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Abstract This article addresses the kinematic control of a redundant soft robotic arm. Full pose kinematic control of soft robots is challenging because direct application of the classical controllers developed based on rigid robots to soft robots could lead to unreliable or infeasible motions. In this study, we explore the manipulability property of a soft robotic arm and develop an advanced resolved-rate controller that prioritizes position over orientation control and switches its modes and gains based on position and orientation manipulabilities, enabling stable motion even when the robot is close to the singular configurations. The simulation and experimental results indicate that our proposed method outperforms previous methods in terms of both accuracy and smoothness during operation. 

Ultrastripped and Type Ibn supernovae (USSNe and SNe Ibn, respectively) are fast-evolving, hydrogen-poor transients that often show signs of interaction with dense circumstellar material (CSM). S. C. Wu & J. Fuller identify a mass range for helium-core stars in which they expand significantly during core oxygen/neon burning, resulting in extreme late-stage mass loss in tight binaries (P∼ 1–100 days). Here we explore the resulting light curves from a subset of models from S. C. Wu & J. Fuller and find that in some cases they can exhibit two phases of shock cooling emission (SCE). The first SCE is attributed to the circumbinary material, and the second is from the extended helium-burning envelope of the exploding star. Since SCE luminosity is roughly proportional to the initial radius of the emitting material, events that exhibit both phases of SCE provide the exciting opportunity of measuring both the extent of the CSM and the radius of the exploding star. These light curves are explored with both analytic arguments and numerical modeling, and from this we identify the parameter space of CSM mass, helium envelope (HE) mass, and nickel mass, for which the HE SCE will be visible. We provide a qualitative comparison of these models to two fast-evolving, helium-rich transients, SN 2019kbj and SN 2019dge. The similarity between these events and our models demonstrates that this extreme binary mass loss mechanism may explain some SNe Ibn and USSNe. 

APLU’s Charting and Expanding Needed Trails to Research Administration and Leadership (CENTRAL) Conference, convened partners from across the senior research leadership ecosystem to fulfill two key goals to enhance the professional development of Senior Research Officers (e.g. Vice Presidents of Research). First, attendees identified key paths that individuals take to arrive at senior research leadership roles, recognizing the breadth of potential pathways. Second, attendees identified the skillsets, opportunities, and barriers relevant to pursuing careers in senior research leadership. This U.S. NSF-funded conference (Award # 2324469) was a collaboration between APLU, NORDP, ARIS, and Alabama A&M University and led by PI Kevin C. Cooke. Supplementary materials, including the full proceedings report and executive summary, can be found here: https://www.aplu.org/our-work/2-fostering-research-innovation/nsf-granted-central-conference/ 

Climate warming can induce a cost-of-living “squeeze” in ectotherms by increasing energetic expenditures while reducing foraging gains. We used biophysical models (validated by 2685 field observations) to test this hypothesis for 10 ecologically diverse lizards in African and Australian deserts. Historical warming (1950–2020) has been more intense in Africa than in Australia, translating to an energetic squeeze for African diurnal species. Although no net impact on Australian diurnal species was observed, warming generated an energetic “relief” (by increasing foraging time) for nocturnal species. Future warming impacts will be more severe in Africa than in Australia, requiring increased rates of food intake (+10% per hour active for diurnal species). The effects of climate warming on desert lizard energy budgets will thus be species-specific but potentially predictable. 

Understanding the relationship between the environment parents experience during reproduction and the environment embryos experience in the nest is essential for determining the intergenerational responses of populations to novel environmental conditions. Thermal stress has become commonplace for organisms inhabiting areas affected by rising temperatures. Exposure to body temperatures that approach, but do not exceed, upper thermal limits often induces adverse effects in organisms, but the propensity for these temperatures to have intergenerational consequences has not been explored in depth. Here, we quantified the effects of thermal stress on the reproductive physiology and development of brown anoles (Anolis sagrei) when thermal stress is experienced by mothers and by eggs during incubation.Mothers exposed to thermal stress produced smaller eggs and smaller offspring with reduced growth rates, while egg stress reduced developmental time and offspring mass. Hatchling survival and growth were negatively affected by thermal stress experienced by mothers but not by thermal stress experienced as eggs. We found mixed evidence for an additive effect of thermal stress on offspring; rather, thermal stress had specific (and most often negative) effects on different components of offspring phenotypes and fitness proxies when experienced either by mothers or by eggs. Stressful body temperatures therefore can function in a similar manner to other types of maternal effects in reptiles; however, this maternal effect has predominantly negative consequences on offspring. 

Abstract Alongside the population of several hundred radio millisecond pulsars currently known in Milky Way globular clusters, a subset of six slowly spinning pulsars (spin periods 0.3–4 s) are also observed. With inferred magnetic fields ​​​​​​≳10¹¹G and characteristic ages ≲​​​​​​10⁸yr, explaining the formation of these apparently young pulsars in old stellar populations poses a major challenge. One popular explanation is that these objects are not actually young but instead have been partially spun up via accretion from a binary companion. In this scenario, accretion in a typical low-mass X-ray binary (LMXB) is interrupted by a dynamical encounter with a neighboring object in the cluster. Instead of complete spin-up to millisecond spin periods, the accretion is halted prematurely, leaving behind a “partially recycled” neutron star. In this Letter, we use a combination of analytic arguments motivated by LMXB evolution andN-body simulations to show that this partial recycling mechanism is not viable. Realistic globular clusters are not sufficiently dense to interrupt mass transfer on the short timescales required to achieve such slow spin periods. We argue that collapse of massive white dwarfs and/or neutron star collisions are more promising ways to form slow pulsars in old globular clusters. 

Bifidobacteria represent a dominant constituent of human gut microbiomes during infancy, influencing nutrition, immune development, and resistance to infection. Despite interest in bifidobacteria as a live biotic therapy, our understanding of colonization, host-microbe interactions, and the health-promoting effects of bifidobacteria is limited. To address these major knowledge gaps, we used a large-scale genetic approach to create a mutant fitness compendium in Bifidobacterium breve. First, we generated a high-density randomly barcoded transposon insertion pool and used it to determine fitness requirements during colonization of germ-free mice and chickens with multiple diets and in response to hundreds of in vitro perturbations. Second, to enable mechanistic investigation, we constructed an ordered collection of insertion strains covering 1,462 genes. We leveraged these tools to reveal community- and diet-specific requirements for colonization and to connect the production of immunomodulatory molecules to growth benefits. These resources will catalyze future investigations of this important beneficial microbe.