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1. Excited-state dynamics of deuterated indigo

   https://doi.org/10.1140/epjd/s10053-023-00744-z  

   Cohen, Trevor; Svadlenak, Nathan; Smith, Charles; Vo, Krystal; Lee, Si-Young; Parejo-Vidal, Ana; Kincaid, Joseph_R A; Sobolewski, Andrzej L; Rode, Michal F; de_Vries, Mattanjah S (September 2023, The European Physical Journal D)

   Abstract Indigo, a rich blue dye, is an incredibly photostable molecule that has survived in ancient art for centuries. It is also unique in that it can undergo both an excited-state hydrogen and proton transfer on the picosecond timescale followed by a ground-state back transfer. Previously, we performed gas phase excited-state lifetime studies on indigo to study these processes in a solvent-free environment, combined with excited-state calculations. We found two decay pathways, a fast sub-nanosecond decay and a slow decay on the order of 10 ns. Calculations of the excited-state potential energy surface found that both hydrogen and proton transfer are nearly isoenergetic separated by a 0.1 eV barrier. To further elucidate these dynamics, we now report a study with deuterated indigo, using resonance-enhanced multi-photon ionization and pump-probe spectroscopy with mass spectrometric isotopomer selection. From new calculations of the excited-state potential energy surface, we find sequential double-proton or hydrogen transfer, whereby the trajectory to the second transfer passes a second barrier and then encounters a conical intersection that leads back to the ground state. We find that deuteration only increases the excited-state lifetimes of the fast decay channel, suggesting tunneling through the first barrier, while the slower channel is not affected and may involve a different intermediate state. Graphical abstract 

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2. Estimates of Hepatitis C Seroprevalence and Viremia in State Prison Populations in the United States

   https://doi.org/10.1093/infdis/jiad227  

   Spaulding, Anne C; Kennedy, Shanika S; Osei, Jeffery; Sidibeh, Ebrima; Batina, Isabella V; Chhatwal, Jagpreet; Akiyama, Matthew J; Strick, Lara B (September 2023, The Journal of Infectious Diseases)

   Abstract BackgroundPrior studies demonstrate that eliminating hepatitis C virus (HCV) in the United States (US) heavily depends on treating incarcerated persons. Knowing the scope of the carceral HCV epidemic by state will help guide national elimination efforts. MethodsBetween 2019 and 2023, all state prison systems received surveys requesting data on hepatitis C antibody and viremic prevalence. We supplemented survey information with publicly available HCV data to corroborate responses and fill in data gaps. ResultsWeighting HCV prevalence by state prison population size, we estimate that 15.2% of the US prison population is HCV seropositive and 8.7% is viremic; 54.9% of seropositive persons have detectable RNA. Applying prevalence estimates to the total prison population at year-end 2021, 91 090 persons with HCV infection resided in a state prison. ConclusionsWith updated and more complete HCV data from all 50 states, HCV prevalence in state prisons is nearly 9-fold higher than the US general population. The heterogeneity in HCV prevalence by state prison system may reflect variable exposure before arrest and/or differences in treatment availability during incarceration. Elimination of HCV in the country depends on addressing the carceral epidemic, and one of the first steps is understanding the size of the problem. 

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3. Optimizing Initial State of Detector Sensors in Quantum Sensor Networks

   https://doi.org/10.1145/3655028  

   Zhan, Caitao; Gupta, Himanshu; Hillery, Mark (June 2024, ACM Transactions on Quantum Computing)

   none (Ed.)

   In this article, we consider a network of quantum sensors, where each sensor is a qubit detector that “fires,” i.e., its state changes when an event occurs close by. The change in state due to the firing of a detector is given by a unitary operator, which is the same for all sensors in the network. Such a network of detectors can be used to localize an event, using a protocol to determine the firing sensor, presumably the one closest to the event. The determination of the firing sensor can be posed as aQuantum State Discriminationproblem, which incurs a probability of error depending on the initial state and the measurement operators used. In this article, we address the problem of determining the optimal initial global state of a network of detectors that incur a minimum probability of error in determining the firing sensor. For this problem, we derive necessary and sufficient conditions for the existence of an initial state that allows for perfect discrimination, i.e., zero probability of error. Using insights from this result, we derive a conjectured optimal solution for the initial state, provide a pathway to prove the conjecture, and validate the conjecture empirically using multiple search heuristics that seem to perform near-optimally. 

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4. Under-Funded and Under-Pressure: State Epidemiologists During the COVID-19 Response

   https://doi.org/10.1017/dmp.2025.110  

   Jones, Jeff; Karim, Safura Abdool; Faden, Ruth; Esmonde, Katelyn; Hutler, Brian; Johns, Michaela; Barnhill, Anne (January 2025, Disaster Medicine and Public Health Preparedness)

   Abstract ObjectivesWe conducted interviews with state epidemiologists involved in the state-level COVID-19 response to understand the challenges and opportunities that state epidemiologists and state health departments faced during COVID-19 and consider the implications for future pandemic responses. MethodsAs part of a broader study on policymaking during COVID-19, we analyzed 12 qualitative interviews with state-epidemiologists from 11 US states regarding the challenges and opportunities they experienced during the COVID-19 response. ResultsInterviewees described the unprecedented demands COVID-19 placed on them, including increased workloads as well as political and public scrutiny. Decades of under-funding and constraints posed particular challenges for meeting these demands and compromised state responses. Emergency funding contributed to ameliorating some challenges. However, state health departments were unable to absorb the funds quickly, which created added pressure for employees. The emergency funding also did not resolve longstanding resource deficits. ConclusionsState health departments were not equipped to meet the demands of a comprehensive COVID-19 response, and increased funding failed to address shortfalls. Effective future pandemic responses will require sustained investment and adequate support to manage on-going and surge capacity needs. Increased public interest and skepticism complicated the COVID-19 response, and additional measures are needed to address these factors. 

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5. State Reconciliation Defects in Infrastructure as Code

   https://doi.org/10.1145/3660790  

   Hassan, Md Mahadi; Salvador, John; Santu, Shubhra_Kanti Karmaker; Rahman, Akond (July 2024, Proceedings of the ACM on Software Engineering)

   In infrastructure as code (IaC), state reconciliation is the process of querying and comparing the infrastructure state prior to changing the infrastructure. As state reconciliation is pivotal to manage IaC-based computing infrastructure at scale, defects related to state reconciliation can create large-scale consequences. A categorization of state reconciliation defects, i.e., defects related to state reconciliation, can aid in understanding the nature of state reconciliation defects. We conduct an empirical study with 5,110 state reconciliation defects where we apply qualitative analysis to categorize state reconciliation defects. From the identified defect categories, we derive heuristics to design prompts for a large language model (LLM), which in turn are used for validation of state reconciliation. From our empirical study, we identify 8 categories of state reconciliation defects, amongst which 3 have not been reported for previously-studied software systems. The most frequently occurring defect category is inventory, i.e., the category of defects that occur when managing infrastructure inventory. Using an LLM with heuristics-based paragraph style prompts, we identify 9 previously unknown state reconciliation defects of which 7 have been accepted as valid defects, and 4 have already been fixed. Based on our findings, we conclude the paper by providing a set of recommendations for researchers and practitioners. 

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