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AbstractRapid Access Ice Drill is a new drilling technology capable of quickly accessing the glacial bed of Antarctic ice sheets, retrieving ice core and rock core samples, and providing boreholes for downhole logging of physical properties. Scientific goals include searching for old ice near the glacial bed and sampling subglacial bedrock. During field trials near McMurdo Station on a piedmont glacier at Minna Bluff in the 2019–20 austral summer, we successfully completed a ‘top-to-bottom’ operational sequence in three boreholes by (1) augering through firn, (2) creating a borehole packer seal in non-porous ice, (3) establishing fluid circulation, (4) quickly drilling a borehole in ice at penetration rates up to 1.2 m min−1, (5) acquiring a short ice core at depth, (6) penetrating the glacial bed at a depth of ~677 m, (7) recovering a 3.2 m core of ice, basal till and subglacial bedrock, (8) optically logging the borehole on wireline, (9) testing hydrofracture potential by overpressuring the borehole fluid and (10) operating in an environmentally benign yet rapid field mode. Minna Bluff testing, therefore, demonstrates the effectiveness of this integrated system to drill rapidly through thick ice and penetrate across the glacial bed to take cores of bedrock.

Epigenetics is an important source of variation in complex traits that is not due to changes in DNA sequences, and is dependent on the environment the individuals are exposed to. Therefore, we aimed to estimate transgenerational epigenetic heritability, percentage of resetting epigenetic marks, genetic parameters, and predicting breeding values using genetic and epigenetic models for growth, body composition, and reproductive traits in Landrace pigs using routinely recorded datasets. Birth and weaning weight, backfat thickness, total number of piglets born, and number of piglets born alive (BW, WW, BF, TNB, and NBA, respectively) were investigated. Models including epigenetic effects had a similar or better fit than solely genetic models. Including genomic information in epigenetic models resulted in large changes in the variance component estimates. Transgenerational epigenetic heritability estimates ranged between 0.042 (NBA) to 0.336 (BF). The reset coefficient estimates for epigenetic marks were between 80% and 90%. Heritability estimates for the direct additive and maternal genetic effects ranged between 0.040 (BW) to 0.502 (BF) and 0.034 (BF) to 0.134 (BW), respectively. Repeatability of the reproductive traits ranged between 0.098 (NBA) to 0.148 (TNB). Prediction accuracies, bias, and dispersion of breeding values ranged between 0.199 (BW) to 0.443 (BF), −0.080 (WW) to 0.034 (NBA), and −0.134 (WW) to 0.131 (TNB), respectively, with no substantial differences between genetic and epigenetic models. Transgenerational epigenetic heritability estimates are moderate for growth and body composition and low for reproductive traits in North American Landrace pigs. Fitting epigenetic effects in genetic models did not impact the prediction of breeding values. [ABSTRACT FROM AUTHOR]

Simple Summary: Detecting circulating tumor DNA (ctDNA) in the blood has emerged as a valuable method for evaluating several different cancers. Most anal cancers are caused by HPV infection, which is typically identified through the examination of tissue specimens. In this study, we describe a novel method for detecting HPV in the ctDNA using next-generation DNA sequencing on blood samples from patients with advanced anal cancer. The assay was able to detect multiple types of HPV, including uncommon variants. Additionally, the assay appeared to correlate with the disease burden and response to treatment. HPV DNA can often integrate into cancer DNA, which was detectable using our assay, and we show that this may prognosticate which patients are more resistant to treatment. Background: To extend the practicality of liquid biopsy beyond the historical HPV circulating tumor DNA (ctDNA) assays, we evaluated the clinical relevance of a novel next-generation sequencing HPV ctDNA assay in patients with locally advanced and metastatic squamous cell cancer of the anal canal (mSCCA). Methods: ctDNA isolated from the plasma of patients with mSCCA was sequenced using a 1.4 Mb hybrid-capture target-enrichment panel covering the whole genome sequences of all 193 HPV types. The HPV type, copy number (CN), and integration sites were determined using a bioinformatic pipeline. Results: A total of 77 plasma samples from 28 patients with HPV-related SCCA were retrospectively analyzed. HPV ctDNA was detected in 26 cases (93%) (including uncommon subtypes). The median HPV CN was higher in metastatic versus locally recurrent/unresectable SCCA (p = 0.043). Changes in the HPV CN were concordant with the radiographic response (p = 0.027). An integration event was detected in 23 patients (82%), with presumed episomal HPV DNA present in the remaining patients. Higher HPV integration (a mean of ≥1 integration across samples) was associated with a worse overall survival from the start of immunotherapy (13.6 months versus 36.0 months; p = 0.003). Conclusions: Using HPV-informed next-generation sequencing of the ctDNA, we found changes in the HPV CN correlated with the treatment response and that HPV integration detected in the ctDNA is an unfavorable prognostic biomarker. [ABSTRACT FROM AUTHOR]

A group involving Métis and Indigenous graduate students from the University of Manitoba and inner-city Indigenous youth developed and participated in an outdoor adventure-based canoe trip in Quetico Provincial Park. The five-day trip was steeped in Métis, Voyageur and Indigenous history and ceremony. This ensuing paper focuses on what is at stake when taking a decolonizing approach toward land-based education involving both Indigenous and non-Indigenous participants that aspires to (re)introduce Indigenous practices, environments and ceremonies. Inspired by recognizing the complexities involved in creating physical activity and sport programming for Indigenous youth under colonial structures within and outside of the academy, we seek to both illuminate and deconstruct the possibilities of measuring the transformative effects that such a trip has on all those involved, including the youth, mentors, and researchers. Drawing on the results of a qualitative study using both Indigenous and Western approaches, we present community-based research focusing on the impacts these experiences have on community building, identity, and decolonization.

The evolution of the flux tube stability parameters in plasma injections at the Saturnian magnetosphere is reviewed. Plasma injections result from an imbalance in the centrifugal, total pressure gradient, and magnetic tension forces acting on plasma in the magnetosphere. Plasma originating from Enceladus tends to move outward due to centrifugal forces while reconnected flux tubes that are depleted of plasma collapse because of the magnetic tension leading to plasma injections. As the flux tube moves inward and contracts, the ambient density and pressure increase sufficiently to resist further collapse and the injected flux tube brakes. During this process the flux tube may also lose its integrity due to particle drifts, which allow exchange of plasma with adjacent flux tubes so as to bring the flux tube closer to equilibrium and stability so that it is indistinguishable from adjacent plasma. Stability parameters using this energy approach are defined and examined. The results show that the net forces push the plasma moves inward for L > 11 and outward for L < 8.5, while equilibrium is generally reached for 8.5 < L < 11, where L is the equatorial magnetic field crossing measured in Saturnian radii. The evolution of the stability parameters can also apply to Jovian and other fast rotating planetary magnetospheres. [ABSTRACT FROM AUTHOR]

Climate change poses a growing threat to the livestock industry, impacting animal productivity, animal welfare, and farm management practices. Thus, enhancing livestock climatic resilience (CR) is becoming a key priority in various breeding programs. CR can be defined as the ability of an animal to be minimally affected or rapidly return to euthermia under thermally stressful conditions. The primary study objectives were to perform genome-wide association studies for 12 CR indicators derived from variability in longitudinal vaginal temperature in lactating sows under heat stress conditions. A total of 31 single nucleotide polymorphisms (SNPs) located on nine chromosomes were considered as significantly associated with nine CR indicators based on different thresholds. Among them, only two SNPs were simultaneously identified for different CR indicators, SSC6:16,449,770 bp and SSC7:39,254,889 bp. These results highlighted the polygenic nature of CR indicators with small effects distributed across different chromosomes. Furthermore, we identified 434 positional genes associated with CR. Key candidate genes include SLC3A2 , STX5 , POLR2G , and GANAB , which were previously related to heat stress responses, protein folding, and cholesterol metabolism. Furthermore, the enriched KEGG pathways and Gene Ontology (GO) terms associated with these candidate genes are linked to stress responses, immune and inflammatory responses, neural system, and DNA damage and repair. The most enriched quantitative trait loci are related to "Meat and Carcass", followed by "Production", "Reproduction", "Health", and "Exterior (conformation and appearance)" traits. Multiple genomic regions were identified associated with different CR indicators, which reveals that CR is a highly polygenic trait with small effect sizes distributed across the genome. Many heat tolerance or HS related genes in our study, such as HSP90AB1 , DMGDH , and HOMER1 , have been identified. The complexity of CR encompasses a range of adaptive responses, from behavioral to cellular. These results highlight the possibility of selecting more heat-tolerant individuals based on the identified SNP for CR indicators. [ABSTRACT FROM AUTHOR]

The San José Bike Party (SJBP) is a diverse collective of cyclists gathering for monthly group rides around the urban centre of San José, California. By leveraging social networking platforms, the SJBP announces a route and theme just prior to the ride each month. We argue that organizing, producing, and participating in these rides constitute a political act which can help to promote civic engagement and collective action. Further, we explored the way in which collective action can be fostered via social media. Through analysis of semi-structured individual interviews, focus-group interviews, moving methodologies and field observations derived from researcher participation in SJBP events, we articulate the complexities of contested and negotiated meanings of the use of technology, social media and activism assigned to the event by participants, yielding these themes: Critical Analysis of Social Media's Influence, Political Expressions in the SJBP and Prefigurative Politics in the SJBP. [ABSTRACT FROM AUTHOR]

Analysis of the ordinary mode (O‐mode) instability is performed to comprehend the nonthermal continuum (NTC) radiation near the plasmapause, taking into account the relativistic wave‐electron resonance effect. The energy source is the anisotropy in the velocity of the minority suprathermal electron population. Numerical solutions demonstrate that the O‐mode can be unstable with multiple narrow frequency bands located close to harmonics of the electron cyclotron frequency above the local electron plasma frequency. These waves have narrow beaming angle bands of nearly 90° $90{}^{\circ}$ relative to the ambient magnetic field. Our findings indicate that NTC radiation generated by this wave‐electron resonance instability near the plasmapause can propagate nearer to the magnetic equator with multiple harmonics, which is in agreement with a recent statistical study using Van Allen Probes. Key Points: The ordinary mode electron anisotropy instability is examined to comprehend the non‐thermal continuum radiation near the plasmapauseResonant ordinary modes are unstable over multiple narrow frequency and wavevector rangesNTC radiation generated by the instability near the plasmapause can propagate nearer to the magnetic equator [ABSTRACT FROM AUTHOR]

To understand the entry of the cool low‐latitude mantle ions into the tail plasma sheet near the flanks under persistent interplanetary magnetic field By, we evaluate the role of the cross‐field diffusive transport by kinetic Alfvén waves (KAWs) by investigating two events observed by multiscale (MMS) spacecraft. Around the separatrix between the open and closed field‐line regions, a two‐component mixing of hot plasma sheet ions of a few keV with cool mantle ions of a few hundred eV was observed, indicating transport across the separatrix. The waves observed between 0.01 and 10 Hz around the separatrix had characteristics consistent with those of KAWs. The consistency allowed us to estimate the wave vectors as a function of frequency by fitting KAW dispersion to the observations. Using the observed wave powers, plasma moments, and the estimated wave vectors, we computed the cross‐field diffusion rates associated with KAWs. The diffusion rates were found to be comparable to or larger than the Bohm diffusion rates during the intervals when the two‐component mixing was observed, indicating that the KAW diffusive transport can play a role in the entry of low‐latitude mantle ions into the plasma sheet. Key Points: We investigate cross‐field diffusive transport for the mixing of cold low‐latitude mantle ions and hot plasma sheet ions observed by MMSThe waves around the separatrix between the low‐latitude mantle and plasma sheet show the characteristics of kinetic Alfvén waves (KAWs)Estimated diffusive transport rates through KAWs are sufficiently large to cause the observed ion mixing [ABSTRACT FROM AUTHOR]

The last glacial period exhibited abrupt Dansgaard-Oeschger climatic oscillations, evidence of which is preserved in a variety of Northern Hemisphere palaeoclimate archives. Ice cores show that Antarctica cooled during the warm phases of the Greenland Dansgaard-Oeschger cycle and vice versa, suggesting an interhemispheric redistribution of heat through a mechanism called the bipolar seesaw. Variations in the Atlantic meridional overturning circulation (AMOC) strength are thought to have been important, but much uncertainty remains regarding the dynamics and trigger of these abrupt events. Key information is contained in the relative phasing of hemispheric climate variations, yet the large, poorly constrained difference between gas age and ice age and the relatively low resolution of methane records from Antarctic ice cores have so far precluded methane-based synchronization at the required sub-centennial precision. Here we use a recently drilled high-accumulation Antarctic ice core to show that, on average, abrupt Greenland warming leads the corresponding Antarctic cooling onset by 218 ± 92 years (2σ) for Dansgaard-Oeschger events, including the Bølling event; Greenland cooling leads the corresponding onset of Antarctic warming by 208 ± 96 years. Our results demonstrate a north-to-south directionality of the abrupt climatic signal, which is propagated to the Southern Hemisphere high latitudes by oceanic rather than atmospheric processes. The similar interpolar phasing of warming and cooling transitions suggests that the transfer time of the climatic signal is independent of the AMOC background state. Our findings confirm a central role for ocean circulation in the bipolar seesaw and provide clear criteria for assessing hypotheses and model simulations of Dansgaard-Oeschger dynamics.