Induced Chiral Chromonics Confined in Micrometric Droplets

Chirality emergence in biological systems is common but the chiral expression from the molecular to macroscopic level in water-based systems is poorly understood. Among water-based systems, chromonic liquid crystals have recently received a lot of attention due to the spontaneous chirality they show when confined in curved geometries. Confinement of chiral-induced chromonics is not trivial since they are three component systems whose time stability is a delicate thermodynamic balance. In this work, a well-defined periodic Frank–Pryce texture, typical of chiral thermotropic liquid crystals, is observed in microspheres of a chiral induced chromonic embedded in a poly(dimethylsiloxane) matrix. This texture slowly degrades in time and a possible mechanism behind the degradation process is suggested via X-ray diffraction and atomic force microscopy measurements on thin chromonic films. To stabilize this texture and to control the structure periodicity, cations are added to the three components system in an attempt to tune the non-covalent interactions between molecules and supramolecular stacks. The study of the effects of this addition allows for better insight into the molecular interactions that occur in the chiral induced mesophase. This is a crucial point in view of possible biocompatible technological applications.     

Determination of acrylamide in local and commercial cultivar of potatoes from biological farm

This paper reports the results of a preliminary study on the characterization of parameters influencing formation of acrylamide in fried potatoes, from biological cultivation. The formation of acrylamide was investigated in relation to frying in biological extra virgin olive oil and commercial seed oil. Three different cultivars (Rossa di Colfiorito, Quarantina bianca genovese and Kennebec) were chosen. Asparagine, glucose, fructose and sucrose concentrations were determined in potato slice before frying, while acrylamide content was analysed by LC–ESI-MS/MS in the slices fried in seed and extra virgin olive oil. The Kennebec cultivar showed differences in its potential for acrylamide formation, which was primarily related to its relatively high asparagine and reducing sugars contents, respect the other local cultivars (particulary Quarantina). Values of acrylamide below detection limit (LOD) were found in Quarantina bianca genovese cultivar samples fried in extra virgin olive oil and peanuts seed oil and higher in peanuts seed oil fried potatoes of Kennebec cultivar.     

A Framework for JRRM with Resource Reservation and Multiservice Provisioning in Heterogeneous Networks

Inter-working and convergence of heterogeneous wireless networks are paving the way to scenarios in which end users will be capable of using simultaneously services through different Radio Access Technologies (RATs), by means of reconfigurable mobile terminals and different network elements. In order to exploit the potential of these heterogeneous networks scenarios, optimal RAT selection and resource utilization mechanisms are required. As a result, the heterogeneous networks are introducing a new dimension to the Radio Resource Management (RRM) problem, so that new algorithms dealing with the dissimilarities and complementarities of the multiple RATs from a joint perspective have to be considered. In this sense, this paper proposes a Joint Radio Resource Management (JRRM) strategy in a multi-RAT, multicellular and multiservice scenario. An approach based on Fuzzy Neural methodology is presented. Firstly, the way how the proposed Fuzzy Neural framework deals with the multiservice allocation in a heterogeneous scenario is presented. A reinforcement learning algorithm based on neural networks allows guaranteeing a multidimensional QoS focusing on those QoS requirements which mainly affect the user perception of the service. In addition to this, the performances obtained by the Fuzzy Neural JRRM for both real-time and non real-time services, are compared to the ones offered by alternative JRRM strategies. Secondly, special attention is paid to real-time services and to mechanisms to improve their performances. An approach based on predicting future JRRM decisions and on accordingly reserving radio resources for handoff calls is presented. Simulation results will show improvements in terms of both new connection blocking and handoff call dropping probabilities. Finally, the full set of results provides the sufficient insight into the problem to allow stating that the present Fuzzy Neural framework can be a firm candidate for JRRM.

Fiberoptic delivery of laser energy to remove occlusions from ventricular shunts: technical report

OBJECTIVES: Shunts frequently require surgical replacement because occlusions block the ventricular tubing. We have examined the hypothesis that a surgical laser coupled to an optical fiber can deliver sufficient energy to disrupt the occlusion in situ and thus afford a less invasive method of repair. METHODS: Choroid plexus tissue found in shunts explanted from patients, model tissues such as polyacrylamide gel, and animal tissues inserted into shunts were examined. Occlusions were fragmented by pulsed laser energy of 2.09-microm wavelength and 300-microsecond duration delivered via a flexible optical fiber several meters in length. The methods and conditions were similar to those likely to be used for preclinical in vivo studies. RESULTS: Short-lived vapor bubbles generated at the fiber tip disrupted occlusions within the shunt and expelled tissue blocking the inflow holes. Energy requirements to disrupt and remove occlusions in vitro were determined. Laser pulse energies and exposure thresholds that cause intentional damage to shunts also were determined. CONCLUSION: Laser energies needed to disrupt occlusions were below the energy needed to damage the shunt components. Our results show that a strategy using surgical lasers and optical fibers is feasible and suggest that the procedure could be used to repair blocked shunts without requiring surgical replacement.     

Increased density of M1 receptors in the hippocampus of juvenile rats chronically deprived of NGF

Kinins are biologically active peptides that exert their effects by activating two seven transmembrane G-protein coupled receptors termed B1 and B2 which have only about 36% of homology. The major kinin peptide under physiological conditions, bradykinin (BK), modulates renal haemodynamics and function. Under physiological conditions most BK effects involve bradykinin B2-receptors. Studies on the intra-cellular transduction pathways, the regulation of the expression and the localisation of these receptors along the nephron, as well as the first studies on transgenic mice models, have allowed to better define the role of these receptors under physiological and pathological conditions. The role of the renal B1-receptor, induced in a variety of pathologies related to inflammation, is poorly understood. Recent investigations on the molecular mechanism of B1-receptor induction and its detailed renal localisation have shown that under inflammatory conditions this kinin receptor might be of importance. B2-receptors are suggested to be involved in part of the renoprotective effects of angiotensin converting enzyme (ACE)-inhibitors in insulin-dependent diabetes. However, ACE-inhibitor treatment, resulting also in an increased B1-agonist concentration might result in homologous induction and activation of the B1-receptor.     

A domain decomposition technique for finite element based parametric sweep and tolerance analyses of microwave passive devices

A domain decomposition approach is here applied to the finite element solution of a multiport waveguide passive device. The approach allows separating the problem in multiple, coupled subproblems which can be solved individually. By appropriately defining one of these subdomains as containing all the possible variations to be studied it is hence possible to restrict the tolerance analysis to this latter, smaller domain. Numerical results showing the gain in computing time are presented. © 2008 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2009.     

Learning in the “Real World”

In this paper we define and characterize the process of developing a real-world Machine Learning application, with its difficulties and relevant issues, distinguishing it from the popular practice of exploiting ready-to-use data sets. To this aim, we analyze and summarize the lessons learned from applying Machine Learning techniques to a variety of problems. We believe that these lessons, though primarily based on our personal experience, can be generalized to a wider range of situations and are supported by the reported experiences of other researchers.     

An integral method for extremely low frequency magnetic shielding

A novel approach for analyzing conducting shields of extremely low frequency magnetic fields in linear media is presented. It consists of an integral formulation based on the cell method, expressed in terms of network-like loop currents and magnetic vector potential line integrals on the shield surface. This formulation leads to a considerable reduction of field problem variables, thus limiting the amount of allocated memory and speeding-up the numerical procedure compared to other differential and integral techniques. Eddy currents are computed first, then the magnetic vector potential and the magnetic flux density distributions are evaluated by applying the superimposition principle. A detailed comparison between this method and a three-dimensional finite element method code demonstrates the accuracy of the results and the advantages of the method.     

Exercise Preconditioning Blunts Early Atrogenes Expression and Atrophy in Gastrocnemius Muscle of Hindlimb Unloaded Mice

A large set of FoxOs-dependent genes play a primary role in controlling muscle mass during hindlimb unloading. Mitochondrial dysfunction can modulate such a process. We hypothesized that endurance exercise before disuse can protect against disuse-induced muscle atrophy by enhancing peroxisome proliferator-activated receptor-γ coactivator-1α (PGC1α) expression and preventing mitochondrial dysfunction and energy-sensing AMP-activated protein kinase (AMPK) activation. We studied cross sectional area (CSA) of muscle fibers of gastrocnemius muscle by histochemistry following 1, 3, 7, and 14 days of hindlimb unloading (HU). We used Western blotting and qRT-PCR to study mitochondrial dynamics and FoxOs-dependent atrogenes’ expression at 1 and 3 days after HU. Preconditioned animals were submitted to moderate treadmill exercise for 7 days before disuse. Exercise preconditioning protected the gastrocnemius from disuse atrophy until 7 days of HU. It blunted alterations in mitochondrial dynamics up to 3 days after HU and the expression of most atrogenes at 1 day after disuse. In preconditioned mice, the activation of atrogenes resumed 3 days after HU when mitochondrial dynamics, assessed by profusion and pro-fission markers (mitofusin 1, MFN1, mitofusin 2, MFN2, optic atrophy 1, OPA1, dynamin related protein 1, DRP1 and fission 1, FIS1), PGC1α levels, and AMPK activation were at a basal level. Therefore, the normalization of mitochondrial dynamics and function was not sufficient to prevent atrogenes activation just a few days after HU. The time course of sirtuin 1 (SIRT1) expression and content paralleled the time course of atrogenes’ expression. In conclusion, seven days of endurance exercise counteracted alterations of mitochondrial dynamics and the activation of atrogenes early into disuse. Despite the normalization of mitochondrial dynamics, the effect on atrogenes’ suppression died away within 3 days of HU. Interestingly, muscle protection lasted until 7 days of HU. A longer or more intense exercise preconditioning may prolong atrogenes suppression and muscle protection.     

Enhanced bioavailability of itraconazole in hydroxypropyl-beta-cyclodextrin solution versus capsules in healthy volunteers

The bioavailabilities and bioequivalences of single 200-mg doses of itraconazole solution and two capsule formulations were evaluated in a crossover study of 30 male volunteers. The two capsule formulations were bioequivalent. The bioavailabilities of the solutions itraconazole and hydroxyitraconazole were 30 to 33% and 35 to 37% greater, respectively, than those of either capsule. However, the maximum concentrations of the drug in plasma (Cmax), the times to Cmax, and the terminal half-lives were comparable for all three formulations. These data indicate that the bioavailabilities of itraconazole and hydroxyitraconazole are enhanced when administered as an oral solution instead of capsules.