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The Influence of Fire on a Rare Serpentine Plant Assemblage: A Five Year Study of Darlingtonia Fens
Premise of the study: Serpentine soils have attracted the attention of evolutionary biologists for decades due to their high number of rare and endemic taxa, though less is known about the ecological factors that govern the diversity and composition of serpentine communities. Theory suggests that vegetation on these low-productivity soils will be relatively resilient to fire, the most common natural disturbance in serpentine systems. Methods: We studied the recovery of vegetation in Darlingtonia fens, a unique habitat dominated by herbaceous perennials, from a major fire that burned ~202,000 hectares in California and Oregon’s Klamath Mountains in 2002. We established permanent plots in 8 unburned and 8 burned fens in 2003 and recorded percent cover of vascular plant species. We re-sampled plots each year through 2007. Key results: Burned fens had less plant cover than unburned fens for two years after the fire. Average species density was ~10% lower in burned fens one year after the fire but ~4-8% higher for the next four years. Burned fens exhibited greater evenness, but not until four years after the fire. Differences in community composition were detected between the two fen types, but species ranks were similar, and species neither were added to, nor removed from, the burned assemblages. Conclusions: Burning of Darlingtonia fens has detectable, albeit modest effects on serpentine communities. Because fens have little or no canopy cover, fire has little influence on light availability in this system. This relatively small resource change, combined with high soil moisture and well-developed underground organs of fen plants, produces a highly resilient assemblage.Organismic and Evolutionary BiologyOther Research Uni
Enfoques de sistemas socioecológicos, esenciales para comprender y responder a los impactos complejos de COVID-19 en las personas y el medio ambiente
La pandemia de la enfermedad del coronavirus 2019 (COVID-19) está impactando dramáticamente los sistemas sociales planetarios y humanos que están inseparablemente vinculados. Las enfermedades zoonóticas como la COVID-19 exponen cómo el bienestar humano está inextricablemente interconectado con el medio ambiente y con otras crisis socioecológicas convergentes (impulsadas por los humanos), como las pérdidas dramáticas de biodiversidad, el cambio en el uso de la tierra y el cambio climático. Argumentamos que el COVID-19 es en sí mismo una crisis socioecológica, pero hasta ahora las respuestas no han incluido la resiliencia ecológica, en parte porque la metáfora de la “Antropausa” ha creado una sensación poco realista de comodidad que excusa la inacción. Las narrativas de la antropausa desmienten el hecho de que la extracción de recursos ha continuado durante la pandemia y que los negocios como de costumbre continúan causando una degradación generalizada del ecosistema que requiere atención política inmediata. En algunos casos, las medidas de política de COVID-19 contribuyeron aún más al problema, como la reducción de los impuestos ambientales o la aplicación de las normas. Mientras que algunos sistemas socioecológicos (SSE) están experimentando impactos reducidos, otros están experimentando lo que llamamos un "Antrochoque", con más visitantes y un uso intensificado. Las diversas causas e impactos de la pandemia se pueden comprender mejor con una lente socioecológica. Los conocimientos socioecológicos son necesarios para planificar y desarrollar la resiliencia necesaria para enfrentar la pandemia y futuras crisis socioecológicas. Si nosotros, como sociedad, nos tomamos en serio la reconstrucción mejor de la pandemia, debemos adoptar un conjunto de respuestas de investigación y políticas informadas por el pensamiento SSE
Broadband UBVRI Photometry of Horizontal-Branch and Metal-Poor Candidates from the HK and Hamburg/ESO Surveys. I
We report broadband UBV and/or BVRI CCD photometry for a total of 1857 stars
in the thick-disk and halo populations of the Galaxy. The majority of our
targets were selected as candidate field horizontal-branch or other A-type
stars (FHB/A, N = 576), or candidate low-metallicity stars (N = 1221), from the
HK and Hamburg/ESO objective-prism surveys. Similar data for a small number of
additional stars from other samples are also reported.
These data are being used for several purposes. In the case of the FHB/A
candidates they are used to accurately separate the lower-gravity FHB stars
from various higher-gravity A-type stars, a subsample that includes the
so-called Blue Metal Poor stars, halo and thick-disk blue stragglers,
main-sequence A-type dwarfs, and Am and Ap stars. These data are also being
used to derive photometric distance estimates to high-velocity hydrogen clouds
in the Galaxy and for improved measurements of the mass of the Galaxy.
Photometric data for the metal-poor candidates are being used to refine
estimates of stellar metallicity for objects with available medium-resolution
spectroscopy, to obtain distance estimates for kinematic analyses, and to
establish initial estimates of effective temperature for analysis of
high-resolution spectroscopy of the stars for which this information now
exists.Comment: 22 pages, including 3 figures, 5 tables, and two ascii files of full
data, accepted for publication in the Astrophysical Journal (Supplements
Lactate Regulates Metabolic and Proinflammatory Circuits in Control of T Cell Migration and Effector Functions
Licensed by the Creative Commons Attribution Licens
A perspective on physiological studies supporting the provision of scientific advice for the management of Fraser River sockeye salmon (Oncorhynchus nerka)
The inability of physiologists to effect change in fisheries management has been the source of frustration for many decades. Close collaboration between fisheries managers and researchers has afforded our interdisciplinary team an unusual opportunity to evaluate the emerging impact that physiology can have in providing relevant and credible scientific advice to assist in management decisions. We categorize the quality of scientific advice given to management into five levels based on the type of scientific activity and resulting advice (notions, observations, descriptions, predictions and prescriptions). We argue that, ideally, both managers and researchers have concomitant but separate responsibilities for increasing the level of scientific advice provided. The responsibility of managers involves clear communication of management objectives to researchers, including exact descriptions of knowledge needs and researchable problems. The role of the researcher is to provide scientific advice based on the current state of scientific information and the level of integration with management. The examples of scientific advice discussed herein relate to physiological research on the impact of high discharge and water temperature, pathogens, sex and fisheries interactions on in-river migration success of adult Fraser River sockeye salmon (Oncorhynchus nerka) and the increased understanding and quality of scientific advice that emerges. We submit that success in increasing the quality of scientific advice is a function of political motivation linked to funding, legal clarity in management objectives, collaborative structures in government and academia, personal relationships, access to interdisciplinary experts and scientific peer acceptance. The major challenges with advancing scientific advice include uncertainty in results, lack of integration with management needs and institutional caution in adopting new research. We hope that conservation physiologists can learn from our experiences of providing scientific advice to management to increase the potential for this growing field of research to have a positive influence on resource management
Neuroinflammation, Mast Cells, and Glia: Dangerous Liaisons
The perspective of neuroinflammation as an epiphenomenon following neuron damage is being replaced by the awareness of glia and their importance in neural functions and disorders. Systemic inflammation generates signals that communicate with the brain and leads to changes in metabolism and behavior, with microglia assuming a pro-inflammatory phenotype. Identification of potential peripheral-to-central cellular links is thus a critical step in designing effective therapeutics. Mast cells may fulfill such a role. These resident immune cells are found close to and within peripheral nerves and in brain parenchyma/meninges, where they exercise a key role in orchestrating the inflammatory process from initiation through chronic activation. Mast cells and glia engage in crosstalk that contributes to accelerate disease progression; such interactions become exaggerated with aging and increased cell sensitivity to stress. Emerging evidence for oligodendrocytes, independent of myelin and support of axonal integrity, points to their having strong immune functions, innate immune receptor expression, and production/response to chemokines and cytokines that modulate immune responses in the central nervous system while engaging in crosstalk with microglia and astrocytes. In this review, we summarize the findings related to our understanding of the biology and cellular signaling mechanisms of neuroinflammation, with emphasis on mast cell-glia interactions
Effects of High-Volume Versus High-Load Resistance Training on Skeletal Muscle Growth and Molecular Adaptations
We evaluated the effects of higher-load (HL) versus (lower-load) higher-volume (HV) resistance training on skeletal muscle hypertrophy, strength, and muscle-level molecular adaptations. Trained men (n = 15, age: 23 ± 3 years; training experience: 7 ± 3 years) performed unilateral lower-body training for 6 weeks (3× weekly), where single legs were randomly assigned to HV and HL paradigms. Vastus lateralis (VL) biopsies were obtained prior to study initiation (PRE) as well as 3 days (POST) and 10 days following the last training bout (POSTPR). Body composition and strength tests were performed at each testing session, and biochemical assays were performed on muscle tissue after study completion. Two-way within-subject repeated measures ANOVAs were performed on most dependent variables, and tracer data were compared using dependent samples t-tests. A significant interaction existed for VL muscle cross-sectional area (assessed via magnetic resonance imaging; interaction p = 0.046), where HV increased this metric from PRE to POST (+3.2%, p = 0.018) whereas HL training did not (−0.1%, p = 0.475). Additionally, HL increased leg extensor strength more so than HV training (interaction p = 0.032; HV \u3c HL at POST and POSTPR, p \u3c 0.025 for each). Six-week integrated non-myofibrillar protein synthesis (iNon-MyoPS) rates were also higher in the HV versus HL condition, while no difference between conditions existed for iMyoPS rates. No interactions existed for other strength, VL morphology variables, or the relative abundances of major muscle proteins. Compared to HL training, 6 weeks of HV training in previously trained men optimizes VL hypertrophy in lieu of enhanced iNon-MyoPS rates, and this warrants future research
Globular Cluster UVIT legacy Survey (GlobUleS) III. Omega Centauri in Far-Ultraviolet
We present the first comprehensive study of the most massive globular cluster
Omega Centauri in the far-ultraviolet (FUV) extending from the center to ~ 28%
of the tidal radius using the Ultraviolet Imaging Telescope aboard AstroSat. A
comparison of the FUV-optical color-magnitude diagrams with available canonical
models reveals that the horizontal branch (HB) stars bluer than the knee (hHBs)
and the white dwarfs (WDs) are fainter in the FUV by ~ 0.5 mag than model
predictions. They are also fainter than their counterparts in M13, another
massive cluster. We simulated HB with at least five subpopulations, including
three He-rich populations with a substantial He enrichment of Y up to 0.43 dex,
to reproduce the observed FUV distribution. We find the He-rich younger
subpopulations to be radially more segregated than the He-normal older ones,
suggesting an in-situ enrichment from older generations. The Omega Cen hHBs
span the same effective temperature range as their M13 counterparts, but some
have smaller radii and lower luminosities. This may suggest that a fraction of
Omega Cen hHBs are less massive than those of M13, similar to the result
derived from earlier spectroscopic studies of outer extreme HB stars. The WDs
in Omega Cen and M13 have similar luminosity-radius-effective temperature
parameters, and 0.44 - 0.46 M He-core WD model tracks evolving from
progenitors with Y = 0.4 dex are found to fit the majority of these. This study
provides constraints on the formation models of Omega Cen based on the
estimated range in age, [Fe/H] and Y (in particular), for the HB stars.Comment: Accepted for publication in ApJL; 13 pages, 5 figures, 1 tabl
MusMorph, a database of standardized mouse morphology data for morphometric meta-analyses
Complex morphological traits are the product of many genes with transient or lasting developmental effects that interact in anatomical context. Mouse models are a key resource for disentangling such effects, because they offer myriad tools for manipulating the genome in a controlled environment. Unfortunately, phenotypic data are often obtained using laboratory-specific protocols, resulting in self-contained datasets that are difficult to relate to one another for larger scale analyses. To enable meta-analyses of morphological variation, particularly in the craniofacial complex and brain, we created MusMorph, a database of standardized mouse morphology data spanning numerous genotypes and developmental stages, including E10.5, E11.5, E14.5, E15.5, E18.5, and adulthood. To standardize data collection, we implemented an atlas-based phenotyping pipeline that combines techniques from image registration, deep learning, and morphometrics. Alongside stage-specific atlases, we provide aligned micro-computed tomography images, dense anatomical landmarks, and segmentations (if available) for each specimen (N = 10,056). Our workflow is open-source to encourage transparency and reproducible data collection. The MusMorph data and scripts are available on FaceBase (www.facebase.org, https://doi.org/10.25550/3-HXMC) and GitHub (https://github.com/jaydevine/MusMorph)
Mitochondrial reactive oxygen species promote production of proinflammatory cytokines and are elevated in TNFR1-associated periodic syndrome (TRAPS)
ROS generated by mitochondrial respiration are needed for optimal proinflammatory cytokine production in healthy cells, and are elevated in cells from patients with an autoinflammatory disorder
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