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1.
J Perinatol ; 42(9): 1266-1270, 2022 09.
Article in English | MEDLINE | ID: mdl-35732728

ABSTRACT

The knowledge and skills expected for board certification in Neonatal-Perinatal Medicine (NPM) should reflect the clinical practice of neonatology. First, a 14-member panel of practicing neonatologists, convened by the American Board of Pediatrics (ABP), drafted a practice analysis document which identified the practice domains, tasks, knowledge, and skills deemed essential for clinical practice. NPM fellowship program directors provided feedback via online survey resulting in revisions to the document. During the second phase of the project, the panel organized testable knowledge areas into content domains and subdomains to update the existing ABP NPM content outline. All ABP board-certified neonatologists were asked to review via online survey, and results were used to guide final revisions to the content outline. The NPM practice analysis document and the updated NPM content outline should serve as helpful resources for educators, trainees, and practicing neonatologists.


Subject(s)
Neonatology , Child , Fellowships and Scholarships , Humans , Infant, Newborn , Neonatologists , Surveys and Questionnaires , United States
2.
Int J Med Sci ; 18(13): 2905-2909, 2021.
Article in English | MEDLINE | ID: mdl-34220317

ABSTRACT

Objective: To investigate the association of a wide QRS-T angle on the surface ECG and late gadolinium enhancement on contrast-enhanced cardiovascular magnetic (CMR) imaging in patients with clinically suspected myocarditis. Background: Diagnosis and risk stratification in patients with suspected myocarditis is particularly challenging due to a great spectrum of clinical presentations. Late gadolinium enhancement (LGE) visualizes myocardial necrosis and fibrosis in patients with biopsy-proven myocarditis. The presence or absence of late gadolinium enhancements in these patients is prognostically meaningful. The QRS-T angle from the surface ECG, on the other hand, may serve as a simple and easily available risk marker in suspected myocarditis. Methods: We enrolled 97 consecutive patients that were referred to CMR imaging for a clinical suspicion of myocarditis. All patients obtained a standardized digital 12-lead ECG for the calculation of the QRS-T angle and underwent contrast-enhanced CMR imaging. Patients were divided into two groups according to the absence or presence of LGE on CMR. Results: 78 of 97 patients with suspected myocarditis had LGE on CMR. Patients with LGE had wider QRS-T angles as compared to the patient group without LGE (53.95-47.5 vs. 26.2-21.2; p<0.001). The sensivity, specificity, negative predictive value and positive predictive value for a QRS-T angle above 90 degrees for LGE positive myocarditis were 16.5%, 100%, 24.7%, and 100%, respectively. Conclusion: A wide QRS-T angle of 90 degrees or more is linked to myocardial fibrosis or necrosis (late gadolinium enhancement) in patients with suspected myocarditis.


Subject(s)
Heart/diagnostic imaging , Myocarditis/diagnosis , Myocardium/pathology , Adult , Aged , Biopsy , Contrast Media/administration & dosage , Electrocardiography , Female , Fibrosis , Gadolinium/administration & dosage , Humans , Magnetic Resonance Imaging/methods , Male , Middle Aged , Myocarditis/pathology , Necrosis/diagnosis , Necrosis/pathology , Predictive Value of Tests , Prognosis , Prospective Studies , Risk Assessment
3.
Int J Med Sci ; 17(15): 2264-2268, 2020.
Article in English | MEDLINE | ID: mdl-32922190

ABSTRACT

Background: The QRS-T angle from the surface EKG is a promising prognostic marker in patients with coronary artery disease. Cardiovascular magnetic resonance (CMR) imaging with late gadolinium enhancement (LGE) offers high resolution imaging of myocardial damage. We investigated the association of the QRS-T angle and the extent of myocardial damage as assessed by LGE in patients with acute ST-segment myocardial infarction (STEMI) Methods: 169 patients with STEMI obtained a standardized digital 12-lead EKG on admission for the calculation of the QRS-T angle and underwent CMR imaging for analysis of infarct size by LGE within the first week. Patients were divided into groups: (1) abnormal QRS-T angle ≥ 90 degree and (2) QRS-T angle < 90 degree. Results: Patients with a QRS-T angle of 90 degree or more had larger infarcts (36.5±12.4 vs. 13.3±9.5; p<0.001) and lower ejection fraction (42.9±12.1% vs. 50.6±10.6%; p<0.001). Conclusion: The extent of myocardial damage as measured by the gold standard LGE is associated with a larger QRS-T angle calculated from the surface EKG.


Subject(s)
Electrocardiography , Magnetic Resonance Imaging , ST Elevation Myocardial Infarction/diagnosis , Aged , Contrast Media/administration & dosage , Female , Gadolinium/administration & dosage , Heart/diagnostic imaging , Humans , Male , Middle Aged , Severity of Illness Index
4.
Phys Rev Lett ; 115(2): 026801, 2015 Jul 10.
Article in English | MEDLINE | ID: mdl-26207491

ABSTRACT

We report first experiments with a macroscopic-size superconducting microwave resonator that has the geometric structure of the C(60) fullerene molecule. Our high-resolution measurements reveal the exceptional spectral properties that stem from the icosahedral symmetry of its carbon lattice. In particular, they allow us to determine the number of zero-energy modes, i.e., of modes with energy values at the Dirac point existent in the band structure due to the hexagonal arrangements of the carbon atoms, and to test the Atiyah-Singer index theorem which relates this number to the topology of the curved carbon lattice.

5.
J Perinatol ; 35(3): 231-2, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25712598

ABSTRACT

A full-term female neonate presented with persistent respiratory failure and radiologic studies consistent with surfactant deficiency. Sequencing of the ATP-binding cassette transporter A3 gene (ABCA3) revealed three mutations: R280C, V1399M and Q1589X. The infant underwent bilateral lung transplantation at 9 months of age and is alive at 3 years of age. Parental sequencing demonstrated that two of the mutations (R280C and Q1589X) were oriented on the same allele (cis), whereas V1399M was oriented on the opposite allele (trans). As more than one mutation in ABCA3 can be present on the same allele, parental studies are needed to determine allelic orientation to inform clinical decision making and future reproductive counseling.


Subject(s)
ATP-Binding Cassette Transporters/genetics , Respiratory Distress Syndrome, Newborn/genetics , Respiratory Insufficiency/genetics , Alleles , DNA Mutational Analysis , Female , Humans , Infant , Infant, Newborn , Lung Transplantation , Mutation , Term Birth
6.
Chimia (Aarau) ; 66(9): 706-11, 2012.
Article in English | MEDLINE | ID: mdl-23211730

ABSTRACT

Carbon-supported ruthenium catalysts promote the gasification of aqueous organic feed with high efficiency to synthetic natural gas in supercritical water. Ruthenium metal was recently identified as the catalytically active species. [1] Occasionally deactivation is observed. To understand the deactivation, the fresh and several spent catalyst samples were investigated by RBS, ERDA, and XPS. The data revealed a massive reduction of the ruthenium concentration in toto and especially of the surface concentration. Of importance is the almost complete disappearance of the spectral features in the valance band region. Coverage of the ruthenium clusters e.g. with a thin 'carbonaceous' layer, i.e. a kind of fouling, or structural modifications of the ruthenium clusters might be the origin. Additionally, leaching of ruthenium might contribute, but is not considered a major effect, because ruthenium was never found in the liquid effluent of the reactor. The influence of additionally detected corrosion products (Ni, Cr, Fe, Ti) from the stainless steel and the titanium alloy walls seems to be small. No evidence for a deactivation by sulphur could be found.


Subject(s)
Biomass , Carbon/chemistry , Gases/chemistry , Ruthenium/chemistry , Water/chemistry , Catalysis
7.
Rev Sci Instrum ; 83(5): 054101, 2012 May.
Article in English | MEDLINE | ID: mdl-22667633

ABSTRACT

This paper presents the design and performance of a novel high-temperature and high-pressure continuous-flow reactor, which allows for x-ray absorption spectroscopy or diffraction in supercritical water and other fluids under high pressure and temperature. The in situ cell consists of a tube of sintered, polycrystalline aluminum nitride, which is tolerant to corrosive chemical media, and was designed to be stable at temperatures up to 500 °C and pressures up to 30 MPa. The performance of the reactor is demonstrated by the measurement of extended x-ray absorption fine structure spectra of a carbon-supported ruthenium catalyst during the continuous hydrothermal gasification of ethanol in supercritical water at 400 °C and 24 MPa.


Subject(s)
X-Ray Absorption Spectroscopy/instrumentation , Carbon/chemistry , Catalysis , Equipment Design , Ethanol/chemistry , Phase Transition , Pressure , Ruthenium/chemistry , Safety , Temperature
8.
J Synchrotron Radiat ; 19(Pt 1): 1-9, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22186638

ABSTRACT

Today, the vast majority of electron storage rings delivering synchrotron radiation for general user operation offer a dedicated infrared port. There is growing interest expressed by various scientific communities to exploit the mid-IR emission in microspectroscopy, as well as the far infrared (also called THz) range for spectroscopy. Compared with a thermal (laboratory-based source), IR synchrotron radiation sources offer enhanced brilliance of about two to three orders of magnitude in the mid-IR energy range, and enhanced flux and brilliance in the far-IR energy range. Synchrotron radiation also has a unique combination of a broad wavelength band together with a well defined time structure. Thermal sources (globar, mercury filament) have excellent stability. Because the sampling rate of a typical IR Fourier-transform spectroscopy experiment is in the kHz range (depending on the bandwidth of the detector), instabilities of various origins present in synchrotron radiation sources play a crucial role. Noise recordings at two different IR ports located at the Swiss Light Source and SOLEIL (France), under conditions relevant to real experiments, are discussed. The lowest electron beam fluctuations detectable in IR spectra have been quantified and are shown to be much smaller than what is routinely recorded by beam-position monitors.

9.
Phys Rev Lett ; 107(6): 062502, 2011 Aug 05.
Article in English | MEDLINE | ID: mdl-21902316

ABSTRACT

A benchmark experiment on (208)Pb shows that polarized proton inelastic scattering at very forward angles including 0° is a powerful tool for high-resolution studies of electric dipole (E1) and spin magnetic dipole (M1) modes in nuclei over a broad excitation energy range to test up-to-date nuclear models. The extracted E1 polarizability leads to a neutron skin thickness r(skin) = 0.156(-0.021)(+0.025) fm in (208)Pb derived within a mean-field model [Phys. Rev. C 81, 051303 (2010)], thereby constraining the symmetry energy and its density dependence relevant to the description of neutron stars.

10.
Phys Rev Lett ; 106(6): 062501, 2011 Feb 11.
Article in English | MEDLINE | ID: mdl-21405463

ABSTRACT

The coupling of the giant quadrupole resonance to valence-space configurations is shown to be the origin of the formation of low-lying quadrupole-collective structures in vibrational nuclei with symmetric and mixed-symmetric character with respect to the proton-neutron degree of freedom. For the first time experimental evidence for this picture is obtained from electron- and proton scattering experiments on the nucleus ^{92}Zr that are sensitive to the relative phase of valence-space amplitudes by quantum interference.

11.
Phys Rev Lett ; 99(9): 092503, 2007 Aug 31.
Article in English | MEDLINE | ID: mdl-17931002

ABSTRACT

High-energy-resolution inelastic electron scattering (at the S-DALINAC) and proton scattering (at iThemba LABS) experiments permit a thorough test of the nature of proposed one- and two-phonon symmetric and mixed-symmetric 2+ states of the nucleus 94Mo. The combined analysis reveals the one-phonon content of the mixed-symmetry state and its isovector character suggested by microscopic nuclear model calculations. The purity of two-phonon 2+ states is extracted.

12.
Phys Rev E Stat Nonlin Soft Matter Phys ; 73(1 Pt 2): 016204, 2006 Jan.
Article in English | MEDLINE | ID: mdl-16486255

ABSTRACT

We consider the relation between relaxation time and the largest Lyapunov exponent in a system of two coupled oscillators, one of them being harmonic. It has been found that in a rather broad region of parameter space, contrary to the common expectation, both Lyapunov exponent and relaxation time increase as a function of the total energy. This effect is attributed to the fact that above a critical value of the total energy, although the Lyapunov exponent increases, Kolmogorov-Arnold-Moser tori appear and the chaotic fraction of phase space decreases. We examine the required conditions and demonstrate the key role of the dispersion relation for this behavior to occur. This study is useful, among other things, in the understanding of the damping of nuclear giant resonances.

13.
Phys Rev Lett ; 96(1): 012502, 2006 Jan 13.
Article in English | MEDLINE | ID: mdl-16486449

ABSTRACT

The fine structure of the Gamow-Teller resonance in a medium-heavy nucleus is observed for the first time in a high-resolution 90Zr(3He,t)90Nb experiment at the Research Center for Nuclear Physics, Osaka. Using a novel wavelet analysis technique, it is possible to extract characteristic energy scales and to quantify their relative importance for the generation of the fine structure. This method combined with the selectivity of the reaction permits an extraction of the level density of 1+ states in 90Nb.

14.
Phys Rev Lett ; 93(12): 122501, 2004 Sep 17.
Article in English | MEDLINE | ID: mdl-15447256

ABSTRACT

Fine structure in the energy region of the isoscalar giant quadrupole resonance in nuclei is observed in high-resolution proton scattering experiments at iThemba LABS over a wide mass range. A novel method based on wavelet transforms is introduced for the extraction of scales characterizing the fine structure. A comparison with microscopic model calculations including two-particle two-hole (2p2h) degrees of freedom identifies the coupling to surface vibrations as the main source of the observed scales. A generic pattern is also found for the stochastic coupling to the background of the more complex states.

15.
Phys Rev Lett ; 89(27): 272502, 2002 Dec 30.
Article in English | MEDLINE | ID: mdl-12513199

ABSTRACT

A high-resolution (gamma,gamma') study of the electric dipole response in 208Pb at the S-DALINAC reveals a resonance structure centered around the neutron emission threshold. Microscopic quasiparticle phonon model calculations in realistic model spaces including the coupling to complex configurations are able to describe the data in great detail. The resonance is shown to result from surface density oscillations of the neutron skin relative to an approximately isospin-saturated core. It also forms an integral part of a toroidal E1 mode representing an example of vortex collective motion in nuclei.

17.
Phys Rev Lett ; 85(14): 2913-6, 2000 Oct 02.
Article in English | MEDLINE | ID: mdl-11005966

ABSTRACT

The 48Ca(e,e(')n) reaction has been investigated for excitation energies 11-25 MeV and momentum transfers 0.22-0.43 fm(-1) at the superconducting Darmstadt electron linear accelerator S-DALINAC. Electric dipole and quadrupole plus monopole strength distributions are extracted from a multipole decomposition of the spectra. Their fragmented structure is described by microscopic calculations allowing for coupling of the basic particle-hole excitations to more complex configurations. Comparison of the excitation spectrum of the residual nucleus 47Ca with statistical model calculations reveals a 39(5)% contribution of direct decay to the damping of the giant dipole resonance.

19.
Phys Rev C Nucl Phys ; 53(6): 3057-3068, 1996 Jun.
Article in English | MEDLINE | ID: mdl-9971294
20.
Phys Rev Lett ; 76(26): 4891-4894, 1996 Jun 24.
Article in English | MEDLINE | ID: mdl-10061406
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