1044 Simple echocardiographic scoring in screening for aortic stenosis by emergency physicians in the emergency department

Background; Aortic stenosis (AS) is one of the important critical diseases and may influence hemodynamics in cardiovascular or non-cardiovascular emergency, however, there is no established methodology to diagnose AS in a focused cardiac ultrasound (FOCUS). We have previously reported that our developed visual AS score was a simple index for AS screening using rapid echocardiography and it could successfully diagnose clinically significant AS. The purpose of the present study was to evaluate the diagnostic accuracy of visual AS score assessed by emergency physicians in the emergency department. Methods; Visual AS score was calculated as the sum of the scores of each three aortic cusp’s opening in a short-axis view scored as follows: 0 = not restricted, 1 = restricted, or 2 = severely restricted; and classified in 0 – 6 as we previously reported. Emergency physicians who did not specialize in cardiology or ultrasonography underwent basic 30 minutes training to visualize aortic valve in a short-axis view and to assess visual AS score beforehand. They performed echocardiography and evaluated visual AS score in emergency outpatients with suspected cardiovascular diseases such as chest symptom, consciousness disorder, abnormal vital signs, heart murmur or abnormal electrocardiogram in the emergency department. Then, another assessment of visual AS score and complete echocardiography including quantitative assessment of AS was performed by expert sonographers. Aortic valve area index (AVAI) was calculated using continuity equation and body surface area, and an AVAI > 0.85 cm/m2, 0.6 - 0.85 cm/m2, and < 0.6 cm/m2 were defined as none or mild, moderate and severe AS, respectively. Results: Sixty patients underwent evaluations of visual AS score by emergency physicians. Visual AS score could not be assessed in 5 patients and continuity equation could not be evaluated in 2 patients, both due to poor echocardiographic imaging quality. Visual AS scores assessed by emergency physicians and expert sonographers showed strong positive correlation (R = 0.94, P < 0.0001). Fourteen patients (26 %) including 6 with shock or hypotension, 3 with congestive heart failure, 2 with syncope, 1 with acute myocardial infarction, 1 with suspected cardiac tamponade and 1 with abnormal electrocardiogram had moderate or more degree of AS in complete echocardiography performed by expert sonographers. Visual AS score 3 or more assessed by emergency physicians had 86 %, 100 %, 100 % and 95 % of a diagnostic sensitivity, specificity, positive predictive value and negative predictive value, respectively. Conclusion: Visual AS score in FOCUS is useful to screen for AS for emergency physicians who do not specialize in cardiology.

Cross-section measurement in the reactions of 136Xe on proton, deuteron and carbon

The isotopic production cross sections for the reactions of 136Xe induced by proton, deuteron and carbon at 168 MeV/u were obtained by using the inverse kinematics technique at RIKEN Radioactive Isotope Beam Factory. The target dependence of the cross sections was investigated systematically. It was found that for the light-mass products, the cross sections on carbon are larger than those on deuteron and proton. The measured cross sections on proton were compared with the previous data at higher reaction energies to study the energy dependence. The experimental results were compared with the theoretical calculations including both the intranuclear cascade and evaporation processes using PHITS and with the EPAX and SPACS empirical parameterizations.

Quasifree Neutron Knockout from ^{54}Ca Corroborates Arising N=34 Neutron Magic Number

Exclusive cross sections and momentum distributions have been measured for quasifree one-neutron knockout reactions from a ^{54}Ca beam striking on a liquid hydrogen target at ∼200  MeV/u. A significantly larger cross section to the p_{3/2} state compared to the f_{5/2} state observed in the excitation of ^{53}Ca provides direct evidence for the nature of the N=34 shell closure. This finding corroborates the arising of a new shell closure in neutron-rich calcium isotopes. The distorted-wave impulse approximation reaction formalism with shell model calculations using the effective GXPF1Bs interaction and ab initio calculations concur our experimental findings. Obtained transverse and parallel momentum distributions demonstrate the sensitivity of quasifree one-neutron knockout in inverse kinematics on a thick liquid hydrogen target with the reaction vertex reconstructed to final state spin-parity assignments.

P1825The characteristics of type A acute aortic dissection in patients with out-of-hospital cardiopulmonary arrest analyzed by computed tomography

Background/Introduction

Acute aortic dissection (AAD) is a life-threatening condition associated with high morbidity and mortality rates, and is reported to have a 1–2% fatality rate per hour after onset. Therefore, many cases with AAD are considered to be included in patients with out-of-hospital cardiopulmonary arrest (OHCPA). However at this time, there is a lack of documentation of these cases.

Purpose

In this study, we investigated the characteristics of Stanford type A AAD (TAAD) cases between OHCPA cases and survival cases using acute phase CT.

Methods

An acute phase CT scanning was performed on consecutive patients with OHCPA transported to our hospital in order to estimate the causes of cardiopulmonary arrest (CPA). Based on our emergency outpatient databases, we retrospectively reviewed the acute phase CT findings of OHCPA TAAD cases and survival TAAD cases diagnosed at our hospital during the same period.

Results

Of 1,011 consecutive patients with OHCPA, except for exogenous death from 1 January 2015 to 31 December 2017, 934 patients underwent CT examination in the acute phase. Based on the clinical course and CT findings, 71 of the 934 patients (7.6%) were diagnosed with AAD. Out of 71 AAD patients, 66 were TAAD patients, and all of these patients were enrolled in the OHCPA group. On the other hand, 41 patients were registered as the survival group during the same period. These patients were diagnosed as TAAD and were admitted to our hospital without falling into CPA. Increased Age (78±8 years old vs 69±13 years old, P<0.01), visible intimal flap (63.6% vs 41.5%, P=0.043), bloody pericardial effusion (72.7% vs 26.8%, P<0.01), hemothorax (24.2% vs 0%, P<0.01) were significant in patients with the OHCPA group compared with the survival group. In addition, 56 patients with OHCPA (84.8%) had at least one of massive bloody pericardial effusion or massive hemothorax. Using multivariate logistic regression analysis, increased age and bloody pericardial effusion were both found to be independent factors related to OHCPA.

Conclusion

In this study, it is thought that the main characteristics of the CT findings with OHCPA due to TAAD are a rupture of the aorta into the pericardial cavity or thoracic cavity.

Prominence of Pairing in Inclusive (p,2p) and (p,pn) Cross Sections from Neutron-Rich Nuclei

Fifty-five inclusive single nucleon-removal cross sections from medium mass neutron-rich nuclei impinging on a hydrogen target at ∼250  MeV/nucleon are measured at the RIKEN Radioactive Isotope Beam Factory. Systematically higher cross sections are found for proton removal from nuclei with an even number of protons as compared to odd-proton number projectiles for a given neutron separation energy. Neutron removal cross sections display no even-odd splitting, contrary to nuclear cascade model predictions. Both effects are understood through simple considerations of neutron separation energies and bound state level densities originating in pairing correlations in the daughter nuclei. These conclusions are supported by comparison with semimicroscopic model predictions, highlighting the enhanced role of low-lying level densities in nucleon-removal cross sections from loosely bound nuclei.

How Robust is the N=34 Subshell Closure? First Spectroscopy of ^{52}Ar

The first γ-ray spectroscopy of ^{52}Ar, with the neutron number N=34, was measured using the ^{53}K(p,2p) one-proton removal reaction at ∼210  MeV/u at the RIBF facility. The 2_{1}^{+} excitation energy is found at 1656(18) keV, the highest among the Ar isotopes with N>20. This result is the first experimental signature of the persistence of the N=34 subshell closure beyond ^{54}Ca, i.e., below the magic proton number Z=20. Shell-model calculations with phenomenological and chiral-effective-field-theory interactions both reproduce the measured 2_{1}^{+} systematics of neutron-rich Ar isotopes, and support a N=34 subshell closure in ^{52}Ar.

First Spectroscopy of the Near Drip-line Nucleus ^{40}Mg

One of the most exotic light neutron-rich nuclei currently accessible for experimental study is ^{40}Mg, which lies at the intersection of the nucleon magic number N=28 and the neutron drip line. Low-lying excited states of ^{40}Mg have been studied for the first time following a one-proton removal reaction from ^{41}Al, performed at the Radioactive Isotope Beam Factory of RIKEN Nishina Center with the DALI2 γ-ray array and the ZeroDegree spectrometer. Two γ-ray transitions were observed, suggesting an excitation spectrum that shows unexpected properties as compared to both the systematics along the Z=12, N≥20  Mg isotopes and available state-of-the-art theoretical model predictions. A possible explanation for the observed structure involves weak-binding effects in the low-lying excitation spectrum.

First Observation of ^{20}B and ^{21}B

The most neutron-rich boron isotopes ^{20}B and ^{21}B have been observed for the first time following proton removal from ^{22}N and ^{22}C at energies around 230  MeV/nucleon. Both nuclei were found to exist as resonances which were detected through their decay into ^{19}B and one or two neutrons. Two-proton removal from ^{22}N populated a prominent resonancelike structure in ^{20}B at around 2.5 MeV above the one-neutron decay threshold, which is interpreted as arising from the closely spaced 1^{-},2^{-} ground-state doublet predicted by the shell model. In the case of proton removal from ^{22}C, the ^{19}B plus one- and two-neutron channels were consistent with the population of a resonance in ^{21}B 2.47±0.19  MeV above the two-neutron decay threshold, which is found to exhibit direct two-neutron decay. The ground-state mass excesses determined for ^{20,21}B are found to be in agreement with mass surface extrapolations derived within the latest atomic-mass evaluations.

A definition of bioinks and their distinction from biomaterial inks

Biofabrication aims to fabricate biologically functional products through bioprinting or bioassembly (Groll et al 2016 Biofabrication 8 013001). In biofabrication processes, cells are positioned at defined coordinates in three-dimensional space using automated and computer controlled techniques (Moroni et al 2018 Trends Biotechnol. 36 384-402), usually with the aid of biomaterials that are either (i) directly processed with the cells as suspensions/dispersions, (ii) deposited simultaneously in a separate printing process, or (iii) used as a transient support material. Materials that are suited for biofabrication are often referred to as bioinks and have become an important area of research within the field. In view of this special issue on bioinks, we aim herein to briefly summarize the historic evolution of this term within the field of biofabrication. Furthermore, we propose a simple but general definition of bioinks, and clarify its distinction from biomaterial inks.

Erratum: Persistence of the Z=28 Shell Gap Around ^{78}Ni: First Spectroscopy of ^{79}Cu [Phys. Rev. Lett. 119, 192501 (2017)]

This corrects the article DOI: 10.1103/PhysRevLett.119.192501.

Magic Nature of Neutrons in ^{54}Ca: First Mass Measurements of ^{55-57}Ca

We perform the first direct mass measurements of neutron-rich calcium isotopes beyond neutron number 34 at the RIKEN Radioactive Isotope Beam Factory by using the time-of-flight magnetic-rigidity technique. The atomic mass excesses of ^{55-57}Ca are determined for the first time to be -18650(160), -13510(250), and -7370(990)  keV, respectively. We examine the emergence of neutron magicity at N=34 based on the new atomic masses. The new masses provide experimental evidence for the appearance of a sizable energy gap between the neutron 2p_{1/2} and 1f_{5/2} orbitals in ^{54}Ca, comparable to the gap between the neutron 2p_{3/2} and 2p_{1/2} orbitals in ^{52}Ca. For the ^{56}Ca nucleus, an open-shell property in neutrons is suggested.

Excitation of the Isovector Spin Monopole Resonance via the Exothermic ^{90}Zr(^{12}N,^{12}C) Reaction at 175 MeV/u

The (^{12}N, ^{12}C) charge-exchange reaction at 175  MeV/u was developed as a novel probe for studying the isovector spin giant monopole resonance (IVSMR), whose properties are important for better understanding the bulk properties of nuclei and asymmetric nuclear matter. This probe, now available through the production of ^{12}N as a secondary rare-isotope beam, is exothermic, is strongly absorbed at the surface of the target nucleus, and provides selectivity for spin-transfer excitations. All three properties enhance the excitation of the IVSMR compared to other, primarily light-ion, probes, which have been used to study the IVSMR thus far. The ^{90}Zr(^{12}N,^{12}C) reaction was measured and the excitation energy spectra up to about 70 MeV for both the spin-transfer and non-spin-transfer channels were deduced separately by tagging the decay by γ emission from the ^{12}C ejectile. Besides the well-known Gamow-Teller and isobaric analog transitions, a clear signature of the IVSMR was identified. By comparing with the results from light-ion reactions on the same target nucleus and theoretical predictions, the suitability of this new probe for studying the IVSMR was confirmed.

Persistence of the Z=28 Shell Gap Around ^{78}Ni: First Spectroscopy of ^{79}Cu

In-beam γ-ray spectroscopy of ^{79}Cu is performed at the Radioactive Isotope Beam Factory of RIKEN. The nucleus of interest is produced through proton knockout from a ^{80}Zn beam at 270  MeV/nucleon. The level scheme up to 4.6 MeV is established for the first time and the results are compared to Monte Carlo shell-model calculations. We do not observe significant knockout feeding to the excited states below 2.2 MeV, which indicates that the Z=28 gap at N=50 remains large. The results show that the ^{79}Cu nucleus can be described in terms of a valence proton outside a ^{78}Ni core, implying the magic character of the latter.