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Abstract Wolf 359 (CN Leo, GJ 406, Gaia DR3 3864972938605115520) is a low-mass star in the fifth-closest neighboring system (2.41 pc). Because of its relative youth and proximity, Wolf 359 offers a unique opportunity to study substellar companions around M stars using infrared high-contrast imaging and radial velocity monitoring. We present the results ofMs-band (4.67μm) vector vortex coronagraphic imaging using Keck-NIRC2 and add 12 Keck-HIRES and 68 MAROON-X velocities to the radial velocity baseline. Our analysis incorporates these data alongside literature radial velocities from CARMENES, the High Accuracy Radial velocity Planet Searcher, and Keck-HIRES to rule out the existence of a close (a< 10 au) stellar or brown dwarf companion and the majority of large gas giant companions. Our survey does not refute or confirm the long-period radial velocity candidate, Wolf 359 b (P∼ 2900 days), but rules out the candidate's existence as a large gas giant (>4M_Jup) assuming an age of younger than 1 Gyr. We discuss the performance of our high-contrast imaging survey to aid future observers using Keck-NIRC2 in conjunction with the vortex coronagraph in theMsband and conclude by exploring the direct imaging capabilities with JWST to observe Jupiter- and Neptune-mass planets around Wolf 359. 

Abstract We combine multiple campaigns of K2 photometry with precision radial velocity measurements from Keck-HIRES to measure the masses of three sub-Neptune-sized planets. We confirm the planetary nature of the massive sub-Neptune K2-182 b ( P b = 4.7 days, R b = 2.69 R ⊕ ) and derive refined parameters for K2-199 b and c ( P b = 3.2 days, R b = 1.73 R ⊕ and P c = 7.4 days, R c = 2.85 R ⊕ ). These planets provide valuable data points in the mass–radius plane, especially as TESS continues to reveal an increasingly diverse sample of sub-Neptunes. The moderately bright ( V = 12.0 mag) early K dwarf K2-182 (EPIC 211359660) was observed during K2 campaigns 5 and 18. We find that K2-182 b is potentially one of the densest sub-Neptunes known to date (20 ± 5 M ⊕ and 5.6 ± 1.4 g cm −3 ). The K5V dwarf K2-199 (EPIC 212779596; V = 12.3 mag), observed in K2 campaigns 6 and 17, hosts two recently confirmed planets. We refine the orbital and planetary parameters for K2-199 b and c by modeling both campaigns of K2 photometry and adding 12 Keck-HIRES measurements to the existing radial velocity data set ( N = 33). We find that K2-199 b is likely rocky, at 6.9 ± 1.8 M ⊕ and 7.2 − 2.0 + 2.1 g cm −3 , and that K2-199 c has an intermediate density at 12.4 ± 2.3 M ⊕ and 2.9 − 0.6 + 0.7 g cm −3 . We contextualize these planets on the mass–radius plane, discuss a small but intriguing population of “superdense” sub-Neptunes ( R p < 3 R ⊕ , M p >20 M ⊕ ), and consider our prospects for the planets’ atmospheric characterization. 

The Statewide Coalition Supporting Underrepresented Populations in Precalculus through Organizational Redesign Toward Engineering Diversity (SC:SUPPORTED), a Design and Development Launch Pilot funded under the National Science Foundation INCLUDES program, is a coalition of secondary districts and postsecondary institutions throughout South Carolina that have joined together to address the systemic issue of mathematics preparation and placement for students pursuing or intending to pursue engineering degrees. In Year One of the project, we used individual data for all 21,656 first-year STEM-intending students enrolled in a public two- or four-year postsecondary institution with ABET-accredited engineering programs in the state to identify specific pathways with high rates of placement in or above calculus, pathways with balanced rates of placement in/below calculus, pathways with high rates of placement below calculus, and “missing” pathways: ones that produced disproportionately few engineering-intending students. From the pathways analysis we identified target locations for focus groups to identify factors that do not readily appear in institutional data, such as the impact of guidance counselor recommendations in a student’s selection of their last high school math course taken. Broad themes emerging from the focus groups provided additional insight into potential interventions at multiple points along educational pathways. These themes also contributed to both the development of a survey for statewide administration and a follow-up study to develop profiles of school district decision-making with direct and indirect effects on mathematics preparation and major selection of students from that district. As we conclude Year Two of our launch pilot, in this paper we integrate a subset of results from different aspects of the project to address both quantitative impact and qualitative context of the roles that poverty and guidance play in gaining access to engineering in South Carolina. 

Improving retention rates of engineering students in higher education has been a nationwide goal aimed at expanding and diversifying the engineering workforce. Initial mathematics placement in institutions is a major predictor for attrition, with 52% of students from two-year institutions starting below calculus as opposed to 14.4% of students from four-year institutions starting below calculus. Consequently, national data shows that the attrition rate for engineering students at two-year institutions is 69% while the attrition rate for engineering students at four-year institutions is 37%. As the prevalence of students taking an indirect path towards completing an engineering degree increases, the examination of those students’ pathways towards an engineering degree is necessary. In the SC:SUPPORTED project, we conducted focus groups with students from two-year and four-year institutions across the state of South Carolina. Themes related to academic influence, social influence and family influence emerged from analysis of the focus group data. Within family influences, which are the ways family members affect a student’s persistence in education, choice of major, and choice of institution, there were differences between students attending two-year institutions and those attending four-year institutions. Family members include parents, siblings, other relatives, and also “fictive” family. The goal of this paper is to discuss the factors that influence why students choose engineering and choose to attend a two-year or four-year institution. 

Improving retention rates of engineering students in higher education has been a nationwide goal aimed at expanding and diversifying the engineering workforce. Initial mathematics placement in institutions is a major predictor for attrition, with 52% of students from two-year institutions starting below calculus as opposed to 14.4% of students from four-year institutions starting below calculus. Consequently, national data shows that the attrition rate for engineering students at two-year institutions is 69% while the attrition rate for engineering students at four-year institutions is 37%. As the prevalence of students taking an indirect path towards completing an engineering degree increases, the examination of those students’ pathways towards an engineering degree is necessary. In the SC:SUPPORTED project, we conducted focus groups with students from two-year and four-year institutions across the state of South Carolina. Themes related to academic influence, social influence and family influence emerged from analysis of the focus group data. Within family influences, which are the ways family members affect a student’s persistence in education, choice of major, and choice of institution, there were differences between students attending two-year institutions and those attending four-year institutions. Family members include parents, siblings, other relatives, and also “fictive” family. The goal of this paper is to discuss the factors that influence why students choose engineering and choose to attend a two-year or four-year institution. 

Previous research has shown that initial mathematics course placement in college is a strong predictor of persistence to an engineering degree. This study examines whether greater access to devices used in high school STEM courses is positively related to a student’s college math course placement. Both qualitative and quantitative data were collected and analyzed. In the quantitative analysis, data on freshmen in Engineering and Engineering-related programs from across 20 public institutions within the same state revealed that classrooms with wireless access and the number of devices dedicated for student use in their high schools were not useful predictors of their math course placement in college. This runs counter to intuition and may provide new insight into the effectiveness of technology implementation within high school classrooms. In a qualitative analysis, the type of devices, frequency, and manner in which the devices were implemented in high school math courses were examined. 

Previous research has shown that initial mathematics course placement in college is a strong predictor of persistence to an engineering degree. This study examines whether greater access to devices used in high school STEM courses is positively related to a student’s college math course placement. Both qualitative and quantitative data were collected and analyzed. In the quantitative analysis, data on freshmen in Engineering and Engineering-related programs from across 20 public institutions within the same state revealed that classrooms with wireless access and the number of devices dedicated for student use in their high schools were not useful predictors of their math course placement in college. This runs counter to intuition and may provide new insight into the effectiveness of technology implementation within high school classrooms. In a qualitative analysis, the type of devices, frequency, and manner in which the devices were implemented in high school math courses were examined.