In vitro assessment of migratory behavior of two cell populations in a simple multichannel microdevice

Recent literature suggests that mesenchymal stem/stromal cells (MSC) could be used as Trojan Horses to deliver “death-signals” to cancer cells. Herein, we describe the development of a novel multichannel cell migration device, and use it to investigate the relative migration rates of bone marrow-derived MSC and breast cancer cells (MCF-7) towards each other. Confluent monolayers of MSC and MCF-7 were established in adjacent chambers separated by an array of 14 microchannels. Initially, culture chambers were isolated by air bubbles (air-valves) contained within each microchannel, and then bubbles were displaced to initiate the assay. The MCF-7 cells migrated preferentially towards MSC, whilst the MSC did not migrate preferentially towards the MCF-7 cells. Our results corroborate previous literature that suggests MSC migration towards cancer cells in vivo is in response to the associated inflammation rather than directly to signals secreted by the cancer cells themselves.

The dimensions of travel journalism : exploring new fields for journalism research beyond the news

Much of the existing empirical research on journalism focuses largely on hard-news journalism, at the expense of its less traditional forms, particularly the soft-news areas of lifestyle and entertainment journalism. In focussing on one particular area of lifestyle journalism – the reporting of travel stories – this paper argues for renewed scholarly efforts in this increasingly important field. Travel journalism’s location at the intersection between information and entertainment, journalism and advertising, as well as its increasingly significant role in the representation of foreign cultures makes it a significant site for scholarly research. By reviewing existing research about travel journalism and examining in detail the special exigencies that constrain it, the article proposes a number of dimensions for future research into the production practices of travel journalism. These dimensions include travel journalism’s role in mediating foreign cultures, its market orientation, motivational aspects and its ethical standards.

A profile of Australian travel journalists' professional views and ethical standards

Despite significant changes in mainstream journalism in recent decades, journalistic fields beyond the news have been little explored. In an attempt to contribute to a deeper understanding of such fields, this article examines the role perceptions of 85 Australian travel journalists. By viewing travel journalism as a distinct field of practice that is affected by a unique mix of influences, this study identifies five dimensions of practitioners’ role perceptions. These relate to travel journalists’ views of themselves as Cultural Mediators, Critics, Entertainers, Information Providers and Travellers. In addition, the study examines in some depth the ethical standards of travel journalists. Determinants of these views and standards are explored. The study argues that, in light of travel journalists’ increasingly important role in reporting about foreign places, more remains to be done to promote travel stories that show a deeper understanding of other cultures and which contain a more critical appraisal of destinations.

Travel journalists’ attitudes toward public relations : findings from a representative survey

The impact of public relations on emerging fields such as travel journalism has not gained much attention, despite the broader growth of lifestyle journalism, and its particular dependence on PR. This study reports the findings of a representative survey of Australian travel journalists, focusing on their views of PR. Results show that travel journalists are wary of PR, although they believe they can be relatively immune from its influence and see some PR activities as quite useful. Cluster analysis identifies three distinct groups based on their views of PR, which range from a positive attitude to strong criticism. Their backgrounds and differences are explored, pointing to gender, job status, and background in mainstream journalism as main determinants for differences.

The geography of travel journalism : mapping the flow of travel stories about foreign countries

While the study of foreign news flows has received considerable attention from communication scholars for quite some time, it has typically focused on political or ‘hard’ news, at the expense of other types of journalistic content. This article argues that, as the foreign news hole is shrinking, travel journalism is becoming an increasingly important source of information about foreign countries in the news media. It reports the results of a comparative study of newspaper travel sections in Australia, Canada, New Zealand, and the UK, and argues that travel journalism often replicates the imbalances found in foreign news flows. Well-known factors – such as regionalism, powerful nations, cultural proximity, the role played by big neighbours and the diversity of coverage – are also powerful determinants in travel journalism. At the same time, a country’s tourist behaviour also plays a role but is often overshadowed by other factors.

Representations of foreign places outside the news : an analysis of Australian newspaper travel sections

Despite continued growth over recent decades, travel journalism has so far gained little attention in journalism research, with scholars often ridiculing it and other forms of lifestyle journalism as not being real journalism. This paper aims to the shift the focus by arguing that non-news journalism is increasingly important as a site for research. It reports the results from a content analysis of Australian newspaper travel sections and examines the role they play in mediating foreign places. The results demonstrate that travel stories can be mostly classed as service stories in that they focus on destinations which are already popular with Australians. At the same time they report very little about local cultures at the destinations, demonstrating a focus on the tourist experience and a missed opportunity for improving inter-cultural understanding. A visual analysis of photographs shows stereotypical portrayals of destinations broadly in line with tourism promotion materials.

The reduced expression of the HADH2 protein causes X-linked mental retardation, choreoathetosis, and abnormal behavior

Recently, we defined a new syndromic form of X-linked mental retardation in a 4-generation family with a unique clinical phenotype characterized by mild mental retardation, choreoathetosis, and abnormal behavior (MRXS10). Linkage analysis in this family revealed a candidate region of 13.4 Mb between markers DXS1201 and DXS991 on Xp11; therefore, mutation analysis was performed by direct sequencing in most of the 135 annotated genes located in the region. The gene (HADH2) encoding L-3-hydroxyacyl-CoA dehydrogenase II displayed a sequence alteration (c.574 C-->A; p.R192R) in all patients and carrier females that was absent in unaffected male family members and could not be found in 2,500 control X chromosomes, including in those of 500 healthy males. The silent C-->A substitution is located in exon 5 and was shown by western blot to reduce the amount of HADH2 protein by 60%-70% in the patient. Quantitative in vivo and in vitro expression studies revealed a ratio of splicing transcript amounts different from those normally seen in controls. Apparently, the reduced expression of the wild-type fragment, which results in the decreased protein expression, rather than the increased amount of aberrant splicing fragments of the HADH2 gene, is pathogenic. Our data therefore strongly suggest that reduced expression of the HADH2 protein causes MRXS10, a phenotype different from that caused by 2-methyl-3-hydroxybutyryl-CoA dehydrogenase deficiency, which is a neurodegenerative disorder caused by missense mutations in this multifunctional protein.

Bayesian imputation of non-chosen attribute values in revealed preference surveys

Obtaining attribute values of non-chosen alternatives in a revealed preference context is challenging because non-chosen alternative attributes are unobserved by choosers, chooser perceptions of attribute values may not reflect reality, existing methods for imputing these values suffer from shortcomings, and obtaining non-chosen attribute values is resource intensive. This paper presents a unique Bayesian (multiple) Imputation Multinomial Logit model that imputes unobserved travel times and distances of non-chosen travel modes based on random draws from the conditional posterior distribution of missing values. The calibrated Bayesian (multiple) Imputation Multinomial Logit model imputes non-chosen time and distance values that convincingly replicate observed choice behavior. Although network skims were used for calibration, more realistic data such as supplemental geographically referenced surveys or stated preference data may be preferred. The model is ideally suited for imputing variation in intrazonal non-chosen mode attributes and for assessing the marginal impacts of travel policies, programs, or prices within traffic analysis zones.

Molecular dynamics simulation of mechanical behavior of osteopontin-hydroxyapatite interfaces

Bone is characterized with an optimized combination of high stiffness and toughness. The understanding of bone nanomechanics is critical to the development of new artificial biological materials with unique properties. In this work, the mechanical characteristics of the interfaces between osteopontin (OPN, a noncollagenous protein in extrafibrillar protein matrix) and hydroxyapatite (HA, a mineral nanoplatelet in mineralized collagen fibrils) were investigated using molecular dynamics method. We found that the interfacial mechanical behaviour is governed by the electrostatic attraction between acidic amino acid residues in OPN and calcium in HA. Higher energy dissipation is associated with the OPN peptides with a higher number of acidic amino acid residues. When loading in the interface direction, new bonds between some acidic residues and HA surface are formed, resulting in a stick-slip type motion of OPN peptide on the HA surface and high interfacial energy dissipation. The formation of new bonds during loading is considered to be a key mechanism responsible for high fracture resistance observed in bone and other biological materials.

Monitoring phase behavior of sub- and supercritical CO2 confined in porous fractal silica with 85% porosity

Phase behavior of CO2 confined in porous fractal silica with volume fraction of SiO2 φs = 0.15 was investigated using small-angle neutron scattering (SANS) and ultrasmall-angle neutron scattering (USANS) techniques. The range of fluid densities (0<(FCO2)bulk<0.977 g/cm3) and temperatures (T=22 °C, 35 and 60 °C) corresponded to gaseous, liquid, near critical and supercritical conditions of the bulk fluid. The results revealed formation of a dense adsorbed phase in small pores with sizes D<40 A° at all temperatures. At low pressure (P <55 bar, (FCO2)bulk <0.2 g/cm3) the average fluid density in pores may exceed the density of bulk fluid by a factor up to 6.5 at T=22 °C. This “enrichment factor” gradually decreases with temperature, however significant fluid densification in small pores still exists at temperature T=60°C, i.e., far above the liquid-gas critical temperature of bulk CO2 (TC=31.1 °C). Larger pores are only partially filled with liquid-like adsorbed layer which coexists with unadsorbed fluid in the pore core. With increasing pressure, all pores become uniformly filled with the fluid, showing no measurable enrichment or depletion of the porous matrix with CO2.

Analysis of strain-rate dependent mechanical behavior of single chondrocyte : a finite element study

Various studies have been conducted to investigate the effects of impact loading on cartilage damage and chondrocyte death. These have shown that the rate and magnitude of the applied strain significantly influence chondrocyte death, and that cell death occurred mostly in the superficial zone of cartilage suggesting the need to further understand the fundamental mechanisms underlying the chondrocytes death induced at certain levels of strain-rate. To date there is no comprehensive study providing insight on this phenomenon. The aim of this study is to examine the strain-rate dependent behavior of a single chondrocyte using a computational approach based on Finite Element Method (FEM). An FEM model was developed using various mechanical models, which were Standard Neo-Hookean Solid (SnHS), porohyperelastic (PHE) and poroviscohyperelastic (PVHE) to simulate Atomic Force Microscopy (AFM) experiments of chondrocyte. The PVHE showed, it can capture both relaxation and loading rate dependent behaviors of chondrocytes, accurately compared to other models.

Trade, travel and disease : the role of law in pandemic preparedness

In 2009 the world experienced an influenza pandemic caused by the H1N1 virus. While the pandemic was milder then expected, it nonetheless provided the world with an opportunity to do real-time testing of pandemic preparedness. This paper examines the threats to human health posed by infectious diseases and the challenges for the global community in development of effective surveillance systems for emerging infectious diseases. In 2005 a new revised version of the International Health Regulations (IHR) was adopted. The requirements of the IHR (2005) are outlined and considered in light of the constraints facing resource-poor countries. Finally, the paper addresses the role of domestic law-making in supporting public health preparedness and articulates a number of ethical principles that should be considered when developing new public health laws.

Benefit of accident reduction considering the improvement of travel time reliability

Traffic accidents often cause lane closure, and diminish stability of travel time as well as the level of road services. On the other hand, research on the implementation of ITS services aiming at the reduction of traffic accidents has made considerable progress lately. However there has been little discussion on the benefits obtained by traffic accident reduction from the view point of travel time reliability. Therefore, in this research, relationships between traffic accidents and travel time reliability are examined, and the benefit of traffic accident reduction is calculated based on the scheduling model under travel time uncertainties. The results show the significance of traffic accident reduction for the improvement of travel time reliability.

Patterns of accelerometer-assessed sedentary behavior in older women

Recent studies suggest a high volume of sedentary behavior may be a risk factor for adverse health outcomes.1 However, few data exist on how this behavior is patterned (eg, does most sedentary behavior occur in a few long bouts or in many short bouts?) and whether sedentary patterns are relevant for health. We examined details of sedentary behavior among older women. Because physical activity is influenced by age, body mass index (BMI; calculated as weight in kilograms divided by height in meters squared), and smoking status, we further examined sedentary behavior in relation to these characteristics.