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Disks around young free-floating planetary-mass objects:ultradeep <i>Spitzer</i> imaging of IC348
No full textProtoplanetary discs have been found around free-floating objects with masses comparable to those of giant planets. The frequency and properties of these discs around planetary-mass objects are still debated. Here, we present ultradeep mid-infrared images for the young cluster IC348, obtained through stacking of time-series images from Spitzer. We measure fluxes at 3.6 and 4.5 μm for known free-floating planetary-mass objects (FFPMOs, spectral type M9 or later) in this cluster. By comparing the observed infrared spectral energy distributions with photospheric templates, we identify six planetary-mass objects with discs, plus three, which may or may not have a disc. This corresponds to a disc fraction of 46-12+13 per cent. The disc fraction among planetary-mass objects is comparable to more massive brown dwarfs. We show the disc fraction among FFPMOs as a function of age, demonstrating that these objects retain discs for several million years, similar to low-mass stars and brown dwarfs
The birth of spatial transgression:genealogies and regulatory instruments in the use of facial recognition technologies in the UK
No full textThe chapter grapples with the use of Facial Recognition Technologies (FRTs) in the UK. We commence with a perambulation in the literature that has studied surveillance transformations and trace the shifting meanings and nature of privacy in the urban context. We position these cutting-edge facial recognition, surveillance, and location-based technologies in a historical context before introducing the notion of “spatial transgression”, a notion reflecting the sedimentary nature of the blending of digital and physical space. The chapter concludes by raising questions around the means and capacities for resisting spatial transgression as spearheaded by the proliferation of FRTs in urban public space
Meaning making in an art context affects semantic distance:the case of semantic inconsistencies in written language
No full textWhen people know they are encountering art, that awareness may change how they interpret what they experience. However, it is not clear how engaging with art affects cognition in everyday life. This collection of studies investigates how meaning-making in an art context influences semantic distance. Semantic distance involves connecting weakly-related concepts and plays an important role in cognitive processes such as memory and creativity. Across four studies, participants attributed meaning to semantically incongruent sentences («Most cats see well at court”), believing either that they were or were not created by artists. We then measured the effects on semantic distance using a network-based approach (Studies 1 and 2) and a sensorimotor distance-based approach (Studies 3 and 4). In Studies 1 and 2, participants decided whether two words were related or unrelated in word pairs with varying path lengths (e.g., ashtray-smoking, sea-survey). In Studies 3 and 4, participants made similar decisions for word pairs that were either closely associated ('to see' – 'colour') or distantly associated ('to see' – 'song') with different sensory modalities. In Studies 1 and 3, both prime and target words were presented without time limitations, and participants in the art condition evaluated distant word pairs as more strongly associated compared to those in the baseline condition. In Studies 2 and 4, participants performed similar tasks, but prime and target words appeared only briefly, reducing the influence of top-down deliberation processes and decreasing the observed effects. These findings suggest that meaning-making in an art context facilitates connecting distant concepts, offering insights into how art impacts cognition in everyday life
Genome-wide association neural networks identify genes linked to family history of Alzheimer's disease
No full textAugmenting traditional genome-wide association studies (GWAS) with advanced machine learning algorithms can allow the detection of novel signals in available cohorts. We introduce “genome-wide association neural networks (GWANN)” a novel approach that uses neural networks (NNs) to perform a gene-level association study with family history of Alzheimer’s disease (AD). In UK Biobank, we defined cases (n = 42 110) as those with AD or family history of AD and sampled an equal number of controls. The data was split into an 80:20 ratio of training and testing samples, and GWANN was trained on the former followed by identifying associated genes using its performance on the latter. Our method identified 18 genes to be associated with family history of AD. APOE, BIN1, SORL1, ADAM10, APH1B, and SPI1 have been identified by previous AD GWAS. Among the 12 new genes, PCDH9, NRG3, ROR1, LINGO2, SMYD3, and LRRC7 have been associated with neurofibrillary tangles or phosphorylated tau in previous studies. Furthermore, there is evidence for differential transcriptomic or proteomic expression between AD and healthy brains for 10 of the 12 new genes. A series of post hoc analyses resulted in a significantly enriched protein–protein interaction network (P-value < 1 × 10−16), and enrichment of relevant disease and biological pathways such as focal adhesion (P-value = 1 × 10−4), extracellular matrix organization (P-value = 1 × 10−4), Hippo signaling (P-value = 7 × 10−4), Alzheimer’s disease (P-value = 3 × 10−4), and impaired cognition (P-value = 4 × 10−3). Applying NNs for GWAS illustrates their potential to complement existing algorithms and methods and enable the discovery of new associations without the need to expand existing cohorts
The effect of exploratory trademark strategy on corporate cash holdings
No full textThe theoretical and empirical focus of this study is the relationship between exploratory trademark strategy and corporate cash holdings, which is rarely explored in the literature. Using data from Chinese listed firms over the 2005–2021 period, we find a positive correlation between firms' exploratory trademark strategies and their cash holdings. Our cross-sectional analyses reveal that this effect is particularly strong in firms facing greater environmental uncertainty, higher financial constraints, and weaker corporate governance. We also find that exploratory trademark strategies drive increased investment in brand capital and R&D, with firms prioritizing strategic investments over cash dividends. These findings highlight the dual role of trademarks as both market assets and key elements of financial management, which prompt firms to maintain higher cash reserves to support their long-term strategic objectives
A white-box false positive adversarial attack method on contrastive loss based offline handwritten signature verification models
No full textIn this paper, we tackle the challenge of white-box false positive adversarial attacks on contrastive loss based offline handwritten signature verification models. We propose a novel attack method that treats the attack as a style transfer between closely related but distinct writing styles. To guide the generation of deceptive images, we introduce two new loss functions that enhance the attack success rate by perturbing the Euclidean distance between the embedding vectors of the original and synthesized samples, while ensuring minimal perturbations by reducing the difference between the generated image and the original image. Our method demonstrates state-of-the-art performance in white-box attacks on contrastive loss based offline handwritten signature verification models, as evidenced by our experiments. The key contributions of this paper include a novel false positive attack method, two new loss functions, effective style transfer in handwriting styles, and superior performance in white-box false positive attacks compared to other white-box attack methods
Homeownership habitus and residential practice of highly-skilled Chinese migrants in the Netherlands
No full textThis paper proposes a “homeownership habitus” concept to understand the residential practice of highly-skilled young Chinese migrants in the Netherlands. Using 41 interviews, we show how and why they typically become homeowners soon after securing stable employment. Even without planning to stay in the Netherlands long-term, buying properties was taken for granted, sanctioned by the Chinese value framework whereby homeownership is not only a status-marker and rational economic choice, but integral to adulthood transitions. Homeownership was often enabled by familial intergenerational support, also functioning as a transnational investment strategy. Such rapid tenure transition included spatial strategies to buy in “good” suburban locations or more affordable lower-reputation localities. The historic city centres of Amsterdam and Utrecht were deemed expensive and housing stock old, while Rotterdam’s modern city centre was popular among them. This paper contributes to literature on highly-skilled Chinese in Western cities, residential practice of migrants and transnational materialization of habitus across fields
Meddlesome blame and negotiating standing
No full textBlaming others for things that are not our business can attract charges of meddling and corresponding dismissals of blame. Such charges are contentious because the content and applicability conditions of anti-meddling norms can be difficult to specify. An unappreciated reason they can be contentious is that it is often not settled in advance whether some wrongdoing is or is not the business of a would-be blamer. Rather than pointing out violation of a pre-established anti-meddling norm, charges of meddling may sometimes be aiming to put such a norm in place. Grounds of anti-meddling norms, including privacy, intimacy, and respect for victims, support giving those involved significant latitude to set their own boundaries on appropriate blame. This brings out the more general point that norms of blame, including standing norms, are often up for negotiation, and dismissals of blame can be moves in such a negotiation of trying to establish boundaries on blame, rather than merely pointing out violations of pre-established boundaries
ATP1A3 dysfunction causes motor hyperexcitability and afterhyperpolarization loss in a dystonia model
No full textMutations in the gene encoding the alpha3 Na+/K+-ATPase isoform (ATP1A3) lead to movement disorders that manifest with dystonia, a common neurological symptom with many different origins, but for which the underlying molecular mechanisms remain poorly understood. We have generated an ATP1A3 mutant mouse that displays motor impairments and a hyperexcitable motor phenotype compatible with dystonia. We show that neurons harboring this mutation are compromised in their ability to extrude raised levels of intracellular sodium, highlighting a profound deficit in neuronal sodium homeostasis. We show that the spinal motor network in ATP1A3 mutant mice has a reduced responsiveness to activity-dependent rises in intracellular sodium and that this is accompanied by loss of the Na+/K+-ATPase-mediated afterhyperpolarization in motor neurons. Taken together, our data support that the alpha3 Na+/K+-ATPase is important for cellular and spinal motor network homeostasis. These insights suggest that it may be useful to consider ways to compensate for this loss of a critical afterhyperpolarization-dependent control of neuronal excitability when developing future therapies for dystonia