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1.
Space Sci Rev ; 219(5): 37, 2023.
Article in English | MEDLINE | ID: mdl-37448777

ABSTRACT

We review comprehensive observations of electromagnetic ion cyclotron (EMIC) wave-driven energetic electron precipitation using data collected by the energetic electron detector on the Electron Losses and Fields InvestigatioN (ELFIN) mission, two polar-orbiting low-altitude spinning CubeSats, measuring 50-5000 keV electrons with good pitch-angle and energy resolution. EMIC wave-driven precipitation exhibits a distinct signature in energy-spectrograms of the precipitating-to-trapped flux ratio: peaks at >0.5 MeV which are abrupt (bursty) (lasting ∼17 s, or ΔL∼0.56) with significant substructure (occasionally down to sub-second timescale). We attribute the bursty nature of the precipitation to the spatial extent and structuredness of the wave field at the equator. Multiple ELFIN passes over the same MLT sector allow us to study the spatial and temporal evolution of the EMIC wave - electron interaction region. Case studies employing conjugate ground-based or equatorial observations of the EMIC waves reveal that the energy of moderate and strong precipitation at ELFIN approximately agrees with theoretical expectations for cyclotron resonant interactions in a cold plasma. Using multiple years of ELFIN data uniformly distributed in local time, we assemble a statistical database of ∼50 events of strong EMIC wave-driven precipitation. Most reside at L∼5-7 at dusk, while a smaller subset exists at L∼8-12 at post-midnight. The energies of the peak-precipitation ratio and of the half-peak precipitation ratio (our proxy for the minimum resonance energy) exhibit an L-shell dependence in good agreement with theoretical estimates based on prior statistical observations of EMIC wave power spectra. The precipitation ratio's spectral shape for the most intense events has an exponential falloff away from the peak (i.e., on either side of ∼1.45 MeV). It too agrees well with quasi-linear diffusion theory based on prior statistics of wave spectra. It should be noted though that this diffusive treatment likely includes effects from nonlinear resonant interactions (especially at high energies) and nonresonant effects from sharp wave packet edges (at low energies). Sub-MeV electron precipitation observed concurrently with strong EMIC wave-driven >1 MeV precipitation has a spectral shape that is consistent with efficient pitch-angle scattering down to ∼ 200-300 keV by much less intense higher frequency EMIC waves at dusk (where such waves are most frequent). At ∼100 keV, whistler-mode chorus may be implicated in concurrent precipitation. These results confirm the critical role of EMIC waves in driving relativistic electron losses. Nonlinear effects may abound and require further investigation.

2.
Space Sci Rev ; 216(5): 103, 2020.
Article in English | MEDLINE | ID: mdl-32831412

ABSTRACT

The Electron Loss and Fields Investigation with a Spatio-Temporal Ambiguity-Resolving option (ELFIN-STAR, or heretoforth simply: ELFIN) mission comprises two identical 3-Unit (3U) CubeSats on a polar (∼93∘ inclination), nearly circular, low-Earth (∼450 km altitude) orbit. Launched on September 15, 2018, ELFIN is expected to have a >2.5 year lifetime. Its primary science objective is to resolve the mechanism of storm-time relativistic electron precipitation, for which electromagnetic ion cyclotron (EMIC) waves are a prime candidate. From its ionospheric vantage point, ELFIN uses its unique pitch-angle-resolving capability to determine whether measured relativistic electron pitch-angle and energy spectra within the loss cone bear the characteristic signatures of scattering by EMIC waves or whether such scattering may be due to other processes. Pairing identical ELFIN satellites with slowly-variable along-track separation allows disambiguation of spatial and temporal evolution of the precipitation over minutes-to-tens-of-minutes timescales, faster than the orbit period of a single low-altitude satellite (Torbit ∼ 90 min). Each satellite carries an energetic particle detector for electrons (EPDE) that measures 50 keV to 5 MeV electrons with Δ E/E < 40% and a fluxgate magnetometer (FGM) on a ∼72 cm boom that measures magnetic field waves (e.g., EMIC waves) in the range from DC to 5 Hz Nyquist (nominally) with <0.3 nT/sqrt(Hz) noise at 1 Hz. The spinning satellites (Tspin ∼ 3 s) are equipped with magnetorquers (air coils) that permit spin-up or -down and reorientation maneuvers. Using those, the spin axis is placed normal to the orbit plane (nominally), allowing full pitch-angle resolution twice per spin. An energetic particle detector for ions (EPDI) measures 250 keV - 5 MeV ions, addressing secondary science. Funded initially by CalSpace and the University Nanosat Program, ELFIN was selected for flight with joint support from NSF and NASA between 2014 and 2018 and launched by the ELaNa XVIII program on a Delta II rocket (with IceSatII as the primary). Mission operations are currently funded by NASA. Working under experienced UCLA mentors, with advice from The Aerospace Corporation and NASA personnel, more than 250 undergraduates have matured the ELFIN implementation strategy; developed the instruments, satellite, and ground systems and operate the two satellites. ELFIN's already high potential for cutting-edge science return is compounded by concurrent equatorial Heliophysics missions (THEMIS, Arase, Van Allen Probes, MMS) and ground stations. ELFIN's integrated data analysis approach, rapid dissemination strategies via the SPace Environment Data Analysis System (SPEDAS), and data coordination with the Heliophysics/Geospace System Observatory (H/GSO) optimize science yield, enabling the widest community benefits. Several storm-time events have already been captured and are presented herein to demonstrate ELFIN's data analysis methods and potential. These form the basis of on-going studies to resolve the primary mission science objective. Broad energy precipitation events, precipitation bands, and microbursts, clearly seen both at dawn and dusk, extend from tens of keV to >1 MeV. This broad energy range of precipitation indicates that multiple waves are providing scattering concurrently. Many observed events show significant backscattered fluxes, which in the past were hard to resolve by equatorial spacecraft or non-pitch-angle-resolving ionospheric missions. These observations suggest that the ionosphere plays a significant role in modifying magnetospheric electron fluxes and wave-particle interactions. Routine data captures starting in February 2020 and lasting for at least another year, approximately the remainder of the mission lifetime, are expected to provide a very rich dataset to address questions even beyond the primary mission science objective.

3.
Space Sci Rev ; 215(1): 9, 2019.
Article in English | MEDLINE | ID: mdl-30880847

ABSTRACT

With the advent of the Heliophysics/Geospace System Observatory (H/GSO), a complement of multi-spacecraft missions and ground-based observatories to study the space environment, data retrieval, analysis, and visualization of space physics data can be daunting. The Space Physics Environment Data Analysis System (SPEDAS), a grass-roots software development platform (www.spedas.org), is now officially supported by NASA Heliophysics as part of its data environment infrastructure. It serves more than a dozen space missions and ground observatories and can integrate the full complement of past and upcoming space physics missions with minimal resources, following clear, simple, and well-proven guidelines. Free, modular and configurable to the needs of individual missions, it works in both command-line (ideal for experienced users) and Graphical User Interface (GUI) mode (reducing the learning curve for first-time users). Both options have "crib-sheets," user-command sequences in ASCII format that can facilitate record-and-repeat actions, especially for complex operations and plotting. Crib-sheets enhance scientific interactions, as users can move rapidly and accurately from exchanges of technical information on data processing to efficient discussions regarding data interpretation and science. SPEDAS can readily query and ingest all International Solar Terrestrial Physics (ISTP)-compatible products from the Space Physics Data Facility (SPDF), enabling access to a vast collection of historic and current mission data. The planned incorporation of Heliophysics Application Programmer's Interface (HAPI) standards will facilitate data ingestion from distributed datasets that adhere to these standards. Although SPEDAS is currently Interactive Data Language (IDL)-based (and interfaces to Java-based tools such as Autoplot), efforts are under-way to expand it further to work with python (first as an interface tool and potentially even receiving an under-the-hood replacement). We review the SPEDAS development history, goals, and current implementation. We explain its "modes of use" with examples geared for users and outline its technical implementation and requirements with software developers in mind. We also describe SPEDAS personnel and software management, interfaces with other organizations, resources and support structure available to the community, and future development plans. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s11214-018-0576-4) contains supplementary material, which is available to authorized users.

4.
Insect Mol Biol ; 18(3): 383-93, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19523070

ABSTRACT

Culicoides spp. are vectors of several infectious diseases of veterinary importance and a major cause of allergy in horses and other livestock. Their saliva contains a number of proteins which enable blood feeding, enhance disease transmission and act as allergens. We report the construction of a novel cDNA library from Culicoides nubeculosus linked to the analysis of abundant salivary gland proteins by mass spectrometry. Fifty-four novel proteins sequences are described including those of the enzymes maltase, hyaluronidase and two serine proteases demonstrated to be present in Culicoides salivary glands, as well as several members of the D7 family and protease inhibitors with putative anticoagulant activity. In addition, several families of abundant proteins with unknown function were identified including some of the major candidate allergens that cause insect bite hypersensitivity in horses.


Subject(s)
Ceratopogonidae/genetics , Insect Proteins/genetics , Salivary Proteins and Peptides/genetics , Amino Acid Sequence , Animals , Ceratopogonidae/metabolism , Gene Library , Insect Proteins/metabolism , Mass Spectrometry , Molecular Sequence Data , Proteome , Salivary Glands/metabolism , Salivary Proteins and Peptides/metabolism
5.
Vet Immunol Immunopathol ; 122(1-2): 94-103, 2008 Mar 15.
Article in English | MEDLINE | ID: mdl-18068808

ABSTRACT

IgE-mediated type 1 hypersensitivity reactions to the bites of insects are a common cause of skin disease in horses. Insect bite hypersensitivity (IBH) is most frequently associated with bites of Culicoides spp. and occurs in all parts of the world where horses and Culicoides coexist. The main allergens that cause IBH are probably some of the abundant proteins in the saliva of Culicoides associated with blood feeding. Western blots of Culicoides proteins separated by 1D gel-electrophoresis detected strong IgE responses in all horses with IBH to antigens in protein extracts from wild caught Culicoides, but only weak responses to salivary antigens from captive bred C. nubeculosus which may reflect important differences among allergens from different species of Culicoides or differences between thorax and salivary gland antigens. 2D electrophoresis and mass spectrometry were used to identify several of the abundant proteins in the saliva of C. nubeculosus. These included maltase, members of the D7 family, and several small, basic proteins associated with blood feeding. The most frequently detected IgE-binding proteins were in a group of proteins with pI>8.5 and mass 40-50kDa. Mass spectrometry identified two of these allergenic proteins as similar to hyaluronidase and a heavily glycosylated protein of unknown function that have previously been identified in salivary glands of C. sonorensis.


Subject(s)
Allergens/analysis , Ceratopogonidae/immunology , Horse Diseases/immunology , Insect Bites and Stings/veterinary , Insect Proteins/analysis , Salivary Glands/immunology , Amino Acid Sequence , Animals , Blotting, Western , Ceratopogonidae/chemistry , Horses , Immunoglobulin E/blood , Insect Bites and Stings/immunology , Insect Proteins/chemistry , Molecular Sequence Data , Salivary Glands/chemistry
6.
Prog Transplant ; 10(3): 169-76, 2000 Sep.
Article in English | MEDLINE | ID: mdl-11216276

ABSTRACT

Increasing demands are being placed on transplant nurse coordinators for more precise documentation of their teaching of kidney transplant patients, but the amount of time nurses have for this added documentation remains unchanged or has diminished. After a thorough review of the literature, our transplant team found no patient teaching documentation format that assisted us in overcoming the problem of increased demands. Consequently, following the Joint Commission on Accreditation of Healthcare Organization standards, we developed a Renal Transplant Patient Teaching Record that has assisted our team in documenting the pre- and post-transplant patient teaching that we complete.


Subject(s)
Documentation/methods , Kidney Transplantation/nursing , Patient Education as Topic/methods , Perioperative Nursing/methods , Humans , Kidney Transplantation/psychology , Nursing Records
7.
Clin Nurse Spec ; 13(3): 119-22, 1999 May.
Article in English | MEDLINE | ID: mdl-10531834

ABSTRACT

The purpose of this study was to discover whether implementation of a patient-family pathway with patients and families undergoing coronary artery bypass graft (CABG) surgery impacted anxiety, information with care planning, and patient length of stay. Using an experimental design, a sample of 60 patients and family members was studied. Each patient and his or her designated family member received either the patient-family pathway or the hospital's standard care planning. Findings indicated no statistically significant differences in state anxiety or information with care planning between patients and family members receiving the patient-family pathway and those receiving standard care planning. There was no statistically significant difference in length of stay between the two patient groups. The results indicate that the CABG patient-family pathway has limited value to patients and families as measured in this study. Resources can be real-located to other uses that may have a more positive impact on the patient and family experience.


Subject(s)
Coronary Artery Bypass/nursing , Critical Pathways/organization & administration , Family/psychology , Nurse Clinicians/organization & administration , Patient Education as Topic/organization & administration , Professional-Family Relations , Adult , Aged , Coronary Artery Bypass/psychology , Female , Humans , Male , Middle Aged , Nurse Clinicians/psychology , Nursing Staff, Hospital/organization & administration , Nursing Staff, Hospital/psychology , Program Development , Program Evaluation
8.
J Nurs Adm ; 28(7-8): 32-8, 1998.
Article in English | MEDLINE | ID: mdl-9709694

ABSTRACT

With the use of restraints to manage difficult patients becoming routine, one hospital initiated strategies to reduce restraint use. The authors describe the development and implementation of a restraint reduction program, educational strategies, and the evaluation program. The program is successfully reducing the prevalence of restraint use.


Subject(s)
Geriatric Nursing/standards , Nursing Staff, Hospital/standards , Restraint, Physical , Aged , Female , Hospital Bed Capacity, 300 to 499 , Hospitals, University , Humans , Inservice Training/organization & administration , Joint Commission on Accreditation of Healthcare Organizations , Male , Missouri , Nursing Staff, Hospital/education , Program Evaluation , Quality Assurance, Health Care , Restraint, Physical/adverse effects , Risk Factors
9.
J Nurs Adm ; 27(11): 23-6, 1997 Nov.
Article in English | MEDLINE | ID: mdl-9372804

ABSTRACT

Palliative Care Teams (PCTs) could be an answer for providing care for the hopelessly ill patient without accumulating high costs. The authors discuss their examination of the relationship between the implementation of a PCT and patient charges. Data indicated that daily charges were reduced significantly after the implementation a PCT.


Subject(s)
Hospital Charges , Palliative Care/economics , Patient Care Team/economics , Terminal Care/economics , Adult , Aged , Aged, 80 and over , Female , Hospitals, University , Humans , Male , Middle Aged , Missouri , Palliative Care/organization & administration , Terminal Care/organization & administration
10.
J Comp Psychol ; 111(2): 185-93, 1997 Jun.
Article in English | MEDLINE | ID: mdl-9170283

ABSTRACT

Social referencing is the seeking of information from another individual and the use of that information to evaluate a situation. It is a well-documented ability in human infants but has not been studied experimentally in nonhuman primates. Seventeen young nursery-reared chimpanzees (14 to 41 months old) were observed in a standard social referencing paradigm in which they received happy and fear messages concerning novel objects from a familiar human caregiver. Each chimpanzee looked referentially at their caregiver, and the emotional messages that they received differentially influenced their gaze behavior and avoidance of the novel objects. It is concluded that chimpanzees can acquire information about their complex social and physical environments through social referencing and can use emotional information to alter their own behavior.


Subject(s)
Aging/psychology , Imitative Behavior , Pan troglodytes/psychology , Problem Solving , Social Behavior , Social Conformity , Animals , Attention , Avoidance Learning , Emotions , Female , Humans , Male
11.
J Nurs Care Qual ; 11(3): 62-7, 1997 Feb.
Article in English | MEDLINE | ID: mdl-9029855

ABSTRACT

Nurse practitioners in ambulatory care settings must begin using quality improvement strategies to enhance patient outcomes and to improve patient follow-up. The article highlights the development and beginning stages of implementation of one such quality improvement program and discusses the actions that were taken to increase timeliness of key patient processes. An example of a quality improvement educational program, outlines of the plan, and scope of services are also provided.


Subject(s)
Ambulatory Care/standards , Continuity of Patient Care , Quality Assurance, Health Care , Humans , Nurse Practitioners , Program Evaluation
12.
Subst Use Misuse ; 32(2): 149-68, 1997 Jan.
Article in English | MEDLINE | ID: mdl-9044544

ABSTRACT

Understanding the effects of substance misuse by pregnant women and mothers of young children requires a knowledge of the epidemiology of women's drug and alcohol use and misuse, the treatment of pregnant and postpartum chemically dependent women, the impact of prenatal exposure on the offspring outcome and later development, and, finally, methodological issues related to these fields. This bibliography provides a list of recent and classic articles in these areas as well as information about the research in these areas.


Subject(s)
Infant, Newborn, Diseases/chemically induced , Maternal Exposure/adverse effects , Maternal Welfare , Pregnancy Complications/epidemiology , Pregnancy Complications/therapy , Research Design , Substance-Related Disorders/epidemiology , Substance-Related Disorders/therapy , Female , Humans , Infant, Newborn , Pregnancy
13.
Plast Reconstr Surg ; 80(6): 769-74, 1987 Dec.
Article in English | MEDLINE | ID: mdl-2960996

ABSTRACT

Medial orbital wall fenestrations were created bilaterally in 16 adult cats. The fenestrations were reconstructed with polyglactin 910 film, Dacron-reinforced silicone sheeting, or no implant. Polyglactin 910 was found to be well tolerated in this traumatized area of paranasal sinus bone and soft tissue and was totally absorbed in 4 months. Dacron-reinforced silicone sheeting induced a long-standing acute inflammatory reaction in a similar milieu. Partial osseus replacement of the orbital fenestrations occurred in all animals, but it was accompanied by distortion and erosion in apposition to the silicone sheeting. The study does not answer the question of whether orbital contour will be maintained on a long-term basis adjacent to a pneumatized sinus following reconstruction with a bioabsorbable implant.


Subject(s)
Orbital Fractures/surgery , Polyglactin 910 , Polymers , Prostheses and Implants , Skull Fractures/surgery , Animals , Biocompatible Materials , Cats , Disease Models, Animal , Inflammation , Orbital Fractures/pathology , Polyethylene Terephthalates , Silicones
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