Citrus greening is a bacterial disease with no cure or treatment. Since its onset in Florida, orange production statewide has decreased by more than 90%. A recently approved technology consists of injecting antibiotics into tree trunks, which growers expect to improve tree health and increase yield. We use a spatial equilibrium model to conduct an ex-ante analysis of the not-from-concentrate orange juice market to examine the market and welfare impacts of Florida growers’ adoption of antibiotic trunk injections. Results show yield must increase by at least 83% to generate a positive producer surplus when using a discount rate of 10%.

Over the last decade, the Australian Dark Energy (OzDES) collaboration has used Reverberation Mapping to measure the masses of high redshift supermassive black holes. Here we present the final review and analysis of this OzDES reverberation mapping campaign. These observations use $6-7$ years of photometric and spectroscopic observations of 735 Active Galactic Nuclei (AGN) in the redshift range $z\in [0.13, 3.85]$ and bolometric luminosity range $\log_{10}(L_{\mathrm{bol}})\in [44.3, 47.5] \; \mathrm{erg/s}$. Both photometry and spectra are observed in visible wavelengths, allowing for the physical scale of the AGN broad line region to be estimated from reverberations of the H$\beta$, MgII and CIV emission lines. We successfully use reverberation mapping to constrain the masses of 62 super-massive black holes, and combine with existing data to fit a power law to the lag-luminosity relation for the H$\beta$ and MgII lines with a scatter of $\sim0.25$ dex, the tightest yet identified, fit specifically for consistency with high redshift AGN. We fit a similarly constrained relation for CIV, resolving a tension with the low luminosity literature AGN by accounting for selection effects arising from finite survey length. We also examine the impact of emission line width and luminosity (related to accretion rate) in reducing the scatter of these scaling relationships and find no significant improvement over the lag-only approach for any of the three lines. Using these relations, we further estimate the masses and accretion rates of 246 AGN with single epoch methods. We also use these relations to estimate the relative sizes of the H$\beta$, MgII and CIV emitting regions, and find evidence that the MgII emission may occur further out than H$\beta$. In short, we provide a comprehensive benchmark of high redshift AGN reverberation mapping at the close of this most recent generation of surveys, including light curves, time-delays, and a set of significantly improved radius-luminosity relations for use with high-redshift populations.

Archaeological fieldwork in China commonly relies on short-term labor recruited from nearby villages, forming a long-standing mode of collaboration between state-employed staff and local workers. Drawing on sustained field engagement and interviews at the Chengcun City Site of the Han Dynasty, this research examines how locally recruited workers enter, sustain, and experience participation in archaeological practice. Community members often begin archaeological work during agricultural off-seasons and may accumulate decades of experience. Their trajectories vary: some obtain institutional posts, others return to farming, and many continue in project-based employment. These trajectories indicate that funding structures shape employment continuity and welfare access, while skills developed through long-term practice do not always translate into formal professional status. Archaeological labor constitutes a key mechanism in producing excavation knowledge, shaping professional roles, and structuring heritage governance in everyday practice. Viewed through labor trajectories, archaeological professionalization appears uneven, shaped by institutional arrangements, rural livelihood strategies, and localized opportunities. Based on the Chengcun case, this research points to broader dynamics: large-scale projects rely on localized labor regimes while maintaining differentiated forms of recognition and authority. Reconsidering archaeology through labor offers a perspective on knowledge production, participation, and governance.

Timely soybean planting is important for maximizing yield, with farmers tending to plant their crops earlier. However, when a soybean crop is planted ultra-early (before April 15th in Ohio), seedlings are exposed to cold and moist conditions that can lead to a smaller plant population, delayed canopy closure, and reduced ability to compete with weeds. The objective of this study was to evaluate herbicide treatments for their effect on weed development and soybean yield when the crop was planted ultra-early (before April 15) and at a normal time (early to mid-May in Ohio). Weed biomass was significantly reduced when the crop was treated at early postemergence. However, preemergence followed by early postemergence herbicide applications were generally less effective at suppressing weeds than treatments that included an early postemergence and late postemergence application, for which weed density was reduced and weed control was improved later in the season. In 2024, when the number of soybean plants was very low due to freeze damage, an early postemergence application of dicamba + glyphosate and a late postemergence application of glyphosate + glufosinate + S-metolachlor resulted in the greatest weed control and yield from the crop that was planted ultra-early. The results from this study indicate that when soybean was planted ultra-early, treatments that included two postemergence applications, particularly those that included a residual herbicide applied at late postemergence, were better suited to maintain weed suppression later in the season and protect soybean yield potential when the soybean plant population was very low and pressure from grass weeds was high.

As sustainability challenges intensify globally, evaluating the environmental impacts of the Belt and Road Initiative (BRI) has become increasingly important. Using panel data from 176 countries spanning 2003–2022, this study examines the influence of BRI on environmental sustainability using ecological footprint per capita (lnEF) as a comprehensive indicator and difference-in-differences (DiD) methodology. BRI participation leads to a 5 per cent increase in the lnEF among partner countries. Dual-channel analysis shows that renewable energy consumption mitigates ecological pressure, whereas information and communication technology development partially mediates the effects of BRI participation and environmental outcomes. Pronounced heterogeneity effects were observed for (i) countries joining between 2016 and 2019 (in Europe, Central Asia, the Middle East and North Africa), and (ii) countries in upper-middle- and high-income groups. Propensity score matching–DiD and robustness checks showed consistent findings. This study offers policy recommendations that emphasize environmental assessments, green technology support and international cooperation on sustainability.

The primordial helium mass fraction, $Y_{p}$, is a key observational pillar of Big Bang nucleosynthesis and a sensitive probe of early-Universe physics. Over the past several decades, numerous observational $Y_{p}$ determinations have been published using a wide range of astrophysical tracers and cosmological techniques. Although recent measurements exhibit striking convergence and increasingly small uncertainties, the statistical and historical context of this consensus has not been examined systematically. Here, we compile and analyse a comprehensive dataset of observational $Y_{p}$ determinations published between the late-1960s and 2022. The final sample comprises 143 reported values spanning multiple tracers. We find clear evidence for long-term convergence in published $Y_{p}$ values, punctuated by statistically significant change points in the mid-2000s and early 2010s. Careful examination reveals that many extragalactic Hii-region determinations are not fully independent, relying on re-analyses or partial reuse of a limited number of observational datasets. This reduces the effective number of independent constraints and provides important context for interpreting the precision of recent results. Our findings do not challenge the overall consistency of modern $Y_{p}$ determinations with standard cosmology, but they underscore the importance of accounting for data dependence, methodological homogeneity and historical evolution when synthesising measurements.