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In electron beam welding a very intense pencil beam of electrons is driven onto the base metal, to melt it and produce the welding. In the interaction of the beam with the metal, strong bremsstrahlung emission of X-ray is generated. Here the generation is evaluated, and the KERMA in air at 1 m is predicted. Results show that a significant radiation hazard is present and serious radiation protection measures are needed.

Klinefelter syndrome is a frequent cause of hypogonadism, but despite hundreds of publications on different aspects of Klinefelter syndrome, only a few studies dealt with sexual dysfunction. In particular, testosterone is critical for various aspects of sexual response, but its role on sexuality in Klinefelter syndrome patients is debatable and no studies have evaluated the efficacy of testosterone treatment on sexual dysfunction in these subjects. Furthermore, the impact of psychological and relational aspects on sexual function of Klinefelter syndrome subjects is poorly defined. In this study, we aimed to determine the presence and type of sexual dysfunctions in Klinefelter syndrome subjects; to correlate them with testosterone levels and psychosexological and relational domains; and to evaluate the effects of testosterone therapy. We studied 62 non-mosaic naïve Klinefelter syndrome patients and 60 age-matched controls by means of medical history, psychosexological history, 15-item International Index of Erectile Function questionnaire, endocrine assessment, and dynamic penile color Doppler ultrasound. Twenty-five hypogonadal Klinefelter syndrome patients were studied after 6 months of testosterone replacement therapy. Klinefelter syndrome subjects have reduced 15-item International Index of Erectile Function scores regarding sexual desire, intercourse satisfaction, and overall satisfaction with respect to controls, and these aspects were significantly associated with testosterone levels. Klinefelter syndrome subjects had also higher prevalence of erectile dysfunction, but no relation with testosterone levels was evident. A high prevalence of a range of psychological disturbances was present in Klinefelter syndrome subjects with erectile dysfunction with respect to those without erectile dysfunction. No statistical difference in the prevalence of premature and delayed ejaculation was observed between Klinefelter syndrome and control subjects. Testosterone replacement therapy improved sexual desire, intercourse satisfaction, and overall satisfaction scores, but had no effect on erectile function. Penile color Doppler ultrasound was normal in all subjects. This study shows that sexual dysfunction in Klinefelter syndrome is multifactorial and related only in part to hypogonadism and largely to psychological disturbances. Evaluation and therapy of sexual dysfunction should include a combined andrological and psychosexological approach.

Background The value of adding carboplatin (Cb) to neoadjuvant chemotherapy for TNBC is debated. Current evidence supports the association between Cb use and increased pathological complete response (pCR) rate. However, treatment schedules and doses adopted in randomized trials were not always consistent with those used in clinical practice. Methods Clinicopathological data of TNBC (ER & PgR Results 166 patients were included: 61% treated with AT, 39% with AT+Cb (all patients in this group received Cb AUC2 weekly administered concomitantly to the taxane segment). Main characteristics: median age 50 yrs, ductal histology 93%, grade 3 90%, cT > 2cm 86%, cN + 57%, median TILs 10%, median Ki67 60%, BRCA mutated 10%. After propensity score matching, pCR rate was significantly higher for AT+Cb vs AT: 52% vs 31% (OR 2.39 95%CI 1.04-5.50, p = 0.040). In multivariable analysis, treatment with AT+Cb maintained an independent association with pCR: OR 2.51 95%CI 1.03-6.11, P = 0.043. The achievement of pCR was significantly associated with improved disease-free survival (HR 0.16, 95%CI 0.06-0.45). No difference in DFS was observed comparing AT+Cb vs AT: HR 0.99, 95%CI 0.44-2.25. Conclusions We confirmed in a clinical practice setting the association of Cb-containing neoadjuvant chemotherapy with higher pCR rates. Additional data are needed to clarify the impact on long-term survival. These data support the conditional positive recommendation for Cb inclusion in neoadjuvant chemotherapy for TNBC provided by the Italian Association of Medical Oncology Guidelines on Breast Cancer. Funding Has not received any funding. Disclosure M.V. Dieci: Advisory / Consultancy: Eli Lilly; Advisory / Consultancy: Celgene; Advisory / Consultancy: Genomic Health. V. Guarneri: Advisory / Consultancy: Eli Lilly; Advisory / Consultancy: Novartis; Advisory / Consultancy: Roche; Speaker Bureau / Expert testimony: Eli Lilly; Speaker Bureau / Expert testimony: Novartis; Research grant / Funding (institution): Roche. All other authors have declared no conflicts of interest.

Spectral purity and source stability represent two of the primary goals in the design of high performance frequency synthesizer for modern radar systems. This paper presents a new X-band High Stable Synthesizer (HSS) architecture, which combines Phase Lock Loop (PLL), Direct Digital Synthesis (DDS) and multiplier techniques, in order to cope with low phase noise and frequency agility requirements of the next radar generations. This synthesizer offers frequency coverage in X band with a percentage bandwidth of a minimum of 10%, with fast switching time, high digitally-tunable resolution and very low phase noise. The achievement of such performance has been demonstrated by experimental results measured on a laboratory demonstrator: they show a lock-in time within 10 us and a phase noise improvement up to 30 dB compared to the current state of art Frequency Generation Unit (FGU). Moreover, for its versatility, the architecture is able to provide an intermediate output covering the needs for new S-L band application.

Recent interest in a severe accident management scheme known as ‘In-Yessel Retention’ has created the need to establish the coolability limits of large, inverted geometries. In this paper, full-scale simulations conducted at UCSB's ULPU facility are examined at the microscopic level. Because of the peculiar geometry, it has become possible to directly visualize the boiling transition phenomenon, and with the help of microthermocouples to quantitatively identify the mechanism of dryout. Altogether, a new boiling transition regime was identified, with a significant coupling between overall systems dynamics and the microphenomena. This leads the way to the a priori prediction of critical heat flux and factors that may influence it.

The conditions of the MAGICO-2000 experiment are extended to more broadly investigate the regimes of premixing, and the corresponding internal structures of mixing zones. With the help of the data and numerical simulations using the computer code PM-ALPHA, we can distinguish extremes of behavior dominated by inertia and thermal effects—we name these the inertia and thermal regimes, respectively. This is an important distinction that should guide future experiments aimed at code verification in this area. Interesting intermediate behaviors are also delineated and discussed.

Lower head integrity under steam explosion loads in an AP600-like reactor design is considered. The assessment is the second part of an evaluation of the in-vessel retention idea as a severe accident management concept, the first part (DOE:ID-10460) dealing with thermal loads. The assessment is conducted in terms of the risk oriented accident analysis methodology (ROAAM), and includes the comprehensive evaluation of all relevant severe accident scenarios, melt conditions and timing of release from the core region, fully three-dimensional mixing and explosion wave dynamics, and lower head fragility under local, dynamic loading. All of these factors are brought together in a ROAAM probabilistic framework to evaluate failure likelihood. The conclusion is that failure is 'physically unreasonable'. © 1999 Elsevier Science S.A. All rights reserved.

An overall verification approach for the PM-ALPHA code is presented and implemented. The approach consists of a stepwise testing procedure focused principally on the multifield aspects of the premixing phenomenon. Breakup is treated empirically, but it is shown that, through reasonable choices of the breakup parameters, consistent interpretations of existing integral premixing experiments can be obtained. The present capability is deemed adequate for bounding energetics evaluations.

As computations of transient, multidimensional, multiphase flows are becoming increasingly more realistic, so increases the demand for their detailed experimental validation. Key in this task is the evolution of flow patterns, and the usual approaches of local measurements are inherently limited in meeting this demand. In this paper, we demonstrate the particular suitability of flash X-ray radiography, and the feasibility of reliably quantifying the radiographs of flow regions of various sizes, from microscopic to rather large scale.

The ACOPO experiment simulates natural convection heat transfer from volumetrically heated pools, at a half-scale reactor lower head geometry (hemispherical). Data for Rayleigh numbers of up to 2·1016, from the first round of experiments, are presented in this paper. The results are in substantial agreement with those of the mini-ACOPO proof-of-concept experiment. Moreover, it is shown that these ACOPO results confirm a key component of the in-vessel retention capability for an AP600-like design, as recently established in DOE/ID-10460.

The thermal field in a reactor vessel downcomer and resulting thermal/stress response in the adjacent reactor vessel wall during high-pressure safety injection are examined, especially with regard to departures from one-dimensional behavior. Similarity solutions for the stratification (in the cold leg) that creates the downcomer plumes, and scaling considerations for the thermal conduction and stress fields in the vessel wall are developed to provide generalized criteria for the adequacy of the one-dimensional treatment.

The efficacy of external flooding of a reactor vessel as a severe accident management strategy is assessed for an AP600-like reactor design. The overall approach is based on the Risk Oriented Accident Analysis Methodology (ROAAM), and the assessment includes consideration of bounding scenarios and sensitivity studies, as well as arbitrary parametric evaluations that allow the delineation of the failure boundaries. Quantification of the input parameters is carried out for an AP600-like design, and the results of the assessment demonstrate that lower head failure is physically unreasonable. Use of this conclusion for any specific application is subject to verifying the required reliability of the depressurization and cavity-flooding systems, and to showing the appropriateness (in relation to the database presented here, or by further testing as necessary) of the thermal insulation design and of the external surface properties of the lower head, including any applicable coatings. The AP600 is particularly favorable to in-vessel retention. Some ideas to enhance the assessment basis as well as performance in this respect, for applications to larger and/or higher power density reactors are also provided.

The efficacy of external flooding of a reactor vessel as a severe accident management strategy is assessed for an AP600-like reactor design. The overall approach is based on the Risk Oriented Accident Analysis Methodology (ROAAM), and the assessment includes consideration of bounding scenarios and sensitivity studies, as well as arbitrary parametric evaluations that allow the delineation of the failure boundaries. Quantification of the input parameters is carried out for an AP600-like design, and the results of the assessment demonstrate that lower head failure is physically unreasonable. Use of this conclusion for any specific application is subject to verifying the required reliability of the depressurization and cavity-flooding systems, and to showing the appropriateness (in relation to the database presented here, or by further testing as necessary) of the thermal insulation design and of the external surface properties of the lower head, including any applicable coatings. The AP600 is particularly favorable to in-vessel retention. Some ideas to enhance the assessment basis as well as performance in this respect, for applications to larger and/or higher power density reactors are also provided.