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1.
Pediatr Emerg Care ; 39(11): 848-852, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36728549

RESUMO

BACKGROUND: Debriefing in the pediatric emergency department (PED) is an invaluable tool to improve team well-being, communication, and performance. Despite evidence, surveys have reported heavy workload as a barrier to debriefing leading to missed opportunities for improvement in an already busy ED. The study aims to determine the association between the incidence of debriefing after pediatric trauma resuscitations and PED crowding. METHODS: A total of 491 Trauma One activations in Riley Children's Hospital Pediatric Emergency Department that presented between April 2018 to December 2019 were included in the study. Debriefing documentations, patient demographics, time and date of presentation, mechanism of injury, injury severity score, disposition from PED, and length of stay (LOS) were collected and analyzed. The National Emergency Department Overcrowding Scale score at arrival, Average LOS, total PED census, total PED waiting room census, and rates of left without being seen were compared between groups. RESULTS: Of 491 Trauma One activations presented to our PED, 50 (10%) trauma evaluations had documented debriefing. The National Emergency Department Overcrowding Scale score at presentation was significantly lower in those with debriefing versus without debriefing. In addition, the PED hourly census, waiting room census, average LOS, and left without being seen were also significantly lower in the group with debriefing. In addition, trauma cases with debriefing had a higher proportion of patients with profound injuries and discharges to the morgue. CONCLUSIONS: Pediatric emergency department crowding is a significant barrier to debriefing after trauma resuscitations. However, profound injuries and traumatic pediatric deaths remain the strongest predictors in conducting debriefing regardless of PED crowding status.


Assuntos
Comunicação , Ressuscitação , Humanos , Criança , Tempo de Internação , Carga de Trabalho , Serviço Hospitalar de Emergência , Aglomeração , Estudos Retrospectivos
2.
Pediatr Emerg Care ; 39(1): 1-5, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36279221

RESUMO

OBJECTIVES: Widespread Haemophilus influenzae and Streptococcus pneumoniae immunization has decreased occult bacteremia and bacterial meningitis rates. Practice has evolved in pediatric emergency departments (PEDs) to favor fewer diagnostic tests for and empiric treatment of invasive bacterial infection. We lack evidence-based guidance on evaluation and treatment of unimmunized (UnI) or underimmunized (UnderI) febrile children. This study aims to determine how parental report of immunization status in febrile PED patients impacts rates of diagnostic testing, interventions, and hospital admissions. METHODS: This is a retrospective cohort study with chart review of encounters of children aged 3 to 36 months presenting to an academic, tertiary care PED in 2019 using International Classification of Diseases-10 code for fever (R50.9). Inclusion criteria were documented fever of 38°C and higher and well appearance. Encounters were excluded if there was a history of chronic illness or documentation of ill appearance or hemodynamic instability. Encounters were grouped by provider-documented immunization status. Fischer exact test and logistic regression compared rates of diagnostic testing (serum, urine or cerebrospinal fluid laboratory studies, and chest radiographs), interventions (intravenous fluid bolus, intravenous antibiotic or steroid administration, respiratory support, or breathing treatment), and hospital admissions between UnderI, UnI, and fully immunized (FI) groups. RESULTS: Of the 1813 encounters reviewed, 1093 (60%) included provider-documented immunization status and 788 (43%) met final inclusion criteria: 23 (2.1%) UnI, 44 (5.8%) UnderI, and 721 (92.1%) FI. The UnderI and UnI children experienced significantly higher rates of laboratory evaluation including complete blood count and blood culture, medical intervention, and antibiotic prescriptions while in the PED. No significant differences were observed for rates of chest radiographs, hospital admissions, or 72-hour PED return visits. CONCLUSIONS: Higher rates of laboratory testing and interventions were observed in UnderI and UnI versus FI febrile patients at a PED, likely demonstrating increased clinical suspicion for invasive bacterial infection in this group despite lacking national guidelines. Given continued vaccine hesitancy, further studies are needed for guiding management of febrile UnI and UnderI children presenting for emergency care.


Assuntos
Infecções Bacterianas , Febre , Humanos , Criança , Lactente , Estudos Retrospectivos , Febre/diagnóstico , Febre/tratamento farmacológico , Infecções Bacterianas/tratamento farmacológico , Serviço Hospitalar de Emergência , Antibacterianos/uso terapêutico
3.
Nature ; 488(7413): 603-8, 2012 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-22932384

RESUMO

Light-matter interactions are ubiquitous, and underpin a wide range of basic research fields and applied technologies. Although optical interactions have been intensively studied, their microscopic details are often poorly understood and have so far not been directly measurable. X-ray and optical wave mixing was proposed nearly half a century ago as an atomic-scale probe of optical interactions but has not yet been observed owing to a lack of sufficiently intense X-ray sources. Here we use an X-ray laser to demonstrate X-ray and optical sum-frequency generation. The underlying nonlinearity is a reciprocal-space probe of the optically induced charges and associated microscopic fields that arise in an illuminated material. To within the experimental errors, the measured efficiency is consistent with first-principles calculations of microscopic optical polarization in diamond. The ability to probe optical interactions on the atomic scale offers new opportunities in both basic and applied areas of science.

4.
Phys Rev Lett ; 119(10): 107204, 2017 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-28949160

RESUMO

Ultrafast x-ray scattering studies of the topological Skyrmion phase in Cu_{2}OSeO_{3} show the dynamics to be strongly dependent on the excitation energy and fluence. At high photon energies, where the electron-spin scattering cross section is relatively high, the excitation of the topological Skyrmion phase shows a nonlinear dependence on the excitation fluence, in contrast to the excitation of the conical phase which is linearly dependent on the excitation fluence. The excitation of the Skyrmion order parameter is nonlinear in the magnetic excitation resulting from scattering during electron-hole recombination, indicating different dominant scattering processes in the conical and Skyrmion phases.

5.
Phys Rev Lett ; 116(25): 254801, 2016 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-27391728

RESUMO

In this Letter we report the experimental demonstration of a new temporal shaping technique for x-ray free-electron lasers (FELs). This technique is based on the use of a spectrally shaped infrared (IR) laser and allows optical control of the x-ray generation process. By accurately manipulating the spectral amplitude and phase of the IR laser, we can selectively modify the electron bunch longitudinal emittance thus controlling the duration of the resulting x-ray pulse down to the femtosecond time scale. Unlike other methods currently in use, optical shaping is directly applicable to the next generation of high-average power x-ray FELs such as the Linac Coherent Light Source-II or the European X-FEL, and it enables pulse shaping of FELs at the highest repetition rates. Furthermore, this laser-shaping technique paves the way for flexible tailoring of complex multicolor FEL pulse patterns required for nonlinear multidimensional x-ray spectroscopy as well as novel multicolor diffraction imaging schemes.

6.
Hum Mol Genet ; 21(4): 900-15, 2012 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-22080836

RESUMO

Fragile X syndrome (FXS), caused by loss of the Fragile X Mental Retardation 1 (FMR1) gene product (FMRP), is the most common heritable cause of intellectual disability and autism spectrum disorders. It has been long hypothesized that the phosphorylation of serine 500 (S500) in human FMRP controls its function as an RNA-binding translational repressor. To test this hypothesis in vivo, we employed neuronally targeted expression of three human FMR1 transgenes, including wild-type (hFMR1), dephosphomimetic (S500A-hFMR1) and phosphomimetic (S500D-hFMR1), in the Drosophila FXS disease model to investigate phosphorylation requirements. At the molecular level, dfmr1 null mutants exhibit elevated brain protein levels due to loss of translational repressor activity. This defect is rescued for an individual target protein and across the population of brain proteins by the phosphomimetic, whereas the dephosphomimetic phenocopies the null condition. At the cellular level, dfmr1 null synapse architecture exhibits increased area, branching and bouton number. The phosphomimetic fully rescues these synaptogenesis defects, whereas the dephosphomimetic provides no rescue. The presence of Futsch-positive (microtubule-associated protein 1B) supernumerary microtubule loops is elevated in dfmr1 null synapses. The human phosphomimetic restores normal Futsch loops, whereas the dephosphomimetic provides no activity. At the behavioral level, dfmr1 null mutants exhibit strongly impaired olfactory associative learning. The human phosphomimetic targeted only to the brain-learning center restores normal learning ability, whereas the dephosphomimetic provides absolutely no rescue. We conclude that human FMRP S500 phosphorylation is necessary for its in vivo function as a neuronal translational repressor and regulator of synaptic architecture, and for the manifestation of FMRP-dependent learning behavior.


Assuntos
Proteína do X Frágil da Deficiência Intelectual/metabolismo , Neurônios/metabolismo , Animais , Animais Geneticamente Modificados , Encéfalo/citologia , Encéfalo/metabolismo , Encéfalo/patologia , Citoesqueleto/metabolismo , Citoesqueleto/patologia , Modelos Animais de Doenças , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/crescimento & desenvolvimento , Drosophila melanogaster/metabolismo , Proteína do X Frágil da Deficiência Intelectual/genética , Síndrome do Cromossomo X Frágil/genética , Síndrome do Cromossomo X Frágil/metabolismo , Humanos , Aprendizagem/fisiologia , Proteínas Associadas aos Microtúbulos/metabolismo , Mutação , Junção Neuromuscular/metabolismo , Junção Neuromuscular/patologia , Neurônios/patologia , Fosforilação , Fosfosserina/metabolismo , Biossíntese de Proteínas , Serina/genética , Serina/metabolismo , Transgenes
7.
Nat Mater ; 12(4): 293-8, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23503010

RESUMO

Ultrafast laser techniques have revealed extraordinary spin dynamics in magnetic materials that equilibrium descriptions of magnetism cannot explain. Particularly important for future applications is understanding non-equilibrium spin dynamics following laser excitation on the nanoscale, yet the limited spatial resolution of optical laser techniques has impeded such nanoscale studies. Here we present ultrafast diffraction experiments with an X-ray laser that probes the nanoscale spin dynamics following optical laser excitation in the ferrimagnetic alloy GdFeCo, which exhibits macroscopic all-optical switching. Our study reveals that GdFeCo displays nanoscale chemical and magnetic inhomogeneities that affect the spin dynamics. In particular, we observe Gd spin reversal in Gd-rich nanoregions within the first picosecond driven by the non-local transfer of angular momentum from larger adjacent Fe-rich nanoregions. These results suggest that a magnetic material's microstructure can be engineered to control transient laser-excited spins, potentially allowing faster (~ 1 ps) spin reversal than in present technologies.

8.
Phys Rev Lett ; 110(13): 134801, 2013 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-23581326

RESUMO

With an eye toward extending optical wave-mixing techniques to the x-ray regime, we present the first experimental demonstration of a two-color x-ray free-electron laser at the Linac Coherent Light Source. We combine the emittance-spoiler technique with a magnetic chicane in the undulator section to control the pulse duration and relative delay between two intense x-ray pulses and we use differently tuned canted pole undulators such that the two pulses have different wavelengths as well. Two schemes are shown to produce two-color soft x-ray pulses with a wavelength separation up to ∼1.9% and a controllable relative delay up to 40 fs.

9.
Phys Rev Lett ; 111(13): 134801, 2013 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-24116783

RESUMO

We show that the spectral properties of a self-amplified spontaneous emission x-ray free-electron laser can be controlled by modulating the gain in magnetic undulators, thus producing one or several spectral lines within a single few femtosecond pulse. By varying the magnetic field along the undulator and the electron beam transport line, the system we demonstrate can tailor the x-ray spectrum to optimally meet numerous experimental requirements for multicolor operation.

10.
Phys Rev Lett ; 110(18): 186101, 2013 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-23683223

RESUMO

We have studied the femtosecond dynamics following optical laser excitation of CO adsorbed on a Ru surface by monitoring changes in the occupied and unoccupied electronic structure using ultrafast soft x-ray absorption and emission. We recently reported [M. Dell'Angela et al. Science 339, 1302 (2013)] a phonon-mediated transition into a weakly adsorbed precursor state occurring on a time scale of >2 ps prior to desorption. Here we focus on processes within the first picosecond after laser excitation and show that the metal-adsorbate coordination is initially increased due to hot-electron-driven vibrational excitations. This process is faster than, but occurs in parallel with, the transition into the precursor state. With resonant x-ray emission spectroscopy, we probe each of these states selectively and determine the respective transient populations depending on optical laser fluence. Ab initio molecular dynamics simulations of CO adsorbed on Ru(0001) were performed at 1500 and 3000 K providing insight into the desorption process.


Assuntos
Monóxido de Carbono/química , Rutênio/química , Adsorção , Lasers , Simulação de Dinâmica Molecular , Fônons , Propriedades de Superfície , Espectroscopia por Absorção de Raios X/métodos
11.
Phys Rev Lett ; 111(7): 073002, 2013 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-23992061

RESUMO

When exposed to ultraintense x-radiation sources such as free electron lasers (FELs) the innermost electronic shell can efficiently be emptied, creating a transient hollow atom or molecule. Understanding the femtosecond dynamics of such systems is fundamental to achieving atomic resolution in flash diffraction imaging of noncrystallized complex biological samples. We demonstrate the capacity of a correlation method called "partial covariance mapping" to probe the electron dynamics of neon atoms exposed to intense 8 fs pulses of 1062 eV photons. A complete picture of ionization processes competing in hollow atom formation and decay is visualized with unprecedented ease and the map reveals hitherto unobserved nonlinear sequences of photoionization and Auger events. The technique is particularly well suited to the high counting rate inherent in FEL experiments.

12.
J Phys Chem Lett ; 14(1): 24-31, 2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36562987

RESUMO

An open-loop control scheme of molecular fragmentation based on transient molecular alignment combined with single-photon ionization induced by a short-wavelength free electron laser (FEL) is demonstrated for the acetylene cation. Photoelectron spectra are recorded, complementing the ion yield measurements, to demonstrate that such control is the consequence of changes in the electronic response with molecular orientation relative to the ionizing field. We show that stable C2H2+ cations are mainly produced when the molecules are parallel or nearly parallel to the FEL polarization, while the hydrogen fragmentation channel (C2H2+ → C2H+ + H) predominates when the molecule is perpendicular to that direction, thus allowing one to distinguish between the two photochemical processes. The experimental findings are supported by state-of-the art theoretical calculations.

13.
Opt Express ; 20(10): 11396-406, 2012 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-22565760

RESUMO

The recent development of x-ray free electron lasers providing coherent, femtosecond-long pulses of high brilliance and variable energy opens new areas of scientific research in a variety of disciplines such as physics, chemistry, and biology. Pump-probe experimental techniques which observe the temporal evolution of systems after optical or x-ray pulse excitation are one of the main experimental schemes currently in use for ultrafast studies. The key challenge in these experiments is to reliably achieve temporal and spatial overlap of the x-ray and optical pulses. Here we present measurements of the x-ray pulse induced transient change of optical reflectivity from a variety of materials covering the soft x-ray photon energy range from 500eV to 2000eV and outline the use of this technique to establish and characterize temporal synchronization of the optical-laser and FEL x-ray pulses.


Assuntos
Óptica e Fotônica/métodos , Eletroquímica/métodos , Eletrônica , Elétrons , Desenho de Equipamento , Lasers , Fótons , Semicondutores , Fatores de Tempo , Raios X
14.
Phys Rev Lett ; 109(1): 013602, 2012 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-23031104

RESUMO

We experimentally and theoretically study the coincidence count rate for down-converted x-ray photons. Because of photoionization, parametric down-conversion at x-ray wavelengths generally involves loss and the theoretical description requires a Langevin approach. By working in a transmission geometry (Laue) rather than in the Bragg geometry of previous experiments, we obtain an improvement in the signal-to-noise ratio of 12.5, and find agreement between experiment and theory.

15.
Phys Rev Lett ; 109(26): 263001, 2012 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-23368555

RESUMO

We investigate molecular dynamics of multiple ionization in N2 through multiple core-level photoabsorption and subsequent Auger decay processes induced by intense, short x-ray free electron laser pulses. The timing dynamics of the photoabsorption and dissociation processes is mapped onto the kinetic energy of the fragments. Measurements of the latter allow us to map out the average internuclear separation for every molecular photoionization sequence step and obtain the average time interval between the photoabsorption events. Using multiphoton ionization as a tool of the multiple-pulse pump-probe scheme, we demonstrate the modification of the ionization dynamics as we vary the x-ray laser pulse duration.

16.
Phys Rev Lett ; 108(6): 063007, 2012 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-22401068

RESUMO

Two-color (x-ray+infrared) electron spectroscopy is used for investigating laser-assisted KLL Auger decay following 1s photoionization of atomic Ne with few-femtosecond x-ray pulses from the Linac Coherent Light Source. In an angle-resolved experiment, the overall width of the laser-modified Auger-electron spectrum and its structure change significantly as a function of the emission angle. The spectra are characterized by a strong intensity variation of the sidebands revealing a gross structure. This variation is caused, as predicted by theory, by the interference of electrons emitted at different times within the duration of one optical cycle of the infrared dressing laser, which almost coincides with the lifetime of the Ne 1s vacancy.

17.
Health Psychol Res ; 10(3): 37445, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35999970

RESUMO

The COVID-19 pandemic introduced lockdown and social distancing measures that made new methods of healthcare essential. Telehealth was introduced as a temporary measure but is being considered as a more permanent form of healthcare, particularly in rural areas, to provide more equitable healthcare. A survey was conducted on 200 rural dwellers (residents) regarding their experience with rural healthcare, any barriers to adequate healthcare, and openness to telehealth. The results demonstrated interest in telehealth and predominately positive experiences with telehealth in the areas where there was need and lack of access to healthcare, more commonly expressed in the younger age group. Quality healthcare should be equitable and available for every individual irrespective of zip code or the county they live. Telehealth is capable of bridging the gap of lack of access and transportation for individuals in rural areas to meet their healthcare needs in a timely fashion in the coming years.

18.
Cureus ; 14(8): e28011, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36134073

RESUMO

BACKGROUND: The objectives of this study were: 1) estimate the impact and severity of both diagnosed and undiagnosed depression in the general US population 2) explore the demographics of depression based on its common symptoms 3) interpret Patient Health Questionnaire-9 (PHQ-9) scores to improve accuracy in identifying individuals with depression. METHODS:  A random sample of 200 individuals was selected from a general US adult population to complete the Patient Health Questionnaire-9 (PHQ-9). RESULTS: Only 39.4% of respondents indicated that they had a formal diagnosis of depression. In contrast, 53% of participants have considered seeking help from a mental health professional. More importantly, 31.45% of respondents without a formal diagnosis had a PHQ-9 score of over 10 (moderate to severe depression). CONCLUSIONS: The results indicate that undiagnosed depression exists in the US population and suggest that access to mental health services needs to expand across the nation.

19.
Cureus ; 14(8): e28109, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36158353

RESUMO

Background Recent studies have shown a higher incidence of complications from acute appendicitis in Hispanic populations. Hispanic ethnicity alone has been shown to be a risk factor. In contrast, one study found little evidence of racial disparities in complication rates. The objective of this study was to identify physician bias regarding whether ethnicity drives further testing after initial radiologic imaging has been obtained in the evaluation of appendicitis in our pediatric emergency department (PED). The use of computed tomography (CT) scan in the diagnosis of appendicitis was compared between Hispanic versus non-Hispanic populations when ultrasound (US) was indeterminate. Methodology This is a retrospective cohort study of Hispanic and non-Hispanic patients aged 2-18 who presented to the PED with right lower quadrant abdominal pain over a one-year period (January 1, 2017 to December 29, 2017). Both groups were subdivided into positive, negative, or indeterminate US findings for appendicitis. Each subgroup was analyzed based on those who had CT imaging done. Results A total of 471 ultrasounds were performed, 162 Hispanic and 309 non-Hispanic patients. Indeterminate US scans were documented in 90/162 (56%) Hispanic versus 155/309 (50%) non-Hispanic patients. Of those with indeterminate US scans, 30% Hispanic versus 32% non-Hispanic patients received CT scans. Negative US scans were documented in 54/162 (33%) Hispanic versus 102/309 (33%) non-Hispanic patients. Of those with negative US scans, 7% Hispanic versus 5% non-Hispanic patients received CT scans. Chi-square analysis comparing both the proportion of CT scans received for indeterminate US scans (p=0.71) and negative US scans (p=0.52) showed no statistical significance. Conclusions There was no significant difference in the number of CT scans ordered for indeterminate US scans between Hispanic and non-Hispanic patients. One can infer that there is no inherent bias toward ordering advanced imaging in Hispanic children based on ethnicity alone.

20.
Cureus ; 14(9): e29569, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36312605

RESUMO

INTRODUCTION: Vaso-occlusive crises (VOCs) are the leading cause of emergency department (ED) visits and hospitalizations in patients with sickle cell disease (SCD). Timely administration of analgesia, within 60 minutes of patient registration, is the standard of care for SCD patients with VOCs. Patients with VOCs have longer times to initial analgesia compared to similar painful conditions. The primary aim of the project is to have 75% of patients with VOCs receive initial analgesia within 60 minutes of being registered, the current recommended time frame from the National Heart, Lung, and Blood Institute (NHLBI). METHODS: A multi-disciplinary team used quality improvement (QI) methodology to develop a plan involving multiple Plan-Do-Study-Act (PDSA) cycles. A rapid evaluation process was employed which included notification of a patient with a VOC being placed in a room, rapid evaluation by all team members and use of an electronic order set. RESULTS: The aim was met 72% of the time during our intervention period, compared to 17% pre-intervention. Average time to initial analgesia was decreased from 61 minutes to 42 minutes (p-value < 0.001), while time to disposition was also decreased when time goals were achieved. CONCLUSION: Using a rapid evaluation process we were able to decrease time to initial analgesia in a patient population that has previously experienced delays in care and decrease overall time to disposition.

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