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A quinoa (Chenopodium quinoa Willd.) é uma planta da família Chenopodiaceae, cultivada em diferentes regiões na América do Sul, especialmente nos Andes, tendo sido recentemente introduzida na Europa, América do Norte, Ásia e África. No Brasil, seu consumo é limitado devido ao alto custo do grão importado, ao desconhecimento da população e à baixa disponibilidade de cultivares adaptadas às condições locais. O presente trabalho tem por objetivo revisar os aspectos relacionados à composição química, nutricional e antinutricional de quinoa e suas principais formas de consumo. O valor nutritivo deste grão é superior ao da maioria dos cereais consumidos no Brasil. Os fatores antinutricionais presentes na semente de quinoa são saponinas (principal), ácido fítico, taninos e inibidores de tripsina. Estas substâncias encontram-se presentes em maior concentração nas camadas mais externas do grão, sendo, contudo, facilmente removidas por métodos úmidos ou secos e tratamento térmico. Comercialmente, encontram-se disponíveis os grãos, integral ou polido, e farinhas, podendo ser aplicados em diversos produtos, seja como ingrediente principal ou em combinação com outros, na preparação de diferentes derivados alimentícios (massas alimentícias, snacks, flocos, farinhas instantâneas, produtos de panificação, dentre outros).

The first direct measurement of the dependence on target nuclear mass of the average squared transverse momentum of pi+, pi-, and K+ mesons from deep-inelastic lepton scattering is obtained as a function of several kinematic variables. The data were accumulated at the HERMES experiment at DESY, in which the HERA 27.6 GeV lepton beam was scattered off several nuclear gas targets. The average squared transverse momentum was clearly observed to increase with atomic mass number. The effect increases as a function of Q**2 and x and remains constant as a function of both the virtual photon energy nu and the fractional hadron energy z, except that it vanishes as z approaches unity., Comment: 6 pages, 2 figures

Exclusive electroproduction of π+ mesons was studied by scattering 27.6 GeV positrons or electrons off a transversely polarized hydrogen target. The single-spin azimuthal asymmetry with respect to target polarization was measured as a function of the Mandelstam variable t, the Bjorken scaling variable xB, and the virtuality Q2 of the exchanged photon. The extracted Fourier components of the asymmetry were found to be consistent with zero, except one that was found to be large and that involves interference of contributions from longitudinal and transverse virtual photons.

The exclusive electroproduction of rho-0 mesons was studied with the HERMES spectrometer at the DESY laboratory by scattering 27.6 GeV positron and electron beams off a transversely polarized hydrogen target. Spin density matrix elements for this process were determined from the measured production- and decay-angle distributions of the produced rho-0 mesons. These matrix elements embody information on helicity transfer and the validity of s-channel helicity conservation in the case of a transversely polarized target. From the spin density matrix elements, the leading-twist term in the single-spin asymmetry was calculated separately for longitudinally and transversely polarized rho-0 mesons. Neglecting s-channel helicity changing matrix elements, results for the former can be compared to calculations based on generalized parton distributions, which are sensitive to the contribution of the total angular momentum of the quarks to the proton spin., 7 pages, 5 figures

The momentum and helicity density distributions of the strange quark sea in the nucleon are obtained in leading order from charged-kaon production in deep-inelastic scattering on the deuteron. The distributions are extracted from spin-averaged K+/- multiplicities, and from K+/- and inclusive double-spin asymmetries for scattering of polarized positrons by a polarized deuterium target. The shape of the momentum distribution is softer than that of the average of the ubar and dbar quarks. In the region of measurement 0.02 < x < 0.6 and Q^2 > 1.0 GeV^2, the helicity distribution is zero within experimental uncertainties., 5 pages, 5 figures, 1 table; text slightly expanded, 10 references added

In this paper, a first prototype of a multifunctional tactile sensor using ionic polymer metal composites (IPMCs) is proposed, designed, and tested. Two IPMC strips are used, one as an actuator and one as a sensor, both positioned in a cantilever configuration; working together they enable the system to detect the presence of a material in contact with it and to measure its stiffness. These sensing capabilities can be exploited in various biomedical applications, such as catheterism, laparoscopy and the surgical resection of tumors. Moreover, the simple structure of the proposed tactile sensor can easily be extended to devices in which a sensing tip for exploration of the surrounding environment is required. Compared with other similar tools, the one proposed works with a very low-power supply (the order of magnitude being a few volts), it needs very simple electronics, it is very lightweight and has a low cost.

This work describes a device designed and built to detect the inclination of a body, based on two emerging smart materials: ionic polymer–metal composites (IPMCs) and ferrofluids. The system is bio-inspired and simulates the behavior of the vestibular labyrinth, a biological component of living beings, situated in the inner ear and devoted to perception of the angular acceleration the head is subjected to. In the same way the proposed system is able to reveal its inclination by detecting the position of a ferrofluid mass inside a circular tube. The detection is performed by using the sensing properties of IPMCs, cut into opportunely sized strips, acting as ciliate cells in the tube. The system, details of which are given in the text, is totally new and combines two innovative technologies, IPMCs and ferrofluids, that allow good performance to be obtained at a low cost. The experimental setup is presented and several results are shown and discussed.

A series of semi-inclusive deep-inelastic scattering measurements on deuterium, helium, neon, krypton, and xenon targets has been performed in order to study hadronization. The data were collected with the HERMES detector at the DESY laboratory using a 27.6 GeV positron or electron beam. Hadron multiplicities on nucleus A relative to those on the deuteron, R_A^h, are presented for various hadrons (\pi^+, \pi^-, \pi^0, K^+, K^-, p, and \bar{p}) as a function of the virtual-photon energy \nu, the fraction z of this energy transferred to the hadron, the photon virtuality Q^2, and the hadron transverse momentum squared p_t^2. The data reveal a systematic decrease of R_A^h with the mass number A for each hadron type h. Furthermore, R_A^h increases (decreases) with increasing values of \nu (z), increases slightly with increasing Q^2, and is almost independent of p_t^2, except at large values of p_t^2. For pions two-dimensional distributions also are presented. These indicate that the dependences of R_A^{\pi} on \nu and z can largely be described as a dependence on a single variable L_c, which is a combination of \nu and z. The dependence on L_c suggests in which kinematic conditions partonic and hadronic mechanisms may be dominant. The behaviour of R_A^{\pi} at large p_t^2 constitutes tentative evidence for a partonic energy-loss mechanism. The A-dependence of R_A^h is investigated as a function of \nu, z, and of L_c. It approximately follows an A^{\alpha} form with \alpha \approx 0.5 - 0.6., Comment: 33 pages, 12 figures

This paper presents an innovative wormlike robot controlled by cellular neural networks (CNNs) and made of an ionic polymer-metal composite (IPMC) self-actuated skeleton. The IPMC actuators, from which it is made of, are new materials that behave similarly to biological muscles. The idea that inspired the work is the possibility of using IPMCs to design autonomous moving structures. CNNs have already demonstrated their powerfulness as new structures for bio-inspired locomotion generation and control. The control scheme for the proposed IPMC moving structure is based on CNNs. The wormlike robot is totally made of IPMCs, and each actuator has to carry its own weight. All the actuators are connected together without using any other additional part, thereby constituting the robot structure itself. Worm locomotion is performed by bending the actuators sequentially from "tail" to "head," imitating the traveling wave observed in real-world undulatory locomotion. The activation signals are generated by a CNN. In the authors' opinion, the proposed strategy represents a promising solution in the field of autonomous and light structures that are capable of reconfiguring and moving in line with spatial-temporal dynamics generated by CNNs.

The astrophysically relevant 3 He ( d , p ) 4 He reaction was indirectly studied by means of the Trojan Horse Method applied to the 6 Li ( 3 He , pα ) 4 He three body process performed at 5 and 6 MeV. The bare astrophysical S(E)-factor extracted in Modified Plane Wave Born Approximation was compared with the free behaviour and an independent estimate of the screening potential was obtained, confirming the discrepancy with the adiabatic limit.

The increasing pressure on the development time of new materials and devices has changed the modelling and design process over the years. In the past, they mainly consisted of experimentation and physical prototyping. Clearly, it is hard to incorporate changes in finished prototypes, while producing a variety of different prototypes at once may be very expensive. To this aim, computer simulation models such as circuit design models and continuous system simulation models are widely used in engineering modelling, design and analysis. The studies towards a better understanding of complex systems require quantitative model development, making optimisation and experimental data fitting tools indispensable. In this framework, the modelling of ionic polymer-metal composites (IPMCs) is studied. In particular, this paper deals with simulation-optimisation issues arising in the model calibration of a particular IPMC-based actuator in air. We consider a non-linear dynamical model of the device, with lumped parameters, able to estimate the IPMC actuator absorbed current, together with the mechanical quantities of interest, which, in the case under study, are the free deflection and/or the blocked force. Two optimisation problems have been formulated, focussing on different stages of the model parameters identification. The strategies adopted to solve the problems allow to achieve some promising – although preliminary – results.

Azimuthal single-spin asymmetries of lepto-produced pions and charged kaons were measured on a transversely polarized hydrogen target. Evidence for a naive-T-odd, transverse-momentum-dependent parton distribution function is deduced from non-vanishing Sivers effects for pi+, pi0, and K+, K-, as well as in the difference of the pi+ and pi- cross sections., Comment: 6 pages, 4 figures

Azimuthal asymmetries in exclusive electroproduction of real photons are measured for the first time with respect to transverse target polarisation, providing new constraints on Generalized Parton Distributions. From the same data set on a hydrogen target, new results for the beam-charge asymmetry are also extracted with better precision than those previously reported. By comparing model calculations with measured asymmetries attributed to the interference between the deeply virtual Compton scattering and Bethe-Heitler processes, a model-dependent constraint is obtained on the total angular momenta carried by up and down quarks in the nucleon., 24 pages, 10 figures, 2 tables; 1 figure,3 references added, slight text change

The exclusive electroproduction of pi+ mesons was studied with the Hermes spectrometer at the DESY laboratory by scattering 27.6 GeV positron and electron beams off an internal hydrogen gas target. The virtual-photon cross sections were measured as a function of the Mandelstam variable t and the squared four momentum -Q^2 of the exchanged virtual photon. A model calculation based on Generalized Parton Distributions is in fair agreement with the data at low values of |t| if power corrections are included. A model calculation based on the Regge formalism gives a good description of the magnitude and the t and Q^2 dependences of the cross section., Comment: 7 pages, 5 figures, revised text

In this work the design and realization of an artificial vestibular system demonstrator is presented. The whole system is biologically inspired to the human vestibular apparatus. The mototransduction capabilities of ionomeric polymer-metal composite (IPMC) have been used in order to develop the prototype [1]. The reported results are the starting point to the future design and development of a miniaturized artificial vestibular system, integrating biocompatible materials and all-organic electronic devices [2].

The feasibility of inclusive neutron production measurements in reactions induced by low-intensity radioactive beams using a 4π thermalization counter is studied. The time response of the detector is investigated experimentally by a technique that results in an enhanced sensitivity to weak components with long capture times. Complementary Monte Carlo simulations are presented. The capture time response is found to be independent on the neutron energy above 0.1 MeV. The capability of the capture time information in the unambiguous identification of neutron signals correlated to the projectile arrival on the target even in the presence of an intense background contamination is shown. As an application case, the 8 Li( 4 He,n) 11 B reaction at the Big-Bang temperature is commented.

Ionic Polymer Metal Composites (IPMCs) are active materials that exhibit interesting bidirectional electromechanical coupling phenomena: by bending an IPMC strip a voltage output is obtained, while a voltage input is able to cause the strip to bend. They are of increasing interest in innovative applications due to several advantages respect to competing technologies (SMA, piezoelectric, etc.), such as the possibility to be used both as moving actuators and sensors, their lightness and the low actuation voltage. In this work a new experimental setup to investigate IPMC behaviour as sensors, in a wide range of frequency, is described and some results of the analysis of sensing properties of IPMCs strips are presented. In particular, attention is focused on the frequency analysis of the IPMCs in a cantilever bender configuration.

In this paper, an integrated motion sensor-actuator system is presented. The innovative system consists of a couple of ionic polymer metal composite (IPMC) strips working respectively as a sensor and as an actuator, showing the capability of this material to realize smart devices. Although a number of applications have been proposed to show that IPMCs can work both as actuator or as sensor, none has been produced that exploits both properties in one application. The developed system is composed of a sensor that monitors the vibrations of a membrane under the effects of external disturbances. The sensor output is manipulated and sent to the actuator to reduce vibrations of the membrane itself. Experimental results show that the vibrations of the system are reduced when the control loop is closed.

Based on a previous paper presented at EAPAD Conference on 2005 and supported by the European Community by the research project ISAMCO (Ionic polymer metal composite as Sensors and Actuators for Motion COntrol, 2004-2006) inside the sixth Framework Program, the proposed paper goes on describing the results about the characterization of IPMC materials as motion actuators, obtained by using an improved infrared-based system designed, realized and characterised to this aim. The system was required to detect both the IPMC absorbed current and its consequent deflection, under the effect of the applied voltage. The deflection is detected by the IR system, that uses a differential configuration in order to reduce non-linearity, peculiar to IR devices. The measurement system is used to identify and then validate a model, proposed to describe the IPMC actuator behaviour in a wide range of operating conditions. The model was obtained by adopting a grey box approach. By acquiring the signals involved: the applied voltage, the absorbed current and the IPMC displacement, for different inputs such as pulses, sinusoidal waves (with varying frequency and amplitude) and noise, and by post-processing these signals, all the parameters relative to the IPMC actuator were identified and several tests were performed in order to compare the behaviour of the actuator as predicted by the model with the experimental one. The obtained results show a very good accordance between the simulated and the real actuator response, hence represent a good validation of the proposed model.

Ionic Polymer Metal Composites or IPMCs are innovative materials, light and soft, that show very interesting electromechanical properties to be used in several fields of research, such as robotics, measurements, biomedics. In this paper details on IPMCs will be given: from their state of the art to their modeling and characterization; tools and equipments, designed and realized to perform measurements on the IPMCs will be presented.

This paper introduces a comprehensive model of sensors based on ionic polymer metal composites (IPMCs) working in air. Significant quantities ruling the sensing properties of IPMC-based sensors are taken into account and the dynamics of the sensors are modelled. A large amount of experimental evidence is given for the excellent agreement between estimations obtained using the proposed model and the observed signals. Furthermore, the effect of sensor scaling is investigated, giving interesting support to the activities involved in the design of sensing devices based on these novel materials. We observed that the need for a wet environment is not a key issue for IPMC-based sensors to work well. This fact allows us to put IPMC-based sensors in a totally different light to the corresponding actuators, showing that sensors do not suffer from the same drawbacks.

The electrical behavior of an ionic polymer-metal composite (IPMC), when a voltage is applied across its thickness, is investigated. IPMCs are new materials of increasing interest, to implement artificial muscles in robotic applications, and to implement displacement sensors in measurement fields. They are particularly light and they deform if electrically stimulated with a very low voltage; on the other hand they produce a voltage if mechanically bent. An understanding of the phenomena involved in electromechanical energy conversion may address research activity toward the building of innovative devices where both sensing and actuating functions could be integrated in the same material. The paper illustrates a model that describes the electrical behavior of an IPMC as an actuator using an equivalent circuit. It is a totally new nonlinear lumped parameter model which is able to describe all the phenomena observed in the flow of electrical current through the material, including nonlinear phenomena. The model has been validated by a large set of comparisons between simulations and experimental data. In all the cases analyzed the simulations agree with the experimental data.

Ionic Polymer Metal Composites or IPMCs are emerging materials belonging to EAP class. They are of increasing interest in innovative applications due to several advantages respect to competing technologies (SMA, piezoelectric, etc.), such as the possibility to be used both as moving actuators and sensors, their lightness and the low actuation voltage. On the other hand their behaviour is not fully known and it is still subjected to deep investigations. In this perspective the development of a complete model, able to fully describe the electromechanical properties of the IPMC materials, is the aim of many research groups. To that purpose this work focuses on designing and realising a system to determine the frequency domain behaviour of an IPMC strip as actuator in order to collect information useful to model it. Here the IPMC deformation, caused by applying a voltage input signal across its thickness, is detected by using an infrared transmitter-receiver couple. This methodology is largely diffused and it is based on the acquisition of the intensity of the emitted ray after being reflected by the moving target, moreover it constitutes a low cost solution. Also a transducer is used to acquire information about the current absorbed by the device under test. For the specific application a conditioning circuitry and the software for signal processing has been designed and realised. Preliminary results show that the proposed system allows to infer a number of interesting properties of IPMC based actuators.

Ionic polymer metal composites (IPMCs) are emerging materials used to realize motion sensors and actuators. In the former case by bending an IPMC membrane an electric signal is obtained, while in the latter case an electric input is able to cause the membrane to bend. Hence, it makes sense to investigate the opportunity to use IPMCs to build either actuators or sensors. Though a number of interesting properties have been described for such materials, few results have been obtained regarding their characterization. In this work, a new experimental setup to investigate IPMC behaviour as sensors is described and some results of the analysis of sensing properties of IPMCs strips are presented. In particular attention is focused on the influence of IPMC structure on the performance of the sensor and preliminary results concerning its life time are shows

Ionic polymer metal composites (IPMCs) are emerging materials used to realize motion sensors and actuators. In the former case by bending an IPMC membrane a voltage output is obtained, while in the latter case a voltage input is able to cause the membrane to bend. Although a number of interesting properties have been described for such materials, few results have been obtained regarding their characterization. In this paper a system devoted to the characterization of IPMCs as motion sensors is presented. The system was built in order to study the IPMC reaction, in a large range of frequencies, to a mechanical bending stimulus, in a cantilever configuration. An IPMC strip acts as the movable capacitive plate between two fixed plates, inside a differential capacitive measuring system. The motion of the IPMC is transduced into the system output voltage, without any mechanical contact, while ad-hoc electronics detect the IPMC sensing output voltage. A description of the IPMC characterization system follows a brief introduction to IPMC behaviour as sensors and actuators. Then, steps devoted to evaluation of the relationship between the input displacement forced to the IPMC being tested and the corresponding IPMC voltage output are derived.

Ionic Polymer Metal Composites (IPMCs) are innovative materials obtained by deposition of a metal on an ionic polymer membrane. IPMCs bend, when an electric field is applied along their thickness, and vice versa generate a voltage when they are mechanically deformed. Hence, it makes sense to investigate the opportunity to use IPMCs to build either actuators or sensors. IPMCs can be of interest because they need few volts to bend. Such an activation voltage is much lower than that required by other moving actuators (e.g. piezoelectric materials require hundreds of volts). In this work some results of the analysis of sensing properties of an IPMC strip are presented. Experimental data suggest that the output voltage is roughly linear in deformation. Moreover, a nonlinear behavior seems to occur under particular conditions. To our knowledge, such a behavior has not has been reported before in the literature.

The electron screening effect in the d(d, p)t reaction has been studied for several deuterated metals and insulators/semiconductors. As compared to measurements performed with a gaseous D2 target, a large effect has been observed in all metals except in the noble metals Cu, Ag, and Au. In contrast, a comparatively small effect is found for the insulators and semiconductors. An explanation of the large effect in metals is possibly provided by the classical plasma screening of Debye applied to the quasi-free metallic electrons.

To improve communication among caregivers about the status of patients under their care.Replacing manual white boards with electronic bed boards/inpatient databases, similar to airport display technology.Improved data quality from having patient data displayed in a standardized manner across care centers."We used a process redesign team, which focused on specific issues related to the processes used in providing patient care."

The 6Li$ + d$reactionwasstudiedinordertoinvestigatethequasi - free$6Li(n, $\displaystyle \alpha$ )3H$reaction, offtheprotonin$2H$.Akinematicallycompleteexperimentwasperformedatabeamenergyof14 MeV.Coincidencespectrashowthecontributionofthequasi - free$n + $6Li reaction in the relative energy range from 1.5MeV down to zero. The extracted 6Li(n,α)3H quasi-free cross-section was compared with the behavior of direct data throughout the investigated energy range. No penetrability corrections were introduced on the quasi-free data, being the 6Li(n,α)3H direct reaction free of Coulomb suppression.

Ionic polymer metal composites (IPMCs) belong to electroactive polymers (EAPs) and have been suggested for various applications due to their light weight and to the fact that they react mechanically when stimulated by an electrical signal and vice versa. Thick IPMCs (3D-IPMCs) have been fabricated by hot pressing several Nafion® 117 films. Additional post-processes (more cycles of Pt electroless plating and dispersing agents) have been applied to improve the 3D-IPMC performance. The electromechanical response of 3D-IPMCs has been examined by applying electrical signals and measuring the displacement and blocking force produced.

In this paper a novel force sensor, based on ionic polymer metal composites (IPMCs), is presented. The system has DC sensing capabilities and is able to work in the range of a few millinewtons. IPMCs are emerging materials used to realize motion actuators and sensors. An IPMC strip is activated in a beam fixed/simply-supported configuration. The beam is tightened at the simply-supported end by a force. This influences the natural resonant frequency of the beam; the value of the resonant frequency is used in the proposed system to estimate the force applied in the axial direction. The performance of the system based on the IPMC material has proved to be comparable with that of sensors based on other sensing mechanisms. This suggests the possibility of using this class of polymeric devices to realize PMEMS (plastic micro electrical mechanical systems) sensors.

The electrical behavior of an Ionic Polymer-Metal Composite (IPMC) is investigated. IPMCs are new materials of increasing interest in robotic applications, to implement artificial muscles. They are particularly light and they deform if electrically stimulated with a very low voltage. The paper illustrates a model that describes the electrical response of an IPMC as actuator by using an equivalent circuit. It is a totally new nonlinear lamped parameter model which is able to describe all the phenomena observed in the electrical current through the material, including hysteretic phenomena. The model has been validated by a large number of comparisons between simulations and experimental data. In all the cases analyzed the simulations agree with experimental data.

This work presents an innovative application of Ionic Polymer-Metal Composites (IPMC). The peculiarities and behavior of IPMC are examined and a dynamic model is proposed. Strips of these composites can undergo large bending displacement if an electric field is imposed across their thickness, thus they are motion actuators. More over, by bending the composite strips a voltage is produced across the thickness, obtaining motion sensors. The idea that inspired the work is the possibility of using IPMC to design autonomous structures able to move. Cellular Neural Networks (CNNs) have already demonstrated their powerfulness as new structures for bio-inspired locomotion generation and control. Here an approach to link the CNN capabilities to the availability of these new polymeric materials is presented. This strategy opens new and interesting applications in the field of autonomous and light structures able to self configure and move following spatial-temporal real time dynamics generated by CNNs.

OBJECTIVETo compare the epidemiology, clinical characteristics, and mortality of patients with bloodstream infections (BSI) caused by extended-spectrum β-lactamase (ESBL)-producing Escherichia coli (ESBL-EC) versus ESBL-producing Klebsiella pneumoniae (ESBL-KP) and to examine the differences in clinical characteristics and outcome between BSIs caused by isolates with CTX-M versus other ESBL genotypesMETHODSAs part of the INCREMENT project, 33 tertiary hospitals in 12 countries retrospectively collected data on adult patients diagnosed with ESBL-EC BSI or ESBL-KP BSI between 2004 and 2013. Risk factors for ESBL-EC versus ESBL-KP BSI and for 30-day mortality were examined by bivariate analysis followed by multivariable logistic regression.RESULTSThe study included 909 patients: 687 with ESBL-EC BSI and 222 with ESBL-KP BSI. ESBL genotype by polymerase chain reaction amplification of 286 isolates was available. ESBL-KP BSI was associated with intensive care unit admission, cardiovascular and neurological comorbidities, length of stay to bacteremia >14 days from admission, and a nonurinary source. Overall, 30-day mortality was significantly higher in patients with ESBL-KP BSI than ESBL-EC BSI (33.7% vs 17.4%; odds ratio, 1.64; P=.016). CTX-M was the most prevalent ESBL subtype identified (218 of 286 polymerase chain reaction-tested isolates, 76%). No differences in clinical characteristics or in mortality between CTX-M and non–CTX-M ESBLs were detected.CONCLUSIONSClinical characteristics and risk of mortality differ significantly between ESBL-EC and ESBL-KP BSI. Therefore, all ESBL-producing Enterobacteriaceae should not be considered a homogeneous group. No differences in outcomes between genotypes were detected.CLINICAL TRIALS IDENTIFIERClinicalTrials.gov. Identifier: NCT01764490.Infect Control Hosp Epidemiol 2018;39:660–667