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Abstract Nitric oxide (NO) emission via 5.3 µm wavelength plays dominant role in regulating the thermospheric temperature due to thermostat nature. The response of NO 5.3 mm emission to the negative pressure impulse during November 06–09, 2010 is studied by using Sounding of Atmosphere by Broadband Emission Radiometry (SABER) observations onboard the Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED) satellite and model simulations. The TIMED/SABER satellite observations demonstrate a significant enhancement in the high latitude region. The Open Geospace General Circulation Model (OpenGGCM), Weimer model simulations and Active Magnetosphere and Planetary Electrodynamics Response Experiment measurements exhibit intensification and equatorward expansion of the field-aligned-currents (FACs) post-negative pressure impulse period due to the expansion of the dayside magnetosphere. The enhanced FACs drive precipitation of low energy particle flux and Joule heating rate affecting whole magnetosphere–ionosphere–thermosphere system. Our study based on electric fields and conductivity derived from the EISCAT Troms$${\o }$$ $ø$radar and TIEGCM simulation suggests that the enhanced Joule heating rate and the particle precipitations prompt the increase in NO cooling emission. 

Abstract Flowering plant sexual reproduction relies on the communication between the pollen tube and synergid cells to induce pollen tube bursting. During this process, the MILDEW RESISTANCE LOCUS-O (MLO) protein NORTIA (NTA) is polarly trafficked from the Golgi, where it is inactive, to the filiform apparatus, where it is functional in synergids. MLOs were recently described as calcium channels and have been proposed to be negatively regulated through calmodulin (CaM) binding at a conserved C-terminal calmodulin-binding domain (CaMBD). To determine whether CaM binding is necessary for MLO function during pollen tube reception, C-terminal truncations and CaMBD point mutations were made in NTA. Point mutations were also generated in a constitutively filiform apparatus-localized chimeric NTA containing the MLO1 C-terminus. In this study, we demonstrate that mutating the MLO1 and NTA CaMBD reduces the ability for MLOs to function during pollen tube reception. This is in part due to altered subcellular localization of the CaMBD mutants in synergids. We showed that the CaMBD is not necessary for Golgi localization of MLOs, but is necessary for efficient trafficking and total protein accumulation at the filiform apparatus. Our results suggest an additional role for CaM binding as a regulator of MLO trafficking in addition to its previously proposed role as a negative regulator of MLO Ca2+ channel activity. 

Abstract Interplanetary (IP) shock is one of the most common phenomena that controls the shape and size of the magnetosphere. It affects the whole magnetosphere‐ionosphere‐thermosphere (MIT) system. We utilized the NO 5.3 m radiative emission, as observed by SABER (Sounding of the Atmosphere using Broadband Emission Radiometry) onboard NASA's TIMED (Thermosphere Ionosphere Mesosphere Energetics Dynamics) satellite, to investigate its response to fast forward shock during 26 January 2017. The high latitude NO emission exhibits a strong enhancement (three times with respect to pre‐event value) during IP shock within 5 hr of onset. We analyzed both the energy dissipation sources and subsequent chemical mechanisms. The Field‐Aligned‐Current observations from Active Magnetosphere and Planetary Response Experiment (AMPERE), EISCAT measurements of Pederson conductivity and the defense Meteorological Satellite Program (DMSP F18) calculated hemispheric power demonstrate a strong intensification. The low energy particle precipitation from DMSP F18 spacecraft shows an early enhancement for energy less than 1 keV. The particle flux of higher energy responds later which remained elevated for longer duration. The thermospheric density and temperature also experience significant variation during IP shock. The NO molecule and temperature displayed an early enhancement. NO density increased by an order of magnitude with respect to the pre‐event value. About 20 increase is noticed in the temperature variation. The atomic oxygen and atomic nitrogen illustrate an early depletion during IP event. The enhanced response of NO cooling to IP shock can be attributed to the combined effects of energy input and subsequent chemical mechanisms. 

Abstract Many root parasitic plants in the Orobanchaceae use host-derived strigolactones (SLs) as germination cues. This adaptation facilitates attachment to a host and is particularly important for the success of obligate parasitic weeds that cause substantial crop losses globally. Parasite seeds sense SLs through ‘divergent’ KARRIKIN INSENSITIVE2 (KAI2d)/HYPOSENSITIVE TO LIGHT α/β-hydrolases that have undergone substantial duplication and diversification in Orobanchaceae genomes. After germination, chemotropic growth of parasite roots toward a SL source also occurs in some species. We investigated which of the seven KAI2d genes found in a facultative hemiparasite, Phtheirospermum japonicum, may enable chemotropic responses to SLs. To do so, we developed a triple mutant Nbd14a,b kai2i line of Nicotiana benthamiana in which SL-induced degradation of SUPPRESSOR OF MORE AXILLARY GROWTH2 (MAX2) 1 (SMAX1), an immediate downstream target of KAI2 signaling, is disrupted. In combination with a transiently expressed, ratiometric reporter of SMAX1 protein abundance, this mutant forms a system for the functional analysis of parasite KAI2d proteins in a plant cellular context. Using this system, we unexpectedly found three PjKAI2d proteins that do not trigger SMAX1 degradation in the presence of SLs. Instead, these PjKAI2d proteins inhibit the perception of low SL concentrations by SL-responsive PjKAI2d in a dominant-negative manner that depends upon an active catalytic triad. Similar dominant-negative KAI2d paralogs were identified in an obligate hemiparasitic weed, Striga hermonthica. These proteins suggest a mechanism for attenuating SL signaling in parasites, which might be used to enhance the perception of shallow SL gradients during root growth toward a host or to restrict germination responses to specific SLs. 

An in-silico exercise was developed for a general chemistry laboratory course at St. Bonaventure University in which students examined potential energy surfaces, molecular orbital diagrams, and how bond orders and Lewis structures are connected. Pre- and post-assessment data suggests that, though students learned from the exercise, they are not connecting the concepts of bond order, Lewis structures, and resonance. There was a statistically significant improvement in the assessment scores before and after the laboratory experiment, and there was no statistical difference between the post-assessment and the follow-up assessment, which occurred after students completed the lab report 1 week after the initial experiment. The data suggest an improved understanding of computational chemistry concepts as well as improvement in the individual concepts of resonance, Lewis structures, and bond orders. However, an assessment question connecting these concepts did not show an improvement. An additional questionnaire was conducted to explore this discrepancy. This study indicates that more investigation is necessary with regard to students’ ability to make logical connections among bond orders, Lewis structures, and resonance. 

Abstract Cultivated meat production requires bioprocess optimization to achieve cell densities that are multiple orders of magnitude higher compared to conventional cell culture techniques. These processes must maximize resource efficiency and cost-effectiveness by attaining high cell growth productivity per unit of medium. Microcarriers, or carriers, are compatible with large-scale bioreactor use, and offer a large surface-area-to-volume ratio for the adhesion and proliferation of anchorage-dependent animal cells. An ongoing challenge persists in the efficient retrieval of cells from the carriers, with conflicting reports on the effectiveness of trypsinization and the need for additional optimization measures such as carrier sieving. To surmount this issue, edible carriers have been proposed, offering the advantage of integration into the final food product while providing opportunities for texture, flavor, and nutritional incorporation. Recently, a proof of concept (POC) utilizing inactivated mycelium biomass derived from edible filamentous fungus demonstrated its potential as a support structure for myoblasts. However, this POC relied on a model mammalian cell line combination with a single mycelium species, limiting realistic applicability to cultivated meat production. This study aims to advance the POC. We found that the species of fungi composing the carriers impacts C2C12 myoblast cell attachment—with carriers derived fromAspergillus oryzaepromoting the best proliferation. C2C12 myoblasts effectively differentiated on mycelium carriers when induced in myogenic differentiation media. Mycelium carriers also supported proliferation and differentiation of bovine satellite cells. These findings demonstrate the potential of edible mycelium carrier technology to be readily adapted in product development within the cultivated meat industry.