Star Formation Rate Distributions: Inadequacy of the Schechter Function

In this paper we posit that galaxy luminosity functions (LFs) come in two fundamentally different types depending on whether the luminosity traces galaxy stellar mass or its current star formation rate (SFR). Mass function types reflect the older stars and therefore the stellar mass distribution, while SFR function types arise from the young stars and hence the distribution of SFRs. Optical and near-infrared LFs are of the mass function type, and are well fit by a Schechter function (power law with an exponential cutoff at the bright end). In contrast, LFs of the SFR function type are of a different form, one that cannot be adequately described by a Schechter function. We demonstrate this difference by generating SFR distributions for mock samples of galaxies drawn from a Schechter stellar mass distribution along with established empirical relations between the SFR and stellar mass. Compared with the Schechter function, SFR distributions have a shallower decline at the bright end, which can be traced to the large intrinsic scatter of SFRs at any given stellar mass. A superior description of SFR distributions is given by the "Saunders" function, which combines a power law with a Gaussian at the high end. We show that the Schechter-like appearance of UV and H alpha LFs, although they are LFs of SFR function type, results when luminosities are not corrected for dust, or when average statistical corrections are used because individual attenuation measurements are not available. We thus infer that the non-Schechter form of the far-IR LFs is a true reflection of the underlying SFR distribution, rather than the purported artifact of AGN contamination.Comment: Revised after a referee report. Submitted to ApJ. Compatible with B/W printers. Comments are welcom

Dust Attenuation Curves in the Local Universe: Demographics and New Laws for Star-forming Galaxies and High-redshift Analogs

We study dust attenuation curves of 230,000 individual galaxies in the local universe, ranging from quiescent to intensely star-forming systems, using GALEX, SDSS, and WISE photometry calibrated on Herschel-ATLAS. We use a new method of constraining SED fits with infrared luminosity (SED+LIR fitting), and parameterized attenuation curves determined with the CIGALE SED fitting code. Attenuation curve slopes and UV bump strengths are reasonably well constrained independently from one another. We find that $A_{\lambda}/A_V$ attenuation curves exhibit a very wide range of slopes that are on average as steep as the SMC curve slope. The slope is a strong function of optical opacity. Opaque galaxies have shallower curves - in agreement with recent radiate transfer models. The dependence of slopes on the opacity produces an apparent dependence on stellar mass: more massive galaxies having shallower slopes. Attenuation curves exhibit a wide range of UV bump amplitudes, from none to MW-like; with an average strength 1/3 of the MW bump. Notably, local analogs of high-redshift galaxies have an average curve that is somewhat steeper than the SMC curve, with a modest UV bump that can be to first order ignored, as its effect on the near-UV magnitude is 0.1 mag. Neither the slopes nor the strengths of the UV bump depend on gas-phase metallicity. Functional forms for attenuation laws are presented for normal star-forming galaxies, high-z analogs and quiescent galaxies. We release the catalog of associated SFRs and stellar masses (GSWLC-2).Comment: Accepted to ApJ. GSWLC-2 catalog of SED+LIR SFRs and M* to be released Jun 1 at http://pages.iu.edu/~salims/gswlc

Uncomfortable Comfort Women: Examining shame culture and the internal conflict between Japanese-Americans and Korean-Americans regarding the comfort women issue

Women\u27s rights are human rights that should be emphasized across the globe. The sexual slavery system that the Japanese Imperial army put in place during World War II, commonly known as \u27comfort women,\u27 is now getting international attention. 50 years after the war ended, survivors and former \u27comfort women\u27 are now raising their voice and telling their stories. This research paper focuses on the issue of shame culture and how it drives the internal conflict between Japanese-Americans and Korean-Americans today and how this long conflict effects generations today

On the Mass-Metallicity-Star Formation Rate Relation for Galaxies at z∼2z\sim 2

Recent studies have shown that the local mass-metallicity (M-Z) relation depends on the specific star formation rate (SSFR). Whether such a dependence exists at higher redshifts, and whether the resulting M-Z-SFR relation is redshift invariant, is debated. We re-examine these issues by applying the non-parametric techniques of Salim et al. (2014) to ~130 $z\sim2.3$ galaxies with N2 and O3 measurements from KBSS (Steidel et al. 2014). We find that the KBSS M-Z relation depends on SSFR at intermediate masses, where such dependence exists locally. KBSS and SDSS galaxies of the same mass and SSFR ("local analogs") are similarly offset in the BPT diagram relative to the bulk of local star-forming galaxies, and thus we posit that metallicities can be compared self-consistently at different redshifts as long as the masses and SSFRs of the galaxies are similar. We find that the M-Z-SFR relation of $z\sim2$ galaxies is consistent with the local one at $\log M_*<10$, but is offset up to -0.25 dex at higher masses, so it is altogether not redshift invariant. This high-mass offset could arise from a bias that high-redshift spectroscopic surveys have against high-metallicity galaxies, but additional evidence disfavors this possibility. We identify three causes for the reported discrepancy between N2 and O3N2 metallicities at $z\sim2$: (1) a smaller offset that is also present for SDSS galaxies, which we remove with new N2 calibration, (2) a genuine offset due to differing ISM condition, which is also present in local analogs, (3) an additional offset due to unrecognized AGN contamination.Comment: ApJ accepted. 14 pages. Comments welcom

Examining the Relationship Between Preschool Teachers’ Use of Social and Emotional Teaching Strategies and Children’s Challenging Behavior and Social Skills

Because there are immediate and long-term implications when preschool children exhibit challenging behavior in the classroom, it is crucial to prevent and address challenging behavior as early as possible. Social and emotional teaching strategies have been shown to reduce challenging behavior of preschoolers and increase social and emotional skills. The purpose of this quantitative study was to examine if social and emotional teaching strategies correlated with changes in the challenging behavior and social skills of preschoolers with persistent challenging behavior. Data were obtained from an archival data set of a randomized controlled trial (RCT) efficacy study of an intervention for preschoolers with persistent challenging behavior. The data set included baseline measures of teaching practices in classrooms as measured by the Teaching Pyramid Observation Tool (TPOT) and changes in preschooler’s challenging behavior and social skills using the Social Skills Improvement System (SSIS) collected at pre- and post-test of study participation (spanning 4 months). Pearson correlations of the teaching practices and children’s change scores for challenging behavior and social skills were analyzed for possible statistical significance. Results showed that teaching behavior expectations and teaching problem solving were associated with statistically significant reductions in preschoolers’ challenging behavior for children who participated in the intervention group of the original RCT. No statistically significant relationships were identified for teaching social and emotional competencies, friendship skills, or expressing emotions. Implications for persistent challenging behavior in preschool classrooms are discussed

Time-Limited Trials Among Critically Ill Patients With Advanced Medical Illnesses to Reduce Nonbeneficial Intensive Care Unit Treatments: Protocol for a Multicenter Quality Improvement Study.

BackgroundInvasive intensive care unit (ICU) treatments for patients with advanced medical illnesses and poor prognoses may prolong suffering with minimal benefit. Unfortunately, the quality of care planning and communication between clinicians and critically ill patients and their families in these situations are highly variable, frequently leading to overutilization of invasive ICU treatments. Time-limited trials (TLTs) are agreements between the clinicians and the patients and decision makers to use certain medical therapies over defined periods of time and to evaluate whether patients improve or worsen according to predetermined clinical parameters. For patients with advanced medical illnesses receiving aggressive ICU treatments, TLTs can promote effective dialogue, develop consensus in decision making, and set rational boundaries to treatments based on patients' goals of care.ObjectiveThe aim of this study will be to examine whether a multicomponent quality-improvement strategy that uses protocoled TLTs as the default ICU care-planning approach for critically ill patients with advanced medical illnesses will decrease duration and intensity of nonbeneficial ICU care without changing hospital mortality.MethodsThis study will be conducted in medical ICUs of three public teaching hospitals in Los Angeles County. In Aim 1, we will conduct focus groups and semistructured interviews with key stakeholders to identify facilitators and barriers to implementing TLTs among ICU patients with advanced medical illnesses. In Aim 2, we will train clinicians to use protocol-enhanced TLTs as the default communication and care-planning approach in patients with advanced medical illnesses who receive invasive ICU treatments. Eligible patients will be those who the treating ICU physicians consider to be at high risk for nonbeneficial treatments according to guidelines from the Society of Critical Care Medicine. ICU physicians will be trained to use the TLT protocol through a curriculum of didactic lectures, case discussions, and simulations utilizing actors as family members in role-playing scenarios. Family meetings will be scheduled by trained care managers. The improvement strategy will be implemented sequentially in the three participating hospitals, and outcomes will be evaluated using a before-and-after study design. Key process outcomes will include frequency, timing, and content of family meetings. The primary clinical outcome will be ICU length of stay. Secondary outcomes will include hospital length of stay, days receiving life-sustaining treatments (eg, mechanical ventilation, vasopressors, and renal replacement therapy), number of attempts at cardiopulmonary resuscitation, frequency of invasive ICU procedures, and disposition from hospitalization.ResultsThe study began in August 2017. The implementation of interventions and data collection were completed at two of the three hospitals. As of September 2019, the study was at the postintervention stage at the third hospital. We have completed focus groups with physicians at each medical center (N=29) and interviews of family members and surrogate decision makers (N=18). The study is expected to be completed in the first quarter of 2020, and results are expected to be available in mid-2020.ConclusionsThe successful completion of the aims in this proposal may identify a systematic approach to improve communication and shared decision making and to reduce nonbeneficial invasive treatments for ICU patients with advanced medical illnesses.International registered report identifier (irrid)DERR1-10.2196/16301

Measuring mathematical resilience : an application of the construct of resilience to the study of mathematics

To meet the challenge of accelerating demands for quantitative literacy in the work force, improvements are needed in mathematics education. Student skill must be increased at all ability levels while also reducing the achievement gap across gender, racial and ethnic groups to increase their participation in advanced mathematics coursework and representation in mathematics related careers (National Mathematics Advisory Panel, 2008). Research has shown that affective traits such as motivation and attitude are linked to increased likelihood of taking advanced mathematics courses (Ma, 2006) and are significant predictors of improved cognitive activity and achievement (Buff, Reusser, Rakoczy,& Pauli, 2011; Ethington & Wolfe, 1986). In addition, males generally score more favorably than females on affective variables related to mathematics achievement and persistence (McGraw, Lubienski, & Strutchens, 2006; Sherman & Fennema, 1977; Wilkins and Ma, 2003). Although psychological resilience has been researched extensively (Luthar, Cicchetti, & Becker, 2000; Luthar, 2007) the study of mathematical resilience, defined as a positive adaptive stance to mathematics which allows students to continue learning despite adversity, represents a new approach (Johnston-Wilder & Lee, 2010; Rivera & Waxman, 2011). Math anxiety looks at maladaptive response to learning mathematics and is well-studied (Hembree, 1990; Richardson & Suinn, 1977; Tobias, 1978). In contrast, resilience incorporates factors associated with optimal functioning. Although mathematical resilience has been identified as important for success (Johnston-Wilder & Lee, 2010; Rivera & Waxman, 2011), little consensus exists around its definition and no measures of resilience have been rigorously developed and/or validated. Rivera & Waxman (2011) identified the use of teacher nomination of resilient students as a limitation of their study, further motivating development of an instrument. This presentation will report on efforts to develop and validate an instrument measuring mathematical resilience. Ultimately, the measure will aid in developing and testing models that gauge the role of mathematical resilience in student achievement and persistence in advanced coursework. These models can be used to develop interventions to improve mathematical resilience, achievement, and quantitative literacy (Johnston-Wilder & Lee, 2010)