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Pitting is one of the main causes of failure in planetary gear sets of axles designed for agricultural vehicles. The high torque and the low wheel speed typical of such machines result in poor lubrication and promote the onset of contact fatigue failure by pitting, which generally occurs earlier in the sun gear than in both the planets and the ring of wheel hub planetary drives. In fact, sun gears are subjected to the highest contact pressure and, at the same time, unfavourable rolling-sliding working conditions. In this paper, six case hardened sun gears damaged by pitting during endurance tests were analysed. The aim of the analysis was to highlight the key aspects of the morphology and the evolution of pitting damage on the case hardened sun gears. [ABSTRACT FROM AUTHOR]

The industry of off-highway vehicles is one of the fields of major application of nodular cast irons, which guarantee the manufacture of complex geometries and ensure good mechanical properties. The present investigation deals with the fatigue design of off-highway axles made of EN-GJS-500-7. Typically, off-highway axles are weakened by stress risers which must be assessed against fatigue. In this investigation, laboratory specimens have been extracted from an off-highway axle to take into account the manufacturing process effects. Different specimens' geometries have been prepared, including plain, bluntly notched and sharply V-notched specimens, and constant amplitude, load-controlled axial fatigue tests were conducted using two nominal load ratios, namely push-pull and pulsating tension loading. As a result, both the notch and the mean stress effects on the fatigue behaviour of EN-GJS-500-7 have been experimentally investigated for the first time. A well-known local approach, which takes the strain energy density (SED) averaged over a properly defined structural volume as a fatigue damage parameter, has been applied both in the linear elastic and elastic plastic formulations. Since the SED correlated the geometrical notch effects of the specimens as well as the mean stress effects, a master curve based on the averaged SED has been defined for the first time, to the best of the authors' knowledge, for the fatigue design of off-highway axles made of EN-GJS-500-7.

Introduction: Severe spontaneous bleeding is a significant complication in patients with continuous flow left ventricular assist devices; there is little evidence on endovascular treatment to support its use., Materials and Methods: We observed seven patients (five men, two women, age 43-67 years) with continuous flow left ventricular assist devices on antiaggregant/coagulant therapy, admitted to our hospital for uncorrectable symptomatic anemia; CT-angiography and diagnostic angiography confirmed the presence of atraumatic arterious bleeding from the gastrointestinal tract (six patients), from the intercostal artery and from the bronchial tree (one patient)., Results: All patients where successfully treated via an endovascular approach with superselective embolization of the involved arterial branches with coils and particles., Conclusion: Spontaneous atraumatic bleeding is a frequent complication in patients with continuous flow left ventricular assist devices; endovascular treatment represents a promising alternative to the surgical approach as it is less invasive, easily repeatable and associated to a reduced procedural risk.

Death due to mechanical or chemical intoxication of heroin body packers, thanks to the continuous improvement in packaging techniques, are increasingly rare, and almost all the cases reported in the literature refer to drug swallowers. A case of fatal acute heroin intoxication in a body pusher with an unreported packaging technique is presented, and previous deaths due to heroin body packing are reviewed, taking into consideration imaging techniques performed, cause of death, toxicological analysis on biological and non-biological samples, as well as number, position and type of drug packages identified at the dissection of the body. The innovative packaging technique found in the present case, constituted by an external multilayer cellophane casing containing 16 smaller packages of hardened heroin powder, each one covered with cigarette paper and multiple layers of heat-sealed cellophane, was probably used to avoid both chemical complications of package rupture and to create a package with morphological and radiological features different from those reported by previous studies. Drug dealers, in fact, are continually looking for packaging methods that, besides being safer, minimize the risk of detection at the radiological examinations performed, thus increasing the number of false negative findings. The identification of new types of package is therefore important, in order to identify packages that do not have the typical radiological signs, both in order to protect the patient's health and to avoid the non-recognition of a drug carrier. Despite the presence of multilayer composition of both the smaller and the bigger external coverage, these new types of package did not guarantee the greater safety of the drug dealer., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Many studies have focused on the importance of post-mortem computed tomography (PMCT) prior to or in substitution of standard forensic autopsies in case of firearm death. However, due to the fact that PMCT is not routinely performed in all countries, in cases of death abroad it can happen that a CT scan is performed only after a first autopsy. A case of post-mortem re-examination, including the external examination and a post-autopsy computed tomography (PACT), of a gunshot victim of homicide in a foreign country is presented, and the pros and cons of imaging in post-autopsy setting are discussed. PACT could be a tool for carrying out more complete investigations and for obtaining information on bone injuries and foreign bodies trapped within peripheral soft tissues that can be re-analyzed after the arrival of the first autopsy report. Given that the value of information derived may be strongly influenced by the previously performed autopsy, in order to process the definitive considerations it is necessary to compare and interpret the data obtained through PACT with the results of the first autopsy, and to continue the international cooperation effort and the application of international guidelines in order to share information at the repatriation of the corpse., (Copyright © 2017 Elsevier B.V. All rights reserved.)