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Intermittent transport is frequently observed in nature and has been proven to accelerate search processes at both the macroscopic (e.g., animals looking for food) and microscopic scale (e.g., protein-DNA interactions). In living cells, active transport of membrane proteins (e.g., membrane receptors) or intracellular vesicles (organelles) has been extensively studied as an example of intermittent behavior. The intermittent stochastic process is commonly analyzed in terms of first-passage probabilities. Here we derive exact occupation probabilities of intermittent active transport, making such analysis available for image correlation spectroscopy techniques. The power of this new theoretical framework is demonstrated on intracellular trafficking of lipid/DNA nanoparticles in living cells for which we were allowed to quantify switching time scales.

Wrinkling has recently attracted an increasing interest by suggesting a number of unforeseeable applications in many emerging material science and engineering fields. If guided and somehow designed, wrinkles could be in fact used as an alternative printing way for realizing complex surface geometries and thus employed as an innovative bottom-up process in the fabrication of nano- and micro-devices. For these reasons, the prediction of wrinkles of films adhering on flat as well as on structured substrata is a challenging task, genesis and development of the phenomenon being not yet completely understood both when thin membranes are coupled with soft supports and in cases where the geometry of the surfaces are characterized by complex three-dimensional profiles. Here we investigate the experimental formation of new intriguing and somehow unforeseeable wrinkled patterns achieved on periodic structures, by showing prediction through a new hybrid analytical-numerical strategy capable to overcome some common obstacles encountered in modeling film wrinkling on flat and 3D-shaped substrata. The proposed approach, which drastically reduces the computational effort, furnishes a helpful way for predicting both qualitative and quantitative results in terms of wrinkling patterns, magnitude and wavelength, by also allowing to follow the onset of film instabilities and the progressive evolution of the phenomenon until its final stage. Keywords: Thin film, Wrinkling, PDMS substrates, Lithium niobate crystals, FEM simulations

Abstract Although chest X-ray remains a fundamental lung imaging technique, through the years, CT scan has significantly improved our knowledge of the pathophysiological process and currently is the reference lung imaging tool for both a visual and quantitative computer-based analysis. The application of lung CT in the early phase of ARDS has led to changes in the clinical management in up of thirty percent of the patients. Although CT requires the transportation of the patient to the radiological department and exposes the patient to high dose of radiation, given the several information that CT can offer, it should be applied at least one time, in the early phase in all ARDS patients. CT plays an irreplaceable role to describe and assess the lung recruitability and to help a more physiological setting of mechanical ventilation.

Aims: to assess the feasibility and safety of a laparoscopic approach to uPJ obstruction (uPJo) in ectopic pelvic kidneys. Material and Methods: in a retrospective analysis we selected 14 children, aged 6months to 17 years, 12 males, 2 females, who had been treated in our department between January 2004 and June 2011. 9 patients presented ureteropelvic junction obstruction (in 3 cases pelvic stones coexisted) with normal/moderately reduced (≥25%) relative function at radionuclide scan (MAg3), 3 nonfunctioning kidneys associated or not to hypertension, 2 congenital hypo-dysplastic kidneys. the evaluation of each patient involved the medical history, ultrasound examination, VCug, MAg3 diuresis renogram and Mri in some cases. of the patients presenting uPJo, 5 underwent dismembered pyeloplasty with pyelolithotomy, if required, and 4 pelvic derotation with straightening of the uretero-pelvic junction. A previous cystoscopic placement of a double J stent was utilized. this facilitated the identification and dissection around the pelvis. With the patient in trendelenburg position we utilized an umbilical trocar and two trocar in the right and left iliac fossae; an additional trocar, when required, was inserted more cephalad on the midclavear line contralaterally to the lesion. the derotation of ureteropelvic junction was obtained by freeing the kidney’s lower pole and by placing intraperitoneally the junction protected with a double J stent. this was obtained by suturing the peritoneum behind the ureteropelvic junction resulting in a forward rotation of the major axis of the kidney and a straightening of the junction. the 5 patients presenting nonfunctioning ectopic kidneys underwent laparoscopic nephrectomy. While the removal of congenital hypoplasic kidneys resulted easy, the removal of nonfunctioning kidneys was more difficult due to their complex vascular situation and for the embryonic disposition. Results: the operating time varied between 40 to 200 minutes. no patient required conversion to open surgery. the hypertension resolved after nephrectomy in all cases. 2 cases of dismembered pyeloplasty required a placement of double J stent due the recurrence of symptoms and ! patient is waiting for redo operation. the pelvic derotation showed an improvement of diuretic MAg3 renogram and the function remained stable and patiens are symptoms-free. Conclusion: the uPJo in ectopic pelvic kidneys presents a large spectrum of presentation. the laparoscopic approach provides good surgical exposure, and operative times are acceptable compared to those of laparoscopic procedure in anatomically normal kidneys. it has also proved a very useful tool in the non-functioning kidney nephrectomy thank to the help of magnification in the identification of numerous aberrant vessels that are quite often found in the pelvic kidneys. the derotation of the pelvis seems a useful

Abstract Acute brain injury (ABI) covers various clinical entities that may require invasive mechanical ventilation (MV) in the intensive care unit (ICU). The goal of MV, which is to protect the lung and the brain from further injury, may be difficult to achieve in the most severe forms of lung or brain injury. This narrative review aims to address the respiratory issues and ventilator management, specific to ABI patients in the ICU.

Star polymers, consisting of many arms connecting to a central core, represent a branched nanoscale material with compact structure and large surface area. Their synthesis is usually performed by making use of living polymers made by anionic polymerization as arms, and multifunctional compounds as linking agents. In general, polymer blends resulting from the star coupling process exhibit some polydispersity, which is influenced by (i) the polydispersity of the primary chains and (ii) the kinetics of the linking processes to the coupling agent. In the present contribution we develop a mathematical model for the description of the star coupling process in continuous reactors. The proposed model is based on the following statements: (i) the characterization of the MWD of the branched polymer species is accomplished by exploiting a probabilistic approach and (ii) the concentration of the single species is evaluated through implementation of mass balance equations, where the reactions describing the linking of the living polymers to the active branched unit are modelled with first and second order kinetics. The final goal is to predict the MWD shape when varying the operating conditions (i.e.: concentration of polymers and multifunctional agents in the feed flow and residence time).