Proton-Capture Rates on Carbon Isotopes and Their Impact on the Astrophysical

The ^{12}C/^{13}C ratio is a significant indicator of nucleosynthesis and mixing processes during hydrogen burning in stars. Its value mainly depends on the relative rates of the ^{12}C(p,γ)^{13}N and ^{13}C(p,γ)^{14}N reactions. Both reactions have been studied at the Laboratory for Underground Nuclear Astrophysics (LUNA) in Italy down to the lowest energies to date (E_{c.m.}=60 keV) reaching for the first time the high energy tail of hydrogen burning in the shell of giant stars. Our cross sections, obtained with both prompt γ-ray detection and activation measurements, are the most precise to date with overall systematic uncertainties of 7%-8%. Compared with most of the literature, our results are systematically lower, by 25% for the ^{12}C(p,γ)^{13}N reaction and by 30% for ^{13}C(p,γ)^{14}N. We provide the most precise value up to now of 3.6±0.4 in the 20-140 MK range for the lowest possible ^{12}C/^{13}C ratio that can be produced during H burning in giant stars.

Direct Measurement of the

One of the main neutron sources for the astrophysical s process is the reaction ^{13}C(α,n)^{16}O, taking place in thermally pulsing asymptotic giant branch stars at temperatures around 90 MK. To model the nucleosynthesis during this process the reaction cross section needs to be known in the 150-230 keV energy window (Gamow peak). At these sub-Coulomb energies, cross section direct measurements are severely affected by the low event rate, making us rely on input from indirect methods and extrapolations from higher-energy direct data. This leads to an uncertainty in the cross section at the relevant energies too high to reliably constrain the nuclear physics input to s-process calculations. We present the results from a new deep-underground measurement of ^{13}C(α,n)^{16}O, covering the energy range 230-300 keV, with drastically reduced uncertainties over previous measurements and for the first time providing data directly inside the s-process Gamow peak. Selected stellar models have been computed to estimate the impact of our revised reaction rate. For stars of nearly solar composition, we find sizeable variations of some isotopes, whose production is influenced by the activation of close-by branching points that are sensitive to the neutron density, in particular, the two radioactive nuclei ^{60}Fe and ^{205}Pb, as well as ^{152}Gd.

OPERA tau neutrino charged current interactions.

The OPERA experiment was designed to discover the vτ appearance in a vµ beam, due to neutrino oscillations. The detector, located in the underground Gran Sasso Laboratory, consisted of a nuclear photographic emulsion/lead target with a mass of about 1.25 kt, complemented by electronic detectors. It was exposed from 2008 to 2012 to the CNGS beam: an almost pure vµ beam with a baseline of 730 km, collecting a total of 1.8·1020 protons on target. The OPERA Collaboration eventually assessed the discovery of vµâ†’vτ oscillations with a statistical significance of 6.1 σ by observing ten vτ CC interaction candidates. These events have been published on the Open Data Portal at CERN. This paper provides a detailed description of the vτ data sample to make it usable by the whole community.

The baryon density of the Universe from an improved rate of deuterium burning.

Light elements were produced in the first few minutes of the Universe through a sequence of nuclear reactions known as Big Bang nucleosynthesis (BBN)1,2. Among the light elements produced during BBN1,2, deuterium is an excellent indicator of cosmological parameters because its abundance is highly sensitive to the primordial baryon density and also depends on the number of neutrino species permeating the early Universe. Although astronomical observations of primordial deuterium abundance have reached percent accuracy3, theoretical predictions4-6 based on BBN are hampered by large uncertainties on the cross-section of the deuterium burning D(p,γ)3He reaction. Here we show that our improved cross-sections of this reaction lead to BBN estimates of the baryon density at the 1.6 percent level, in excellent agreement with a recent analysis of the cosmic microwave background7. Improved cross-section data were obtained by exploiting the negligible cosmic-ray background deep underground at the Laboratory for Underground Nuclear Astrophysics (LUNA) of the Laboratori Nazionali del Gran Sasso (Italy)8,9. We bombarded a high-purity deuterium gas target10 with an intense proton beam from the LUNA 400-kilovolt accelerator11 and detected the γ-rays from the nuclear reaction under study with a high-purity germanium detector. Our experimental results settle the most uncertain nuclear physics input to BBN calculations and substantially improve the reliability of using primordial abundances to probe the physics of the early Universe.

Direct Capture Cross Section and the E_{p}=71 and 105 keV Resonances in the

The ^{22}Ne(p,γ)^{23}Na reaction, part of the neon-sodium cycle of hydrogen burning, may explain the observed anticorrelation between sodium and oxygen abundances in globular cluster stars. Its rate is controlled by a number of low-energy resonances and a slowly varying nonresonant component. Three new resonances at E_{p}=156.2, 189.5, and 259.7 keV have recently been observed and confirmed. However, significant uncertainty on the reaction rate remains due to the nonresonant process and to two suggested resonances at E_{p}=71 and 105 keV. Here, new ^{22}Ne(p,γ)^{23}Na data with high statistics and low background are reported. Stringent upper limits of 6×10^{-11} and 7×10^{-11} eV (90% confidence level), respectively, are placed on the two suggested resonances. In addition, the off-resonant S factor has been measured at unprecedented low energy, constraining the contributions from a subthreshold resonance and the direct capture process. As a result, at a temperature of 0.1 GK the error bar of the ^{22}Ne(p,γ)^{23}Na rate is now reduced by 3 orders of magnitude.

Erratum: Three New Low-Energy Resonances in the

This corrects the article DOI: 10.1103/PhysRevLett.115.252501.

Final Results of the OPERA Experiment on ν_{τ} Appearance in the CNGS Neutrino Beam.

The OPERA experiment was designed to study ν_{µ}→ν_{τ} oscillations in the appearance mode in the CERN to Gran Sasso Neutrino beam (CNGS). In this Letter, we report the final analysis of the full data sample collected between 2008 and 2012, corresponding to 17.97×10^{19} protons on target. Selection criteria looser than in previous analyses have produced ten ν_{τ} candidate events, thus reducing the statistical uncertainty in the measurement of the oscillation parameters and of ν_{τ} properties. A multivariate approach for event identification has been applied to the candidate events and the discovery of ν_{τ} appearance is confirmed with an improved significance level of 6.1σ. |Δm_{32}^{2}| has been measured, in appearance mode, with an accuracy of 20%. The measurement of the ν_{τ} charged-current cross section, for the first time with a negligible contamination from ν[over ¯]_{τ}, and the first direct evidence for the ν_{τ} lepton number are also reported.

Pregnancy and neonatal outcomes among a cohort of HIV-infected women in a large Italian teaching hospital: a 30-year retrospective study.

The primary study objective was to investigate three decades from 1985 to 2014 of changes in pregnancies among HIV-infected women. The secondary objective was to assess risk factors associated with preterm delivery and severe small-for-gestational-age (SGA) infants in HIV-infected women. A retrospective review of deliveries among pregnant HIV-infected women at the University of Genoa and IRCCS San Martino-IST in Genoa between 1985 and 2014 was performed. Univariate and multivariable analyses were used to study the variables associated with neonatal outcomes. Overall, 262 deliveries were included in the study. An increase in median age (26 years in 1985-1994 vs. 34 years in 2005-2014), in the proportion of foreigners (none in 1985-1994 vs. 27/70 (38·6%) in 2005-2014), and a decrease in intravenous drug use (75·2% (91/121) in 1985-1994 vs. 12·9% (9/70) in 2005-2014) among pregnant HIV-infected women was observed. Progressively, HIV infections were diagnosed sooner (prior to pregnancy in 80% (56/70) of women in the last decade). An increase in combined antiretroviral therapy (cART) prescription during pregnancy (50% (27/54) in 1995-2004 vs. 92·2% (59/64) in 2005-2014) and in HIV-RNA <50 copies/ml at delivery (19·2% (5/26) in 1995-2004 vs. 82·3% (53/64) in 2005-2014) was observed. The rate of elective caesarean section from 1985 to 1994 was 9·1%, which increased to 92·3% from 2004 to 2015. Twelve (10·1%) mother-to-child transmissions (MTCT) occurred in the first decade, and six (8·3%) cases occurred in the second decade, the last of which was in 2000. Preterm delivery (<37 weeks gestation) was 5% (6/121) from 1985 to 1994 and increased to 17·1% (12/70) from 2005 to 2014. In univariate and multivariable logistic regression analyses, advancing maternal age and previous pregnancies were associated with preterm delivery (odds ratio (OR) 2·7; 95% confidence intervals (CI) 1-7·8 and OR 2·6; 95% CI 1·1-6·7, respectively). In the logistic regression analysis, use of heroin or methadone was found to be the only risk factor for severe SGA (OR 3·1; 95% CI 1·4-6·8). In conclusion, significant changes in demographic, clinical and therapeutic characteristics of HIV-infected pregnant women have occurred over the last 30 years. Since 2000, MTCT has decreased to zero. An increased risk of preterm delivery was found to be associated with advancing maternal age and previous pregnancies but not with cART. The use of heroin or methadone has been confirmed as a risk factor associated with severe SGA.

Improved Direct Measurement of the 64.5 keV Resonance Strength in the

The ^{17}O(p,α)^{14}N reaction plays a key role in various astrophysical scenarios, from asymptotic giant branch stars to classical novae. It affects the synthesis of rare isotopes such as ^{17}O and ^{18}F, which can provide constraints on astrophysical models. A new direct determination of the E_{R}=64.5 keV resonance strength performed at the Laboratory for Underground Nuclear Astrophysics (LUNA) accelerator has led to the most accurate value to date ωγ=10.0±1.4_{stat}±0.7_{syst} neV, thanks to a significant background reduction underground and generally improved experimental conditions. The (bare) proton partial width of the corresponding state at E_{x}=5672 keV in ^{18}F is Γ_{p}=35±5_{stat}±3_{syst} neV. This width is about a factor of 2 higher than previously estimated, thus leading to a factor of 2 increase in the ^{17}O(p, α)^{14}N reaction rate at astrophysical temperatures relevant to shell hydrogen burning in red giant and asymptotic giant branch stars. The new rate implies lower ^{17}O/^{16}O ratios, with important implications on the interpretation of astrophysical observables from these stars.

Discovery of τ Neutrino Appearance in the CNGS Neutrino Beam with the OPERA Experiment.

The OPERA experiment was designed to search for ν_{µ}→ν_{τ} oscillations in appearance mode, i.e., by detecting the τ leptons produced in charged current ν_{τ} interactions. The experiment took data from 2008 to 2012 in the CERN Neutrinos to Gran Sasso beam. The observation of the ν_{µ}→ν_{τ} appearance, achieved with four candidate events in a subsample of the data, was previously reported. In this Letter, a fifth ν_{τ} candidate event, found in an enlarged data sample, is described. Together with a further reduction of the expected background, the candidate events detected so far allow us to assess the discovery of ν_{µ}→ν_{τ} oscillations in appearance mode with a significance larger than 5σ.

Three New Low-Energy Resonances in the

The ^{22}Ne(p,γ)^{23}Na reaction takes part in the neon-sodium cycle of hydrogen burning. This cycle affects the synthesis of the elements between ^{20}Ne and ^{27}Al in asymptotic giant branch stars and novae. The ^{22}Ne(p,γ)^{23}Na reaction rate is very uncertain because of a large number of unobserved resonances lying in the Gamow window. At proton energies below 400 keV, only upper limits exist in the literature for the resonance strengths. Previous reaction rate evaluations differ by large factors. In the present work, the first direct observations of the ^{22}Ne(p,γ)^{23}Na resonances at 156.2, 189.5, and 259.7 keV are reported. Their resonance strengths are derived with 2%-7% uncertainty. In addition, upper limits for three other resonances are greatly reduced. Data are taken using a windowless ^{22}Ne gas target and high-purity germanium detectors at the Laboratory for Underground Nuclear Astrophysics in the Gran Sasso laboratory of the National Institute for Nuclear Physics, Italy, taking advantage of the ultralow background observed deep underground. The new reaction rate is a factor of 20 higher than the recent evaluation at a temperature of 0.1 GK, relevant to nucleosynthesis in asymptotic giant branch stars.

First direct measurement of the 2H(α,γ)6Li cross section at big bang energies and the primordial lithium problem.

Recent observations of (6)Li in metal poor stars suggest a large production of this isotope during big bang nucleosynthesis (BBN). In standard BBN calculations, the (2)H(α,γ)(6)Li reaction dominates (6)Li production. This reaction has never been measured inside the BBN energy region because its cross section drops exponentially at low energy and because the electric dipole transition is strongly suppressed for the isoscalar particles (2)H and α at energies below the Coulomb barrier. Indirect measurements using the Coulomb dissociation of (6)Li only give upper limits owing to the dominance of nuclear breakup processes. Here, we report on the results of the first measurement of the (2)H(α,γ)(6)Li cross section at big bang energies. The experiment was performed deep underground at the LUNA 400 kV accelerator in Gran Sasso, Italy. The primordial (6)Li/(7)Li isotopic abundance ratio has been determined to be (1.5 ± 0.3) × 10(-5), from our experimental data and standard BBN theory. The much higher (6)Li/(7)Li values reported for halo stars will likely require a nonstandard physics explanation, as discussed in the literature.

First direct measurement of the 17O(p,γ)18F reaction cross section at Gamow energies for classical novae.

Classical novae are important contributors to the abundances of key isotopes, such as the radioactive (18)F, whose observation by satellite missions could provide constraints on nucleosynthesis models in novae. The (17)O(p,γ)(18)F reaction plays a critical role in the synthesis of both oxygen and fluorine isotopes, but its reaction rate is not well determined because of the lack of experimental data at energies relevant to novae explosions. In this study, the reaction cross section has been measured directly for the first time in a wide energy range E(c.m.)~/= 200-370 keV appropriate to hydrogen burning in classical novae. In addition, the E(c.m.)=183 keV resonance strength, ωγ=1.67±0.12 µeV, has been measured with the highest precision to date. The uncertainty on the (17)O(p,γ)(18)F reaction rate has been reduced by a factor of 4, thus leading to firmer constraints on accurate models of novae nucleosynthesis.

The gluteal fold fascio-cutaneous flap for reconstruction after radical excision of primary vulvar cancers.

OBJECTIVES: Reconstructive surgery plays an important role in cosmetic and functional results of major excisional surgery performed as a treatment for invasive vulvar cancer. Traditional techniques -- gracilis myocutaneous o rectus abdominis flaps -- have several limits. We describe here a different surgical approach that we have used since 1998 in an effort to obtain better results in vulvar reconstruction. METHODS: From January 1998 to June 2007, thirty three patients who underwent excisional radical surgery for invasive vulvar tumors, were treated with vulvar reconstruction using the gluteal fold fascio-cutaneous local flap. Flaps were designed along the gluteal fold in adequate length and size. They were oval or triangular in shape depending on the defect they were supposed to cover. The flaps -- which always included the fascial layer -- were raised up to identify a perforator branch of the internal pudendal artery and then harvested as an island flap to achieve better mobility. RESULTS: We had no major complications, only two patients presented marginal necrosis and eight patients experienced significant seromas. Advantages over the alternative techniques included reduced dimensions of scars, absence of flap liponecrosis, no need of modifying patient's position on the surgical table, and very limited blood loss. CONCLUSIONS: We conclude that gluteal fold flap offers excellent cosmetic and functional results with a low complication rate. Therefore we support the gluteal fold flap as a valid surgical option whenever reconstruction is needed after radical excision of vulvar neoplasms.

Activation measurement of the 3He(alpha,gamma)7Be cross section at low energy.

The nuclear physics input from the 3He(alpha,gamma)7Be cross section is a major uncertainty in the fluxes of 7Be and 8B neutrinos from the Sun predicted by solar models and in the 7Li abundance obtained in big-bang nucleosynthesis calculations. The present work reports on a new precision experiment using the activation technique at energies directly relevant to big-bang nucleosynthesis. Previously such low energies had been reached experimentally only by the prompt-gamma technique and with inferior precision. Using a windowless gas target, high beam intensity, and low background gamma-counting facilities, the 3He(alpha,gamma)7Be cross section has been determined at 127, 148, and 169 keV center-of-mass energy with a total uncertainty of 4%. The sources of systematic uncertainty are discussed in detail. The present data can be used in big-bang nucleosynthesis calculations and to constrain the extrapolation of the 3He(alpha,gamma)7Be astrophysical S factor to solar energies.

[The STF Project: Female Tumor Screening]. / Il progetto STF--Screening Tumori Femminili.

A pilot study has been carried out to evaluate women's compliance to a screening program for cervical cancer. The study, initiated in 1994, was performed in conjunction with the ACRO project of the CNR by the Italian National Health Institute, in collaboration with La Sapienza University of Rome and the National Institute for Cancer Research in Genoa. A preliminary telephone survey was carried out on a sample of 400 women (200 in Rome and 200 in Genoa) to assess, among other factors, their attitude towards the screening program. Afterwards, an ad hoc advertising campaign was launched and 21,827 women, randomly chosen from the register office's lists, were sent a personal invitation to participate in the screening. Most women showed interest in attending the screening program at the interview, but the percentages of participation were low (25.7% in Genoa and 27.3% in Rome). On the other hand, a high percentage of women who participated in the screening had already had a Pap test in the previous three years (Genoa, 73%; Rome, 76%). The recruiting techniques that were used in this study, and that are commonly used, do not seem to reach the core of the target population for cervical screening, i.e. women who have never had a Pap test or who had a Pap test more than 5 years earlier. New methods of recruiting aimed at categories at risk and based more on direct contacts need to be developed.

Limited value of sonohysterography for endometrial screening in asymptomatic, postmenopausal patients treated with tamoxifen.

OBJECTIVES: Sonohysterography (SHG) has been proposed as a useful tool for the surveillance of the endometrium in patients receiving tamoxifen. This study aimed to assess the value of SHG in asymptomatic patients who would have been biopsy candidates because of abnormal transvaginal ultrasound (TVUS) results. METHODS: The study population included postmenopausal breast cancer patients receiving adjuvant tamoxifen who had asymptomatic abnormalities at TVUS (endometrial thickness >/=8 mm or endometrial echo not adequately visualized). SHG was performed with an Aloka SSD 680 system using a 5-MHz vaginal probe, with sterile saline solution as contrast medium. RESULTS: Forty-one patients entered the study. A regular endometrial echo was identified by SHG in 9 patients (21.9%). Histology was obtained in the remaining 32 patients with positive (n = 27, 65.8%) or unsuccessful (n = 5, 12.2%) SHG. Benign polyps (n = 15, 36.6%) and endometrial atrophy (n = 14, 34.1%) were the most common findings; 3 patients (7.3%) had simple hyperplasia. CONCLUSIONS: Breast cancer patients with asymptomatic, tamoxifen-associated TVUS abnormalities have little additional benefit from SHG. More than 23 remain candidates for biopsy, which usually yields benign or insignificant findings.

Tamoxifen and the endometrium: findings of pelvic ultrasound examination and endometrial biopsy in asymptomatic breast cancer patients.

The need for endometrial surveillance in breast cancer patients undergoing adjuvant treatment with tamoxifen is still controversial. In this study, 164 asymptomatic breast cancer patients (110 on treatment with tamoxifen, 20 mg/day, and 54 controls) were examined with pelvic ultrasound and endometrial biopsy. No differences in ultrasound and biopsy findings were observed in the pre- and perimenopausal group between patients treated with tamoxifen and controls. Postmenopausal patients on tamoxifen had a significantly thicker endometrium (mean+/-SD, 7.2+/-8.5 vs. 1.5+/-4.3 mm, p=0.00002) and significantly larger uterine volume (mean+/-SD, 63.2+/-39.9 vs. 43.7+/-38.8 cm3, p=0.0001) than controls. Fifty-four percent of patients on tamoxifen had an endometrial thickness > or = 5 mm, often with multiple irregular sonolucencies suggesting the presence of cysts. Ultrasound findings, however, did not correlate with the presence of endometrial abnormalities on biopsy, and no endometrial cancer or atypical hyperplasia were found. This lack of correlation makes questionable the use of routine sonography in asymptomatic breast cancer patients on tamoxifen. Obtaining routine endometrial samples, on the other hand, may be difficult in some patients because of cervical stenosis or refusal. Until the benefits of endometrial surveillance will be proved, asymptomatic patients should not be submitted routinely to ultrasound examination or biopsy, but encouraged to report promptly any abnormal vaginal bleeding.

[Smoking in a sample of nursing students in Genoa. Reflections on the role of professional educators]. / Abitudine al fumo di un campione di allievi infermieri genovesi. Riflessioni sul ruolo educativo della professione.

Of all European Union member states, Italy has one of the highest rates of smokers among health care personnel. One important step towards the development of a "prevention-oriented culture" is the raising of the awareness of professional working in health care structures in order to involve them in preventive actions, this making these more effective. Before undertaking measures of this kind, it is imperative to first assess the extent of the smoking habit, even at the local level, so as to target actions as precisely as possible. We herein present the results of a study carried out in two professional nursing schools of the Province of Genoa (I). In all, 341 subjects, aged between 18 and 34, were interviewed. Findings show a high percentage of smokers among both sexes, with 50.0% of males and 40.0% of females claiming to be smokers. These figures are well above national averages (32% of males and 26% of females in the national population). The age at which most interviewees began smoking ranged from 15 to 18 years; however, a rather high percentage of respondents (25.1% for males and 26.1% for females) began after 18 years of age. Our results confirm the importance of school age oriented health education programs, but highlight as well the usefulness of similar awareness initiatives for future professionals. The Italian League for the Fight Against Cancer and the Italian Association of Cancer Nurses propose to vocational training schools a collaborative effort aiming to promote healthy lifestyles among nursing students and to re-assess the role of trainers.