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1.
Phys Rev Lett ; 126(15): 152701, 2021 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-33929230

RESUMEN

The discrepancy between observations from γ-ray astronomy of the ^{60}Fe/^{26}Al γ-ray flux ratio and recent calculations is an unresolved puzzle in nuclear astrophysics. The stellar ß-decay rate of ^{59}Fe is one of the major nuclear uncertainties impeding us from a precise prediction. The important Gamow-Teller strengths from the low-lying states in ^{59}Fe to the ^{59}Co ground state are measured for the first time using the exclusive measurement of the ^{59}Co(t,^{3}He+γ)^{59}Fe charge-exchange reaction. The new stellar decay rate of ^{59}Fe is a factor of 3.5±1.1 larger than the currently adopted rate at T=1.2 GK. Stellar evolution calculations show that the ^{60}Fe production yield of an 18 solar mass star is decreased significantly by 40% when using the new rate. Our result eliminates one of the major nuclear uncertainties in the predicted yield of ^{60}Fe and alleviates the existing discrepancy of the ^{60}Fe/^{26}Al ratio.

2.
Pharmazie ; 76(2): 114-118, 2021 02 25.
Artículo en Inglés | MEDLINE | ID: mdl-33714289

RESUMEN

Introduction: Considering the physique of the Japanese population, the standard daily vancomycin dose of 2 g/day and doses ≥ 3 g/day are high in terms of dose per body weight. Studies have reported that administering high-dose vancomycin to achieve a high target trough concentration has been associated with nephrotoxicity. The risk of high-dose vancomycin-associated nephrotoxicity is believed to be exceptionally high for Japanese patients because of their relatively low body weights, but data on the population is lacking. In this retrospective study, we aimed to evaluate risk factors associated with nephrotoxicity in Japanese patients treated with vancomycin. Methods: We examined the medical records of 107 Japanese patients who received vancomycin (3 to 4 g/day). They were divided into two groups based on the presence or absence of nephrotoxicity, and their demographics and clinical characteristics were compared. Results : The incidence of nephrotoxicity in patients receiving high-dose vancomycin was 13%. Age (≥ 60 years) and concurrent use of piperacillin/tazobactam were independent risk factors for vancomycin-associated nephrotoxicity (P = 0.027 and 0.017, respectively). Conclusions : We conclude that the nephrotoxicity risk of high-dose vancomycin in Japanese patients is not excessively high when administered within the confines of a therapeutic drug-monitoring program. However, special care must be taken with patients who are older or on concurrent piperacillin/tazobactam therapy.


Asunto(s)
Lesión Renal Aguda/inducido químicamente , Antibacterianos/administración & dosificación , Antibacterianos/efectos adversos , Vancomicina/administración & dosificación , Vancomicina/toxicidad , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Humanos , Japón , Riñón/efectos de los fármacos , Riñón/lesiones , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo
3.
Phys Rev Lett ; 124(15): 152501, 2020 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-32357059

RESUMEN

The lifetimes of the first excited 2^{+} states in the N=Z nuclei ^{80}Zr, ^{78}Y, and ^{76}Sr have been measured using the γ-ray line shape method following population via nucleon-knockout reactions from intermediate-energy rare-isotope beams. The extracted reduced electromagnetic transition strengths yield new information on where the collectivity is maximized and provide evidence for a significant, and as yet unexplained, odd-odd vs even-even staggering in the observed values. The experimental results are analyzed in the context of state-of-the-art nuclear density-functional model calculations.

5.
Water Sci Technol ; 81(3): 529-534, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32385206

RESUMEN

Sludge filterability in membrane bioreactors (MBRs) fluctuates and affects membrane fouling. Therefore, understanding the reasons for the fluctuations of sludge filterability is important for the efficient operation of MBRs. In this study, a pilot-scale MBR treating municipal wastewater was operated for about 600 days and the variations in sludge filterability were continuously monitored by batch-filtration experiments using the same membranes as in the MBR. To investigate the reasons for the deterioration of sludge filterability, constituents in sludge supernatant were intensively monitored, and the correlations with sludge filterability were determined. The concentration of lipopolysaccharides (LPS) in sludge supernatant exhibited significantly higher correlation with sludge filterability than did conventional indexes (i.e. polysaccharides and proteins). Size fractions affecting MBR sludge filterability were also investigated, and it was suggested that colloidal LPS deteriorated MBR sludge filterability. Based on the long-term operation of the MBR, increase in colloidal LPS under low temperatures of the mixed liquor suspension was a key factor in the deterioration of sludge filterability. The impact of LPS increasing under low temperatures should be investigated by operating bench-scale MBRs fed with synthetic wastewater in controlled conditions.


Asunto(s)
Lipopolisacáridos , Membranas Artificiales , Reactores Biológicos , Filtración , Aguas del Alcantarillado , Temperatura , Eliminación de Residuos Líquidos
6.
Malays J Pathol ; 42(2): 259-265, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32860379

RESUMEN

INTRODUCTION: Carcinoma showing thymus-like differentiation (CASTLE) is a rare tumour that mainly arises from the thyroid gland, or occasionally, from the head and neck. Although the 10-year survival rate of patients with CASTLE is approximately 80%, local recurrence and distant metastasis are observed in some cases. A recent systematic review for CASTLE indicated that the prognostic factors are treatment-dependent, and postoperative radiotherapy significantly improves patient survival. CASE REPORT: Herein, we describe and compare three cases of CASTLE, including a case with distant metastasis despite administering postoperative chemotherapy. Thus, the mechanisms underlying metastasis of CASTLE are unclear. This case study helps to elucidate the histopathological risk factors of metastasis in CASTLE. DISCUSSION: We found that prominent lymphovascular invasion and higher proliferative activities might be risk factors of metastasis in CASTLE. In addition, we have summarised the cytological, morphological, and immunohistochemical features of CASTLE for an accurate diagnosis.


Asunto(s)
Carcinoma/patología , Neoplasias de la Tiroides/patología , Anciano , Diferenciación Celular , Femenino , Humanos , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia/patología , Neoplasias del Timo , Glándula Tiroides/patología
7.
Phys Rev Lett ; 121(8): 082502, 2018 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-30192612

RESUMEN

Neutron-deficient selenium isotopes are thought to undergo a rapid shape change from a prolate deformation near the line of beta stability towards oblate deformation around the line of N=Z. The point at which this shape change occurs is unknown, with inconsistent predictions from available theoretical models. A common feature in the models is the delicate nature of the point of transition, with the introduction of even a modest spin to the system sufficient to change the ordering of the prolate and oblate configurations. We present a measurement of the quadrupole moment of the first-excited state in radioactive ^{72}Se-a potential point of transition-by safe Coulomb excitation. This is the first low-energy Coulomb excitation to be performed with a rare-isotope beam at the reaccelerated beam facility at the National Superconducting Cyclotron Laboratory. By demonstrating a negative spectroscopic quadrupole moment for the first-excited 2^{+} state, it is found that any low-spin shape change in neutron-deficient selenium does not occur until ^{70}Se.

8.
Phys Rev Lett ; 121(1): 012501, 2018 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-30028163

RESUMEN

Lifetime measurements of excited states in the neutron-rich nucleus ^{43}S were performed by applying the recoil-distance method on fast rare-isotope beams in conjunction with the Gamma-Ray Energy Tracking In-beam Nuclear Array. The new data based on γγ coincidences and lifetime measurements resolve a doublet of (3/2^{-}) and (5/2^{-}) states at low excitation energies. Results were compared to the π(sd)-ν(pf) shell model and antisymmetrized molecular dynamics calculations. The consistency with the theoretical calculations identifies a possible appearance of three coexisting bands near the ground state of ^{43}S: the K^{π}=1/2^{-} band built on a prolate-deformed ground state, a band built on an isomer with a 1f_{7/2}^{-1} character, and a suggested excited band built on a newly discovered doublet state. The latter further confirms the collapse of the N=28 shell closure in the neutron-rich region.

9.
Phys Rev Lett ; 121(26): 262501, 2018 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-30636164

RESUMEN

An enhanced low-energy electric dipole (E1) strength is identified for the weakly bound excited states of the neutron-rich isotope ^{27}Ne. The Doppler-shift lifetime measurements employing a combination of the γ-ray tracking array GRETINA, the plunger device, and the S800 spectrograph determine the lower limit of 0.030 e^{2} fm^{2} or 0.052 W.u. for the 1/2^{+}→3/2^{-} E1 transition in ^{27}Ne, representing one of the strongest E1 strengths observed among the bound discrete states in this mass region. This value is at least 30 times larger than that measured for the 3/2^{-} decay to the 3/2_{gs}^{+} ground state. A comparison of the present results to large-scale shell-model calculations points to an important role of core excitations and deformation in the observed E1 enhancement, suggesting a novel example of the electric dipole modes manifested in weakly bound deformed systems.

10.
Phys Rev Lett ; 118(5): 052501, 2017 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-28211717

RESUMEN

Previous experiments observed a 4^{+} state in the N=28 nucleus ^{44}S and suggested that this state may exhibit a hindered E2-decay rate, inconsistent with being a member of the collective ground state band. We populate this state via two-proton knockout from a beam of exotic ^{46}Ar projectiles and measure its lifetime using the recoil distance method with the GRETINA γ-ray spectrometer. The result, 76(14)_{stat}(20)_{syst} ps, implies a hindered transition of B(E2;4^{+}→2_{1}^{+})=0.61(19) single-particle or Weisskopf units strength and supports the interpretation of the 4^{+} state as a K=4 isomer, the first example of a high-K isomer in a nucleus of such low mass.

11.
Phys Rev Lett ; 116(12): 122502, 2016 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-27058074

RESUMEN

The lifetimes of the first excited 2^{+} and 4^{+} states in ^{72}Ni were measured at the National Superconducting Cyclotron Laboratory with the recoil-distance Doppler-shift method, a model-independent probe to obtain the reduced transition probability. Excited states in ^{72}Ni were populated by the one-proton knockout reaction of an intermediate energy ^{73}Cu beam. γ-ray-recoil coincidences were detected with the γ-ray tracking array GRETINA and the S800 spectrograph. Our results provide evidence of enhanced transition probability B(E2;2^{+}→0^{+}) as compared to ^{68}Ni, but do not confirm the trend of large B(E2) values reported in the neighboring isotope ^{70}Ni obtained from Coulomb excitation measurement. The results are compared to shell model calculations. The lifetime obtained for the excited 4_{1}^{+} state is consistent with models showing decay of a seniority ν=4, 4^{+} state, which is consistent with the disappearance of the 8^{+} isomer in ^{72}Ni.

12.
Phys Rev Lett ; 117(8): 082502, 2016 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-27588851

RESUMEN

One-neutron knockout reactions have been performed on a beam of radioactive ^{53}Co in a high-spin isomeric state. The analysis is shown to yield a highly selective population of high-spin states in an exotic nucleus with a significant cross section, and hence represents a technique that is applicable to the planned new generation of fragmentation-based radioactive beam facilities. Additionally, the relative cross sections among the excited states can be predicted to a high level of accuracy when reliable shell-model input is available. The work has resulted in a new level scheme, up to the 11^{+} band-termination state, of the proton-rich nucleus ^{52}Co (Z=27, N=25). This has in turn enabled a study of mirror energy differences in the A=52 odd-odd mirror nuclei, interpreted in terms of isospin-nonconserving (INC) forces in nuclei. The analysis demonstrates the importance of using a full set of J-dependent INC terms to explain the experimental observations.

13.
Phys Rev Lett ; 112(14): 142502, 2014 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-24765947

RESUMEN

The transition rates from the yrast 2+ and 4+ states in the self-conjugate 72Kr nucleus were studied via lifetime measurements employing the GRETINA array with a novel application of the recoil-distance method. The large collectivity observed for the 4+→2+ transition suggests a prolate character of the excited states. The reduced collectivity previously reported for the 2+→0+ transition was confirmed. The irregular behavior of collectivity points to the occurrence of a rapid oblate-prolate shape transition in 72Kr, providing stringent tests for advanced theories to describe the shape coexistence and its evolution.

14.
Phys Rev Lett ; 111(7): 072501, 2013 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-23992059

RESUMEN

The first spectroscopy of excited states in 52Ni (T(z)=-2) and 51Co (T(z)=-3/2) has been obtained using the highly selective two-neutron knockout reaction. Mirror energy differences between isobaric analogue states in these nuclei and their mirror partners are interpreted in terms of isospin nonconserving effects. A comparison between large-scale shell-model calculations and data provides the most compelling evidence to date that both electromagnetic and an additional isospin nonconserving interactions for J=2 couplings, of unknown origin, are required to obtain good agreement.

15.
Endoscopy ; 45(4): 265-71, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23322477

RESUMEN

BACKGROUND AND STUDY AIMS: Acute colorectal obstruction (ACO) often accompanies colorectal cancer (CRC) and requires urgent treatment, but achieving elective laparoscopy-assisted colectomy (LAC) is difficult in this setting. The aim of the current study was to assess the clinical outcomes of a transanal tube (Dennis colorectal tube [DCT]) for CRC with ACO, focusing in particular on the impact of the DCT on subsequent elective LAC. PATIENTS AND METHODS: Among 1142 patients who underwent surgery for CRC between January 2007 and December 2011, 92 patients with ACO were identified retrospectively. Of these 92 patients, the DCT procedure was performed in 66 patients who fulfilled the indications for DCT, and these patients were included in the study. RESULTS: All 66 patients presented with complete obstruction. Technical and clinical success rates for DCT were 93.9 % and 86.4 %, respectively. Perforation after DCT occurred in 4.5 % and the mortality rate was 1.5 %. The rate of LAC was 48.5 %, and the rate of primary stoma was 13.6 %. For curative stage II/III CRC with ACO, DCT resulted in a primary stoma rate of 13.6 %, a one-stage surgery rate of 90.9 %, a LAC rate of 50.0 %, and a 3-year survival rate of 73.1 %. For stage II/III CRC cases with clinical success by DCT, the one-stage surgery rate was 97.4 % and the LAC rate was 56.4 %. CONCLUSIONS: DCT achieved a high rate of clinical success and enabled safe one-stage surgery and LAC for CRC with ACO. DCT followed by LAC is proposed as a promising non-invasive strategy for CRC with ACO.


Asunto(s)
Neoplasias Colorrectales/cirugía , Drenaje/métodos , Obstrucción Intestinal/cirugía , Perforación Intestinal/etiología , Intubación Gastrointestinal/métodos , Adulto , Anciano , Anciano de 80 o más Años , Canal Anal , Colectomía , Neoplasias Colorrectales/complicaciones , Neoplasias Colorrectales/patología , Colostomía , Drenaje/instrumentación , Femenino , Humanos , Obstrucción Intestinal/etiología , Obstrucción Intestinal/patología , Intubación Gastrointestinal/efectos adversos , Estimación de Kaplan-Meier , Laparoscopía , Masculino , Persona de Mediana Edad , Cuidados Preoperatorios , Estudios Retrospectivos , Estadísticas no Paramétricas , Adulto Joven
16.
Int J Obstet Anesth ; 53: 103620, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36634449

RESUMEN

BACKGROUND: The influence of sugammadex exposure during pregnancy on progesterone withdrawal and miscarriage is unknown. We aimed to compare the fetal outcomes in pregnant patients who had undergone non-obstetric surgery with and without sugammadex. METHODS: We retrospectively reviewed the medical charts of pregnant women who underwent non-obstetric surgery at three tertiary perinatal care centers in Japan from January 2013 to December 2020. The women were divided into those who received general anesthesia with sugammadex (GA with SGX) and those who received general anesthesia without sugammadex (GA without SGX). We compared miscarriages and preterm births within four weeks after surgery. RESULTS: Among the 124 women, 73 and 51 were included in the GA with SGX and GA without SGX groups, respectively. The two groups showed no differences in the rate of miscarriages or preterm births (3.0 % vs 4.3 %; odds ratio 1.42, 95 % confidence interval 0.19 to 10.47; P = 1.00). The SGX and no SGX groups were missing outcomes for 8.2 % and 7.8 % of cases, respectively. CONCLUSIONS: Having GA with SGX or GA without SGX did not result in different rates of miscarriage or preterm birth within four weeks after the procedure. These findings do not exclude a potential association between sugammadex exposure during pregnancy and adverse pregnancy outcomes. Missing data may have obscured possible adverse outcomes from sugammadex exposure.


Asunto(s)
Aborto Espontáneo , Nacimiento Prematuro , Humanos , Femenino , Recién Nacido , Embarazo , Sugammadex , Estudios Retrospectivos , Nacimiento Prematuro/epidemiología , Nacimiento Prematuro/inducido químicamente , Resultado del Embarazo , Neostigmina/efectos adversos
17.
Phys Rev Lett ; 109(20): 202502, 2012 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-23215475

RESUMEN

The interaction of an E/A=70-MeV (7)Be beam with a Be target was used to populate levels in (6)Be following neutron knockout reactions. The three-body decay of the ground and first excited states into the α+p+p exit channel were detected in the High Resolution Array. Precise three-body correlations extracted from the experimental data allowed us to obtain insight into the mechanism of the three-body democratic decay. The correlation data are in good agreement with a three-cluster-model calculation and thus validate this theoretical approach over a broad energy range.

18.
Phys Rev Lett ; 108(12): 122501, 2012 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-22540576

RESUMEN

We present a novel technique for studying the quenching of shell gaps in exotic isotopes. The method is based on extracting Gamow-Teller (ΔL=0, ΔS=1) transition strengths [B(GT)] to low-lying states from charge-exchange reactions at intermediate beam energies. These Gamow-Teller strengths are very sensitive to configuration mixing between cross-shell orbitals, and this technique thus provides an important complement to other tools currently used to study cross-shell mixing. This work focuses on the N=8 shell gap. We populated the ground and 2.24 MeV 0+ states in 12Be using the 12B(1+) (7Li, 7Be) reaction at 80 MeV/u in inverse kinematics. Using the ground-state B(GT) value from ß-decay measurements (0.184±0.007) as a calibration, the B(GT) for the transition to the second 0+ state was determined to be 0.214±0.051. Comparing the extracted Gamow-Teller strengths with shell-model calculations, it was determined that the wave functions of the first and second 0+ states in 12Be are composed of 25±5% and 60±5% (0s)4(0p)8 configurations, respectively.

19.
Anaesthesia ; 67(8): 881-4, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22506698

RESUMEN

We compared the Pentax Airway Scope(TM) with the Airtraq(TM) optical laryngoscope in an infant manikin. Twenty-three anaesthetists randomly performed tracheal intubation: at rest, (a) with the Airway Scope and (b) with the Airtraq; and during chest compressions, (c) with the Airway Scope and (d) with the Airtraq. The success rate, modified Cormack and Lehane classification for glottic view, time taken to view the glottis, and time to place the tracheal tube were recorded. There was no difference in intubation success rate or quality of glottic view between the two devices. The median (IQR [range]) time taken to obtain a view of the glottis was 4.5 (3.7-6.4 [1.8-14.0]) s using the Airway Scope compared with 7.1 (5.5-9.6 [3.3-12.0]) s using the Airtraq (p = 0.001), and to successful placement of the tracheal tube was 8.3 (6.8-9.4 [3.7-20.7]) s using the Airway Scope compared with 11.2 (10.4-13.8 [4.9-23.7]) s using the Airtraq (p = 0.001). During chest compressions, the median (IQR [range]) time taken to view the glottis was 5.1 (4.0-7.2 [2.0-12.4]) s using the Airway Scope compared with 7.5 (5.0-13.2 [4.2-26.4]) s using the Airtraq (p = 0.006), and to successful placement of the tracheal tube was 9.5 (6.6-13.7 [4.5-16.2]) s using the Airway Scope compared with 11.7 (9.1-18.1 [6.2-37.4]) s using the Airtraq (p = 0.022). We conclude that both devices provided good quality views of the glottis and successful tracheal intubation in an infant manikin both at rest and during external chest compressions. Use of the Airway Scope resulted in a shorter time to view the glottis and perform successful tracheal intubation compared with the Airtraq.


Asunto(s)
Intubación Intratraqueal/instrumentación , Laringoscopios , Maniquíes , Humanos , Lactante
20.
Eur J Paediatr Dent ; 13(1): 19-24, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22455523

RESUMEN

AIM: Primary teeth undergo physiological root resorption during the transition to permanent dentition. The aim of this study was to assess the potential use of screw posts in core build-up for primary teeth while adequately retaining the crown restoration and allowing smooth physiological root resorption. METHODS: To determine whether biodegradable polymers such as polyglycolic acid (PGA) and poly-L-lactic acid (PLLA) were appropriate as post materials, bending strength test and bending elastic modulus test were performed according to ISO standards. The prepared screw posts were immersed in 0.01 mol/L phosphate-buffered saline at 37 degrees Celsius, and changes due to hydrolysis were observed. Results In the bending strength test and bending elastic modulus test, PGA and PLLA showed similar values to composite resins used for core build-up. Although both showed adequate hydrolysis, the hydrolysis rate of PGA was higher than that of PLLA. CONCLUSION: PGA and PLLA may be suitable as biodegradable screw posts for primary teeth because they have appropriate strength and hydrolysis ability.


Asunto(s)
Materiales Dentales/química , Poliésteres/química , Ácido Poliglicólico/química , Técnica de Perno Muñón/instrumentación , Diente Primario/patología , Implantes Absorbibles , Materiales Biocompatibles/química , Resinas Compuestas/química , Módulo de Elasticidad , Humanos , Hidrólisis , Ensayo de Materiales , Metacrilatos/química , Docilidad , Cementos de Resina/química , Resorción Radicular/fisiopatología , Cloruro de Sodio/química , Estrés Mecánico , Temperatura
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