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1. Newton-CG Methods for Nonconvex Unconstrained Optimization with Hölder Continuous Hessian

   https://doi.org/10.1287/moor.2023.0356  

   He, Chuan; Huang, Heng; Lu, Zhaosong (May 2025, Mathematics of Operations Research)

   In this paper, we consider a nonconvex unconstrained optimization problem minimizing a twice differentiable objective function with Hölder continuous Hessian. Specifically, we first propose a Newton-conjugate gradient (Newton-CG) method for finding an approximate first- and second-order stationary point of this problem, assuming the associated Hölder parameters are explicitly known. Then, we develop a parameter-free Newton-CG method without requiring any prior knowledge of these parameters. To the best of our knowledge, this method is the first parameter-free second-order method achieving the best-known iteration and operation complexity for finding an approximate first- and second-order stationary point of this problem. Finally, we present preliminary numerical results to demonstrate the superior practical performance of our parameter-free Newton-CG method over a well-known regularized Newton method. Funding: C. He was partially financially supported by the Wallenberg AI, Autonomous Systems and Software Program funded by the Knut and Alice Wallenberg Foundation. H. Huang was partially financially supported by the National Science Foundation [Award IIS-2347592]. Z. Lu was partially financially supported by the National Science Foundation [Award IIS-2211491], the Office of Naval Research [Award N00014-24-1-2702], and the Air Force Office of Scientific Research [Award FA9550-24-1-0343]. 

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2. Modifying the CREATE method with inclusive approaches helps students engage with socioscientific applications of the primary scientific literature

   https://doi.org/10.1128/jmbe.00078-25  

   Worthington, Delaney; Kelp, Nicole (April 2025, Journal of Microbiology & Biology Education)

   Floyd, Jeanetta H (Ed.)

   ABSTRACT Undergraduate students need the opportunity to engage with primary scientific literature so they can gain a greater understanding of the scientific process and insights into the larger impacts of scientific research in their field. Reading primary scientific literature (PSL) also provides the opportunity for students to consider the application of primary scientific research to help solve socioscientific issues. Helping students consider more inclusive approaches to science communication can facilitate their connections between primary scientific research and collaborative solving of socioscientific issues. The CREATE method by Hoskins et al. is one pre-existing method of reading scientific papers that gives students a structured opportunity to examine papers. The CREATE method gives students the opportunity to practice scientific process skills, reflect on the impact of research, and consider future studies. We have added an additional element to the CREATE method to help students consider other areas of expertise and ways of knowing needed to apply science in the article to solve socioscientific issues, helping them take a more inclusive approach to reading the PSL. We have deemed this activity ‘inclusive-CREATE’ or iCREATE. Here, we present a curricular plan for implementing iCREATE and show evidence of its efficacy. For instance, we show that the iCREATE method increases students’ science and science communication identity and self-efficacy. We also show that iCREATE increases students’ inclusive science communication self-efficacy, intents, and planned behaviors. Overall, adding a more inclusive element to the CREATE method will help students feel more confident, more like a scientist, and more likely to engage in inclusive science communication behaviors. 

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3. Affordable Method for Hematocrit Determination in Murine Models

   https://doi.org/10.1002/cpz1.1018  

   Branfield, Siobhan; Washington, A Valance; Manfredi, Barbara (April 2024, Current Protocols)

   Abstract Hematocrit (Hct) is a powerful tool often used in a clinical setting for the diagnosis of blood conditions such as anemia. It is also used in the research field as a hematological parameter in both human and mouse models. Measuring Hct, however, involves the use of expensive standardized equipment (such as a CritSpin™ Microhematocrit Centrifuge). Here, we describe a novel, simple, and affordable method to determine the Hct in untreated wild‐type (WT) mice and phenylhydrazine (PHZ)‐induced anemic mice with reasonable accuracy, using a benchtop centrifuge commonly available in laboratories. Hct of murine samples processed with a benchtop centrifuge, when compared to the standardized method CritSpin™, showed comparable results. This approach for determining Hct of murine can prove useful to research laboratories that cannot afford specialized equipment for Hct studies. © 2024 Wiley Periodicals LLC. Basic Protocol 1: Affordable Method for Hematocrit Determination in Murine Models Basic Protocol 2: Murine Sample Validation Support Protocol: Phenylhydrazine‐induced anemia in wild‐type (WT) mice 

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4. Body-of-revolution finite-difference time-domain modeling of hybrid-plasmonic ring resonators

   https://doi.org/10.1364/OE.468596  

   Mirzaei-Ghormish, S.; Shahabadi, M.; Smalley, D_E (September 2022, Optics Express)

   Development of a computational technique for the analysis of quasi-normal modes in hybrid-plasmonic resonators is the main goal of this research. Because of the significant computational costs of this analysis, one has to take various symmetries of these resonators into account. In this research, we consider cylindrical symmetry of hybrid-plasmonic ring resonators and implement a body-of-revolution finite-difference time-domain (BOR-FDTD) technique to analyze these resonators. We extend the BOR-FDTD method by proposing two different sets of auxiliary fields to implement multi-term Drude-Lorentz and multi-term Lorentz models in BOR-FDTD. Moreover, we utilize the filter-diagonalization method to accurately compute the complex resonant frequencies of the resonators. This approach improves numerical accuracy and computational time compared to the Fourier transform method used in previous BOR-FDTD methods. Our numerical analysis is verified by a 2D axisymmetric solver in COMSOL Multiphysics. 

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5. In situ biological particle analyzer based on digital inline holography

   https://doi.org/10.1002/bit.28338  

   Sanborn, Delaney; He, Ruichen; Feng, Lei; Hong, Jiarong (February 2023, Biotechnology and Bioengineering)

   Abstract Obtaining in situ measurements of biological microparticles is crucial for both scientific research and numerous industrial applications (e.g., early detection of harmful algal blooms, monitoring yeast during fermentation). However, existing methods are limited to offer timely diagnostics of these particles with sufficient accuracy and information. Here, we introduce a novel method for real‐time, in situ analysis using machine learning (ML)‐assisted digital inline holography (DIH). Our ML model uses a customized YOLOv5 architecture specialized for the detection and classification of small biological particles. We demonstrate the effectiveness of our method in the analysis of 10 plankton species with equivalent high accuracy and significantly reduced processing time compared to previous methods. We also applied our method to differentiate yeast cells under four metabolic states and from two strains. Our results show that the proposed method can accurately detect and differentiate cellular and subcellular features related to metabolic states and strains. This study demonstrates the potential of ML‐driven DIH approach as a sensitive and versatile diagnostic tool for real‐time, in situ analysis of both biotic and abiotic particles. This method can be readily deployed in a distributive manner for scientific research and manufacturing on an industrial scale. 

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