A preliminary examination of differential decomposition patterns in mass graves

This study represents a preliminary, quantitative approach to the examination of differential decomposition patterns in mass graves. Five pairs of mass graves, each containing the carcasses of 21 rabbits, were used to examine decomposition rates at four fixed positions within the burial. A pair of graves was exhumed at approximately 100 accumulated degree day (ADD) intervals. At exhumation the total body score (TBS) and internal carcass temperature of each rabbit were recorded. Although there was no significant difference between decomposition rates for core and deep-positioned carcasses (p = 0.13), all other position differences were significant (p < 0.001). Decomposition occurred fastest in shallow carcasses, followed by mid-outer carcasses; both deep and core carcasses exhibited a slower rate. Internal carcass temperature was significantly influenced by carcass location within the mass grave; there was a mean internal temperature difference of ca. 1 oC between deep and shallow carcasses (30 cm apart). Adipocere formation was minimal and confined, with the exception of a single individual in the mid- periphery, to the deepest level. Decomposition rate may be as affected by the compactness of a mass as by interment depth and/or peripheral substrate contact, and further investigation into the role of oxygenation and pH are required

Interval identification of natural effects in the presence of outcome-related unmeasured confounding

With reference to a binary outcome and a binary mediator, we derive identification bounds for natural effects under a reduced set of assumptions. Specifically, no assumptions about confounding are made that involve the outcome; we only assume no unobserved exposure-mediator confounding as well as a condition termed partially constant cross-world dependence (PC-CWD), which poses fewer constraints on the counterfactual probabilities than the usual cross-world independence assumption. The proposed strategy can be used also to achieve interval identification of the total effect, which is no longer point identified under the considered set of assumptions. Our derivations are based on postulating a logistic regression model for the mediator as well as for the outcome. However, in both cases the functional form governing the dependence on the explanatory variables is allowed to be arbitrary, thereby resulting in a semi-parametric approach. To account for sampling variability, we provide delta-method approximations of standard errors in order to build uncertainty intervals from identification bounds. The proposed method is applied to a dataset gathered from a Spanish prospective cohort study. The aim is to evaluate whether the effect of smoking on lung cancer risk is mediated by the onset of pulmonary emphysema.Comment: 14 pages, 2 figures, 2 table

Modelli di scoring per il rischio paese

Country risk and sovereign risk are two of the most important topics in risk management. The first part of this work introduces these concepts and shows the differences between them. The following chapters fit linear and ordinal regression models to a data-set with more than 100 countries, where the response variable is an appropriate measure of their creditworthiness. The main purposes are to identify the most relevant explanatory variables and to make predictions for those countries whose response variable is not available. For the second aim it is important to verify that records with missing values are not systematically different from the complete ones: a Little test for the MCAR hypothesis is implemented. About model selection, ad hoc algorithms are used and the theory of reduction, proposed by David Hendry, is also briefly described

Valutazione dell'influenza di parametri clinico-strumentali sui livelli di mesotelina sierica in una popolazione di lavoratori ex esposti ad amianto

L’esposizione lavorativa all’amianto può provocare varie patologie respiratorie come l'asbestosi, il versamento pleurico, le placche pleuriche, fino a patologie tumorali come il tumore del polmone ed il mesotelioma pleurico maligno, patologia per la quale ad oggi non esistono trattamenti radicali in grado di incidere sulla mortalità. Diversi sono i protocolli medici di sorveglianza sanitaria dei lavoratori ex esposti ad amianto ad oggi proposti. Su una coorte di più di 600 ex esposti seguiti presso l'ambulatorio di Medicina del Lavoro dell'Azienda Ospedaliero Universitaria Pisana, è stato adottato un protocollo che oltre alla visita medica con particolare attenzione all'anamnesi lavorativa, ad alcuni accertamenti radiologici (Rx ed eventuale TAC torace) e alle prove di funzionalità respiratoria ha visto anche l'innovativa introduzione di alcuni markers biologici, tra i quali la mesotelina sierica. Questo marker, ancora in fase di studio, è da molti suggerito come un utile strumento nella individuazione di sub-popolazioni a maggior rischio di patologie neoplastiche amianto correlate. Non del tutto conosciute sono le funzioni ed interazioni fisiologiche e fisiopatologiche di questa molecola. Conseguentemente, con la presente tesi si è voluto valutare la possibile influenza di alcuni parametri clinico strumentali sui livelli di mesotelina sierica, che potrebbero infine agire come fattori di confondimento inficiando così l’utilizzo concreto della mesotelina

Modelli di scoring per il rischio paese

Country risk and sovereign risk are two of the most important topics in risk management. The first part of this work introduces these concepts and shows the differences between them. The following chapters fit linear and ordinal regression models to a data-set with more than 100 countries, where the response variable is an appropriate measure of their creditworthiness. The main purposes are to identify the most relevant explanatory variables and to make predictions for those countries whose response variable is not available. For the second aim it is important to verify that records with missing values are not systematically different from the complete ones: a Little test for the MCAR hypothesis is implemented. About model selection, ad hoc algorithms are used and the theory of reduction, proposed by David Hendry, is also briefly described

3D CFD Simulation of a New Ventilated Roof

In the last decades, energy management and saving have become challenging issues. Considering the building sector (residential or industrial), different technologies have been developed in order to realize tangible energy savings, such as: ventilated roof, double facades, glazed surfaces, etc. Nonetheless, it is important for these new technologies to contemporary assure the human thermal comfort. Passive cooling (or heating) technologies are of actual interest. Low or near-zero energy buildings can only be realized as a result of the good design of all their components; specifically, the roofs call for particular attention as they take large parts of a building’s total surface area. This paper presents a comparison between an innovative ventilated roof, based on an original design of the support and a traditional one. A 3D numerical model is developed to analyze the air flow and to compute the achievable benefits in terms of reduction of the summer heating gains. The simulations were performed by varying the solar irradiance from 600 to 1000 W m2. The investigation is conducted comparing a ventilated roof assembly to the same traditional structure, assuming buoyancy-driven airflow. Two roof types are studied: an insulated roof and a non-insulated one. The results reveal that the ventilated roof leads to a great reduction of the total amount of solar heat gains for all the simulated scenarios