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Is dogs’ tendency to follow human misleading communicative cues influenced by humans’ auditory perspective?
No full textStudying Theory of Mind in non-verbal populations requires designing tasks that address the distinction between responding based on directly perceivable cues and additionally inferring others’ mental states. We designed and pre-registered an auditory version of a non-verbal change-of-location task, to investigate whether dogs are sensitive to a human communicator’s mental states about the location of food. With control conditions we ruled out alternative cognitive processes such as associative learning. Dogs (N = 240) could witness that food was hidden first in one opaque bucket (A) and then relocated to a second opaque bucket (B) by an experimenter. Before being allowed to retrieve the food from one of the buckets, dogs received a misleading suggestion (A) from the communicator, who could not see the scene. In all conditions, the communicator could hear food being hidden in A, due to the presence of bells on the lid of this bucket. We manipulated whether she could also hear that food was removed from A and relocated to B (true belief) or not (silent bells on B, leading to her false belief). Importantly, in both conditions the communicator behaved identically (present in the room, suggesting A). Dogs’ responses were not statistically different from those of a previous study using a similar change-of-location task in the visual domain (Lonardo et al. 288(1955), 2021, https://doi.org/10.1098/rspb.2021.0906). Dogs’ choices in the present study, however, did not differ significantly across conditions, suggesting that any auditory perspective-taking ability they might possess did not have a sufficiently large effect to be detected in this stud
Fermion-Selective Tests of New Physics with the Bound-Electron g Factor
No full textThe use of high-precision measurements of the g factor of single-electron ions is considered as a detailed probe for physics beyond the standard model. The contribution of the exchange of a hypothetical force- carrying scalar boson to the g factor is calculated for the ground state of H-like ions and used to derive bounds on the parameters of that force. Similarly to the isotope shift, we employ the nuclide shift, i.e., the difference for elements with different proton and/or neutron numbers, in order to increase the experimental sensitivity to the new physics contribution. In particular we find, combining available measurements with current precision with different ions, that the coupling constant for the interaction between an electron and a proton can be constrained up to 3 orders of magnitude better than with the best current atomic data and theory
Square-Planar Ruthenium Alkylidyne Complexes Undergo Stepwise Rather Than Concerted [2 + 2] Cycloadditions with Alkynes
No full textA new entry into square-planar, formally d4-configured ruthenium alkylidyne complexes is disclosed, using p-tolyl(trimethylsilyl)diazomethane as a convenient and safe alkylidyne synthon. The method furnished complex 12 supported by an electron-rich PNP-pincer ligand, which undergoes remarkably facile [2 + 2] cycloaddition with electron-rich, electron-deficient, and strained alkynes; these reactions represent the first examples of metallacyclobutadiene formation by a d4-configured transition metal alkylidyne complex. Strikingly, however, the cycloadditions proceed by a stepwise mechanism, which stands in marked contrast to the concerted pathway entertained by all prototypical d0 and d2 Schrock-type alkylidynes, including the molybdenum, tungsten, and rhenium complexes that currently dominate the field of alkyne metathesis. In essence, it is the non-bonding lone pair forming the largely metal-centered HOMO of significant dz2 character that accounts for this unorthodox behavior. The newly gained insight into this key reactivity determinant also allows the few other known reactions of formally d4-configured alkylidene complexes previously described in the literature to be explained and will empower further explorations of their chemistry
What Firms Actually Lose (and Gain) from Extreme Weather Event Impacts
No full textClimate change is increasing the severity of extreme weather events, posing substantial risks for firms, investors, and the economy. Although quantifying such risks has become increasingly important, existing approaches for estimating the impacts from extreme weather events face major limitations. Here, we propose a novel approach to identify and categorize firm-level impacts of extreme weather events from public corporate filings. Using large language models, we analyze 1.7 million filings from all publicly listed US firms (2005-2024), map identified impacts to 286 specific extreme weather events, and classify them by impact channels (direct asset vs. indirect economic flows) and directionalities (positive vs. negative). We identify 13,277 firm-event impacts and estimate that negative impacts caused a cumulative average abnormal stock return of -2.36% per event. The total firm value losses accumulate to 327 billion USD. The highest losses are caused by severe storms and tropical cyclones and experienced by firms in manufacturing and finance. For some sectors, such as retail and construction, we find that returns recover quickly and even turn positive, potentially due to a rebound in demand after the events. Our approach allows for a systematic, firm-level quantification of physical climate impacts, enabling informed risk assessments and adaptation strategies with high granularity
Performance evaluation of deep-ultraviolet laser-assisted Invizo 6000 and near-ultraviolet laser-assisted LEAP 5000 for a range of material systems
No full textEvidentiary value of tooth presence/absence patterns for human identification
No full textHuman identification through comparison of dental records is a well-established and widely accepted forensic method, particularly valuable in mass casualty incidents. While restorative treatments often provide strong points of comparison, their absence limits evidentiary value and increases reliance on morphological features. Patterns of tooth presence and absence can serve as comparative data; however, the lack of large-scale reference databases restricts the application of statistical probability to these patterns. This study examined dental data from 1343 deceased individuals from historic casework to assess the frequency of tooth presence/absence patterns. The findings showed that, although certain patterns occurred repeatedly, a substantial proportion of individuals displayed unique combinations not observed elsewhere in the sample. The analysis also demonstrated relationships between missing teeth and confirmed the correlation between overall tooth count and age. These findings support the utility of tooth presence/absence patterns as a comparative feature in forensic identification. Nonetheless, population differences and sample size constraints highlight the need for expanded research to establish broader statistical validity
