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Abstract 4D printing technology enables the fabrication of constructs capable of shape transformation when exposed to external stimuli. Epoxy‐based shape memory polymers (SMPs) have shown great potential for various 4D printing applications. However, due to their thermocurable nature, the fabrication of 4D constructs using epoxy‐based materials is often limited to a mold casting strategy, limiting design flexibility and often yielding flat structures. In this work, photocurable smart 4D inks are developed by integrating polyethylene glycol diacrylate (PD) into epoxy‐based materials. These inks undergo a two‐step crosslinking process: i) photocuring of the PD network, and ii) thermocuring of the SMP, resulting in an interpenetrating polymer network (IPN). The inclusion of PD in the 4D inks not only enables the formation of complex shapes via the restructuring step but also allows for fine‐tuning of mechanical properties and thermal responsiveness. Additionally, these inks offered greater versatility in employable fabrication techniques, including mold casting, photolithography, and stereolithography (SLA). 

ABSTRACT The cerebral cortex accounts for substantial energy expenditure, primarily driven by the metabolic demands of synaptic signaling. Mitochondria, the organelles responsible for generating cellular energy, play a crucial role in this process. We investigated ultrastructural characteristics of the primary visual cortex in 18 phylogenetically diverse mammals, spanning a broad range of brain sizes from mouse to elephant. Our findings reveal remarkable uniformity in synapse density, postsynaptic density (PSD) length, and mitochondria density, indicating functional and metabolic constraints that maintain these fundamental features. Notably, we observed an average of 1.9 mitochondria per synapse across mammalian species. When considered together with the trend of decreasing neuron density with larger brain size, we find that brain enlargement in mammals is characterized by increasing proportions of synapses and mitochondria per cortical neuron. These results shed light on the adaptive mechanisms and metabolic dynamics that govern cortical ultrastructure across mammals. 

Abstract Climate‐driven ecosystem shifts occur through turnover in the foundation species which structure the landscape. Therefore, to predict the fate of areas undergoing climate‐driven ecosystem shifts, one approach is to characterize ecological and evolutionary responses of foundation species along dynamic environmental gradients. One such gradient is the ecotone between tidal marshes and maritime forests in coastal areas of the US Mid‐Atlantic region where accelerated sea‐level rise and coastal storms of increased frequency and intensity are driving forest dieback and inland marsh migration. Mid‐Atlantic tidal marshes are structured by marsh grasses which act as foundation species, and these grasses exhibit trait variation across their distribution from established marsh interior to their inland migration front. We conducted a reciprocal transplant experiment withSpartina patens, a dominant high marsh grass and foundation species, between established populations in the high marsh and range edge populations in the forest understory at three Mid‐Atlantic sites. We monitored environmental conditions in marsh and forest understory habitats, measured plant traits (above‐ and belowground biomass, specific leaf area, leaf N and C concentrations) in transplanted and reference non‐transplanted individuals, and used microsatellite markers to determine the genetic identity of transplants to quantify clonality between habitats and sites. Individuals transplanted into the forest understory exhibited a plastic shift in resource allocation to aboveground structures associated with light acquisition, with shifts in transplants making them more morphologically similar to reference individuals sampled from the forest habitat. Clonal diversity and genetic distance among transplants were relatively high at two of three sites, but individuals at all sites exhibited trans‐habitat plasticity regardless of clonal diversity or a lack thereof. Individuals grown in the forest understory showed lower vegetative and reproductive fitness. Nevertheless, the trait plasticity exhibited by this species allowed individuals from the forest that were transplanted into the marsh to recoup significant biomass in only a single growing season. We predict high plasticity will facilitate the persistence of colonizingS. patensindividuals under suboptimal forest shade conditions until forest dieback increases light availability, ultimately promoting continued inland migration of this foundation species under sea‐level rise. 

Abstract We give uniform formulae for the number of full reflection factorizations of a parabolic quasi‐Coxeter element in a Weyl group or complex reflection group, generalizing the formula for the genus‐0 Hurwitz numbers. This paper is the culmination of a series of three. 

ABSTRACT Alzheimer's disease (AD) and its associated pathology have been primarily identified in humans, who have relatively large brains and long lifespans. To expand what is known about aging and neurodegeneration across mammalian species, we characterized amyloid‐beta (Aβ) and tau lesions in five species of aged felids (n= 9; cheetah, clouded leopard, African lion, serval, Siberian tiger). We performed immunohistochemistry to detect Aβ40 and Aβ42 in plaques and vessels and hyperphosphorylated tau in the temporal lobe gyrus sylvius and in the CA1 and CA3 subfields of the hippocampus. We also quantified the densities and morphological types of microglia expressing IBA1. We found that diffuse Aβ42 plaques, but not dense‐core plaques, were present more frequently in the temporal cortex and tended to be more common than Aβ40 plaques across species. Conversely, vascular Aβ was labeled more consistently with Aβ40 for each species on average. Although all individuals showed some degree of Aβ40 and/or Aβ42 immunoreactivity, only the cheetahs and clouded leopards exhibited intraneuronal hyperphosphorylated tau (i.e., pretangles), which was more common in the hippocampus. Reactive, intermediate microglia were significantly associated with total Aβ40 vessel area and pretangle load in the hippocampus. This study demonstrates the co‐occurrence of Aβ and tau pathology in two felid species, cheetahs and clouded leopards. Overall, these results provide an initial view of the manifestation of Aβ and tau pathology in aged, large‐brained felids, which can be compared with markers of neurodegeneration across different taxa, including domestic cats, nonhuman primates, and humans. 

ABSTRACT The nucleus accumbens (NAcc) and ventral pallidum (VP) are key nodes in the mesolimbic reward pathway that facilitate stimulus salience, including the regulation of social motivation and attachment. Primate species display variation in social behaviors, including different levels of impulsivity, bonding, and aggression. Previous research has implicated neuromodulation of the reward pathway in the differential expression of various social behaviors, suggesting that differences in neurotransmitter innervation may play a role in species‐specific patterns. To explore this, we examined serotonergic innervation in the NAcc and VP among primates. We used stereology to quantify serotonin transporter‐immunoreactive (SERT‐ir) axon length density in the NAcc and VP of 13 primate species, including humans, great apes, and cercopithecid and platyrrhine monkeys. Our data show that serotonergic innervation density within both the NAcc and VP is highly conserved among species. This finding contrasts with our previous findings of higher levels of SERT‐ir axons in the dorsal striatum of humans and great apes relative to monkeys, a human‐specific increase in dopaminergic innervation within the NAcc and VP, and a human‐specific increase of neuropeptide Y in the NAcc, highlighting the mosaic nature of innervation patterns among species. 

Abstract The ability to withstand and recover from disruptions is essential for seaport energy systems, and in light of the growing push for decarbonization, incorporating clean energy sources has become increasingly imperative to ensure resilience. This paper proposes a resilience enhancement planning strategy for a seaport multi‐energy system that integrates various energy modalities and sources, including heating, cooling, hydrogen, solar, and wind power. The planning strategy aims to ensure the reliable operation of the system during contingency events, such as power outages, equipment failures, or extreme weather incidents. The proposed optimization model is designed as a mixed‐integer nonlinear programming formulation, in which McCormick inequalities and other linearization techniques are utilized to tackle the model nonlinearities. The model allocates fuel cell electric trucks (FCETs), renewable energy sources, hydrogen refueling stations, and remote control switches such that the system resilience is enhanced while incorporating natural‐gas‐powered combined cooling, heating, and power system to minimize the operation and unserved demand costs. The model considers various factors such as the availability of renewable energy sources, the demand for heating, cooling, electricity, and hydrogen, the operation of remote control switches to help system reconfiguration, the travel behaviour of FCETs, and the power output of FCETs via vehicle‐to‐grid interface. The numerical results demonstrate that the proposed strategy can significantly improve the resilience of the seaport multi‐energy system and reduce the risk of service disruptions during contingency scenarios. 

Abstract Transparent microelectrodes have received much attention from the biomedical community due to their unique advantages in concurrent crosstalk‐free electrical and optical interrogation of cell/tissue activity. Despite recent progress in constructing transparent microelectrodes, a major challenge is to simultaneously achieve desirable mechanical stretchability, optical transparency, electrochemical performance, and chemical stability for high‐fidelity, conformal, and stable interfacing with soft tissue/organ systems. To address this challenge, we have designed microelectrode arrays (MEAs) with gold‐coated silver nanowires (Au–Ag NWs) by combining technical advances in materials, fabrication, and mechanics. The Au coating improves both the chemical stability and electrochemical impedance of the Au–Ag NW microelectrodes with only slight changes in optical properties. The MEAs exhibit a high optical transparency >80% at 550 nm, a low normalized 1 kHz electrochemical impedance of 1.2–7.5 Ω cm², stable chemical and electromechanical performance after exposure to oxygen plasma for 5 min, and cyclic stretching for 600 cycles at 20% strain, superior to other transparent microelectrode alternatives. The MEAs easily conform to curvilinear heart surfaces for colocalized electrophysiological and optical mapping of cardiac function. This work demonstrates that stretchable transparent metal nanowire MEAs are promising candidates for diverse biomedical science and engineering applications, particularly under mechanically dynamic conditions.