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In order to explore the effects of high levels of electron correlation on the real-time coupled cluster formalism and algorithmic behavior, we introduce a time-dependent implementation of the CC3 singles, doubles, and approximate triples method. We demonstrate the validity of our derivation and implementation using specific applications of frequency-dependent properties. Terms with triples are calculated and added to the existing CCSD equations, giving the method a nominal O ( N 7 ) scaling. We also use a graphics processing unit accelerated implementation to reduce the computational cost, which we find can speed up the calculation by up to a factor of 13 for test cases of water clusters. In addition, we compare the impact of using single-precision arithmetic compared to conventional double-precision arithmetic. We find no significant difference in polarizabilities and optical-rotation tensor results but a somewhat larger error for first hyperpolarizabilities. Compared to linear response CC3 results, the percentage errors of RT-CC3 polarizabilities and RT-CC3 first hyperpolarizabilities are under 0.1 and 1%, respectively, for a water-molecule test case in a double-ζ basis set. Furthermore, we compare the dynamic polarizabilities obtained using RT-CC3, RT-CCSD, and time-dependent nonorthogonal orbital-optimized coupled cluster doubles (TDNOCCDs) in order to examine the performance of RT-CC3 and the orbital-optimization effect using a set of ten-electron systems.

Background: The burden of Clostridioides difficile as a nosocomial- and community-acquired pathogen has been increasing over the recent decades, including reports of severe outbreaks. Molecular and virulence genotyping are central for the epidemiological surveillance of this pathogen, but need to balance accuracy and rapid turnaround time of the results. While Illumina short-read sequencing has been adopted as the gold standard to investigate C. difficile virulence and transmission routes, little is known about the potential of Nanopore long-read sequencing in this field. The goal of our study was to compare sequencing and assembly quality of 37 C. difficile isolates using Illumina (SPAdes assembled) and Nanopore (Flye and Unicycler assembled) data alone, along with hybrid assemblies obtained with short-read polishing of long reads., Results: Illumina sequencing produced reads with an average quality of 99.68% (Q25), while Nanopore sequencing produced reads reaching an average quality of 96.84% (Q15), showing a tenfold difference in quality. Sequence type (ST) designation from Nanopore assemblies failed to detect ST5, ST7, ST8, ST13 and ST49, while ST designation based on unpolished Nanopore reads using Krocus was successful for all STs. Nanopore sequences exhibited an average of 640 base errors per genome (~ 0.015% substitution rate), which was reflected by the incorrect assignment of over 180 alleles in core genome multilocus sequence typing (cgMLST) analysis. As a result, Nanopore-derived phylogenies were not as accurate as the Illumina reference, and therefore inadequate for precise investigation of transmission events. Both sequencing platforms provided comparable, satisfactory results for the detection of virulence genes tcdA, tcdB, cdtAB and in-frame deletions in tcdC., Conclusion: Compared to Illumina, Nanopore has higher error rate, which limits its application for high-resolution epidemiological surveillance. However, the short analysis time, lower cost and more simple procedure combined with correctly identified STs and virulence genes, makes it an alternative when fast and less detailed analyses are preferred., Competing Interests: Declarations. Ethical approval: No ethical approval was required for this study since the data used was obtained as part of our routine surveillance program. Competing interests: The authors declare no competing interests., (© 2025. The Author(s).)

In a previous publication [S. E. Schrader et al., J. Chem. Phys. 161, 044105 (2024)], it has been shown that Rothe's method can be used to solve the time-dependent Schrödinger equation for the hydrogen atom in a strong laser field using time-dependent Gaussian wave packets. Here, we generalize these results, showing that Rothe's method can propagate arbitrary numbers of thawed, complex-valued, Explicitly Correlated Gaussian (ECGs) functions with dense correlation matrices for systems with varying dimensionality. We consider the multidimensional Hénon-Heiles potential and show that the dynamics can be quantitatively reproduced using only 30 Gaussians in 2D and that accurate spectra can be obtained using 20 Gaussians in 2D and 30-40 Gaussians in 3D and 4D. Therefore, the relevant multidimensional dynamics can be described at high quality using only a small number of ECGs that give a very compact representation of the wave function. This efficient representation, along with the demonstrated ability of Rothe's method to propagate Gaussian wave packets in strong fields and ECGs in complex potentials, paves the way for accurate molecular dynamics calculations beyond the Born-Oppenheimer approximation in strong fields., (© 2025 Author(s). Published under an exclusive license by AIP Publishing.)

Purpose of Review: The advent of checkpoint immunotherapy has dramatically changed the outcomes for patients with cancer. However, a considerable number of patients have little or no response to therapy. We review recent findings on the connection between the gut microbiota and the immune system, exploring whether this link could enhance the effectiveness of immunotherapy., Recent Findings: Clinical studies have reported specific types of bacteria in larger quantities at baseline in responders than in non-responders, especially Akkermansia mucinifila, Ruminococcaceae, Faecalibacterium, and Lachnospiraceae. Following the consumption of a high-fiber diet, bacteria in the gut ferment dietary fiber to short-chain fatty acids (SCFAs), like acetate, propionate, and butyrate. Some of the SCFAs nurture intestinal epithelial cells, and some enter the bloodstream. Here SCFAs can activate DC8 + cytotoxic T-cells to induce cancer cell death. High fiber intake in the diet was associated with a reduced risk of progression or death during checkpoint immunotherapy. Recent findings demonstrate that high-fiber plant-based diets such as the Mediterranean Diet positively influence the gut microbiota whereas antibiotics and proton pump inhibitors can negatively influence outcomes of cancer immunotherapy by changing the gut microbiota. This narrative review provides evidence of an association between types of bacteria and their metabolites and favorable responses to checkpoint immunotherapy. Prospective clinical trials are needed to determine if diet interventions can improve treatment outcomes., Competing Interests: Declarations. Competing Interests: The authors do not have any potential conflicts of interest to disclose. Human and Animal Rights and Informed Conse: As this was a review paper, no human or animal research was conducted by the authors., (© 2024. The Author(s).)