligência Emocional , Mídias Sociais , Adolescente , Adulto , COVID-19/epidemiologia , Escolaridade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Saúde Pública , Adulto JovemRESUMO
Chronic insomnia is associated with subjective daytime cognitive dysfunction, but objective corroborative data are often lacking. In this study, we use Perceptual Load Theory to objectively assess distractibility in participants with insomnia (N = 23) compared with age- and sex-matched controls (N = 23). Following overnight supervised sleep observation, all participants completed a selective attention task which varied in the level of perceptual load and distractor congruency. The insomnia group was found to be more distracted than controls, whereas their selective attention mechanism appeared to be intact, with reduced distractor processing under high load for both groups. Insomnia symptom severity was positively correlated with participant distractibility. These findings suggest that there are insomnia-related daytime cognitive impairments that are likely to arise from compromised cognitive control rather than an ineffective selective attention mechanism. This task may be clinically useful in assessing daytime impairments, and potentially treatment response, in those with insomnia.
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Distúrbios do Início e da Manutenção do Sono , Fadiga , Humanos , SonoAssuntos
Enganação , Face , Reconhecimento Facial/fisiologia , Máscaras , Percepção Social , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Silicones , Adulto JovemRESUMO
Forgetting someone's name is a common failure of memory, and often occurs despite being able to recognise that person's face. This gives rise to the widespread view that memory for names is generally worse than memory for faces. However, this everyday error confounds stimulus class (faces vs. names) with memory task: recognition versus recall. Here we compare memory for faces and names when both are tested in the same recognition memory framework. Contrary to the common view, we find a clear advantage for names over faces. Across three experiments, we show that recognition of previously unfamiliar names exceeds recognition of previously unfamiliar faces. This advantage persists, even when the same face pictures are repeated at learning and test-a picture-memory task known to produce high levels of performance. Differential performance between names and faces disappears in recognition memory for familiar people. The results are discussed with reference to representational complexity and everyday memory errors.
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Aprendizagem por Associação , Face , Reconhecimento Facial , Rememoração Mental , Nomes , Feminino , Humanos , Masculino , Reconhecimento Visual de Modelos , Reconhecimento PsicológicoRESUMO
We investigated the relationships between individual differences in different aspects of face-identity processing, using the Glasgow Face Matching Test (GFMT) as a measure of unfamiliar face perception, the Cambridge Face Memory Test (CFMT) as a measure of new face learning, and the Before They Were Famous task (BTWF) as a measure of familiar face recognition. These measures were integrated into two separate studies examining the relationship between face processing and other tasks. For Study 1 we gathered participants' subjective ratings of their own face perception abilities. In Study 2 we used additional measures of perceptual and cognitive abilities, and personality factors to place individual differences in a broader context. Performance was significantly correlated across the three face-identity tasks in both studies, suggesting some degree of commonality of underlying mechanisms. For Study 1 the participants' self-ratings correlated poorly with performance, reaching significance only for judgements of familiar face recognition. In Study 2 there were few associations between face tasks and other measures, with task-level influences seeming to account for the small number of associations present. In general, face tasks correlated with each other, but did not show an overall relation with other perceptual, cognitive or personality tests. Our findings are consistent with the existence of a general face-perception factor, able to account for around 25% of the variance in scores. However, other relatively task-specific influences are also clearly operating.
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Our reliance on face photos for identity verification is at odds with extensive research which shows that matching pairs of unfamiliar faces is highly prone to error. This process can therefore be exploited by identity fraudsters seeking to deceive ID checkers (e.g., using a stolen passport which contains an image of a similar looking individual to deceive border control officials). In this study we build on previous work which sought to quantify the threat posed by a relatively new type of fraud: morphed passport photos. Participants were initially unaware of the presence of morphs in a series of face photo arrays and were simply asked to detect which images they thought had been digitally manipulated (i.e., "images that didn't look quite right"). All participants then received basic information on morph fraud and rudimentary guidance on how to detect such images, followed by a morph detection training task (Training Group, n = 40), or a non-face control task (Guidance Group, n = 40). Participants also completed a post-guidance/training morph detection task and the Models Face Matching Test (MFMT). Our findings show that baseline morph detection rates were poor, that morph detection training significantly improved the identification of these images over and above basic guidance, and that accuracy in the mismatch condition of the MFMT correlated with morph detection ability. The results are discussed in relation to potential countermeasures for morph-based identity fraud.
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Matching unfamiliar faces is known to be difficult, and this can give an opportunity to those engaged in identity fraud. Here we examine a relatively new form of fraud, the use of photo-ID containing a graphical morph between two faces. Such a document may look sufficiently like two people to serve as ID for both. We present two experiments with human viewers, and a third with a smartphone face recognition system. In Experiment 1, viewers were asked to match pairs of faces, without being warned that one of the pair could be a morph. They very commonly accepted a morphed face as a match. However, in Experiment 2, following very short training on morph detection, their acceptance rate fell considerably. Nevertheless, there remained large individual differences in people's ability to detect a morph. In Experiment 3 we show that a smartphone makes errors at a similar rate to 'trained' human viewers-i.e. accepting a small number of morphs as genuine ID. We discuss these results in reference to the use of face photos for security.
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Face/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Reconhecimento Psicológico/fisiologia , Adolescente , Adulto , Feminino , Humanos , Tempo de Reação/fisiologia , Adulto JovemRESUMO
Face recognition is used to prove identity across a wide variety of settings. Despite this, research consistently shows that people are typically rather poor at matching faces to photos. Some professional groups, such as police and passport officers, have been shown to perform just as poorly as the general public on standard tests of face recognition. However, face recognition skills are subject to wide individual variation, with some people showing exceptional ability-a group that has come to be known as 'super-recognisers'. The Metropolitan Police Force (London) recruits 'super-recognisers' from within its ranks, for deployment on various identification tasks. Here we test four working super-recognisers from within this police force, and ask whether they are really able to perform at levels above control groups. We consistently find that the police 'super-recognisers' perform at well above normal levels on tests of unfamiliar and familiar face matching, with degraded as well as high quality images. Recruiting employees with high levels of skill in these areas, and allocating them to relevant tasks, is an efficient way to overcome some of the known difficulties associated with unfamiliar face recognition.
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Face , Polícia , Reconhecimento Psicológico/fisiologia , Adulto , Humanos , Londres , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Tempo de Reação/fisiologiaRESUMO
Our recognition of familiar faces is excellent, and generalises across viewing conditions. However, unfamiliar face recognition is much poorer. For this reason, automatic face recognition systems might benefit from incorporating the advantages of familiarity. Here we put this to the test using the face verification system available on a popular smartphone (the Samsung Galaxy). In two experiments we tested the recognition performance of the smartphone when it was encoded with an individual's 'face-average'--a representation derived from theories of human face perception. This technique significantly improved performance for both unconstrained celebrity images (Experiment 1) and for real faces (Experiment 2): users could unlock their phones more reliably when the device stored an average of the user's face than when they stored a single image. This advantage was consistent across a wide variety of everyday viewing conditions. Furthermore, the benefit did not reduce the rejection of imposter faces. This benefit is brought about solely by consideration of suitable representations for automatic face recognition, and we argue that this is just as important as development of matching algorithms themselves. We propose that this representation could significantly improve recognition rates in everyday settings.
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Segurança Computacional , Face , Reconhecimento Visual de Modelos , Reconhecimento Psicológico , Smartphone , Adulto , Algoritmos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
Recently we reported that gold nanoparticles (AuNPs) inhibit ovarian tumor growth and metastasis in mice by reversing epithelial-mesenchymal transition (EMT). Since EMT is known to confer drug resistance to cancer cells, we wanted to investigate whether anti-EMT property of AuNP could be utilized to sensitize ovarian cancer cells to cisplatin. Herein, we report that AuNPs prevent cisplatin-induced acquired chemoresistance and stemness in ovarian cancer cells and sensitize them to cisplatin. AuNPs inhibit cisplatin induced EMT, decrease the side population cells and key stem cell markers such as ALDH1, CD44, CD133, Sox2, MDR1 and ABCG2 in ovarian cancer cells. Mechanistically, AuNPs prevent cisplatin-induced activation of Akt and NF-kB signaling axis in ovarian cancer cells that are critical for EMT, stem cell maintenance and drug resistance. In vivo, AuNPs sensitize orthotopically implanted ovarian tumor to a low dose of cisplatin and significantly inhibit tumor growth via facilitated delivery of both AuNP and cisplatin. These findings suggest that by depleting stem cell pools and inhibiting key molecular pathways gold nanoparticles sensitize ovarian cancer cells to cisplatin and may be used in combination to inhibit tumor growth and metastasis in ovarian cancer.
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Cisplatino/farmacologia , Ouro/administração & dosagem , Nanopartículas Metálicas/administração & dosagem , Neoplasias Ovarianas/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Regulação para Baixo , Sinergismo Farmacológico , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Humanos , Camundongos , Camundongos Nus , Nanopartículas , Neoplasias Ovarianas/patologia , Transdução de Sinais , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
OBJECTIVE: Increased vulnerability to extraneous distraction is a key symptom of Attention-Deficit Hyperactivity Disorder (ADHD), which may have particularly disruptive consequences. Here we apply Load Theory of attention to increase understanding of this symptom, and to explore a potential method for ameliorating it. Previous research in nonclinical populations has highlighted increased perceptual load as a means of improving the ability to focus attention and avoid distraction. The present study examines whether adults with ADHD can also benefit from conditions of high perceptual load to improve their focused attention abilities. METHOD: We tested adults with ADHD and age- and IQ-matched controls on a novel measure of irrelevant distraction under load, designed to parallel the form of distraction that is symptomatic of ADHD. During a letter search task, in which perceptual load was varied through search set size, participants were required to ignore salient yet entirely irrelevant distractors (colorful images of cartoon characters) presented infrequently (10% of trials). RESULTS: The presence of these distractors produced a significantly greater interference effect on the search RTs for the adults with ADHD compared with controls, p = .005, ηp² = .231. Perceptual load, however, significantly reduced distractor interference for the ADHD group and was as effective in reducing the elevated distractor interference in ADHD as it was for controls. CONCLUSIONS: These findings clarify the nature of the attention deficit underlying increased distraction in ADHD, and demonstrate a tangible method for overcoming it.
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Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Atenção , Percepção Visual , Adulto , Humanos , Tempo de ReaçãoRESUMO
We have experimentally studied the degradation of mode purity for light beams carrying orbital angular momentum (OAM) propagating through simulated atmospheric turbulence. The turbulence is modeled as a randomly varying phase aberration, which obeys statistics postulated by Kolmogorov turbulence theory. We introduce this simulated turbulence through the use of a phase-only spatial light modulator. Once the turbulence is introduced, the degradation in mode quality results in crosstalk between OAM modes. We study this crosstalk in OAM for 11 modes, showing that turbulence uniformly degrades the purity of all the modes within this range, irrespective of mode number.