Bioremediation with White-Rot Fungi at Fisherville Mill: Analyses of Gene Expression and Number 6 Fuel Oil Degradation

Extracellular enzymes that white-rot fungi secrete during lignin decay have been proposed as promising agents for oxidizing pollutants. We investigated the abilities of the white-rot fungi Punctularia strigosozonata, Irpex lacteus, Trichaptum biforme, Phlebia radiata, Trametes versicolor, and Pleurotus ostreatus to degrade Number 6 fuel oil in wood sawdust cultures. Our goals are to advise bioremediation efforts at a brownfield redevelopment site on the Blackstone River in Grafton, Massachusetts and to contribute to the understanding of decay mechanisms in white-rot fungi. All species tested degraded a C10 alkane. When cultivated for 6 months, Irpex lacteus, T. biforme, P. radiata, T. versicolor and P. ostreatus also degraded a C14 alkane and the polycyclic aromatic hydrocarbon phenanthrene. Gene expression analyses of P. strigosozonata indicate differential gene expression in the presence of Number 6 oil and on pine and aspen sawdust

Characterization of dentine to assess bond strength of dental composites

This study was performed to develop alternating dentine adhesion models that could help in the evaluation of a self-bonding dental composite. For this purpose dentine from human and ivory was characterized chemically and microscopically before and after acid etching using Raman and SEM. Mechanical properties of dentine were determined using 3 point bend test. Composite bonding to dentine, with and without use of acid pre-treatment and/or the adhesive, were assessed using a shear bond test. Furthermore, micro gap formation after restoration of 3 mm diameter cavities in dentine was assessed by SEM. Initial hydroxyapatite level in ivory was half that in human dentine. Surface hydroxyapatites decreased by approximately half with every 23 s of acid etch. The human dentine strength (56 MPa) was approximately double that of ivory, while the modulus was almost comparable to that of ivory. With adhesive use, average shear bond strengths were 30 and 26 MPa with and without acid etching. With no adhesive, average bond strength was 6 MPa for conventional composites. This, however, increased to 14 MPa with a commercial flowable "self-bonding" composite or upon addition of low levels of an acidic monomer to the experimental composite. The acidic monomer additionally reduced micro-gap formation with the experimental composite. Improved bonding and mechanical properties should reduce composite failures due to recurrent caries or fracture respectively

Newly Acquired Fear of Falling Leads to Altered Eye Movement Patterns and Reduced Stepping Safety: A Case Study

This opportune case study describes visual and stepping behaviours of an 87 year old female (P8), both prior to, and following two falls. Before falling, when asked to walk along a path containing two stepping guides positioned before and after an obstacle, P8 generally visually fixated the first stepping guide until after foot contact inside it. However, after falling P8 consistently looked away from the stepping guide before completing the step into it in order to fixate the upcoming obstacle in her path. The timing of gaze redirection away from the target (in relation to foot contact inside it) correlated with absolute stepping error. No differences in eyesight, cognitive function, or balance were found between pre- and post-fall recordings. However, P8 did report large increases in fall-related anxiety and reduced balance confidence, supporting previously suggested links between anxiety/increased fear or falling and maladaptive visual/stepping behaviours. The results represent a novel insight into how psychological and related behavioural factors can change in older adults following a fall, and provide a possible partial rationalisation for why recent fallers are more likely to fall again in the following 12 months. These findings highlight novel possibilities for falls prevention and rehabilitation

A geometrical formulation of the μ-lower bound problem

A new problem formulation for the structured singular value μ in the case of purely real (possibly repeated) uncertainties is presented. The approach is based on a geometrical interpretation of the singularity constraint arising in the μ lower bound problem. An interesting feature of this problem formulation is that the resulting parametric search space is independent of the number of times any parameter is repeated in the structured uncertainty matrix. A corresponding lower bound algorithm combining randomisation and optimisation methods is developed, and some probabilistic performance guarantees are derived. The potential usefulness of the proposed approach is demonstrated on two high-order real μ analysis problems from the aerospace and systems biology literature

Automated identification of Fos expression

The concentration of Fos, a protein encoded by the immediate-early gene c-fos, provides a measure of synaptic activity that may not parallel the electrical activity of neurons. Such a measure is important for the difficult problem of identifying dynamic properties of neuronal circuitries activated by a variety of stimuli and behaviours. We employ two-stage statistical pattern recognition to identify cellular nuclei that express Fos in two-dimensional sections of rat forebrain after administration of antipsychotic drugs. In stage one, we distinguish dark-stained candidate nuclei from image background by a thresholding algorithm and record size and shape measurements of these objects. In stage two, we compare performance of linear and quadratic discriminants, nearest-neighbour and artificial neural network classifiers that employ functions of these measurements to label candidate objects as either Fos nuclei, two touching Fos nuclei or irrelevant background material. New images of neighbouring brain tissue serve as test sets to assess generalizability of the best derived classification rule, as determined by lowest cross-validation misclassification rate. Three experts, two internal and one external, compare manual and automated results for accuracy assessment. Analyses of a subset of images on two separate occasions provide quantitative measures of inter- and intra-expert consistency. We conclude that our automated procedure yields results that compare favourably with those of the experts and thus has potential to remove much of the tedium, subjectivity and irreproducibility of current Fos identification methods in digital microscopy

A Study of Low GWP Refrigerants for Transport Refrigeration based on Hermetic Scroll Compressors with an Economizer

One hermetic scroll compressor with an economizer port that is built initially for R404A has been tested with R404A in a compressor calorimeter. The testing has been completed on several running conditions to create a compressor operating map. Based on this map, a compressor efficiency model has been created. This model has been used to calculate capacity, COP and discharge temperature for frozen and fresh conditions in the transport refrigeration application with R452A, R454A and R454C. The capacity, COP and discharge temperature for those frozen and fresh conditions are compared with R404A. Another hermetic scroll compressor with an economizer port that is built initially for R134a has been tested with R134a in a compressor calorimeter. The testing has been completed on several running conditions to create a compressor operating map. Based on this map, a compressor efficiency model has been created. This model has been used to calculate capacity, COP and discharge temperature for frozen and fresh conditions in the transport refrigeration application with R513A and R1234yf. The capacity, COP and discharge temperature for those frozen and fresh conditions are compared with R134a. Furthermore, a general comparison is made between the two different compressors and the two different refrigerants, where one is tested on R404A and the other is tested on R134a. In this case, COP and discharge temperature is compared. Since some of the refrigerants have glide characteristics, calculations based on dew-point and mid-point are compared

Poly[[triaqua­[μ4-N-(4-carboxyl­ato­phenyl)­iminodiacetato]sodium(I)zinc(II)] dihydrate]

In the title coordination polymer, {[NaZn(C11H8NO6)(H2O)3]·2H2O}n, the Zn atom is coordinated in a distorted tetra­hedral environment by three carboxyl­ate O atoms from two (4-carboxyl­atophenyl­imino)diacetate ligands and one water mol­ecule; the Na atom is in an distorted octa­hedral coordination environment formed by four carboxyl­ate O atoms from three (4-carboxyl­atophenyl­imino)diacetate ligands and two water mol­ecules. The Zn atoms and Na atoms are linked by (4-carboxyl­atophenyl­imino)diacetate ligands into a three-dimensional framework; the uncoordinated water mol­ecules fill the voids of the skeleton and stabilize it by O—H⋯O hydrogen bonds