Ball sampling is an active technique of sampling the upper canopy of hemlock, Tsuga sp. (Pinaceae), to detect the nonnative hemlock woolly adelgid, Adelges tsugae Annand (Hemiptera: Adelgidae). We tested a 7.5-cm-diameter wooden ball fitted with Velcro® with a BigShot® slingshot that sends the ball into the upper hemlock canopy. The 7.5-cm ball detected wool with fewer sampling attempts per tree and had a higher detection rate after 10 sampling attempts than a 5-cm wooden ball using a much smaller HyperDog® slingshot did. However, sampling with the 7.5-cm ball took 20% longer per tree and fatigued shooters after only 30–40 shots due to the size and effort required to use the larger slingshot. A larger sampling device (= greater Velcro® surface area) significantly improved detection of adelgid wool and is recommended, provided a more efficient launching system is developed.

Weaning and introduction to a solid diet result in physiological stress in piglets. This can be offset by using complex diets. The terms ‘complexity’ and ‘complex diets’ are used in practice and academia but are not precisely defined. The aim of this review was to identify the ingredients in weaner diets, their inclusion levels and how the number of ingredients or complexity of diets influences weaner performance, intestinal and systemic health, environmental sustainability and antibiotic use. Not all diets are formulated equally. Some prioritise meeting the weaner’s nutritional needs, while other diets seek to align health promotion and adaptation to the environment. As diet composition is of vital importance for young piglets, the components needed in these complex diets must be defined. Healthy, environmentally adapted pigs have excellent growth performance. We therefore recommend use of a new term, ‘gut health supporting diets’, to encompass the many concepts associated with diet complexity.

Ruzsa asked whether there exist Fourier-uniform subsets of $\mathbb Z/N\mathbb Z$ with density $\alpha$ and 4-term arithmetic progression (4-AP) density at most $\alpha^C$, for arbitrarily large C. Gowers constructed Fourier uniform sets with density $\alpha$ and 4-AP density at most $\alpha^{4+c}$ for some small constant $c \gt 0$. We show that an affirmative answer to Ruzsa’s question would follow from the existence of an $N^{o(1)}$-colouring of [N] without symmetrically coloured 4-APs. For a broad and natural class of constructions of Fourier-uniform subsets of $\mathbb Z/N\mathbb Z$, we show that Ruzsa’s question is equivalent to our arithmetic Ramsey question.

We prove analogous results for all even-length APs. For each odd $k\geq 5$, we show that there exist $U^{k-2}$-uniform subsets of $\mathbb Z/N\mathbb Z$ with density $\alpha$ and k-AP density at most $\alpha^{c_k \log(1/\alpha)}$. We also prove generalisations to arbitrary one-dimensional patterns.

Gardens have emerged as a key habitat resource for pollinators in cities, but more research is needed to determine the optimal garden characteristics for maximising native pollinator diversity. Syrphid flies (Diptera: Syrphidae) are abundant generalist fly pollinators that have received less study than other pollinators in urban gardens. In this study, we investigated whether flowering plant diversity and the presence of native plants were related to syrphid abundance and diversity in urban street gardens. Over a two-month period, we sampled 12 small public gardens in a residential urban area (Vancouver, British Columbia, Canada) to explore correlations between plant and syrphid assemblages. Gardens reflected the relative scarcity of native plants in our study system, such that gardens with native flowers present ranged from 10 to 60% cover. Although syrphid abundance and richness varied among gardens, neither floral richness nor the presence of native flowers was correlated with syrphid abundance or diversity. Beyond plant diversity and origin, other characteristics may be more important to syrphid visitation at the garden scale. A better understanding of the role of garden characteristics among the complex factors shaping urban syrphid assemblages will offer valuable insights for the improvement of pollinator conservation strategies.

Housing informality has emerged across developing and developed societies amid the global housing crisis. This article presents an intra-national comparative analysis of informal housing interventions in Hong Kong and Guangzhou, two major Chinese cities, to investigate the policies and discourses of urban housing informality and the factors shaping different governance regimes. A critical policy discourse analysis was conducted on official documents addressing subdivided units in Hong Kong and urban villages in Guangzhou between 2010 and 2023. The analysis focuses on policy goals, interventive measures and state-market-society relations, revealing that despite similarities between subdivided units and urban villages, government interventions differ significantly. The Hong Kong government has adopted a regulatory-welfare-mix model, whereas the Guangzhou government has pursued a developmental approach to address the phenomenon. This article contributes to policy studies by comparing informal housing intervention approaches and analysing the within-country divergence of normative goals and policy levers under different sociopolitical contexts.

This paper traces how geological surveys and prospecting across two centuries shaped Afghanistan’s enduring characterization as a mineral-rich “El Dorado.” By investigating the shift in survey methods from comprehensive terrestrial to aerial reconnaissance, I show how geological knowledge production served purposes far beyond imperial resource identification and extraction. Drawing from historical and ethnographic research, including insights from a current emerald mine operator, I uncover how precious stones’ physical properties and circulating narratives about hidden riches propelled—and continue to propel—a vast network of individuals into mining enterprises: from state authorities and local powerbrokers to foreign geologists, mineral collectors, and international aid organizations. The result is the creation of new narratives about extractable wealth that interweave scientific practices and global market dynamics to transcend conventional periodization such as pre-Soviet, Soviet, and United States. These narratives have emerged from and reinforced asymmetrical relationships in both labor and expertise, ultimately positioning Afghan participants precariously within global mineral markets, made riskier still in times of conflict.

In the advanced era of compact and convenient devices, electromagnetic microwave brain imaging systems have emerged as substitutes for large and bulky imaging devices such as X-rays, CT scans, MRIs, and ultrasounds for diagnosing brain disorders. This article introduces a compact monopole antenna specifically tailored for microwave imaging in brain stroke detection. The bidirectional antenna incorporates a triple hollow rectangular patch and a hexagonal slotted ground for enhanced performance. The antenna is constructed on an FR-4 substrate with a thickness of 1.6 mm. The design is finalized using CST, with parameters adjusted to achieve the desired bandwidth and gain performance. The antenna provides a bandwidth of 2.16 GHz, spanning from 1.35 to 3.51 GHz, with a return loss |S11| < 10 dB (VSWR < 2) and a peak gain of 5.1 dBi at 3.5 GHz, while maintaining stable radiation characteristics across the entire frequency range. Simulation results indicate that the proposed antenna is well-suited for microwave-based brain stroke detection and imaging applications. The fabricated antenna has been tested for brain stroke detection with an innovative setup in the lab. It is observed that the stroke models have been detected clearly.

This paper presents an efficient trajectory planning method for a 4-DOF robotic arm designed for pick-and-place manipulation tasks. The method addresses several challenges, where traditional optimization approaches struggle with high dimensionality, and data-driven methods are costly to collect enough data. The proposed approach leverages Bézier curves for computationally efficient, smooth trajectory generation, minimizing abrupt changes in motion. When continuous solutions for the end-effector angle are unavailable, joint angles are interpolated using Bézier or Hermite interpolation. Additionally, we use custom metrics to evaluate deviation between the interpolated trajectory and the original trajectory, as well as the overall smoothness of the path. When a continuous solution exists, the trajectory is treated as a Gaussian process, where a prior factor is generated using the centerline. This prior is then combined with a smoothness factor to optimize the trajectory, ensuring it remains as smooth as possible within the feasible solution space through stochastic gradient descent. The method is evaluated through simulations in Nvidia Isaac Sim; results highlight the method’s suitability, and future work will explore enhancements in prior trajectory integration and smoothing techniques.

A quadrotor was modified by adding wings to the frame to directly compare the flight dynamics characteristics as well as the stability and control derivatives of the quadrotor and its biplane tailsitter variant. The on-axis response of the quadrotor and a biplane tailsitter variant were measured through flight tests, and a frequency domain system identification was used for non-parametric and parametric model identification. Identification of the full vehicle dynamics also demonstrated that identifying the motor torque and back-EMF constants from no-load measurements and the remaining motor parameters from a rotor-motor test stand provided the most accurately identified full vehicle model. The motor dynamics were shown to add a pole to the thrust-based responses (roll, pitch and heave), while the torque-based response (yaw) included a pole and a zero. This approach was then used to identify and compare the quadrotor dynamics, tailsitter dynamics and the total impact of canting the motors. It was found that the presence of the wing added pitch damping to the dynamics and pitch stability became negative. The yaw axis saw an increase in yaw damping derivative, and a reduction in the yaw control derivative to the point where it became difficult to control the aircraft. By introducing cant, both the quadrotor and tailsitter saw large increases in the yaw control derivative. Further, the rotor thrust-based moment generation due to cant resulted in the yaw response zero being canceled by the motor dynamics, resulting in a purely first-order yaw response. Neither the wing nor cant produced any change in the lateral and heave axes.

Online platforms and activities, including smartphones, computers, social media, video games and applications involving artificial intelligence, have become a regular part of daily life and offer individuals a wide range of benefits. The purpose of this document is to increase psychiatrists’ awareness of the frequency and potential risks associated with excessive internet use, and to emphasise the need for psychiatrists to routinely question patients about their online activities. Internet use may become excessive and result in both psychological distress and physical impairments. Treatments and countermeasures may be required to address the harmful consequences of excessive internet use. Psychiatrists should be aware of patient online activities. Understanding of a patient’s online behaviour should now be a routine part of a psychiatric interview.

For years, Thomists have debated Aquinas’s view on the status of human beings or persons between death and resurrection. Survivalists hold that, for Aquinas, the survival of the separated soul is sufficient for the continued existence of the human being; corruptionists deny this, insisting that the body is also necessary for a human being to exist, absolutely speaking. Most survivalists agree that matter is part of a human being’s nature, signified by its essential definition. So how can a human being survive the loss of its body at death? Many survivalists reply that a thing’s essence and definition only express what it is naturally, or normally, or typically, but not necessarily. In this paper, I argue that this view of essences and definitions is not Aquinas’s own. This comes out clearly in Aquinas’s treatments of God’s absolute power, which he thinks is limited only by logical contradiction. In such treatments, Aquinas consistently appeals to the natures of things to explain why not even God can make things to be other than they are by definition, on pain of logical contradiction. This shows that he thinks of a thing’s essence and definition as strictly necessary, not merely normative, for its existence.

In this paper, I propose a new method called the auxiliary state method (ASM) for solving highly nonlinear dynamic stochastic general equilibrium (DSGE) models with state variables that exhibit a non-elliptical ergodic distribution. The ASM method effectively avoids most improbable states that, while never visited, can create issues for numerical methods. I then demonstrate the ASM method by applying it to a model with highly asymmetric nominal rigidities, which are necessary to match the skewness of the U.S. inflation distribution. The ASM method can handle the high level of asymmetry, whereas the standard projection method cannot. Additionally, the ASM method is significantly faster than the standard projection method.