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According to the CDC, there are more than 2.8 million antibiotic resistant infections occurring in the United States each year, and more than 35,000 people die as a result (CDC 2019). Furthermore, the CDC classifies a group of bacteria known as ESKAPE pathogens as six emerging antibiotic-resistant pathogens that are difficult to eradicate with current antibiotics. Our study aims to identify and characterize soil-derived microorganisms with the potential to produce antimicrobial compounds effective against safe relatives of ESKAPE pathogens, with the goal of translating these findings to combat their pathogenic counterparts. We hypothesize that bacteria identified from the soil will inhibit the growth of the following nosocomial associated safe relatives Bacillus subtilis for E. faecium, Staphylococcus epidermidis for S. aureus, Escherichia coli for Klebsiella pneumoniae, Acinetobacter baylyi for A. baumannii, Pseudomonas putida for P. aeruginosa, and Enterobacter aerogenes for Enterobacter species. To test our hypothesis, soil samples were collected from Fayetteville State University (FSU) campus and serially diluted onto LB agar plates. Sixty-three distinct colonies were isolated and screened against non-pathogenic ESKAPE safe relatives. Of the 63 Fayetteville State University soil isolates (FSIs) screened, 12 (19%) exhibited antimicrobial activity against at least one of the six ESKAPE safe relatives, with all 12 inhibiting Acinetobacter baylyi and only FSI 15 demonstrating broad-spectrum inhibition. Characterization assays revealed that 11 of the 12 isolates were Gram-negative, catalase-positive, and motile; the single Gram-positive isolate (FSI 4) was catalase-negative and non-motile. All isolates displayed resistance to penicillin, while most remained susceptible to tetracycline and ciprofloxacin. These findings support our hypothesis that soil-derived bacteria can produce putative antimicrobial compounds effective against non-pathogenic ESKAPE safe relatives. This study underscores the potential of soil microbiota on the campus of Fayetteville State University as a source of novel antimicrobial agents capable of inhibiting antibiotic resistant ESKAPE pathogens and warrant further investigation into their therapeutic potential 

Abstract This short article highlights unsolved problems of magnetic reconnection in collisionless plasma. Advanced in-situ plasma measurements and simulations have enabled scientists to gain a novel understanding of magnetic reconnection. Nevertheless, outstanding questions remain concerning the complex dynamics and structures in the diffusion region, cross-scale and regional couplings, the onset of magnetic reconnection, and the details of particle energization. We discuss future directions for magnetic reconnection research, including new observations, new simulations, and interdisciplinary approaches. 

Context.The evolution of the solar wind electron distribution function with heliocentric distance exhibits different features that are still unexplained, in particular, the fast decrease in the electron heat flux and the increase in the Strahl pitch angle width. Wave-particle interactions between electrons and whistler waves are often proposed to explain these phenomena. Aims.We aim to quantify the effect of whistler waves on suprathermal electrons as a function of heliocentric distance. Methods.We first performed a statistical analysis of whistler waves (occurrence and properties) observed by Solar Orbiter and Parker Solar Probe between 0.2 and 1 AU. The wave characteristics were then used to compute the diffusion coefficients for solar wind suprathermal electrons in the framework of quasi-linear theory. These coefficients were integrated to deduce the overall effect of whistler waves on electrons along their propagation. Results.About 110 000 whistler wave packets were detected and characterized in the plasma frame, including their direction of propagation with respect to the background magnetic field and their radial direction of propagation. Most waves are aligned with the magnetic field and only ∼0.5% of them have a propagation angle greater than 45°. Beyond 0.3 AU, it is almost exclusively quasi-parallel waves propagating anti-sunward (some of them are found sunward but are within switchbacks with a change of sign of the radial component of the background magnetic) that are observed. Thus, these waves are found to be Strahl-aligned and not counter-streaming. At 0.2 AU, we find both Strahl-aligned and counter-streaming quasi-parallel whistler waves. Conclusions.Beyond 0.3 AU, the integrated diffusion coefficients show that the observed waves are sufficient to explain the measured Strahl pitch angle evolution and effective in isotropizing the halo. Strahl diffusion is mainly attributed to whistler waves with a propagation angle ofθ ∈ [15.45]°, although their origin has not yet been fully determined. Near 0.2 AU, counter-streaming whistler waves are able to diffuse the Strahl electrons more efficiently than the Strahl-aligned waves by two orders of magnitude. 

Abstract This article articulates conceptual and methodological strategies for studying the dynamic structure of dyadic interaction revealed by the turn-to-turn exchange of messages between partners. Using dyadic time series data that capture partners’ back-and-forth contributions to conversations, dynamic dyadic systems analysis illuminates how individuals act and react to each other as they jointly construct conversations. Five layers of inquiry are offered, each of which yields theoretically relevant information: (a) identifying the individual moves and dyadic spaces that set the stage for dyadic interaction; (b) summarizing conversational units and sequences; (c) examining between-dyad differences in overall conversational structure; (d) describing the temporal evolution of conversational units and sequences; and (e) mapping within-dyad dynamics of conversations and between-dyad differences in those dynamics. Each layer of analysis is illustrated using examples from research on supportive conversations, and the application of dynamic dyadic systems analysis to a range of interpersonal communication phenomena is discussed. 

Abstract Coulomb collisions provide plasma resistivity and diffusion but in many low-density astrophysical plasmas such collisions between particles are extremely rare. Scattering of particles by electromagnetic waves can lower the plasma conductivity. Such anomalous resistivity due to wave-particle interactions could be crucial to many processes, including magnetic reconnection. It has been suggested that waves provide both diffusion and resistivity, which can support the reconnection electric field, but this requires direct observation to confirm. Here, we directly quantify anomalous resistivity, viscosity, and cross-field electron diffusion associated with lower hybrid waves using measurements from the four Magnetospheric Multiscale (MMS) spacecraft. We show that anomalous resistivity is approximately balanced by anomalous viscosity, and thus the waves do not contribute to the reconnection electric field. However, the waves do produce an anomalous electron drift and diffusion across the current layer associated with magnetic reconnection. This leads to relaxation of density gradients at timescales of order the ion cyclotron period, and hence modifies the reconnection process. 

Abstract Young mafic lavas from the East African Western Rift record melting of subcontinental lithospheric mantle that was metasomatically modified by multiple tectonic events. We report new isotope data from monogenetic cinder cones near Bufumbira, Uganda, in the Virunga Volcanic Field:⁸⁷Sr/⁸⁶Sr = 0.7059–0.7079,ε_Nd = −6.5 to −1.3,ε_Hf = −6.3 to +0.9,²⁰⁸Pb/²⁰⁴Pb = 40.1–40.7,²⁰⁷Pb/²⁰⁴Pb = 15.68–15.75, and²⁰⁶Pb/²⁰⁴Pb = 19.27–19.45. Olivine phenocrysts from the Bufumbira lavas have³He/⁴He = 6.0–7.4R_A. The isotopic data, in conjunction with major and trace element systematics, indicate that primitive Bufumbira magmas are derived from two different metasomatized lithospheric source domains. Melts generated by lower degrees of melting record greater contributions from ∼1 to 2 Ga isotopically enriched garnet‐amphibole‐phlogopite pyroxenite veins within the lithosphere. As melting progresses, these vein melts become increasingly diluted by melts that originate near the lithosphere/asthenosphere boundary, shifting the isotopic compositions toward the common lithospheric mantle (CLM) proposed by Furman and Graham (1999,https://doi.org/10.1016/s0024-4937(99)00031-6). This ∼450–500 Ma source domain appears to underlie all Western Rift volcanic provinces and is characterized by⁸⁷Sr/⁸⁶Sr ∼ 0.705,ε_Nd∼ 0,ε_Hf∼ +1 to +3,²⁰⁶Pb/²⁰⁴Pb ∼ 19.0–19.2,²⁰⁸Pb/²⁰⁴Pb ∼ 39.7, and³He/⁴He ∼ 7R_A. Basal portions of the dense subcontinental lithospheric mantle may become gravitationally unstable and founder into underlying warmer asthenosphere, exposing surfaces where melting of locally heterogeneous veins produces small‐volume, alkaline mafic melts. Mafic lavas from all Western Rift volcanic provinces record mixing between the CLM and locally variable metasomatized source domains, suggesting this style of melt generation is fundamental to the development of magma‐poor rifts.