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1. Nonadiabatic reaction dynamics to silicon monosulfide (SiS): A key molecular building block to sulfur-rich interstellar grains

   https://doi.org/10.1126/sciadv.abg7003  

   Doddipatla, Srinivas; He, Chao; Goettl, Shane J.; Kaiser, Ralf I.; Galvão, Breno R.; Millar, Tom J. (June 2021, Science Advances)

   Sulfur- and silicon-containing molecules are omnipresent in interstellar and circumstellar environments, but their elementary formation mechanisms have been obscure. These routes are of vital significance in starting a chain of chemical reactions ultimately forming (organo) sulfur molecules—among them precursors to sulfur-bearing amino acids and grains. Here, we expose via laboratory experiments, computations, and astrochemical modeling that the silicon-sulfur chemistry can be initiated through the gas-phase reaction of atomic silicon with hydrogen sulfide leading to silicon monosulfide (SiS) via nonadiabatic reaction dynamics. The facile pathway to the simplest silicon and sulfur diatomic provides compelling evidence for the origin of silicon monosulfide in star-forming regions and aids our understanding of the nonadiabatic reaction dynamics, which control the outcome of the gas-phase formation in deep space, thus expanding our view about the life cycle of sulfur in the galaxy. 

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2. Building Asymmetric Lipid Bilayers for Molecular Dynamics Simulations: What Methods Exist and How to Choose One?

   https://doi.org/10.3390/membranes13070629  

   Chaisson, Emily H.; Heberle, Frederick A.; Doktorova, Milka (July 2023, Membranes)

   The compositional asymmetry of biological membranes has attracted significant attention over the last decade. Harboring more differences from symmetric membranes than previously appreciated, asymmetric bilayers have proven quite challenging to study with familiar concepts and techniques, leaving many unanswered questions about the reach of the asymmetry effects. One particular area of active research is the computational investigation of composition- and number-asymmetric lipid bilayers with molecular dynamics (MD) simulations. Offering a high level of detail into the organization and properties of the simulated systems, MD has emerged as an indispensable tool in the study of membrane asymmetry. However, the realization that results depend heavily on the protocol used for constructing the asymmetric bilayer models has sparked an ongoing debate about how to choose the most appropriate approach. Here we discuss the underlying source of the discrepant results and review the existing methods for creating asymmetric bilayers for MD simulations. Considering the available data, we argue that each method is well suited for specific applications and hence there is no single best approach. Instead, the choice of a construction protocol—and consequently, its perceived accuracy—must be based primarily on the scientific question that the simulations are designed to address. 

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3. Identification of Network Dynamics and Disturbance for a Multizone Building

   https://doi.org/10.1109/TCST.2019.2949546  

   Zeng, Tingting; Barooah, Prabir (June 2020, IEEE Transactions on Control Systems Technology)
4. Identification of Network Dynamics and Disturbance for a Multi-zone Building

   Zeng, Tingting; Barooah, Prabir (December 2018, 2nd {IFAC} Conference on Cyber-Physical and Human Systems)

   We propose a method that simultaneously identifies a sparse transfer matrix and disturbance for a multi-zone building’s dynamics from input-output measurements. An l1 -regularized least-squares optimization problem is solved to obtain a sparse solution, so that only dominant interactions among zones are retained in the model. The disturbance is assumed to be piecewise-constant: the assumption aids identification and is motivated by the nature of occupancy that determines the disturbance. Application of our method on data from a simulation model shows promising results. 

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5. Building an end-to-end BAD application

   https://doi.org/10.1145/3465480.3467840  

   Shirazi, Shahrzad Haji; Carey, Michael J.; Tsotras, Vassilis J. (June 2021, Proceedings of the 15th ACM International Conference on Distributed and Event-based Systems)

   null (Ed.)

   Traditional big data infrastructures are passive in nature, passively answering user requests to process and return data. In many applications however, users not only need to analyze data, but also to subscribe to and actively receive data of interest, based on their subscriptions. Their interest may include the incoming data's content as well as its relationships to other data. Moreover, data delivered to subscribers may need to be enriched with additional relevant and actionable information. To address this Big Active Data (BAD) challenge we have advocated the need for building scalable BAD systems that continuously and reliably capture big data while enabling timely and automatic delivery of relevant and possibly enriched information to a large pool of subscribers. In this demo we showcase how to build an end-to-end active application using a BAD system and a standard email broker for data delivery. This includes enabling users to register their interests with the bad system, ingesting and monitoring data, and producing customized results and delivering them to the appropriate subscribers. Through this example we demonstrate that even complex active data applications can be created easily and scale to many users, considerably limiting the effort of application developers, if a BAD approach is taken. 

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