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1.
ATS Sch ; 5(1): 19-31, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38628297

RESUMO

Pediatric pulmonology fellowship training programs are required by the Accreditation Council for Graduate Medical Education to report Pediatric Subspecialty Milestones biannually to track fellow progress. However, several issues, such as lack of subspecialty-specific context and ambiguous language, have raised concerns about their validity and applicability to use for fellow assessment and curriculum development. In this Perspective, we briefly share the process of the Pediatric Pulmonology Milestones 2.0 Work Group in creating new specialty-specific Milestones and tailoring information on the Harmonized Milestones to pediatric pulmonologists, with the goal of improving the Milestones' utility for stakeholders, including pulmonology fellows, faculty, program directors, and accrediting bodies. In addition, we created a supplemental guide to better link the Milestones to pulmonary-specific scenarios to create a shared mental model between stakeholders and remove a potential detriment to validity. Through the process, a number of guiding principles were clarified, including: 1) every Milestone should be able to be assessed independently, without overlap with other Milestones; 2) there should be clear developmental progression from one Milestone to the next; 3) Milestones should be based on the unique skills expected of pediatric pulmonologists; and 4) health equity should be a core component to highlight as a top priority to all stakeholders. In this Perspective, we describe these principles that guided formulation of the Pediatric Pulmonary Milestones to help familiarize the pediatric pulmonary community with the new Milestones. In addition, we share lessons learned and challenges in our process to inform other specialties that may soon participate in this process.

2.
Pediatr Ann ; 52(4): e153-e158, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37036771

RESUMO

Asthma is one of the most common chronic diseases affecting the pediatric population. The diagnosis and management of asthma is constantly evolving, and recently the National Heart, Lung, and Blood Institute published an updated guideline regarding various aspects of pediatric asthma. In this report, we review and summarize these guidelines and compare them with the Global Initiative for Asthma guidelines. [Pediatr Ann. 2023;52(4):e153-e158.].


Assuntos
Antiasmáticos , Asma , Humanos , Criança , Asma/diagnóstico , Asma/prevenção & controle
3.
Nat Commun ; 13(1): 6259, 2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36307443

RESUMO

Electromagnetic whistler-mode waves in space plasmas play critical roles in collisionless energy transfer between the electrons and the electromagnetic field. Although resonant interactions have been considered as the likely generation process of the waves, observational identification has been extremely difficult due to the short time scale of resonant electron dynamics. Here we show strong nongyrotropy, which rotate with the wave, of cyclotron resonant electrons as direct evidence for the locally ongoing secular energy transfer from the resonant electrons to the whistler-mode waves using ultra-high temporal resolution data obtained by NASA's Magnetospheric Multiscale (MMS) mission in the magnetosheath. The nongyrotropic electrons carry a resonant current, which is the energy source of the wave as predicted by the nonlinear wave growth theory. This result proves the nonlinear wave growth theory, and furthermore demonstrates that the degree of nongyrotropy, which cannot be predicted even by that nonlinear theory, can be studied by observations.

4.
J Geophys Res Space Phys ; 127(7): e2022JA030408, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36248013

RESUMO

We present observations in Earth's magnetotail by the Magnetospheric Multiscale spacecraft that are consistent with magnetic field annihilation, rather than magnetic topology change, causing fast magnetic-to-electron energy conversion in an electron-scale current sheet. Multi-spacecraft analysis for the magnetic field reconstruction shows that an electron-scale magnetic island was embedded in the observed electron diffusion region (EDR), suggesting an elongated shape of the EDR. Evidence for the annihilation was revealed in the form of the island growing at a rate much lower than expected for the standard X-type geometry of the EDR, which indicates that magnetic flux injected into the EDR was not ejected from the X-point or accumulated in the island, but was dissipated in the EDR. This energy conversion process is in contrast to that in the standard EDR of a reconnecting current sheet where the energy of antiparallel magnetic fields is mostly converted to electron bulk-flow energy. Fully kinetic simulation also demonstrates that an elongated EDR is subject to the formation of electron-scale magnetic islands in which fast but transient annihilation can occur. Consistent with the observations and simulation, theoretical analysis shows that fast magnetic diffusion can occur in an elongated EDR in the presence of nongyrotropic electron effects. We suggest that the annihilation in elongated EDRs may contribute to the dissipation of magnetic energy in a turbulent collisionless plasma.

5.
J Geophys Res Space Phys ; 126(4): e2020JA028922, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33868890

RESUMO

Electromagnetic ion cyclotron (EMIC) waves play important roles in particle loss processes in the magnetosphere. Determining the evolution of EMIC waves as they propagate and how this evolution affects wave-particle interactions requires accurate knowledge of the wave vector, k. We present a technique using the curl of the wave magnetic field to determine k observationally, enabled by the unique configuration and instrumentation of the Magnetospheric MultiScale (MMS) spacecraft. The wave curl analysis is demonstrated for synthetic arbitrary electromagnetic waves with varying properties typical of observed EMIC waves. The method is also applied to an EMIC wave interval observed by MMS on October 28, 2015. The derived wave properties and k from the wave curl analysis for the observed EMIC wave are compared with the Waves in Homogenous, Anisotropic, Multi-component Plasma (WHAMP) wave dispersion solution and with results from other single- and multi-spacecraft techniques. We find good agreement between k from the wave curl analysis, k determined from other observational techniques, and k determined from WHAMP. Additionally, the variation of k due to the time and frequency intervals used in the wave curl analysis is explored. This exploration demonstrates that the method is robust when applied to a wave containing at least 3-4 wave periods and over a rather wide frequency range encompassing the peak wave emission. These results provide confidence that we are able to directly determine the wave vector properties using this multi-spacecraft method implementation, enabling systematic studies of EMIC wave k properties with MMS.

6.
J Environ Manage ; 288: 112451, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33827023

RESUMO

The shift of discussions on wastewater management to realize a circular water economy requires rethinking of how the existing systems are managed. The collection system, a physical infrastructure that collects and transports wastewater, is often overlooked in innovation studies in wastewater management. Hence, a review of the collection system is required to realize overlooked innovation points, especially those of its functions and configurations. In this paper, we highlight the possibility of the collection system to contribute to wastewater management, not only to collect and transport wastewater, but to treat wastewater through enhancing sewer self-purification. To realize this, a systems analysis of the forms and functions of the collection system was first conducted to see how the collection system supports different wastewater management systems. It was found that emphasis on the collection system's function to treat wastewater is beneficial because of the transition of wastewater management towards a circular water economy. Second, a scenario analysis of applying enhanced sewer self-purification technologies was conducted to determine communities which would most benefit from using the collection system to treat wastewater. The findings highlight that communities with as much as 100 cap ha-1, typical of urban peripheries, could have their pollutant load reduced to about half if the pipe length per capita is 5 m. It was seen in this study that while the collection system supports wastewater management by functioning to collect and transport wastewater, it can further be elevated into a treatment technology within appropriate localities and thus, contribute to a circular water economy.


Assuntos
Esgotos , Águas Residuárias , Análise de Sistemas , Água
7.
Artigo em Inglês | MEDLINE | ID: mdl-33265908

RESUMO

Human health and wellbeing and the health of the biosphere are inextricably linked. The state of Earth's life-support systems, including freshwater, oceans, land, biodiversity, atmosphere, and climate, affect human health. At the same time, human activities are adversely affecting natural systems. This review paper is the outcome of an interdisciplinary workshop under the auspices of the Future Earth Health Knowledge Action Network (Health KAN). It outlines a research agenda to address cross-cutting knowledge gaps to further understanding and management of the health risks of these global environmental changes through an expert consultation and review process. The research agenda has four main themes: (1) risk identification and management (including related to water, hygiene, sanitation, and waste management); food production and consumption; oceans; and extreme weather events and climate change. (2) Strengthening climate-resilient health systems; (3) Monitoring, surveillance, and evaluation; and (4) risk communication. Research approaches need to be transdisciplinary, multi-scalar, inclusive, equitable, and broadly communicated. Promoting resilient and sustainable development are critical for achieving human and planetary health.


Assuntos
Pesquisa Interdisciplinar , Desenvolvimento Sustentável , Biodiversidade , Mudança Climática , Humanos , Oceanos e Mares
8.
J Geophys Res Space Phys ; 125(7): e2020JA027778, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32999806

RESUMO

In this study, the ion composition of flux transfer events (FTEs) observed within the magnetosheath proper is examined. These FTEs were observed just upstream of the Earth's postnoon magnetopause by the National Aeronautics and Space Administration (NASA) Magnetospheric Multiscale (MMS) spacecraft constellation. The minor ion characteristics are described using energy spectrograms, flux distributions, and ion moments as the constellation encountered each FTE. In conjunction with electron data and magnetic field observations, such observations provide important contextual information on the formation, topologies, and evolution of FTEs. In particular, minor ions, when combined with the field-aligned streaming of electrons, are reliable indicators of FTE topology. The observations are also placed (i) in context of the solar wind magnetic field configuration, (ii) the connection of the sampled flux tube to the ionosphere, and (iii) the location relative to the modeled reconnection line at the magnetopause. While protons and alpha particles were often depleted within the FTEs relative to the surrounding magnetosheath plasma, the He+ and O+ populations showed clear enhancements either near the center or near the edges of the FTE, and the bulk plasma flow directions are consistent with magnetic reconnection northward of the spacecraft and convection from the dayside toward the flank magnetopause.

9.
Nat Commun ; 11(1): 5049, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33028826

RESUMO

Magnetotail reconnection plays a crucial role in explosive energy conversion in geospace. Because of the lack of in-situ spacecraft observations, the onset mechanism of magnetotail reconnection, however, has been controversial for decades. The key question is whether magnetotail reconnection is externally driven to occur first on electron scales or spontaneously arising from an unstable configuration on ion scales. Here, we show, using spacecraft observations and particle-in-cell (PIC) simulations, that magnetotail reconnection starts from electron reconnection in the presence of a strong external driver. Our PIC simulations show that this electron reconnection then develops into ion reconnection. These results provide direct evidence for magnetotail reconnection onset caused by electron kinetics with a strong external driver.

10.
J Geophys Res Space Phys ; 125(4): e2019JA027181, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32728509

RESUMO

During the September 2015 to March 2016 duration (sometimes referred to as Phase 1A) of the Magnetospheric Multiscale Mission, the Dual Electron Spectrometers (DES) were configured to generously utilize lossy compression. While this maximized the number of velocity distribution functions downlinked, it came at the expense of lost information content for a fraction of the frames. Following this period of lossy compression, the DES was reconfigured in a way that allowed for 95% of the frames to arrive to the ground without loss. Using this high-quality set of frames from on-orbit observations, we compressed and decompressed the frames on the ground to create a side-by-side record of the compression effect. This record was used to drive an optimization method that (a) derived basis functions capable of approximating the lossless sample space and with nonnegative coefficients and (b) fitted a function which maps the lossy frames to basis weights that recreate the frame without compression artifacts. This method is introduced and evaluated in this paper. Data users should expect a higher level of confidence in the absolute scale of density/temperature measurements and notice less sinusoidal bias in the velocity X and Y components (GSE).

11.
Phys Rev Lett ; 125(2): 025103, 2020 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-32701350

RESUMO

We report measurements of lower-hybrid drift waves driving electron heating and vortical flows in an electron-scale reconnection layer under a guide field. Electrons accelerated by the electrostatic potential of the waves exhibit perpendicular and nongyrotropic heating. The vortical flows generate magnetic field perturbations comparable to the guide field magnitude. The measurements reveal a new regime of electron-wave interaction and how this interaction modifies the electron dynamics in the reconnection layer.

12.
J Geophys Res Space Phys ; 125(4): e2019JA027665, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32714734

RESUMO

On 5 May 2017, MMS observed a crater-type flux rope on the dawnside tailward magnetopause with fluctuations. The boundary-normal analysis shows that the fluctuations can be attributed to nonlinear Kelvin-Helmholtz (KH) waves. Reconnection signatures such as flow reversals and Joule dissipation were identified at the leading and trailing edges of the flux rope. In particular, strong northward electron jets observed at the trailing edge indicated midlatitude reconnection associated with the 3-D structure of the KH vortex. The scale size of the flux rope, together with reconnection signatures, strongly supports the interpretation that the flux rope was generated locally by KH vortex-induced reconnection. The center of the flux rope also displayed signatures of guide-field reconnection (out-of-plane electron jets, parallel electron heating, and Joule dissipation). These signatures indicate that an interface between two interlinked flux tubes was undergoing interaction, causing a local magnetic depression, resulting in an M-shaped crater flux rope, as supported by reconstruction.

13.
Phys Rev Lett ; 124(9): 095101, 2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-32202894

RESUMO

Electrostatic solitary wave (ESW)-a Debye-scale structure in space plasmas-was believed to accelerate electrons. However, such a belief is still unverified in spacecraft observations, because the ESW usually moves fast in spacecraft frame and its interior has never been directly explored. Here, we report the first measurements of an ESW's interior, by the Magnetospheric Multiscale mission located in a magnetotail reconnection jet. We find that this ESW has a parallel scale of 5λ_{De} (Debye length), a superslow speed (99 km/s) in spacecraft frame, a longtime duration (250 ms), and a potential drop eφ_{0}/kT_{e}∼5%. Inside the ESW, surprisingly, there is no electron acceleration, no clear change of electron distribution functions, but there exist strong electrostatic electron cyclotron waves. Our observations challenge the conventional belief that ESWs are efficient at particle acceleration.

14.
Phys Rev Lett ; 124(6): 065101, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32109113

RESUMO

The first-order Fermi acceleration of electrons requires an injection of electrons into a mildly relativistic energy range. However, the mechanism of injection has remained a puzzle both in theory and observation. We present direct evidence for a novel stochastic shock drift acceleration theory for the injection obtained with Magnetospheric Multiscale observations at the Earth's bow shock. The theoretical model can explain electron acceleration to mildly relativistic energies at high-speed astrophysical shocks, which may provide a solution to the long-standing issue of electron injection.

15.
Nat Commun ; 11(1): 141, 2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31919351

RESUMO

The Magnetospheric Multiscale (MMS) spacecraft encounter an electron diffusion region (EDR) of asymmetric magnetic reconnection at Earth's magnetopause. The EDR is characterized by agyrotropic electron velocity distributions on both sides of the neutral line. Various types of plasma waves are produced by the magnetic reconnection in and near the EDR. Here we report large-amplitude electron Bernstein waves (EBWs) at the electron-scale boundary of the Hall current reversal. The finite gyroradius effect of the outflow electrons generates the crescent-shaped agyrotropic electron distributions, which drive the EBWs. The EBWs propagate toward the central EDR. The amplitude of the EBWs is sufficiently large to thermalize and diffuse electrons around the EDR. The EBWs contribute to the cross-field diffusion of the electron-scale boundary of the Hall current reversal near the EDR.

16.
Phys Rev Lett ; 125(26): 265102, 2020 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-33449730

RESUMO

Magnetic reconnection is of fundamental importance to plasmas because of its role in releasing and repartitioning stored magnetic energy. Previous results suggest that this energy is predominantly released as ion enthalpy flux along the reconnection outflow. Using Magnetospheric Multiscale data we find the existence of very significant electron energy flux densities in the vicinity of the magnetopause electron dissipation region, orthogonal to the ion energy outflow. These may significantly impact models of electron transport, wave generation, and particle acceleration.

17.
Geophys Res Lett ; 46(12): 6287-6296, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31598018

RESUMO

While vorticity defined as the curl of the velocity has been broadly used in fluid and plasma physics, this quantity has been underutilized in space physics due to low time resolution observations. We report Magnetospheric Multiscale (MMS) observations of enhanced electron vorticity in the vicinity of the electron diffusion region of magnetic reconnection. On 11 July 2017 MMS traversed the magnetotail current sheet, observing tailward-to-earthward outflow reversal, current-carrying electron jets in the direction along the electron meandering motion or out-of-plane direction, agyrotropic electron distribution functions, and dissipative signatures. At the edge of the electron jets, the electron vorticity increased with magnitudes greater than the electron gyrofrequency. The out-of-plane velocity shear along distance from the current sheet leads to the enhanced vorticity. This, in turn, contributes to the magnetic field perturbations observed by MMS. These observations indicate that electron vorticity can act as a proxy for delineating the electron diffusion region of magnetic reconnection.

18.
Phys Rev E ; 99(4-1): 043204, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31108651

RESUMO

The electron diffusion region (EDR) is the region where magnetic reconnection is initiated and electrons are energized. Because of experimental difficulties, the structure of the EDR is still poorly understood. A key question is whether the EDR has a homogeneous or patchy structure. Here we report Magnetospheric Multiscale (MMS) spacecraft observations providing evidence of inhomogeneous current densities and energy conversion over a few electron inertial lengths within an EDR at the terrestrial magnetopause, suggesting that the EDR can be rather structured. These inhomogenenities are revealed through multipoint measurements because the spacecraft separation is comparable to a few electron inertial lengths, allowing the entire MMS tetrahedron to be within the EDR most of the time. These observations are consistent with recent high-resolution and low-noise kinetic simulations.

19.
Nature ; 569(7757): E9, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31073227

RESUMO

Change history: In this Letter, the y-axis values in Fig. 3f should go from 4 to -8 (rather than from 4 to -4), the y-axis values in Fig. 3h should appear next to the major tick marks (rather than the minor ticks), and in Fig. 1b, the arrows at the top and bottom of the electron-scale current sheet were going in the wrong direction; these errors have been corrected online.

20.
Pediatr Ann ; 48(4): 146-147, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30986312
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