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Introduction: Introducing beneficial soil biota such as arbuscular mycorrhizal fungi (AMF) to agricultural systems may improve plant performance and soil fertility. However, whether bioinocula species composition affects plant growth and soil fertility, and whether fertilizer source influences AMF colonization have not been well characterized. The objectives of this research were to: (1) assess if AMF bioinocula of different species compositions improve raspberry (Rubus idaeus L.) performance and characteristics of soil fertility and (2) evaluate the impact of fertilizer source on AMF colonization. Methods: Five bioinocula with different AMF species compositions and three fertilizer sources were applied to tissue culture raspberry transplants in a randomized complete block design with eight replicates. Plants were grown in a greenhouse for 14 weeks and plant growth, tissue nutrient concentrations, soil fertility, and AMF root colonization were measured. Results: Shoot K and Zn concentrations as well as soil pH and K concentration increased in the Commercial Mix 1 treatment (Glomus, Gigaspora, and Paraglomus AMF species) compared to the non-inoculated control. RFI (raspberry field bioinoculum; uncharacterized AMF and other microbiota) increased soil organic matter (SOM), estimated nitrogen release (ENR), and soil copper (Cu) concentration compared to the non-inoculated control. Furthermore, plants receiving the Mix 1 or RFI treatments, which include more AMF species, had greater AMF root colonization than the remaining treatments. Plants receiving organic fertilizer had significantly greater AMF colonization than conventionally fertilized plants. Conclusion: Taken together, our data indicate that coupling organic fertilizers and bioinocula that include diverse AMF species may enhance raspberry growth and soil fertility.
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Canopy soils occur on tree branches throughout the temperate rainforests of the Pacific Northwest Coast and are recognized as a defining characteristic of these ecosystems. Certain tree species extend adventitious roots into these canopy soil environments. Yet, research on adventitious root-associated fungi remains limited. Our study used microscopy to compare fungal colonization intensity between canopy and forest floor roots of old-growth bigleaf maple (Acer macrophyllum) trees. Subsequently, two high-throughput sequencing platforms were used to explore the spatial and seasonal variation of root-associated fungi between the two soil environments over one year. We found that canopy and forest floor roots had similar colonization intensity and were associating with a diversity of arbuscular mycorrhizal fungi and other potential symbionts, many of which were resolved to species level. Soil environment and seasonality affected root-associated fungal community composition, and several fungal species were indicative of the canopy soil environment. In Washington State's (USA) temperate old-growth rainforests, these canopy soil environments host a unique suite of root-associated fungi. The presence of arbuscular mycorrhizae provides further evidence that adventitious roots form fungal associations to exploit canopy soils for resources, and there may be novel relationships forming with other fungi. These soils may be providing a redundancy compartment (i.e., "nutrient reserve"), imparting a resiliency to disturbances for certain old-growth trees.
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Acer , Micorrizas , Árboles/microbiología , Ecosistema , Raíces de Plantas/microbiología , Suelo , Microbiología del Suelo , Hongos/genéticaRESUMEN
Throughout the COVID-19 pandemic, studies have demonstrated increases in boredom and its negative impact on mental health. This cross-sectional study examines state and trait boredom at four different points of the pandemic using an online sample of participants from the United States (n = 783). The results showed significant increases in boredom proneness, state boredom, substance use, loneliness, and distress. Boredom was associated with increases in each of these variables and a greater likelihood of testing positive for COVID-19. Moreover, the increases in distress, loneliness, and substance use became non-significant when controlling for boredom. Boredom proneness remained associated with all adverse outcomes when accounting for state boredom. In contrast, the relationships between state boredom and most adverse outcomes lost significance when controlling for boredom proneness, and state boredom was positively associated with increased hope for the future. Overall, the results suggest that high boredom proneness is an important vulnerability factor for poor psychological health and risky behaviors during the pandemic. However, high levels of recent state boredom, independent of boredom proneness, do not predict similarly negative outcomes. State boredom may indicate the extent to which one remains hopeful that circumstances will improve without resorting to risky, potentially maladaptive coping strategies.
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Family violence (FV) harms communities worldwide so FV prevention strategies and effective responses are urgently needed. This article reports on FV apparent in a study which explored the experiences of people with both ABI and justice system encounters in Victoria, Australia. One hundred interviews and one focus group consulted people with ABI, their families and carers, and various stakeholder groups in the Victorian justice system in Australia. Qualitative content analysis determined dominant themes and sub-themes and the less common themes. Inductive interpretive content analysis identified themes commonly found in previous published research and themes that appeared unique to, or unanticipated in, our data, such as the FV theme upon which this article focuses. Our findings reveal that FV has adversely affected many people with ABI who came into contact with Victoria's justice system. Further, as ABI and FV often co-occur with substance abuse, mental health problems, socio-economic and many other significant disadvantages, for some FV perpetrators with an ABI, their ABI symptoms and characteristic co-morbidities may be a mitigating factor in their offending. The connection between ABI and family violence emerged as a troubling research theme. Indeed, the impact of FV on too many of our participants with an ABI compels us to call for further related research and secondary prevention programs targeted at FV victims, and offenders, living with ABI. An intersectional understanding of family violence and TBI/ABI in social ecological contexts is required to better understand brain injury at both individual and population levels.
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Although precision medicine has had a mixed impact on the clinical management of patients with advanced-stage cancer overall, for NSCLC, and more specifically for lung adenocarcinoma, the advances have been dramatic, largely owing to the genomic complexity and growing number of druggable oncogene drivers. Furthermore, although tumor tissue is historically the "accepted standard" biospecimen for these molecular analyses, there are considerable innate limitations. Thus, liquid biopsy represents a practical alternative source for investigating tumor-derived somatic alterations. Although data are most robust in NSCLC, patients with other cancer types may also benefit from this minimally invasive approach to facilitate selection of targeted therapies. The liquid biopsy approach includes a variety of methodologies for circulating analytes. From a clinical point of view, plasma circulating tumor DNA is the most extensively studied and widely adopted alternative to tissue tumor genotyping in solid tumors, including NSCLC, first entering clinical practice for detection of EGFR mutations in NSCLC. Since the publication of the first International Association for the Study of Lung Cancer (IASLC) liquid biopsy statement in 2018, several additional advances have been made in this field, leading to changes in the therapeutic decision-making algorithm for advanced NSCLC and prompting this 2021 update. In view of the novel and impressive technological advances made in the past few years, the growing clinical application of plasma-based, next-generation sequencing, and the recent Food and Drug and Administration approval in the United States of two different assays for circulating tumor DNA analysis, IASLC revisited the role of liquid biopsy in therapeutic decision-making in a recent workshop in October 2020 and the question of "plasma first" versus "tissue first" approach toward molecular testing for advanced NSCLC. Moreover, evidence-based recommendations from IASLC provide an international perspective on when to order which test and how to interpret the results. Here, we present updates and additional considerations to the previous statement article as a consensus from a multidisciplinary and international team of experts selected by IASLC.
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Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico , Carcinoma de Pulmón de Células no Pequeñas/genética , Consenso , Humanos , Biopsia Líquida , Neoplasias Pulmonares/genética , OncogenesRESUMEN
Plants interact simultaneously with each other and with soil biota, yet the relative importance of competition vs. plant-soil feedback (PSF) on plant performance is poorly understood. Using a meta-analysis of 38 published studies and 150 plant species, we show that effects of interspecific competition (either growing plants with a competitor or singly, or comparing inter- vs. intraspecific competition) and PSF (comparing home vs. away soil, live vs. sterile soil, or control vs. fungicide-treated soil) depended on treatments but were predominantly negative, broadly comparable in magnitude, and additive or synergistic. Stronger competitors experienced more negative PSF than weaker competitors when controlling for density (inter- to intraspecific competition), suggesting that PSF could prevent competitive dominance and promote coexistence. When competition was measured against plants growing singly, the strength of competition overwhelmed PSF, indicating that the relative importance of PSF may depend not only on neighbour identity but also density. We evaluate how competition and PSFs might interact across resource gradients; PSF will likely strengthen competitive interactions in high resource environments and enhance facilitative interactions in low-resource environments. Finally, we provide a framework for filling key knowledge gaps and advancing our understanding of how these biotic interactions influence community structure.
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Plantas , Microbiología del Suelo , Suelo , Biota , RetroalimentaciónRESUMEN
The over-representation of acquired brain injury (ABI) amongst prisoner and juvenile justice populations is a significant issue across jurisdictions. This article reports on the findings of over 100 interviews conducted in Victoria, Australia with people who have an ABI, as well as key stakeholder groups who work in, or with, the justice system. The study identified systemic problems faced by people with ABI along multiple points of the justice system continuum. Improved identification and diagnosis of ABI, well-resourced support for those with the condition, comprehensive training to improve ABI literacy among all stakeholder groups, and a more appropriate and therapeutic approach to people with ABI in the justice system are all recommended.
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Controlled experiments show that arbuscular mycorrhizal fungi (AMF) can increase competitiveness of exotic plants, potentially increasing invasion success. We surveyed AMF abundance and community composition in Centaurea stoebe and Potentilla recta invasions in the western USA to assess whether patterns were consistent with mycorrhizal-mediated invasions. We asked whether (1) AMF abundance and community composition differ between native and exotic forbs, (2) associations between native plants and AMF shift with invading exotic plants, and (3) AMF abundance and/or community composition differ in areas where exotic plants are highly invasive and in areas where they are not. We collected soil and roots from invaded and native forb communities along invasion gradients and in regions with different invasion densities. We used AMF root colonization as a measure of AMF abundance and characterized AMF communities in roots using 454-sequencing of the LSU-rDNA region. All plants were highly colonized (>60%), but exotic forbs tended to be more colonized than natives (P < 0.001). We identified 30 AMF operational taxonomic units (OTUs) across sites, and community composition was best predicted by abiotic factors (soil texture, pH). Two OTUs in the genera Glomus and Rhizophagus dominated in most communities, and their dominance increased with invasion density (r = 0.57, P = 0.010), while overall OTU richness decreased with invasion density (r = -0.61, P = 0.006). Samples along P. recta invasion gradients revealed small and reciprocal shifts in AMF communities with >45% fungal OTUs shared between neighboring native and P. recta plants. Overall, we observed significant, but modest, differences in AMF colonization and communities between co-occurring exotic and native forbs and among exotic forbs across regions that differ in invasion pressure. While experimental manipulations are required to assess functional consequences, the observed patterns are not consistent with those expected from strong mycorrhizal-mediated invasions.
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Biotic interactions can affect the distribution of species across environmental gradients, and as air and soil temperatures increase, plant community response may depend on interactions with symbionts. We measured the effect of elevated soil temperatures on mycorrhizal function and on the response of both plant and fungal symbionts, using fungal inoculum isolated from either high-temperature thermal or nonthermal grassland soils. Our source for thermal soils was Yellowstone National Park, USA, where plants experience rooting zone temperatures of 45 degrees C or more. In the greenhouse, we grew three plant species (Dichanthelium lanuginosum, Agrostis scabra, and Mimulus guttatus) with three arbuscular mycorrhizal fungal (AMF) treatments (no AMF, nonthermal AMF, thermal AMF) and two soil temperatures (ambient, elevated). Biomass of the facultative thermal plants Agrostis scabra and Mimulus guttatus decreased by 50% in elevated-temperature soils, and AMF had no effect on measured plant traits. In contrast, the biomass and total root length of the obligate thermal plant Dichanthelium lanuginosum were greater at elevated soil temperatures, but only when mycorrhizal. Both mycorrhizal colonization levels and length of extraradical hyphae (ERH) increased with soil temperature across all host species. The source of the AMF inoculum, on the other hand, did not affect colonization level, ERH length, host plant biomass, or flowering for all host species in either temperature treatment, suggesting that AMF from thermal soils are not specifically adapted to higher temperatures. In the field we collected soil cores to measure in situ depth distributions of D. lanuginosum roots and ERH, and to determine which AMF species were active in plants growing in thermal soils. Roots were limited to soils with an average temperature < or =30 degrees C, while ERH existed in the hottest soils we sampled, averaging 35 degrees C. Molecular analyses of roots indicated that thermal AMF communities were composed of both generalist and possibly unique fungal species. The increase in host plant allocation to AMF, apparent lack of temperature adaptation by AMF, and differential host response to AMF suggest that AMF could be significant drivers of plant community response to increased soil temperature associated with global change.
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Calor , Mimulus/microbiología , Micorrizas/fisiología , Poaceae/microbiología , Mimulus/fisiología , Raíces de Plantas/microbiología , Poaceae/fisiología , Suelo , Estrés FisiológicoRESUMEN
Field and laboratory column experiments were performed to assess the effect of elevated pH and reduced ionic strength on the mobilization of natural colloids in a ferric oxyhydroxide-coated aquifer sediment. The field experiments were conducted as natural gradient injections of groundwater amended by sodium hydroxide additions. The laboratory experiments were conducted in columns of undisturbed, oriented sediments and disturbed, disoriented sediments. In the field, the breakthrough of released colloids coincided with the pH pulse breakthrough and lagged the bromide tracer breakthrough. The breakthrough behavior suggested that the progress of the elevated pH front controlled the transport of the mobilized colloids. In the laboratory, about twice as much colloid release occurred in the disturbed sediments as in the undisturbed sediments. The field and laboratory experiments both showed that the total mass of colloid release increased with increasing pH until the concurrent increase in ionic strength limited release. A decrease in ionic strength did not mobilize significant amounts of colloids in the field. The amount of colloids released normalized to the mass of the sediments was similar for the field and the undisturbed laboratory experiments.