Correlated random walks of human embryonic stem cells in vitro

We perform a detailed analysis of the migratory motion of human embryonic stem cells in two-dimensions, both when isolated and in close proximity to another cell, recorded with time-lapse microscopic imaging. We show that isolated cells tend to perform an unusual locally anisotropic walk, moving backwards and forwards along a preferred local direction correlated over a timescale of around 50 min and aligned with the axis of the cell elongation. Increasing elongation of the cell shape is associated with increased instantaneous migration speed. We also show that two cells in close proximity tend to move in the same direction, with the average separation of m or less and the correlation length of around 25 μm, a typical cell diameter. These results can be used as a basis for the mathematical modelling of the formation of clonal hESC colonies

Seeding hESCs to achieve optimal colony clonality

Human embryonic stem cells (hESCs) and induced pluripotent stem cells (iPSCs) have promising clinical applications which often rely on clonally-homogeneous cell populations. To achieve this, it is important to ensure that each colony originates from a single founding cell and to avoid subsequent merging of colonies during their growth. Clonal homogeneity can be obtained with low seeding densities; however, this leads to low yield and viability. It is therefore important to quantitatively assess how seeding density affects clonality loss so that experimental protocols can be optimised to meet the required standards. Here we develop a quantitative framework for modelling the growth of hESC colonies from a given seeding density based on stochastic exponential growth. This allows us to identify the timescales for colony merges and over which colony size no longer predicts the number of founding cells. We demonstrate the success of our model by applying it to our own experiments of hESC colony growth; while this is based on a particular experimental set-up, the model can be applied more generally to other cell lines and experimental conditions to predict these important timescales

OptEEmAL: Decision-Support Tool for the Design of Energy Retrofitting Projects at District Level

Designing energy retrofitting actions poses an elevated number of problems, as the definition of the baseline, selection of indicators to measure performance, modelling, setting objectives, etc. This is time-consuming and it can result in a number of inaccuracies, leading to inadequate decisions. While these problems are present at building level, they are multiplied at district level, where there are complex interactions to analyse, simulate and improve. OptEEmAL proposes a solution as a decision-support tool for the design of energy retrofitting projects at district level. Based on specific input data (IFC(s), CityGML, etc.), the platform will automatically simulate the baseline scenario and launch an optimisation process where a series of Energy Conservation Measures (ECMs) will be applied to this scenario. Its performance will be evaluated through a holistic set of indicators to obtain the best combination of ECMs that complies with user's objectives. A great reduction in time and higher accuracy in the models are experienced, since they are automatically created and checked. A subjective problem is transformed into a mathematical problem; it simplifies it and ensures a more robust decision-making. This paper will present a case where the platform has been tested.This research work has been partially funded by the European Commission though the European Union’s Horizon 2020 Research and Innovation Programme under grant agreement No 680676. All related information to the project is available at https://www.opteemal-project.eu

Outlier ensembles: A robust method for damage detection and unsupervised feature extraction from high-dimensional data

Outlier ensembles are shown to provide a robust method for damage detection and dimension reduction via a wholly unsupervised framework. Most interestingly, when utilised for feature extraction, the proposed heuristic defines features that enable near-equivalent classification performance (95.85%) when compared to the features found (in previous work) through supervised techniques (97.39%) — specifically, a genetic algorithm. This is significant for practical applications of structural health monitoring, where labelled data are rarely available during data mining. Ensemble analysis is applied to practical examples of problematic engineering data; two case studies are presented in this work. Case study I illustrates how outlier ensembles can be used to expose outliers hidden within a dataset. Case study II demonstrates how ensembles can be utilised as a tool for robust outlier analysis and feature extraction in a noisy, high-dimensional feature-space

Catalytic oxidation of emissions in combustion systems for forest biomass, using catalysts with TiO2 support

A study was made of the catalytic oxidation of a model mixture of effluents from forest biomass combustion equipment, consisting principally of methane (CH4), naphthalene (C10H8), carbon monoxide (CO) and oxygen-poor air (10% O2, balance N2), in a laboratory reactor, using MeOx/TiO2 catalysts (Me = Fe, Cu or Mn), prepared using incipient wetness impregnation. It was observed that the addition of metal oxides to the TiO2 increases catalytic activity in the combustion of all the contaminants present in the model effluent (CH 4, C10H8 and CO). The catalysts were characterised using the following techniques: SBET, XRD, DTG/DTA and TPD-NH 3; and from these it was observed that the support presented only the anatase phase in all the catalysts, despite having been subjected to temperatures in excess of 1.000 K during combustion. The highest acidity among all the solids tested, measured by TPD-NH3, was obtained for the FeOx/TiO2 catalysts, which were also those which showed the greatest catalytic activity. This high level of activity may be related to the formation of isolated metallic phases; i.e. hematite (Fe2O3), which would be the active phase in the combustion of C10H8 and CH4. On the other hand, with to respect to the 5 % wt. values of Me/TiO2 (Me: Fe, Cu y Mn) catalysts, the CuO/TiO2 catalyst shows greater activity than Fe2O3/TiO2 and MnOx/TiO2 for the oxidation of CO, which would be related to the formation of CuO on the TiO2 surface. The formation of mixed phases between the metals and the TiO2 was not observed. The SBET of the most active catalyst, Fe2O3/TiO2 (where Fe is 5% w/w in value), was not subject to any changes during the reaction

Isogeometric analysis of hyperelastic materials using petiGA

In this work different nonlinear hyperelastic models for slightly compressible materials are implemented in an isogeometric finite element model. This is done within the recently developed computational framework called PetIGA, which uses isogeometric analysis and modern computational tools to solve systems of equations directly and iteratively. A flexible theoretical background is described to implement other hyperelastic models and possibly transient problems in future work. Results show quadratic convergence of the nonlinear solution consistent with the Newton-Raphson method that was used. Finally, PetIGA proves to be a powerful and versatile tool to solve these types of problems efficiently. © 2013 The Authors. Published by Elsevier B.V

Cardiovascular-renal axis disorders in the domestic dog and cat: a veterinary consensus statement

OBJECTIVES There is a growing understanding of the complexity of interplay between renal and cardiovascular systems in both health and disease. The medical profession has adopted the term "cardiorenal syndrome" (CRS) to describe the pathophysiological relationship between the kidney and heart in disease. CRS has yet to be formally defined and described by the veterinary profession and its existence and importance in dogs and cats warrant investigation. The CRS Consensus Group, comprising nine veterinary cardiologists and seven nephrologists from Europe and North America, sought to achieve consensus around the definition, pathophysiology, diagnosis and management of dogs and cats with "cardiovascular-renal disorders" (CvRD). To this end, the Delphi formal methodology for defining/building consensus and defining guidelines was utilised. METHODS Following a literature review, 13 candidate statements regarding CvRD in dogs and cats were tested for consensus, using a modified Delphi method. As a new area of interest, well-designed studies, specific to CRS/CvRD, are lacking, particularly in dogs and cats. Hence, while scientific justification of all the recommendations was sought and used when available, recommendations were largely reliant on theory, expert opinion, small clinical studies and extrapolation from data derived from other species. RESULTS Of the 13 statements, 11 achieved consensus and 2 did not. The modified Delphi approach worked well to achieve consensus in an objective manner and to develop initial guidelines for CvRD. DISCUSSION The resultant manuscript describes consensus statements for the definition, classification, diagnosis and management strategies for veterinary patients with CvRD, with an emphasis on the pathological interplay between the two organ systems. By formulating consensus statements regarding CvRD in veterinary medicine, the authors hope to stimulate interest in and advancement of the understanding and management of CvRD in dogs and cats. The use of a formalised method for consensus and guideline development should be considered for other topics in veterinary medicine

Applicability of the shorter 'Bangladesh regimen' in high multidrug-resistant tuberculosis settings

In spite of the recent introduction of two new drugs (delamanid and bedaquiline) and a few repurposed compounds to treat multidrug-resistant and extensively drug-resistant tuberculosis (MDR- and XDR-TB), clinicians are facing increasing problems in designing effective regimens in severe cases. Recently a 9 to 12-month regimen (known as the 'Bangladesh regimen') proved to be effective in treating MDR-TB cases. It included an initial phase of 4 to 6 months of kanamycin, moxifloxacin, prothionamide, clofazimine, pyrazinamide, high-dose isoniazid, and ethambutol, followed by 5 months of moxifloxacin, clofazimine, pyrazinamide, and ethambutol. However, recent evidence from Europe and Latin America identified prevalences of resistance to the first-line drugs in this regimen (ethambutol and pyrazinamide) exceeding 60%, and of prothionamide exceeding 50%. Furthermore, the proportions of resistance to the two most important pillars of the regimen - quinolones and kanamycin - were higher than 40%. Overall, only 14 out of 348 adult patients (4.0%) were susceptible to all of the drugs composing the regimen, and were therefore potentially suitable for the 'shorter regimen'. A shorter, cheaper, and well-tolerated MDR-TB regimen is likely to impact the number of patients treated and improve adherence if prescribed to the right patients through the systematic use of rapid MTBDRsl testing

Reproductive and bloom patterns of Pelagia noctiluca in the Strait of Messina, Italy

Investigations on sexual reproduction of jellyfish are essential to understanding mechanisms and patterns of outbreaks formation. Pelagia noctiluca (Forskål, 1775) (Scyphozoa) is known as the predominant jellyfish species with direct development in Western and Central Mediterranean Sea. In this paper we used integrated morphometric, histological, and biochemical approaches to investigate the annual reproductive biology of P. noctiluca from the Strait of Messina (South Thyrrenian Sea), a key proliferation area for this species due to favourable temperatures and high productivity. From November 2011 to September 2012, P. noctiluca sexual reproduction occurred throughout the year, with two seasonal peaks (autumn, spring) of spawning and embryonic development. Gonads of female P. noctiluca were characterized by a large amount of mature eggs of small size (diameter < 200 mm) during high food availability, whereas fewer, larger eggs (diameter > 200 mm) were detected during low availability of prey. Two morphometric indexes were applied: the Gonad-Somatic Index (GSI, gonadal/somatic tissue dry weight ratio) and Fecundity Index (FI, n eggs mm2 * gonadal dry weight). The FI showed longer spawning periods than the GSI, providing a better causal-mechanistic explanation for the year-round occurrence of P. noctiluca in the Strait of Messina. Protein contents of the gonads changed seasonally, with the highest concentrations during the pre-spawning periods. We suggest that investigations on jellyfish sexual reproduction can provide biological information relevant for understanding mechanisms of jellyfish blooms as well as for the management of coastal zones affected by outbreaks of gelatinous species