Statistical (n, γ ) cross section model comparison for short-lived nuclei.

Neutron-capture cross sections of neutron-rich nuclei are calculated using a Hauser-Feshbach model when direct experimental cross sections cannot be obtained. A number of codes to perform these calculations exist, and each makes different assumptions about the underlying nuclear physics. We investigated the systematic uncertainty associated with the choice of Hauser-Feshbach code used to calculate the neutron-capture cross section of a short-lived nucleus. The neutron-capture cross section for 73 Zn (n, γ ) 74 Zn was calculated using three Hauser-Feshbach statistical model codes: TALYS, CoH, and EMPIRE. The calculation was first performed without any changes to the default settings in each code. Then an experimentally obtained nuclear level density (NLD) and γ -ray strength function ( γ SF ) were included. Finally, the nuclear structure information was made consistent across the codes. The neutron-capture cross sections obtained from the three codes are in good agreement after including the experimentally obtained NLD and γ SF , accounting for differences in the underlying nuclear reaction models, and enforcing consistent approximations for unknown nuclear data. It is possible to use consistent inputs and nuclear physics to reduce the differences in the calculated neutron-capture cross section from different Hauser-Feshbach codes. However, ensuring the treatment of the input of experimental data and other nuclear physics are similar across multiple codes requires a careful investigation. For this reason, more complete documentation of the inputs and physics chosen is important. Supplementary Information: The online version contains supplementary material available at 10.1140/epja/s10050-023-00920-0.

Publisher's Note: Experimental Neutron Capture Rate Constraint Far from Stability [Phys. Rev. Lett. 116, 242502 (2016)].

This corrects the article DOI: 10.1103/PhysRevLett.116.242502.

Experimental Neutron Capture Rate Constraint Far from Stability.

Nuclear reactions where an exotic nucleus captures a neutron are critical for a wide variety of applications, from energy production and national security, to astrophysical processes, and nucleosynthesis. Neutron capture rates are well constrained near stable isotopes where experimental data are available; however, moving far from the valley of stability, uncertainties grow by orders of magnitude. This is due to the complete lack of experimental constraints, as the direct measurement of a neutron-capture reaction on a short-lived nucleus is extremely challenging. Here, we report on the first experimental extraction of a neutron capture reaction rate on ^{69}Ni, a nucleus that is five neutrons away from the last stable isotope of Ni. The implications of this measurement on nucleosynthesis around mass 70 are discussed, and the impact of similar future measurements on the understanding of the origin of the heavy elements in the cosmos is presented.

Strong Neutron-γ Competition above the Neutron Threshold in the Decay of

The ß-decay intensity of ^{70}Co was measured for the first time using the technique of total absorption spectroscopy. The large ß-decay Q value [12.3(3) MeV] offers a rare opportunity to study ß-decay properties in a broad energy range. Two surprising features were observed in the experimental results, namely, the large fragmentation of the ß intensity at high energies, as well as the strong competition between γ rays and neutrons, up to more than 2 MeV above the neutron-separation energy. The data are compared to two theoretical calculations: the shell model and the quasiparticle random phase approximation (QRPA). Both models seem to be missing a significant strength at high excitation energies. Possible interpretations of this discrepancy are discussed. The shell model is used for a detailed nuclear structure interpretation and helps to explain the observed γ-neutron competition. The comparison to the QRPA calculations is done as a means to test a model that provides global ß-decay properties for astrophysical calculations. Our work demonstrates the importance of performing detailed comparisons to experimental results, beyond the simple half-life comparisons. A realistic and robust description of the ß-decay intensity is crucial for our understanding of nuclear structure as well as of r-process nucleosynthesis.

Evidence for partial dynamical symmetries in atomic nuclei.

Symmetries in nature offer very simple descriptions of complex systems. Partial Dynamical Symmetries (PDS) can considerably broaden their relevance. To present the first extensive test of a PDS for nuclei, we compare an SU(3) PDS to gamma to ground band B(E2) values for 47 deformed nuclei. The parameter-free PDS is found to be quite successful, but with characteristic discrepancies, suggesting that symmetry remnants are more pervasive than heretofore realized. Furthermore, the SU(3) PDS gives new insights into collective models (e.g., interacting boson approximation). If these reproduce the PDS, they reflect finite size effects, while differences from the PDS point to SU(3) configuration mixing.

Prenatal abnormal features of the fourth ventricle in Joubert syndrome and related disorders.

Joubert syndrome and related disorders (JSRD) are characterized by absence or underdevelopment of the cerebellar vermis and a malformed brainstem. This family of disorders is a member of an emerging class of diseases called ciliopathies. We describe the abnormal features of the brain, particularly the fourth ventricle, in seven fetuses affected by JSRD. In three cases abnormality of the fourth ventricle was isolated and in four cases there were associated malformations. The molar tooth sign (MTS) was always present and visible on two-dimensional ultrasound and, when performed, on three-dimensional ultrasound and magnetic resonance imaging. The fourth ventricle was always abnormal, in both axial and sagittal views, presenting pathognomonic deformities. It is important to identify JSRD, preferably prenatally or at least postnatally, due to its high risk of recurrence of about 25%. A detailed prenatal assessment of the fourth ventricle in several views may help to achieve this goal.

New precision measurements of the 235U(n,γ) cross section.

The neutron capture cross section of (235)U was measured for the neutron incident energy region between 4 eV and 1 MeV at the DANCE facility at the Los Alamos Neutron Science Center with an unprecedented accuracy of 2-3% at 1 keV. The new methodology combined three independent measurements. In the main experiment, a thick actinide sample was used to determine neutron capture and neutron-induced fission rates simultaneously. In the second measurement, a fission tagging detector was used with a thin actinide sample and detailed characteristics of the prompt-fission gamma rays were obtained. In the third measurement, the neutron scattering background was characterized using a sample of (208)Pb. The relative capture cross section was obtained from the experiment with the thick (235)U sample using a ratio method after the subtraction of the fission and neutron scattering backgrounds. Our result indicates errors that are as large as 30% in the 0.5-2.5 keV region, in the current knowledge of neutron capture as embodied in major nuclear data evaluations. Future modifications of these databases using the improved precision data given herein will have significant impacts in neutronics calculations for a variety of nuclear technologies.

Prenatal management of congenital infantile fibrosarcoma: unexpected outcome.

We report the case of a large leg tumor in a fetus at 36 weeks of gestation. The tumor's location, ultrasound characteristics and magnetic resonance imaging (MRI) findings enabled a prenatal diagnosis of congenital fibrosarcoma and allowed us to establish the prognosis. After multidisciplinary discussion, it was decided that the pregnancy should continue to 38 weeks, with surgery or neo-adjuvant chemotherapy scheduled after delivery. Unfortunately, the tumor unexpectedly burst in utero and the newborn died of the consequences of hemorrhagic shock, despite rapid amputation. Histological examination confirmed the nature of the tumor. The prognosis of congenital fibrosarcoma is generally good when there are no metastases. MRI is key to establishing a prenatal diagnosis. However, rupture of the tumor can result in fatal hemorrhaging and the pregnancy should be monitored closely before scheduled delivery.

[Ultrasonography of fetal esophagus: healthy appearance and prenatal diagnosis of a case of esophagus atresia with esotracheal fistula]. / Echographie de l'oesophage foetal: aspect physiologique et application au dépistage anténatal d'une atrésie oesophagienne.

The thoracic part of a fetal esophagus is generally overlooked by usual prenatal ultrasonography. However, screening it might improve the detection rate of esophageal malformations for which prenatal diagnosis remains far from accurate. In this article, we describe the technique which makes it possible to get a precise image of a fetal thoracic esophagus in its more sensitive part: between the trachea and the aorta. After describing the appearance of a healthy thoracic esophagus, we will show how this technique can be used for prenatal detection of esophagus malformations. For this purpose, we provide the case report of a prenatal diagnosis of esophagus atresia with esotracheal fistula.

[MRI of fetal GI tract]. / IRM du tube digestif foetal.

The fetal diagnosis of GI tract abnormalities may be improved by the use of MRI that is able to visualize the normal bowel, may characterize the nature and location of gastrointestinal abnormalities, detect severe malformations, demonstrate the bowel close to cystic or tumoral intra abdominal structures. Our personal experience and recent data of the literature are reported.

Cytokine induction in hairless mouse and rat skin after topical application of the immune response modifiers imiquimod and S-28463.

ALDARA (imiquimod cream 5%) recently became available for the treatment of genital and perianal warts; however, the topical mechanism of action of imiquimod is not fully understood. Imiquimod, and its analogs R-842, S-27609, and S-28463, are potent anti-viral and anti-tumor agents in animal models. Much of the biologic activity of these compounds can be attributed to the induction of cytokines, including interferon-alpha, tumor necrosis factor-alpha, interleukins-1, -6, -8, and others. This study was performed to characterize the response of mice and rats to topical application of imiquimod and S-28463 and also to evaluate these agents in cultures of murine and human skin cells. Topical administration of imiquimod or S-28463 to the flanks of hairless mice and rats leads to increases in local concentrations of interferon and tumor necrosis factor in the skin. The concentrations of interferon and tumor necrosis factor were higher at the site of drug application than in skin from the contralateral flank or skin from untreated animals. Interferon-alpha mRNA levels were also elevated in the skin of mice after topical application of either imiquimod or S-28463. In vitro, both imiquimod and S-28463 induced increases in interferon and tumor necrosis factor in cultures of cells isolated from hairless mouse skin. Imiquimod also increased interleukin-8 concentrations in human keratinocyte and fibroblast cultures, whereas S-28463 induced increases in tumor necrosis factor in fibroblast cultures. These results demonstrate that imiquimod and S-28463 stimulate production of cytokines in the skin after topical application, which may play a major role in its activity in genital wart patients.

[Neuroblastoma, factor of early decompensation of tetralogy of Fallot]. / Neuroblastome facteur de décompensation précoce d'une tétralogie de Fallot.

The authors report the case of a tetralogy of Fallot associated with a neuroblastoma secreting large quantities of noradrenaline. Anoxic decompensation of the tetralogy of Fallot occurred early at the age of 4 months with cyanotic crises associated with an impression of abdominal pain. A systemic-pulmonary anastomosis was performed and the cyanosis regressed but the crises persisted and investigations showed the presence of a neuroblastoma. The tumour was treated by surgery and chemotherapy and has not recurred after 2 years' follow-up. Complete repair of the tetralogy of Fallot was performed secondarily at the age of 2. In this case, the high concentration of circulating catecholamines was probably a factor of early decompensation of the tetralogy of Fallot by infundibular spasm. A review of the literature revealed 26 cases of cardiac disease with a peripheral neurogenic tumour. Two pathogenic mechanisms are suggested: an embryological abnormality of cardiac cell migration from the neural crest and chronic stimulation of neuroblastic cells by chronic hypoxia.

[Brain sonography in 2001. Evaluation of macrocrania in the infant]. / L'échographie cérébrale en l'an 2001. Le point sur l'exploration d'une macrocrânie du nourrisson.

Transfontanelle sonography has become a routine imaging modality to assess infants with macrocrania: detection of hydrocephalus and diagnosis of its underlying etiology, detection and mapping of extra-axial collections, value of Doppler US for diagnosis of intracranial lesions, hemodynamic evaluation using pulsed Doppler imaging.

[Localized hypertrophic neuropathy (LHN) of the brachial plexus: diagnosis and presurgical evaluation with MRI]. / Neuropathie hypertrophique localisée (NHL) du plexus brachial: diagnostic et bilan préoperatoire par l'IRM.

The authors report a case of localized hypertrophic neuropathy diagnosed by MRI. This 10-year-old girl presented with painless progressive deltoid atrophy. Electrodiagnostic studies demonstrated chronic denervation. An MRI performed with T1, T2, T1 with gadolinium and fat saturation sequences showed a linear 5-cm long segment of hypertrophic brachial plexus cord, with moderate high T2, intermediate T1 signal, and marked post-Gadolinium enhancement. Progressive improvement followed surgical resection with nerve graft repair. Histological study confirmed LHN (perineurial cell proliferation), a rare cause of peripheral neurological deficit. MRI findings may suggest LHN, that should be suspected as well as peripheral nerve compression or tumor; inflammatory neuritis and idiopathic lesion (with normal MRI findings) remain a diagnosis of exclusion. MR aids in the precise localization of the lesion before surgery.

[Discitis in small children (author's transl)]. / Les discites du petit enfant.

Discitis was diagnosed in 5 children under 3 years of age, the initial clinical manifestations being difficulty in walking and abdominal pains in one case. Diagnosis was not made before periods varying from 8 days to 3 months, and no etiological basis for the disease was discovered. Pinching of the disc was always present in the first radiographic image, and the vertebral plate was ill-defined in 3 cases. Repeat radiological examinations were carried out in 3 children after 6 months, 2 and 5 years respectively. There was partial restauration of the disc space in 2 cases; the last one presented signs of late collapse after early recuperation. Early perilesional bone sclerosis was noted in 2 cases, while it was posterior and late in one child. There were no sequelae (fusion, vertebra plana, scoliosis). Two investigations are essential if a disc lesion is suspected: -- radiography of the spinal column, even if there are no disturbances in walking or abdominal pains. -- scintigraphy with technitium 99, which is the only means of establishing an early diagnosis.

[Early prenatal ultrasonographic diagnosis of fetus in fetu]. / Diagnostic précoce d'un foetus in fetu abdominal: sémiologie échographique.

Fetus in fetu is a very rare abnormality, and is secondary to a pathological diamniotic monochorionic pregnancy. Its discovery is usually postnatal. We report a case of prenatal diagnosis suspected at 16 gestation's week because of a voluminous omphalocele seen at 12 gestation's week.

[Fetal intraventricular hemorrhage caused by cerebral contusion, and with spontaneous remission. Contribution of MRI]. / Hémorragie intraventriculaire foetale par contusion cérébrale et résolution spontanée. Apport de l'IRM.

We report a case of fetal ventricular hemorrhage which occurred at 27.5 weeks gestation and caused by fetal brain contusion after a maternal traumatism. Ultrasound examination evidenced ventriculomegaly and an intraventricular clot which were confirmed by MRI. We discuss the interest of combining ultrasound and MRI of the fetal brain for the investigation and follow-up of fetal brain trauma. The patient gave birth to an eutrophic normal boy. The child is normal at 12 months follow-up.

[Role of cerebral echography in the diagnosis of aneurysms of the vein of Galen]. / Place de l'échographie cérébrale dans le diagnostic de l'anévrysme de la veine de Galien.

Cerebral ultrasound imaging by a transfontanelle approach is now a common investigation during the first year of life. This exploratory procedure is non-invasive, non-irradiating, requires no sedation and can be carried out at the infant's bedside. In addition, the classical apparatus can be completed by deep Doppler allowing deep cerebral vessels to be studied. Three cases are reported of aneurysm of Galen's ampulla detected by ultrasound imaging during the neonatal period. Images demonstrated the presence of an abnormal fluid mass in the region of Galen's ampulla, confirmed as of vascular origin by Doppler, and allowed assessment of degree of subjacent ventricular dilatation and possible secondary ischemic lesions. In massive neonatal forms this exploration may be sufficient since prognosis is poor, but in lesions of moderate size CT scan and angiographic examinations and perhaps MR imaging are required. This technique allows detection of this malformation in the fetus and could therefore influence therapy.

[Immunosuppressive effects of a new phenothiazine derivative]. / Les effets immunosuppresseurs d'un nouveau dérivé de la phénothiazine.

An original phenothiazine, CPTZ, was tested for its effects on the mouse immune system. Serum opsonic capacity, phagocyte and bactericidal activity of peritoneal macrophages, counts of splenic cells forming hemolysis plaques, and the number of survivors after experimental infection were recorded. The effects observed were compared with those produced by levamisole (a non-selective immunomodulator) and indometacin (an antiinflammatory drug with selective immunomodulator properties). The effects of CPTZ might be useful for the development of a new class of immunosuppressor drugs.

[Photophysical evaluation of photosensitization by various quinolones]. / Evaluation photophysique du pouvoir photosensibilisant de diverses quinolones.

An original physicochemical method is proposed for the evaluation of the photosensitizing activity of drugs in vitro. A Nuclear Magnetic Resonance (NMR) spectrum is recorded during light irradiation of drug solutions. The change in the intensity of the NMR lines under such conditions is termed the Photochemically Induced Dynamic Nuclear Polarization (Photo-CIDNP) effect. It is related to the formation of radical intermediates which may be involved in the in vivo photosensitization reactions (the so-called type-I photoreactions). Nine commercial quinolones were tested by this method: nalidixic, oxolinic, pipemidic and piromidic acids, rosoxacin, flumequine, enoxacin, pefloxacin and norfloxacin. Each quinolone was irradiated in alcoholic solutions in its UV absorption band (300-350 nm) in the absence or in the presence of a biological target chosen as a model: the amino-acid N-acetyltyrosine. The quinolones were classified in two groups in relation to the intensities of the observed CIDNP effects. Nalidixic and oxolinic acids, rosoxacin and flumequine are among the most potent photosensitizers.