UC Santa Cruz

Abstract: The ATLAS Google Project was established as part of an ongoing evaluation of the use of commercial clouds by the ATLAS Collaboration, in anticipation of the potential future adoption of such resources by WLCG grid sites to fulfil or complement their computing pledges. Seamless integration of Google cloud resources into the worldwide ATLAS distributed computing infrastructure was achieved at large scale and for an extended period of time, and hence cloud resources are shown to be an effective mechanism to provide additional, flexible computing capacity to ATLAS. For the first time a total cost of ownership analysis has been performed, to identify the dominant cost drivers and explore effective mechanisms for cost control. Network usage significantly impacts the costs of certain ATLAS workflows, underscoring the importance of implementing such mechanisms. Resource bursting has been successfully demonstrated, whilst exposing the true cost of this type of activity. A follow-up to the project is underway to investigate methods for improving the integration of cloud resources in data-intensive distributed computing environments and reducing costs related to network connectivity, which represents the primary expense when extensively utilising cloud resources.

Computerized microscopes improve repeatability, throughput, antisepsis, data analysis and data sharing in the biological laboratory, but these machines are cost-prohibitive in most academic environments. This is a barrier into collecting the large and consistent datasets required for machine learning analyses of microscopy data. We demonstrate hardware modifications and software to bring the features of modern computerized microscopes to decades-old legacy laboratory inverted microscopes. We demonstrate automation of X-Y positioning, focus stacking, image acquisition and image storage.

Diet data are critical for describing predator resource use and partitioning among competitors. However, time series needed to properly assess variability in resource use and partitioning are limited, especially in pelagic (open ocean) ecosystems where predators and prey make broad use of horizontal and vertical habitats. We examined a diet time series spanning two decades (1998-2018) consisting of 2749 stomachs from 10 pelagic predators in the southern California Current Ecosystem (SCCE): albacore tuna (Thunnus alalunga), Pacific bluefin tuna (Thunnus orientalis), swordfish (Xiphias gladius), blue shark (Prionace glauca), shortfin mako (Isurus oxyrinchus), common thresher shark (Alopias vulpinus), bigeye thresher shark (Alopias superciliosus), short-beaked common dolphin (Delphinus delphis), long-beaked common dolphin (Delphinus capensis) and northern right whale dolphin (Lissodelphis borealis). We quantified feeding habits with respect to prey taxonomy, length, vertical habitat and horizontal habitat. From 1998 to 2015, each predator exhibited diet variability but maintained consistent resource partitioning with the other predators. Across years, the diets of predators feeding mostly on shallow-living prey (<200 m) were more variable than those feeding on deeper-dwelling prey (>200 m). Following an increase in the abundance of northern anchovy (Engraulis mordax) in the SCCE starting in 2015, the ecological niches of Pacific bluefin tuna and swordfish converged. During 2016-2018, both predators fed more heavily on northern anchovy and other prey that occupy shallow nearshore habitats. We show that pelagic predators can maintain resource partitioning under a wide range of conditions. However, we also observe that drastic changes in resource availability can alter the degree of niche partitioning among competitors, providing new perspectives on the flexibility of predator niches. As climate change continues to alter food webs, understanding how predators forage will be essential for anticipating changes to pelagic ecosystem structure and services.

The author witnessed the Chilean coup d'etat in 1973. Years later he finds José Emilio Pacheco's, the Mexican bard, report on the event.

Despite substantial reductions in the cost of sequencing over the last decade, genetic panels remain relevant due to their cost-effectiveness and flexibility across a variety of sample types. In particular, single nucleotide polymorphism (SNP) panels are increasingly favoured for conservation applications. SNP panels are often used because of their adaptability, effectiveness with low-quality samples, and cost-efficiency for population monitoring and forensics. However, the selection of diagnostic SNPs for population assignment and individual identification can be challenging. The consequences of poor SNP selection are under-powered panels, inaccurate results, and monetary loss. Here, we develop a novel and user-friendly SNP selection pipeline (mPCRselect) that can be used to select SNPs for population assignment and/or individual identification. mPCRselect allows any researcher, who has sufficient SNP-level data, to design a successful and cost-effective SNP panel for a diploid species of conservation concern.

After discovering beauty in the “folk crafts” (mingei) of Korea, Yanagi Sōetsu (1889–1961), an art critic, philosopher, and founder of the Mingei Movement, established the Japan Folk Crafts Museum (Nihon Mingeikan) in 1936. The Mingeikan, with its roots in Japan’s colonization of Korea, plays an uneven role in mediating the postmemory (the memory of those with no direct experience of WWII) of the current generation because the museum does not provide explicit reference to its colonial roots in its exhibitions. Yanagi’s original sentiments in comparison to the museum’s current iteration make for an important case study in understanding how decolonization can occur in Japan. For these reasons it is important to analyze the stakes of unraveling the entangled memories between Japan and Korea within the Mingeikan. While decolonization is an important lens through which to understand contemporary Japan-Korea relations, the specific practices of “decolonization” need to be adapted, revised, and reconsidered when it comes to the legacy of Japan’s imperialism in Korea. This paper takes the Mingeikan as a unique case study to understand how postwar museums in Japan present the history of Japanese colonization in Korea because it does not position itself as a war or peace museum. In order to unravel the historical grief caused by colonialization amidst calls of redress and repatriation, what role do Japanese museums play in erasing or acknowledging Japanese colonial legacies? What current issues make decolonization difficult in Japan? And finally, how does seeing the legacy of Japanese colonialism taking shape in the Mingeikan change our understanding of decolonizing practices?

The shifting climatic regime of maritime Antarctica is driving complex changes across trophic levels that are manifesting differentially across its resident species and regions. Land-breeding pinnipeds have increased their seasonal attendance near Palmer Station since the earliest observations in the mid-1900s, and Antarctic fur seals (Arctocephalus gazella) now represent a significant but unstudied predator population in the region during the austral summer. To characterize the timing of abundance and the fine-scale distribution of this seasonal attendance, we carried out regular drone surveys of terrestrial habitats near Palmer Station in the austral summer of 2020. Using repeat animal counts and photogrammetric data products, we modeled fur seal abundance at survey sites over the period of observation, modeled habitat suitability based on fine-scale topographic habitat characteristics, and estimated abundance across terrestrial habitats near Palmer Station as a function of these products. High habitat suitability was most associated with low-slope and low-elevation inshore terrain and with relatively dry, sun-exposed, and wind-sheltered locations, and estimated peak abundance occurred on March 11 (day 71) of 2020. Models estimated 2289-5544 (95% confidence interval) fur seals on land across all potential terrestrial habitats (41 discrete sites) near Palmer Station and Wylie Bay on the south coast of Anvers Island during peak abundance. This constitutes a first estimate of the aggregate timing, abundance, and distribution of Antarctic fur seals in the terrestrial habitats of this region-a critical first step in understanding the phenology and ecological role of this largely nonbreeding predator population. These findings additionally establish a baseline from which to estimate future changes in this seasonal population and its effects on sympatric terrestrial and marine biota, as the physical environment and food chain of the western Antarctic Peninsula transform under long-term climatic changes.