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Abstract Utilizing Zwicky Transient Facility (ZTF) data and existing RR Lyrae stars (RRLs) catalogs, this study achieves the first calibration of theP−ϕ₃₁−R₂₁− [Fe/H] andP−ϕ₃₁−A₂−A₁− [Fe/H] relations in the ZTF photometric system for RRab and RRc stars. We also recalibrate the period–absolute magnitude–metallicity (PMZ) and period–Wesenheit–metallicity (PWZ) relations in the ZTFgribands for RRab and RRc stars. Based on nearly 4100 stars with precise measurements ofP,ϕ₃₁,A₂, andA₁, and available spectroscopic metallicity estimates, the photometric metallicity relations exhibit strong internal consistency across different bands, supporting the use of a weighted averaging method for the final estimates. The photometric metallicity estimates of globular clusters based on RR Lyrae members also show excellent agreement with high-resolution spectroscopic measurements, with a typical scatter of 0.15 dex for RRab stars and 0.14 dex for RRc stars, respectively. Using hundreds of local RRLs with newly derived photometric metallicities and precise Gaia Data Release 3 parallaxes, we establish the PMZ and PWZ relations in multiple bands. Validation with globular cluster RR Lyrae members reveals typical distance errors of 3.1% and 3.0% for the PMZ relations, and 3.1% and 2.6% for the PWZ relations for RRab and RRc stars, respectively. Compared to PMZ relations, the PWZ relations are tighter and almost unbiased, making them the recommended choice for distance calculations. We present a catalog of 73,795 RRLs with precise photometric metallicities; over 95% of them have accurate distance measurements. Compared to Gaia DR3, approximately 25,000 RRLs have precise photometric metallicities and distances derived for the first time. 

Abstract: The Pittsburgh Metropolitan Region in Western Pennsylvania, U.S., like many cities glob-ally, historically has an inequitably distributed urban forest and faced street tree biodiversity challenges. Additionally, Pittsburgh faces several barriers and threats to maintaining and expanding its urban tree cover, including pests, diseases, social acceptance, built environment obstacles, and climate change. To address these concerns, in 2012, Pittsburgh created an Urban Forest Master Plan setting equitable forest cover and biodiversity benchmarks. This paper documents the status of achieving these benchmarks and uses microclimate simulations to assess the capacity of these benchmarks in mitigating future mean radiant temperatures. Results demonstrate that the story of Pittsburgh’s urban forest cover, street tree biodiversity, and age diversity is complex, but inequities are primarily driven by income. However, if Pittsburgh can achieve its forest cover benchmarks, it can reduce its neighbourhoods’ 2050 mean radiant temperature below 2010 temperatures, even under climate change-fuelled extreme heat events. The process and results reported in this paper allow designers and decision-makers to calibrate localized urban forest benchmarks more effectively based on various future scenarios while ensuring the equitable distribution of heat mitigation. 

Abstract We present a pioneering achievement in the high-precision photometric calibration of CMOS-based photometry, by application of the Gaia Blue Photometer or Red Photometer (XP) spectra–based synthetic photometry method to the mini-SiTian array (MST) photometry. Through 79 repeated observations of thef02field on the night, we find good internal consistency in the calibrated MSTG_MST-band magnitudes for relatively bright stars, with a precision of about 4 mmag forG_MST ∼ 13. Results from more than 30 different nights (over 3100 observations) further confirm this internal consistency, indicating that the 4 mmag precision is stable and achievable over timescales of months. An independent external validation using spectroscopic data from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope DR10 and high-precision photometric data using CCDs from Gaia DR3 reveals a zero-point consistency better than 1 mmag. Our results clearly demonstrate that CMOS photometry is on par with CCD photometry for high-precision results, highlighting the significant capabilities of CMOS cameras in astronomical observations, especially for large-scale telescope survey arrays. 

This research article is a collaborative set of reflections and provocations stemming from the National Science Foundation (NSF) funded workshop on STS as a Critical Pedagogy, hosted online during the summer of 2021 by Shannon N. Conley and Emily York at James Madison University. The workshop occurred over four separate sessions, bringing together forty participants (including six undergraduate students who contributed as both facilitators and research assistants). Participants self-organized into panels, leading the workshop collective to engage a host of questions, challenges, methods, and practices related to STS and critical pedagogy. Questions included the following. What characterizes critical STS pedagogies? How are critical STS pedagogies enabled and constrained by our institutional and disciplinary locations? What makes STS pedagogies travel? How might we imagine STS pedagogies otherwise? How do our pedagogies shape our research and engagement in the world? How might we critically interrogate the boundaries between research, teaching, service, and engagement, and what becomes visible when we do so? 

Ceratozamia Brongn. is one of the species-rich genera of Cycadales comprising 38 species that are mainly distributed in Mexico, with a few species reported from neighboring regions. Phylogenetic relationships within the genus need detailed investigation based on extensive datasets and reliable systematic approaches. Therefore, we used 30 of the known 38 species to reconstruct the phylogeny based on transcriptome data of 3954 single-copy nuclear genes (SCGs) via coalescent and concatenated approaches and three comparative datasets (nt/nt12/aa). Based on all these methods, Ceratozamia is divided into six phylogenetic subclades within three major clades. There were a few discrepancies regarding phylogenetic position of some species within these subclades. Using these phylogenetic trees, biogeographic history and morphological diversity of the genus are explored. Ceratozamia originated from ancestors in southern Mexico since the mid-Miocene. There is a distinct distribution pattern of species through the Trans-Mexican Volcanic Belt (TMVB), that act as a barrier for the species dispersal at TMVB and its southern and northern part. Limited dispersal events occurred during the late Miocene, and maximum diversification happened during the Pliocene epoch. Our study provides a new insight into phylogenetic relationships, the origin and dispersal routes, and morphological diversity of the genus Ceratozamia. We also explain how past climatic changes affected the diversification of this Mesoamerica-native genus. 

Abstract Background and Aims Cycads are regarded as an ancient lineage of living seed plants, and hold important clues to understand the early evolutionary trends of seed plants. The molecular phylogeny and spatio-temporal diversification of one of the species-rich genera of cycads, Macrozamia, have not been well reconstructed. Methods We analysed a transcriptome dataset of 4740 single-copy nuclear genes (SCGs) of 39 Macrozamia species and two outgroup taxa. Based on concatenated (maximum parsimony, maximum likelihood) and multispecies coalescent analyses, we first establish a well-resolved phylogenetic tree of Macrozamia. To identify cyto-nuclear incongruence, the plastid protein coding genes (PCGs) from transcriptome data are extracted using the software HybPiper. Furthermore, we explore the biogeographical history of the genus and shed light on the pattern of floristic exchange between three distinct areas of Australia. Six key diagnostic characters are traced on the phylogenetic framework using two comparative methods, and infra-generic classification is investigated. Key Results The tree topologies of concatenated and multi-species coalescent analyses of SCGs are mostly congruent with a few conflicting nodes, while those from plastid PCGs show poorly supported relationships. The genus contains three major clades that correspond to their distinct distributional areas in Australia. The crown group of Macrozamia is estimated to around 11.80 Ma, with a major expansion in the last 5–6 Myr. Six morphological characters show homoplasy, and the traditional phenetic sectional division of the genus is inconsistent with this current phylogeny. Conclusions This first detailed phylogenetic investigation of Macrozamia demonstrates promising prospects of SCGs in resolving phylogenetic relationships within cycads. Our study suggests that Macrozamia, once widely distributed in Australia, underwent major extinctions because of fluctuating climatic conditions such as cooling and mesic biome disappearance in the past. The current close placement of morphologically distinct species in the phylogenetic tree may be related to neotenic events that occurred in the genus.