Performance of an Adaptive Controller for the Neuromuscular Blockade Based on Inversion of a Wiener Model

An adaptive controller based on a minimally parameterized parsimonious Wiener model for the effect of the muscle relaxant rocuronium in the neuromuscular blockade is presented. The controller structure combines inversion of the recursively identified static nonlinearity of the Wiener model with a positive compartmental control law for the linearized system. The overall strategy exploits the fact that the model has only two parameters, which are estimated by an extended Kalman filter. Due to the fact that the positive control law for total mass conservation of compartmental systems is only proven to be convergent for time‐invariant systems, the identification of the parameter in the linear block of the minimally parameterized parsimonious Wiener model is stopped when the controller is turned on. The controller was implemented in the platform Galeno and tested in simulation and in thirteen real cases of patients under general anesthesia. The good reference tracking results and robustness to noise show the reliability of the proposed strategy.     

Practices and risks associated with operation of tie-down lashings in the vehicle transport industry

Load restraint systems in automobile transport utilise tie-down lashings placed over the car’s tyres, which are tensioned manually by the operator using a ratchet assembly. This process has been identified as a significant manual handling injury risk. The aim of this study was to gain insight on the current practices associated with tie-down lashings operation, and identify the gaps between current and optimal practice. We approached this with qualitative and quantitative assessments and one numerical simulation to establish: (i) insight into the factors involved in ratcheting; (ii) the required tension to hold the car on the trailer; and (iii) the tension achieved by drivers in practice and associated joint loads. We identified that the method recommended to the drivers was not used in practice. Drivers instead tensioned the straps to the maximum of their capability, leading to over-tensioning and mechanical overload at the shoulder and elbow. We identified the postures and strategies that resulted in the lowest loads on the upper body during ratcheting (using both hands and performing the task with their full body). This research marks the first step towards the development of a training programme aiming at changing practice to reduce injury risks associated with the operation of tie-down lashings in the automobile transport industry.

Practitioner Summary: The study investigated current practice associated with the operation of tie-down lashings through qualitative (interviews) and quantitative (biomechanical analysis) methods. Operators tended to systematically over-tension the lashings and consequently overexert, increasing injury risks.     

Viscous Open Data: The Roles of Intermediaries in an Open Data Ecosystem

Open data have the potential to improve the governance of universities as public institutions. In addition, open data are likely to increase the quality, efficacy and efficiency of the research and analysis of higher education systems by providing a shared empirical base for critical interrogation and reinterpretation. Drawing on research conducted by the Emerging Impacts of Open Data in Developing Countries project, and using an ecosystems approach, this research paper considers the supply, demand and use of open data as well as the roles of intermediaries in the governance of South African public higher education. It shows that government's higher education database is a closed and isolated data source in the data ecosystem; and that the open data that are made available by government is inaccessible and rarely used. In contrast, government data made available by data intermediaries in the ecosystem are being used by key stakeholders. Intermediaries are found to play several important roles in the ecosystem: (i) they increase the accessibility and utility of data; (ii) they may assume the role of a “keystone species” in a data ecosystem; and (iii) they have the potential to democratize the impacts and use of open data. The article concludes that despite poor data provision by government, the public university governance open data ecosystem has evolved because intermediaries in the ecosystem have reduced the viscosity of government data. Further increasing the fluidity of government open data will improve access and ensure the sustainability of open data supply in the ecosystem.     

Adaptive observer design for discrete time LTV systems

In this paper, the discrete-time exponential forgetting factor observer is specialised for the joint estimation of state and parameters, leading to an adaptive observer in which the decay rates of the estimation errors for the two distinct objects can be quasi-separated. The effectiveness of the observer is demonstrated through numerical simulation.     

Al2O3-ZrO2 Finely Structured Multilayer Architectures from Suspension Plasma Spraying

Suspension plasma spraying (SPS) is an alternative to conventional atmospheric plasma spraying (APS) aiming at manufacturing thinner layers (i.e., 10-100 μm) due to the specific size of the feedstock particles, from a few tens of nanometers to a few micrometers. The staking of lamellae and particles, which present a diameter ranging from 0.1 to 2.0 μm and an average thickness from 20 to 300 nm, permits to manufacture finely structured layers. Moreover, it appears as a versatile process able to manufacture different coating architectures according to the operating parameters (suspension properties, injection configuration, plasma properties, spray distance, torch scan velocity, scanning step, etc.). However, the different parameters controlling the properties of the coating, and their interdependences, are not yet fully identified. Thus, the aim of this paper is, on the one hand, to better understand the influence of operating parameters on the coating manufacturing mechanisms (in particular, the plasma gas mixture effect) and, on the other hand, to produce Al₂O₃-ZrO₂ finely structured layers with large varieties of architectures. For this purpose, a simple theoretical model was used to describe the plasma torch operating conditions at the nozzle exit, based on experimental data (mass enthalpy, arc current intensity, thermophysical properties of plasma forming gases, etc.) and the influences of the spray parameters were determined by mean of the study of sizes and shapes of spray beads. The results enabled then to reach a better understanding of involved phenomena and their interactions on the final coating architectures permitting to manufacture several types of microstructures.     

High prevalence of antimicrobial‐resistant Escherichia coli from animals at slaughter: a food safety risk

BACKGROUND: There has been concern about the increase of antimicrobial resistant bacteria and protection of animal and public health, along with food safety. In the present study, we evaluate the incidence of antimicrobial resistance among 192 strains of Escherichia coli isolated from faecal samples of healthy food‐producing animals at slaughter in Portugal. RESULTS: Ninety‐seven % of the pig isolates, 74% from sheep and 55% from cattle were resistant to one or more antimicrobial agents, with the resistances to ampicillin, streptomycin, tetracycline and trimethoprim–sulfamethoxazole the most common phenotype detected. Genes encoding resistance to antimicrobial agents were detected in most of the resistant isolates. Ninety‐three % of the resistant isolates were included in the A or B1 phylogenetic groups, and the virulence gene fimA (alone or in association with papC or aer genes) was detected in 137 of the resistant isolates. Five isolates from pigs belonging to phylogroup B2 and D were resistant to five different antimicrobial agents. CONCLUSION: Our data shows a high percentage of antibiotic resistance in E. coli isolates from food animals, and raises important questions in the potential impact of antibiotic use in animals and the possible transmission of resistant bacteria to humans through the food chain. © 2012 Society of Chemical Industry     

Phenols,Flavonoids, and Antioxidant and Antibacterial Activity of Leaves and Stem Bark of Morus Species

Leaves and stem bark composition from Morus species (M. alba var. alba, M. alba var. rosa and M. rubra) was evaluated for its antioxidant and antimicrobial activities in order to enhance its therapeutic uses. Total phenolics and flavonoids contents were estimated in hydromethanolic and aqueous extracts. Results showed highest content in M. rubra leaves aqueous extract (1129 mg gallic acid equivalent/100 g dry weight and 816 mg gallic acid equivalent/100 g dry weight, respectively). Using 2,2-diphenyl-1-picrylhydrazyl assay, the highest antioxidant activity was obtained in aqueous stem barks extracts. M. alba var. alba has an IC₅₀ of 2.84 mg/ml and the IC₅₀ value of M. rubra was the highest (4.78 mg/ml). ABTS^.+ (2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid)) method and reducing power assay were used to confirm the results from the 2,2-diphenyl-1-picrylhydrazyl test. All extracts expressed considerable free radical-scavenging properties. Hydromethanolic and aqueous extracts were tested against Staphylococcus aureus, Enterococcus feacalis, Staphylococcus epidermis, Escherichia coli, and Salmonella Typhimurium bacteria. Hydromethanolic stem bark extracts have the highest antimicrobial activities, and it may be a good antimicrobial agent for human gastrointestinal infections. This plant could be used as an additive to foods and also as a possible source to obtain new and effective herbal medicines to treat infections of multi-drug resistant strains of microorganisms.     

Non-destructive evaluation of ripening and quality traits in apples using a multiparametric fluorescence sensor

BACKGROUND: The detection of pigments and colourless flavonoids in apples can provide a useful indication of fruit quality. Optical methods are preferable because they are fast and non‐destructive. In this study, a fluorescence‐based portable sensor was used in order to non‐invasively determine the content of chlorophylls, anthocyanins and flavonols in Fuji, Granny Smith and Golden Delicious apple cultivars. The aim was to define new non‐destructive optical indices of apple quality. RESULTS: The anthocyanin index (ANTH) in Fuji was higher in the sunny (i.e. sun‐exposed) side of the fruit compared to the shady side. For all cultivars, the flavonol index (FLAV) was higher in the sunny side compared with the shady side. The chlorophyll index (CHL) for the shady sides of Granny Smith and Golden Delicious was significantly higher than for the sunny sides. Fine linear regressions were found between the ANTH, FLAV and CHL indices and the actual anthocyanin, flavonol and chlorophyll concentrations, respectively, which were determined destructively on the apple peel extracts. A negative correlation was found between the apple sugar content and the chlorophyll fluorescence in the far‐red spectral band. CONCLUSION: Our results indicate that a single multiparametric fluorescence‐based sensor can provide valuable non‐destructive markers of ripening and quality in apples. Copyright © 2012 Society of Chemical Industry     

Hematological and biochemical parameters of dairy calves submitted to pegbovigrastim administration

This study was designed to evaluate the response of hematological and biochemical parameters submitted to pegbovigrastim administration and postchallenge with lipopolysaccharide (LPS). In experiment 1, 20 newborn Holstein calves were divided into 2 groups: the Imrestor (Elanco Saúde Animal, São Paulo, Brazil) group (IMR, n = 10), which received a 25 μg/kg of body weight (BW) subcutaneous administration of pegbovigrastim, and the control group (CTR, n = 10), which received a subcutaneous administration of 0.9% saline solution. Blood samples were collected on d 0, 10, 12, and 14 relative to birth to analyze the biochemical and hematological parameters. Moreover, growth measurements were taken on d 0, 7, 14, 21, and 60 relative to birth. The number of total leukocytes in the IMR group increased on d 12 and 14 in comparison to the CTR group, as well as the counts of segmented neutrophils, band cells, and monocytes. No differences were observed in the other hematological, biochemical, and growth parameters. In experiment 2, 20 Holstein calves from 30 to 60 d old were divided into 4 groups: group 1 (LPS, n = 5) received a 0.25 μg/kg of BW single intravenous dose of Escherichia coli LPS at d 0; group 2 (IMR, n = 5) received a 25 μg/kg of BW subcutaneous dose of pegbovigrastim at d 1; group 3 (IMR + LPS, n = 5) received a 0.25 μg/kg of BW intravenous LPS dose at d 0 and a 25 μg/kg of BW subcutaneous dose of pegbovigrastim at d 1; and group 4 (CTR, n = 5) received an intravenous dose of 0.9% sodium chloride at d 0 and a subcutaneous dose of 0.9% sodium chloride at d 1. For the analysis of biochemical and hematological parameters, blood samples were collected on d ?1, 0, 1, 2, 3, 4, 8, 14, and 21 relative to LPS administration. An increase in the number of total leukocytes was observed in the IMR, IMR + LPS, and LPS groups, and the IMR group remained as the highest from d 2 to 21. The levels of paraoxonase 1 were higher in the IMR group compared with all the others. The administration of pegbovigrastim in the dairy calves increased the number of circulating leukocytes, especially neutrophils, with an increase in paraoxonase 1, without altering the metabolites for the hepatic function.     

Combined speciation analysis by X-ray absorption near-edge structure spectroscopy, ion chromatography, and solid-phase microextraction gas chromatography-mass spectrometry to evaluate biotreatment of concentrated selenium wastewaters

In this study we evaluate the potential of anaerobic granular sludge as an inoculum for the bioremediation of selenium-contaminated waters using species-specific analytical methods. Solid species formed by microbial reduction were investigated using X-ray absorption near-edge structure (XANES) spectroscopy at the selenium K-edge. Furthermore, dissolved selenium species were specifically determined by ion chromatography (IC) and solid-phase microextraction gas chromatography-mass spectrometry (SPME-GC-MS). Least-squares linear combination of the XANES spectra for samples incubated with the highest selenate/selenite concentrations (10(-3) M) show the predominance of elemental selenium and a Se(-I) selenide, such as ferroselite, the thermodynamically most stable iron selenide. In contrast, elemental selenium and Se(-II) selenides are the main species detected at the lower selenate/selenite concentrations. In each repeated fed batch incubation, most aqueous selenite anions were converted into solid selenium species, regardless of the type of electron donor used (acetate or H(2)/CO(2)) and the selenium concentration applied. On the other hand, at higher concentrations of selenate (10(-4) and 10(-3) M), significant amounts of the oxyanion remained unconverted after consecutive incubations. SPME-GC-MS demonstrated selenium alkylation with both electron donors investigated, as dimethyl selenide (DMSe) and dimethyl diselenide (DMDSe). Selenite was even more alkylated in the presence of H(2)/CO(2) (maximum 2156 μg of Se/L of DMSe + DMDSe) as compared to acetate (maximum 50 μg of Se/L). In contrast, selenate was less alkylated using both electron donors (maximum 166 and 3 μg of Se/L, respectively). The high alkylation potential for selenite limits its bioremediation in selenium laden waters involving H(2)/CO(2) as the electron donor despite the fact that nontoxic elemental selenium and thermodynamically stable metal selenide species are formed.