Control of Recoil Losses in Nanomechanical SiN Membrane Resonators

In the context of a recoil damping analysis, we have designed and produced a membrane resonator equipped with a specific on-chip structure working as a "loss shield" for a circular membrane. In this device the vibrations of the membrane, with a quality factor of $10^7$, reach the limit set by the intrinsic dissipation in silicon nitride, for all the modes and regardless of the modal shape, also at low frequency. Guided by our theoretical model of the loss shield, we describe the design rationale of the device, which can be used as effective replacement of commercial membrane resonators in advanced optomechanical setups, also at cryogenic temperatures

Calibrated quantum thermometry in cavity optomechanics

Cavity optomechanics has achieved the major breakthrough of the preparation and observation of macroscopic mechanical oscillators in peculiarly quantum states. The development of reliable indicators of the oscillator properties in these conditions is important also for applications to quantum technologies. We compare two procedures to infer the oscillator occupation number, minimizing the necessity of system calibrations. The former starts from homodyne spectra, the latter is based on the measurement of the motional sidebands asymmetry in heterodyne spectra. Moreover, we describe and discuss a method to control the cavity detuning, that is a crucial parameter for the accuracy of the latter, intrinsically superior procedure

Diffusion weighted imaging in cystic fibrosis disease: beyond morphological imaging

To explore the feasibility of diffusion-weighted imaging (DWI) to assess inflammatory lung changes in patients with Cystic Fibrosis (CF) METHODS: CF patients referred for their annual check-up had spirometry, chest-CT and MRI on the same day. MRI was performed in a 1.5 T scanner with BLADE and EPI-DWI sequences (b = 0-600 s/mm(2)). End-inspiratory and end-expiratory scans were acquired in multi-row scanners. DWI was scored with an established semi-quantitative scoring system. DWI score was correlated to CT sub-scores for bronchiectasis (CF-CTBE), mucus (CF-CTmucus), total score (CF-CTtotal-score), FEV1, and BMI. T-test was used to assess differences between patients with and without DWI-hotspots

Role of magnetic resonance in characterising extrahepatic cholangiocarcinomas

PURPOSE: The purpose of this study was to evaluate the accuracy of magnetic resonance (MR) in correctly locating and characterising biliary strictures in patients affected by extrahepatic cholangiocarcinoma, identify findings suggestive of the disease, identify lesions with similar MR features and possible criteria for differential diagnosis and establish prospective MR accuracy in diagnosis of malignant obstruction of extrahepatic bile ducts. MATERIALS AND METHODS: We retrospectively reviewed the MR examinations of 39 patients affected by extrahepatic cholangiocarcinoma confirmed by histology or cytology. The studies were evaluated for the following parameters: site of obstruction (hilar, proximal or distal), presence of intra- or extrahepatic dilation of bile ducts, morphology of ductal stenosis (gradual tapering or abrupt ending), morphology of the lesion (mass like or circumferential), dimension, signal intensity before contrast medium administration and lesion enhancement after administration of contrast medium. Finally, we assessed the most useful sequence for the diagnosis. In order to evaluate MR accuracy in the diagnosis of malignant obstruction of extrahepatic bile ducts, we prospectively reviewed MR examinations of 74 patients affected by obstructive jaundice (55 malignant lesions and 19 inflammatory lesions). MR diagnosis was compared with histology or cytology considered as the gold standard. RESULTS: MR allowed identification and localisation of 41/41 extrahepatic cholangiocarcinomas. Fifty-four percent of the lesions showed gradual duct tapering; the remaining lesions showed an abrupt ending. Fifty-six percent of the lesions appeared as a circumferential thickening (infiltrative growth); the remaining lesions had a mass-like appearance (expansile growth). Most lesions were hypo- (49%) or isointense (49%) in T1-weighted sequences and hyper- (49%) or isointense (51%) in T2-weighted sequences. Ninety-five percent of the lesions did not enhance significantly in the arterial phase while 98% showed late enhancement (10 min). The most diagnostic sequence (in 76% of cases) was the late-phase gradient-echo (GRE) T1 fat-saturated sequence. MR had good sensitivity (91%) but poor specificity (47%) in characterising stenosis as malignant, given the large number (10/19) of benign lesions evaluated as neoplastic lesions. CONCLUSIONS: MR almost always identified the cause of stenosis and suggested its neoplastic nature if it exhibited a mass-like appearance (extraductal or growing into the choledochus). On the other hand, lesions with parietal thickening, particularly if smaller than 1 cm, require endoscopic cytology or histology because of the high risk of unnecessary procedures for benign lesions

Bioactive compounds through anaerobic digestion of heterotrophic microalgae residues

Several important biomolecules are available into anaerobically digested effluents that were obtained from the biodiesel production process using heterotrophically grown microalga Chlorella protothecoides. Defatted microalgae residues and crude glycerol may undergo anaerobic digestion, separately and in admixture, providing methane/hydrogen and a digestate exploitable for agriculture applications. Furthermore, industrial interesting bioactive compounds such as polyphenols provided with antioxidant activity can be obtained. Anaerobic process offers a promising chance and can be advantageously combined with algae lipid-extraction techniques in order to make it more sustainable

Planktonic Foraminiferal Biostratigraphy of the Late Eocene and Oligocene in the Palmyride Area, Syria

Three deep exploration wells in the Palmyride area (Syria) have been drilled through Oligocene and Eocene deposits. A detailed micropalaeontological investigation has been performed on the planktonic foraminiferal assemblage from drill cuttings. Standard planktonic foraminiferal zones from P15 to P22 (E15 to O6) have been identified. The test morphology and diversity of the foraminiferal assemblage indicate a general cooling trend during the late Eocene and Oligocene. The specialized Eocene forms (K-mode life strategy) such as turborotaliids, globigerinathekids and hantkeninids become extinct in the uppermost late Eocene. The Oligocene is characterized by the dominance of cooler, opportunistic planktonic foraminifera (r-mode life strategy), such as pseudohastigerinids, chiloguembelinids, globigerinids and tenuitellids. A very low number of benthic foraminifera in late Eocene cuttings implies sedimentation in a deep, open sea environment. A gradual increase of the benthic foraminiferal proportion through the Oligocene indicates shallowing of the sedimentary environment

Cystic tumors of the pancreas

Cystic tumors of the pancreas are less frequent than solid lesions and are often detected incidentally, as many of these lesions are small and asymptomatic. However, they may be associated with pancreatitis or have malignant potential. With advancements in diagnostic imaging, cystic lesions of the pancreas are being detected with increasing frequency. Many lesions can cause a pancreatic cyst, most being non-neoplastic while approximately 10% are cystic tumors, ranging from benign to highly malignant tumors. With increasing experience it is becoming clear that the prevalence of pseudocyst among cystic lesions of the pancreas is lower than usually presumed. A presumptive diagnosis of pseudocyst based on imaging appearance alone can cause a diagnostic error, and neoplastic cysts of the pancreas are particularly susceptible to this misdiagnosis, which can result in inappropriate treatment. Cystic tumors of the pancreas are formed by serous or mucinous structures showing all stages of cellular differentiation. According to the WHO classification, they can be subdivided on the basis of their histological type and biological behavior into benign tumors, borderline tumors, and malignant tumors. Cystic pancreatic tumors can be subdivided into peripheral (serous cystadenomas, mucinous cystic tumors, solid and papillary epithelial neoplasms, cystic islet cell tumors), which do not communicate with the main pancreatic duct, and ductal tumors (mucinous tumor), according to their site of origin. On the basis of imaging criteria alone, it can be very difficult to differentiate non-tumoral cystic lesions from neoplastic ones. The management of these patients is complex, and it is important to correlate imaging findings with knowledge of the patient's symptoms and of the natural history and predictors of malignancy in pancreatic cysts

Variability of Cerebral Deep Venous System in Preterm and Term Neonates Evaluated on MR SWI Venography

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A Java-based Wrapper for Wireless Communications

The increasing number of new applications for mobile devices in pervasive environments, do not cope with changes in the wireless communications. Developers of such applications have to deal with problems arising from the available wireless connections in the given environment. A middleware is a solution that allows to overcome some of these problems. It provides to the applications a set of functions that facilitate their development. In this paper we present a Java-based communication wrapper, called SmartTraffic, which allows programmers to seamlessly use TCP or UDP protocols over Bluetooth or any IP-based wireless network. Developers can use SmartTraffic within their Java applications, thus focusing on the application goals, and leaving out details about how it should interact with the available wireless connection