Time properties of the the rho-class burst of the microquasar GRS 1915+105 observed with BeppoSAX in April 1999

We present a temporal analysis of a BeppoSAX observation of GRS 1915+105 performed on April 13, 1999 when the source was in the rho class, which is characterised by quasi-regular bursting activity. The aim of the present work is to confirm and extend the validity of the results obtained with a BeppoSAX observation performed on October 2000 on the recurrence time of the burst and on the hard X-ray delay. We divided the entire data set into several series, each corresponding to a satellite orbit, and performed the Fourier and wavelet analysis and the limit cycle mapping technique using the count rate and the average energy as independent variables. We found that the count rates correlate with the recurrence time of bursts and with hard X-ray delay, confirming the results previously obtained. In this observation, however, the recurrence times are distributed along two parallel branches with a constant difference of 5.2+/-0.5 s.Comment: Accepted for publication in Section 7. Stellar structure and evolution of Astronomy and Astrophysic

Lyapunov functions for a non-linear model of the X-ray bursting of the microquasar GRS 1915+105

This paper introduces a biparametric family of Lyapunov functions for a non-linear mathematical model based on the FitzHugh-Nagumo equations able to reproduce some main features of the X-ray bursting behaviour exhibited by the microquasar GRS 1915+105. These functions are useful to investigate the properties of equilibrium points and allow us to demonstrate a theorem on the global stability. The transition between bursting and stable behaviour is also analyzed.Comment: Published on International Journal of Non-Linear Mechanics, vol. 88, pp. 142-14

Role of systemic inflammation scores in pulmonary metastasectomy for colorectal cancer

Background: Patients with pulmonary metastases from colorectal cancer can benefit from surgical removal.However, the biological determinants of postsurgical outcome are not completely elucidated. We evaluated the role of host systemic inflammation status in this setting. Methods: The modified Glasgow prognostic score (based on serum C-reactive protein and albumin levels) and the neutrophil-to-lymphocyte (NTL) ratio were obtained from 44 patients who received curative-intent metastasectomy, and were used as indicators of systemic inflammation status.We tested the impact of both of these parameters on overall survival (OS) and progression-free survival (PFS), as well as their correlation with other well-known prognosticators. Results: Five-year PFS and OS rates were 18% and 49%, respectively. At univariate analysis,multiple metastases, disease-free interval <36 months, and a Glasgow score of 2 (P = 0.031)were significantly associated to aworse PFS rate.A NTL ratio >3 predicted disease progression in the short-term(P = 0.036), but the effect on late events was weaker (P = 0.079). Factors associated with worse OS were multiple metastasis (P = 0.002), elevated carcinoembryonic antigen (P = 0.009), a Glasgowscore of 2 (P = 0.029), and a faster metastasis growth (P = 0.008).At Cox regression analysis, neither a Glasgow score of 2, nor elevated NTL ratio showed an independent effect on survival rates. Conclusions: Systemic inflammation scores did not perform well as independent survival prognosticators in patients undergoing curative-intent pulmonary metastasectomy. Further investigation is warranted to evaluate whether these measurements could still be useful when restricting the analysis to specific patient subcategories or to diverse postoperative phases

Excitation transport with collective radiative decay

We investigate a one-dimensional quantum emitter chain where transport of excitations and correlations takes place via nearest neighbor, dipole-dipole interactions. In the presence of collective radiative emission, we show that a phase imprinting wavepacket initialization procedure can lead to subradiant transport and can preserve quantum correlations. In the context of cavity mediated transport, where emitters are coupled to a common delocalized optical mode, we analyze the effect of frequency disorder and nonidentical photon-emitter couplings on excitation transport

Duration of air leak is reduced after awake nonresectional lung volume reduction surgery

OBJECTIVE: Prolonged air leak occurs frequently after lung volume reduction surgery (LVRS) and can negatively affect both morbidity and hospital stay. We hypothesised that awake nonresectional LVRS could reduce the duration of air leak in emphysema patients. METHODS: This analysis included 66 patients undergoing awake, unilateral plication of the most emphysematous lung regions under sole epidural anaesthesia. Primary outcome measure was the rate of prolonged (>7 days) air leak; secondary outcome measures included the mean duration of air leak, hospital stay and early discharges (<or=4 days). All results were retrospectively compared with those of a similar control group undergoing resectional LVRS under general anaesthesia. RESULTS: Intergroup comparisons showed that demographics and baseline data were well matched. Prolonged air leak occurred in 12 patients (18%) in the awake group versus 27 patients (40%) in the control group (p=0.007) with a mean duration of 5.2+/-6.5 days versus 7.9+/-7.6 days (p<0.0002). Mean hospital stay was significantly shorter in the awake group (6.3+/-2.8 days vs 9.2+/-5.6 days, p<0.0001). At univariate analysis, resectional LVRS (p=0.007), higher severity of emphysema (p<0.0001) and lower diffusion capacity for carbon monoxide (p=0.0001) correlated with occurrence of prolonged air leak; however, logistic regression indicated high severity of emphysema as the most important factor predicting prolonged air leak (odds ratio=4.85, p<0.0001). At 6 months, dyspnoea index, FEV1 and 6 min walking test improved significantly in both study groups. CONCLUSIONS: In this study, awake nonresectional LVRS was associated with a lower rate of prolonged air leak and a shorter hospital stay than the standard resectional technique

The complex time behaviour of the microquasar GRS 1915+105 in the \rho-class observed with BeppoSAX. III: The hard X-ray delay and limit cycle mapping

The microquasar GRS1915+105 was observed by BeppoSAX in October 2000 for about ten days while the source was in \rho-mode, which is characterized by a quasi-regular type I bursting activity. This paper presents a systematic analysis of the delay of the hard and soft X-ray emission at the burst peaks. The lag, also apparent from the comparison of the [1.7-3.4] keV light curves with those in the [6.8-10.2] keV range, is evaluated and studied as a function of time, spectral parameters, and flux. We apply the limit cycle mapping technique, using as independent variables the count rate and the mean photon rate. The results using this technique were also cross-checked using a more standard approach with the cross-correlation methods. Data are organized in runs, each relative to a continuous observation interval. The detected hard-soft delay changes in the course of the pointing from about 3 s to about 10 s and presents a clear correlation with the baseline count rate.Comment: accepted for publication in A&

Company Competitiveness as a Variable Success Strategy for the Territory and the Environment

Supporting the fortunes of the Made in Italy agri-food brand are the best quality products which can be found throughout the Italian territory and which, in many cases, derive from Southern Italy, with a particularly interesting role assumed by Campania and Sicily.The Sicily Region boasts a varied and peculiar food and wine heritage, especially from a qualitative point of view, the Born in Sicily brand, made with excellent raw materials which constitute and support the development of important production lines within the agro-industrial sector.Among the most important food industries in Italy and on the island, there are some operating in the confectionery industry. Today the fast-growing confectionery industry contributes a great deal to the agri-food system.This study analyzes the agri-food system both in Italy and Sicily, highlighting the main sectors which contribute to make the Made in Italy brand competitive around the world and how companies have succeeded in starting up some interesting internationalization processes.This the reason why a specific case regarding a Sicilian confectionery industry is examined so as to understand how it was able to create such a successful innovative product, establishing itself on both the national and international market.The results show that entrepreneurial skills contribute a great deal to creating business competitiveness and territorial development