A surge of Mittie Glacier, a 50 km-long tidewater outlet glacier of Manson Icefield, occurred between approximately 1992 and 2007. Velocities increased slowly at first, but then increased rapidly to reach a peak of 4800 m a−1 in early 1996, the highest ever reported for a glacier in the Canadian Arctic. The surge initiated at the terminus and propagated up-glacier, with a maximum terminus advance of 7.3 km between 1994 and 1999. The surge was almost entirely restricted to the lower ~30 km of the glacier, in a region which radio-echo sounding shows to be grounded below sea level. A 3 km-wide crevasse with a 150 m opening occurred at the separation between faster moving ice downstream and slower moving ice upstream. Surge initiation appears to have been triggered by flotation of the lower terminus, caused by long-term thinning of this region during quiescence.

Let Mn and Tn denote the nth Motzkin number and the nth central trinomial coefficient respectively. We prove that for any prime $p\ge 5$,

\begin{equation*}\begin{aligned}\\[-22pt]&\sum_{k=0}^{p-1}M_k^2\equiv \left(\frac{p}{3}\right)\left(2-6p\right)\pmod{p^2},\\&\sum_{k=0}^{p-1}kM_k^2\equiv \left(\frac{p}{3}\right)\left(9p-1\right)\pmod{p^2},\\&\sum_{k=0}^{p-1}T_kM_k\equiv \frac{4}{3}\left(\frac{p}{3}\right)+\frac{p}{6}\left(1-9\left(\frac{p}{3}\right)\right)\pmod{p^2},\\[-6pt]\end{aligned}\end{equation*}

where $\left(-\right)$ is the Legendre symbol. These results confirm three supercongruences conjectured by Z.-W. Sun in 2010.

This research investigates the wake–foil interactions between two oscillating foils in a tandem configuration undergoing energy harvesting kinematics. Oscillating foils have been shown to extract hydrokinetic energy from free-stream flows through a combination of periodic heave and pitch motions, at relatively higher amplitudes and lower reduced frequency than thrust generating foils. When placed in tandem, the wake–foil interactions can govern the energy harvesting efficiency of the system due to a reduced relative flow velocity in combination with a structured and coherent wake of vortices shed from the high amplitude flapping of upstream foils. This work utilizes simulations of two tandem foils to parameterize and model the energy harvesting performance as a function of array configuration and foil kinematics. Once the wake of the leading foil has been fully parameterized, the placement, phase angle and kinematic stroke of the second foil is utilized to estimate the time-dependent power curve. The algorithm predicts the power of the second foil through the mean and unsteady wake characteristics, including the direct impingement of a vortex with the trailing foil.

To deeply explore the solar system, it will be necessary to become less reliant on the resupply tether to Earth. An approach explored in this study is to convert hydrocarbons in asteroids to human edible food. After comparing the experimental pyrolysis breakdown products, which were able to be converted to biomass using a consortia, it was hypothesized that equivalent chemicals found on asteroids could also be converted to biomass with the same nutritional content as the pyrolyzed products. This study is a mathematical exercise that explores the potential food yield that could be produced from these methodologies. This study uses the abundance of aliphatic hydrocarbons in the Murchison meteorite (>35 ppm) as a baseline for the calculations, representing the minimum amount of organic matter that could theoretically be attributed to biomass production. Calculations for the total carbon in solvent-insoluble organic matter (IOM) represent the maximum amount of organic matter that could theoretically be attributed to food production. These two values will provide a range of realistic yields to determine how much food could theoretically be extractable from an asteroid. The results of this study found that if only the aliphatic hydrocarbons can be converted into biomass (minimum scenario) the resulting mass of edible biomass extractable from asteroid Bennu ranges from 5.070 × 107 g to 2.390 × 108 g. If the biomass extraction process, however, is more efficient, and all IOM is converted into edible biomass (maximum scenario), then the mass of edible biomass extractable from asteroid Bennu ranges from 1.391 × 109 g to 6.556 × 109 g. This would provide between 5.762 × 108 and 1.581 × 1010 calories that is enough to support between 600 and 17 000 astronaut life years. The asteroid mass needed to support one astronaut for one year is between 160 000 metric tons and 5000 metric tons. Based on these results, this approach of using carbon in asteroids to provide a distributed food source for humans appears promising, but there are substantial areas of future work.

With the ongoing negotiations for an international legally binding instrument on plastic pollution, including in the marine environment, and the frustration at the end of Intergovernmental Negotiating Committee (INC-3), analyzing the zero draft text, which formed the basis for this negotiation round, is crucial. This analysis examines to what extent the zero draft conveys a clear problem definition as the foundation for an internationally legally binding instrument on plastic pollution. We find that the draft lacks a clear problem definition. Additionally, we investigate how the zero draft balances the focus between marine environments and other affected areas and discusses the implications for governance strategies. We find that the draft focuses particularly on fishing gear and hence has a downstream perspective, while upstream measures are equally important. Furthermore, this study delves into the key motivations driving the treaty negotiations, revealing that health and environmental concerns predominate. In comparing our results with previous research, we align with recent publications analyzing INC submissions and onsite statements. In addition, we identify significant differences in key motivations to tackle the plastic pollution issues between the EU and the international level. These disparities, evident in how health and economic arguments are prioritized, reflect varied approaches to combating plastic pollution across political spheres.

Iguaçu National Park, a UNESCO World Heritage Site, faces threats from proposed legislation aimed at downgrading its protection to allow reopening of the Caminho-do-Colono road, which would fragment the National Park. This study assesses the National Park’s importance in preserving native vegetation and its economic significance via payments for environmental services. We evaluated different scenarios, demonstrating how these resources are vital for certain municipalities. By comparing economic performance before and after the road’s closure, our findings reveal that, contrary to local beliefs, the closure did not negatively impact the local economy. Additionally, these legislative bills are legally infeasible and fail to offer environmental or economic benefits, favouring small interest groups over the collective good. This research highlights that the Caminho-do-Colono road is not a viable approach to municipal development. Instead, maintaining the National Park’s integrity is crucial for both ecological preservation and economic stability in the region. Our analysis underscores the broader implications of environmental conservation efforts and the necessity of rejecting projects that compromise protected areas. This study provides a comprehensive evaluation of the National Park’s role, emphasizing the need for sustainable development that aligns with environmental and community well-being.

A numerical method is proposed for a class of one-dimensional stochastic control problems with unbounded state space. This method solves an infinite-dimensional linear program, equivalent to the original formulation based on a stochastic differential equation, using a finite element approximation. The discretization scheme itself and the necessary assumptions are discussed, and a convergence argument for the method is presented. Its performance is illustrated by examples featuring long-term average and infinite horizon discounted costs, and additional optimization constraints.

This paper calls for the lawyering profession – which is often viewed as unabridged – to be reframed into two distinct occupations: legal aid practice and private practice, to better incorporate the divisions in labour. In order to better understand contemporary legal aid work and its workers, the hidden realities must be unveiled from behind their private counterparts, which opposingly signify wealth, professionalism, autonomy and privilege. Set within a context of crumbling professional identities, a shrinking industry and financial constraints, the paper draws on ethnographic and interview data. It finds that those working in legal aid undoubtedly face a more stagnated, under-resourced and precarious working environment, which means that their professional experience is vastly different from their private counterparts. Likewise, those in the field face toxic narratives from the government, the media, the public, and their private counterparts alike, resulting in persistent discourse of vilification. Ultimately, it calls for a refocus of legal aid work as a separate vocation due to its altruistic underpinnings, unique ‘professional’ identity, and values.

Associations between adversity and youth psychopathology likely vary based on the types and timing of experiences. Major theories suggest that the impact of childhood adversity may either be cumulative in type (the more types of adversity, the worse outcomes) or in timing (the longer exposure, the worse outcomes) or, alternatively, specific concerning the type (e.g., parenting, home, neighborhood) or the timing of adversity (e.g., specific developmental periods). In a longitudinal sample from the Future of Families and Wellbeing Study (N = 4,210), we evaluated these competing hypotheses using a data-driven structured life-course modeling approach using risk factors examined at child age 1 (infancy), 3 (toddlerhood), 5 (early childhood), and 9 (middle childhood). Results showed that exposures to more types of adversity for longer durations (i.e., cumulative in both type and timing) best predicted youth psychopathology. Adversities that occurred at age 9 were better predictors of youth psychopathology as compared to those experienced earlier, except for neglect, which was predictive of internalizing symptoms when experienced at age 3. Throughout childhood (across ages 1–9), aside from the accumulation of all adversities, parental stress and low collective efficacy were the strongest predictors of internalizing symptoms, whereas psychological aggression was predictive of externalizing symptoms.

The Qing dynasty enforced a policy of separate governance for the people of the Eight Banners, ruling that bannermen were neither to be administered under the regular civilian administrative system, nor listed on the civilian register. Institutionally and legally, the labels “Banner” (qi 旗) and “civilian” (min 民) marked a fundamental divide between different social groups in the Qing. However, in actual practice, the boundary between the two was less rigid. An ambiguous area existed within the seemingly strict legal and administrative regime, providing opportunists with an abundance of loopholes to exploit. Some changed their status from “civilian commoner” to “bannermen” to acquire land, while others moved from “bannermen” status to “civilian commoner” status to pursue promotion in the civil service. Shedding light on the everyday lives of these people, this article delves into the intricate Banner–civilian classification of the Qing dynasty, with a focus on the overlapping area between the parallel systems. It aims to rectify the conventional binary perspective that strictly dichotomizes Banner and civilian status. By doing so, it highlights the multifaceted nature and diversity inherent in Qing ethnic relations and local society.

The spatial evolution of various statistical parameters of fetch-limited waves generated by steadily blowing wind over mean water flow in a wind-wave flume is investigated experimentally. Measurements are performed in both along- and against-wind current conditions, and compared with measurements in the absence of current. A rake of capacitance-type wave gauges is used to measure surface elevation for a wide range of wind and water current velocities; additionally, an optical wave gauge is used to measure the directional properties of the wind-wave field in the presence of a mean water current at multiple locations. The variation with fetch of essential wave parameters such as characteristic wave energy, dominant frequency, power spectra and temporal coherence, as well as higher-order statistical moments that characterize wave shape, is presented for co- and counter-wind water currents, and compared with the no-current condition. The findings in the presence of mean water flow are interpreted in the framework of the viscous shear flow instability model of Geva & Shemer (Phys. Rev. Lett., vol. 128, 2022, 124501).

Utilizing online survey data of US consumers, this study examines the extent to which consumers' acceptance of genetically modified (GM) and gene-edited (GE) food is driven by their risk attitudes. Our results indicate that individuals with high-risk propensity are more likely to accept both GM and GE food than individuals with low- and medium-risk propensity. Our results also find differences in consumers' attitudes toward plants and animal products in the context of both GM and GE. Intriguingly, these attitudinal differences can be explained by consumers' risk propensities. Specifically, both low- and medium-risk propensity consumers differentiate between plants and animal products; the latter is less acceptable than the former, indicating a tendency to have more concerns about the application of biotechnology to animals than plants. However, individuals with high-risk propensity do not differentiate between GM and GE plants and animal products. Our results suggest that policymakers, the food industry, and researchers need to consider these attitudinal differences while studying consumer attitudes toward GM and GE food. Failing to capture these attitudinal differences in studies focusing on consumer behavior toward GM and GE food may result in either overestimating or underestimating consumer response.

We investigate some aspects of the problem of the estimation of birth distributions (BDs) in multi-type Galton–Watson trees (MGWs) with unobserved types. More precisely, we consider two-type MGWs called spinal-structured trees. This kind of tree is characterized by a spine of special individuals whose BD $\nu$ is different from the other individuals in the tree (called normal, and whose BD is denoted by $\mu$). In this work, we show that even in such a very structured two-type population, our ability to distinguish the two types and estimate $\mu$ and $\nu$ is constrained by a trade-off between the growth-rate of the population and the similarity of $\mu$ and $\nu$. Indeed, if the growth-rate is too large, large deviation events are likely to be observed in the sampling of the normal individuals, preventing us from distinguishing them from special ones. Roughly speaking, our approach succeeds if $r\lt \mathfrak{D}(\mu,\nu)$, where r is the exponential growth-rate of the population and $\mathfrak{D}$ is a divergence measuring the dissimilarity between $\mu$ and $\nu$.