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BACKGROUND: Stereotactic radiosurgery has become a common treatment approach for small-to-medium size vestibular schwannomas. OBJECTIVE: To evaluate relationship between time (beam-on and treatment) and risk of hearing decline after stereotactic radiosurgery for vestibular schwannomas in patients with Gardner–Robertson (GR) baseline classes I and II. METHODS: This retrospective longitudinal single-center study included 213 patients with GR I and II treated between June 2010 and December 2019. Risk of passing from GR classes I and II (coded 0) to other classes III, IV, and V (coded 1) and the increase in pure tone average (continuous outcome) were evaluated using a mixed-effect regression model. Biologically effective dose (BED) was further assessed for an alpha/beta ratio of 2.47 (Gy2.47). RESULTS: Binary outcome analysis revealed sex, dose rate, integral dose, time [beam-on time odds ratio 1.03, P = .03, 95% CI 1.00-1.06; treatment time (P = .02) and BED (P = .001) as relevant. Fitted multivariable model included the sex, dose rate, and BED. Pure tone average analysis revealed age, integral dose received by tumor, isocenter number, time (beam-on time odds ratio 0.20, P = .001, 95% CI 0.083-0.33) and BED (P = .005) as relevant. CONCLUSION: Our analysis showed that risk of hearing decline was associated with male sex, higher radiation dose rate (cutoff 2.5 Gy/minute), higher integral dose received by the tumor, higher beam-on time ≥20 minutes, and lower BED. A BED between 55 and 61 was considered as optimal for hearing preservation. De tre sista författarna delar sistaförfattarskapet

Travelling wave parametric amplifiers (TWPAs) made from highly nonlinear reactive superconducting thin films have been demonstrated to be a viable technology for various quantum applications, including fundamental physics experiments such as astronomy and axion dark matter searches, as well as commercial applications like quantum computational and communication systems. In this paper, we present the design of a kinetic inductance TWPA comprising a patterned titanium nitride film that can operate at 0.3K to demonstrate the feasibility of operation closer to 1K temperature, paving the way to achieve even higher bath temperature operation. We discuss in detail the design of our TWPA, along with the predicted gain-bandwidth product and other characteristics. We perform the preliminary experimental investigation of the thin film properties and compare that with the simulated results. We found that there are several discrepancies between the measured and the predicted behaviour of the thin film. We attribute these differences to the fact that the fabricated thin film has a different gap voltage, resistivity and thickness to what we expected. With a new set of estimated parameters, we successfully reproduce the measured transmission profile. We further show that by utilising bridges to ensure equipotential grounds for the CPW lines, we are able to reduce the rippling effect and achieve a higher gain with broader bandwidth. We expect that our TWPA can achieve higher than 20 dB gain from approximately 0–8 GHz.

Research was undertaken to establish an inventory of ticks on dogs in the north east of Algeria. In the first aspect of study, a survey aims to identify of Ixodidae infesting the dogs in bioclimatic different areas and to determine the risk factors. This work took place between 2006 and 2012. The results of the collections show that all the dogs, which were the subject of this survey, are infested by ticks during the period between March and August in different areas of the northeastern of Algeria. Rhipicephalus sanguineus is the predominant tick species. It has been observed with a frequency of 88 % in the area of El-Tarf, 100 % in Souk-Ahras, 95 % in the Tébessa region and 72 % in Guelma, (average of 89 %). Climatic conditions seem to play the essential role for this distribution of ticks. The other tick species collected are: Ixodes ricinus, Rhipicephalus turanicus, Haemaphysalis punctata and Hyalomma anatolicum. The latter were present with very low a proportion, which gives them the appearance of accidental parasitism in dogs. Rhipicephalus sanguineus has significant infestation intensity in spring and summer, peaking in August in the semi-arid region (Souk-Ahras). In humid regions (El-Tarf), the peak of infestation recorded by this arthropod is in April. The second aspect of study of the seasonal dynamics of Rhipicephalus sanguineus shows the seasonal nature (Spring-Summer) of the brown tick of dog.

Let G and H be two simple undirected graphs. An embedding of the graph G into the graph H is an injective mapping f from the vertices of G to the vertices of H. The study of graph embedding arises naturally in a number of computational problems: portability of algorithms across various parallel architectures and layout of circuits in VLSI. Akers and Krishnamurthy proposed the pancake as an alternative to the hypercube and its variations for interconnecting processors in parallel computers.

Sliding mode control (called SMC) is a control scheme well known with its robustness against modelling uncertainties and external disturbances. This is achieved by using a high frequency switching part into the control law. However, this leads to the appearing of an undesirable chattering phenomenon around the sliding surface. This generates a serious drawback when implementing the controller in real time. So, the higher order sliding mode controller (HOSMC) can be used to overcome these drawbacks. In this paper, we present a novel technique of HOSMC for uncertain nonlinear systems and to show its high performances, robustness and stability a comparative study with three well know techniques of HOSMC is investigated. Besides, to improve the new strategy of control we propose a fuzzy supervision of the controller gain. This makes the controller free chattering and provides an exponential stability on the sliding surface and guarantees the robustness against uncertainties and external matched disturbances. The proposed approach is applied to a model of a car to ensure a robust tracking of a prescribed reference trajectory. Numerical simulations are developed to show the effectiveness of the proposed approaches.

The main topic of this paper is the problem of constructing unknown inputs observers for MIMO nonlinear switched systems. The idea is to switch between different observers to estimate the unknown states and the non-measured inputs for every transient’s periods with the choice of various values of the gain to reduce the error estimation. Theoretical stability analysis is derived to ensure the convergence of the designed observer. Instead, simulation results on a quadruple tank process are given in order to assess the efficiency of the proposed hybrid observers.

A new strategy of control is formulated for chaos synchronisation of non-identical chaotic systems with different orders using the Borne and Gentina practical criterion associated with the Benrejeb canonical arrow form matrix, to drift the stability property of dynamic complex systems. The designed controller ensures that the state variables of controlled chaotic slave systems globally synchronise with the state variables of the master systems, respectively. Numerical simulations are performed to illustrate the efficiency of the proposed method.

An advanced seismic compression technique is proposed to manage seismic data in a world of ever increasing data volumes in order to maintain productivity without compromising interpretation results. A separable 3-D discrete wavelet transform (DWT) using long biorthogonal filters is used. The computation efficiency of the DWT is improved by factoring the wavelet filters using the lifting scheme. In addition, the lifting scheme offers: 1) a dramatic reduction of the required auxiliary memory, 2) an efficient combination with parallel rendering algorithms to perform arbitrary surface and volume rendering for interactive visualization, and 3) an easy integration in the parallel I/O seismic data loading routines. The proposed technique is tested on a seismic volume from the Stratton field in South Texas. The resulting 3-level multiresolution decomposition yields 21 detail sub-volumes and a unique low-resolution sub-volume. The detail wavelet coefficients are quantized with an adaptive threshold uniform scalar quantizer (TUSQ). The scale-dependent thresholds are determined with the Stein unbiased risk estimate (SURE) principle. As the approximation coefficients represent a smooth low-resolution version of the input data they are only quantized using a uniform scalar quantizer (USQ). Finally a runlength plus a Huffman encoding are applied for binary coding of the quantized coefficients.

In this work, we propose a novel technique of higher order sliding mode control in order to solve the problem of chattering phenomenon which appears, generally, with standard sliding mode controller. The proposed approach provides an exponential stability on the sliding surface and guarantees the robustness of the closed loop system against uncertainties and external matched disturbances. The resulting controller has been applied to control an induction motor. Numerical simulations are developed to show the effectiveness of the proposed approach.

BACKGROUND: Interventions have been developed to reduce overestimations of substance use among others especially for alcohol and among students. Nevertheless there is a lack of knowledge on misperceptions of use for substances other than alcohol. We studied the prevalence of misperceptions of use for tobacco cannabis and alcohol and whether the perception of tobacco cannabis and alcohol use by others is associated with one's own use. METHODS: Participants (n=5216) in a cohort study from a census of 20 year old men (N=11819) estimated the prevalence of tobacco and cannabis use among peers of the same age and sex and the percentage of their peers drinking more alcohol than they did. Using the census data we determined whether participants overestimated accurately estimated or underestimated substance use by others. Regression models were used to compare substance use by those who overestimated or underestimated peer substance with those who accurately estimated peer use. Other variables included in the analyses were the presence of close friends with alcohol or other drug problems and family history of substance use. RESULTS: Tobacco use by others was overestimated by 46.1 and accurately estimated by 37.3 of participants. Cannabis use by others was overestimated by 21.8 and accurately estimated by 31.6 of participants. Alcohol use by others was overestimated by more than half (53.4) of participants and accurately estimated by 31.0. In multivariable models compared with participants who accurately estimated tobacco use by others those who overestimated it reported smoking more cigarettes per week (incidence rate ratio [IRR] [95 CI] 1.17 [range 1.05 1.32]). There was no difference in the number of cigarettes smoked per week between those underestimating and those accurately estimating tobacco use by others (IRR [95 CI] 0.99 [range 0.84 1.17]). Compared with participants accurately estimating cannabis use by others those who overestimated it reported more days of cannabis use per month (IRR [95 CI] 1.43 [range 1.21 1.70]) whereas those who underestimated it reported fewer days of cannabis use per month (IRR [95 CI] 0.62 [range 0.23 0.75]). Compared with participants accurately estimating alcohol use by others those who overestimated it reported consuming more drinks per week (IRR [95 CI] 1.57 [range 1.43 1.72]) whereas those who underestimated it reported consuming fewer drinks per week (IRR [95 CI] 0.41 [range 0.34 0.50]). CONCLUSIONS: Perceptions of substance use by others are associated with one's own use. In particular overestimating use by others is frequent among young men and is associated with one's own greater consumption. This association is independent of the substance use environment indicating that even in the case of proximity to a heavy usage group perception of use by others may influence one's own use. If preventive interventions are to be based on normative feedback and their aim is to reduce overestimations of use by others then the prevalence of overestimation indicates that they may be of benefit to roughly half the population; or in the case of cannabis to as few as 20. Such interventions should take into account differing strengths of association across substances.

The combination of the non-linear generalised predictive control (NGPC) and the adaptive interconnected observer (AIO) is considered for the design of the output feedback predictive controller. Since the induction motors (IMs) are intensively used in applications requiring high dynamic performance, the algorithm developed is potentially useful for a fully decoupling in speed and flux magnitude regulation. Indeed, in a first step the state-feedback controller is given, which stems from the approximation of the output tracking error in the receding horizon by its Taylor-series expansion is given. In a second step, the AIO property is exploited in order to avoid the problem of parameters uncertainly and state unavailability during the drive motor, with realising a suitable tracking of trajectories for the system output. This results in a sensorless control of the induction motors, whose rotor and stator resistances, the load torque, the rotor flux and mechanical speed are simultaneously recovered by profiting only from the measurements of the stator current. Effectiveness of the proposed observers and the performance of the controller are confirmed by simulation results.

International audience; Background: The use of natural products as anticancer and antioxidant agents has a long history. Several chemotherapy drugs were isolated from medicinal plants. Objective: The present study was aimed to provide information on cytotoxic and antioxidant activity of cyclohexane, dichloromethane and methanol extracts of Corrigiola telephiifolia.Materials and method: The plant roots were dried, powdered and extracted successively by cold maceration with: cyclohexane, dichloromethane and methanol for 48h. All extracts have been assessed for antioxidant activity against DPPH (1,1-diphenyl-2-picrylhydrazyl) radical and cytotoxic activity against murine colon adenocarcinoma CT-26 and melanoma cell lines WM-266.Results: The dichloromethane extract exhibited potent cytotoxicity with an IC50 of 80 ± 4.56 for CT-26 cells and 70 ± 6.1 µg/ml for WM-266 cells. The extracts exhibited moderate antioxidant activity with IC50 value of 10.53 µg/ml of the dichloromethane extract compared to the IC50 value of 4.71 ± 0.83 µg/ml as shown by the reference antioxidant Trolox.Conclusion: The potential activity of Corrigiola telephiifolia root extract may due to their phytochemical constituents, these species could be considered as potential sources of anticancer compounds. Further studies are necessary for chemical characterization of the active principles and more extensive biological evaluations.

International audience; Metformin is an orally administered drug that lowers blood glucose and improves insulin sensitivity in patients with non insulin-dependent diabetes. Although the antihyperglycemic effect of metformin has been extensively studied, its cellular mechanism(s) of action (including the effect on enterocyte) remains to be defined. This study was designed to examine the effect of metformin on glucose transporters in enterocyte. Na(+)-dependent glucose transporter-1 (SGLT-1) activity was followed as glucose-induced short-circuit current (Isc) in Ussing chambers. The effect of metformin (10 micromol/L, 3 min) on transmural glucose transport was studied in isolated rat jejunal loops. Its impact on abundance of transporters SGLT-1 and GLUT2 in jejunal brush border membranes (BBM) and its effect on the phosphorylation of AMP-activated protein kinase (AMPK) alpha2 subunit was studied by western blot. Acute effect of metformin was also measured in vivo by oral glucose tolerance test (OGTT). Metformin markedly inhibited glucose-induced Isc (approximately 77%) after mucosal addition. In addition, metformin reduced the glucose-induced abundance of SGLT-1 in BBM and increased those of GLUT2, concomitantly increasing the phosphorylation of intracellular AMPKalpha2. This effect of metformin was also observed using non-metabolizable sugar alpha3-O-methyl glucose. Transmural glucose transport measured in vitro was increased by 22% under metformin. Finally, oral metformin markedly increased glucose tolerance in OGTT. In conclusion, metformin slightly increases intestinal glucose absorption by inducing a re-distribution of glucose transporters in BBM through AMPK control in enterocyte. In addition to its action to other splanchnic tissues, this could constitute a peripheral signal contributing to the beneficial effect of metformin on glucose tolerance.