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A 2022 keynote for the ACM History Committee on "Why SIG History Matters: New Data on Gender Bias in ACM's Founding SIGs 1970-2000" presented new data describing women's participation as research-article authors in 13 early ACM Special Interest Groups, finding significant growth in women's participation across 1970-2000 and, additionally, remarkable differences in women's participation between the SIGs. That presentation built on several earlier publications that developed a research method for assessing the number of women computer scientists that [a] are chronologically prior to the availability of the Bureau of Labor Statistics (BLS) data on women in the IT workforce; and [b] permit focused investigation of varied sub-fields within computing. This present report expands on these earlier articles, and their evolving research method, connecting them to the ACM SIG Heritage presentation. It also outlines some of the choices and considerations made in developing and refining "mixed methods" research (using both quantitative and qualitative approaches) as well as extensions of the research being currently explored., Comment: 13 pages, 6 figures

This paper investigates the relationship between extensional and shear viscosity of low-viscosity power-law fluids. We showed the first experimental evidence of the conditions satisfying the same power exponents for extensional and shear viscosity, as indicated by the Carreau model. The extensional and shear viscosity are respectively measured by capillary breakup extensional rheometry dripping-onto-substrate (CaBER-DoS) and by a shear rheometer for various Ohnesorge number Oh. The viscosity ranges measured were about O(10^0) to O(10^4) mPas for shear viscosity and O(10^1) to O(10^3) mPas for extensional viscosity. Our experimental results show that, at least for the range of Oh > 1, the power-law expression for the liquid filament radius, extensional viscosity, and shear viscosity holds, even for low-viscosity fluids.

A new dataset (N = 7,456) analyzes women's research authorship in the Association for Computing Machinery's founding 13 Special Interest Groups or SIGs, a proxy for computer science. ACM SIGs expanded during 1970-2000; each experienced increasing women's authorship. But diversity abounds. Several SIGs had fewer than 10% women authors while SIGUCCS (university computing centers) exceeded 40%. Three SIGs experienced accelerating growth in women's authorship; most, including a composite ACM, had decelerating growth. This research may encourage reform efforts, often focusing on general education or workforce factors (across the entity of "computer science"), to examine under-studied dynamics within computer science that shaped changes in women's participation., Comment: 27 pages, 5 figures, 1 table

Lov\'{a}sz conjectured that every connected vertex-transitive graph contains a hamilton path in 1970. First we reveal the structure of connected vertex-transitive graphs with an odd number of vertices. Then we prove that every connected vertex-transitive graph with an odd number of vertices is hamiltonian.

A versatile method for angle-resolved photoemission spectra (ARPES) calculations is reported within the one-step model of photoemission. The initial states are obtained from a repeated-slab calculation using the projector-augmented wave (PAW) method. ARPES final states are constructed by matching the repeated-slab eigenstates of positive energy with free electron states that satisfy the time-reversed low-energy electron diffraction boundary conditions. Nonphysical solutions of the matching equations, which do not respect the flux conservation, are discarded. The method is applied to surface-normal photoemission from graphene as a function of photon energy from threshold up to 100 eV. The results are compared with independently performed multiple scattering calculations and very good agreement is obtained, provided that the photoemission matrix elements are computed with all-electron waves reconstructed from the PAW pseudo-waves. However, if the pseudo-waves are used directly, the relative intensity between $\sigma$- and $\pi$-band emission is wrong by an order of magnitude. The graphene ARPES intensity has a strong photon energy dependence including resonances. The normal emission spectrum from the $\pi$-band shows a hitherto unreported, sharp resonance at a photon energy of 31 eV. The resonance is due to a 2$D$ interband transitions and highlights the importance of matrix element effects beyond the final state plane-wave approximation.

We investigate the influence of the environment on the evolution of barred and unbarred disc galaxies with a mass $>10^{10}\Msun$ from z=1 down to z=0, employing the TNG50 magnetic-hydrodynamical simulation. We find that 49% of z=1 disc galaxies undergoes a morphological transformation, transitioning into either a lenticular or spheroidal, while the other 51% retains the massive disc. The morphological alteration is mostly influenced by the environment. Lenticular and spheroidal galaxies tend to exist in denser environments and have more frequent mergers compared to disc galaxies. We find that over half of the barred galaxies (60.2%) retain the bar structure and have experienced fewer mergers compared to those galaxies that lose their bars (5.6%). These latter ones start with weaker and shorter bars at z=1 influenced by tidal interactions and are frequently observed in more populated areas. Additionally, our study reveals that less than 20% of unbarred galaxies will never develop a bar and exhibit the quietest merger history. Unbarred galaxies that experience bar formation after z=1 exhibit more frequent instances of merging events. Furthermore, tidal interactions with a close companion may account for bar formation in at least one-third of the cases. Our findings highlight that stable bars are prevalent in disc galaxies. Bar evolution may nonetheless be affected by the environment. Interactions with nearby companions or tidal forces caused by mergers have the capacity to disrupt the disc. This perturbance may materialise as the dissolution of the bar, the formation of a bar, or, in its most severe form, the complete destruction of the disc, resulting in morphological transformation. Bars that are weak and short at z=1 and undergo major or minor mergers may eventually dissolve, whereas unbarred galaxies that enter crowded environments or experience a merger may develop a bar., Comment: 20 pages, 18 Figures, accepted for publication in A&A with language corrections and updates in some Figures

Independently estimating pixel values in Monte Carlo rendering results in a perceptually sub-optimal white-noise distribution of error in image space. Recent works have shown that perceptual fidelity can be improved significantly by distributing pixel error as blue noise instead. Most such works have focused on static images, ignoring the temporal perceptual effects of animation display. We extend prior formulations to simultaneously consider the spatial and temporal domains, and perform an analysis to motivate a perceptually better spatio-temporal error distribution. We then propose a practical error optimization algorithm for spatio-temporal rendering and demonstrate its effectiveness in various configurations.

Comment on Herbert Bruderer's recent CACM contribution, providing additional citations to recent publications on Ada Lovelace and suggesting a correction to his conclusions., Comment: 2 pages

Conventional photoemission orbital tomography based on Fourier iterative method enables us to extract a projected two-dimensional (2D) molecular orbital from a 2D photoelectron momentum map (PMM) of planar $\pi$-conjugated molecules in a single-orientation system, while not in a multi-orientation system. In this work, we demonstrate photoemission orbital tomography for $\pi$-conjugated molecules with a tight-binding ansatz (linear combination of atomic orbitals). We analyze 2D PMMs of single-orientation pentacene/Ag(110) and multi-orientation 3,4,9,10-perylenetetracarboxylic dianhydride/Ag(110) and reproduce their three-dimensional highest occupied molecular orbitals. We demonstrate that the PhaseLift algorithm can be used to analyze PMM including experimental or theoretical uncertainties. With the 2D PMM for pentacene, we simultaneously optimized the structure and the molecular orbital. The present approach enables us to extract the three-dimensional orbitals and structures of existing materials., Comment: The final version

Given the concerns around the existing subjective and objective policy evaluation approaches, this study proposes a new combined subjective-objective policy evaluation approach to choose better policy that reflects the will of citizens and is backed up by objective facts. Subjective approaches, such as the Life Satisfaction Approach and the Contingent Valuation Method, convert subjectivity into economic value, raising the question whether a higher economic value really accords with what citizens want. Objective policy evaluation approaches, such as Evidence Based Policy Making and Multi-Agent-Based Simulation, do not take subjectivity into account, making it difficult to choose from diverse and pluralistic candidate policies. The proposed approach establishes a subjective target function based on a multiple regression analysis of the results of a residents questionnaire survey, and uses MABS to calculate the objective evaluation indices for a number of candidate policies. Next, a new subjective-objective coupling target function, combining the explanatory variables of the subjective target function with objective evaluation indices, is set up, optimized to select the preferred policies from numerous candidates. To evaluate this approach, we conducted a verification of renewable energy introduction policies at Takaharu Town in Miyazaki Prefecture, Japan. The results show a good potential for using a new subjective-objective coupling target function to select policies consistent with the residents values for well-being from 20,000 policy candidates for social, ecological, and economic values obtained in MABS. Using the new approach to compare several policies enables concrete expression of the will of stakeholders with diverse values, and contributes to constructive discussions and consensus-building.

Function is dynamic and originates at atomic interfaces. Combining the degrees of freedom of molecules with the peculiar properties of 2D quantum materials can create novel functionality. Here, we report the manipulation and ultrafast imaging of a unidirectional gearing motion in molecules on a 2D quantum material. To visualize and disentangle the intertwined structural and electronic dynamics of such a hybrid interface, we record a 'full molecular movie' by imaging the atomic positions, the evolution of the molecular orbital wavefunctions and the modification of electronic states of the substrate. In a multimodal investigation in a single setup, we disentangle dynamics in valence and core electrons of both the molecule and the surface with femtosecond and sub-{\aa}ngstr\"om precision. The ultrafast rotational motion is fueled by the transfer of hot holes into the molecules that results in 'supercharging' of the film. As hot carriers move through the interface, we track a transient modification of the frontier molecular orbitals and observe a chiral symmetry breaking associated with local structural rearrangements. Our calculations show that the 'supercharging' changes the interfacial potential energy landscape and triggers the gearing motion. The experiment offers all-in-one imaging of the electronic, molecular orbital, chemical and structural dynamics during the flow of charge and energy across the hybrid interface. Our approach provides detailed dynamical information on the mechanism underlying surface-adsorbed molecular gears and enables tailoring novel functionalities in hybrid active matter., Comment: 19 pages, 6 figures

In this work we present a deep learning approach to conduct hypothesis-free, transcriptomics-based matching of drugs for diseases. Our proposed neural network architecture is trained on approved drug-disease indications, taking as input the relevant disease and drug differential gene expression profiles, and learns to identify novel indications. We assemble an evaluation dataset of disease-drug indications spanning 68 diseases and evaluate in silico our approach against the most widely used transcriptomics-based matching baselines, CMap and the Characteristic Direction. Our results show a more than 200% improvement over both baselines in terms of standard retrieval metrics. We further showcase our model's ability to capture different genes' expressions interactions among drugs and diseases. We provide our trained models, data and code to predict with them at https://github.com/healx/dgem-nn-public.

We address the problem of motion planning for four-way intersection crossings with right-of-ways. Road safety typically assigns liability to the follower in rear-end collisions and to the approaching vehicle required to yield in side crashes. As an alternative to previous models based on heuristic state machines, we propose a planning framework which changes the prediction model of other cars (e.g. their prototypical accelerations and decelerations) depending on the given longitudinal or lateral priority rules. Combined with a state-of-the-art trajectory optimization approach ROPT (Risk Optimization Method) this allows to find ego velocity profiles minimizing risks from curves and all involved vehicles while maximizing utility (needed time to arrive at a goal) and comfort (change and duration of acceleration) under the presence of regulatory conditions. Analytical and statistical evaluations show that our method is able to follow right-of-ways for a wide range of other vehicle behaviors and path geometries. Even when the other cars drive in a non-priority-compliant way, ROPT achieves good risk-comfort tradeoffs.

This chapter makes needed corrections to an unduly negative scholarly view of Ada Lovelace. Credit between Lovelace and Babbage is not a zero-sum game, where any credit added to Lovelace somehow detracts from Babbage. Ample evidence indicates Babbage and Lovelace each had important contributions to the famous 1843 Sketch of Babbage's Analytical Engine and the accompanying Notes. Further, Lovelace's correspondence with two highly accomplished figures in 19th century mathematics, Charles Babbage and Augustus De Morgan, establish her mathematical background and sophistication. Babbage and Lovelace's treatment of the Bernoulli numbers in Note 'G' spotlights this aspect of their collaboration. Finally, while acknowledging significant definitional problems in calling Lovelace the world's "first computer programmer," I affirm that Lovelace created an elemental sequence of instructions -- that is, an algorithm -- for computing the series of Bernoulli numbers., Comment: 20 pages, 4 figures