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Plant hydraulic traits reveal islands as refugia from worsening drought.
Relatively mesic environments within arid regions may be important conservation targets as 'climate change refugia' for species persistence in the face of worsening drought conditions. Semi-arid southern California and the relatively mesic environments of California's Channel Islands provide a model system for examining drought responses of plants in potential climate change refugia. Most methods for detecting refugia are focused on 'exposure' of organisms to certain abiotic conditions, which fail to assess how local adaptation or acclimation of plant traits (i.e. 'sensitivity') contribute to or offset the benefits of reduced exposure. Here, we use a comparative plant hydraulics approach to characterize the vulnerability of plants to drought, providing a framework for identifying the locations and trait patterns that underlie functioning climate change refugia. Seasonal water relations, xylem hydraulic traits and remotely sensed vegetation indices of matched island and mainland field sites were used to compare the response of native plants from contrasting island and mainland sites to hotter droughts in the early 21st century. Island plants experienced more favorable water relations and resilience to recent drought. However, island plants displayed low plasticity/adaptation of hydraulic traits to local conditions, which indicates that relatively conserved traits of island plants underlie greater hydraulic safety and localized buffering from regional drought conditions. Our results provide an explanation for how California's Channel Islands function as a regional climate refugia during past and current climate change and demonstrate a physiology-based approach for detecting potential climate change refugia in other systems
Education in the Digital World: From the Lens of Millennial Learners
Purpose: The objective of this study is to determine Education in the Digital World: from the lens of millennial learners. This also identifies the cybergogical implications of the issue with digital education as seen through the lens of the outlier. Method: This study uses a mixed-methods sequential explanatory design. A quantitative method was employed during the first phase and the instruments of the study were distributed using google forms. The survey received a total of 85 responses and the results were analyzed using descriptive methods. Following up with a qualitative method, during the second phase the outliers were interviewed, and the results were analyzed using thematic analysis. The results of the mixed methods were interpreted in the form of cybergogical implications. Results: The digital education from the lens of millennial learners in terms of the Benefits of E-Learning and Students' Perceptions of E-Learning received an overall mean of 3.68 which was verbally interpreted as "Highly acceptable". The results reveal that millennial learners' perceptions of digital education are influenced by the convenience in time and location, the fruit of collaboration using online interaction, the skills and knowledge they will acquire using digital resources, and the capability of improving themselves for the future. Conclusion: E-learning significantly improves the quality of the learning and teaching process. Millennial learners with different learning styles and speeds were addressed by its usability andportability features. Millennial learners were able to adopt and learned how to use e-learning. Also, since it is self-paced learning,it allows them to study on their own time and schedule since e-learning can be accessed anytime and anywhere. However, the technological resources of the learners should be considered in the implementation of e-learning. Recommendations: The utilization of e-learning as a medium of instruction for millennial learners. Research Implications: The findings can be used by the institution to create guidelines, procedures, and policies for successfully implementing digital education or E-Learning
How school administrators can support early childhood educators from teacher burnout in the time of pandemic
This paper is aimed at helping school administrators support early childhood educators in preventing and/or dealing with teacher burnout. This study included kindergarten teachers from public and private schools in Parañaque City. The researcher used the explanatory sequential mixed methods design, which is a two-phased model of collecting data. For the first phase of data collection, the participants accomplished the Maslach Burnout Inventory-Educators Survey (MBI-ES), in which their mean scores and frequency levels from each burnout scale—emotional exhaustion, depersonalization, and personal accomplishment—were determined. It was found that the 34 kindergarten teachers who took the MBI-ES had an average frequency level of “a few times a week” in emotional exhaustion, almost “never” in depersonalization, and about “once a week” in personal accomplishment. Those with the highest mean scores and had at least one frequency level higher in emotional exhaustion and/or depersonalization and/or those with the lowest mean scores and had at least one frequency level lower in personal accomplishment than the average frequency levels were interviewed. For the second phase of data collection, a case study approach was conducted among the nine interviewees, in which the individual and cross-case findings were analyzed via thematic analysis.
Findings revealed the various factors that caused the burnout experience among the kindergarten teacher participants due to mismatches in different areas of worklife, increased job demands, and insufficient job resources. The participants shared that the beginning of the school year was very challenging with the full implementation of online education in response to the COVID-19 pandemic. This study also discussed how burnout affected the kindergarten teachers in the personal and professional aspects of their lives. There were those who experienced heavy workload and being in a negative work environment; however, it was also found that most of the respondents were provided with support and were able to cope through the interventions provided by their school leaders and administrators via certain programs and practices. The participants also had their own ways of coping from stress or burnout through utilizing various problem-focused and emotion-focused coping techniques.
This study elaborated on how school administrators can essentially influence the teachers’ burnout experience and how they can support early childhood educators working from home, as a consequence of the pandemic, to help them prevent and/or deal with burnout. School administrators can prepare and plan ahead, collaborate with the teachers, develop and strengthen the teachers’ support system, provide teachers opportunities to be psychologically detached from work, and provide interventions that can help strengthen the teachers’ coping skills and address their specific needs, may they be in the technical, instructional, or emotional aspect, to make interventions really effective.
This study can benefit the school administrators and the early childhood educators, who are encouraged to communicate and collaborate with one another in taking care of the teachers’ well-being and providing effective interventions and a positive work environment to make teaching in the early childhood education setting a fulfilling experience, even during the pandemic. It is recommended to conduct teacher burnout studies among early childhood educators from other levels and during the implementation of blended and face-to-face learning to support the teachers in the new normal.
Keywords: teacher burnout, school administration, early childhood educators, interventions, coping techniques, online education, COVID-19 pandemi
Near-Infrared Imaging of Early-Type Galaxies III. The Near-Infrared Fundamental Plane
Near-infrared imaging data on 251 early-type galaxies in clusters and groups
are used to construct the near-infrared Fundamental Plane (FP) r_eff ~
sigma_0^1.53 _eff^-0.79. The slope of the FP therefore departs from
the virial expectation of r_eff ~ sigma_0^2 _eff^-1 at all optical and
near-infrared wavelengths, which could be a result of the variation of M/L
along the elliptical galaxy sequence, or a systematic breakdown of homology
among the family of elliptical galaxies. The slope of the near-infrared FP
excludes metallicity variations as the sole cause of the slope of the FP. Age
effects, dynamical deviations from a homology, or any combination of these
(with or without metallicity), however, are not excluded. The scatter of both
the near-infrared and optical FP are nearly identical and substantially larger
than the observational uncertainties, demonstrating small but significant
intrinsic cosmological scatter for the FP at all wavelengths. The lack of a
correlation of the residuals of the near-infrared FP and the residuals from the
Mg_2-sigma relation indicates that the thickness of these relations cannot be
ascribed only to age or metallicity effects. Due to this metallicity
independence, the small scatter of the near-infrared FP excludes a model in
which age and metallicity effects ``conspire'' to keep the optical FP thin. All
of these results suggest that the possible physical origins of the FP relations
are complicated due to combined effects of variations of stellar populations
and structural parameters among elliptical galaxies.Comment: to appear in The Astronomical Journal; 35 pages, including 13
Postscript figures and 1 table; uses AAS LaTeX style file
Near-Infrared Imaging of Early-Type Galaxies IV. The Physical Origins of the Fundamental Plane Scaling Relations
The physical origins of the Fundamental Plane (FP) scaling relations are
investigated for early-type galaxies observed at optical and near-infrared
wavelengths. The slope for the FP is shown to increase systematically with
wavelength from the U-band through the K-band. A distance-independent
construction of the observables is described which provides an accurate
measurement of the change in the FP slope between any pair of bandpasses. The
variation of the FP slope with wavelength is strong evidence of systematic
variations in stellar content along the elliptical galaxy sequence. The
intercept of the diagnostic relationship between log(D_K/D_V) and log(sigma_0)
shows no significant dependence on environment within the uncertainties of the
Galactic extinction corrections, demonstrating the universality of the stellar
populations contributions at the level of Delta(V-K)=0.03 mag to the zero-point
of the global scaling relations.
Several other constraints on the properties of early-type galaxies --- the
slope of the Mg_2-sigma_0 relation, the effects of stellar populations
gradients, and deviations of early-type galaxies from a dynamically homologous
family --- are included to construct an empirical, self-consistent model which
provides a complete picture of the underlying physical properties which are
varying along the early-type galaxy sequence. This empirical approach
demonstrates that there are significant systematic variations in both age and
metallicity along the elliptical galaxy sequence, and that a small, but
systematic, breaking of dynamical homology (or a similar, wavelength
independent effect) is required. Predictions for the evolution of the slope of
the FP with redshift are described. [abriged]Comment: to appear in The Astronomical Journal; 40 pages, including 10
Postscript figures and 3 tables; uses AAS LaTeX style file
Elliptical Galaxies with Emission Lines from the Sloan Digital Sky Survey
We present the results of 11 elliptical galaxies with strong nebular emission
lines during our study of star formation history along the Hubble sequence.
After removing the dilution from the underlying old stellar populations by use
of stellar population synthesis model, we derive the accurate fluxes of all
emission lines for these objects, which are later classified with emission line
ratios into one Seyfert 2, six LINERs and four HII galaxies. We also identify
one HII galaxy (A1216+04) as a hitherto unknown Wolf-Rayet galaxy from the
presence of the Wolf-Rayet broad bump at 4650 \AA. We propose that the
star-forming activities in elliptical galaxies are triggered by either
galaxy-galaxy interaction or the merging of a small satellite/a massive star
cluster, as already suggested by recent numerical simulations
Wood allocation trade-offs between fiber wall, fiber lumen, and axial parenchyma drive drought resistance in neotropical trees
Functional relationships between wood density and measures of xylem hydraulic safety and efficiency are ambiguous, especially in wet tropical forests. In this meta-analysis, we move beyond wood density per se and identify relationships between xylem allocated to fibers, parenchyma, and vessels and measures of hydraulic safety and efficiency. We analyzed published data of xylem traits, hydraulic properties and measures of drought resistance from neotropical tree species retrieved from 346 sources. We found that xylem volume allocation to fiber walls increases embolism resistance, but at the expense of specific conductivity and sapwood capacitance. Xylem volume investment in fiber lumen increases capacitance, while investment in axial parenchyma is associated with higher specific conductivity. Dominant tree taxa from wet forests prioritize xylem allocation to axial parenchyma at the expense of fiber walls, resulting in a low embolism resistance for a given wood density and a high vulnerability to drought-induced mortality. We conclude that strong trade-offs between xylem allocation to fiber walls, fiber lumen, and axial parenchyma drive drought resistance in neotropical trees. Moreover, the benefits of xylem allocation to axial parenchyma in wet tropical trees might not outweigh the consequential low embolism resistance under more frequent and severe droughts in a changing climate.Peer reviewe
Towards a Precision Cosmology from Starburst Galaxies at z>2
This work investigates the use of a well-known empirical correlation between
the velocity dispersion, metallicity, and luminosity in H beta of nearby HII
galaxies to measure the distances to HII-like starburst galaxies at high
redshifts. This correlation is applied to a sample of 15 starburst galaxies
with redshifts between z=2.17 and z=3.39 to constrain Omega_m, using data
available from the literature. A best-fit value of Omega_m = 0.21 +0.30 -0.12
in a Lambda-dominated universe and of Omega_m = 0.11 +0.37 -0.19 in an open
universe is obtained. A detailed analysis of systematic errors, their causes,
and their effects on the values derived for the distance moduli and Omega_m is
carried out. A discussion of how future work will improve constraints on
Omega_m by reducing the errors is also presented.Comment: 7 pages, 3 figures, accepted for publication in MNRA
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