How a realistic magnetosphere alters the polarizations of surface, fast magnetosonic, and Alfvén waves

System-scale magnetohydrodynamic (MHD) waves within Earth's magnetosphere are often understood theoretically using box models. While these have been highly instructive in understanding many fundamental features of the various wave modes present, they neglect the complexities of geospace such as the inhomogeneities and curvilinear geometries present. Here, we show global MHD simulations of resonant waves impulsively excited by a solar wind pressure pulse. Although many aspects of the surface, fast magnetosonic (cavity/waveguide), and Alfvén modes present agree with the box and axially symmetric dipole models, we find some predictions for large-scale waves are significantly altered in a realistic magnetosphere. The radial ordering of fast mode turning points and Alfvén resonant locations may be reversed even with monotonic wave speeds. Additional nodes along field lines that are not present in the displacement/velocity occur in both the perpendicular and compressional components of the magnetic field. Close to the magnetopause, the perpendicular oscillations of the magnetic field have the opposite handedness to the velocity. Finally, widely used detection techniques for standing waves, both across and along the field, can fail to identify their presence. We explain how all these features arise from the MHD equations when accounting for a non-uniform background field and propose modified methods that might be applied to spacecraft observations

How a realistic magnetosphere alters the polarizations of surface, fast magnetosonic, and Alfvén waves

Funding: MOA holds a UKRI (STFC / EPSRC) Stephen Hawking Fellowship EP/T01735X/1. DJS was supported by STFC grant ST/S000364/1. MDH was supported by NASA grant 80NSSC19K0127. A.N.W. was partially funded by STFC grant ST/N000609/1.System-scale magnetohydrodynamic (MHD) waves within Earth?s magnetosphere are often understood theoretically using box models. While these have been highly instructive in understanding many fundamental features of the various wave modes present, they neglect the complexities of geospace such as the inhomogeneities and curvilinear geometries present. Here we show global MHD simulations of resonant waves impulsively-excited by a solar wind pressure pulse. Although many aspects of the surface, fast magnetosonic (cavity/waveguide), and Alfvén modes present agree with the box and axially symmetric dipole models, we find some predictions for large-scale waves are significantly altered in a realistic magnetosphere. The radial ordering of fast mode turning points and Alfvén resonant locations may be reversed even with monotonic wave speeds. Additional nodes along field lines that are not present in the displacement/velocity occur in both the perpendicular and compressional components of the magnetic field. Close to the magnetopause the perpendicular oscillations of the magnetic field have the opposite handedness to the velocity. Finally, widely-used detection techniques for standing waves, both across and along the field, can fail to identify their presence. We explain how all these features arise from the MHD equations when accounting for a non-uniform background field and propose modified methods which might be applied to spacecraft observations.Publisher PDFPeer reviewe

Antimicrobial resistance in rural settings in Latin America: a scoping review with a One Health lens

Antimicrobial resistance (AMR) in rural Latin America is not fully understood. The transmission pathways are partially known since research predominantly focuses on the urban hospital setting. The contribution to AMR from environmental factors is usually only mentioned in large-scale animal production. To understand the state of the literature on AMR in rural LA, we carried out a scoping review using the One Health (OH) perspective. OH recognises the concomitant contributions and interconnectedness of humans, animal, and the environment, thus, we used the OH perspective to select those articles adopting a holistic view of the problem. We searched original articles in English, Spanish, and Portuguese in four peer-reviewed databases and included 21 publications in the analysis. We charted data on bibliometrics, design, data collection sources, and instruments. We identified the human, animal, and environmental contributions to AMR in rural locations, and information gaps on AMR transmission routes and AMR drivers. Intensive and non-intensive animal production systems and agricultural practices were the most frequently found human contributions to AMR. Poultry, swine, cattle, and fish were the most frequent livestock mentioned as sources of AMR bacteria. Animal carriage and/or transfer of AMR determinants or bacteria was recognised as the primary contribution of livestock to the problem, while water, soil, and farming were predominant environmental contributions. We found that only 1 article out of 21 considered the OH approach as a framework for their sampling scheme, whereas 5 out 21 discussed all the three OH components. There were hardly any descriptions of humans or human waste as reservoirs for AMR in rural locations, and rural health centres or hospitals and wildlife were not represented. No studies identified mining as an anthropogenic activity driving AMR. More OH-oriented studies, with emphasis on molecular approaches-for identification and comparison of AMR genes-are sorely needed to understand better the existence of a network of interconnected transmission routes in rural Latin America and provide efficient strategies to prevent further AMR emergence

Comparison of next-generation portable pollution monitors to measure exposure to PM2.5 from household air pollution in Puno, Peru.

Assessment of personal exposure to PM2.5 is critical for understanding intervention effectiveness and exposure-response relationships in household air pollution studies. In this pilot study, we compared PM2.5 concentrations obtained from two next-generation personal exposure monitors (the Enhanced Children MicroPEM or ECM; and the Ultrasonic Personal Air Sampler or UPAS) to those obtained with a traditional Triplex Cyclone and SKC Air Pump (a gravimetric cyclone/pump sampler). We co-located cyclone/pumps with an ECM and UPAS to obtain 24-hour kitchen concentrations and personal exposure measurements. We measured Spearmen correlations and evaluated agreement using the Bland-Altman method. We obtained 215 filters from 72 ECM and 71 UPAS co-locations. Overall, the ECM and the UPAS had similar correlation (ECM ρ = 0.91 vs UPAS ρ = 0.88) and agreement (ECM mean difference of 121.7 µg/m3 vs UPAS mean difference of 93.9 µg/m3 ) with overlapping confidence intervals when compared against the cyclone/pump. When adjusted for the limit of detection, agreement between the devices and the cyclone/pump was also similar for all samples (ECM mean difference of 68.8 µg/m3 vs UPAS mean difference of 65.4 µg/m3 ) and personal exposure samples (ECM mean difference of -3.8 µg/m3 vs UPAS mean difference of -12.9 µg/m3 ). Both the ECM and UPAS produced comparable measurements when compared against a cyclone/pump setup

On the storm‐time evolution of relativistic electron phase space density in Earth's outer radiation belt

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/98813/1/jgra50151.pd

Whole-genome characterisation of ESBL-producing E. coli isolated from drinking water and dog faeces from rural Andean households in Peru

E. coli that produce extended-spectrum beta-lactamases (ESBLs) are major multidrug-resistant bacteria. In Peru, only a few reports have characterised the whole genome of ESBL enterobacteria. We aimed to confirm the identity and antimicrobial resistance (AMR) profile of two ESBL isolates from dog faeces and drinking water of rural Andean households and determine serotype, phylogroup, sequence type (ST)/clonal complex (CC), pathogenicity, virulence genes, ESBL genes, and their plasmids. To confirm the identity and AMR profiles, we used the VITEK((R))2 system. Whole-genome sequencing (WGS) and bioinformatics analysis were performed subsequently. Both isolates were identified as E. coli, with serotypes -:H46 and O9:H10, phylogroups E and A, and ST/CC 5259/- and 227/10, respectively. The isolates were ESBL-producing, carbapenem-resistant, and not harbouring carbapenemase-encoding genes. Isolate 1143 ST5259 harboured the astA gene, encoding the EAST1 heat-stable toxin. Both genomes carried ESBL genes (blaEC-15, blaCTX-M-8, and blaCTX-M-55). Nine plasmids were detected, namely IncR, IncFIC(FII), IncI, IncFIB(AP001918), Col(pHAD28), IncFII, IncFII(pHN7A8), IncI1, and IncFIB(AP001918). Finding these potentially pathogenic bacteria is worrisome given their sources and highlights the importance of One-Health research efforts in remote Andean communities

Simultaneous traveling convection vortex events and Pc1 wave bursts at cusp latitudes observed in Arctic Canada and Svalbard

Traveling convection vortices (TCVs), which appear in ground magnetometer records at near‐cusp latitudes as solitary ~5 mHz pulses, are a signature of dynamical processes in the ion foreshock upstream of the Earth's bow shock that can stimulate transient compressions of the dayside magnetosphere. These compressions can also increase the growth rate of electromagnetic ion cyclotron (EMIC) waves, which appear in ground records at these same latitudes as bursts of Pc1 pulsations. In this study we have identified TCVs and simultaneous Pc1 burst events in two regions, Eastern Arctic Canada and Svalbard, using a combination of fluxgate magnetometers and search coil magnetometers in each region. By looking for the presence of TCVs and Pc1 bursts in two different sequences, we have found that the distribution of Pc1 bursts was more tightly clustered near local noon than that of TCV events, that neither TCVs nor Pc1 bursts were always associated with the other, and even when they occurred simultaneously their amplitudes showed little correlation. Magnetometer data from GOES‐12 were also used to characterize the strength of the magnetic compressions at geosynchronous orbit near the magnetic equator. Compressions > 2 nT at GOES‐12 occurred during 57% of the Canadian TCV events, but during ~85% of the simultaneous TCV/Pc1 burst events. There was again little evident correlation between TCV and GOES‐12 compression amplitudes. We have also documented unusually low EMIC wave activity during this deep solar minimum interval, and we attribute the low occurrence percentage of combined events in this study to this minimum. Key Points TCVs and Pc1 bursts often occur together in high‐latitude magnetometer data Pc1 events were more tightly clustered near local noon than TCV events Pc1 activity was unusually low during the solar activity minimum in 2008–2010.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/101826/1/jgra50604.pd

Antimicrobial resistance in humans, animals, water and household environs in rural Andean Peru: exploring dissemination pathways through the One Health lens

Antimicrobial resistance (AMR) is a global public health threat, especially for low and middle-income countries (LMIC) where the threat has not been fully identified. Our study aims to describe E. coli AMR in rural communities to expand our knowledge on AMR bacterial contamination. Specifically, we aim to identify and describe potential dissemination routes of AMR-carrying bacteria in humans (children's stools), community water sources (reservoirs and household sources), household environments (yard soil) and domestic animals of subsistence farmers in rural Andean areas. Our cross-sectional study was conducted in rural households in the region of Cajamarca, Peru. A total of 266 samples were collected. Thirty-four point six percent of reservoir water and 45% of household water source samples were positive for thermotolerant coliforms. Of the reservoir water samples, 92.8% were positive for E. coli, and 30.8% displayed resistance to at least one antibiotic, with the highest resistance to tetracycline. E. coli was found in 57.1% of the household water sources, 18.6% of these isolates were multidrug-resistant, and displayed the highest resistance to tetracycline (31.3%). Among samples from the children's drinking water source, 32.5% were positive for thermotolerant coliforms, and 57.1% of them were E. coli. One third of E. coli isolates were multidrug-resistant and displayed the highest AMR to tetracycline (41.6%) and ampicillin (25%). Thermotolerant coliforms were found in all the soil samples, 43.3% of the isolates were positive for E. coli, 34.3% of the E. coli isolates displayed AMR to at least one antibiotic, and displayed the highest AMR to tetracycline (25.7%). We determined thermotolerant coliforms in 97.5% of the child feces samples; 45.3% of them were E. coli, 15.9% displayed multidrug resistance, and displayed the highest resistance to ampicillin (34.1%). We identified thermotolerant coliforms in 67.5% of the animal feces samples. Of those, 38.7% were E. coli, and 37.7% were resistant to at least one antibiotic. For all the samples, the prevalence of resistance to at least one antibiotic in the E. coli and Klebsiella spp. isolates was almost 43% and the prevalence of MDR in the same isolates was nearly 9%, yet the latter nearly doubled (15.9%) in children's stools. Our results provide preliminary evidence for critical pathways and the interconnectedness of animal, human and environmental transmission but molecular analysis is needed to track dissemination routes properly

A "cookbook" for vulnerability research

There is a growing need to facilitate the interdisciplinary study of the relationship between the environment and human health and well-being. It is increasingly recognized that vulnerability is a key construct allowing discipline-specific research questions on these topics to be meaningfully contextualized. However, there is little consensus regarding the meaning of the concept of vulnerability or how it can best be utilized in research studies. In this perspective article, we use the metaphor of a "cookbook" to review promising trends in vulnerability research and to make this body of research accessible to a multi-disciplinary audience. Specifically, we discuss a selection of "recipes" (theoretical frameworks), "ingredients" (vulnerability domains), "cooking tools" (qualitative and quantitative methods), and approaches to "meal presentation" (communication of results) drawn from vulnerability studies published in the past 15 years. Our aim is for this short "cookbook" to serve as a jumping-off point for scholars unfamiliar with the vulnerability literature and an inspiration for scholars more familiar with this topic to develop new ways to navigate the tension between locally-specific assessments of vulnerability and attempts at standardization. Our ultimate take-home message is that the specifics theories and methods used in vulnerability research are less important than attention to what we see as the 3 'T's of transparency, triangulation, and transferability, and to efforts to make vulnerability research both "place-based" and comparable

Silk fibroin microparticles as carriers for delivery of human recombinant bone morphogenetic protein-2 : in vitro and in vivo bioactivity

The in vitro and in vivo efficiency of fibroin microparticles as a delivery carrier for bone morphogenetic protein-2 (BMP-2) was evaluated. BMP-2 was encapsulated in silk fibroin particles that were produced by a simple and very mild processing method. The dose-response of BMP-2-loaded fibroin particles was examined in C2C12 cells, after 5 days of culture. The BMP-2 retained most of its activity as observed by the increase in alkaline phosphatase activity, which was much higher when BMP-2 was encapsulated into the particles rather than just surface-adsorbed. After 2 weeks of culture, increased mineralization was observed with BMP-2-loaded particles in comparison to soluble added growth factor. No significant cytotoxicity was detected. When implanted in a rat ectopic model, bone formation was observed by in vivo micro-computed tomography after 2 and 4 weeks postimplantation, with particles loaded with 5 or 12.5 microg BMP-2. An increase in bone density was observed over time. Histology revealed further evidence of ectopic bone formation, observed by strong alizarin red staining and osteocalcin immunostaining. Our findings show that fibroin microparticles may present an interesting option for future clinical applications in the bone tissue engineering field, and therefore, further studies have been planned.The authors acknowledge Anna Hofmann and Anna Khadem for additional help with some experiments, and Karin Brenner for animal maintenance. This work was supported by Fundacao para a Ciencia e Tecnologia (Ph.D. grant SFRH/BD/17049/2004), project ElastM (POCI/CTM/57177/2004 funded by FEDER and the Fundacao para a Ciencia e Tecnologia), Marie Curie Alea Jacta EST short-term grant (MEST-CT-2004-8104), and European STREP Project HIP-POCRATES (NMP3-CT-2003-505758). This work was carried out under the scope of the European NoE EXPERTISSUES (NMP3-CT-2004-500283)