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The retina is comprised of diverse neural networks, signaling from photoreceptors to ganglion cells to encode images. The synaptic connections between these retinal neurons are crucial points for information transfer; however, the input-output relations of many synapses are understudied. Starburst amacrine cells in the retina are known to contribute to retinal motion detection circuits, providing a unique window for understanding neural computations. We examined the dual transmitter release of GABA and acetylcholine from starburst amacrine cells by optogenetic activation of these cells, and conducted patch clamp recordings from postsynaptic ganglion cells to record excitatory and inhibitory postsynaptic currents (EPSCs and IPSCs). As starburst amacrine cells exhibit distinct kinetics in response to objects moving in a preferred or null direction, we mimicked their depolarization kinetics using optogenetic stimuli by varying slopes of the rising phase. The amplitudes of EPSCs and IPSCs in postsynaptic ganglion cells were reduced as the stimulus rising speed was prolonged. However, the sensitivity of postsynaptic currents to the stimulus slope differed. EPSC amplitudes were consistently reduced as the steepness of the rising phase fell. By contrast, IPSCs were less sensitive to the slope of the stimulus rise phase and maintained their amplitudes until the slope became shallow. These results indicate that distinct synaptic release mechanisms contribute to acetylcholine and GABA release from starburst amacrine cells, which could contribute to the ganglion cells’ direction selectivity.

Varroa destructor is a major threat for apiculture worldwide. A successful approach to control this parasite must include the application of effective treatments at the correct time. To understand the effect that treatment timing has on Varroa populations at different seasons, we conducted an experiment using a dataset comprising two separate field trials over multiple years, both trials containing four apiary sites composed of 20 honey bee colonies across an area representative of north central Florida environments. Before the start of the season, colonies were treated with two acaricides simultaneously to bring the Varroa populations to ∼0.25 mites/100 bees. Following treatment, we monitored the mite populations monthly via alcohol washes. Our results show that the temporal efficacy of Varroa treatments varies across seasons. We observed that it takes about 4–5 months after treatment in winter and spring for mite populations to return to the standard economical threshold (3 mites/100 bees). Nevertheless, there is a steeper increase in mite populations (

Metal polymer composites combining low density, high strength composites with highly ductile and tough metals have gained traction over the last few decades as lightweight and high-performance materials for industrial applications. However, the mechanical properties are limited by the interfacial bonding strength between metals and polymers achieved through adhesives, welding, and surface treatment processes. In this paper, a novel manufacturing process combining additive manufacturing and compression molding to obtain hybrid metal polymer composites with enhanced mechanical properties is presented. Additive manufacturing enabled deposition of polymeric material with fibers in a predetermined pattern to form tailored charge or preform for compression molding. A grade 300 maraging steel triangular lattice is first fabricated using AddUp FormUp350 laser powder bed system and compression overmolded with additively manufactured long carbon fiber-reinforced polyamide-6,6 (40% wt. CF/PA66) preform. The fabricated hybrid metal polymer composites showed high stiffness and tensile strength. The stiffness and failure characteristics determined from the uniaxial tensile tests were correlated to a finite element model within 20% deviation. Fractographic analyses was performed using microscopy to investigate failure mechanisms of the hybrid structures.

Summary: Retinal bipolar cells are second-order neurons that transmit basic features of the visual scene to postsynaptic partners. However, their contribution to motion detection has not been fully appreciated. Here, we demonstrate that cholinergic feedback from starburst amacrine cells (SACs) to certain presynaptic bipolar cells via alpha-7 nicotinic acetylcholine receptors (α7-nAChRs) promotes direction-selective signaling. Patch clamp recordings reveal that distinct bipolar cell types making synapses at proximal SAC dendrites also express α7-nAChRs, producing directionally skewed excitatory inputs. Asymmetric SAC excitation contributes to motion detection in On-Off direction-selective ganglion cells (On-Off DSGCs), predicted by computational modeling of SAC dendrites and supported by patch clamp recordings from On-Off DSGCs when bipolar cell α7-nAChRs is eliminated pharmacologically or by conditional knockout. Altogether, these results show that cholinergic feedback to bipolar cells enhances direction-selective signaling in postsynaptic SACs and DSGCs, illustrating how bipolar cells provide a scaffold for postsynaptic microcircuits to cooperatively enhance retinal motion detection.

The retina and the olfactory bulb are the gateways to the visual and olfactory systems, respectively, similarly using neural networks to initiate sensory signal processing. Sensory receptors receive signals that are transmitted to neural networks before projecting to primary cortices. These networks filter sensory signals based on their unique features and adjust their sensitivities by gain control systems. Interestingly, dopamine modulates sensory signal transduction in both systems. In the retina, dopamine adjusts the retinal network for daylight conditions (“light adaptation”). In the olfactory system, dopamine mediates lateral inhibition between the glomeruli, resulting in odorant signal decorrelation and discrimination. While dopamine is essential for signal discrimination in the olfactory system, it is not understood whether dopamine has similar roles in visual signal processing in the retina. To elucidate dopaminergic effects on visual processing, we conducted patch-clamp recording from second-order retinal bipolar cells, which exhibit multiple types that can convey different temporal features of light. We recorded excitatory postsynaptic potentials (EPSPs) evoked by various frequencies of sinusoidal light in the absence and presence of a dopamine receptor 1 (D1R) agonist or antagonist. Application of a D1R agonist, SKF-38393, shifted the peak temporal responses toward higher frequencies in a subset of bipolar cells. In contrast, a D1R antagonist, SCH-23390, reversed the effects of SKF on these types of bipolar cells. To examine the mechanism of dopaminergic modulation, we recorded voltage-gated currents, hyperpolarization-activated cyclic nucleotide-gated (HCN) channels, and low-voltage activated (LVA) Ca2+ channels. SKF modulated HCN and LVA currents, suggesting that these channels are the target of D1R signaling to modulate visual signaling in these bipolar cells. Taken together, we found that dopamine modulates the temporal tuning of a subset of retinal bipolar cells. Consequently, we determined that dopamine plays a role in visual signal processing, which is similar to its role in signal decorrelation in the olfactory bulb.

Abstract Intensive agriculture has led to a reduction of overall biodiversity and ecosystem services such as pollination and biological control. To offset these economic losses, many farmers are planting native wildflowers to enhance flowering plant diversity and augment pollinator and other beneficial arthropod populations on their farms. In this study, we examined arthropod communities in Florida (USA) within wildflower plots and fallow control plots, which were primarily composed of grasses. Significantly more herbivorous insects, predatory arthropods, and pollinators were found within wildflower plots than in fallow control plots. We also implemented pollinator surveys at flowering plants. These surveys highlighted numerous plant–pollinator interactions within wildflower plots, supporting the idea that some native wildflower species are more attractive to pollinators than are others. Nevertheless, utilizing diverse flowering plants for wildflower plots may support a wide diversity of beneficial arthropod species, including native bees. Our results suggest that wildflower plantings in Florida can be a successful management tool to harbor increased overall plant and arthropod diversity (including native pollinators and other beneficial arthropods) within intensive agricultural areas.

Globally, coastal human population density is approximately three times than that of inland areas. Such development threatens the integrity of coastal ecosystems. Coastal dune systems contain unique sets of terrestrial invertebrates and native plants, and represent some of the last remaining areas of semi-natural habitats along the coasts. In our study, we monitored bee and flowering plant abundance and diversity within coastal dune systems located within protected lands and developed sites throughout South and Central Florida. Our aim was to assess the potential impacts dune degradation and development could have on these economically and ecologically important insects. A total of 5419 bees from 5 families and 56 taxa were captured using bowl traps. Halictidae accounted for 70% of all bees collected, followed by Apidae (28%), Megachilidae (2%), Andrenidae (0.1%) and Colletidae (0.07%). Both species richness and Shannon-Wiener diversity indices were higher in protected lands when compared with developed sites. A majority of the commonly collected bee species showed higher abundances in protected lands compared with developed sites. Protected lands also supported higher abundances of ground, wood, and tunnel-nesting bees when compared with developed sites. Bee species richness and Shannon-Wiener indices were lower in sites with greater percentages of development occurring within close proximity to the dune systems, and higher in sites with greater availability of dune coverage. We observed higher abundance and flowering plant species richness within protected lands when compared with developed sites; protected lands also supported more federally endangered/threatened or state protected plant species compared with developed sites. Overall, coastal dune systems are ecologically important bee sanctuaries and should be conserved to help sustain native bee communities and the flowering plants that occur within them. Keywords: native bees, Land use, Urban development, Coastal dunes, Diversity

The establishment of native wildflower plantings in Florida can benefit agricultural producers as well as native pollinators and other beneficial insects (predators and parasitoids). The plantings do this by: • providing forage and nesting sites for bees, butterflies, and other pollinators, • increasing wild bee numbers possibly across the farm, and • increasing natural enemies of insect pests (that also depend on forage and nesting sites). This document discusses choosing the right mix of native plant species to benefit many pollinator species, as well as proper site selection, planting practices, and weed control techniques. Wildflower plots should be practical to manage, maximize benefits to wildlife, and fit into the overall management practices of the property.

Green fluorescent protein (GFP) and its derivatives are broadly used in biomedical experiments for labeling particular cells or molecules. In the mouse retina, the light (∼500 nm) used to excite GFP can also lead to photoreceptor bleaching (peak ∼500 nm), which diminishes photoreceptor-mediated synaptic transmission in the retinal network. To overcome this problem, we investigated the use of infrared fluorescent protein (iRFP) as a marker since it is excited by light in the near-infrared range that would not damage the photoresponsiveness of the retina. Initially, we tested iRFP expression in human embryonic kidney 293 (HEK293) cells to confirm that conventional fluorescence microscopy can detect iRFP fluorescence. We next introduced the iRFP plasmid into adeno-associated virus 2 (AAV-2) and injected the resulting AAV-2 solution into the intraocular space. Retinal neurons were found to successfully express iRFP three weeks post-injection. Light-evoked responses in iRFP-marked cells were assessed using patch clamping, and light sensitivity was found to be similar in iRFP-expressing cells and non—iRFP-expressing cells, an indication that iRFP expression and detection do not affect retinal light responsiveness. Taken together, our results suggest iRFP can be a new tool for vision research, allowing for single-cell recordings from an iRFP marked neuron using conventional fluorescence microscopy.

Wildflower strip plantings in intensive agricultural systems have become a widespread tool for promoting pollination services and biological conservation because of their use by wasps and bees. Many of the trap-nesting wasps are important predators of common crop pests, and cavity-nesting bees that utilize trap-nests are important pollinators for native plants and many crops. The impact of wildflower strips on the nesting frequency of trap-nesting wasps or bees within localized areas has not been thoroughly investigated. Trap-nests made of bamboo reeds (Bambusa sp.) were placed adjacent to eight 0.1 ha wildflower plots and paired fallow areas (control plots) to determine if wildflower strips encourage the nesting of wasps and bees. From August 2014 to November 2015, occupied reeds were gathered and adults were collected as they emerged from the trap-nests. Treatment (wildflower or fallow plots) did not impact the number of occupied reeds or species richness of trap-nesting wasps using the occupied reeds. The wasps Pachodynerus erynnis, Euodynerus megaera, Parancistrocerus pedestris, and Isodontia spp. were the most common trap-nesting species collected. Less than 2% of the occupied reeds contained bees, and all were from the genus Megachile. The nesting wasp and bee species demonstrated preferences for reeds with certain inside diameters (IDs). The narrow range of ID preferences exhibited by each bee/wasp may provide opportunities to take advantage of their natural histories for biological control and/or pollination purposes.

The thermal hysteresis exhibited in plastic crystal compounds greatly reduces their cyclic efficiency, limiting their potential for replacing current environmentally harmful refrigerants. A mechanistic understanding of the origins of this hysteresis has yet to be established. Here, we systematically investigate the transformation kinetics of the model plastic crystal, neopentyl glycol (NPG), through microscopic and calorimetric techniques. We reveal an asymmetry between the forward (heating) and reverse (cooling) transitions. We also demonstrate that the forward transformation is rate-limited by the rate of growth of rotationally disordered domains. In contrast, the reverse transformation is rate-limited by the nucleation of the ordered crystal domain, demonstrated by the sharp exothermic peaks in calorimetry and rapid self-nucleation phenomena observed optically. This nucleation limitation is largely responsible for the large thermal hysteresis in NPG, which we observe to be as large as 16.7 °C for an approximately 10 mg sample cooled at 0.5 °C min−1. These findings demonstrate the underlying origin of the thermal hysteresis and introduce a direction to mitigate hysteresis in plastic crystal transformations. [ABSTRACT FROM AUTHOR]

Electrical transmission rights-of-way are ubiquitous and critical infrastructure across the landscape. Active vegetation management of these rights-of-way, a necessity to deliver electricity more safely, maintains these landscape features as stages of early successional habitat, a rarity in many regions, making these areas viable movement corridors for many taxa. The goals of this study were to (i) evaluate the effects of different electrical transmission landscape management practices on flowering plant and flower-visiting insect diversity parameters and (ii) generate conservation management inferences for these landscapes. In this study we tested the impact of three vegetation management levels across 18 electrical transmission sites. We evaluated the effects of treatment on bloom abundance and species richness as well as flower-visiting insect abundance and family richness. We identified 76541 flowers/inflorescences across 456 transects, including 188 species in 56 plant families. Additionally, we obtained data on 11361 flower-visitoring insects representing 33 families from 2376 pan trap sets. High vegetation management favored the reduction of coarse woody debris in the sites and harbored the highest level of abundance and richness of both floral resources and flower-visiting insects. We discuss that we can align social and ecological values of rights-of-way, ensuring their sustainability by applying regular and targeted integrated vegetation management. Thus, we can use rights-of-way landscapes not only as an effective management strategy for the delivery of essential human services, but also to provide conservation benefits for wild pollinators. [ABSTRACT FROM AUTHOR]

We present soft-template encapsulation of salt hydrate phase change materials (PCMs) using modified silica particles to both stabilize emulsions and serve as initiators for organocatalyzed photoredox ATRP. The resulting core–shell structures have high core loading and are robust to thermal cycling. Critically, this strategy eliminates the need for a reagent in the core phase, thus preserving purity, and offers the ability to tailor shell composition for desired applications. [ABSTRACT FROM AUTHOR]

Frozen shoulder is a common condition that causes pain and restriction of movement of the shoulder unrelated to secondary causes. It has three classic phases (freezing, frozen, and thawing), and is resolved in most cases within 1 to 2 years. Diagnosis is clinical based on global motion restriction and pain. Imaging plays an ancillary role to narrow the differential diagnosis. Physical therapy, nonsteroidal anti-inflammatories, and injection therapies are standard treatments, although none have been shown to alter the long-term course of the condition. Ultrasound guidance is recommended for injection-based therapy, although not required. Further study should focus on long-term outcomes and treatments that significantly alter the natural course of the disease. [ABSTRACT FROM AUTHOR]

Abstract Integral and interacting membrane proteins (IIMPs) constitute a vast family of biomolecules that perform essential functions in all forms of life. However, characterizing their interactions with lipid bilayers remains limited due to challenges in purifying and reconstituting IIMPs in vitro or labeling IIMPs without disrupting their function in vivo. Here, we report cell-free transcription-translation in a quartz crystal microbalance with dissipation (TXTL-QCMD) to dynamically characterize interactions between diverse IIMPs and membranes without protein purification or labeling. As part of TXTL-QCMD, IIMPs are synthesized using cell-free transcription-translation (TXTL), and their interactions with supported lipid bilayers are measured using a quartz crystal microbalance with dissipation (QCMD). TXTL-QCMD reconstitutes known IIMP-membrane dependencies, including specific association with prokaryotic or eukaryotic membranes, and the multiple-IIMP dynamical pattern-forming association of the E. coli division-coordinating proteins MinCDE. Applying TXTL-QCMD to the recently discovered Zorya anti-phage system that is unamenable to labeling, we discovered that ZorA and ZorB integrate within the lipids found at the poles of bacteria while ZorE diffuses freely on the non-pole membrane. These efforts establish the potential of TXTL-QCMD to broadly characterize the large diversity of IIMPs.

Magnetotelluric data were used to study the lithosphere structure of the Southern Oklahoma Aulacogen (SOA). Inversion of the data revealed two low resistivity anomalies beneath the SOA. The first is located in the depth range 0–90 km in the crust and upper lithospheric mantle. The second extends from a depth 100 km to the base of the lithospheric mantle and extends away from the SOA to the ends of the profile. The cause of low resistivity anomalies is discussed in relation to the tectonic evolution of the region and recent laboratory experiments on rock conductivity. The first anomaly is attributed to the combination of (a) water present in mantle minerals and (b) the formation of hydrous mineral phases by interactions between a plume and the lithosphere during rifting. Grain size reduction and fabric alignment from deformation during the Ancestral Rocky Mountain (ARM) orogeny may have also contributed to the low resistivity. This enrichment phase may have mechanically weakened the lithosphere and allowed deformation to occur during the ARM orogeny. The low resistivity of the deeper anomaly is attributed to a fluorine‐enriched phlogopite layer that is also coincident with an observed seismic mid‐lithosphere discontinuity (MLD). A lithosphere keel of mantle minerals enriched in water underlies this layer and may have formed by accretion of the plume head to the lower lithosphere after rifting, which also rethickened the lithosphere to its present‐day depths. The MLD may then reflect a melt layer along a paleo lithosphere‐asthenosphere boundary entombed during the accretion. Plain Language Summary: Earth's tectonic plates result from modification by past and present tectonic processes such as rifting and plumes. Processes that occurred in the past can be understood by present day studies of these processes that are active today. Geophysical imaging is a key part of these investigations as it provides information about subsurface structure. One method that is widely used is magnetotellurics (MT) which provides information about electrical resistivity. This parameter is sensitive to the presence of fluids and past metamorphism. The Southern Oklahoma Aulacogen is a failed rift located in the central USA. After the rifting occurred, compression formed the Ancestral Rocky Mountains (ARMs). This study uses MT data to understand how past tectonic events modified the North American Plate in this region. The results show that the lithosphere beneath the rift has a low electrical resistivity relative to the surrounding region. This suggests that metamorphism changed the composition of lithosphere and made it weaker. When later tectonic events caused compression, this weakening allowed the ARM to form. These results help us to understand how rifts and plumes modify plates at the present. Key Points: A 2‐D magnetotelluric model of the Southern Oklahoma Aulacogen in the USA is compared with regional geochemical and mineral physics dataAfter rifting, an enriched plume may have been accreted to the lithosphere and increased the lithospheric thickness to its current valueMetasomatism during rifting rheologically weakened the lithosphere, allowing deformation during the Ancestral Rocky Mountain orogeny [ABSTRACT FROM AUTHOR]

Abstract Point-of-care sensors, which are low-cost and user-friendly, play a crucial role in precision medicine by providing quick results for individuals. Here, we transform the conventional glucometer into a 4-hydroxytamoxifen therapeutic biosensor in which 4-hydroxytamoxifen modulates the electrical signal generated by glucose oxidation. To encode the 4-hydroxytamoxifen signal within glucose oxidation, we introduce the ligand-binding domain of estrogen receptor-alpha into pyrroloquinoline quinone-dependent glucose dehydrogenase by constructing and screening a comprehensive protein insertion library. In addition to obtaining 4-hydroxytamoxifen regulatable engineered proteins, these results unveil the significance of both secondary and quaternary protein structures in propagation of conformational signals. By constructing an effective bioelectrochemical interface, we detect 4-hydroxytamoxifen in human blood samples as changes in the electrical signal and use this to develop an electrochemical algorithm to decode the 4-hydroxytamoxifen signal from glucose. To meet the miniaturization and signal amplification requirements for point-of-care use, we harness power from glucose oxidation to create a self-powered sensor. We also amplify the 4-hydroxytamoxifen signal using an organic electrochemical transistor, resulting in milliampere-level signals. Our work demonstrates a broad interdisciplinary approach to create a biosensor that capitalizes on recent innovations in protein engineering, electrochemical sensing, and electrical engineering.

Previous literature suggests that Democratic candidates of color receive less support than white Democrats on Election Day. It has been suggested that this reduced support is due to voters' ideological perceptions of people of color being more liberal than whites, which translates into perceptions of candidates. However, these studies are frequently limited to white voters' perceptions of Democratic candidates of color, and the full relationship linking race/ethnicity, to ideological placement, to vote choice has rarely been tested. In the current study, we examine how both the race/ethnicity and party affiliation of Senate candidates shape perceptions of their ideology and vote choice among people of all race and ethnicities. Using the 2006–2018 Cooperative Congressional Election Study, we find support for our hypothesis that Black Democrats are generally perceived as more liberal than white Democrats. These perceptions have real consequences, resulting in fewer votes. Conversely, Black Republican candidates are perceived to be just as conservative—and Hispanic Republicans even more conservative—than white Republican candidates. Findings suggest that the link between race/ethnicity, perceptions of ideology, and electoral success vary according to the race/ethnicity and party of candidates. [ABSTRACT FROM AUTHOR]

Despite significant advances in the development and refinement of immunotherapies administered to combat cancer over the past decades, a number of barriers continue to limit their efficacy. One significant clinical barrier is the inability to mount initial immune responses towards the tumor. As dendritic cells are central initiators of immune responses in the body, the elucidation of mechanisms that can be therapeutically leveraged to enhance their functions to drive anti-tumor immune responses is urgently needed. Here, we report that the dietary sugar L-fucose can be used to enhance the immunostimulatory activity of dendritic cells (DCs). L-fucose polarizes immature myeloid cells towards specific DC subsets, specifically cDC1 and moDC subsets. In vitro, L-fucose treatment enhances antigen uptake and processing of DCs. Furthermore, our data suggests that L-fucose-treated DCs increase stimulation of T cell populations. Consistent with our functional assays, single-cell RNA sequencing of intratumoral DCs from melanoma- and breast tumor-bearing mice confirmed transcriptional regulation and antigen processing as pathways that are significantly altered by dietary L-fucose. Together, this study provides the first evidence of the ability of L-fucose to bolster DC functionality and provides rational to further investigate how L-fucose can be used to leverage DC function in order to enhance current immunotherapy.

Abstract Background Bystander administration of naloxone is a critical strategy to mitigate opioid overdose mortality. To ensure bystanders’ willingness to carry and administer naloxone in response to a suspected overdose, it is critical to select products for community distribution with the highest likelihood of being utilized. This study examines bystanders’ preference for and willingness to administer three naloxone products approved by the FDA for bystander use and identify product features driving preference. Methods The population was a convenience sample of individuals who attended the Kentucky State Fair, August 18–28, 2022, in Louisville, Kentucky. Participants (n = 503) watched a standardized overdose education and naloxone training video, rated their willingness to administer each of three products (i.e., higher-dose nasal spray, lower-dose nasal spray, intramuscular injection), selected a product to take home, and rated factors affecting choice. Results After training, 44.4% chose the higher-dose nasal spray, 30.1% chose the intramuscular injection, and 25.5% chose the lower-dose nasal spray. Factors most influencing choice on a 10-point Likert scale were ease of use (9 [7–10]), naloxone dose (8 [5–10]), and product familiarity (5 [5–9]). Conclusions Bystanders expressed high willingness to administer all studied formulations of naloxone products. Product choice preference varied as a function of product features. As the number and variety of available products continue to increase, continuous evaluation of formulation acceptability, in addition to including individuals with lived experience who are receiving and administering overdose reversal agents, is critical to support adoption and save lives.

The world is a book and those who do not travel only read one page. – St. Augustine

Research has found numerous differences between amateur and quality candidates in the realm of campaigns and elections, but little research has been conducted on the ideological differences between the two classes of candidates once they enter Congress. Using ideology scores and background data from members of the House since the 103rd Congress, I demonstrate that previously serving in an elected office exerts a moderating effect on Representatives' ideologies. These findings suggest that Representatives who had never served in elective government before joining Congress are less likely to compromise with the other party and thus more likely to add to Congressional polarisation. However, not all previous experience before joining Congress is equal. Previous experience serving at the local level, such as major or city council member, appears to have the greatest moderating effect on the ideology of members of the House. [ABSTRACT FROM AUTHOR]