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1. Structured and Balanced Multicomponent and Multilayer Neural Networks

   https://doi.org/10.1137/24M1675990  

   Zhang, Shijun; Zhao, Hongkai; Zhong, Yimin; Zhou, Haomin (October 2025, SIAM Journal on Scientific Computing)

   In this work, we propose a balanced multicomponent and multilayer neural network (MMNN) structure to accurately and efficiently approximate functions with complex features in terms of both degrees of freedom and computational cost. The main idea is inspired by a multicomponent approach in which each component can be effectively approximated by a single-layer network, combined with a multilayer decomposition strategy to capture the complexity of the target function. Although MMNNs can be viewed as a simple modification of fully connected neural networks (FCNNs) or multilayer perceptrons (MLPs) by introducing balanced multicomponent structures, they achieve a significant reduction in training parameters, a much more efficient training process, and improved accuracy compared to FCNNs or MLPs. Extensive numerical experiments demonstrate the effectiveness of MMNNs in approximating highly oscillatory functions and their ability to automatically adapt to localized features. Our code and implementations are available at GitHub. 

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2. Policy Learning and Policy Change: Katrina, Ike and Post-Disaster Housing

   Sapat, A.; Li, Y.; Mitchell, C.; Esnard, A-M. (January 2011, International journal of mass emergencies and disasters)

   Hurricane Katrina has spawned a great deal of research on various issues, including problems and failures in disaster preparation, response and recovery. Less attention has been paid however, to scholarly analyses of policy learning and change with regard to post-disaster housing. The focus of this paper is to fill that gap by analyzing the extent of policy learning and policy changes adopted after Katrina, and by examining the response three years later to Hurricane Ike. We reviewed key legislation and used theoretical insights drawn from the policy literature as a framework for examining post-disaster policy changes and outcomes. We find that as a policy issue, post-disaster housing continues to be a ‘wicked’ and ‘messy’ policy problem, exacerbated by unrealistic expectations of governmental agencies, and characterized by a weak advocacy base. To this end, we offer some policy and planning considerations in our conclusion. 

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3. Synthetic Routes to, Stabilities and Transformations of, and Characterization of (Carbamoyl)disulfanyl Chlorides and Related Compounds1,2

   https://doi.org/10.3390/molecules30193892  

   Goldblatt, Phillip T; Thompson, Tracy R; Brennessel, William W; Smith, Thomas G; Schrader, Alex M; Goebel, Erik S; Henley, Madeleine J; Lovstedt, Alex; Young, Victor G; Barany, George (October 2025, Molecules)

   Previously unobserved (carbamoyl)disulfanyl chlorides were prepared by (i) addition of limiting aromatic secondary amine to (chlorocarbonyl)disulfanyl chloride; (ii) Harris reactions of sulfur dichloride with appropriate O-alkyl N-methyl-N-arylthiocarbamates; and (iii) regiospecific chlorolysis of bis(N-methyl-N-arylcarbamoyl)disulfanes. The newly synthesized unstable species were observed in situ by 1H NMR and were trapped with alkenes, thiocarbamates, and thiols using methods precedented by the chemistry of analogous (carbamoyl)sulfenyl chlorides. Furthermore, each of the trapped products was synthesized by an alternate route, reinforcing conclusions about their structures. While (N-methyl-N-phenylcarbamoyl)disulfanyl chloride was unstable and decomposed quickly or cyclized intramolecularly, introduction of the N,2,6-trimethylphenyl moiety led to significantly improved stability. As part of this study, an interesting, unexpectedly stable 1,2,4-dithiazinone was discovered and its structure was established by X-ray crystallography. The new heterocycle, with its twisted out-of-plane disulfide bond in a six-membered ring, readily donated a sulfur atom to triphenylphosphine; this reaction resulted in the formation of triphenylphosphine sulfide, along with the corresponding highly stable heterocycle in which the single sulfur that remains is part of a planar five-membered ring, fused to a co-planar aryl moiety. 

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4. Simulations and symmetries

   https://doi.org/10.1093/mnras/staa251  

   Modi, Chirag; Chen, Shi-Fan; White, Martin (March 2020, Monthly Notices of the Royal Astronomical Society)

   ABSTRACT We investigate the range of applicability of a model for the real-space power spectrum based on N-body dynamics and a (quadratic) Lagrangian bias expansion. This combination uses the highly accurate particle displacements that can be efficiently achieved by modern N-body methods with a symmetries-based bias expansion which describes the clustering of any tracer on large scales. We show that at low redshifts, and for moderately biased tracers, the substitution of N-body-determined dynamics improves over an equivalent model using perturbation theory by more than a factor of two in scale, while at high redshifts and for highly biased tracers the gains are more modest. This hybrid approach lends itself well to emulation. By removing the need to identify haloes and subhaloes, and by not requiring any galaxy-formation-related parameters to be included, the emulation task is significantly simplified at the cost of modelling a more limited range in scale. 

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5. Managerial and Professional Skills and Dispositions from Professionals’ Interviews

   https://doi.org/10.1145/3537674.3554751  

   Duan, Suzhen; Exter, Marisa; Tagare, Deepti; Sabin, Mihaela (September 2022, Proceedings of the 23rd Annual Conference on Information Technology Education)

   Employability should be a primary objective for computing programs, as the majority of IT and other computing graduates go to work in industry upon graduation. Furthermore, students want to be prepared for a career, not just an entry-level job. However, literature has shown a gap between employers’ needs and undergraduates’ preparation in non-technical areas. Competencies (skills, knowledge, and dispositions) can be a common language used by both employers and educators. The more we learn about competencies employers expect, the more we can ensure programs match their expectations. This study focuses on competencies required by managers, by interviewing ten directors/managers, project managers, and product managers who had prior experience in computing-related roles. Each was asked to discuss competencies most important to their current position. Emerging themes identified the most important managerial skills (project management, evaluation of candidates, mentorship, managers’ own technical skills and knowledge, adjusting management style as needed, and appropriately assigning team members), professional skills (communication, problem solving, and relationship building), and dispositions (lifelong learning; adaptability/flexibility; being self-driven; self-awareness; being helpful, positive and pleasant; valuing communication and collaboration; having passion for technical work; and perseverance). Implications for education are discussed. This study is part of a larger NSF-funded project related to investigating the competencies required by computing professionals, and the design of educational resources to promote the development of these competencies. 

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