Properties of fish protein–hydrophilic polymer hybrid gels

Summary Biogels and bio-hybrid gels were prepared from myofibril of fish and their properties were evaluated. The muscular protein used was extracted from fish meat. After washing and centrifugal separation, the muscular protein was mixed with 3 wt % of NaCl and the gels were prepared by heating the mixtures from 50 to 90 °C. The bio-hybrid gels were prepared from fish protein gel and poly(vinyl alcohol). Tensile tests revealed that the tensile strength, strain at break and Young’s modulus of heated hybrid gels prepared at 50, 80 and 90 °C increased with increasing preparation temperature. This can be explained by the difference in crosslinking density. Also, the heated gels showed a good response to electric field in acid and alkaline solutions. Young modulus, tensile strength and elongation at break of the bio-hybrid gels increased with an increasing PVA content. Bending of hybrid gels in solutions of various pH under the electric stimulus was observed. The largest bending angle was 20–30 °C at pH=1.2.     

Reconciling Electrical Resistance Tomography (ERT) Measurements with a Fluid Mixing Model for Semi‐Batch Operation of a Stirred Vessel

An electrical resistance tomography (ERT) system retrofitted to a 2.3 m³ vessel has been used to image the vessel volume for single feed semi‐batch operation. Images reconstructed from the raw ERT measurements may be represented as time incremented 3‐D iso‐surface representations of the fluid mixing. ERT derived mixing curves have been evaluated against a network of zones (NOZ) mixing model, which is able to compute the time evolving concentration fields. Like the ERT system, the NOZ model is also able to visualise the evolving feed plume and has the power to predict the corresponding time‐wise reaction behaviour in space for a simple A + B → products reaction.     

Infective spondylodiscitis in patients on high‐flux hemodialysis and on‐line hemodiafiltration

Infective spondylodiscitis (ISD) is a rare but potentially devastating condition in hemodialysis (HD) patients. Reports are limited especially in patients receiving high‐flux HD and hemodiafiltration (HDF). In a retrospective analysis, 13 patients on our maintenance high‐flux HD/HDF program were identified as having has infective spondylodiscitis over a 10‐year period (1997–2006), an incidence of approximately 1 episode every 215 patient‐years. The incidence was around 3 times higher in patients dialyzing with tunnelled central venous catheters (TCVC) than in those with arteriovenous fistulae. Affected patients were elderly (mean age 70 years) and had multiple comorbidities. Access problems, particularly TCVC infection, were common in the months preceding it's onset. Tunnelled central venous catheter removal during these episodes did not necessarily prevent it. Diagnosis was based on a history of back pain, raised C‐reactive protein, positive blood cultures, and characteristic magnetic resonance findings. Many patients were apyrexial and had normal white cell counts. In our patients on high‐flux HD/hemodiafiltration, its incidence appears comparable to that in conventional HD settings. No patients had infection with waterborne organisms. Blood cultures were positive in 77%. Gram‐positive organisms predominated, particularly Staphylococcus aureus. The major route of infection was hematogenous, with the most likely source the venous access. All received antibiotics for 6 to 12 weeks or until death. Only 2 patients underwent surgical drainage. Mortality was high (46%) and predicted by the development of complications, and by pre‐existing cardiovascular comorbidity. Prevention, using strategies to reduce the prevalence of bacteremia, including limiting the use of TCVC, should be an overriding aim.     

Inevitability of nTP: information — energy carriers

Adenine is naturally selected as the main energy carrier from among two types of purines. C. Duve mentions that the inevitability of adenosine triphosphate (ATP) is still a mystery. We examined the databases of DNA, RNA, and codon in order to clarify whether guanosine triphosphate (GTP) is mainly used for information storage in nucleic acids, because the adenine-uracil pair with a weaker connection would be dropped out relatively among the information carrier candidates due to natural selection. This paper presents a simple hypothesis that the relatively lower rates of adenine (A) and uracil (U) than the rates of guanine (G) and cytosine (C) observed in the RNAs for a lot of species cause redundant monomers of ATP and uridine triphosphate (UTP) outside nucleic acids, which become energy carriers. ATP runoff from RNA resembles the joker (or remaining unmatched queen) in the card game of Old Maid. The other redundant monomers of UTP might become polysaccharide generators. Actual frequencies of G and C in the RNAs of hyper-thermophiles are more than double those of A and U. A-U pairs are also fewer in number than G-C pairs in microorganisms such as yeast. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

Learning better IV&V practices

After data mining National Aeronautics and Space Administration (NASA) independent verification and validation (IV&V) data, we offer (a) an early life cycle predictor for project issue frequency and severity; (b) an IV&V task selector (that used the predictor to find the appropriate IV&V tasks); and (c) pruning heuristics describing what tasks to ignore, if the budget cannot accommodate all selected tasks. In ten-way cross-validation experiments, the predictor performs very well indeed: the average f-measure for predicting four classes of issue severity was over 0.9. This predictor is built using public-domain data and software. To the best of our knowledge, this is the first reproducible report of a predictor for issue frequency and severity that can be applied early in the life cycle. This research was conducted at West Virginia University and the NASA IV&V Facility under NASA subcontract project 100005549, task 5e, award 1002193r. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not constitute or imply its endorsement by the United States Government. See for an earlier draft.     

A technological model to define access to electronic clinical records.

This communication describes a functioning model that permits access to an electronic health record across a small number of providers resident in an Australian regional setting. Design criteria designated that provider access rights were to be assignable, revokable, transportable, and informable.     

Microstructure and mechanical properties of magnesium AZ31 sheets produced by extrusion

In the last decade magnesium has regained importance for lightweight and transportation industries since it is the lightest metal for structural applications. Therefore the increasing demand of sheet-like magnesium applications required manifold forming strategies. The extrusion is an alternative solution for the production of magnesium sheets and thin flat profiles, which are produced today mainly by rolling. This study presents the influence of the process temperature and extrusion ratio on the microstructure and mechanical properties of AZ31 extrusion sheets. The extruded sheets exhibit a coarse-grained microstructure and a pronounced mechanical anisotropy in the sheet plane caused by the extrusion texture. This texture leads to a strong dependence of deformation systems on the loading direction delivering the highest value for yielding in extrusion direction, but the lowest in transverse direction due to the easy activation of the {10-12}<10-11> extension twinning system in favorably oriented grains.     

A neural network approach to predict tactile comfort of applying cosmetic foundation

An expert system has been developed to predict the degree of tactile comfort during the application of cosmetic foundation. A tribometer using compliant silicone-rubber surfaces was developed to perform 4 sliding tests and an oscillating test. From the tests for 20 different samples, 11 feature quantities were identified. The values of the feature quantities were used as the inputs to an artificial neural network, and the scores of tactile sensations were obtained as the outputs. The neural network, after supervised learning, could predict 5 types of emotional tactile comfort with high accuracy.     

Use of back-scatter electron signals to visualise cell/nanowires interactions in vitro and in vivo; frustrated phagocytosis of long fibres in macrophages and compartmentalisation in mesothelial cells in vivo

ABSTRACT: BACKGROUND: Frustrated phagocytosis has been stated as an important factor in the initiation of an inflammatory response after fibre exposure. The length of fibrous structures has been linked to the potential of fibres to induce adverse health effects for at least 40 years. However, we only recently reported for the first time the threshold length for fibre-induced inflammation in the pleural space and we implicated frustrated phagocytosis in the pro-inflammatory effects of long fibres. This study extends the examination of the threshold value for frustrated phagocytosis using well-defined length classes of silver nanowires (AgNW) ranging from 3--28 mum and describes in detail the morphology of frustrated phagocytosis using a novel technique and also describes compartmentalisation of fibres in the pleural space. METHODS: A novel technique, backscatter scanning electron microscopy (BSE) was used to study frustrated phagocytosis since it provides high-contrast detection of nanowires, allowing clear discrimination between the nanofibres and other cellular features. A human monocyte-derived macrophage cell line THP-1 was used to investigate cell-nanowire interaction in vitro and the parietal pleura, the site of fibre retention after inhalation exposure was chosen to visualise the cell- fibre interaction in vivo after direct pleural installation of AgNWs. RESULTS: The length cut-off value for frustrated phagocytosis differs in vitro and in vivo. While in vitro frustrated phagocytosis could be observed with fibres [GREATER-THAN OR EQUAL TO]14 mum, in vivo studies showed incomplete uptake at a fibre length of [GREATER-THAN OR EQUAL TO]10 mum. Recently we showed that inflammation in the pleural space after intrapleural injection of the same nanofibre panel occurs at a length of [GREATER-THAN OR EQUAL TO]5 mum. This onset of inflammation does not correlate with the onset of frustrated phagocytosis as shown in this study, leading to the conclusion that intermediate length fibres fully enclosed within macrophages as well as frustrated phagocytosis are associated with a pro-inflammatory state in the pleural space. We further showed that fibres compartmentalise in the mesothelial cells at the parietal pleura as well as in inflammatory cells in the pleural space. CONCLUSION: BSE is a useful way to clearly distinguish between fibres that are, or are not, membrane-bounded. Using this method we were able to show differences in the threshold length at which frustrated phagocytosis occurred between in vitro and in vivo models. Visualising nanowires in the pleura demonstrated at least 2 compartments -- in leukocyte aggregations and in the mesothelium - which may have consequences for long term pathology in the pleural space including mesothelioma.