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The aim of our study was to analyze circadian rhythm of the hematological profile of horses housed in a loose box and paddock during the different seasons (spring, summer, autumn, and winter). Blood samples were performed every 4 h for 48 consecutive hours. Red blood cells (RBCs), hemoglobin (HGB), hematocrit (HCT), white blood cells (WBCs), platelets (PLTs), and leukocyte subpopulations (neutrophils, basophils, eosinophils, lymphocytes, and monocytes) were analyzed, and, at the same time, environmental conditions were recorded. A statistically significant effect of housing conditions (p < 0.0001) was observed on all hematological values except for WBC during winter and for neutrophils (p < 0.0001) during spring and autumn. A statistically significant effect of season (p < 0.0001) was found for RBC, HCT, and PLT and for all leukocyte cells (p < 0.0001) except for basophils. The single Cosinor method revealed a daily rhythm of hematological parameters during spring in both groups, and a daily rhythm for lymphocytes and neutrophils was observed during spring and summer in horses kept in a loose box and during winter in horses housed in a paddock. Our results revealed that the response of the immune system is regulated by circadian physiology. Knowledge of the periodic temporal structure of mammals should be considered when evaluating animals’ adaptation to temporizations imposed by the environment.

Temperature monitoring is a major issue in induction motor drives, because temperature variations under working conditions may affect the machine lifetime and the control performance as well. The paper presents a technique for on-line monitoring the rotor and stator temperature on field-oriented induction motor drives, based on a new approach to estimate the rotor and stator winding resistances. The proposed approach exploits the injection of small additional current signals to extract the thermal status of the electrical machine, without affecting the normal drive operation. Moreover, it features a low computational effort, does not require other transducers than these already present in a standard field-oriented controlled drive and can be applied on both conventional and sensorless induction motor drives. The stator and rotor temperature estimation can be used either to prevent dangerous overheating and for on-line tuning of the control system. The practical effectiveness of the proposed approach is demonstrated by simulations and experimental tests.

A new approach to obtain an integrated battery charger is described in this paper, based on the Asymmetrical Hybrid Multilevel Converter topology. Such a particular open-end winding motor configuration, which has proved to be more efficient than conventional inverter topologies in EV motor drive applications, can be turned in an on-board battery charger only by acting on the control system. Thus, no circuit reconfiguration through electro-mechanical switches is required. Moreover, by introducing a single extra power switch, a bilateral power flow can be managed enabling vehicle to grid operations. The obtained integrated battery charger can be supplied either by a standard ac single-phase grid, either by a dc power source for direct connection to domestic energy resources. The proposed approach enables a new remarkable function to the asymmetrical hybrid multilevel converter at a marginal extra cost, thus mitigating the larger complexity and cost of such an inverter if compared with conventional topologies.

A new approach to compensate rotor position errors caused by parameter mismatching in model-based sensorless synchronous reluctance motor drives is presented in this paper. According to the proposed approach, the error in estimating the rotor position is detected by injecting some low-frequency current signals and adjusting the estimated rotor angular position through a gradient descent algorithm until minimizing the ripple generated on the estimated rotational speed. A rotor position correction can be fully on-line accomplished coping with saturation and cross saturation effects, as well as with unmodeled phenomena and unpredictable variations of the stator resistance with the temperature. The correction procedure can be accelerated by starting from an approximated correction table, which can be off-line built using the same technique. The proposed approach does not need additional current or voltage sensors, nor motor design modifications, thus providing an inexpensive mean to improve the control performance and robustness. Although originally conceived to deal with back-EMF based sensorless control techniques, the correction procedure can be extended to other model-based sensorless SynchRel motor drives.

Thermoregulation is an important mechanism to ensure thermal homeostasis. In horses, different housing conditions could influence this mechanism by exposing animals to different microclimates. The circadian rhythm of body temperature is well known. For this reason, we wanted to investigate the daily rhythm of cutaneous (jugular, shoulder, inner thigh and croup) temperature in comparison to rectal temperature in athletic horses kept under two different housing conditions. Ten clinically healthy Italian Saddle horses were divided into two equal groups: the first group was housed in individual boxes, and the second group was kept in paddocks. In all horses, rectal and cutaneous temperature measurements were performed every 4 h for 48 consecutive hours during different seasons (spring, summer, autumn and winter), respectively, by means of digital and infrared thermometers. Ambient temperature, relative humidity and ventilation were recorded simultaneously. A general linear model (GLM) was applied to the recorded temperature values displaying a significant effect of season, time of day, site of recording and housing condition (p 0.001). No statistical differences were found between the two days of monitoring (p = 0.49). A trigonometric statistical model (single cosinor method) was applied to investigate the circadian rhythm of rectal and cutaneous temperatures in the two different groups. Our results showed circadian rhythmicity of rectal temperature during all seasons and in both groups. Cutaneous temperature shows daily rhythmicity that was different in the various regions and was influenced by housing conditions and seasons. Application of GLM also showed a statistically significant effect of season and site of recording (p 0.0001) on all circadian parameters and of management condition on amplitude and robustness (p 0.0001). No statistical differences between the two days of monitoring were observed (p = 0.68). These findings are probably due to the animals' thermoregulatory mechanisms ensuring heat exchange between the body and the environment, and that was influenced by the microclimate. In particular, the microclimate influenced the thermodispersion disrupting the daily rhythmicity of some body regions, in horses kept in boxes. Only the temperate climatic conditions observed in summer guarantee the expression of the daily rhythmicity of all body surfaces in both management conditions. These results contribute to the knowledge of the mechanisms of homeostasis and control of body temperature in the athletic horse kept in different housing conditions, with a chronophysiological interpretation that completes the proper management of thermal well-being in horses.

Multiple-motor fed by multiple-converter systems feature a set of electric motor drives sharing the load through a common mechanical coupling. Such a coupling is exploited in this paper to build up a sensorless field oriented control, based on a quite common back-EMF technique to estimate the rotor flux angular position and an original approach to correct estimation errors. The technique is based on the injection of a suitable, very low frequency, sinusoidal signal on the current reference of one of the motor drives. If the estimated rotor flux position is correct, the drive output torque does not show variations. Differently, a torque ripple is generated at the frequency of the injected signal, whose effects on the system speed are easily compensated by the main speed controller. However, due to the mechanical coupling, an additional component of the reference torque current at the frequency of the injected signal is generated on all the other drives. By minimizing such a component, the estimated rotor flux position can be corrected online. The proposed method can also be exploited to estimate actual values of the stator resistance and of the rotor time constant.

A technique to improve the performance of grid-connected induction motors by exploiting an auxiliary winding set is proposed in this paper. This auxiliary winding features the same distribution of the main winding, although with a reduced number of turns and it is fed by an inverter a fraction of the power in comparison with the rated size of the induction motor. As shown in the paper, through the auxiliary winding, it is possible to set the machine power factor, increasing the efficiency of the power conversion system and mitigating speed oscillations due to torque disturbances. A mitigation of the grid current peaks due to motor start-up is obtainable. First, the proposed technique is theoretically introduced, then a feasibility assessment is accomplished by simulations.

Piezoelectric energy harvesters (PEHs) are a reduced, but fundamental, source of power for embedded, remote, and no-grid connected electrical systems. Some key limits, such as low power density, poor conversion efficiency, high internal impedance, and AC output, can be partially overcome by matching their internal electrical impedance to that of the applied resistance load. However, the applied resistance load can vary significantly in time, since it depends on the vibration frequency and the working temperature. Hence, a real-time tracking of the applied impedance load should be done to always harvest the maximum energy from the PEH. This paper faces the above problem by presenting an active control able to track and follow in time the optimal working point of a PEH. It exploits a non-conventional AC–DC converter, which integrates a single-stage DC–DC Zeta converter and a full-bridge active rectifier, controlled by a dedicated algorithm based on pulse-width modulation (PWM) with maximum power point tracking (MPPT). A prototype of the proposed converter, based on discrete components, was created and experimentally tested by applying a sudden variation of the resistance load, aimed to emulate a change in the excitation frequency from 30 to 70 Hz and a change in the operating temperature from 25 to 50 °C. Results showed the effectiveness of the proposed approach, which allowed to match the optimal load after 0.38 s for a ΔR of 47 kΩ and after 0.15 s for a ΔR of 18 kΩ.

An optimal current control strategy for asymmetrical hybrid multilevel inverters (MLIs) is proposed in this paper enabling their use on motor drives, static synchronous compensators, and photovoltaic and wind generators, where a fast and precise current regulation is required. A key feature of these highly efficient converters is that an ac machine (motor or transformer) operates according to an open-end winding configuration, connected on one side to a main MLI and, on the other side, to an auxiliary two-level inverter (TLI). The first efficiently controls the main power stream operating at a low switching frequency, while the TLI acts as an active power filter, exploiting a conventional high-frequency two-level pulsewidth modulation (PWM) technique. The proposed control scheme optimally exploits the key features of the two inverters by suitably sharing the control task. In fact, a predictive current control is assigned to the MLI, which can be accomplished by low switching frequency operations, while the high switching frequency of the PWM-operated TLI is exploited to accomplish a fast and precise closed-loop current control, processing only a part of the power stream flowing through the system, thus producing low power losses. Simulations and experimental results confirm the consistency of the proposed approach.

An open-end winding machine configuration and a suitable control strategy for medium-voltage ac motor drives applications are proposed in this paper in order to reduce the distortion of phase voltages in multilevel inverters (MLIs). Differently than standard open-end winding configurations, where two inverters provide active power to both sides of the stator winding, a main MLI supplies in this case the machine on one side, while an auxiliary two-level inverter acts as active power filter on the other side. A high efficiency step modulation manages the MLI, while the auxiliary unit is pulse width modulation (PWM) operated. As the phase current harmonic content is improved, the torque ripple is reduced and the drive efficiency is increased. By exploiting the proposed approach, the apparent switching frequency of the system is that typical of a PWM inverter, although the main unit is operated according to a voltage step modulation strategy. Simulation and experimental results confirm the consistency of the proposed methodology.

Magnetic skyrmions are emerging as key elements of unconventional operations having unique properties such as small size and low current manipulation. In particular, it is possible to design skyrmion based neurons and synapses for neuromorphic computing in devices where skyrmions move along the current direction (zero skyrmion Hall angle). Here, we show that, for a given graph, skyrmions can be used in optimization problems facing the calculation of the shortest path. Our tests show a solution with the same path length as computed with the Dijkstra’s Algorithm. In addition, we also discuss how skyrmions act as positive feedback on this type of problems giving rise to a self-reinforcement of the path which is a possible solution.

Gluten proteins are the causative agent of Celiac Disease (CD), a life-long food intolerance characterized by an autoimmune enteropathy. Inadvertent gluten exposure is frequent even in celiac patients complying with a gluten-free diet, and the supplementation of exogenous gluten-digestive enzymes (glutenases) is indeed a promising approach to reduce the risk of dietary gluten boost. Here we describe Endopeptidase 40, a novel glutenase discovered as secreted protein from the soil actinomycete Actinoallomurus A8, and its recombinant active form produced by Streptomyces lividans TK24. E40 is resistant to pepsin and trypsin, and active in the acidic pH range 3 to 6. E40 efficiently degrades the most immunogenic 33-mer as well as the whole gliadin proteins, as demonstrated by SDS-PAGE, HPLC, LC-MS/MS, and ELISA. T lymphocytes from duodenal biopsies of celiac patients showed a strongly reduced or absent release of IFN-γ when exposed to gluten digested with E40. Data in gastrointestinal simulated conditions suggest that no toxic peptides are freed during gluten digestion by E40 into the stomach to enter the small intestine, thus counteracting the intestinal inflammatory cascade to occur in CD patients. E40 is proposed as a novel candidate in Oral Enzymatic Therapy for the dietary management of gluten toxicity.

Poly (Lactic Acid), PLA, and Poly (&epsilon, CaproLactone), PCL, compatibilized with Ethyl Ester l-Lysine Triisocyanate (LTI) can be employed as biomaterials. We mixed PLA with PCL and LTI in a twin extruder and by a melt spinning process obtained threads with an average diameter of about 0.3 mm. In order to study the possible application of these threads, mechanical tensile (with the calorimetric and morphological investigations) and biological tests were performed. The results highlighted these biopolymers as promising materials for sutures since they can be rigid and elastic (especially by increasing the PCL amount in the blend), and they are bioactive, able to inhibit bacterial growth. This paper represents a starting point to optimize the blend composition for biomedical suture application.

A three-phase multi-level multi-input power converter topology is presented for grid-connected applications. It encompasses a three-phase transformer that is operated on the primary side in an open-end winding configuration. Thus, the primary winding is supplied on one side by a three-phase N-level neutral point clamped inverter and, on the other side, by an auxiliary two-level inverter. A key feature of the proposed approach is that the N-level inverter is able to perform independent management of N − 1 input power sources, thus avoiding the need for additional dc/dc power converters in hybrid multi-source systems. Moreover, it can manage an energy storage system connected to the dc-bus of the two-level inverter. The N-level inverter operates at a low switching frequency and can be equipped with very low on-state voltage drop Insulated-Gate Bipolar Transistor (IGBT) devices, while the auxiliary inverter is instead operated at low voltage according to a conventional high-frequency two-level Pulse Width Modulation (PWM) technique and can be equipped with very low on-state resistance Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET) devices. Simulations and experimental results confirm the effectiveness of the proposed approach and its good performance in terms of grid current harmonic content and overall efficiency.

Wheat (Triticum spp. L.), rye (Secale cereal L.), and barley (Hordeum vulgare L.) seeds contain peptides toxic to celiac patients. Maize (Zea mays L.) and rice (Oryza sativa L.) are distant relatives of wheat as well as sorghum (Sorghum bicolor (L.) Moench) and are known to be safe for celiacs. Both immunochemical studies and in vitro and in vivo challenge of wheat-free sorghum food products support this conclusion, although molecular evidence is missing. The goal of the present study was to provide biochemical and genetic evidence that sorghum is safe for celiac patients. In silico analysis of the recently published sorghum genome predicts that sorghum does not contain peptides that are toxic for celiac patients. Aqueous/alcohol-soluble prolamins (kafirins) from different sorghum varieties, including pure lines and hybrids, were evaluated by SDS-PAGE and HPLC analyses as well as an established enzyme-linked immunosorbent assay (ELISA) based on the R5 antibody. These analyses provide molecular evidence for the absence of toxic gliadin-like peptides in sorghum, confirming that sorghum can be definitively considered safe for consumption by people with celiac disease.

We have established primary cell culture of the marine demosponge Dysidea avara and Suberites domuncula . Microbial contamination was controlled by the use of a pool of antibiotics confirming the goodness of this procedure. Effect of pH, temperature and light was studied to establish the better growth conditions. The comparison of lipid composition of sponge and cells suggested a series of experiments to optimise the medium. A glucose dose-dependent experiment showed that the ideal glucose concentration is 1 g l −1 . Supplementing the medium with unsaturated fatty acid and retinol, no promotion of growth was observed, but the compounds were totally metabolised by cells. Increments from 70 to 160% in the number of cells were observed, supplementing the medium with different concentration of cholesterol. These results suggest that the analysis of the chemical composition of sponge and cells give indication on the composition of the nutrient media.

Some of DC actuators used in home automation, office automation, medical equipment and automotive systems require a position sensor. In low power applications, the introduction of such a transducer remarkably increases the whole system cost, which justifies the development of sensorless position estimation techniques. The well-known AC motor drive sensorless techniques exploiting the fundamental component of the back electromotive force cannot be used on DC motor drives. In addition, the sophisticated approaches based on current or voltage signal injection cannot be used. Therefore, an effective and inexpensive sensorless position estimation technique suitable for DC motors is presented in this paper. This technique exploits the periodic pulses of the armature current caused by commutation. It is based on a simple pulse counting algorithm, suitable for coping with the rather large variability of the pulse frequency and it leads to the realization of a sensorless position control system for low cost, medium performance systems, like those in the field of automotive applications.

Modified space-vector modulations (MSVMs) that reduce the variations of common mode voltage (CMV) for decreasing common mode currents (CMCs) are a low cost interesting approach. Unfortunately the lack of full utilisation of the DC bus voltage is a severe drawback that can limit the exploitation of such modulation techniques, unless special overmodulation methods are adopted. In this study, some solutions are presented that make a trade-off between the DC bus voltage exploitation and CMCs reduction and make MSVMs appealing to most electrical drives on the market. Furthermore, the influence of dead time in CMV generation is considered thus modifying the switching patterns according to the sign of the load currents. Experimental results are presented in order to confirm the feasibility of the proposed approach.

Proteomic techniques were applied for the investigation of “avenin-like protein type-B” in tetraploid wheat. Protein was extracted from endosperm, according to a classical chromatographic procedure and its identity confirmed by liquid chromatography-tandem mass spectrometry analysis. The characterization of avenin-like protein type-B was in good agreement with the gene-derived sequence, with the exception of glutamine as N-terminus. The presence in the glutenin extract and the high number of cysteine residues suggested that avenin-like protein type-B is integrated into gluten polymers via inter-chain disulphide bonds. This raises the question of whether the protein could play a role in determining the functional properties of gluten.

Fuel cell stacks represent a quite promising technology for the realization of small electrical generators for distributed generation. Key advantages of fuel cells over combustion based generators are the absence of polluting emissions and a high efficiency even on small size systems and partial loads. A typical application of distributed generators is in the residential field, where they are connected to single phase AC grids. In these cases a power unbalance is generated because the power drawn by the grid features a large ripple at twice the fundamental frequency, while the power produced by the stack is essentially constant. A large capacitor bank is then used to solve such a power unbalance, that however causes a ripple on the stack output current. This ripple is shortens the fuel cell lifetime, to worsen the stack efficiency and to reduce the available peak power. Active current ripple reduction techniques have been proposed in the past exploiting expensive active filters. An alternative approach is proposed in this paper where an active filter is integrated into the converter, without introducing extra power devices. Moreover, the auxiliary power supply is integrated in the main converter partially compensating the power unbalance. According to the proposed approach the size of the electrolytic capacitor bank can be largely reduced, thus improving the reliability, while lowering costs and size.

One of the main objectives of wheat glutenin subunit (GS) analysis is the identification of protein components linked to wheat quality. The proteomic characterization of glutenin has to consider the relatively low levels of arginine and lysine residues and the close sequence similarity among the different groups of these subunits, which hinders or even prevents the identification of the GS. In this study, a proteomic approach has been applied to resolve the heterogeneity of wheat glutenin components. Proteins extracted from Triticum durum flour were first analyzed by two-dimensional gel electrophoresis, which greatly reduced glutenin complexity. The identity of each spot was confirmed by nano liquid chromatography tandem mass spectrometry analysis of tryptic peptides. In parallel, measurements of the high mass range by matrix-assisted laser desorption/ionization time-of-flight analysis allowed detection of the large tryptic peptides. Gathering all data from search engine interrogation, very high sequence coverage was obtained for high molecular weight GS, including Bx7 and By8, in agreement with the known genetic profile of durum wheat. In addition, a truncated form of By8, never detected before, was also found. Low molecular weight GS (LMW-GS) B-type was identified with reasonable sequence coverage, while a clear identification of LWM-GS C- and D-type was hindered by the incompleteness of the wheat DNA databases. This study represents the first comprehensive analysis of the glutenin proteome and provides a reliable method for classifying wheat varieties according to their glutenin profile.