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1. On p-Group Isomorphism: search-to-decision, counting-to-decision, and nilpotency class reductions via tensors

   https://doi.org/10.1145/3625308  

   Grochow, Joshua A.; Qiao, Youming (September 2023, ACM Transactions on Computation Theory)

   In this paper we study some classical complexity-theoretic questions regarding GroupIsomorphism(GpI). We focus onp-groups (groups of prime power order) with oddp, which are believed to be a bottleneck case for GpI, and work in the model of matrix groups over finite fields. Our main results are as follows. •Although search-to-decision and counting-to-decision reductions have been known for over four decades for GraphIsomorphism(GI), they had remained open for GpI, explicitly asked by Arvind & Torán (Bull. EATCS, 2005). Extending methods from TensorIsomorphism(Grochow & Qiao, ITCS 2021), we show moderately exponential-time such reductions withinp-groups of class 2 and exponentp.•Despitethe widely held belief thatp-groups of class 2 and exponentpare the hardest cases of GpI, there was no reduction to these groups from any larger class of groups. Again using methods from Tensor Isomorphism (ibid.), we show the first such reduction, namely from isomorphism testing ofp-groups of “small” class and exponentpto those of class two and exponentp. For the first results, our main innovation is to develop linear-algebraic analogues of classical graph coloring gadgets, a key technique in studying the structural complexity ofGI. Unlike the graph coloring gadgets, which support restricting to various subgroups of the symmetric group, the problems we study require restricting to various subgroups of the general linear group, which entails significantly different and more complicated gadgets. The analysis of one of our gadgets relies on a classical result from group theory regarding random generation of classical groups (Kantor & Lubotzky, Geom. Dedicata, 1990). For the nilpotency class reduction, we combine a runtime analysis of the Lazard correspondence with TensorIsomorphism-completeness results (Grochow & Qiao, ibid.). 

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2. M icro P rof : Code-level Attribution of Unnecessary Data Transfer in Microservice Applications

   https://doi.org/10.1145/3622787  

   Tariq, Syed Salauddin; Menard, Lance; Su, Pengfei; Roy, Probir (September 2023, ACM Transactions on Architecture and Code Optimization)

   The microservice architecture style has gained popularity due to its ability to fault isolation, ease of scaling applications, and developer’s agility. However, writing applications in the microservice design style has its challenges. Due to the loosely coupled nature, services communicate with others through standard communication APIs. This incurs significant overhead in the application due to communication protocol and data transformation. An inefficient service communication at the microservice application logic can further overwhelm the application. We perform a grey literature review showing that unnecessary data transfer is a real challenge in the industry. To the best of our knowledge, no effective tool is currently available to accurately identify the origins of unnecessary microservice communications that lead to significant performance overhead and provide guidance for optimization. To bridge the knowledge gap, we propose MicroProf, a dynamic program analysis tool to detect unnecessary data transfer in Java-based microservice applications. At the implementation level, MicroProfproposes novel techniques such as remote object sampling and hardware debug registers to monitor remote object usage. MicroProfreports the unnecessary data transfer at the application source code level. Furthermore, MicroProfpinpoints the opportunities for communication API optimization. MicroProfis evaluated on four well-known applications involving two real-world applications and two benchmarks, identifying five inefficient remote invocations. Guided by MicroProf, API optimization achieves an 87.5% reduction in the number of fields within REST API responses. The empirical evaluation further reveals that the optimized services experience a speedup of up to 4.59 ×. 

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3. Comparison of Ce( iv )/Th( iv )-alkynyl complexes and observation of a trans -influence ligand series for Ce( iv )

   https://doi.org/10.1039/D5SC03222A  

   Yang, Qiaomu; Yu, Xiaojuan; Lapsheva, Ekaterina; Pandey, Pragati; Smith, Patrick W; Gupta, Himanshu; Gau, Michael R; Carroll, Patrick J; Minasian, Stefan G; Autschbach, Jochen; et al (August 2025, Chemical Science)

   Organometallic cerium(iv) and thorium(iv) alkynyl complexes were synthesized, and compared experimentally and theoretically. A cerium(iv)trans-influence ligand series was observed and analyzed. 

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4. The Computational Complexity of Feasibility Analysis for Conditional DAG Tasks

   https://doi.org/10.1145/3606342  

   Baruah, Sanjoy; Marchetti-Spaccamela, Alberto (September 2023, ACM Transactions on Parallel Computing)

   The Conditional DAG (CDAG) task model is used for modeling multiprocessor real-time systems containing conditional expressions for which outcomes are not known prior to their evaluation. Feasibility analysis for CDAG tasks upon multiprocessor platforms is shown to be complete for the complexity classpspace; assumingnp≠pspace, this result rules out the use of Integer Linear Programming solvers for solving this problem efficiently. It is further shown that there can be no pseudo-polynomial time algorithm that solves this problem unlessp=pspace. 

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5. Identifying charge-transfer and trip–multiplet states in Co( i ), Co( ii ), and Co( iii ) phthalocyanines using (magneto)optical spectroscopy and (TD)DFT calculations

   https://doi.org/10.1039/d5dt00628g  

   Muldowney, Breanna E; Nevonen, Dustin E; Jeaydi, Towhidi Illius; Ziegler, Christopher J; McNicholas, Brendon J; Nemykin, Victor N (January 2025, Dalton Transactions)

   The electronic structures, charge-transfer, and triplet–multiplet transitions in cobalt(i), cobalt(ii), and cobalt(iii) phthalocyanines were investigated in detail by UV-vis-NIR, MCD, DFT, and TDDFT methods. 

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