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Remote Sensing of Snowscapes and Caribou (Rangifer tarandus) Movement in the Northwest Territories of Canada
No full textRecent studies probe that snow characteristics may be primary drivers of migration, largely due to caribou\u27s high level of mobility and their dependence on landscape conditions for locomotion. To investigate whether and how snow characteristics such as melt/refreeze status and the presence of ice are related to caribou movement, we used GPS (Global Positioning System) tracking collar data provided by the Government of the Northwest Territories\u27 Department of Environment and Natural Resources to identify individual animal location and migration patterns, with a focus on the Bathurst herd. We analyzed 117 individual female caribou with more than 30,000 observations between 2007 and 2016 from the Bathurst herd in the Northwest Territories of Canada. We used a hierarchical model to estimate the beginning, duration, and end of spring migration and compared these statistics against snowpack characteristics (i.e., the timing of melt onset and melt/refreeze cycles) which we derived from37 GHz vertically polarized (37V GHz) Calibrated, Enhanced-resolution Brightness Temperatures (CETB) at 3.125 km resolution. We found that the start of spring migration is closely associated with the timing of melt onset and is most often preceded by snow melt onset by just a few days. Melt onset and the start of migration proved very closely associated when plotted across all years, suggesting that melt onset events provide either triggers for migration or favorable conditions that increase mobility. A causal relationship between snowmelt timing and caribou migration would allow for anticipation of caribou migratory behavior and potential shifts in herd ranges
Maximum Agreement Linear Prediction via the Concordance Correlation Coefficient
No full textThis paper examines distributional properties and predictive performance of
the estimated maximum agreement linear predictor (MALP) introduced in Bottai,
Kim, Lieberman, Luta, and Pena (2022) paper in The American Statistician, which
is the linear predictor maximizing Lin\u27s concordance correlation coefficient
(CCC) between the predictor and the predictand. It is compared and contrasted,
theoretically and through computer experiments, with the estimated
least-squares linear predictor (LSLP). Finite-sample and asymptotic properties
are obtained, and confidence intervals are also presented. The predictors are
illustrated using two real data sets: an eye data set and a bodyfat data set.
The results indicate that the estimated MALP is a viable alternative to the
estimated LSLP if one desires a predictor whose predicted values possess higher
agreement with the predictand values, as measured by the CCC
Domain Agnostic Fourier Neural Operators
No full textFourier neural operators (FNOs) can learn highly nonlinear mappings between
function spaces, and have recently become a popular tool for learning responses
of complex physical systems. However, to achieve good accuracy and efficiency,
FNOs rely on the Fast Fourier transform (FFT), which is restricted to modeling
problems on rectangular domains. To lift such a restriction and permit FFT on
irregular geometries as well as topology changes, we introduce domain agnostic
Fourier neural operator (DAFNO), a novel neural operator architecture for
learning surrogates with irregular geometries and evolving domains. The key
idea is to incorporate a smoothed characteristic function in the integral layer
architecture of FNOs, and leverage FFT to achieve rapid computations, in such a
way that the geometric information is explicitly encoded in the architecture.
In our empirical evaluation, DAFNO has achieved state-of-the-art accuracy as
compared to baseline neural operator models on two benchmark datasets of
material modeling and airfoil simulation. To further demonstrate the capability
and generalizability of DAFNO in handling complex domains with topology
changes, we consider a brittle material fracture evolution problem. With only
one training crack simulation sample, DAFNO has achieved generalizability to
unseen loading scenarios and substantially different crack patterns from the
trained scenario. Our code and data accompanying this paper are available at
https://github.com/ningliu-iga/DAFNO
Source height and contact with terrestrial soil drive transplanted epiphyte performance
No full textEpiphytes are characterized by their ability to survive without a root connection to the ground, but many basic life‐history traits and ecological trade‐offs of this unique aerial growth habit remain largely uncharacterized. Mortality causes are still not well understood, but falling from the host tree has been suggested as a leading cause of epiphyte mortality and community dynamics. Little empirical evidence exists for why epiphytes do not survive when forced to become terrestrial, and few studies exist that transplant epiphytes between high‐ and low‐forest strata to test trade‐offs between thriving in canopy environments and survival in the forest understorey. Here, we experimentally test two hypotheses regarding the drivers of epiphyte mortality in a cloud forest of central Panama. We test whether simple contact with terrestrial soil is deleterious to epiphytes, preliminarily testing the epiphyte enemy escape hypothesis, and test the vertical niche differentiation hypothesis, wherein epiphytes are specifically adapted for microsites throughout the vertical forest strata. By monitoring survival, leaf loss and health status of 270 transplanted epiphytes for a year and a half, we pinpoint the extent to which soil contact and height of origin regulate epiphyte performance. We found that contact with terrestrial soil itself was detrimental to epiphytes in situ, providing some of the first empirical data to explain why falling onto the ground, versus falling into the understorey, is particularly fatal to epiphytes. However, we also found that mortality rates vary substantially among taxonomic groups and among epiphytes that originally came from different height strata. Synthesis . Plants that are adapted for the canopy experience a trade‐off with higher mortality when in contact with terrestrial soil. Follow‐up studies should explore the role of terrestrial soil microbes and physiological constraints as potential drivers of decreased grounded epiphyte survival. , Resumen Las epífitas son caracterizadas por su habilidad de sobrevivir sin una conexión de raíces hacia la tierra, pero la historia de vida y los equilibrios de esta forma de crecer único aéreo no son bien caracterizados. Las causas de mortalidad todavía no son bien entendidas, pero caerse del árbol huésped ha sido introducido como un manejador subestimado de los dinámicos de comunidades de epífitas vasculares. Poca evidencia empírica existe por porque no sobreviven las epífitas cuando son forzadas estar terrestres, y existen pocos estudios que trasplantan epífitas entre los estratos forestales verticales para probar los equilibrios de sobrevivir en el dosel o en el sotobosque. Aquí, probamos dos hipótesis experimentalmente hacia los manejadores de la mortalidad de epífitas en un bosque nuboso en el centro de la República de Panamá. Probamos si el contacto simple con la tierra del suelo del bosque es perjudicial para las epífitas, en una prueba preliminar de la Hipótesis de Escapa de Enemigos de Epífitas. También probamos la Hipótesis de Diferenciación Vertical de Nichos, donde las epífitas son específicamente adaptadas por los micrositios a lo largo de los estratos forestales verticales. Por monitorear la supervivencia, la pérdida de hojas, y el estado de salud de 270 epífitas trasplantadas por un año y medio, señalamos la medida en la que el lugar en los estratos forestales regula el rendimiento de las epífitas. Encontramos que el contacto con la tierra terrestre sí era perjudicial para las epífitas in situ, que provee algunos de los primeros datos empíricos para explicar por qué caerse en el suelo, en comparación a caerse al sotobosque, es particularmente fatal para las epífitas. Sin embargo, también encontramos que las tasas de mortalidad de epífitas diferenciaron sustantivamente entre los grupos taxonómicos y entre las epífitas que originalmente ocurrieron en estratos forestales verticales diferentes. Síntesis . Las plantas que son adaptadas para vivir en el dosel experimentan una compensación con mortalidad más alto cuando estén en contacto con el suelo terrestre. Estudios siguientes deben explorar el papel de los microbios de la tierra y las limitaciones fisiológicas como impulsores potenciales de una disminución de la supervivencia en las epífitas caídas
Drivers of survival of translocated tortoises
No full textTranslocation of animals, especially for threatened and endangered species, is a currently popular but very challenging activity. We translocated 158 adult Agassiz\u27s desert tortoises ( Gopherus agassizii ), a threatened species, from the National Training Center, Fort Irwin, in the central Mojave Desert in California, USA, to 4 plots as part of a long‐distance, hard‐release, mitigation‐driven translocation to prevent deaths from planned military maneuvers. We monitored demographic and behavioral variables of tortoises fitted with radio‐transmitters from 2008 to 2018. By the end of the project, 17.72% of tortoises were alive, 65.82% were dead, 15.19% were missing, and 1.27% were removed from the study because they returned to Fort Irwin. Mortality was high during the first 3 years: >50% of the released animals died, primarily from predation. Thereafter, mortality declined but remained high. After 10.5 years, survival was highest, 37.50% (15/40), on the plot closest to original home sites, whereas from 2.56% to 23.68% remained alive on the other 3 release plots. Surviving tortoises settled early, repeatedly using locations where they constructed burrows, compared with tortoises that died or disappeared. Models of behavioral and other variables indicated that numbers of repeatedly used locations (burrows) were a driver of survival throughout the study, although plot location, size and sex of tortoises, and distance traveled were contributors, especially during early years. Because >50% mortality occurred, we considered this translocation unsuccessful. The study area appeared to be an ecological sink with historical and current anthropogenic uses contributing to habitat degradation and a decline in both the resident and released tortoises. Our findings will benefit design and selection of future translocation areas
Adapting parent‐focused interventions for diverse caregivers of children with intellectual and developmental disabilities: Lessons learned during global crises
No full textParent‐focused interventions have been designed to provide training and support to caregivers who are essential in achieving positive outcomes for children with intellectual and developmental disabilities (IDD). In 2020, significant crises, including the COVID‐19 pandemic and continued racial tensions, profoundly impacted the livelihood of children with IDD and their families. Many ongoing efforts to address disparities among this population were halted temporarily and required further adaptations. Researchers adapted interventions and support to address the disparities impacting children with IDD and their families with limited guidance. We provide a descriptive case analysis of four parent‐focused interventions that responded to the global crises to continue serving children with IDD and their families. The four distinct programs were based on applied behavior analysis and naturalistic, developmental‐behavioral paradigms that were culturally adapted for families of young children with IDD from diverse cultural and socioeconomic backgrounds. We present the qualitative reports on the challenges and benefits that arose with adapting the four parent‐focused interventions for telehealth implementation. We focused specifically on adaptations made in recruitment and retention, instrumentation and measurement, research staff training, and intervention delivery. We synthesize our experience with challenges and solutions in adapting parent‐focused interventions for racially/ethnically and socioeconomically diverse children with IDD and their families. We conclude with recommendations for researchers and practitioners on methods for adapting parent‐focused interventions to address the significant health disparities that impact racially, ethnically, and socioeconomically diverse children with IDD and their families
What do other people think he deserves? Social influence on utilization of mitigating information regarding a violent offender’s unfortunate life history
No full textThe blameworthiness of an offender is often discussed in groups. Yet, the research literature overwhelmingly examines individuals assessing blameworthiness in isolation. To address this gap in the literature, the present study examines group deliberations about blameworthiness, with a particular focus on how group deliberations impact utilization of mitigating information about an offender’s unfortunate life history. Participants from introductory psychology courses at a U.S. university were placed in groups of two or three and each group also included a confederate who followed a script. Groups were randomly assigned to one of four conditions. In one condition (deed only), groups learned only about the offender’s heinous crimes. In the three remaining conditions, participants also received a historicist narrative regarding how the offender’s unfortunate history deformed his moral character. These conditions differed in terms of the confederate’s arguments: Neutral arguments, arguments to ignore the narrative, or arguments to give great weight to the narrative. Results showed that the historicist narrative was particularly effective at reducing outrage and increasing compassion when the confederate argued for its utilization. The reduction in outrage mediated a reduction in spiteful punitiveness toward the offender. Interestingly, the confederate who urged fellow deliberators to ignore the historicist narrative had no impact on outrage or compassion. We also examined mediation of the impact of historicist narratives on outrage and compassion. We found that when the confederate remained neutral the impact of historicist narratives on outrage and compassion was mediated via diminished perceptions of the offender’s control of self-formation. This mirrors what is typically found in prior work focused on individual judgments. In contrast, when the confederate argued that great weight should be given to the narrative, reductions in outrage were mediated via diminished perceptions of offender freedom of action. This pattern of mediation is not typically found but has been found in one previous study where participants received social encouragement to mitigate blame. Results are discussed in terms of how social influence might alter the inferences draw from historicist narratives. Suggestions for future research on social influence in the context of blame are presented.</jats:p
Combined electric and magnetic field therapy for bone repair and regeneration: an investigation in a 3-mm and an augmented 17-mm tibia osteotomy model in sheep
No full textAbstract
Background
Therapies using electromagnetic field technology show evidence of enhanced bone regeneration at the fracture site, potentially preventing delayed or nonunions.
Methods
Combined electric and magnetic field (CEMF) treatment was evaluated in two standardized sheep tibia osteotomy models: a 3-mm non-critical size gap model and a 17-mm critical size defect model augmented with autologous bone grafts, both stabilized with locking compression plates. CEMF treatment was delivered across the fracture gap twice daily for 90 min, starting 4 days postoperatively (post-OP) until sacrifice (9 or 12 weeks post-OP, respectively). Control groups received no CEMF treatment. Bone healing was evaluated radiographically, morphometrically (micro-CT), biomechanically and histologically.
Results
In the 3-mm gap model, the CEMF group (n‚Äâ=‚Äâ6) exhibited higher callus mineral density compared to the Control group (n‚Äâ=‚Äâ6), two-fold higher biomechanical torsional rigidity and a histologically more advanced callus maturity (no statistically significant differences). In the 17-mm graft model, differences between the Control (n‚Äâ=‚Äâ6) and CEMF group (n‚Äâ=‚Äâ6) were more pronounced. The CEMF group showed a radiologically more advanced callus, a higher callus volume (p‚Äâ=‚Äâ0.003) and a 2.6‚Äâ√ó‚Äâhigher biomechanical torsional rigidity (p‚Äâ=‚Äâ0.024), combined with a histologically more advanced callus maturity and healing.
Conclusions
This study showed that CEMF therapy notably enhanced bone healing resulting in better new bone structure, callus morphology and superior biomechanical properties. This technology could transform a standard inert orthopedic implant into an active device stimulating bone tissue for accelerated healing and regeneration.
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Broadband Electrical Spectroscopy to Distinguish Single-Cell Ca2+ Changes Due to Ionomycin Treatment in a Skeletal Muscle Cell Line
No full textMany skeletal muscle diseases such as muscular dystrophy, myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), and sarcopenia share the dysregulation of calcium (Ca2+) as a key mechanism of disease at a cellular level. Cytosolic concentrations of Ca2+ can signal dysregulation in organelles including the mitochondria, nucleus, and sarcoplasmic reticulum in skeletal muscle. In this work, a treatment is applied to mimic the Ca2+ increase associated with these atrophy-related disease states, and broadband impedance measurements are taken for single cells with and without this treatment using a microfluidic device. The resulting impedance measurements are fitted using a single-shell circuit simulation to show calculated electrical dielectric property contributions based on these Ca2+ changes. From this, similar distributions were seen in the Ca2+ from fluorescence measurements and the distribution of the S-parameter at a single frequency, identifying Ca2+ as the main contributor to the electrical differences being identified. Extracted dielectric parameters also showed different distribution patterns between the untreated and ionomycin-treated groups; however, the overall electrical parameters suggest the impact of Ca2+-induced changes at a wider range of frequencies.</jats:p
