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Alzheimer's disease (AD) is a common neurodegenerative disease that leads to memory and cognitive impairment. Exercise is suggested to prevent it. However, the exact mechanism remains unclear. This study investigated the effect of moderate exercise on cognitive function, oxidative stress and neuro-inflammation in the hippocampal tissue of experimentally-induced AD rats and the possible role of Nuclear Factor Erythroid 2- Related Factor 2 (NRF2) in mediating this effect. Forty adult male albino rats were divided into control and AD groups. Each group is further subdivided into sedentary and exercised ones. AD was induced by intraperitoneal injection with aluminium chloride (70 mg/kg b.w.) for 6 weeks. Exercise protocol was done by swimming 60 min, 5 times a week for 4 weeks. The following parameters were evaluated in all groups: hippocampal tissue assessment of NRF2, amyloid beta, malondialdehyde, interleukin 6 and total antioxidant capacity. Assessment of cognitive performance was done using Morris water maze at weeks 3, 4 and 6 after AD induction. Results revealed significantly lower hippocampal NRF2 and TAC levels with significant higher Aβ, MDA, IL-6 and impaired cognitive dysfunction in sedentary AD rats. These were reversed by swimming exercise. NRF2 was negatively correlated with Aβ, IL-6 and MDA in both AD groups with positive correlation with TAC. In conclusion, moderate swimming exercise exerts neuroprotective effects in AD through improvement of cognitive function, restoration of the antioxidant and anti-inflammatory capacity. The upregulation of NRF2 could mediate these effects. Therefore, targeting NRF2 could be promising as a therapeutic agent for neurodegenerative diseases.

This paper presents performances achieved with InAlGaN/GaN HEMTs with 0.15 µm gate length on SiC substrate. Technology Computer Aided Design simulations were used to optimize the heterostructure. Special attention was paid to the design of the buffer structure. I-V measurements with DC and pulsed bias voltages were performed. CW measurements at millimeter waves were also carried out and are detailed in the following sections. The technology, optimized for power applications up to 45 GHz, demonstrates a current gain cut-off frequency FTof 70 GHz and a maximum available gain cut-off frequency FMAGof 140 GHz. CW Load-pull power measurements at 30 GHz enable to achieve a maximum PAE of 41% associated with an output power density of 3.5 W/mm when biased at VDS= 20 V. These devices, with an improved buffer structure show, reduced recovery time in pulsed operating conditions. These improved characteristics should have a positive impact for pulsed or modulated signal applications.

Silicon drift detectors have been successfully employed in both soft and hard X-ray spectroscopy. The response function to incident radiation at soft X-ray levels has been well studied and modeled, but less research has been published on response functions for these detectors to hard X-ray input spectra above 20 keV. When used with hard X-ray sources a significant low energy, non-peak response exists which can adversely affect detection limits for lighter elements in, for example, X-ray fluorescence spectroscopy. We present a numerical model that explains the non-peak response function of silicon drift detectors to hard X-rays based on incoherent Compton scattering within the detector volume. Experimental results are presented and numerically compared to model results.

This article presents the performances obtained on a $0.15 \mu \mathrm{m}$ gate length InAlGaN/GaN HEMT technology on SiC substrate. This technology uses a back-barrier buffer layer to ensure the confinement of electrons in the channel, which minimizes variations of the drain current when the HEMT devices are submitted to DC or RF pulses. Measurements of the drain current recovery time are shown when the devices are submitted to V DS , V GS or microwave RF pulses. A comparison with an AlGaN/GaN HEMT structure designed with an iron doped buffer layer is proposed.

This paper presents the measurement results of a MMIC power amplifiers (PA), based on InAlGaN/GaN HEMT technology, for Ka band applications. The three-stages MMIC is operating within a bandwidth of [25-31] GHz and demonstrate over this bandwidth a saturated output power of 40dBm. Each stage uses 8x50μm gate width HEMTs fabricated with a 0.I5μm gate length on 70μm thick SiC substrate.

International audience; This paper reports on atomic layer etching of several III-N materials such as GaN, AlN, AlGaN, and InAlGaN based on a sequential surface modification by chlorine adsorption followed by a low energy Ar plasma exposure to remove the modified layer using a reactive ion etching system. A study on the influence of several parameters, such as gas flow rates, removal step duration, RIE power and number of cycles on the etch per cycle, and the root-mean-square roughness, is performed. Low etch per cycle from 0.17 to 1.85 nm/cycle, respectively, for AlGaN and GaN and surfaces as smooth as the as-grown samples were obtained. The developed process is intended to be used for normally off GaN-based high electron mobility transistor processing.

This article discusses papers by Dalal (2016) and Samuels (2016) that explore the tensions between the individual and the group, the complexities of group power dynamics and personal responsibility, and the concept of personal growth or maturation, which this discussant article posits as an outcome of the interplay between individual and social processes.

Purpose: Deformation analysis from 3D echocardiography results in a considerable amount of parameters, for which the conventional statistical approach is cumbersome. We investigate local motion and deformation patterns to determine the parameters of relevance for the study of LV myocardial deformation in the presence of LAD infarct. Methods: The study included 46 patients acquired at max. 5 days after LAD infarct (37 sequences) and at 1-year follow-up (33 sequences), and 46 controls. Patients were selected if they had a LVEF

The acetylcholinesterase inhibitor, galantamine, has shown therapeutic effect in rat model of rheumatoid arthritis. Hence, the current study aims at determining the mode of action of galantamine by examining different synovium-derived microRNAs (miRs) and their related pathogenic pathways. The study also focuses on how parasympathetic and sympathetic pathways in the synovial tissue could affect the mode of action and anti-arthritic effect of galantamine. Chemical sympathectomy was initiated in 12 adjuvant arthritic rats by exposure to 6-hydroxydopamine (6-OHDA; 2 × 50 mg/kg) on day 9 after adjuvant injection and again (2 × 100 mg/kg) one week later. Six rats were treated with galantamine (2.5 mg/kg/day) to explore the influence of sympathetic impairment on galantamine effect. Another twelve additional adjuvant arthritic rats were exposed to the selective α7 nicotinic acetylcholine receptor blocker methylcaconitine citrate (MLA; 5.6 mg/kg/day), 15 min before galantamine treatment. As control, six adjuvant arthritic rats were treated with galantamine alone. Treatment proceeded for 5 days, from day 14 till day 18 post-adjuvant injection. Different miRs and their related pathogenic pathways were examined. Tyrosine hydroxylase (TH) expression was also measured in joint tissue. Galantamine affected the expression of the different miRs and their related parameters. Both, 6-OHDA and MLA, interrupted the anti-inflammatory/anti-arthritic effect of galantamine to different extent. Additionally, TH expression in the synovium was affected by galantamine, suggesting a novel pathogenic target in the treatment of rheumatoid arthritis.

This paper presents the simulated results and first small-signal on-wafer measurements of two MMIC power amplifiers (PA), based on InAlGaN/GaN HEMT technology, for Ka band applications. The two three-stages MMIC1 & MMIC2 are operating within a bandwidth of [27.5–31]GHz and [37–39.5]GHz, respectively and demonstrate over these bandwidths a saturated output power of 40dBm and 38dBm, respectively. Each stage use 8×50μm gate width HEMTs fabricated with a 0.15μm gate length on 70μm thick SiC substrate.

Recent results obtained using InAlGaN/GaN HEMT technology. Material advantages of this heterostructure are depicted and some technological aspects are described. Low lagging effects and high electric field capability is presented. Power densities up to 10W.mm−1 have been obtained at 30GHz. MMIC power amplifiers are briefly reported.

ZusammenfassungThromboembolien sind typische Komplikationen in der Adipositas-Chirurgie. Die prophylaktische Antikoagulation wird generell empfohlen, das optimale Vorgehen bei dieser Patientengruppe ist aufgrund fehlender Studien unklar. Aus dem German Bariatric Surgery Registry wurden für den Zeitraum von 2005–2013 Häufigkeit und Mortalität postoperativer Thromboembolien und Strategien der Antikoagulation ermittelt. Thromboembolien traten bei 0,1 % von 31 668 primären Eingriffen auf. Dieses Ergebnis bestätigt international Daten und wird auf die konsequente Prophylaxe zurückgeführt, denn 98% der Patienten wurden antikoaguliert. Ohne Antikoagulation war das Risiko für eine Lungenembolie dagegen 8-fach erhöht. Tritt ein Ereignis auf, ist die Mortalitätsrate groß, nach Beinvenenthrombose 4,8 % und nach Lungenembolie 12,9 %. Mittel der Wahl zur Prophylaxe sind niedermolekulare Heparine, für neue Antikoagulantien kann keine Empfehlung gegeben werden. Eine Dosiserhöhung der niedermolekularen Heparine sollte bei folgenden Risikofaktoren erwogen werden: BMI >50 kg/m2, Alter >50 Jahre, männlich, venöse Insuffizienz, obstruktives Hypoventilationssyndrom, Rauchen und positive Anamnese für Thromboembolie.

Evidence-based data on optimal approach for prophylaxis of deep venous thrombosis (VTE) and pulmonary embolism (PE) in bariatric operations is discussed. Using antithrombotic prophylaxis, weight adjusted the risk of VTE and its complications have to be balanced with the increased bleeding risk.Since 2005, the current situation for bariatric surgery has been examined by quality assurance study in Germany. As a prospective multicenter observational study, data on the type, regimen, and time course of VTE prophylaxis were documented. The incidences of clinically diagnosed VTE or PE were derived during the in-hospital course and follow up.Overall, 31,668 primary bariatric procedures were performed between January 2005 and December 2013. Most performed operations were 3999 gastric banding (GB); 13,722 Roux-en-Y-gastric bypass (RYGBP); and 11,840 sleeve gastrectomies (SG). Gender (p = 0.945), surgical procedure (p = 0.666), or administration of thromboembolic prophylaxis (p = 0.272) had no statistical impact on the DVT incidence. By contrast, BMI (p = 0.116) and the duration of thromboembolic prophylaxis (p = 0.127) did impact the frequency of onset of DVT.Age, BMI, male gender, and a previous history of VTE are the most important risk factors. The drug of choice for VTE is heparin. LMWH should be given preference over unfractionated heparins due to their improved pharmacological properties, i.e., better bioavailability and longer half-life as well as ease of use. Despite the low incidence of VTE and PE, there is a lack of evidence. Therefore, prospective randomized studies are necessary to determine the optimal VTE prophylaxis for bariatric surgical patients.

We report on the performances of 0.1-μm gate length In Al(Ga)N/GaN HEMT devices on SiC substrate. Measurements results of DC, pulsed I-V, S-parameters and load-pull power performances are presented. Devices exhibited a maximum DC transconductance of 400mS/mm and drain current of 1.2A/mm at Vgs=1V. Cut-off frequencies Ft and Fmag of 60GHz and 140 GHz were obtained. Load-pull power measurements at 30GHz allowed us to achieve an output power density of 3W/mm with 40% of PAE at Vds=15V. Biased at Vds=20V, a maximum saturated output power density of 5W/mm was achieved.

This paper presents the realization and characterization of normally-off recessed MOS-HEMTs on a Ka-band-dedicated AlGaN/GaN epitaxial structure. Previous HEMTs results on this structure feature an output power of 3.5 W/mm with PAE of 39 % at 30 GHz CW. Normally-off operation was achieved through the use of gate recess combined with a Al 2 O3 gate oxide, by a fabrication process compatible with that of normallyon high-frequency power HEMTs. Electrical performances include threshold voltage over 1 V, pulsed drain current in excess of 400 mA/mm and fmax of 35 GHz. Dynamic Ron transients after switching events were investigated, showing thermally-activated increase of Ron over 10 decades of time. Low-frequency output-admittance measurements were also conducted to evaluate the impact of gate recess etching on charge trapping behavior.

The assessment and treatment of urinary incontinence in aged women have age-related specificities that we present from a literature review. Urinary incontinence is most often mixed: stress incontinence and urge incontinence. The coexistence of chronic retention is common and should be taken into account in treatment. Urinary incontinence de novo must find a trigger that will be corrected if possible. The treatment of urinary incontinence in aged women and young women are the same as long as no frailty is present. The definition of frailty is not consensual, but some criteria are regularly cited: age> 80 years, restricted mobility, functional decline, cognitive impairment. In frail aged women, geriatric assessment is necessary to adapt treatment, whether medical or surgical.

Eric Berne proposed but never fully elaborated his ideas about nonconscious human processes and their role in developing a sense of self. In the early work of contemporary psychoanalyst Christopher Bollas, there are parallels to Berne's thinking that can be used to more fully develop Berne's vision of human functioning and maturing.

In this article we report the main experimental results obtained in the framework of the IST ATLAS project regarding the transmission at 40 Gb/s over long terrestrial links, including the frequency conversion of a signal. We report the single-channel 40 Gb/s transmission over a link 500 km long with an amplifier spacing of 100 km, both with G.652 fibers and G.653 fibers by periodically compensating the chromatic dispersion with dispersion-compensating fibers. We report the single-channel transmission at 40 Gb/s, also, after the wavelength conversion of a channel with both PPLN and semiconductor optical amplifier devices. In particular, 500 km distances are obtained with PPLN wavelength conversion and 300 km distances with semiconductor optical amplifiers. Some results have been reported for electronic devices operating at 40 Gb/s.

Thin-film coatings for improved performances of GaN-based HEMTs are investigated. AlN coatings are used either as primary or secondary passivation to reduce the thermal resistance of the transistors.

We report on the development of a 0.15μm gate length InAlN/GaN HEMT on SiC substrate technology for applications in K and Ka-Bands. Measurements results of pulsed I-V, S-parameters, load-pull and RF noise figure are presented. Devices exhibit a maximum DC transconductance of 350mS/mm and Idss of 0.95A/mm. Cut-off frequencies F T and F mag of 45GHz and 100 GHz are reached. Load-pull power measurements at 18GHz allowed us to achieve an output power density of 12W/mm in pulsed mode at Vds=50V. At 30 GHz, 2.5W/mm was measured at Vds=20V. RF noise measurements showed a minimum noise figure of 1.25dB at 20 GHz.

In the present paper we establish some new stability results for interconnected hybrid (resp., discontinuous) dynamical systems. Our results are phrased in terms of the qualitative properties of systems components (subsystems) and constraints imposed on the system interconnecting structure. This viewpoint makes it frequently possible to overcome difficulties encountered in the stability analysis of such systems. The applicability of the present results is demonstrated by means of a specific example.

We first conduct an analysis of the robustness properties of a class of neural networks with applications to associative memories. Specifically, for a network with nominal parameters which stores a set of desired bipolar memories, we establish sufficient conditions under which the same set of bipolar memories is also stored in the network with perturbed parameters. This result enables us to establish a synthesis procedure for neural networks whose stored memories are invariant under perturbations. Our synthesis procedure is capable of generating artificial neural networks with prespecified sparsity constraints (on the interconnecting structure) and with nonsymmetric and symmetric interconnection matrices. To demonstrate the applicability of the present results, we consider several specific examples.

Advances in feedback control theory have inextricably been linked to progress in stability theory, and conversely, the horizons of stability theory have greatly been expanded by the challenges posed in increasingly complex feedback control systems. In the present article we trace the development of stability theory in feedback control by making contact with some of the major milestones in this area.

A qualitative analysis is developed for continuous-time neural networks subjected to random pure structural variations. Simple algebraic conditions are established for both structural exponential stability of x = 0 of the neural network and for estimates of its domain of attraction. Bounds on motions of the neural network in a forced regime are provided. They do not require any information about its actual structure, which can be completely unknown and may vary unpredictably.

We incorporate into a synthesis procedure for a class of discrete-time neural networks an unlearning capability. The proposed technique increases storage capacity while maximizing the domain of attraction of each desired pattern to be stored. Making use of learning and forgetting capabilities, neural networks generated by the method advanced herein are capable of learning new patterns as well as forgetting learned patterns without the necessity of recomputing the entire interconnection weights and external inputs. The unlearning algorithm developed is then utilized off-line to equalize the basins of attraction for each desired pattern to be stored, and to minimize the number of spurious states. Specific examples are given to illustrate the strengths and weaknesses of the methodology advocated herein.

During the implementation process of artificial neural networks, deviations from the desired ideal neural network are frequently introduced. These include parameter perturbations, transmission delays, and interconnection constraints. In the present article, we study the effects of these realities of imperfection on the qualitative behavior of artificial feedback neural networks. To accomplish this, we utilize a specific class of neural networks (Hopfield-like neural networks) with a specific application (the realization of associative memories) as a vehicle for our study. The principal issues which we address concern the effects of parameter perturbations, transmission delays, and interconnection constraints on the accuracy and on the qualitative properties of the network memories. >

The authors develop a design technique for associative memories with learning and forgetting capabilities via artificial feedback neural networks. The proposed synthesis technique utilizes the eigenstructure method. Networks generated by this method are capable of learning new patterns as well as forgetting learned patterns without the necessity of recomputing the entire interconnection weights and external inputs. In many respects, these results constitute significant improvements over the outer product method, the projection learning rule, and the pseudo-inverse method with stability constraints. Several specific examples are given to illustrate the strengths and weaknesses of the methodology advocated. >

The problem of the placement of pumps and the selection of pumping rates are the most important issues in designing contaminated groundwater remediation systems using a pump-and-treat strategy. Three nonlinear optimization formulations are proposed to address these problems. The first problem formulation considers hydraulic constraints and reduces the plume concentration to a specified regulation standard value within a given planning time while minimizing capital cost. The second formulation minimizes residual contaminant in a fixed period under hydraulic contraints only. The third formulation is similar to the second formulation; however, in this formulation the number of pumps is prespecified by using the results from the first formulation. The inclusion of well installation costs in the first problem formulation results in a nonsmooth objective function. For such problems, only local optimum solutions can be expected by the use of conventional nonlinear optimization techniques. In the present paper, the simulated annealing algorithm is used to overcome these difficulties. Specific simulation studies indicate that the method advanced herein is promising and involves acceptable computation times.

Several design techniques that can be used for continuous-time and discrete-time neural networks to realize associative memories are presented. Associative memory is discussed, and neural network models are presented. Some stability concepts are outlined. The applicability of these techniques is demonstrated by means of specific examples that illustrate strengths and weaknesses. >

In this letter we present a new fully index-guided tapered laser design showing a balance between the competing mechanisms modifying the far-field divergence at high operating powers. Simulations and experimental investigations of this device show a low divergence and a stable far-field along a high range of operating conditions, together with negligible astigmatism at high power.

We report the main results from the IST ATLAS project on the transmission techniques for new network infrastructures. We report results on the transmission performance on 4/spl times/40 Gbit/s systems over a 500 km link, including wavelength conversion. We show that wavelength conversion based on a periodically poled lithium niobate (PPLN) device and systems based on N/spl times/40 Gbit/s are now fundamental elements for future transport networks.

In the implementation of artificial neural networks, several limitations are encountered which may affect their qualitative behavior and performance. These include delays, parameter perturbations and interconnection constraints. Depending on the particular type of implementation, more than one of these limitations will usually be encountered simultaneously. In the present paper, we address these issues.

Convergent-beam electron diffraction (CBED) and large-angle convergent-beam electron diffraction (LACBED) techniques are well adapted to the characterization of several types of crystal defects. In fact, dislocations, grain boundaries and stacking faults have already been successfully characterized with these methods. In the present paper, we describe the CBED and LACBED characterization of another type of crystal defect showing a special interest in materials science: antiphase boundaries (APBs). The first part of the paper is devoted to the determination of the effects of antiphase boundaries on CBED and LACBED patterns that could be expected from a theoretical point of view. It indicates that the superlattice excess lines present on these patterns are split into two lines with equal intensity when the incident beam is located on an APB. In the second part, we experimentally test these theoretical predictions on a specimen showing two different known types of antiphase boundaries. In a third part we indicate how these methods could be used to identify unknown APBs in a specimen. Finally, the advantages and disadvantages of both methods for the characterization of antiphase boundaries are discussed.

The authors cite selected papers on neural networks to give a perspective on the present subject matter. They then discuss their own work dealing with the local stability analysis of equilibrium points in the continuous Hopfield model. The authors summarize (global) analysis and synthesis results for a class of neural networks which includes as a special case the continuous Hopfield model. They summarize analysis and synthesis results for a class of neural networks with variable structure, which correspond to the discrete Hopfield model. Also summarized are the analysis and design results for a class of neural networks which are modeled by linear analog circuits that are allowed to operate in saturated modes. Specific applications of neural networks to sorting problems are also presented. >

A discussion is presented of several techniques for the design of continuous-time and discrete-time neural networks for the purpose of realizing associative memories. The applicability of the methods is demonstrated by means of specific examples, and their strengths and weaknesses are pointed out. To introduce the subject and provide required background material, comments on associative memory, neural models, and stability concepts are presented. >

Unlearning capabilities are incorporated into a synthesis procedure for a class of discrete-time neural networks. The proposed technique increases storing capacity while maximizing the domain of attraction of each desired pattern to be stored. Making use of learning, forgetting, and unlearning capabilities, networks generated by the method advanced herein are capable of learning new patterns as well as forgetting learned patterns without the necessity of recomputing all the interconnection weights and external inputs. The unlearning algorithm developed is then utilized to equalize the basins of attraction for each desired pattern to be stored in a given network, and to minimize the number of spurious states. Examples are given to illustrate the strengths and weaknesses of the methodologies. >

We present a robustness analysis result for a class of neural networks. Specifically, we assume a set of bipolar vectors to be memories for a network, and we establish a sufficient condition under which the given set of vectors are also memories of the original network after perturbations on its parameters. >

Presents results for the analysis and synthesis of a class of neural networks with sparse connections. The authors' design procedure guarantees to synthesize neural networks with arbitrarily predetermined sparse connection structures and to store a given set of desired bipolar patterns. >

We first conduct an analysis of the robustness properties of a class of neural networks with applications to associative memories. Specifically, for a network with nominal parameters storing a set of desired bipolar memories, we establish sufficient conditions under which the same set of bipolar memories is also stored in the network with perturbed parameters. This result enables us to establish a design procedure for neural networks whose stored memories are invariant under perturbations. Our design procedure is capable of generating artificial neural networks with prespecified sparsity constraints and in particular, is applicable in the design of cellular neural networks for associative memories. >

The authors develop a design technique for associative memories with learning and forgetting abilities via artificial feedback neural networks. The proposed method utilizes the theory of large-scale dynamical systems, instead of the usual energy methods. Networks synthesized by this design method are capable of learning new patterns as well as forgetting existing patterns without the necessity of recomputing the entire interconnection weights and external inputs. The method employs the properties of pseudo-inverse matrices to iteratively solve systems of linear equations, and provides significant improvements over the outer product method and the projection learning rule. Several specific examples are given to illustrate the strengths and weaknesses of the methodology. >

In contrast to the usual types of neural networks which utilize two states for each neuron, a class of synchronous discrete-time multilevel threshold neural networks is developed. A qualitative analysis and a synthesis procedure of the class of neural networks constitute the principal contributions of this work. The applicability of the class of neural networks is demonstrated by means of a gray-level image processing example in which each neutron of the present model assumes one of 16 values. In doing so, the number of neurons and the number of interconnections are reduced, when compared to the usual binary state networks. >

First formulates a definition of hybrid dynamical system which covers a very large number of classes of hybrid systems and which is suitable for the qualitative analysis of such systems. Next, the authors present several specific examples of hybrid dynamical systems.

A synthesis procedure for designing nonsymmetric cellular neural networks (CNN) with a predetermined local interconnection structure that will store a set of desired bipolar vectors as memory points is presented. A specific case of constructing Chinese characters is presented to demonstrate the applicability of the results. Simulation results show that all the vectors corresponding to 50 commonly used Chinese characters are reachable memory vectors of the synthesized CNN. >

Some neural network models qualitative analysis of analogue Hopfield-type neural networks - global results stability analysis of linear systems operating on a closed hypercube - system (M) qualitative analysis of Hopfield-type neural networks - local results qualitative effects of parameter perturbations qualitative effects of time delays.