On-the-go yield and sugar sensing in grape harvester

This paper summarises the results of a joint R+D project between university and industry. The study was developed at the Alt Penedès region, in Barcelona, during the 2006 and 2007 (on 3, 22, 69 fields respectively). The quality sensors set-up in year 2007, mounted on a New Holland SB55 grape harvester, were: two load cells, one refractometer, an ambient temperature prove and a GPS antenna, while in 2006 only the load cells and the GPS performed properly. The method used for this study is as follows: 1. Data recording from GPS and Logger (the latter is use for according and digitalising the sensor signal); 2. Wireless download of data to a PC; 3. Automatic data integration in a single file; 4. Lane automatic identification based on trajectory angles, machine forward speed determination, effective time calculation, masic flow, kg/m, and total amount harvested, kg/hopper, computation of characteristic soluble solid content and temperature during harvest; 5. Data broadcasting through GPRS to the winery; 6. Comparison of transmitted data with the invoice of the winery containers. After the season was finished, a data post processing was performed in order to a assess the causes of isolated incidences that were registered in 10 fields. Also a recalibration of the sensors for future seasons was performed. At current stage R 2 of 0.9547 is found between winery and in field yield data. Beside georeference data were gathered and compare to the remote photos in “Instituto Cartográfico de Cataluña”. Site-specific yield maps and speed maps have been computed while broad soluble solid information is not available due to slight dysfunctions of the grape juice pumping system towards to the refractometer

Hidden magnetic states emergent under electric field, in a room temperature composite magnetoelectric multiferroic

The ability to control a magnetic phase with an electric field is of great current interest for a variety of low power electronics in which the magnetic state is used either for information storage or logic operations. Over the past several years, there has been a considerable amount of research on pathways to control the direction of magnetization with an electric field. More recently, an alternative pathway involving the change of the magnetic state (ferromagnet to antiferromagnet) has been proposed. In this paper, we demonstrate electric field control of the Anomalous Hall Transport in a metamagnetic FeRh thin film, accompanying an antiferromagnet (AFM) to ferromagnet (FM) phase transition. This approach provides us with a pathway to "hide" or "reveal" a given ferromagnetic region at zero magnetic field. By converting the AFM phase into the FM phase, the stray field, and hence sensitivity to external fields, is decreased or eliminated. Using detailed structural analyses of FeRh films of varying crystalline quality and chemical order, we relate the direct nanoscale origins of this memory effect to site disorder as well as variations of the net magnetic anisotropy of FM nuclei. Our work opens pathways toward a new generation of antiferromagnetic - ferromagnetic interactions for spintronics

Full-bandwidth electrophysiology of seizures and epileptiform activity enabled by flexible graphene microtransistor depth neural probes

Mapping the entire frequency bandwidth of brain electrophysiological signals is of paramount importance for understanding physiological and pathological states. The ability to record simultaneously DC-shifts, infraslow oscillations (<0.1 Hz), typical local field potentials (0.1-80 Hz) and higher frequencies (80-600 Hz) using the same recording site would particularly benefit preclinical epilepsy research and could provide clinical biomarkers for improved seizure onset zone delineation. However, commonly used metal microelectrode technology suffers from instabilities that hamper the high fidelity of DC-coupled recordings, which are needed to access signals of very low frequency. In this study we used flexible graphene depth neural probes (gDNPs), consisting of a linear array of graphene microtransistors, to concurrently record DC-shifts and high-frequency neuronal activity in awake rodents. We show here that gDNPs can reliably record and map with high spatial resolution seizures, pre-ictal DC-shifts and seizure-associated spreading depolarizations together with higher frequencies through the cortical laminae to the hippocampus in a mouse model of chemically induced seizures. Moreover, we demonstrate the functionality of chronically implanted devices over 10 weeks by recording with high fidelity spontaneous spike-wave discharges and associated infraslow oscillations in a rat model of absence epilepsy. Altogether, our work highlights the suitability of this technology for in vivo electrophysiology research, and in particular epilepsy research, by allowing stable and chronic DC-coupled recordings

Haemodynamic effects of plasma-expansion with hyperoncotic albumin in cirrhotic patients with renal failure: a prospective interventional study

<p>Abstract</p> <p>Background</p> <p>Patients with advanced cirrhosis of the liver typically display circulatory disturbance. Haemodynamic management may be critical for avoiding and treating functional renal failure in such patients. This study investigated the effects of plasma expansion with hyperoncotic albumin solution and the role of static haemodynamic parameters in predicting volume responsiveness in patients with advanced cirrhosis.</p> <p>Methods</p> <p>Patients with advanced cirrhosis (Child B and C) of the liver receiving albumin substitution because of renal compromise were studied using trans-pulmonary thermodilution. Paired measurements before and after two infusions of 200 ml of 20% albumin per patient were recorded and standard haemodynamic parameters such as central venous pressure (CVP), mean arterial pressure (MAP), systemic vascular resistance index (SVRI), cardiac index (CI) and derived variables were assessed, including global end-diastolic blood volume index (GEDVI), a parameter that reflects central blood volume</p> <p>Results</p> <p>100 measurements in 50 patients (33 m/17 w; age 56 years (± 8); Child-Pugh-score 12 (± 2), serum creatinine 256 μmol (± 150) were analyzed. Baseline values suggested decreased central blood volumes GEDVI = 675 ml/m²(± 138) despite CVP within the normal range (11 mmHg (± 5). After infusion, GEDVI, CI and CVP increased (682 ml/m²(± 128) vs. 744 ml/m²(± 171), p < 0.001; 4.3 L/min/m²(± 1.1) vs. 4.7 L/min/m²(± 1.1), p < 0.001; 12 mmHg (± 6) vs. 14 mmHg (± 6), p < 0.001 respectively) and systemic vascular resistance decreased (1760 dyn s/cm⁵/m²(± 1144) vs. 1490 dyn s/cm⁵/m²(± 837); p < 0.001). Changes in GEDVI, but not CVP, correlated with changes in CI (r²= 0.51; p < 0.001). To assess the value of static haemodynamic parameters at baseline in predicting an increase in CI of 10%, receiver-operating-characteristic curves were constructed. The areas under the curve were 0.766 (p < 0.001) for SVRI, 0.723 (p < 0.001) for CI, 0.652 (p = 0.010) for CVP and 0.616 (p = 0.050) for GEDVI.</p> <p>Conclusion</p> <p>In a substantial proportion of patients with advanced cirrhosis, plasma expansion results in an increase in central blood volume. GEDVI but not CVP behaves as an indicator of cardiac preload, whereas high baseline SVRI is predictive of fluid responsiveness.</p

Enhanced magnetic properties in antiferromagnetic-core/ferrimagnetic-shell nanoparticles

Bi-magnetic core/shell nanoparticles are gaining increasing interest due to their foreseen applications. Inverse antiferromagnetic(AFM)/ferrimagnetic(FiM) core/shell nanoparticles are particularly appealing since they may overcome some of the limitations of conventional FiM/AFM systems. However, virtually no simulations exist on this type of morphology. Here we present systematic Metropolis Monte Carlo simulations of the exchange bias properties of such nanoparticles. The coercivity, H C, and loop shift, H ex, present a non-monotonic dependence with the core diameter and the shell thickness, in excellent agreement with the available experimental data. Additionally, we demonstrate novel unconventional behavior in FiM/AFM particles. Namely, while H C and H ex decrease upon increasing FiM thickness for small AFM cores (as expected), they show the opposite trend for large cores. This presents a counterintuitive FiM size dependence for large AFM cores that is attributed to the competition between core and shell contributions, which expands over a wider range of core diameters leading to non-vanishing H ex even for very large cores. Moreover, the results also hint different possible ways to enhance the experimental performance of inverse core/shell nanoparticles for diverse applications

PDMS-based, magnetically actuated variable optical attenuators obtained by soft lithography and inkjet printing technologies

This paper reports and compares the implementation of magnetic variable optical attenuators (M-VOA) by two fabrication strategies. In the first case, a two-layer structure containing a non-doped polydimethylsiloxane (PDMS) layer on a magnetic PDMS (M-PDMS) layer is fabricated by soft lithography (SLT). M-PDMS is obtained by doping PDMS with different ferrofluid (FF) volumes. The second technology consists of selectively dispense FF microdroplets using the inkjet printing technique (UP) on a non-doped, non-cured PDMS structure, previously defined by SLT. In this second case, FF volumes are encapsulated inside the polymer matrix. The optical and mechanical properties of structures fabricated using both strategies and containing similar ferrofluid amounts are compared. (C) 2014 Elsevier B.V. All rights reserved