25 research outputs found
Resistance to medical artificial intelligence is an attribute in a compensatory decision process: response to Pezzo and Beckstead (2020)
No full textIn Longoni et al. (2019), we examine how algorithm aversion influences utilization of healthcare delivered by human and
artificial intelligence providers. Pezzo and Beckstead’s (2020) commentary asks whether resistance to medical AI takes the
form of a noncompensatory decision strategy, in which a single attribute determines provider choice, or whether resistance to
medical AI is one of several attributes considered in a compensatory decision strategy. We clarify that our paper both claims
and finds that, all else equal, resistance to medical AI is one of several attributes (e.g., cost and performance) influencing
healthcare utilization decisions. In other words, resistance to medical AI is a consequential input to compensatory decisions
regarding healthcare utilization and provider choice decisions, not a noncompensatory decision strategy. People do not always
reject healthcare provided by AI, and our article makes no claim that they do
Resistance to Medical Artificial Intelligence
No full textArtificial intelligence (AI) is revolutionizing healthcare, but little is known about consumer receptivity to AI in medicine. Consumers are reluctant to utilize healthcare provided by AI in real and hypothetical choices, separate and joint evaluations. Consumers are less likely to utilize healthcare (study 1), exhibit lower reservation prices for healthcare (study 2), are less sensitive to differences in provider performance (studies 3A-3C), and derive negative utility if a provider is automated rather than human (study 4). Uniqueness neglect, a concern that AI providers are less able than human providers to account for consumers' unique characteristics and circumstances, drives consumer resistance to medical AI. Indeed, resistance to medical AI is stronger for consumers who perceive themselves to be more unique (study 5). Uniqueness neglect mediates resistance to medical AI (study 6), and is eliminated when AI provides care (a) that is framed as personalized (study 7), (b) to consumers other than the self (study 8), or (c) that only supports, rather than replaces, a decision made by a human healthcare provider (study 9). These findings make contributions to the psychology of automation and medical decision making, and suggest interventions to increase consumer acceptance of AI in medicine
Vascular Disrupting Activity of Tubulin-Binding 1,5-Diaryl-1H-imidazoles
No full textHighly cytotoxic 1,5-diaryl-1H-imidazoles were studied to clarify the relationship between cytotoxicity and activity as vascular disrupting agents (VDA). All the compounds disorganized the tubulin cytoskeleton, affected endothelial cell morphology and capillary formation in vitro, and caused vessel shutdown and tumor necrosis in vivo, thus confirming their vascular disrupting properties. Nonetheless, the substitution patterns on the imidazole ring, responsible for greater interaction energy with tubulin and higher cytotoxicity, were not associated to greater vascular disrupting activity
Sequence dependent antitumour efficacy of the vascular disrupting agent ZD6126 in combination with paclitaxel
No full textThe clinical success of small-molecule vascular disrupting agents (VDAs) depends on their combination with conventional therapies. Scheduling and sequencing remain key issues in the design of VDA-chemotherapy combination treatments. This study examined the antitumour activity of ZD6126, a microtubule destabilising VDA, in combination with paclitaxel (PTX), a microtubule- stabilising cytotoxic drug, and the influence of schedule and sequence on the efficacy of the combination. Nude mice bearing MDA-MB-435 xenografts received weekly cycles of ZD6126 (200 mg kg-1 i.p.) administered at different times before or after PTX (10, 20, and 40 mg kg-1 i.v.). ZD6126 given 2 or 24 h after PTX showed no significant benefit, a result that was attributed to a protective effect of PTX against ZD6126-induced vascular damage and tumour necrosis, a hallmark of VDA activity. Paclitaxel counteracting activity was reduced by distancing drug administrations, and ZD6126 given 72 h after PTX potentiated the VDA's antitumour activity. Schedules with ZD6126 given before PTX improved therapeutic activity, which was paralleled by a VDA-induced increase in cell proliferation in the viable tumour tissue. Paclitaxel given 72 h after ZD6126 yielded the best response (50% tumours regressing). A single treatment with ZD6126 followed by weekly administration of PTX was sufficient to achieve a similar response (57% remissions). These findings show that schedule, sequence and timing are crucial in determining the antitumour efficacy of PTX in combination with ZD6126. Induction of tumour necrosis and increased proliferation in the remaining viable tumour tissue could be exploited as readouts to optimise schedules and maximise therapeutic efficacy
A worldline approach to colored particles
No full textRelativistic particle actions are a useful tool to describe quantum field theory effective actions using a string-inspired first-quantized approach. Here we describe how to employ suitable particle actions in the computation of the scalar contribution to the one-loop gluon effective action. We use the well-known method of introducing auxiliary variables that create the color degrees of freedom. In a path integral they implement automatically the path ordering needed to ensure gauge invariance. It is known that the color degrees of freedom introduced this way form a reducible representation of the gauge group. We describe a method of projecting onto the fundamental representation (or any other chosen irrep, if desired) of the gauge group. Previously, we have discussed the case of anticommuting auxiliary variables. Choosing them to be in the fundamental representation allows to obtain, without any extra effort, also the situation in which the color is given by any antisymmetric tensor product of the fundamental. Here, we describe the novel case of bosonic auxiliary variables. They can be used equivalently for creating the color charges in the fundamental representation. In addition one gets, as a byproduct, the cases where the particle can have the color sitting in any symmetric tensor product of the fundamental. This is obtained by tuning to a different value a Chern Simons coupling, present in the model, which controls how the projection is achieved
On Braggarts and Gossips: Why Consumers Generate Positive but Transmit Negative Word of Mouth
No full textWe propose that consumers tend to generate positive word-of-mouth, by talking about their positive experiences with products, but
transmit negative word-of-mouth, by talking about negative experiences occurred to others. We show that the basic human motive to
self-enhance can parsimoniously explain both generation of positive and transmission of negative word-of-mouth
The double copy of maximal supersymmetry in D = 4
No full textAbstract We realize off-shell, local and gauge invariant N = 8 supergravity in D = 4, to cubic order in fields, as the double copy of N = 4 super Yang-Mills theory (SYM). Employing the homotopy algebra approach, we show that, thanks to a redundant formulation for the fermionic fields, the kinematic algebra K of N = 4 SYM is compatible with an action of the global supersymmetry algebra. The double copy space is then a subspace of K ⨂ K ~ that inherits an L ∞ algebra on which the two copies of the N = 4 action combine into an action of the N = 8 supersymmetry algebra, with a corresponding enhancement of the R-symmetry group to SU(8)
Reduced expression of the ROCK inhibitor Rnd3 is associated with increased invasiveness and metastatic potential in mesenchymal tumor cells.
No full textBackgroundMesenchymal and amoeboid movements are two important mechanisms adopted by cancer cells to invade the surrounding environment. Mesenchymal movement depends on extracellular matrix protease activity, amoeboid movement on the RhoA-dependent kinase ROCK. Cancer cells can switch from one mechanism to the other in response to different stimuli, limiting the efficacy of antimetastatic therapies.Methodology and principal findingsWe investigated the acquisition and molecular regulation of the invasion capacity of neoplastically transformed human fibroblasts, which were able to induce sarcomas and metastases when injected into immunocompromised mice. We found that neoplastic transformation was associated with a change in cell morphology (from fibroblastic to polygonal), a reorganization of the actin cytoskeleton, a decrease in the expression of several matrix metalloproteases and increases in cell motility and invasiveness. In a three-dimensional environment, sarcomagenic cells showed a spherical morphology with cortical actin rings, suggesting a switch from mesenchymal to amoeboid movement. Accordingly, cell invasion decreased after treatment with the ROCK inhibitor Y27632, but not with the matrix protease inhibitor Ro 28-2653. The increased invasiveness of tumorigenic cells was associated with reduced expression of Rnd3 (also known as RhoE), a cellular inhibitor of ROCK. Indeed, ectopic Rnd3 expression reduced their invasive ability in vitro and their metastatic potential in vivo.ConclusionsThese results indicate that, during neoplastic transformation, cells of mesenchymal origin can switch from a mesenchymal mode of movement to an amoeboid one. In addition, they point to Rnd3 as a possible regulator of mesenchymal tumor cell invasion and to ROCK as a potential therapeutic target for sarcomas
