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Analysis of the ordinary mode (O‐mode) instability is performed to comprehend the nonthermal continuum (NTC) radiation near the plasmapause, taking into account the relativistic wave‐electron resonance effect. The energy source is the anisotropy in the velocity of the minority suprathermal electron population. Numerical solutions demonstrate that the O‐mode can be unstable with multiple narrow frequency bands located close to harmonics of the electron cyclotron frequency above the local electron plasma frequency. These waves have narrow beaming angle bands of nearly 90° $90{}^{\circ}$ relative to the ambient magnetic field. Our findings indicate that NTC radiation generated by this wave‐electron resonance instability near the plasmapause can propagate nearer to the magnetic equator with multiple harmonics, which is in agreement with a recent statistical study using Van Allen Probes. Key Points: The ordinary mode electron anisotropy instability is examined to comprehend the non‐thermal continuum radiation near the plasmapauseResonant ordinary modes are unstable over multiple narrow frequency and wavevector rangesNTC radiation generated by the instability near the plasmapause can propagate nearer to the magnetic equator [ABSTRACT FROM AUTHOR]

To understand the entry of the cool low‐latitude mantle ions into the tail plasma sheet near the flanks under persistent interplanetary magnetic field By, we evaluate the role of the cross‐field diffusive transport by kinetic Alfvén waves (KAWs) by investigating two events observed by multiscale (MMS) spacecraft. Around the separatrix between the open and closed field‐line regions, a two‐component mixing of hot plasma sheet ions of a few keV with cool mantle ions of a few hundred eV was observed, indicating transport across the separatrix. The waves observed between 0.01 and 10 Hz around the separatrix had characteristics consistent with those of KAWs. The consistency allowed us to estimate the wave vectors as a function of frequency by fitting KAW dispersion to the observations. Using the observed wave powers, plasma moments, and the estimated wave vectors, we computed the cross‐field diffusion rates associated with KAWs. The diffusion rates were found to be comparable to or larger than the Bohm diffusion rates during the intervals when the two‐component mixing was observed, indicating that the KAW diffusive transport can play a role in the entry of low‐latitude mantle ions into the plasma sheet. Key Points: We investigate cross‐field diffusive transport for the mixing of cold low‐latitude mantle ions and hot plasma sheet ions observed by MMSThe waves around the separatrix between the low‐latitude mantle and plasma sheet show the characteristics of kinetic Alfvén waves (KAWs)Estimated diffusive transport rates through KAWs are sufficiently large to cause the observed ion mixing [ABSTRACT FROM AUTHOR]

Genetic improvement of livestock productivity has resulted in greater production of metabolic heat and potentially greater susceptibility to heat stress. Various studies have demonstrated that there is genetic variability for heat tolerance and genetic selection for more heat tolerant individuals is possible. The rate of genetic progress tends to be greater when genomic information is incorporated into the analyses as more accurate breeding values can be obtained for young individuals. Therefore, this study aimed (1) to evaluate the predictive ability of genomic breeding values for heat tolerance based on routinely recorded traits, and (2) to investigate the genetic background of heat tolerance based on single‐step genome‐wide association studies for economically important traits related to body composition, growth and reproduction in Large White pigs. Pedigree information was available for 265,943 animals and genotypes for 8686 animals. The studied traits included ultrasound backfat thickness (BFT), ultrasound muscle depth (MDP), piglet weaning weight (WW), off‐test weight (OTW), interval between farrowing (IBF), total number of piglets born (TNB), number of piglets born alive (NBA), number of piglets born dead (NBD), number of piglets weaned (WN) and weaning‐to‐estrus interval (IWE). The number of phenotypic records ranged from 6059 (WN) to 172,984 (TNB). Single‐step genomic reaction norm predictions were used to calculate the genomic estimated breeding values for each individual. Predictions of breeding values for the validation population individuals were compared between datasets containing phenotypic records measured in the whole range of temperatures (WR) and datasets containing only phenotypic records measured when the weather station temperature was above 10°C (10C) or 15°C (15C), to evaluate the usefulness of these datasets that may better reflect the within‐barn temperature. The use of homogeneous or heterogeneous residual variance was found to be trait‐dependent, where homogeneous variance presented the best fit for MDP, BFT, OTW, TNB, NBA, WN and IBF, while the other traits (WW and IWE) had better fit with heterogeneous variance. The average prediction accuracy, dispersion and bias values considering all traits for WR were 0.36 ± 0.05, −0.07 ± 0.13 and 0.76 ± 0.10, respectively; for 10C were 0.39 ± 0.02, −0.05 ± 0.07 and 0.81 ± 0.05, respectively; and for 15C were 0.32 ± 0.05, −0.05 ± 0.11 and 0.84 ± 0.10, respectively. Based on the studied traits, using phenotypic records collected when the outside temperature (from public weather stations) was above 10°C provided better predictions for most of the traits. Forty‐three and 62 candidate genomic regions were associated with the intercept (overall performance level) and slope term (specific biological mechanisms related to environmental sensitivity), respectively. Our results contribute to improve genomic predictions using existing datasets and better understand the genetic background of heat tolerance in pigs. Furthermore, the genomic regions and candidate genes identified will contribute to future genomic studies and breeding applications. [ABSTRACT FROM AUTHOR]

Non‐invasive smart electronic‐free sampling capsules have revolutionized the exploration of microbiome‐disease interactions in inaccessible regions of the gastrointestinal (GI) tract. However, a significant impediment to the broader use of electronic‐free capsules is the challenge of reliably tracking and determining their in vivo location. Variability in patient motility introduces uncertainties in capsule position. Thus, there is a critical need for effective solutions that ensure traceability in microbiome studies employing such capsules. While tracking methods are explored in previous smart ingestible capsule designs, most have relied on RF, imaging, and radiation‐based techniques, limiting sampling volume, increasing costs, complicating design, and raising health concerns due to ionizing radiation exposure. To address these challenges, the design of an electronic‐free smart capsule is introduced that integrates a metal tracer for easy metal detection, serving as a reliable tracking mechanism. The capsule is housed in a 3D‐printed casing and includes a superabsorbent hydrogel serving as both a sampling medium and an actuator within the capsule. The capsule's targeted sampling of the GI tract is accomplished by covering the capsule's sampling port with a pH‐responsive coating. Optimal dimensions and material for the cylindrical shaped metal tracer on the capsule are determined through extensive optimizations, considering factors such as gastric flotation, corrosion resistance, read distance, and omnidirectional detectability. The results of these investigations reveal that a 12 mm stainless steel (SS 316L) cylinder offers the necessary detection and tracing capabilities with minimal toxicity and excellent corrosion resistance under relevant physiological conditions in the GI tract. Validation studies, both in vitro and in vivo, confirmed the capsule's trackability using a handheld metal detector. These findings are further validated by X‐ray imaging and CT scans, demonstrating the metal detector's ability to distinguish approximate GI tract regions and determine the time point of excretion. This innovative approach provides a reliable and cost‐effective solution for tracking electronic‐free smart capsules, enhancing their applicability in microbiome research for both human and animal studies. [ABSTRACT FROM AUTHOR]

The field of protein engineering has seen tremendous expansion in the last decade, with researchers developing novel proteins with specialised functionalities for a range of uses, from drug discovery to industrial biotechnology. The emergence of computational tools and high‐throughput screening technology has substantially sped up the process of protein engineering. However, much of the expertise required to engage in such projects is still concentrated in the hands of a few specialised individuals, including computational biologists and structural biochemists. The international Genetically Engineered Machine (iGEM) competition represents a platform for undergraduate students to innovate in synthetic biology. Yet, due to their complexity, arduous protein engineering projects are hindered by the resources available and strict timelines of the competition. The authors highlight how the 2022 iGEM Team, 'Sporadicate', set out to develop InFinity 1.0, a computational framework for increased accessibility to effective protein engineering, hoping to increase awareness and accessibility to novel in silico tools. [ABSTRACT FROM AUTHOR]

We examine coupling of fluctuations in the solar wind with electromagnetic ion cyclotron (EMIC) waves in the magnetosphere using an advanced full‐wave simulation code, Petra‐M. Dipole tilt dramatically affects the coupling process. While very little wave power can reach the inner magnetosphere without tilt effects, a tilted dipole field dramatically increases the efficiency of the coupling process. Solar wind fluctuations incident at high magnetic latitude effectively reaches the ground along the field line and mode‐convert to linearly polarized field‐aligned propagating waves at the Alfvén and IIH resonances. Therefore, solar wind compressions efficiently drive linearly polarized EMIC waves when the dipole angle is tilted toward or away from the Sun‐Earth direction. Plain Language Summary: The solar wind is emitted near the ecliptic planes, and solar wind pressure is one of the critical sources of wave activities in the Earth's magnetosphere. Since Earth's magnetic field is tilted to the ecliptic plane, compressed solar wind fluctuations can be incident over a wide range of magnetic latitudes depending on seasonal and diurnal variations. When the solar wind fluctuations reach Earth's magnetosphere, incoming wave energy can be linearly transferred to another wave mode, called a mode coupling. This paper examines the role of Earth's magnetic tilt on this mode coupling between solar wind fluctuation and electromagnetic ion cyclotron (EMIC) waves using an advanced full‐wave simulation code, Petra‐M. Without magnetic tilt, solar wind fluctuations incident at a low latitude are almost totally reflected. In contrast, solar wind fluctuations incident at high latitude can propagate efficiently into the inner magnetosphere and reach the ground. Compressional fluctuations can also be converted to linearly polarized, field‐aligned propagating waves. These results suggest that solar wind compressions can drive the linearly polarized EMIC waves and that the wave occurrence can have seasonal and diurnal dependence, which is expected to maximize at the maximum tilt of Earth's dipole into the Sun‐Earth direction. Key Points: Wave mode coupling of solar wind fluctuation to electromagnetic ion cyclotron (EMIC) waves is examined using an advanced 2D‐full wave simulation code, Petra‐MWhen the dipole magnetic field is tilted, compressional waves can reach the ground near the cusp region via mode conversionThe solar wind can drive linearly polarized EMIC waves via mode conversion more efficiently when the dipole field is tilted [ABSTRACT FROM AUTHOR]

The Juno spacecraft in a polar orbit around Jupiter has observed broadband electron energization signatures at high latitudes (Mauk et al., 2017, https://doi.org/10.1038/nature23648). We investigate the origin of this energization by simulating the propagation of dispersive Alfvén waves from the Io plasma torus to high latitudes. These waves may be triggered by mechanisms such as the moon‐magnetosphere interaction or inflows from radial transport. We build on the initial hybrid gyrofluid‐kinetic electron simulation of Damiano et al. (2019, https://doi.org/10.1029/2018gl081219) to further quantify electron energization by Alfvénic waves, and investigate this process as a local source mechanism for observed broadband superthermal electron populations. We find that the magnitude of energization increases with the wave amplitude, while decreasing the radial wavelength reduces the high‐latitude wave and particle energy flux. Over the examined range of initial conditions we successfully generate broadband electron populations consistent with Juno observations (Mauk et al., 2017, http://doi.org/10.1038/nature23648; Szalay et al., 2018, https://doi.org/10.1029/2018je005752), that contribute to both precipitating populations and those that form trans‐hemispheric beams. Our energized electron distributions are consistent with observed superthermal populations critical for the torus energy budget (Bagenal & Delamere, 2011, https://doi.org/10.1029/2010ja016294) and Io‐related auroral emission. Plain Language Summary: The Juno spacecraft, orbiting Jupiter, has observed energized electrons displaying a broad spectrum of energies close to the planet's poles. We seek an explanation for these energetic electrons by simulating Alfvén waves (transverse waves analogous to waves on a string) generated in Jupiter's magnetosphere. These waves carry energy originating from flow‐induced disturbances in the Io plasma torus to the planet's ionosphere, traveling along magnetic field lines. We find that close to the planet's ionosphere, Alfvén waves accelerate electrons in a manner consistent with the Juno observations. These energized particles then can move along the field line, either into the planet's atmosphere with key consequences for aurora, or down to the torus and beyond to produce the observed hot electron population required to explain the torus energy budget. We vary the amplitude of our initial Alfvén wave‐producing perturbations to show that a stronger wave results in stronger energization. Key Points: Simulations produce broadband bidirectional electron distributions on kiloelectronvolt scales via high‐latitude energization by inertial Alfvén wavesThe magnitude of high‐latitude broadband electron energization is directly proportional to the wave amplitudeThe bidirectional distributions may supply the superthermal electrons needed for the torus energy budget and Io‐related auroral emission [ABSTRACT FROM AUTHOR]

An empirical model of radiation belt relativistic electrons (μ = 560–875 MeV G−1 and I = 0.088–0.14 RE G0.5) with average energy ∼1.3 MeV is developed. The model inputs solar wind parameters (velocity, density, interplanetary magnetic field (IMF) |B|, Bz, and By), magnetospheric state parameters (SYM‐H and AL), and L*. The model outputs the radiation belt electron phase space density (PSD). The model is operational from L* = 3 to 6.5. The model is constructed with neural networks assisted by information theory. Information theory is used to select the most effective and relevant solar wind and magnetospheric input parameters plus their lag times based on their information transfer to the PSD. Based on the test set, the model prediction efficiency (PE) increases with increasing L*, ranging from −0.043 at L* = 3 to 0.76 at L* = 6.5. The model PE is near 0 at L* = 3–4 because at this L* range, the solar wind and magnetospheric parameters transfer little information to the PSD. Using solar wind observations at L1 and magnetospheric index (AL and SYM‐H) models solely driven by solar wind, the radiation belt model can be used to forecast PSD 30–60 min ahead. This baseline model can potentially complement a class of empirical models that input data from low earth orbit (LEO). Plain Language Summary: An empirical model of radiation belt relativistic electrons with an energy of 1–2 MeV is developed. The model inputs solar wind parameters, magnetospheric state parameters, and L*. L* gives a measure of radial distance from the center of the Earth with a unit of RE (radius of the Earth = 6,378 km). The model outputs the radiation belt electron phase space density (PSD). The model is operational from L* = 3 to L* 6.5. The model is constructed with an information theory informed neural networks. Information theory is used to select the relevant solar wind and magnetospheric parameters and their lag times based on the amount of information they provide to the radiation belt electrons. The model performance increases with increasing radial distance (L*) because at distances close to Earth (L* = 3–4), the solar wind and magnetospheric parameters provide little information about the radiation belt electron PSD. The model can be used to forecast radiation belt PSD 30–60 min ahead. Key Points: An empirical model to predict state of radiation belt relativistic electrons is developedThe model prediction efficiency increases with increasing L* with a PE > 0.6 at L* > 5The model can potentially complement a class of empirical models that input observations from low earth orbit [ABSTRACT FROM AUTHOR]

In the present study, we explore the observational characteristics of Electromagnetic Ion Cyclotron (EMIC) wave propagation from the source region to the ground. We use magnetometers aboard Geostationary Operational Environment Satellite (GOES) 13, the geosynchronous orbit satellite at 75°W, and at Sanikiluaq ground station (SNK, 79.14°W and 56.32°N in geographic coordinates, and L ∼ 6.0 in a dipole magnetic field) which is located in northern Canada. Using these magnetically conjugate observatories, simultaneous EMIC wave observations are carried out. We found a total of 295 coincident and 248 non‐coincident EMIC wave events between GOES 13 and the SNK station. Our statistical analysis reveals that the coincident events are predominantly observed on the dayside. The wave normal angles are slightly higher for the non‐coincident events than for coincident events. However, the coincidence of the waves is mostly governed by the intensity and duration of the wave. This is confirmed by the geomagnetic environment which shows higher auroral electrojet (AE) and Kp indices for the coincident events. We also found that some events show high‐frequency (f > 0.4 Hz) wave filtering. The statistics of the high‐frequency filtered and non‐filtered wave events show that there are clear magnetic local time (MLT) and F10.7 index differences between the two groups, as well as in ionospheric electron density measurements. In addition, we also found differences in the wave properties which possibly indicate that the propagation in the magnetosphere also plays an important role in the wave filtering. Key Points: Coincidence of the Electromagnetic Ion Cyclotron wave observation is studied using conjugate space [Geostationary Operational Environment Satellite (GOES) 13] and ground (SNK ground magnetometer) observationsThe Coincidence of the waves is primarily dominated by wave power and durationThe high‐frequency wave filtering is complicated by both magnetospheric and ionospheric wave propagation [ABSTRACT FROM AUTHOR]

A sustained state of methionine restriction (MR) dramatically extends the healthspan of several model organisms. For example, continuously methionine‐restricted rodents have less age‐related pathology and are up to 45% longer‐lived than controls. Promisingly, MR is feasible for humans, and studies have suggested that methionine‐restricted individuals may receive similar benefits to rodents. However, long‐term adherence to a methionine‐restricted diet is likely to be challenging for many individuals. Prompted by this, and the fact that intermittent variants of other healthspan‐extending interventions (i.e., intermittent fasting and the cyclic ketogenic diet) are just as effective, if not more, than their continuous counterparts, we hypothesized that an intermittent form of MR might produce similar healthspan benefits to continuous MR. Accordingly, we developed two increasingly stringent forms of intermittent MR (IMR) and assessed whether mice maintained on these diets demonstrate the beneficial metabolic changes typically observed for continuous MR. To the best of our knowledge, we show for the first time that IMR produces similar beneficial metabolic effects to continuous MR, including improved glucose homeostasis and protection against diet‐induced obesity and hepatosteatosis. In addition, like continuous MR, IMR confers beneficial changes in the plasma levels of the hormones IGF‐1, FGF‐21, leptin, and adiponectin. Together, our findings demonstrate that the more practicable intermittent form of MR produces similar healthspan benefits to continuous MR, and thus may represent a more appealing alternative to the classical intervention. [ABSTRACT FROM AUTHOR]

Many solar wind parameters correlate with one another, which complicates the causal‐effect studies of solar wind driving of the magnetosphere. Conditional mutual information (CMI) is used to untangle and isolate the effect of individual solar wind and magnetospheric drivers of the radiation belt electrons. The solar wind density (nsw) negatively correlates with electron phase space density (PSD; average energy ∼1.6 MeV) with time lag (τ) = 15 hr. The effect of nsw has been attributed to magnetopause shadowing or other loss mechanisms, but when the effect of solar wind velocity (Vsw) is removed, τ shifts to 7–11 hr, which is a more accurate time scale for this process. The peak correlation between Vsw and PSD shifts from τ = 30–50 to 44–56 hr, when the effect of nsw is removed. This suggests that the time scale for electron acceleration to 1–2 MeV is about 44–56 hr following Vsw enhancements. The effect of nsw is significant only at L* = 4.5–6 (L* > 6 is highly variable), whereas the effect of Vsw is significant only at L* = 3.5–6.5. The peak response of PSD to Vsw is the shortest and most significant at L* = 4.5–5.5. As time progresses, the peak response broadens and shifts to higher τ at higher and lower L*, consistent with local acceleration at L* = 4.5–5.5 followed by outward and inward diffusion. The outward radial diffusion time scale at L* = 5–6 is ∼40 hr per RE. Plain Language Summary: Many solar wind parameters correlate with one another, which complicates the causal‐effect studies of solar wind driving of the magnetosphere. We use conditional mutual information, which is part of information theory, to untangle and isolate the effect of individual solar wind and magnetospheric drivers of the radiation belt electrons. For example, the solar wind density negatively correlates with electron phase space density (PSD) (average energy ∼1.6 MeV) with the response time lag of 15 hr. This has been attributed to the electron loss process such as magnetopause shadowing. The time lag suggests the time scale for this process is 15 hr. However, when the effect of solar wind velocity is removed, the time lag is 7–11 hr, which is a more accurate time scale for this process. As another example, the time lag of the correlation between solar wind velocity and PSD shifts from 30 to 50 to 44–56 hr, when the effect of solar wind density is removed. This suggests that the time scale for electron acceleration to 1–2 MeV is about 44–56 hr following the solar wind velocity enhancements. We also show that the effects of solar wind velocity and density have dependence on radial distance. Key Points: The effect of nsw on radiation belt electrons is significant only at L* = 4.5–6 and not significant at L* < 4.5The effect of Vsw on radiation belt electrons is significant at L* = 3.5–6.5 and not significant at L* < 3.5The radiation belt electron response time lag to Vsw suggests local acceleration at L* = 4–5.5 followed by outward and inward diffusion [ABSTRACT FROM AUTHOR]

Many processes throughout the heliosphere such as flares, coronal mass ejections (CMEs), storms and substorms have abrupt onsets. The waiting time between these onsets provides key insights as to the underlying dynamical processes. We explore the tail of these waiting time distributions (WTDs) in the context of random processes driven by the solar magnetic activity cycle, which we approximate by a sinusoidal driver. Analytically, we find that the distribution of large waiting times of such a process approaches a power law slope of −2.5, which is primarily controlled by the conditions when the driving is minimum. We find that the asymptotic behavior of WTDs of solar flares, CMEs, geomagnetic storms, and substorms exhibit power laws that are in reasonable agreement with a sinusoidally driven nonstationary Poisson process. However, the WTD of substorms during solar minimum may be more consistent with prolonged periods of weak driving followed by abrupt increase in the rate. Plain Language Summary: Many events in the solar system are driven by the magnetic activity cycle of the sun. In this study, we show that for cyclical driving of a Poisson process, the probability of the time between events satisfies a power law of −2.5 when the time between events is large. We show that this power law reasonably describes the distribution of waiting times for solar flares, CMEs, and storms at long waiting time. Additionally, we show that the distribution of long waiting times is primarily determined by the minimum of the driving process. Key Points: Many heliospheric waiting time distributions are consistent with sinusoidal driving of a random processMinima in the driving process determine the tail of the waiting time distributionThe power law of the waiting time distribution is asymptotic to −2.5 for sinusoidal driving [ABSTRACT FROM AUTHOR]

Aims: Increasing the diversity of the biomedical sciences workforce is a national priority. Having a mentor, and more crucially, a personal network of mentors, improves the likelihood that an individual will pursue an advanced degree and career in the biomedical sciences. The chief mission of the National Research Mentoring Network (NRMN) is to reduce racial and ethnic disparities in the biosciences workforce through the mentoring of historically underrepresented individuals. Methods: To address this need, we created MyNRMN, an online mentoring platform that connects mentors and mentees nationwide. The platform enables multiple forms of mentoring and recommends connections to mentees that will help them build their personal networks. Results: The MyNRMN online platform has registered more than 13,500 active mentors and mentees across all 50 states and from more than 2100 institutions. Black and Hispanic mentees are highly represented. Discussion: MyNRMN has expanded opportunities for mentorship in the biomedical sciences, particularly among those not from a culture or institution that historically supports mentorship. The platform's robust search and recommendation capabilities and graph database technology enable members to grow their personal network of mentors. Conclusion: The MyNRMN online platform has proven successful in connecting mentees and mentors nationwide, expanding the pipeline in biomedical science careers to attract a more diverse workforce. [ABSTRACT FROM AUTHOR]

All neurodegenerative diseases feature aggregates, which usually contain disease‐specific diagnostic proteins; non‐protein constituents, however, have rarely been explored. Aggregates from SY5Y‐APPSw neuroblastoma, a cell model of familial Alzheimer's disease, were crosslinked and sequences of linked peptides identified. We constructed a normalized "contactome" comprising 11 subnetworks, centered on 24 high‐connectivity hubs. Remarkably, all 24 are nucleic acid‐binding proteins. This led us to isolate and sequence RNA and DNA from Alzheimer's and control aggregates. RNA fragments were mapped to the human genome by RNA‐seq and DNA by ChIP‐seq. Nearly all aggregate RNA sequences mapped to specific genes, whereas DNA fragments were predominantly intergenic. These nucleic acid mappings are all significantly nonrandom, making an artifactual origin extremely unlikely. RNA (mostly cytoplasmic) exceeded DNA (chiefly nuclear) by twofold to fivefold. RNA fragments recovered from AD tissue were ~1.5‐to 2.5‐fold more abundant than those recovered from control tissue, similar to the increase in protein. Aggregate abundances of specific RNA sequences were strikingly differential between cultured SY5Y‐APPSw glioblastoma cells expressing APOE3 vs. APOE4, consistent with APOE4 competition for E‐box/CLEAR motifs. We identified many G‐quadruplex and viral sequences within RNA and DNA of aggregates, suggesting that sequestration of viral genomes may have driven the evolution of disordered nucleic acid‐binding proteins. After RNA‐interference knockdown of the translational‐procession factor EEF2 to suppress translation in SY5Y‐APPSw cells, the RNA content of aggregates declined by >90%, while reducing protein content by only 30% and altering DNA content by ≤10%. This implies that cotranslational misfolding of nascent proteins may ensnare polysomes into aggregates, accounting for most of their RNA content. [ABSTRACT FROM AUTHOR]

Auroral bright spots have been observed at Earth, Jupiter, and Saturn in regions that map to the magnetopause boundary layer. It has been suggested that the bright spots are associated with the Kelvin-Helmholtz (KH) instability. We utilize a quasistatic magnetosphere-ionosphere coupling model driven by a vortex in the boundary layer to determine how the field-aligned current structure depends on ionospheric and boundary layer parameters. We compare vortex induced currents with shear-flow induced currents. We find that the strength of the maximum currents are comparable, but the structure is significantly different. For a vortex, the current and electron precipitation maximize when the vortex size mapped to the ionosphere is approximately 1.5L, where L = ... is the auroral scale length, ΣP is the Pedersen conductivity, and κ is the Knight parameter. For a vortex, the current width provides a direct measure of the size, Δ, of the boundary layer structure, while the current width of shear-flow aurora is generally determined by the larger of Δ or L. For comparison with observations, an event is considered where auroral bright spots in the ionosphere are detected by DMSP SSUSI FUV when KH structures are observed on the dusk flank by THEMIS. [ABSTRACT FROM AUTHOR]

We have used the Auburn Global Hybrid Code in 3‐D to study the generation, dynamics, and global structure of kinetic Alfvén waves (KAWs) from the magnetotail to the ionosphere. Our results show that KAWs are generated in magnetic reconnection in the plasma sheet, located around fast flows, and carrying transverse electromagnetic perturbations, parallel Poynting fluxes, parallel currents, and parallel electric field. Overall, shear Alfvénic turbulent spectrum is found in the plasma sheet. The KAWs are shear Alfvén waves possessing short perpendicular wavelength with k⊥ρi∼1, where k⊥ is the perpendicular wave number and ρi the ion Larmor radius. The KAWs are identified by their dispersion relation and polarizations. The structures of these KAWs embedded in the plasma sheet are also revealed by placing a virtual satellite in the tail. In order to understand whether the Poynting fluxes carried by the shear Alfvén waves/KAWs in the plasma sheet can be carried directly along field lines to the ionosphere, we have tracked the wave propagation from the plasma sheet to the ionosphere. It is found that in front of the flow‐braking region, the structure and strength of the shear Alfvén waves are significantly altered due to interaction with the dipole‐like field, mainly by the flow shear associated with the azimuthal convection. Also in front of the dipole‐like field region, ion kinetic effects (Hall effects) lead to the generation of additional pairs of KAWs. As such, the generation and transport of the shear Alfvén waves/KAWs to the ionosphere are illustrated for the first time in a comprehensive manner on the global scale. Key Points: Global evolution of kinetic Alfvén waves (KAWs) from the magnetotail to the ionosphere is analyzed using a 3‐D global hybrid simulationKAWs are shown to be generated in the plasma sheet by reconnection and in the flow‐braking region due to ion inertial effectDipole‐like field region alters the structure and strength of the shear Alfvén waves that propagate to the ionosphere [ABSTRACT FROM AUTHOR]

While the concept of aggregating and controlling renewable distributed energy resources (DERs) to provide grid services is not new, increasing policy support of DER market participation has driven research and development in algorithms to pool DERs for economically viable market participation. Sandia National Laboratories recently undertook a 3 year research programme to create the components of a real-world virtual power plant (VPP) that can simultaneously participate in multiple markets. The authors' research extends current state-of-the-art rolling horizon control through the application of stochastic programming with risk aversion at various time resolutions. Their rolling horizon control consists of day-ahead optimisation to produce an hourly aggregate schedule for the VPP operator and sub-hourly optimisation for the real-time dispatch of each VPP subresource. Both optimisation routines leverage a two-stage stochastic programme with risk aversion and integrate the most up-to-date forecasts to generate probabilistic scenarios in real operating time. Their results demonstrate the benefits to the VPP operator of constructing a stochastic solution regardless of the weather. In more extreme weather, applying risk optimisation strategies can dramatically increase the financial viability of the VPP. The methodologies presented here can be further tailored for optimal control of any VPP asset fleet and its operational requirements. [ABSTRACT FROM AUTHOR]

We discuss a role of the electron inertial effect on linearly polarized electromagnetic ion cyclotron (EMIC) waves at Earth. The linearly polarized EMIC waves have been previously suggested to be generated via mode conversion from the fast compressional wave at the ion‐ion hybrid (IIH) resonance. When the electron inertial effects are neglected, the wave normal angle of the mode‐converted IIH waves is 90° because the wave vector perpendicular to the magnetic field becomes infinite at the IIH resonance. When the electron inertial effect is considered, the mode‐converted IIH waves can propagate across the magnetic field lines, and the wavelength perpendicular to the magnetic field approaches the electron inertial length scale near the Buchsbaum resonance. These waves are referred to as electron inertial waves. Due to the electron inertial effect, the perpendicular wave number to the ambient magnetic field near the IIH resonance remains finite, and the wave normal angle is less than 90°. The wave normal angle where the maximum absorption occurs in a dipole magnetic field is 30–80°, which is consistent with the observed values near the magnetic equator. Therefore, the numerical results suggest that the linearly polarized EMIC wave generated via mode conversion near the IIH resonance can be detected in between the Buchsbaum and the IIH resonance frequencies, and these waves can have normal angle less than 90°. Key Points: Mode‐converted ion‐ion hybrid waves can propagate toward the Buchsbaum resonance due to the electron inertial effectsElectron inertial effects allow the mode‐converted ion‐ion hybrid waves have medium normal angle less than 90°Linearly polarized EMIC waves generated via mode conversion can have relatively small normal angle between 30 and 80° [ABSTRACT FROM AUTHOR]

Abstract: The goal of the aging field is to develop novel therapeutic interventions that extend human health span and reduce the burden of age‐related disease. While organismal aging is a complex, multifactorial process, a popular theory is that cellular aging is a significant contributor to the progressive decline inherent to all multicellular organisms. To explore the molecular determinants that drive cellular aging, as well as how to retard them, researchers have utilized the highly genetically tractable budding yeast Saccharomyces cerevisiae. Indeed, every intervention known to extend both cellular and organismal health span was identified in yeast, underlining the power of this approach. Importantly, a growing body of work has implicated the process of autophagy as playing a critical role in the delay of aging. This review summarizes recent reports that have identified a role for autophagy, or autophagy factors in the extension of yeast life span. These studies demonstrate (1) that yeast remains an invaluable tool for the identification and characterization of conserved mechanisms that promote cellular longevity and are likely to be relevant to humans, and (2) that the process of autophagy has been implicated in nearly all known longevity‐promoting manipulations and thus represents an ideal target for interventions aimed at improving human health span. [ABSTRACT FROM AUTHOR]

Habitat disturbance from development, resource extraction, off-road vehicle use, and energy development ranks highly among threats to desert systems worldwide. In the Mojave Desert, United States, these disturbances have promoted the establishment of nonnative plants, so that native grasses and forbs are now intermixed with, or have been replaced by invasive, nonnative Mediterranean grasses. This shift in plant composition has altered food availability for Mojave Desert tortoises (Gopherus agassizii), a federally listed species. We hypothesized that this change in forage would negatively influence the physiological ecology, immune competence, and health of neonatal and yearling tortoises. To test this, we monitored the effects of diet on growth, body condition, immunological responses (measured by gene transcription), and survival for 100 captive Mojave tortoises. Tortoises were assigned to one of five diets: native forbs, native grass, invasive grass, and native forbs combined with either the native or invasive grass. Tortoises eating native forbs had better body condition and immune functions, grew more, and had higher survival rates (>95%) than tortoises consuming any other diet. At the end of the experiment, 32% of individuals fed only native grass and 37% fed only invasive grass were found dead or removed from the experiment due to poor body conditions. In contrast, all tortoises fed either the native forb or combined native forb and native grass diets survived and were in good condition. Health and body condition quickly declined for tortoises fed only the native grass (Festuca octoflora) or invasive grass (Bromus rubens) with notable loss of fat and muscle mass and increased muscular atrophy. Bromus rubens seeds were found embedded in the oral mucosa and tongue in most individuals eating that diet, which led to mucosal inflammation. Genes indicative of physiological, immune, and metabolic functions were transcribed at lower levels for individuals fed B. rubens, indicating potential greater susceptibility to disease or other health-related problems. This study highlights the negative indirect effects of invasive grasses, such as red brome, in desert ecosystems, and provides definitive evidence of a larger negative consequence to health, survival, and ultimately population recruitment for Mojave Desert tortoises than previously understood. [ABSTRACT FROM AUTHOR]

The increasing pressure for network operators to meet distribution network power quality standards with increasing peak loads, renewable energy targets, and advances in automated distributed power electronics and communications is forcing policy-makers to understand new means to distribute costs and benefits within electricity markets. Discussions surrounding how distributed generation (DG) exhibits active voltage regulation and power factor/reactive power control and other power quality capabilities are complicated by uncertainties of baseline local distribution network power quality and to whom and how costs and benefits of improved electricity infrastructure will be allocated. DG providing ancillary services that dynamically respond to the network characteristics could lead to major network improvements. With proper market structures renewable energy systems could greatly improve power quality on distribution systems with nearly no additional cost to the grid operators. Renewable DG does have variability challenges, though this issue can be overcome with energy storage, forecasting, and advanced inverter functionality. This paper presents real data from a large-scale grid-connected PV array with large-scale storage and explores effective mitigation measures for PV system variability. We discuss useful inverter technical knowledge for policy-makers to mitigate ongoing inflation of electricity network tariff components by new DG interconnection requirements or electricity markets which value power quality and control. [ABSTRACT FROM AUTHOR]

Unmitigated arc-faults present fire dangers, shock hazards, and cause system downtime in photovoltaic (PV) systems. The 2011 National Electrical Code® added section 690.11 to require a listed arc-fault protection device on new PV systems. Underwriters Laboratories created the outline of investigation for PV DC arc-fault circuit protection, UL 1699B, for certifying arc-fault circuit interrupters (AFCIs) for arc suppression. Unfortunately, little is known about appropriate trip times for arc-faults generated at different locations in the PV system, with different electrode and polymer encapsulant geometries and materials. In this investigation, a plasma model was developed, which determines fire danger with UL 1699B-listed AFCIs and consequences of arc-fault discharges sustained beyond UL 1699B trip time requirements. This model predicts temperatures for varying system configurations and was validated by 100 and 300 W arc-faults experiments where combustion times and temperatures were measured. This investigation then extrapolated burn characteristics using this model to predict polymer ignition times for exposure to arc-power levels between 100 and 1200 W. The numerical results indicate AFCI maximum trip times required by UL 1699B are sufficient to suppress 100-1200 W arc-faults prior to fire initiation. Optical emission spectroscopy and thermochemical decomposition analysis were also conducted to assess spectral and chemical degradation of the polymer sheath. Published 2014. This article has been contributed to by US Government employees and their work is in the public domain in the USA. [ABSTRACT FROM AUTHOR]

Proper insulin homeostasis appears critical for adapting to and surviving a heat load. Further, heat stress ( HS) induces phenotypic changes in livestock that suggest an increase in insulin action. The current study objective was to evaluate the effects of HS on whole-body insulin sensitivity. Female pigs (57 ± 4 kg body weight) were subjected to two experimental periods. During period 1, all pigs remained in thermoneutral conditions ( TN; 21°C) and were fed ad libitum. During period 2, pigs were exposed to: (i) constant HS conditions (32°C) and fed ad libitum ( n = 6), or (ii) TN conditions and pair-fed ( PFTN; n = 6) to eliminate the confounding effects of dissimilar feed intake. A hyperinsulinemic euglycemic clamp ( HEC) was conducted on d3 of both periods; and skeletal muscle and adipose tissue biopsies were collected prior to and after an insulin tolerance test ( ITT) on d5 of period 2. During the HEC, insulin infusion increased circulating insulin and decreased plasma C-peptide and nonesterified fatty acids, similarly between treatments. From period 1 to 2, the rate of glucose infusion in response to the HEC remained similar in HS pigs while it decreased (36%) in PFTN controls. Prior to the ITT, HS increased (41%) skeletal muscle insulin receptor substrate-1 protein abundance, but did not affect protein kinase B or their phosphorylated forms. In adipose tissue, HS did not alter any of the basal or stimulated measured insulin signaling markers. In summary, HS increases whole-body insulin-stimulated glucose uptake. [ABSTRACT FROM AUTHOR]

Heat stress ( HS) jeopardizes human and animal health and reduces animal agriculture productivity; however, its pathophysiology is not well understood. Study objectives were to evaluate the direct effects of HS on carbohydrate and lipid metabolism. Female pigs (57 ± 5 kg body weight) were subjected to two experimental periods. During period 1, all pigs remained in thermoneutral conditions ( TN; 20°C) and were ad libitum fed. During period 2, pigs were exposed to: (1) constant HS conditions (32°C) and fed ad libitum ( n = 7), or (2) TN conditions and pair-fed ( PFTN; n = 10) to minimize the confounding effects of dissimilar feed intake. All pigs received an intravenous glucose tolerance test ( GTT) and an epinephrine challenge ( EC) in period 1, and during the early and late phases of period 2. After 8 days of environmental exposure, all pigs were killed and tissue samples were collected. Despite a similar reduction in feed intake (39%), HS pigs tended to have decreased circulating nonesterified fatty acids ( NEFA; 20%) and a blunted NEFA response (71%) to the EC compared to PFTN pigs. During early exposure, HS increased basal circulating C-peptide (55%) and decreased the insulinogenic index (45%) in response to the GTT. Heat-stressed pigs had a reduced T3 to T4 ratio (56%) and hepatic 5′-deiodinase activity (58%). After 8 days, HS decreased or tended to decrease the expression of genes involved in oxidative phosphorylation in liver and skeletal muscle, and ATGL in adipose tissue. In summary, HS markedly alters both lipid and carbohydrate metabolism independently of nutrient intake. [ABSTRACT FROM AUTHOR]

ABSTRACT A multistaged geophysical methodology was recently used at site 15Ck10, a state-protected Middle Woodland period Adena (500 bce to ce 250) conical burial mound in Central Kentucky, USA. Data from this research are used to develop anthropological interpretations on the nature of burial mound construction and regional interaction between separate mortuary traditions in Kentucky. Methods utilized in this research include magnetic gradiometry, electromagnetic induction, ground-penetrating radar, electrical resistivity tomography and downhole magnetic susceptibility. Together, these methods helped identify a circular ditch-and-embankment earthwork enclosing the burial mound, as well as possible off-mound activity areas commonly reported in the Adena literature. Within the mound, multiple anomalies were discovered that are consistent with hypothesized geophysical responses of mound stages and funerary features. A review of burial mounds excavated by the University of Kentucky during the depression-era work relief programmes (i.e. the Works Progress Administration - WPA) of the 1930s and early 1940s provide a vehicle with which to interpret these features. Comparisons of our data with length and width dimensions of known mortuary facilities documented in WPA excavations suggest that two distinct burial types were used at 15Ck10. These data are used to build a comprehensive site interpretation and create a relative dating context for the site. We use the site-level model to evaluate regional interaction on Kentucky's Middle Woodland social landscape. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Metal catalyst free carbon nanotube (MCFCNT) whiskers were first used as an electrode modification material on a gold electrode surface for zinc voltammetric measurements. A composite film of Nafion and MCFCNT whiskers was applied to a gold electrode surface to form a mechanically stable sensor. The sensor was then used for zinc detection in both acetate buffer solution and extracted bovine serum solution. A limit of detection of 53 nM was achieved for a 120 s deposition time. The zinc in bovine serum was extracted via a double extraction procedure using dithizone in chloroform as a zinc chelating ligand. The modified electrode was found to be both reliable and sensitive for zinc measurements in both matrices. [ABSTRACT FROM AUTHOR]

A novel catalyst free carbon nanotube (CNT) electrode was fabricated by a Carbo Thermo Carbide Conversion (CTCC) method. The morphology and nanostructure of the CNT electrodes were characterized by transmission electron microscopy (TEM) and Raman spectroscopy. Electrochemical characterization using potassium ferricyanide, ferroin and catechol shows these CNTs have higher current capacity, faster electron transfer rate and larger microscopic surface area than glassy carbon (GC) electrode. [ABSTRACT FROM AUTHOR]

Anodic stripping voltammetry (ASV) and cathodic stripping voltammetry (CSV) were used to determine Mn concentration using metal catalyst free carbon nanotube (MCFCNT) electrodes and square wave stripping voltammetry (SWSV). The MCFCNTs are synthesized using a Carbo Thermal Carbide Conversion method which results in a material that does not contain residual transition metals. Detection limits of 120 nM and 93 nM were achieved for ASV and CSV, respectively, with a deposition time of 60 s. CSV was found to be better than ASV in Mn detection in many aspects, such as limit of detection and sensitivity. The CSV method was used in pond water matrix addition measurements. [ABSTRACT FROM AUTHOR]