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1. Restricted mean survival time as a function of restriction time

   https://doi.org/10.1111/biom.13414  

   Zhong, Yingchao ; Schaubel, Douglas E. ( December 2020 , Biometrics)

   Restricted mean survival time (RMST) is a clinically interpretable and meaningful survival metric that has gained popularity in recent years. Several methods are available for regression modeling of RMST, most based on pseudo‐observations or what is essentially an inverse‐weighted complete‐case analysis. No existing RMST regression method allows for the covariate effects to be expressed as functions over time. This is a considerable limitation, in light of the many hazard regression methods that do accommodate such effects. To address this void in the literature, we propose RMST methods that permit estimating time‐varying effects. In particular, we propose an inference framework for directly modeling RMST as a continuous function ofL. Large‐sample properties are derived. Simulation studies are performed to evaluate the performance of the methods in finite sample sizes. The proposed framework is applied to kidney transplant data obtained from the Scientific Registry of Transplant Recipients.

    

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2. A Race Against Time: Modeling Time Lags in Watershed Response

   https://doi.org/10.1029/2018WR023815  

   Ilampooranan, Idhayachandhiran ; Van Meter, K. J. ; Basu, Nandita B. ( May 2019 , Water Resources Research)

   Land use change and agricultural intensification have increased food production but at the cost of polluting surface and groundwater. Best management practices implemented to improve water quality have met with limited success. Such lack of success is increasingly attributed to legacy nutrient stores in the subsurface that may act as sources after reduction of external inputs. However, current water‐quality models lack a framework to capture these legacy effects. Here we have modified the SWAT (Soil Water Assessment Tool) model to capture the effects of nitrogen (N) legacies on water quality under multiple land‐management scenarios. Our new SWAT‐LAG model includes (1) a modified carbon‐nitrogen cycling module to capture the dynamics of soil N accumulation, and (2) a groundwater travel time distribution module to capture a range of subsurface travel times. Using a 502‐km²Iowa watershed as a case study, we found that between 1950 and 2016, 25% of the total watershed N surplus (N Deposition + Fertilizer + Manure + N Fixation − Crop N uptake) had accumulated within the root zone, 14% had accumulated in groundwater, while 27% was lost as riverine output, and 34% was denitrified. In future scenarios, a 100% reduction in fertilizer application led to a 79% reduction in stream N load, but the SWAT‐LAG results suggest that it would take 84 years to achieve this reduction, in contrast to the 2 years predicted in the original SWAT model. The framework proposed here constitutes a first step toward modifying a widely used modeling approach to assess the effects of legacy N on the time required to achieve water‐quality goals.

    

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3. One dislocation at a time

   https://doi.org/10.1038/s41563-023-01555-8  

   Bulatov, Vasily ; Cai, Wei ( June 2023 , Nature Materials)

   The direct observation of enhanced dislocation mobility in iron by in situ electron microscopy offers key insights and adds to the ongoing debate on the mechanisms of hydrogen embrittlement. 

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4. Confinement: A real-time visualization

   https://doi.org/10.1103/PhysRevB.85.075102  

   Cai, Zi ; Wu, Congjun ; Schollwöck, U. ( February 2012 , Physical Review B)
5. A Real Time RF Analog Signal Processor for Time Delay Estimation

   https://doi.org/10.1109/WAMICON53991.2022.9786168  

   Zhang, Hanxiang ; Arigong, Bayaner ( April 2022 , 2022 IEEE 22nd Annual Wireless and Microwave Technology Conference (WAMICON))