A Gillespie algorithm for efficient simulation of quantum jump trajectories

The jump unravelling of a quantum master equation decomposes the dynamics of an open quantum system into abrupt jumps, interspersed by periods of coherent dynamics where no jumps occur. Simulating these jump trajectories is computationally expensive, as it requires very small time steps to ensure convergence. This computational challenge is aggravated in regimes where the coherent, Hamiltonian dynamics are fast compared to the dissipative dynamics responsible for the jumps. Here, we present a quantum version of the Gillespie algorithm that bypasses this issue by directly constructing the waiting time distribution for the next jump to occur. In effect, this avoids the need for timestep discretisation altogether, instead evolving the system continuously from one jump to the next. We describe the algorithm in detail and discuss relevant limiting cases. To illustrate it we include four example applications of increasing physical complexity. These additionally serve to compare the performance of the algorithm to alternative approaches -- namely, the widely-used routines contained in the powerful Python library QuTip. We find significant gains in efficiency for our algorithm and discuss in which regimes these are most pronounced. Publicly available implementations of our code are provided in Julia and Mathematica.Comment: 13 pages, 4 figures. Comments welcom

Empirical insights on the nature of synergies among HRM policies - an analysis of an ethics-oriented HRM system

In the last years, several HRM scholars have theoretically support the idea that the policies bundled in an HRM system present synergistic effects. Surprisingly, empirical studies about those synergistic effects are scarce, and their results unstable. As a result, some critical voices in the HR field are questioning the idea of synergies among HR policies, and calling for more research which does not take them for granted. Addressing this gap, this study tests the existence and nature of synergies in HRM systems targeted at improving the employees' perception of benevolent and principled ethical climates. Results from a probabilistic sample of 6000 employees from 6 European countries highlight that synergies occur both for benevolent and principled ethical climates, even if the specific components of the HRM system presenting synergistic effects are different in the two cases. Implications of the findings for HRM practice are presented and discussed

How are professionals recruited by external agents in misconduct projects? The infiltration of organized crime in a university

Private firms, crime organizations or states may successfully recruit professionals in misconduct projects. How they do so remains however under investigated. Past studies mostly take professionals’ perspective, or limit the organizational initiative of external agents to perverse incentives and threats. Our study shows instead how external agents may penetrate governance bodies and professional events to recruit and control professionals, who are both aware of and reluctant toward misconduct. Our longitudinal case study used judicial and non-judicial sources to analyse how a mafia clan infiltrated Troy University, and controlled the trade of exams and admissions for decades. The clan selected Troy University because of the presence of professors predisposed toward misconduct. The clan infiltrated the predisposed professors inside governance bodies and students inside academic events to recruit the reluctant professors with peer pressures, situated threats and administrative controls. It then exploited a generalized code of silence to control professionals for years. Overall, the study highlights the combination of perverse and pervasive mechanisms to recruit professionals; the role of corrupt professionals as lynchpin between external agents and reluctant peers; and the perverse exploitation of normal professional practices of autonomy, trusteeship and multiple embeddedness

Stochastic metrology and the empirical distribution

We study the problem of parameter estimation in time series stemming from general stochastic processes, where the outcomes may exhibit arbitrary temporal correlations. In particular, we address the question of how much Fisher information is lost if the stochastic process is compressed into a single histogram, known as the empirical distribution. As we show, the answer is non-trivial due to the correlations between outcomes. We derive practical formulas for the resulting Fisher information for various scenarios, from generic stationary processes to discrete-time Markov chains to continuous-time classical master equations. The results are illustrated with several examples.Comment: 16 pages, 8 figures, 1 tabl

Rearing temperature effect on the skeletal muscle fibres of Acipenser baerii yolk-sac larvae

Siberian sturgeon farming is important because it provides an alternative source of caviar and meat, but also for the conservation of the endangered natural stocks. Farmed fish is continuously subjected to stress factors, of which, water temperature is considered a major one (Schram et al., 2006). It has been demonstrated that physiological stress may have serious negative consequences on growth (Wendelaar Bonga, 1997) and that fish larvae appear less tolerant than adults to temperature variations (Stefanovich et al., 2016). The present study aims at investigating the stress response and development in precocious stages of siberian sturgeon when subjected to different rearing temperatures, by analysing ontogeny, growth and stress response of yolk-sac larvae. This study was approved by the Ethic Committee of the University of Milan (OPBA_20_2016). Fertilized Siberian sturgeon eggs were reared at 16°C, 19°C and 22°C until complete yolk-sac absorption. Sampling timepoints were: hatching, schooling and complete yolk-sac absorption stage. Water parameters and larvae development data were registered. Histological, histochemical and immunohistochemical analyses were performed in order to assess ontogeny and stress biomarkers and whole body cortisol was measured by a specific microtitre radioimmunoassay (RIA). Statistical analysis was performed with SAS software (v. 9.3, Cary Inc., NC). Larvae subjected to the highest water temperature showed a faster yolk-sac absorption and larvae body weight significantly increased from hatching onwards. Structural normal development considering the three different temperatures investigated from hatching until the end of the trial was observed. Significant differences were found between temperatures regarding body weight and cortisol levels (P<0.01). A qualitative stronger expression of stress markers was noticed in larvae subjected to the lower temperature. Even if this study indicates that lower rearing temperatures would appear more suitable for Siberian sturgeon rearing, further studies would be necessary to evaluate the temperature effect on a mid-long term basis

Effect of genotype, gender and feed restriction on growth, meat quality and the occurrence of white striping and wooden breast in broiler chickens

Due to their importance for the control of meat quality in broiler chickens, the present study aimed at identifying the factors associated with the occurrence of myopathies and characterizing the meat properties when affected by myopathies. To this aim, a total of 768 broiler chickens were reared until slaughter (46 d) to evaluate the effect of genotype, gender, and feeding regime (ad libitum vs. restricted rate, 80% from 13 to 21 d of age) on performance and meat quality. Standard broilers were heavier (3,270 vs. 3,139 g; P < 0.001) and showed lower feed conversion (1.56 vs. 1.61; P < 0.001) than the high-yield broilers. Males showed higher final live weight (3,492 vs. 2,845 g) and lower feed conversion (1.54 vs. 1.63) than females (P < 0.001). Feed restriction decreased final live weight (3,194 vs. 3,142 g; P < 0.01) and feed conversion (1.60 vs. 1.57; P < 0.01) compared to ad libitum feeding. At gross examination, feed restriction tended to increase white-striped breasts (69.5 vs. 79.5%; P < 0.10), whereas females showed less wooden breasts than males (8.0 vs. 16.3%; P < 0.05). White-striped fillets had higher pHu (5.87 vs. 5.83), and lower a 17 ( 120.81 vs. 120.59) and b 17 color indexes (13.7 vs. 14.5) (P < 0.05), whereas wooden breast fillets exhibited higher cooking losses (25.6 vs. 22.1%) and AK-shear force (4.23 vs. 2.84 kg/g) compared with normal fillets (P < 0.001). At histological examination, 3.1% of pectoralis major were normal, 26.6% mildly degenerated, 45.3% moderately degenerated, and 25.0% severely degenerated. In conclusion, genotype had a moderate effect on growth without modifying myopathy occurrence. In contrast, gender and feed restriction affected performance, meat quality, and breast abnormalities

No Untoward Effect of Long-Term Ketoconazole Administration on Electrocardiographic QT Interval in Patients with Cushing's Disease.

Ketoconazole is listed among drugs that prolong QT interval and may increase the risk of torsade de pointes, a severe ventricular arrhythmia. This compound has recently been approved for treatment of Cushing's syndrome, a severe endocrine disorder. These patients harbour several risk factors for prolonged QT interval, for example hypokalaemia and left ventricular hypertrophy, but no study has evaluated whether administration of ketoconazole affects their QT interval. The aim of this study was to assess the QT interval in patients with Cushing's disease during long-term administration of ketoconazole. Electrocardiograms from 15 patients with Cushing's disease (12 women, 3 men, age: 37.8 ± 2.66 years) on ketoconazole treatment (100 mg-800 mg qd) for 1 month to 12 years were reviewed retrospectively. QT interval was measured and corrected for heart rate (QTc). Measurements before and during ketoconazole treatment were compared and any abnormal QTc value recorded. Concurrent medical therapies were also documented. On average, QTc was superimposable before and during ketoconazole treatment (393.2 ± 7.17 versus 403.3 ± 6.05 msec. in women; 424.3 ± 23.54 versus 398.0 ± 14.93 msec. in men, N.S.). QTc normalized on ketoconazole in one man with prolonged QTc prior to treatment; no abnormal QTc was observed in any other patient during the entire observation period, even during concurrent treatment with other QT-prolonging drugs. In conclusion, long-term ketoconazole administration does not appear to be associated with significant prolongation of QT interval in patients with Cushing's disease. ECG monitoring can follow recommendations drawn for other low-risk QT-prolonging drugs with attention to specific risk factors, for example hypokalaemia and drug interactions

Organized crime and employment relations : a personal story of ‘Ndrangheta control on employment relations management practices in Southern Italy

This article sets out the testimony of Paolo, an Italian entrepreneur who worked under the control of an ‘Ndrangheta clan for years, and finally rebelled against that criminal organization. Paolo operated on a crucial front line, as he managed the relations between his company and the dominant criminal organization in his area. This story constitutes a ‘wake-up call’ for more research on the intrusion of organized crime in the labour market. Paolo’s story reveals how strongly organized crime can penetrate decision-making processes and control key people’s management practices. Such control is decisive not only while under the direct influence of organized crime, but also after rebelling against it. Overall, this article provides insights into how organized crime affects employment relations and it calls for more attention to be paid to this topic in the sociology of work and employment relations

Differently unequal: Zooming-in on the distributional dimensions of the crisis in euro area countries

This paper discusses how income inequality developed during the current crisis in euro area countries, as well as the role played by each income source. Based on an extended definition of income - including additional components which do not appear in the standard Eurostat definitions - we complement the information provided by the Gini index and quantile ratios by computing an alternative inequality indicator, developed by Zenga (2007), and its decomposition by income source. While broadly confirming the distributional effect of the crisis documented in previous studies, we find that in specific countries the level of inequality appears higher when alternative measures are taken into account, and that the rise of inequality since 2008 has not been as modest as the previous studies would suggest. The paper further looks at how the distribution of income has evolved during the crisis by income quantile groups (i.e. 'zooming-in'). The results point to varying contribution of labour income in 2011 compared to 2007. In addition, while the impact of individual households' characteristics shows a non-linear pattern across income quantile groups before the crisis, such dispersion has decreased in 2011.We argue that, on the basis of our analysis, not only euro area countries are "differently unequal" in that inequality has developed in a very peculiar way in different countries, but also because it needs to be tackled at a finer level of analysis

Mosquito-Borne Diseases and ‘One Health’: The Northwestern Italian Experience

In Italy, the surveillance of Mosquito-Borne Diseases (MBDs) is regulated by two national preparedness plans: (1) for West Nile and Usutu viruses, integrating human and veterinary surveillance in order to early detect viruses circulation and to quickly apply control measures aimed at reducing the risk of transmission through blood and blood components and (2) for Arbovirosis transmitted by Aedes mosquitoes, mainly Chikungunya, Dengue and Zika viruses, based on surveillance of both imported and autochthonous human cases. This chapter reports the results of the application of these National Plans in Northwestern Italy and their impact for human health. In detail, we present the coordinated activities enforced in Piemonte and Liguria Regions, as a good example of the ‘One Health approach’ to control MBDs and prevent human transmission