Shedding Light on the Origin of

Asymptotic giant branch stars are responsible for the production of most of the heavy isotopes beyond Sr observed in the solar system. Among them, isotopes shielded from the r-process contribution by their stable isobars are defined as s-only nuclei. For a long time the abundance of ^{204}Pb, the heaviest s-only isotope, has been a topic of debate because state-of-the-art stellar models appeared to systematically underestimate its solar abundance. Besides the impact of uncertainties from stellar models and galactic chemical evolution simulations, this discrepancy was further obscured by rather divergent theoretical estimates for the neutron capture cross section of its radioactive precursor in the neutron-capture flow, ^{204}Tl (t_{1/2}=3.78 yr), and by the lack of experimental data on this reaction. We present the first ever neutron capture measurement on ^{204}Tl, conducted at the CERN neutron time-of-flight facility n_TOF, employing a sample of only 9 mg of ^{204}Tl produced at the Institute Laue Langevin high flux reactor. By complementing our new results with semiempirical calculations we obtained, at the s-process temperatures of kT≈8 keV and kT≈30 keV, Maxwellian-averaged cross sections (MACS) of 580(168) mb and 260(90) mb, respectively. These figures are about 3% lower and 20% higher than the corresponding values widely used in astrophysical calculations, which were based only on theoretical calculations. By using the new ^{204}Tl MACS, the uncertainty arising from the ^{204}Tl(n,γ) cross section on the s-process abundance of ^{204}Pb has been reduced from ∼30% down to +8%/-6%, and the s-process calculations are in agreement with the latest solar system abundance of ^{204}Pb reported by K. Lodders in 2021.

Measurement of the

^{140}Ce(n,γ) is a key reaction for slow neutron-capture (s-process) nucleosynthesis due to being a bottleneck in the reaction flow. For this reason, it was measured with high accuracy (uncertainty ≈5%) at the n_TOF facility, with an unprecedented combination of a high purity sample and low neutron-sensitivity detectors. The measured Maxwellian averaged cross section is up to 40% higher than previously accepted values. Stellar model calculations indicate a reduction around 20% of the s-process contribution to the Galactic cerium abundance and smaller sizeable differences for most of the heavier elements. No variations are found in the nucleosynthesis from massive stars.

74 Ge( n , γ ) cross section below 70 keV measured at n_TOF CERN.

Neutron capture reaction cross sections on 74 Ge are of importance to determine 74 Ge production during the astrophysical slow neutron capture process. We present new resonance data on 74 Ge( n , γ ) reactions below 70 keV neutron energy. We calculate Maxwellian averaged cross sections, combining our data below 70 keV with evaluated cross sections at higher neutron energies. Our stellar cross sections are in agreement with a previous activation measurement performed at Forschungszentrum Karlsruhe by Marganiec et al., once their data has been re-normalised to account for an update in the reference cross section used in that experiment.

Neutron Capture on the s-Process Branching Point

The neutron capture cross sections of several unstable nuclides acting as branching points in the s process are crucial for stellar nucleosynthesis studies. The unstable ^{171}Tm (t_{1/2}=1.92 yr) is part of the branching around mass A∼170 but its neutron capture cross section as a function of the neutron energy is not known to date. In this work, following the production for the first time of more than 5 mg of ^{171}Tm at the high-flux reactor Institut Laue-Langevin in France, a sample was produced at the Paul Scherrer Institute in Switzerland. Two complementary experiments were carried out at the neutron time-of-flight facility (n_TOF) at CERN in Switzerland and at the SARAF liquid lithium target facility at Soreq Nuclear Research Center in Israel by time of flight and activation, respectively. The result of the time-of-flight experiment consists of the first ever set of resonance parameters and the corresponding average resonance parameters, allowing us to make an estimation of the Maxwellian-averaged cross sections (MACS) by extrapolation. The activation measurement provides a direct and more precise measurement of the MACS at 30 keV: 384(40) mb, with which the estimation from the n_TOF data agree at the limit of 1 standard deviation. This value is 2.6 times lower than the JEFF-3.3 and ENDF/B-VIII evaluations, 25% lower than that of the Bao et al. compilation, and 1.6 times larger than the value recommended in the KADoNiS (v1) database, based on the only previous experiment. Our result affects the nucleosynthesis at the A∼170 branching, namely, the ^{171}Yb abundance increases in the material lost by asymptotic giant branch stars, providing a better match to the available pre-solar SiC grain measurements compared to the calculations based on the current JEFF-3.3 model-based evaluation.

Does the association between substance use and sexual risk behaviors among high school students vary by sexual identity?

OBJECTIVE: Limited information exists on whether associations between substance use behaviors (SUBs) and sexual risk behaviors (SRBs) vary by sexual identity. METHODS: Data from the 2015 national Youth Risk Behavior Survey (n = 15,624), were analyzed to assess associations between SUBs (cigarette smoking, alcohol use, binge drinking, marijuana use, prescription drug misuse, injection drug use, illicit drug use) and SRBs (sexual activity, number of partners, condom use). Logistic regression models calculated adjusted prevalence ratios (aPR), stratified by sexual identity, and interaction effects for sexual identity were introduced to models to determine if associations varied by sexual identity. RESULTS: All SUBs had significant associations with current sexual activity and 4+ sexual partners for both heterosexual and LGB students. No condom use during last sexual intercourse was significantly associated with all SUBs except alcohol use among heterosexual students, while no condom use was only significantly associated with injection drug use among LGB students. Associations between current sexual activity and SUBs were significantly stronger among heterosexual compared to LGB students for smoking (aPR = 2.39;95% CI:2.15,2.65 vs aPR = 1.49;95% CI:1.14,1.95), marijuana use (2.41;2.15,2.71 vs 1.86;1.58,2.19) and prescription drug misuse (2.10;1.93,2.28 vs 1.60;1.28,2.00). Associations between no condom use and SUBs were significantly stronger for heterosexual compared to LGB students only for smoking (1.32;1.16,1.50 vs 0.96;0.73,1.25) and marijuana use (1.22;1.07,1.38 vs 0.90;0.72,1.12). CONCLUSIONS: The relationship between most SUBs and SRBs did not vary significantly by sexual identity. These findings underscore the importance coordinating school-based programs to prevent substance use and promote sexual health.

University of Lodz an electron spectrometer--a new conversion-electron spectrometer for "in-beam" measurements.

The designed and constructed at the University of Lodz an electron spectrometer is devoted to "in-beam" measurements. The apparatus is characterized by high efficiency up to 9%, good energy resolution (FWHM = 5 keV at 482 keV) and, what is very important good suppression of delta electrons, positrons, and photons emitted by the targets. This achievement was obtained using a combination of magnetic field in two different layouts: perpendicular and parallel to the axis of the spectrometer being orthogonal to the beamline. The conversion-electron spectrometer coupled to the EAGLE array was successfully tested in an "in-beam" measurement.

Neutron capture cross section of unstable 63Ni: implications for stellar nucleosynthesis.

The 63Ni(n,γ) cross section has been measured for the first time at the neutron time-of-flight facility n_TOF at CERN from thermal neutron energies up to 200 keV. In total, capture kernels of 12 (new) resonances were determined. Maxwellian averaged cross sections were calculated for thermal energies from kT=5-100 keV with uncertainties around 20%. Stellar model calculations for a 25M⊙ star show that the new data have a significant effect on the s-process production of 63Cu, 64Ni, and 64Zn in massive stars, allowing stronger constraints on the Cu yields from explosive nucleosynthesis in the subsequent supernova.

Neutron cross-sections for next generation reactors: new data from n_TOF.

In 2002, an innovative neutron time-of-flight facility started operation at CERN: n_TOF. The main characteristics that make the new facility unique are the high instantaneous neutron flux, high resolution and wide energy range. Combined with state-of-the-art detectors and data acquisition system, these features have allowed to collect high accuracy neutron cross-section data on a variety of isotopes, many of which radioactive, of interest for Nuclear Astrophysics and for applications to advanced reactor technologies. A review of the most important results on capture and fission reactions obtained so far at n_TOF is presented, together with plans for new measurements related to nuclear industry.

Oxygen and steroid concentrations in preovulatory follicles of lactating dairy cows exposed to acute heat stress.

Maternal heat stress reduces oocyte competence for fertilization and post-fertilization development, but the mechanism is unknown. The present experiment investigated two potential mechanisms: (1) reduced oxygen delivery to the preovulatory follicle (due to increased thermoregulatory vascular perfusion of skin and respiratory tract); (2) reduced follicular steroid synthesis. These hypotheses were tested by measuring the fractional concentration of oxygen and concentrations of estradiol-17beta and progesterone in follicular fluid of the preovulatory follicle of lactating Holstein cows. Estrous cycles were synchronized using GnRH on Day -9 and PGF(2alpha) on Day -2. On Day 0, all cows without a CL and with a large preovulatory follicle were assigned to control or heat stress treatments for 1d (beginning at 1030 h). Between 4 and 6 h after treatment (1430-1630 h), follicular fluid was aspirated by transvaginal puncture, and fractional oxygen concentration in follicular fluid of the dominant follicle was determined with a fluorometric fiber-optic oxygen sensor. There was no significant effect of heat stress on follicular fluid P(O2) or concentrations of estradiol-17beta or progesterone among cows that had follicular fluid steroid concentrations considered typical of a preovulatory follicle. Follicular oxygen concentration was 6.9+/-0.4% for control cows and 7.3+/-0.3% for heat-stressed cows. Oxygen concentration tended to be inversely correlated to follicular diameter (P=0.09). In conclusion, it was unlikely that reduced oocyte competence due to acute heat stress was caused by reductions in follicular concentrations of oxygen, estradiol-17beta, or progesterone.

Neutron capture cross section measurement of 151Sm at the CERN neutron time of flight facility (n_TOF).

The151Sm(n,gamma)152Sm cross section has been measured at the spallation neutron facility n_TOF at CERN in the energy range from 1 eV to 1 MeV. The new facility combines excellent resolution in neutron time-of-flight, low repetition rates, and an unsurpassed instantaneous luminosity, resulting in rather favorable signal/background ratios. The 151Sm cross section is of importance for characterizing neutron capture nucleosynthesis in asymptotic giant branch stars. At a thermal energy of kT=30 keV the Maxwellian averaged cross section of this unstable isotope (t(1/2)=93 yr) was determined to be 3100+/-160 mb, significantly larger than theoretical predictions.

[The study of the influence of aminoglycoside antibiotics on the hearing organs in children]. / Badania nad wplywem antybiotyków aminoglikozydowych na narzad sluchu u dzieci.

The paper presents results of audiologic assessments hearing examinations in 19 children that received aminoglycosides in cases of pneumonias, meningitis and sepsis. Examination of hearing acuity with otoscopic assessment of the ears, tympanometry, ABR and acoustic otoemission were performed before, directly after infusion and after completion of treatment. After a laryngological examination and of the hearing acuity, tympanometry and the ABR the authors have concluded the normal state of the hearing organ. Only in the examination of the acoustic otoemission produced during the treatment it was found the amplitude was flattened or there was no otoeimssion for some individual frequencies in relation to records taken before the treatment. The authors emphasize that among risk factors of ototoxic effect of some medicines are of importance the following: patient's age, uncontrolled increase in blood drug concentration, increase in daily dosage, cumulation of the drug in the organism, prolonged treatment with the drug.

Evaluation of the Alcopatch, a transdermal dosimeter for monitoring alcohol consumption.

BACKGROUND: The Alcopatch is an improved transdermal dosimeter for the measurement of alcohol consumption, by detection of ethanol in fluid excreted from the skin. The device is worn as a band around the ankle and provides a visual signal in the event of tampering. METHODS: Fourteen volunteers wore duplicate Alcopatches for a period of 7 or 8 days, while keeping a written record of their beverage alcohol consumption. Ethanol concentration in the Alcopatch was measured by gas chromatography and correlated with self-reported consumption. RESULTS: All alcohol consumption in excess of 0.25 g/kg/day resulted in measurable levels of ethanol in the Alcopatch. A positive correlation was observed between the reported consumption of ethanol (in g/kg/day) and the concentration of ethanol in the Alcopatch (square root, in mg/dl) (y = 0.91x + 0.28, r = 0.61) in 12 of 14 subjects. CONCLUSIONS: The Alcopatch detected the consumption of beverage alcohol with high sensitivity and specificity over a period of 7 to 8 days and may be useful for the study of target populations.

[Anterior-medial rotatory instability of the knee joint. Follow up results of surgical treatment]. / Przednio-przysrodkowa obrotowa niestabilnosc stawu kolanowego. Odlegle wyniki leczenia operacyjnego.

In the years 1979-1988 65 patients (62 men and 3 women) with rotary anterior-medial instability of the knee were treated surgically. The average age was 34 years. The cause of injuries (65%) were accidents during work in mines of pit-coal. 52 patients were treated surgically in the period of 7 days after the accident. The remaining 13 ones were operated on after the period of 6 weeks. In the group of patients operated on immediately the most frequently applied procedure was the suture according to O'Donoughe of the injured ligaments and shift of the goose foot according to Slocum and Larson. But when the anterior crucial ligament was broken in the shape of a "brush", its reconstruction was formally made according to Jones. For patients with chronic instability extra-articular plastic operations were performed i.e. shift of the semi-tendinous muscle and shift of the goose foot, as well as intra-articular--in case of injury of the anterior crucial ligament. The period of observation was from 4 to 12 years. Better results were obtained in patients operated on immediately: good result--62%, satisfactory--32% and bad--6%. For all patients with chronic instability the obtained results were only satisfactory.

[The application of chorioallantois membranes of chicken embryos for the virulence determination of Nocardia asteroides (author's transl)]. / Uber die Verwendung der Choriollantoismembran von Hühnerembryonen zur Virulenzbestimmung von Nocardia asteroides

The pathogenicity of Nocardia asteroides and other strains of different Nocardia species against chicken embryos was investigated. The strains were inoculated on the chorioallantois membrane of embryonated eggs and the resulting lesions were judged. 55 Nocardia asteroides strains and some strains of the species N. brasiliensis, N. leishmanii, N. caviae, N. (Actinomadura) madurae, N. caprae, N. rubra, N. pellegrini, N. corallina and N. polychromogenes were studied. 47 strains of the species N. asteroides were pathogenic, 2 apathogenic and 6 strains showed doubtful results. All the investigated 5 strains of the species N. brasiliensis, N. leishmanii, N. caviae and N. (Actinomadura) madurae, provoked typical lesions on the chorioallantois membrane. The other investigated strains were apathogenic. With this, described test it is possible to distinguish between pathogenic and apathogenic Nocardia strains, which is indeed important for the diagnosis of Nocardia infection.

[The morphology of a nocardia asteroides-bacteriophage (author's transl)]. / Uber die Morphologie eines Nocardia asteroides-Bakteriophagen

The morphology of a new bacteriophage isolated from Nocardia asteroides has been investigated by negative staining. The percent results suggest a model which is valid for many phages. The head of the bacteriophage has the shape of an icosaeder with a diameter of about 420 AU. It probably contains a spherical core which is surrounded by a capsid of 15 AU thickness. A flexible non-contractible tail is connected by a collar to one of the head's edges. Its length is about 1400 AU and its diameter 60 AU. The tail shows a cross striation with a periodicity of 40 AU and a channel. At the distal side it passes over into a conical end structure. Conforming this morphological criteria the new bacteriophage belongs to the group B of Bradley.

[Nocardia pellegrini: III. An attempt of phage typing(author's transl)]. / Nocardia pellegrini: III. Versuch einer Phagentypisierung

The typing of Nocardia pellegrini with different Nocardia-phages was studied. The investigation included 25 Nocardia pellegrini strains, 19 strains of different Nocardia species and also strains of different species of mycobacteria. It could be stated that phages typical for Nocardia pellegrini were also active against other fast fragmentating Nocardia species, such as Nocardia corallina or Nocardia rubra. However, they did not attack Nocardia asteroides or strains of mycobacteria. Phages typical for mycobacteria or for Nocardia asteroides did not lysate the fast fragmentating nocardia (Table 1 and 2). Mutants of one Nocardia pellegrini phage could be isolated which showed a broader host range than the parent phage (Table 1 and 2). Some lysogenic strains of Nocardia pellegrini with a changed phage sensitivity could be isolated after action of the phages (Table 3). The taxonomical position of Nocardia pellegrini and Nocardia rubra is discussed.