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Particles are accelerated to very high, non-thermal energies during explosive energy-release phenomena in space, solar, and astrophysical plasma environments. While it has been established that magnetic reconnection plays an important role in the dynamics of Earth's magnetosphere, it remains unclear how magnetic reconnection can further explain particle acceleration to non-thermal energies. Here we review recent progress in our understanding of particle acceleration by magnetic reconnection in Earth's magnetosphere. With improved resolutions, recent spacecraft missions have enabled detailed studies of particle acceleration at various structures such as the diffusion region, separatrix, jets, magnetic islands (flux ropes), and dipolarization front. With the guiding-center approximation of particle motion, many studies have discussed the relative importance of the parallel electric field as well as the Fermi and betatron effects. However, in order to fully understand the particle acceleration mechanism and further compare with particle acceleration in solar and astrophysical plasma environments, there is a need for further investigation of, for example, energy partition and the precise role of turbulence., Submitted to Space Science Reviews; Revised on July 21, 2023

Using observations from the Solar Dynamics Observatory's Atmosphere Imaging Assembly and the Ramaty High Energy Solar Spectroscopic Imager, we present novel measurements of the shear of post-reconnection flare loops (PRFLs) in SOL20141218T21:40 and study its evolution with respect to magnetic reconnection and flare emission. Two quasi-parallel ribbons form adjacent to the magnetic polarity inversion line (PIL), spreading in time first parallel to the PIL and then mostly in a perpendicular direction. We measure magnetic reconnection rate from the ribbon evolution, and also the shear angle of a large number of PRFLs observed in extreme ultraviolet passbands ($\lesssim$1 MK). For the first time, the shear angle measurements are conducted using several complementary techniques allowing for a cross-validation of the results. In this flare, the total reconnection rate is much enhanced before a sharp increase of the hard X-ray emission, and the median shear decreases from 60$^\circ$-70$^\circ$ to 20$^\circ$, on a time scale of ten minutes. We find a correlation between the shear-modulated total reconnection rate and the non-thermal electron flux. These results confirm the strong-to-weak shear evolution suggested in previous observational studies and reproduced in numerical models, and also confirm that, in this flare, reconnection is not an efficient producer of energetic non-thermal electrons during the first ten minutes when the strongly sheared PRFLs are formed. We conclude that an intermediate shear angle, $\le 40^\circ$, is needed for efficient particle acceleration via reconnection, and we propose a theoretical interpretation., 19 pages, 10 figures

The fast solar wind that fills the heliosphere originates from deep within regions of open magnetic field on the Sun called coronal holes. The energy source responsible for accelerating the plasma to high speeds is widely debated, however there is evidence that it is ultimately magnetic in nature with candidate mechanisms including wave heating^(1,2) and interchange reconnection^(3,4,5). The coronal magnetic field near the solar surface is structured on scales associated with supergranulation convection cells, where descending flows create intense fields. The energy density in these network magnetic field bundles is a likely candidate as an energy source of the wind. Here we report measurements of fast solar wind streams from the Parker Solar Probe (PSP) spacecraft^6 which provides strong evidence for the interchange reconnection mechanism. We show that supergranulation structure at the coronal hole base remains imprinted in the near-Sun solar wind resulting in asymmetric patches of magnetic 'switchbacks'^(7,8) and bursty wind streams with power law-like energetic ion spectra to beyond 100 keV. Computer simulations of interchange reconnection support key features of the observations, including the ion spectra. Important characteristics of interchange reconnection in the low corona are inferred from the data including that the reconnection is collisionless and that the energy release rate is sufficient to power the fast wind. In this scenario, open magnetic flux undergoes continuous reconnection and the wind is driven both by the resulting plasma pressure and the radial Alfvenic flow bursts., 15 pages, 4 figures. Nature, 2023

A variety of energy sources, ranging from dynamic processes like magnetic reconnection and waves to quasi-steady terms like the plasma pressure, may contribute to the acceleration of the solar wind. We utilize a combination of charged particle and magnetic field observations from the Parker Solar Probe (PSP) to attempt to quantify the steady-state contribution of the proton pressure, the electric potential, and the wave energy to the solar wind proton acceleration observed by PSP between 13.3 and ~100 solar radii (RS). The proton pressure provides a natural kinematic driver of the outflow. The ambipolar electric potential acts to couple the electron pressure to the protons, providing another definite proton acceleration term. Fluctuations and waves, while inherently dynamic, can act as an additional effective steady-state pressure term. To analyze the contributions of these terms, we utilize radial binning of single-point PSP measurements, as well as repeated crossings of the same stream at different distances on individual PSP orbits (i.e. "fast radial scans"). In agreement with previous work, we find that the electric potential contains sufficient energy to fully explain the acceleration of the slower wind streams. On the other hand, we find that the wave pressure plays an increasingly important role in the faster wind streams. The combination of these terms can explain the continuing acceleration of both slow and fast wind streams beyond 13.3 RS.

Solar flares and the often associated solar eruptive events serve as an outstanding laboratory to study the magnetic reconnection and the associated energy release and conversion processes under plasma conditions difficult to reproduce in the laboratory, and with considerable spatiotemporal details not possible elsewhere in the universe. In the past decade, thanks to advances in multi-wavelength imaging spectroscopy, as well as developments in theories and numerical modeling, significant progress has been made in improving our understanding of solar flare/eruption energy release. In particular, broadband imaging spectroscopy at microwave wavelengths offered by the Expanded Owens Valley Solar Array (EOVSA) has enabled the revolutionary capability of measuring the time-evolving coronal magnetic fields at or near the flare reconnection region. However, owing to EOVSA's limited dynamic range, imaging fidelity, and angular resolution, such measurements can only be done in a region around the brightest source(s) where the signal-to-noise is sufficiently large. In this white paper, after a brief introduction to the outstanding questions and challenges pertinent to magnetic energy release in solar flares and eruptions, we will demonstrate how a next-generation radio facility with many (~100-200) antenna elements can bring the next revolution by enabling high dynamic range, high fidelity broadband imaging spectropolarimetry along with a sub-second time resolution and arcsecond-level angular resolution. We recommend to prioritize the implementation of such a ground-based instrument within this decade. We also call for facilitating multi-wavelength, multi-messenger observations and advanced numerical modeling in order to achieve a comprehensive understanding of the "system science" of solar flares and eruptions., Comment: Science white paper submitted to the 2024 Solar and Space Physics Decadal Survey. All submitted white papers (including this one) are available at https://www.nationalacademies.org/our-work/decadal-survey-for-solar-and-space-physics-heliophysics-2024-2033

We present EUV solar observations showing evidence for omnipresent jetting activity driven by small-scale magnetic reconnection at the base of the solar corona. We argue that the physical mechanism that heats and drives the solar wind at its source is ubiquitous magnetic reconnection in the form of small-scale jetting activity (a.k.a. jetlets). This jetting activity, like the solar wind and the heating of the coronal plasma, is ubiquitous regardless of the solar cycle phase. Each event arises from small-scale reconnection of opposite-polarity magnetic fields producing a short-lived jet of hot plasma and Alfvén waves into the corona. The discrete nature of these jetlet events leads to intermittent outflows from the corona, which homogenize as they propagate away from the Sun and form the solar wind. This discovery establishes the importance of small-scale magnetic reconnection in solar and stellar atmospheres in understanding ubiquitous phenomena such as coronal heating and solar wind acceleration. Based on previous analyses linking the switchbacks to the magnetic network, we also argue that these new observations might provide the link between the magnetic activity at the base of the corona and the switchback solar wind phenomenon. These new observations need to be put in the bigger picture of the role of magnetic reconnection and the diverse form of jetting in the solar atmosphere., The Astrophysical Journal, 945 (1), ISSN:0004-637X, ISSN:2041-8213

BackgroundWe previously developed an African-ancestry-specific polygenic hazard score (PHS46+African) that substantially improved prostate cancer risk stratification in men with African ancestry. The model consists of 46 SNPs identified in Europeans and 3 SNPs from 8q24 shown to improve model performance in Africans. Herein, we used principal component (PC) analysis to uncover subpopulations of men with African ancestry for whom the utility of PHS46+African may differ.Materials and methodsGenotypic data were obtained from the PRACTICAL consortium for 6253 men with African genetic ancestry. Genetic variation in a window spanning 3 African-specific 8q24 SNPs was estimated using 93 PCs. A Cox proportional hazards framework was used to identify the pair of PCs most strongly associated with the performance of PHS46+African. A calibration factor (CF) was formulated using Cox coefficients to quantify the extent to which the performance of PHS46+African varies with PC.ResultsCF of PHS46+African was strongly associated with the first and twentieth PCs. Predicted CF ranged from 0.41 to 2.94, suggesting that PHS46+African may be up to 7 times more beneficial to some African men than others. The explained relative risk for PHS46+African varied from 3.6% to 9.9% for individuals with low and high CF values, respectively. By cross-referencing our data set with 1000 Genomes, we identified significant associations between continental and calibration groupings.ConclusionWe identified PCs within 8q24 that were strongly associated with the performance of PHS46+African. Further research to improve the clinical utility of polygenic risk scores (or models) is needed to improve health outcomes for men of African ancestry.

The Frequency Agile Solar Radiotelescope (FASR) has been strongly endorsed as a top community priority by both Astronomy & Astrophysics Decadal Surveys and Solar & Space Physics Decadal Surveys in the past two decades. Although it was developed to a high state of readiness in previous years (it went through a CATE analysis and was declared ``doable now"), the NSF has not had the funding mechanisms in place to fund this mid-scale program. Now it does, and the community must seize this opportunity to modernize the FASR design and build the instrument in this decade. The concept and its science potential have been abundantly proven by the pathfinding Expanded Owens Valley Solar Array (EOVSA), which has demonstrated a small subset of FASR's key capabilities such as dynamically measuring the evolving magnetic field in eruptive flares, the temporal and spatial evolution of the electron energy distribution in flares, and the extensive coupling among dynamic components (flare, flux rope, current sheet). The FASR concept, which is orders of magnitude more powerful than EOVSA, is low-risk and extremely high reward, exploiting a fundamentally new research domain in solar and space weather physics. Utilizing dynamic broadband imaging spectropolarimetry at radio wavelengths, with its unique sensitivity to coronal magnetic fields and to both thermal plasma and nonthermal electrons from large flares to extremely weak transients, the ground-based FASR will make synoptic measurements of the coronal magnetic field and map emissions from the chromosphere to the middle corona in 3D. With its high spatial, spectral, and temporal resolution, as well as its superior imaging fidelity and dynamic range, FASR will be a highly complementary and synergistic component of solar and heliospheric capabilities needed for the next generation of solar science., White Paper submitted to the Solar and Space Physics 2024 Decadal Survey

Sussex Archaeological Collections, 128, 187-194, At the end of the 18th century Broadwater parish made no provision for the education of poor children. Following the national initiative by the church of England in 1811 the parish had established five day schools by 1818. In 1816 Robert Owen opened the first infant school in Scotland and a short while later similar schools began to be opened in England. After the success of these early schools there was controversy over their origin, with the parish publishing its own claim.

Polygenic hazard score (PHS) models are associated with age at diagnosis of prostate cancer. Our model developed in Europeans (PHS46) showed reduced performance in men with African genetic ancestry. We used a cross-validated search to identify single nucleotide polymorphisms (SNPs) that might improve performance in this population. Anonymized genotypic data were obtained from the PRACTICAL consortium for 6253 men with African genetic ancestry. Ten iterations of a 10-fold cross-validation search were conducted to select SNPs that would be included in the final PHS46+African model. The coefficients of PHS46+African were estimated in a Cox proportional hazards framework using age at diagnosis as the dependent variable and PHS46, and selected SNPs as predictors. The performance of PHS46 and PHS46+African was compared using the same cross-validated approach. Three SNPs (rs76229939, rs74421890 and rs5013678) were selected for inclusion in PHS46+African. All three SNPs are located on chromosome 8q24. PHS46+African showed substantial improvements in all performance metrics measured, including a 75% increase in the relative hazard of those in the upper 20% compared to the bottom 20% (2.47-4.34) and a 20% reduction in the relative hazard of those in the bottom 20% compared to the middle 40% (0.65-0.53). In conclusion, we identified three SNPs that substantially improved the association of PHS46 with age at diagnosis of prostate cancer in men with African genetic ancestry to levels comparable to Europeans.

One of the striking observations from the Parker Solar Probe (PSP) spacecraft is the prevalence in the inner heliosphere of large amplitude, Alfv��nic magnetic field reversals termed 'switchbacks'. These $��B_R/B \sim \mathcal{O}(1$) fluctuations occur on a range of timescales and in {\em patches} separated by intervals of quiet, radial magnetic field. We use measurements from PSP to demonstrate that patches of switchbacks are localized within the extensions of plasma structures originating at the base of the corona. These structures are characterized by an increase in alpha particle abundance, Mach number, plasma $��$ and pressure, and by depletions in the magnetic field magnitude and electron temperature. These intervals are in pressure-balance, implying stationary spatial structure, and the field depressions are consistent with overexpanded flux tubes. The structures are asymmetric in Carrington longitude with a steeper leading edge and a small ($\sim$1$^\circ$) edge of hotter plasma and enhanced magnetic field fluctuations. Some structures contain suprathermal ions to $\sim$85 keV that we argue are the energetic tail of the solar wind alpha population. The structures are separated in longitude by angular scales associated with supergranulation. This suggests that these switchbacks originate near the leading edge of the diverging magnetic field funnels associated with the network magnetic field - the primary wind sources. We propose an origin of the magnetic field switchbacks, hot plasma and suprathermals, alpha particles in interchange reconnection events just above the solar transition region and our measurements represent the extended regions of a turbulent outflow exhaust., 18 pages, 9 figures, submitted to Astrophys. J

Objective An increasing number of patients use social media for health-related information and social support. This study’s objective was to describe the content posted on Facebook groups for individuals with microtia and/or craniofacial microsomia (CFM) and their families in order for providers to gain insight into patient and family needs and experiences to inform clinical care. Methods Two months of posts, images, comments, and ‘like’ responses from two Facebook groups in the US and the UK were recorded and analyzed using content analysis. A secondary analysis identified statements of emotion. Results Posts (N=254) had a total of 7,912 “like” responses, 2,245 comments, and 153 images. There were three categories of posts: seeking guidance (43%; 9 themes), promoting events/news (33%; 5 themes), and sharing experiences (24%; 3 themes). Across categories, 16% of posts had emotional content. Most comments were responding to posts seeking guidance, including medical care (20%), surgical care (9%), and hearing aids (5%). Promotional posts often aimed to increase CFM awareness. Posts sharing experiences were generally positive, with the highest number of “likes”. Conclusions Facebook groups members frequently exchanged health-related information, suggesting value placed on input from other families and the convenience of seeking information online. Posts also promoted awareness and shared experiences. Clinical care implications include the need for easily accessible accurate and tailored CFM-related health education. Additionally, providers should demonstrate awareness of health information on social media and may address the potential emotional impact of CFM by facilitating access to resources for social support.

ObjectivesVeterans Health Administration (VHA) launched a national initiative to train providers in a specific, protocolized auricular acupuncture treatment (also called Battlefield Acupuncture or BFA) as a nonpharmacological approach to pain management. This evaluation assessed the real-world effectiveness of BFA on immediate pain relief and identified subgroups of patients for whom BFA is most effective.Research designIn a cross-sectional cohort study, electronic medical record data for 11,406 Veterans treated with BFA at 57 VHA medical centers between October 2016 and September 2018 was analyzed. The multivariate analysis incorporated data on pain history, change in pain level on an 11-point scale, complications, and demographic information.MethodsA total of 11,406 Veterans were treated with BFA at 57 VHA medical centers between October 2016 and September 2018 and had effectiveness data recorded in their electronic medical record.ResultsMore than 3 quarters experienced immediate decreases in pain following administration of BFA, with nearly 60% reported experiencing a minimal clinically important difference in pain intensity. The average decrease in pain intensity was -2.5 points (SD=2.2) at the initial BFA treatment, and -2.2 points (SD=2.0) at subsequent treatments. BFA was effective across a wide range of Veterans with many having preexisting chronic pain, or physical, or psychological comorbid conditions. Veterans with opioid use in the year before BFA experienced less improvement, with pain intensity scores improving more among Veterans who had not recently used opioids.ConclusionVHA's rapid expansion of training providers to offer BFA as a nonpharmacological approach to pain management has benefited many Veterans.

Transport equations for electron thermal energy in the high $\beta_e$ intracluster medium (ICM) are developed that include scattering from both classical collisions and self-generated whistler waves. The calculation employs an expansion of the kinetic electron equation along the ambient magnetic field in the limit of strong scattering and assumes whistler waves with low phase speeds $V_w\sim{v}_{te}/\beta_e\ll{v}_{te}$ dominate the turbulent spectrum, with $v_{te}$ the electron thermal speed and $\beta_e\gg1$ the ratio of electron thermal to magnetic pressure. We find: (1) temperature-gradient-driven whistlers dominate classical scattering when $L_c>L/\beta_e$, with $L_c$ the classical electron mean-free-path and $L$ the electron temperature scale length, and (2) in the whistler dominated regime the electron thermal flux is controlled by both advection at $V_w$ and a comparable diffusive term. The findings suggest whistlers limit electron heat flux over large regions of the ICM, including locations unstable to isobaric condensation. Consequences include: (1) the Field length decreases, extending the domain of thermal instability to smaller length-scales, (2) the heat flux temperature dependence changes from $T_e^{7/2}/L$ to $V_wnT_e\sim{T}_e^{1/2}$, (3) the magneto-thermal and heat-flux driven buoyancy instabilities are impaired or completely inhibited, and (4) sound waves in the ICM propagate greater distances, as inferred from observations. This description of thermal transport can be used in macroscale ICM models., Comment: Accepted for publication in The Astrophysical Journal

著者人数: 27名, Accepted: 2019-01-15, 資料番号: SA1180269000

Observations by the Parker Solar Probe mission of the solar wind at about 35 solar radii reveal the existence of whistler wave packets with frequencies below 0.1fce (20-150 Hz in the spacecraft frame). These waves bursts often coincide with local minima of the magnetic field magnitude observed in the vicinity of the switchbacks boundaries. The Poynting flux indicates sunward propagation that leads to a significant Doppler frequency downshift from 200-300 Hz to 20-80 Hz (from 0.2fce to 0.5fce). The polarization of these waves varies from quasi-parallel to significantly oblique. Their peak amplitude can be as large as 1-4 nT (up to 20% of the background magnetic field magnitude). The generation of these waves is supported by the modified electron distribution with increased transverse temperature anisotropy inside the magnetic hole. Sunward propagating whistler waves scatter the high energy solar wind electrons in the energy range up to 1 keV and potentially play a significant role in breaking the heat flux and scattering the Strahl population of suprathermal electrons into a halo population.

Transport equations for electron thermal energy in the high $��_e$ intracluster medium (ICM) are developed that include scattering from both classical collisions and self-generated whistler waves. The calculation employs an expansion of the kinetic electron equation along the ambient magnetic field in the limit of strong scattering and assumes whistler waves with low phase speeds $V_w\sim{v}_{te}/��_e\ll{v}_{te}$ dominate the turbulent spectrum, with $v_{te}$ the electron thermal speed and $��_e\gg1$ the ratio of electron thermal to magnetic pressure. We find: (1) temperature-gradient-driven whistlers dominate classical scattering when $L_c>L/��_e$, with $L_c$ the classical electron mean-free-path and $L$ the electron temperature scale length, and (2) in the whistler dominated regime the electron thermal flux is controlled by both advection at $V_w$ and a comparable diffusive term. The findings suggest whistlers limit electron heat flux over large regions of the ICM, including locations unstable to isobaric condensation. Consequences include: (1) the Field length decreases, extending the domain of thermal instability to smaller length-scales, (2) the heat flux temperature dependence changes from $T_e^{7/2}/L$ to $V_wnT_e\sim{T}_e^{1/2}$, (3) the magneto-thermal and heat-flux driven buoyancy instabilities are impaired or completely inhibited, and (4) sound waves in the ICM propagate greater distances, as inferred from observations. This description of thermal transport can be used in macroscale ICM models., Accepted for publication in The Astrophysical Journal

Kinetic particle-in-cell simulations are used to identify signatures of the electron diffusion region (EDR) and its surroundings during asymmetric magnetic reconnection. A "shoulder" in the sunward pointing normal electric field (EN > 0) at the reconnection magnetic field reversal is a good indicator of the EDR, and is caused by magnetosheath electron meandering orbits in the vicinity of the x-line. Earthward of the X-line, electrons accelerated by EN form strong currents and crescent-shaped distribution functions in the plane perpendicular to B. Just downstream of the X-line, parallel electric fields create field-aligned crescent electron distribution functions. In the immediate upstream magnetosheath, magnetic field strength, plasma density, and perpendicular electron temperatures are lower than the asymptotic state. In the magnetosphere inflow region, magnetosheath ions intrude resulting in an Earthward pointing electric field and parallel heating of magnetospheric particles. Many of the above properties persist with a guide field of at least unity., Submitted to Geophysical Research Letters

Magnetic reconnection is a fundamental physical process in many laboratory, space, and astrophysical plasma contexts. Solar flares serve as an outstanding laboratory to study the magnetic reconnection and the associated energy release and conversion processes under plasma conditions difficult to reproduce in the laboratory, and with considerable spatiotemporal details not possible elsewhere in astrophysics. Here we emphasize the unique power of remote-sensing observations of solar flares at radio wavelengths. In particular, we discuss the transformative technique of broadband radio dynamic imaging spectroscopy in making significant contributions to addressing several outstanding challenges in magnetic reconnection, including the capability of pinpointing magnetic reconnection sites, measuring the time-evolving reconnecting magnetic fields, and deriving the spatially and temporally resolved distribution function of flare-accelerated electrons., Submitted to the Astro2020 Decadal Survey call for science white papers (5 pages + references, 2 figures)

International audience; Antimicrobial peptides (AMPs) are a potential source of new molecules to counter the increase in antimicrobial resistant infections but a better understanding of their properties is required to understand their native function and for effective translation as therapeutics. Details of the mechanism of their interaction with the bacterial plasma membrane are desired since damage or penetration of this structure is considered essential for AMPs activity. Relatively modest modifications to AMPs primary sequence can induce substantial changes in potency and/or spectrum of activity but, hitherto, have not been predicted to substantially alter the mechanism of interaction with the bacterial plasma membrane. Here we use a combination of molecular dynamics simulations, circular dichroism, solidstate NMR and patch clamp to investigate the extent to which temporin B and its analogues can be distinguished both in vitro and in silico on the basis of their interactions with model membranes. Enhancing the hydrophobicity of the N-terminus and cationicity of the C-terminus in temporin B improves its membrane activity and potency against both Gram-negative and Gram-positive bacteria. In contrast, enhancing the cationicity of the N-terminus abrogates its ability to trigger channel conductance and renders it ineffective against Gram-positive bacteria while nevertheless enhancing its potency against Escherichia coli. Our findings suggest even closely related AMPs may target the same bacterium with fundamentally differing mechanisms of action.

Supplemental Material, S1_File_Abstraction_Med_Record_12_31_14 for Methods and Challenges in a Cohort Study of Infants and Toddlers With Craniofacial Microsomia: The Clock Study by Daniela V. Luquetti, Matthew L. Speltz, Erin R. Wallace, Babette Siebold, Brent R. Collett, Amelia F. Drake, Alexis L. Johns, Kathleen A. Kapp-Simon, Sara L. Kinter, Brian G. Leroux, Leanne Magee, Susan Norton, Kathleen Sie, and Carrie L. Heike in The Cleft Palate-Craniofacial Journal

Supplemental_Material for Methods and Challenges in a Cohort Study of Infants and Toddlers With Craniofacial Microsomia: The Clock Study by Daniela V. Luquetti, Matthew L. Speltz, Erin R. Wallace, Babette Siebold, Brent R. Collett, Amelia F. Drake, Alexis L. Johns, Kathleen A. Kapp-Simon, Sara L. Kinter, Brian G. Leroux, Leanne Magee, Susan Norton, Kathleen Sie, and Carrie L. Heike in The Cleft Palate-Craniofacial Journal

Kinetic Riemann simulations have been completed to explore particle heating during guide field reconnection in the low-$��$ environment of the inner heliosphere and the solar corona. The reconnection exhaust is bounded by two rotational discontinuities (RD) and two slow shocks (SS) form within the exhaust as in magnetohydrodynamic (MHD) models. At the RDs, ions are accelerated by the magnetic field tension to drive the reconnection outflow as well as flows in the out-of-plane direction. The out-of-plane flows stream toward the midplane and meet to drive the SSs. The SSs differ greatly from those in the MHD model. The turbulence at the shock fronts and both upstream and downstream is weak so the shocks are laminar and produce little dissipation. Downstream of the SSs the counterstreaming ion beams lead to higher density, which leads to a positive potential between the SSs that acts to confine the downstream electrons to maintain charge neutrality. The potential accelerates electrons from upstream of the SSs to downstream region and traps a small fraction but only modestly increases the downstream electron temperature above the upstream value. In the low-$��$ limit the released magnetic energy is split between bulk flow and ion heating with little energy going to electrons. That the model does not produce strong electron heating nor an energetic electron component suggests that other mechanisms, such as multiple x-line reconnection, are required to explain energetic electron production in large flares. The model can be tested with the expected data from the Parker Solar Probe., Some figures' quality is downgraded due to the size limit of arXiv

The NASA Parker Solar Probe mission has made its first set of solar encounters at 35.7 solar radii. The first encounters reveal a solar wind rich in instabilities and kinetic physics. The FIELDS instrument on PSP measures copious, intermittent burstsof electron plasma (Langmuir) waves throughout Encounters 1 and 2. These waves are purely electrostatic, to the sensitivity of the measurement, and have wave (electric field) vectors aligned with the solar wind magnetic field. We suggest that these Langmuir waves are generated on a Landau resonance by electron beams with beam speeds of 5-10 v_th. The duration of the bursts suggests beams of ~100-10000 km across the magnetic field. We examine the statistics and occurence conditions. Langmuir waves during Encounter 1 are definitively not associated with solar type III radio bursts. FIELDS also measures signatures of ion cyclotron waves and kinetic scale turbulence, with indications for energy exchange processes in the inner corona.

The role of turbulence in low-$��$, guide-field reconnection exhausts is explored in 2D reconnection and 2D and 3D Riemann simulations. The structure of the exhaust and associated turbulence is controlled by a pair of rotational discontinuities (RDs) at the exhaust boundary and a pair of slow shocks (SSs) that are generated by counterstreaming ions beams. In 2D the exhaust develops large-amplitude striations at the ion Larmor radius scale that are produced by electron-beam-driven ion cyclotron waves. The electron beams driving the instability are injected into the exhaust from one of the RDs. However, in 3D Riemann simulations, the additional dimension (in the out-of-plane direction) results in strong Buneman and electron-electron streaming instabilities at the RD which suppress electron beam formation and therefore the striations in the exhaust. The strength of the streaming instabilities at the RD are controlled by the ratio of the electron thermal speed to Alfv��n speed, lower thermal speed being more unstable. In the 3D simulations an ion-ion streaming instability acts to partially thermalize the counterstreaming ion beams at the SSs. This instability is controlled by the ratio of the sound speed to Alfv��n speed and is expected to be stable in the low $��$ solar corona. The results suggest that in a guide field reconnection exhaust with $1 \gg ��> m_e/m_i$, the kinetic-scale turbulence that develops will be too weak to play a significant role in energy conversion and particle acceleration. Therefore, the energy conversion will be mostly controlled by laminar physics or multi-x-line reconnection.

Convection and rotation drive the solar dynamo and, ultimately, provide the mechanical energy flux required to heat the solar corona and accelerate the solar wind. However, the way in which energy is then dissipated to heat the corona and wind are not well understood. Some energization models invoke non-thermal energy flux imparted by plasma Alfvén waves, while others rely on a carpet of small nano-flares as energy input, however these models have been unconstrained by direct measurements of the solar wind near its origin. Here we use in situ measurements from the FIELDS instrument suite during the first solar encounter (E1) at 35.7 solar radii (Rs) of the NASA Parker Solar Probe (PSP) mission to reveal the magnetic structure and kinetics of slow Alfvénic solar wind emerging from a small, equatorial coronal hole. Our measurements show that, at solar minimum, the slow wind can escape from above the low-lying, complex magnetic structures of the equatorial streamer belt, carrying a magnetic field that is highly dynamic, exhibiting polarity reversals on timescales from seconds to hours. These rapidly oscillating field structures are associated with clustered radial jets of plasma in which the energy flux is dramatically enhanced and turbulence levels are higher. Time intervals between groups of jets indicate a solar wind that is steady with a mostly radial magnetic field and relatively low levels of Alfvénic turbulent fluctuations. This 'quiet' wind however shows clear signatures of plasma micro-instabilities associated with ion and electron beams and velocity-space structure.

International audience; Observations by the Van Allen Probes and THEMIS provide high-quality ELF/VLF measurements of wave electric field that revealed the new nonlinear electron scales features in the outer radiation. The process of chorus generation significantly modify the local electron distribution function leading to forming the field aligned electron flux. The parallel electric field component of whistler-mode waves provides trapping of hot electrons into the effective potential and in inhomogeneous systems such as the dipole-like geomagnetic field allow an efficient parallel acceleration up to ~20-200 keV eventually leading to bursty precipitation (observed as microbursts at ionospheric altitudes). The mechanisms that produce nonlinear electric field structures, including the nonlinear evolution of oblique whistler-mode waves due to electron trapping and the parametric interaction of whistler waves have been determined. Important nonlinear processes responsible for rapid particle acceleration or scattering, with a significant effect on the global dynamics of the outer radiation belt, are: generation of chorus waves and corresponding generation of field aligned electron flux; whistler-mode waves with a large parallel electrostatic component providing Landau trapping into the wave effective potential with rapid parallel acceleration and possible bursty precipitation; lower energy electron population and filed aligned beams provide the possibility for nonlinear wave-wave coupling of whistlers and generation of electron acoustic mode and localized electric field bursts; nonlinear wave-particle interactions with oblique whistlers influence the global dynamics of the electron distribution in the outer radiation belt leading to separate observations of intense very oblique and parallel chorus in the outer radiation belt.

International audience

Chromosome 8q24 is a susceptibility locus for multiple cancers, including prostate cancer. Here we combine genetic data across the 8q24 susceptibility region from 71,535 prostate cancer cases and 52,935 controls of European ancestry to define the overall contribution of germline variation at 8q24 to prostate cancer risk. We identify 12 independent risk signals for prostate cancer (p, Chromosome 8q24 is known to be a major susceptibility region for prostate cancer risk. Here the authors analyze genetic data across the 8q24 region from 71,535 prostate cancer patients identifying 12 risk loci, three previously unreported, highlighting the contribution of germline variation at this locus.

International audience

© 2018 The Author(s). Genome-wide association studies (GWAS) and fine-mapping efforts to date have identified more than 100 prostate cancer (PrCa)-susceptibility loci. We meta-analyzed genotype data from a custom high-density array of 46,939 PrCa cases and 27,910 controls of European ancestry with previously genotyped data of 32,255 PrCa cases and 33,202 controls of European ancestry. Our analysis identified 62 novel loci associated (P < 5.0 × 10-8) with PrCa and one locus significantly associated with early-onset PrCa (≤55 years). Our findings include missense variants rs1800057 (odds ratio (OR) = 1.16; P = 8.2 × 10-9; G>C, p.Pro1054Arg) in ATM and rs2066827 (OR = 1.06; P = 2.3 × 10-9; T>G, p.Val109Gly) in CDKN1B. The combination of all loci captured 28.4% of the PrCa familial relative risk, and a polygenic risk score conferred an elevated PrCa risk for men in the ninetieth to ninety-ninth percentiles (relative risk = 2.69; 95% confidence interval (CI): 2.55-2.82) and first percentile (relative risk = 5.71; 95% CI: 5.04-6.48) risk stratum compared with the population average. These findings improve risk prediction, enhance fine-mapping, and provide insight into the underlying biology of PrCa 1 .

© 2018 The Author(s). Prostate cancer is a polygenic disease with a large heritable component. A number of common, low-penetrance prostate cancer risk loci have been identified through GWAS. Here we apply the Bayesian multivariate variable selection algorithm JAM to fine-map 84 prostate cancer susceptibility loci, using summary data from a large European ancestry meta-analysis. We observe evidence for multiple independent signals at 12 regions and 99 risk signals overall. Only 15 original GWAS tag SNPs remain among the catalogue of candidate variants identified; the remainder are replaced by more likely candidates. Biological annotation of our credible set of variants indicates significant enrichment within promoter and enhancer elements, and transcription factor-binding sites, including AR, ERG and FOXA1. In 40 regions at least one variant is colocalised with an eQTL in prostate cancer tissue. The refined set of candidate variants substantially increase the proportion of familial relative risk explained by these known susceptibility regions, which highlights the importance of fine-mapping studies and has implications for clinical risk profiling.

Prostate cancer is a polygenic disease with a large heritable component. A number of common, low-penetrance prostate cancer risk loci have been identified through GWAS. Here we apply the Bayesian multivariate variable selection algorithm JAM to fine-map 84 prostate cancer susceptibility loci, using summary data from a large European ancestry meta-analysis. We observe evidence for multiple independent signals at 12 regions and 99 risk signals overall. Only 15 original GWAS tag SNPs remain among the catalogue of candidate variants identified; the remainder are replaced by more likely candidates. Biological annotation of our credible set of variants indicates significant enrichment within promoter and enhancer elements, and transcription factor-binding sites, including AR, ERG and FOXA1. In 40 regions at least one variant is colocalised with an eQTL in prostate cancer tissue. The refined set of candidate variants substantially increase the proportion of familial relative risk explained by these known susceptibility regions, which highlights the importance of fine-mapping studies and has implications for clinical risk profiling.

The outflow velocity of jets produced by collisionless magnetic reconnection is shown to be reduced by the ion exhaust temperature in simulations and observations. We derive a scaling relationship for the outflow velocity based on the upstream Alfv��n speed and the parallel ion exhaust temperature, which is verified in kinetic simulations and observations. The outflow speed reduction is shown to be due to the firehose instability criterion, and so for large enough guide fields this effect is suppressed and the outflow speed reaches the upstream Alfv��n speed based on the reconnecting component of the magnetic field.

International audience; Observations by the Van Allen Probes and THEMIS provide high-quality ELF/VLF measurements of wave electric field that revealed the new nonlinear electron scales features in the outer radiation belt, important for particle acceleration and scattering and showing the influence of nonlinear wave-particle interactions on the energetic electron distribution over macroscopic spatial scales. The parallel electric field component of whistler-mode waves provides trapping of hot electrons into the effective potential and in inhomogeneous systems such as the dipole-like geomagnetic field allow an efficient parallel acceleration up to 20-200 keV eventually leading to bursty precipitation (observed as microbursts at ionospheric altitudes). The mechanisms that produce nonlinear electric field structures, including the nonlinear evolution of oblique whistler-mode waves due to electron trapping and the parametric interaction of whistler waves have been determined. Important nonlinear processes responsible for rapid particle acceleration or scattering, with a significant effect on the global dynamics of the outer radiation belt, are listed below: - the distribution of high amplitude whistler-mode waves (oblique and parallel) and resonant electron distribution function features in the outer radiation belt are connected self-consistently; - whistler-mode waves with a large parallel electrostatic component (up to 100 mV/m) may allow Landau trapping of hot electrons into the wave effective potential with rapid parallel acceleration and possible bursty precipitation; - a prevalence of the hot electron population provides the possibility of generating an electron acoustic mode, and corresponding mechanisms of nonlinear wave-wave coupling lead to the formation of nonlinear parallel electric field bursts from oblique whistlers; - nonlinear wave-particle interactions with oblique whistlers influence the global dynamics of the electron distribution in the outer radiation belt leading to separate observations of intense very oblique and parallel chorus in the outer radiation belt.

Lagrangian analysis is a powerful way to analyse the output of ocean circulation models and other ocean velocity data such as from altimetry. In the Lagrangian approach, large sets of virtual particles are integrated within the three-dimensional, time-evolving velocity fields. Over several decades, a variety of tools and methods for this purpose have emerged. Here, we review the state of the art in the field of Lagrangian analysis of ocean velocity data, starting from a fundamental kinematic framework and with a focus on large-scale open ocean applications. Beyond the use of explicit velocity fields, we consider the influence of unresolved physics and dynamics on particle trajectories. We comprehensively list and discuss the tools currently available for tracking virtual particles. We then showcase some of the innovative applications of trajectory data, and conclude with some open questions and an outlook. The overall goal of this review paper is to reconcile some of the different techniques and methods in Lagrangian ocean analysis, while recognising the rich diversity of codes that have and continue to emerge, and the challenges of the coming age of petascale computing.

著者人数: 31名, Accepted: 2018-01-30, 資料番号: SA1180001000

Accepted: 2014-09-26, 資料番号: SA1005062000

著者人数: 88名, Accepted: 2014-01-24, 資料番号: SA1140010000

Accepted: 2013-08-28, 資料番号: SA1004594000

International audience; Observations of magnetic reconnection at Earth's magnetopause often display asymmetric structures that are accompanied by strong magnetic field (B) fluctuations and large-amplitude parallel electric fields (E||). The B turbulence is most intense at frequencies above the ion cyclotron frequency and below the lower hybrid frequency. The B fluctuations are consistent with a thin, oscillating current sheet that is corrugated along the electron flow direction (along the X line), which is a type of electromagnetic drift wave. Near the X line, electron flow is primarily due to a Hall electric field, which diverts ion flow in asymmetric reconnection and accompanies the instability. Importantly, the drift waves appear to drive strong parallel currents which, in turn, generate large-amplitude ( 100 mV/m) E|| in the form of nonlinear waves and structures. These observations suggest that turbulence may be common in asymmetric reconnection, penetrate into the electron diffusion region, and possibly influence the magnetic reconnection process.

Data from the NASA Magnetospheric Multiscale (MMS) mission are used to investigate asymmetric magnetic reconnection at the dayside boundary between the Earth's magnetosphere and the solar wind (the magnetopause). High-resolution measurements of plasmas, electric and magnetic fields, and waves are used to identify highly localized (~15 electron Debye lengths) standing wave structures with large electric-field amplitudes (up to 100 mV/m). These wave structures are associated with spatially oscillatory dissipation, which appears as alternatingly positive and negative values of J dot E (dissipation). For small guide magnetic fields the wave structures occur in the electron stagnation region at the magnetosphere edge of the EDR. For larger guide fields the structures also occur near the reconnection x-line. This difference is explained in terms of channels for the out-of-plane current (agyrotropic electrons at the stagnation point and guide-field-aligned electrons at the x-line).

The UV absorption and electronic circular dichroism (ECD) spectra of (R)- and (S)-nicotine and (S)-nornicotine in aqueous solution were measured to a significantly lower wavelength range than previously reported, allowing the identification of four previously unobserved electronic transitions. The ECD spectra of the two enantiomers of nicotine were equal in magnitude and opposite in sign, while the UV absorption spectra were coincidental. In line with previous observations, (S)-nicotine exhibited a negative cotton effect centered on 263 nm with vibronic structure (π–π1* transition) and a broad, positive ECD signal at around 240 nm associated with the n–π1* transition. As expected this band disappeared when the pyridyl aromatic moiety was protonated. Four further electronic transitions are reported between 215 and 180 nm; it is proposed the negative maxima around 206 nm is either an n–σ* transition or a charge transfer band resulting from the movement of charge from the pyrrolidyl N lone pair to the pyridyl π* orbital. The pyridyl π–π2* transition may be contained within the negative ECD signal envelope at around 200 nm. Another negative maximum at 188 nm is thought to be the pyridyl π–π3* transition, while the lowest wavelength end-absorption and positive ECD may be associated with the π–π4* transition. The UV absorption spectra of (S)-nornicotine was similar to that of (S)-nicotine in the range 280–220 nm and acidification of the aqueous solution enhanced the absorption. The ECD signals of (S)-nornicotine were considerably less intense compared to (S)-nicotine and declined further on acidification; in the far UV region the ECD spectra diverge considerably. Chirality 25:288–293, 2013. © 2013 Wiley Periodicals, Inc.

Accepted: 2012-11-29, 資料番号: SA1004871000

Although the importance of community engagement in research has been previously established, there are few evidence-based approaches for measuring the level of community engagement in research projects. A quantitative community engagement measure was developed, aligned with 11 engagement principles (EPs) previously established in the literature. The measure has 96 Likert response items; 3–5 quality items and 3–5 quantity items measure each EP. Cronbach’s alpha is used to examine the internal consistency of items that measure a single EP. Every EP item group had a Cronbach’s alpha > .85, which indicates strong internal consistency for all question groups across both scales (quality and quantity). This information determines the level of community engagement, which can be correlated with other research outcomes.

©2016. American Geophysical Union. All Rights Reserved.We report observations from the Magnetospheric Multiscale satellites of large-amplitude, parallel, electrostatic waves associated with magnetic reconnection at the Earths magnetopause. The observed waves have parallel electric fields (E||) with amplitudes on the order of 100 mV/m and display nonlinear characteristics that suggest a possible net E||. These waves are observed within the ion diffusion region and adjacent to (within several electron skin depths) the electron diffusion region. They are in or near the magnetosphere side current layer. Simulation results support that the strong electrostatic linear and nonlinear wave activities appear to be driven by a two stream instability, which is a consequence of mixing cold (

著者人数: 30名, Accepted: 2016-05-09, 資料番号: SA1160276000

著者人数: 30名, Accepted: 2016-06-03, 資料番号: SA1160277000

Understanding the thermodynamic state of the hot intracluster medium (ICM) in a galaxy cluster requires a knowledge of the plasma transport processes, especially thermal conduction. The basic physics of thermal conduction in plasmas with ICM-like conditions has yet to be elucidated, however. We use particle-in-cell simulations and analytic models to explore the dynamics of an ICM-like plasma (with small gyroradius, large mean-free-path, and strongly sub-dominant magnetic pressure) driven by the diffusive heat flux associated with thermal conduction. Lin- ear theory reveals that whistler waves are driven unstable electron heat flux, even when the heat flux is weak. The resonant interaction of electrons with these waves then plays a critical role in scattering electrons and suppressing the heat flux. In a 1D model where only whistler modes that are parallel to the magnetic field are captured, the only resonant electrons are moving in the opposite direction to the heat flux and the electron heat flux suppression is small. In 2D or more, oblique whistler modes also resonate with electrons moving in the direction of the heat flux. The overlap of resonances leads to effective symmetrization of the electron distribution function and a strong suppression of heat flux. The results suggest that thermal conduction in the ICM might be strongly suppressed, possibly to negligible levels., 8 pages, 4 figures. To be published in ApJ Letters

Sandberg, John B., Serpa, Larry E., Drake, Eugene F. (2015): The Drumming Signals Of Three Winter Stonefly Species (Capniidae, Leuctridae: Plecoptera); With Discussion Resolving Two Common Interval Patterns. Illiesia 11 (6): 51-74, DOI: http://doi.org/10.5281/zenodo.4760932, {"references":["Abbott, J.C. and Stewart, K.W. 1997. Drumming of three Mesocapnia species (Capniidae) and Soliperla thyra (Peltoperlidae) from California, U.S.A, pp. 88-92. In: P. Landolt & M. Satori (eds.), Ephemeroptera & Plecoptera: Biology- Ecology-Systematics. MTL, Fribourg.","Graham, E.A. 1982. Drumming communication and pre-mating behavior of fourteen Nearctic stonefly (Plecoptera) species. M.S. Thesis. University of Wisconsin-Stevens Point. 79 pp.","Sandberg, J.B. 2011a. Vibrational communication of Isoperla Banks from California and Oregon (Plecoptera: Perlodidae). Illiesia, 7:1-23.","Sandberg, J.B. 2011b. Vibrational communication of seven California stoneflies (Plecoptera: Perlodidae). The Pan-Pacific Entomologist, 87:71-85.","Sandberg, J.B. 2011c. Vibrational communication of nine California stonefly (Plecoptera) species. Western North American Naturalist, 71:285-301.","Sandberg, J.B. 2009. Vibrational communication (drumming) of the western Nearctic stonefly genus Hesperoperla (Plecoptera: Perlidae). Illiesia, 5:146-155.","Sandberg, J.B. and K.W. Stewart. 2003. Continued studies of drumming in North American Plecoptera; Evolutionary implications, pp.73-81. In: E. Gaino (ed.), Research update on Ephemeroptera & Plecoptera. Perugia, Italy.","Snellen, R.K. and K.W. Stewart. 1979. The life cycle and drumming behavior of Zealeuctra claasseni (Frison) and Zealeuctra hitei Ricker and Ross (Plecoptera: Leuctridae) in Texas, USA. Aquatic Insects, 1:65-89.","Stewart, K.W. 2001. Vibrational communication (drumming) and mate searching behavior of stoneflies (Plecoptera); Evolutionary considerations, pp. 217-225. In E. Dominguez (ed.), Trends in Research in Ephemeroptera and Plecoptera. Kluwer Academic/Plenum Publishers, NY.","Stewart, K.W. and J.B. Sandberg. 2006. Vibrational communication and mate searching behavior in stoneflies, pp. 179-186. In: S. Drosopoulos & M. Claridge (eds.), Insect Sounds and Communication: Physiology, Behavior, Ecology and Evolution, CRC Press, Boca Raton, London, New York.","Stewart, K.W. and J.B. Sandberg. 2004. Description of the nymph and drumming calls of Megaleuctra complicata Claassen (Plecoptera: Leuctridae); Evolution of drumming in Leuctridae. Aquatic Insects, 26:123-129.","Stewart, K.W. and D.D. Zeigler. 1984. Drumming behavior of twelve North American stonefly (Plecoptera) species: first descriptions in Peltoperlidae, Taeniopterygidae and Chloroperlidae. Aquatic Insects, 6:49-61.","Stewart, K.W., J.C. Abbott, R.F. Kirchner, and S.R. Moulton II. 1995. New descriptions of North American Euholognathan stonefly drumming (Plecoptera) and first Nemouridae ancestral call discovered in Soyedina carolinensis (Plecoptera: Nemouridae). Annals of the Entomological Society of America, 88:234-239.","Stewart, K.W., R.L. Bottorff, A.W. Knight, and J.B. Moring. 1991. Drumming of four North American Euholognathan stonefly species, and a new complex signal pattern in Nemoura spiniloba Jewett (Plecoptera: Nemouridae). Annals of the Entomological Society of America, 84:201-206.","Zeigler, D.D. 1989. Drumming behavior of three Pennsylvania stonefly (Plecoptera) species. Proceedings of the Entomological Society of Washington, 9:583-587.","Zeigler, D.D. and K.W. Stewart. 1977. Drumming behavior of eleven Nearctic stonefly (Plecoptera) species. Annals of the Entomological Society of America, 70:495-505.","Bottorff, R.L., K.W. Stewart, & A.W. Knight. 1989. Description and drumming of Susulus, a new genus of stonefly (Plecoptera: Perlodidae) from California, Ann. Entomol. Soc. Am., 82 (5):545- 554.","Bottorff, R.L., S.W. Szczytko, A.W. Knight, & J.J. Dimick, 1990. Drumming behavior of four western Nearctic Isoperla species (Plecoptera: Perlodidae), Ann. Entomol. Soc. Am., 83 (5):992- 997.","Hassage, R.L., K.W. Stewart, & D.D. Zeigler. 1988. Female response to computer-simulated male drumming call variations in Pteronarcella badia (Plecoptera: Pteronarcyidae), Ann. Entomol. Soc. Am., 81 (3):528-531.","Kondratieff, B.C., Kirchner, R.F. & K.W. Stewart. 1988. A review of Perlinella Banks (Plecoptera: Perlidae), Ann. Entomol. Soc. Am., 81 (1):19-27.","Maketon, M. & K.W. Stewart. 1984. Drumming behavior in four North American Perlodidae (Plecoptera) species, Ann. Entomol. Soc. Am., 77 (5):621-626.","Maketon, M. & K.W. Stewart. 1984. Further studies of the drumming behavior of North American Perlidae (Plecoptera), Ann. Entomol. Soc. Am., 77 (6):770-778.","Maketon, M., K.W. Stewart, B.C. Kondratieff, and R.F. Kirchner. 1988. New descriptions and evolution of the behavior in North American Perlodidae (Plecoptera). Journal of the Kansas Entomological Society, 61:161-168.","Sandberg, J.B. & K.W. Stewart. 2001. Drumming behavior and life history notes of a high-altitude Colorado population of the stonefly Isoperla pertersoni Needham & Christenson (Plecoptera: Perlodidae), Western North Am. Naturalist, 61 (4):445-451.","Sandberg, J.B. & K.W. Stewart. 2005. Vibrational communication (Drumming) of the Nearctic stonefly genus Isogenoides (Plecoptera: Perlodidae), Trans. Am. Entomol. Soc., 131 (1+2):111-130.","Sandberg, J.B. & K.W. Stewart. 2006. Continued studies of vibrational communication (drumming) of North American Plecoptera, Illiesia, 2 (1):1-14.","Stewart, K.W. & M. Maketon. 1990. Intraspecific variation and information content of drumming in three Plecoptera species, pp. 102-106. In: I.C. Campbell (ed.), Mayflies and Stoneflies, Kluwer Academic Publishers, Dordrecht.","Stewart, K.W., Abbott, J.C. & R.L. Bottorff. 1995. The drumming behavior of two stonefly species Cosumnoperla hypocrena (Perlodidae) and Paraperla wilsoni (Chloroperlidae); A newly discovered duet pattern in Plecoptera, Ent. News, 106 (1):13-18.","Stewart, K.W., S.W. Szczytko, & M. Maketon, 1988. Drumming as a behavioral line of evidence for delineating species in the genera Isoperla, Pteronarcys and Taeniopteryx (Plecoptera), Ann. Entomol. Soc. Am., 81 (4):689-699.","Stewart, K.W., S.W. Szczytko, & B.P. Stark. 1982. Drumming behavior of four species of North American Pteronarcyidae (Plecoptera): Dialects in Colorado and Alaska Pteronarcella badia, Ann. Entomol. Soc. Am., 75 (5):530-533.","Stewart, K.W., S.W. Szczytko, B.P. Stark, & D.D. Zeigler. 1982. Drumming behavior of six North American Perlidae (Plecoptera) species, Ann. Entomol. Soc. Am., 75 (5):549-554.","Szczytko, S.W. & K.W. Stewart. 1979. Drumming behavior of four western Nearctic Isoperla (Plecoptera) species, Ann. Entomol. Soc. Am., 72 (6):781-786.","Zeigler, D.D. & K.W. Stewart. 1985. Drumming behavior of five stonefly (Plecoptera) species from central and western North America, Ann. Entomol. Soc. Am., 78 (6):717-722.","Ziminske, M.T. 1989. Drumming behavior of selected stonefly (Plecoptera) species from the Great Lakes region, UWSP Master's Thesis, 60 pp."]}