Scaffold-free, Human Mesenchymal Stem Cell-Based Tissue Engineered Blood Vessels.

Tissue-engineered blood vessels (TEBV) can serve as vascular grafts and may also play an important role in the development of organs-on-a-chip. Most TEBV construction involves scaffolding with biomaterials such as collagen gel or electrospun fibrous mesh. Hypothesizing that a scaffold-free TEBV may be advantageous, we constructed a tubular structure (1 mm i.d.) from aligned human mesenchymal cell sheets (hMSC) as the wall and human endothelial progenitor cell (hEPC) coating as the lumen. The burst pressure of the scaffold-free TEBV was above 200 mmHg after three weeks of sequential culture in a rotating wall bioreactor and perfusion at 6.8 dynes/cm(2). The interwoven organization of the cell layers and extensive extracellular matrix (ECM) formation of the hMSC-based TEBV resembled that of native blood vessels. The TEBV exhibited flow-mediated vasodilation, vasoconstriction after exposure to 1 μM phenylephrine and released nitric oxide in a manner similar to that of porcine femoral vein. HL-60 cells attached to the TEBV lumen after TNF-α activation to suggest a functional endothelium. This study demonstrates the potential of a hEPC endothelialized hMSC-based TEBV for drug screening.

Genomics and virulence factors of Fusobacterium necrophorum

Fusobacterium necrophorum, a Gram negative, anaerobic bacterium, is a common cause of acute pharyngitis and tonsillitis and a rare cause of more severe infections of the head and neck. At the beginning of the project, there was no available genome sequence for F. necrophorum. The aim of this project was to sequence the F. necrophorum genome and identify and study its putative virulence factors contained using in silico and in vitro analysis. Type strains JCM 3718 and JCM 3724,F. necrophorum subspecies necrophorum (Fnn) and funduliforme (Fnf), respectively, and strain ARU 01 (Fnf), isolated from a patient with LS, were commercially sequenced by Roche 454 GS-FLX+ next generation sequencing and assembled into contigs using Roche GS Assembler. Sequence data was annotated semi-automatically, using the xBASE pipeline, BLASTp and Pfam. The F. necrophorum genome was determined to be approximately 2.1 – 2.3 Mb in size, with an estimated 1,950 ORFs and includes genes for a leukotoxin, ecotin, haemolysin, haemagglutinin, haemin receptor, adhesin and type Vb and Vc secretion systems. The prevalence of the leukotoxin gene was investigated in strains JCM 3718, JCM 3724 and ARU 01, as well as a clinical collection of 25 Fnf strains, identified using biochemical and molecular tests. The leukotoxin operon was found to be universal within the strain collection by PCR. HL-60 cells subjected to aliquots of concentrated high molecular weight culture supernatant, predicted to contain the secreted leukotoxins of strains JCM 3718, JCM 3724 and ARU 01, were killed in a dose-dependent manner. The cytotoxic effect of the leukotoxin against human donor white blood cells was also tested to validate the HL-60 assay. The differences in the results between the two assays were not statistically significant. Ecotin, a serine protease inhibitor, was found to be present in 100 % of the strain collection and had a highly conserved sequence with primary and secondary binding sites exposed on opposing sides of the protein. During enzyme inhibition studies, a purified recombinant F. necrophorum ecotin protein inhibited human neutrophil elastase, a protease that degrades bacteria at inflammation sites, and human plasma kallikrein, a component of the host clotting cascade. The recombinant ecotin also prolonged human plasma clotting times by up to 7-fold for the extrinsic pathway, and up to 40-fold for the intrinsic pathway. The genome sequence data provides important information about F. necrophorum type strains and enables comparative study between strains and subspecies. Results from the leukotoxin and ecotin assays can be used to build up an understanding of how the organism behaves during infection.

Revision total hip replacement using the cement-in-cement technique for the acetabular component : technique and results for 60 hips

The technique of femoral cement-in-cement revision is well established, but there are no previous series reporting its use on the acetabular side at the time of revision total hip arthroplasty. We describe the surgical technique and report the outcome of 60 consecutive cement-in-cement revisions of the acetabular component at a mean follow-up of 8.5 years (range 5-12 years). All had a radiologically and clinically well fixed acetabular cement mantle at the time of revision. 29 patients died. No case was lost to follow-up. The 2 most common indications for acetabular revision were recurrent dislocation (77%) and to compliment a femoral revision (20%). There were 2 cases of aseptic cup loosening (3.3%) requiring re-revision. No other hip was clinically or radiologically loose (96.7%) at latest follow-up. One case was re-revised for infection, 4 for recurrent dislocation and 1 for disarticulation of a constrained component. At 5 years, the Kaplan-Meier survival rate was 100% for aseptic loosening and 92.2% (95% CI; 84.8-99.6%) with revision for all causes as the endpoint. These results support the use of the cement-in-cement revision technique in appropriate cases on the acetabular side. Theoretical advantages include preservation of bone stock, reduced operating time, reduced risk of complications and durable fixation.

Preparing high achieving English teachers to work in disadvantaged schools : 'I'll teach Shakespeare when I'm 60'

The recent release of the Gonski Review recognises the decline in Australia’s schooling performances over the last decade, noting in particular a distressing increase in the ‘achievement gap’ affecting students from low SES backgrounds (Gonski, 2012). The report details the need for more quality in teachers throughout the schooling system, particularly within the schools with the greatest academic needs. This paper specifically focuses on a group of high-achieving pre-service English teachers. In their last two years of university study, they participated in a program called Exceptional Teachers for Disadvantaged Schools (ETDS), designed to prepare them to work in disadvantaged or low SES schools. We wanted to capture their experiences of teaching in challenging settings during their practicum, and as they prepared to graduate, we wondered what they now felt about teaching English in low SES schools. Using narrative inquiry, we analysed a range of reflective data to gain insight into such things as their initial motivations for entering the teaching profession and how their preconceived expectations may or may not have shifted after practicum experiences in low SES schools. We encouraged open reflection about how they perceived themselves as English teachers.

Experimental study on creep and shrinkage of high-performance ultra-lightweight cement composite of 60 MPa

Creep and shrinkage behaviour of an ultra lightweight cement composite (ULCC) up to 450 days was evaluated in comparison with those of a normal weight aggregate concrete (NWAC) and a lightweight aggregate concrete (LWAC) with similar 28-day compressive strength. The ULCC is characterized by low density < 1500 kg/m3 and high compressive strength about 60 MPa. Autogenous shrinkage increased rapidly in the ULCC at early-age and almost 95% occurred prior to the start of creep test at 28 days. Hence, majority of shrinkage of the ULCC during creep test was drying shrinkage. Total shrinkage of the ULCC during the 450-day creep test was the lowest compared to the NWAC and LWAC. However, corresponding total creep in the ULCC was the highest with high proportion attributed to basic creep (≥ ~90%) and limited drying creep. The high creep of the ULCC is likely due to its low elastic modulus. Specific creep of the ULCC was similar to that of the NWAC, but more than 80% higher than the LWAC. Creep coefficient of the ULCC was about 47% lower than that of the NWAC but about 18% higher than that of the LWAC. Among five creep models evaluated which tend to over-estimate the creep coefficient of the ULCC, EC2 model gives acceptable prediction within +25% deviations. The EC2 model may be used as a first approximate for the creep of ULCC in the designs of steel-concrete composites or sandwich structures in the absence of other relevant creep data.

Polybrominated diphenyl ethers and age: analysis of pooled human blood serum from birth to over 60 years

Polybrominated diphenyl ethers (PBDEs) are considered to be a cost effective and efficient way to reduce flammability therefore reducing harm caused by fires. PBDEs are incorporated into a variety of manufactured products and are found worldwide in biological and environmental samples (e.g. Hites et al. 2004). Unlike other persistent organic pollutants there is limited data on PBDE concentrations by age and/or other population specific factors. Some studies have shown no variation in adult serum PBDE concentrations with age (e.g. Mazdai et al., 2003, Meironyte Guvenius et al., 2003) while Petreas et al. (2003) and Schecter et al. (2005) found results to be suggestive of an age trend in adult data but no statistically significant correlation was found. In addition to the data on adult concentrations there is limited data which investigates the levels of PBDEs in infants and young children. Fangström et al. (2005) showed that in seven year olds there was no difference in PBDE concentration when compared to adult concentrations. While Thomsen et al. (2002, 2005) found the concentration of PBDEs in pooled samples of blood serum from a 0-4 years age group to be higher than other age groups (4 to > 60 years). In addition, a family of four was studied in the U.S. and the concentrations were found to be greatest in the 18-month-old infant followed by the 5 year old child, then the mother and father (Fischer et al., 2006). The objectives of this study were to assess age, gender and regional trends of PBDE concentrations in a representative sample of the Australian population.

A New Mechanism For Ferromagnetism In C-60-TDAE

Based on the topology of C-60 and the resulting non-disjoint nature of the lowest unoccupied molecular orbitals, Ne propose a new model for ferromagnetic exchange in C-60-TDAE. Within the Hubbard model, we find that the ferromagnetic exchange integral is stabilized to first order in the inter-ball transfer integral, while the antiferromagnetic coupling is stabilized only to second order. This difference is adequate to counter the larger phase space available for stabilizing the antiferromagnetic state. Thus, the ground state is found to be ferromagnetic for reasonable inter-ball transfer integrals.

Structural and functional studies of Bacillus stearothermophilus serine hydroxymethyltransferase: the role of Asn(341), Tyr(60) and Phe(351) in tetrahydrofolate binding

SHMT (serine hydoxymethyltransferase), a type I pyridoxal 5'-phosphate-dependent enzyme, catalyses the conversion of L-serine and THF (tetrahydrofolate) into glycine and 5,10-methylene THE SHMT also catalyses several THF-independent side reactions such as cleavage of P-hydroxy amino acids, trans-amination, racemization and decarboxylation. In the present study, the residues Asn(341), Tyr(60) and Phe(351), which are likely to influence THF binding, were mutated to alanine, alanine and glycine respectively, to elucidate the role of these residues in THF-dependent and -independent reactions catalysed by SHMT. The N341A and Y60A bsSHMT (Bacillus stearothermophilus SHMT) mutants were inactive for the THF-dependent activity, while the mutations had no effect on THF-independent activity. However, mutation of Phe(351) to glycine did not have any effect oil either of the activities. The crystal structures of the glycine binary complexes of the mutants showed that N341A bsSHMT forms an external aldimine as in bsSHMT, whereas Y60A and F351G bsSHMTs exist as a Mixture of internal/external aldimine and gem-diamine forms. Crystal structures of all of the three Mutants obtained in the presence of L-allo-threonine were similar to the respective glycine binary complexes. The structure of the ternary complex of F351G bsSHMT with glycine and FTHF (5-formyl THF) showed that the monoglutamate side chain of FTHF is ordered in both the subunits of the asymmetric unit, unlike in the wild-type bsSHMT. The present studies demonstrate that the residues Asn(341) and Tyr(60) are pivotal for the binding of THF/FTHF, whereas Phe(351) is responsible for the asymmetric binding of FTHF in the two subunits of the dimer.

Costs assessment not an each-way bet: Radich v Kenway [2014] QDC 60

In Radich v Kenway [2014] QDC 60 McGinness DCJ considered issues relating to the assessment of costs under the Legal Profession Act 2007 (Qld). This recent costs assessment case from the District Court clearly illustrates the interplay between the relevant elements of the Legal Profession Act 2007 and Uniform Civil Procedure Rules 1999.

Spatial and temporal variability in midge (Nematocera) assemblages in shallow Finnish lakes (60−70 °N) : community-based modelling of past environmental change

Multi- and intralake datasets of fossil midge assemblages in surface sediments of small shallow lakes in Finland were studied to determine the most important environmental factors explaining trends in midge distribution and abundance. The aim was to develop palaeoenvironmental calibration models for the most important environmental variables for the purpose of reconstructing past environmental conditions. The developed models were applied to three high-resolution fossil midge stratigraphies from southern and eastern Finland to interpret environmental variability over the past 2000 years, with special focus on the Medieval Climate Anomaly (MCA), the Little Ice Age (LIA) and recent anthropogenic changes. The midge-based results were compared with physical properties of the sediment, historical evidence and environmental reconstructions based on diatoms (Bacillariophyta), cladocerans (Crustacea: Cladocera) and tree rings. The results showed that the most important environmental factor controlling midge distribution and abundance along a latitudinal gradient in Finland was the mean July air temperature (TJul). However, when the dataset was environmentally screened to include only pristine lakes, water depth at the sampling site became more important. Furthermore, when the dataset was geographically scaled to southern Finland, hypolimnetic oxygen conditions became the dominant environmental factor. The results from an intralake dataset from eastern Finland showed that the most important environmental factors controlling midge distribution within a lake basin were river contribution, water depth and submerged vegetation patterns. In addition, the results of the intralake dataset showed that the fossil midge assemblages represent fauna that lived in close proximity to the sampling sites, thus enabling the exploration of within-lake gradients in midge assemblages. Importantly, this within-lake heterogeneity in midge assemblages may have effects on midge-based temperature estimations, because samples taken from the deepest point of a lake basin may infer considerably colder temperatures than expected, as shown by the present test results. Therefore, it is suggested here that the samples in fossil midge studies involving shallow boreal lakes should be taken from the sublittoral, where the assemblages are most representative of the whole lake fauna. Transfer functions between midge assemblages and the environmental forcing factors that were significantly related with the assemblages, including mean air TJul, water depth, hypolimnetic oxygen, stream flow and distance to littoral vegetation, were developed using weighted averaging (WA) and weighted averaging-partial least squares (WA-PLS) techniques, which outperformed all the other tested numerical approaches. Application of the models in downcore studies showed mostly consistent trends. Based on the present results, which agreed with previous studies and historical evidence, the Medieval Climate Anomaly between ca. 800 and 1300 AD in eastern Finland was characterized by warm temperature conditions and dry summers, but probably humid winters. The Little Ice Age (LIA) prevailed in southern Finland from ca. 1550 to 1850 AD, with the coldest conditions occurring at ca. 1700 AD, whereas in eastern Finland the cold conditions prevailed over a longer time period, from ca. 1300 until 1900 AD. The recent climatic warming was clearly represented in all of the temperature reconstructions. In the terms of long-term climatology, the present results provide support for the concept that the North Atlantic Oscillation (NAO) index has a positive correlation with winter precipitation and annual temperature and a negative correlation with summer precipitation in eastern Finland. In general, the results indicate a relatively warm climate with dry summers but snowy winters during the MCA and a cool climate with rainy summers and dry winters during the LIA. The results of the present reconstructions and the forthcoming applications of the models can be used in assessments of long-term environmental dynamics to refine the understanding of past environmental reference conditions and natural variability required by environmental scientists, ecologists and policy makers to make decisions concerning the presently occurring global, regional and local changes. The developed midge-based models for temperature, hypolimnetic oxygen, water depth, littoral vegetation shift and stream flow, presented in this thesis, are open for scientific use on request.

Relationship Drivers in Provider - Consumer Relationships. Empirical Studies of Customer Loyalty Programs (första upplagan slutsåld / first edition sold out, 'print on demand' 60 €)

The study addressed a phenomenon that has become common marketing practice, customer loyalty programs. Although a common type of consumer relationship, there is limited knowledge of its nature. The purpose of the study was to create structured understanding of the nature of customer relationships from both the provider’s and the consumer’s viewpoints by studying relationship drivers and proposing the concept of relational motivation as a provider of a common framework for the analysis of these views. The theoretical exploration focused on reasons for engaging in customer relationships for both the consumer and the provider. The themes of buying behaviour, industrial and network marketing and relationship marketing, as well as the concepts of a customer relationship, customer loyalty, relationship conditions, relational benefits, bonds and commitment were explored and combined in a new way. Concepts from the study of business-to-business relationships were brought over and their power in explaining the nature of consumer relationships examined. The study provided a comprehensive picture of loyalty programs, which is an important contribution to the academic as well as the managerial discussions. The consumer study provided deep insights into the nature of customer relationships. The study provides a new frame of reference to support the existing concepts of loyalty and commitment with the introduction of the relationship driver and relational motivation concepts. The result is a novel view of the nature of customer relationships that creates new understanding of the forces leading to loyal behaviour and commitment. The study concludes with managerial implications.