Ecological effects of cellular computing in microbial populations

Gene regulatory networks allow single cells to adopt a wide range of different phenotypes in response to changes in environmental conditions. The ecological implications of these cellular computations are poorly understood, and they are largely absent from models of microbial community assembly. Here, we highlight a number of examples where ecological interactions are or may be affected by cellular computations. Our review identifies specific opportunities for integrating cellular decision-making into mathematical models of microbe-microbe interactions and community assembly. We argue that incorporating cellular decision-making into microbial ecology will be critical in order to gain a quantitative understanding of microbial biogeography.     

Metals migration between product and metallic package in canned meat

The aim of this study is to investigate the migration of heavy metals in meat can under different parameters (varnish, storage time, storage temperature, storage humidity and varnish width and porosity). The physicochemical and organoleptic properties of the meat can have been analyzed. The metal content (Cd, Pb, Cu, Fe, Zn and Sn) were determined by flame and graphite furnace atomic absorption spectrometry after microwave digestion. The organoleptic and physicochemical properties of the samples have not modified significantly during the experiments. The metals migration is not influenced significantly by the varnish type. The highest level of metals in food products was observed at 4 and 50 °C. The porosity influenced significantly (p < 0.05) the migration of metals while the varnish width influence is not a significant one. The migration modeling using 3rd grade polynomial model achieved models with high coefficients of regression (greater than 0.9858).     

A Review of Cell Adhesion Studies for Biomedical and Biological Applications

Cell adhesion is essential in cell communication and regulation, and is of fundamental importance in the development and maintenance of tissues. The mechanical interactions between a cell and its extracellular matrix (ECM) can influence and control cell behavior and function. The essential function of cell adhesion has created tremendous interests in developing methods for measuring and studying cell adhesion properties. The study of cell adhesion could be categorized into cell adhesion attachment and detachment events. The study of cell adhesion has been widely explored via both events for many important purposes in cellular biology, biomedical, and engineering fields. Cell adhesion attachment and detachment events could be further grouped into the cell population and single cell approach. Various techniques to measure cell adhesion have been applied to many fields of study in order to gain understanding of cell signaling pathways, biomaterial studies for implantable sensors, artificial bone and tooth replacement, the development of tissue-on-a-chip and organ-on-a-chip in tissue engineering, the effects of biochemical treatments and environmental stimuli to the cell adhesion, the potential of drug treatments, cancer metastasis study, and the determination of the adhesion properties of normal and cancerous cells. This review discussed the overview of the available methods to study cell adhesion through attachment and detachment events.     

Multiresidue determination of antibiotics in feed and fish samples for food safety evaluation. Comparison of immunoassay vs LC-MS-MS

Antibiotic residues (sulfonamides and tetracyclines) were determined in Gilthead sea bream (Sparus aurata) and feed samples by means of immunoassays and LC-MS-MS (liquid chromatography-mass spectrometry²). A preliminary study to know the withdrawal time of oxytetracycline in Gilthead sea bream samples was also conducted. It was carried out using immunoassays based on photometric detection of horseradish peroxidase (HRP) activity and time-resolved fluorometric detection of coproporphyrin of Platinum (II) (ELISA and TR-FIA, respectively). The results were compared to those obtained using an LC-MS-MS methodology. They showed that approximately 37 days would be the withdrawal time in order not to exceed the MRL and fish could be commercialized with safety.Regarding feed samples analysis, an LC-MS-MS method was optimized including sample treatment. Average recoveries (n = 6) ranging from 78 to 108% were obtained and precision of the method was between 0.2 and 3%. The same sample treatment was applied to the feed immunoanalysis obtaining satisfactory results.Finally, 20 fish and 4 feed samples were analysed in order to confirm the feasibility of the immunoassays for detecting antibiotic residues. Sulfonamide residues were not detected in any fish sample. Tetracycline residues were detected in some fish samples from marine farms, with total concentrations between 2.1 and 152 ng g^?1. In all cases, the obtained results correlated well with those achieved by LC-MS-MS. Therefore, the new methodology allows for food safety of the medicated fish.     

Detection of Ring and Adatom Defects in Activated Disordered Carbon via Fluctuation Nanobeam Electron Diffraction

How the structure of disordered porous carbons evolves during their activation is particularly poorly understood. This problem endures primarily because of a lack of high‐resolution 3D techniques for the characterization of amorphous and highly disordered structure. To address this, the measurement of the 3D pair‐angle distribution function using nanodiffraction patterns from high‐energy electrons is demonstrated. These rich multiatom correlations are measured for a disordered carbon and they clearly show the structural evolution during activation. They provide previously inaccessible bond‐angle information and direct evidence for the presence of ring and adatom defects. An increase in the short‐range order and the number of fivefold ring defects with activation are observed, indicating stress relaxation by increasing curvature. These observations support models of disordered porous carbons based on curved graphene networks and explain how large amounts of free volume can be created with surprisingly small changes in the average ratios of tetrahedral to graphitic bonding.     

Working with conflict in clinical supervision: Wise supervisors' perspectives.

Eight female and 4 male supervisors identified by professional peers as highly competent were interviewed about experiences of conflict in supervision and their dependable strategies for managing it. Highly competent supervisors were open to conflict and interpersonal processing, willing to acknowledge shortcomings, developmentally oriented, and willing to learn from mistakes. They believed in creating strong supervisory alliances, discussing evaluation early on, modeling openness to conflict, and providing timely feedback. Dependable strategies included contextualizing conflicts in light of developmental and environmental factors, seeking consultation with colleagues, self-coaching, processing conflicts, accentuating supervisee strengths, interpreting parallel processes, and withdrawing from supervisee dynamics. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Estimating Volumes of Near-Spherical Molded Artifacts

The Food and Drug Administration (FDA) is conducting research on developing reference lung cancer lesions, called phantoms, to test computed tomography (CT) scanners and their software. FDA loaned two semi-spherical phantoms to the National Institute of Standards and Technology (NIST), called Green and Pink, and asked to have the phantoms’ volumes estimated. This report describes in detail both the metrology and computational methods used to estimate the phantoms’ volumes. Three sets of coordinate measuring machine (CMM) measured data were produced. One set of data involved reference surface data measurements of a known calibrated metal sphere. The other two sets were measurements of the two FDA phantoms at two densities, called the coarse set and the dense set. Two computational approaches were applied to the data. In the first approach spherical models were fit to the calibrated sphere data and to the phantom data. The second approach was to model the data points on the boundaries of the spheres with surface B-splines and then use the Divergence Theorem to estimate the volumes. Fitting a B-spline model to the calibrated sphere data was done as a reference check on the algorithm performance. It gave assurance that the volumes estimated for the phantoms would be meaningful. The results for the coarse and dense data sets tended to predict the volumes as expected and the results did show that the Green phantom was very near spherical. This was confirmed by both computational methods. The spherical model did not fit the Pink phantom as well and the B-spline approach provided a better estimate of the volume in that case.     

Prediction of the freezing point of multicomponent liquid refrigerant solutions

The freezing point is one of the most critical properties required to complete the mathematical formulation related to the transport phenomena involved in the immersion chilling and freezing (ICF) of foods. Unfortunately, data for ternary and higher order systems are scarce. The aim of this work was to verify the validity of an excess Gibbs energy model for predicting the freezing point of multicomponent mixtures of electrolytes and non-electrolytes, considering the processing conditions used in immersion chilling and freezing of foods. The extended UNIQUAC model was used. Data obtained from literature corresponding to freezing points of the ternary systems: NaCl-KCl-H₂O, NaCl-CaCl₂-H₂O, NaCl-MgCl₂-H₂O and NaCl-EtOH-H₂O, were compared with predicted values. The model accuracy was satisfactory, the highest absolute deviation being smaller than 1.71 °C for the 378 data compared.