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1. Skyhook: Towards an Arrow-Native Storage System

   https://doi.org/10.1109/CCGrid54584.2022.00017  

   Chakraborty, Jayjeet; Jimenez, Ivo; Rodriguez, Sebastiaan Alvarez; Uta, Alexandru; LeFevre, Jeff; Maltzahn, Carlos (May 2022, The 22nd IEEE/ACM Interna- tional Symposium on Cluster, Cloud and Internet Computing (CCGrid22))

   With the ever-increasing dataset sizes, several file formats such as Parquet, ORC, and Avro have been developed to store data efficiently, save the network, and interconnect bandwidth at the price of additional CPU utilization. However, with the advent of networks supporting 25-100 Gb/s and storage devices delivering 1,000,000 reqs/sec, the CPU has become the bottleneck trying to keep up feeding data in and out of these fast devices. The result is that data access libraries executed on single clients are often CPU-bound and cannot utilize the scale-out benefits of distributed storage systems. One attractive solution to this problem is to offload data-reducing processing and filtering tasks to the storage layer. However, modifying legacy storage systems to support compute offloading is often tedious and requires an extensive understanding of the system internals. Previous approaches re-implemented functionality of data processing frameworks and access libraries for a particular storage system, a duplication of effort that might have to be repeated for different storage systems. This paper introduces a new design paradigm that allows extending programmable object storage systems to embed existing, widely used data processing frameworks and access libraries into the storage layer with no modifications. In this approach, data processing frameworks and access libraries can evolve independently from storage systems while leveraging distributed storage systems’ scale-out and availability properties. We present Skyhook, an example implementation of our design paradigm using Ceph, Apache Arrow, and Parquet. We provide a brief performance evaluation of Skyhook and discuss key results. 

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2. Invasion by an ecosystem engineer changes biotic interactions between native and non‐native taxa

   https://doi.org/10.1002/ece3.9820  

   Holmquist, Anna J.; Adams, Seira A.; Gillespie, Rosemary G. (February 2023, Ecology and Evolution)

   Abstract Earth systems are nearing a global tipping point, beyond which the dynamics of biological communities will become unstable. One major driver of instability is species invasion, especially by organisms that act as “ecosystem engineers” through their modification of abiotic and biotic factors. To understand how native organisms respond to modified habitat, it is essential to examine biological communities within invaded and non‐invaded habitat, identifying compositional shifts in native and non‐native taxa as well as measuring how modification by ecosystem engineers has affected interactions among community members. Using dietary metabarcoding, our study examines the response of a native Hawaiian generalist predator (Araneae:Pagiopalusspp.) to habitat modification by comparing biotic interactions across metapopulations of spiders collected in native forest and sites invaded by kāhili ginger. Our study shows that, although there are shared components of the dietary community, spiders in invaded habitat are eating a less consistent and more diverse diet consisting of more non‐native arthropods which are rarely or entirely undetected in spiders collected from native forest. Additionally, the frequency of novel interactions with parasites was significantly higher in invaded sites, reflected by the frequency and diversity of non‐native Hymenoptera parasites and entomopathogenic fungi. The study highlights the role of habitat modification driven by an invasive plant in altering community structure and biotic interactions, threatening the stability of the ecosystem through significant changes to the biotic community. 

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3. Upland and Riparian Surface Soil Processes in an Urban Creek with Native and Non-Native Vegetation after Fire

   https://doi.org/10.3390/fire5020032  

   Kinoshita, Alicia M.; Becerra, Rey; Miletić, Marta; Mladenov, Natalie (April 2022, Fire)

   Wildfires can pose environmental challenges in urban watersheds by altering the physical and chemical properties of soil. Further, invasive plant species in urban riparian systems may exacerbate changes in geomorphological and soil processes after fires. This research focuses on the 2018 Del Cerro fire, which burned upland and riparian areas surrounding Alvarado Creek, a tributary to the San Diego River in California. The study site has dense and highly flammable non-native vegetation cover (primarily Arundo donax) localized in the stream banks and has primarily native vegetation on the hillslopes. We estimated the post-fire organic matter and particle distributions for six time points during water years 2019 and 2020 at two soil depths, 0–15 cm and 15–30 cm, in upland and riparian areas. We observed some of the largest decreases in organic matter and particle-size distribution after the first post-fire rainfall event and a general return to initial conditions over time. Seasonal soil patterns were related to rainfall and variability in vegetation distribution. The riparian soils had higher variability in organic matter content and particle-size distributions, which was attributed to the presence of Arundo donax. The particle-size distributions were different between upland and riparian soils, where the riparian soils were more poorly graded. Overall, the greatest change occurred in the medium sands, while the fine sands appeared to be impacted the longest, which is a result of decreased vegetation that stabilized the soils. This research provides a better understanding of upland and riparian soil processes in an urban and Mediterranean system that was disturbed by non-native vegetation and fire. 

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4. Second language knowledge can influence native language performance in exclusively native contexts: An approximate replication of Van Hell & Dijkstra (2002)

   https://doi.org/10.1017/s0272263124000457  

   Pelzl, Eric; Jończyk, Rafał; van_Hell, Janet G (December 2024, Studies in Second Language Acquisition)

   Abstract Over the past decades, bilingualism researchers have come to a consensus around a fairly strong view of nonselectivity in bilingual speakers, often citing Van Hell and Dijkstra (2002) as a critical piece of support for this position. Given the study’s continuing relevance to bilingualism and its strong test of the influence of a bilingual’s second language on their first language, we conducted an approximate replication of the lexical decision experiments in the original study (Experiments 2 and 3) using the same tasks and—to the extent possible—the same stimuli. Unlike the original study, our replication was conducted online with Dutch–English bilinguals (rather than in a lab with Dutch–English–French trilinguals). Despite these differences, results overall closely replicated the pattern of cognate facilitation effects observed in the original study. We discuss the replication of outcomes and possible interpretations of subtle differences in outcomes and make recommendations for future extensions of this line of research. 

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5. Native Microbes Amplify Native Seedling Establishment and Diversity While Inhibiting a Non-Native Grass

   https://doi.org/10.3390/plants12051184  

   Koziol, Liz; McKenna, Thomas P.; Bever, James D. (March 2023, Plants)

   Although several studies have shown increased native plant establishment with native microbe soil amendments, few studies have investigated how microbes can alter seedling recruitment and establishment in the presence of a non-native competitor. In this study, the effect of microbial communities on seedling biomass and diversity was assessed by seeding pots with both native prairie seeds and a non-native grass that commonly invades US grassland restorations, Setaria faberi. Soil in the pots was inoculated with whole soil collections from ex-arable land, late successional arbuscular mycorrhizal (AM) fungi isolated from a nearby tallgrass prairie, with both prairie AM fungi and ex-arable whole soil, or with a sterile soil (control). We hypothesized (1) late successional plants would benefit from native AM fungi, (2) that non-native plants would outcompete native plants in ex-arable soils, and (3) early successional plants would be unresponsive to microbes. Overall, native plant abundance, late successional plant abundance, and total diversity were greatest in the native AM fungi+ ex-arable soil treatment. These increases led to decreased abundance of the non-native grass S. faberi. These results highlight the importance of late successional native microbes on native seed establishment and demonstrate that microbes can be harnessed to improve both plant community diversity and resistance to invasion during the nascent stages of restoration. 

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