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1. Frenkel biexcitons in hybrid HJ photophysical aggregates

   https://doi.org/10.1126/sciadv.abi5197  

   Gutiérrez-Meza, Elizabeth; Malatesta, Ravyn; Li, Hongmo; Bargigia, Ilaria; Srimath Kandada, Ajay Ram; Valverde-Chávez, David A.; Kim, Seong-Min; Li, Hao; Stingelin, Natalie; Tretiak, Sergei; et al (December 2021, Science Advances)
2. Drought experiment on aquatic vertebrate populations in McRae Creek, HJ Andrews Experimental Forest, 2022

   https://doi.org/10.6073/pasta/75ff37f814062249c02f27173e0efdce  

   Maffia, Madelyn; Swartz, Allison; Warren, Dana Richard; Segura, Catalina (January 2024, Environmental Data Initiative)

   {"Abstract":["Three distinct reaches in McRae Creek west tributary (MCTW) within the HJ Andrews Experimental Forest in western Oregon were designated for manipulation and data collection. Manipulations included increasing the temperature (T), reducing streamflow (Q), and a reference (R reach). Population estimates of vertebrates, specifically Coastal Cutthroat Trout and Coastal Giant Salamander, were obtained using three-pass depletion methods in each reach. A Before-After-Control-Impact (BACI) design was implemented, distinguishing between the "Before" and "After" periods. "Before" surveys were conducted from July 18th to 20th, 2022, while "After" surveys occurred from September 8th to 9th, 2022. During the surveys, each species was identified, noting life stage, and relevant measurements were taken. For trout, these included the length from the snout to the tail fork (Length_Fork_Vent), the snout to the tail (Length_Tail), and weight. In the "Before" survey, all trout were tagged with elastomer tags: red for the T reach, yellow for the Q reach, and orange for the R reach. Trout larger than 80 mm also received PIT tags in their abdominal cavities. Salamanders were measured similarly, not elastomer or PIT tags were applied. During the "After" survey, no new elastomer or PIT tags were inserted; only previously tagged fish were recorded. Additionally, stream cross-sections were surveyed every 5 meters to document stream dimensions. Recorded data included the location, reach, sample date, BACI status, and distance downstream from the upstream cross-section (0 meters). Measurements at each cross-section included wetted width, bankfull width, and depths at five evenly spaced points. Furthermore, pools were identified and measured in each reach, noting the maximum pool depth, depth at the outflow, width, and length. Temperature sensors were installed in each reach, recording stream temperature every 15 minutes. Sensor locations were recorded as the distance downstream from the top of each reach."]} 

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3. Meteorological data from benchmark stations at the HJ Andrews Experimental Forest, 1957 to present

   https://doi.org/10.6073/pasta/5d4ab4b210165d6e860ebe58e0579e4e  

   Daly, Christopher; Schulze, Mark D; McKee, W Arthur (January 2025, Environmental Data Initiative)

   A three-level hydro-climatological network for data monitoring was established in 1994. The networks at each level are nested to form a coordinated program of data acquisition and measurement. A future vision of linking the benchmark meteorological stations with regional weather stations to expand the future scope of studies was also considered in designing this network. The first-level in this top-down approach consists of Benchmark Meteorological Stations (BMS) and Benchmark Stream Stations. The BMS are designed to represent the environment across the Andrews. These stations are intended to provide complete, long-term, high temporal resolution, meso-scale hydroclimatological data. The location of the BMS network is based on factors such as elevation, aspect, vegetation gradients, and accessibility. Collected meteorological parameters are generally standardized across the BMS as well as methods and instrumentation. Secondary Meteorological Stations also follow standardized methods and serve similar purposes but are somewhat limited in meteorological parameters collected. The Primary Meteorological Station (PRIMET), Central Meteorological Station (CENMET), Upper Lookout Meteorological Station (UPLMET), and Vanilla Leaf Meteorological Station (VANMET) are the four Benchmark Stations, Climatic Station at Watershed 2 (CS2MET) and the Hi-15 Meteorological Station (H15MET) are Secondary Stations. Watershed 7 Meteorological Station (WS7MET) was instrumented in 2006 and serves as an additional Secondary Station. In 2024, entities/measurement parameters (precipitation, wind, solar, soil, and snow) from MS001 database were partitioned out into separate databases. 

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4. Concerning the stability of biexcitons in hybrid HJ aggregates of π -conjugated polymers

   https://doi.org/10.1063/5.0090515  

   Bittner, Eric R.; Silva, Carlos (May 2022, The Journal of Chemical Physics)

   Frenkel excitons are the primary photoexcitations in organic semiconductors and are ultimately responsible for the optical properties of such materials. They are also predicted to form bound exciton pairs, termed biexcitons, which are consequential intermediates in a wide range of photophysical processes. Generally, we think of bound states as arising from an attractive interaction. However, here, we report on our recent theoretical analysis, predicting the formation of stable biexciton states in a conjugated polymer material arising from both attractive and repulsive interactions. We show that in J-aggregate systems, 2J-biexcitons can arise from repulsive dipolar interactions with energies E 2 J > 2 E J , while in H-aggregates, 2H-biexciton states with energies E 2 H < 2 E H can arise corresponding to attractive dipole exciton/exciton interactions. These predictions are corroborated by using ultrafast double-quantum coherence spectroscopy on a [poly(2,5-bis(3-hexadecylthiophene-2-yl)thieno[3,2-b]thiophene)] material that exhibits both J- and H-like excitonic behavior. 

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5. Water chemistry in streams and precipitation samples in the HJ Andrews Experimental Forest, 2022-2023

   https://doi.org/10.6073/pasta/c18fc30cecfea57ad18b2624b7a529b3  

   Segura, Catalina; Ortega, Jaimie; Sullivan, Pamela (January 2025, Environmental Data Initiative)

   Water samples have been collected for chemical analysis at various locations in the HJ Andrews Experimental Forest, starting in 2022. The database includes grab samples gathered approximately weekly in selected streams and bulk precipitation collected at the PRIMET meteorological station. Samples were analyzed for cations (Si4+, Ca2+, Mg2+, K+, and Na+) and anions (Cl- and SO42-). 

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