Not so social media: Twitter use in the conference sector

This research forms part of a larger project funded by Meeting Professionals International (MPI) focusing on the future of business events . In this paper we investigate the motivations for social media use within a professional event context. Twitter was tracked before during and after seven conferences and from this the top tweeters and organisers were identified. Fifteen interviews were conducted into both the organisational strategy and individual motivations for tweeting and were analysed alongside interviews with five social media experts. The research highlights several potential areas of conflict. Social media use tends to focus on broadcasting information rather than encouraging dialogue. People only tweet if they gain personal or individual professional value from doing so and event organisers need a deeper understanding of what that value is. Monitoring social media to gain customer insights and develop a more responsive customer service strategy is not yet happening although it is recognised as a necessity. The silent majority (passives) need to be better understood and catered for through social media use. Overall this sector, which successfully creates social interactions offline appears to be failing to do so online. A more strategic and resourced approach to social media is needed if its potential is to be achieved

Wellbeing at the edges of ownership

The test of a well-functioning housing system is the wellbeing of its occupants. It may therefore seem encouraging that in jurisdictions dominated by mortgage-backed home ownership, owner-occupiers traditionally report better physical and mental health than renters. During the 2000s, however, in an era of financial crisis, wellbeing at the edges of ownership came under strain. Using data from two national panel surveys – the survey of Household, Income and Labour Dynamics in Australia, and the British Household Panel Survey (with its successor, Understanding Society) – we track the wellbeing of households who sustained one or more spells of home ownership in the decade to 2010. We estimate log-log regression models of mental wellbeing for each country, documenting (with an appropriate range of controls) the effects of both tenure transitions (between ownership and renting) and some associated financial transactions (anchored on mortgage debt). We find: a wellbeing premium associated with outright ownership and a debt-effect among mortgagors; a wellbeing deficit among those who drop out of owner-occupation, with partial recovery where exit is enduring; and for leavers especially, a wellbeing cost to equity borrowing. Cross-national differences have an institutional explanation, but similarities relating to the character and regulation of mortgage markets are more striking.This work was supported by the Australian Housing and Urban Research Institute (AHURI) under grant number 53011. The HILDA project was funded by the Australian Government Department of Social Services (DSS)

Longer-term increased cortisol levels in young people with mental health problems.

Disturbance of hypothalamus-pituitary-adrenal axis activity is commonly reported in a range of mental disorders in blood, saliva and urine samples. This study aimed to look at longer-term cortisol levels and their association with clinical symptoms. Hair strands of 30 young people (16-25 years) presenting with mental health problems (Mage±SD=21±2.4, 26 females) and 28 healthy controls (HC, Mage±SD=20±2.9, 26 females) were analyzed for cortisol concentrations, representing the past 6 months prior to hair sampling. Clinical participants completed an assessment on psychiatric symptoms, functioning and lifestyle factors. All participants completed the Perceived Stress Scale. Hair cortisol concentrations representing the past 3 (but not 3-6) months were significantly increased in clinical participants compared to HC. Perceived stress in the past month was significantly higher in clinical participants compared to HC, but not significantly correlated with hair cortisol. Hair cortisol levels were not significantly associated with any other measures. Hair segment analyses revealed longer-term increased levels of cortisol in the past 3 months in early mental health problems. Further insight into the role of cortisol on the pathogenesis of mental illnesses requires longitudinal studies relating cortisol to psychopathology and progression of illness

Aiming to Deceive: Examining the Role of the Quiet Eye During Deceptive Aiming Actions

This is the author accepted manuscript. The final version is available from Human Kinetics via the DOI in this record.In three experiments, we explored the use of deceptive gaze in soccer penalty takers using eye-tracking equipment. In Experiment 1, players competed against a goalkeeper while taking unconstrained shots. Results indicated that when players used deception (looking to the opposite side to which they shot), they extended the duration of their final aiming (quiet eye) fixation and maintained shooting accuracy. In Experiment 2, with no goalkeeper present, players still used extended quiet-eye durations when using a deceptive strategy, but this time, their accuracy suffered. In Experiment 3, we manipulated the goalkeeper's location while controlling for the use of peripheral vision and memory of goal size. Results indicated that increased quiet-eye durations were required when using deceptive aiming, and that accuracy was influenced by the position of the goalkeeper. We conclude that during deceptive aiming, soccer players maintain accuracy by covertly processing information related to the goalkeeper's location

Structure-property-function relationships in triple helical collagen hydrogels

In order to establish defined biomimetic systems, type I collagen was functionalised with 1,3-Phenylenediacetic acid (Ph) as aromatic, bifunctional segment. Following investigation on molecular organization and macroscopic properties, material functionalities, i.e. degradability and bioactivity, were addressed, aiming at elucidating the potential of this collagen system as mineralization template. Functionalised collagen hydrogels demonstrated a preserved triple helix conformation. Decreased swelling ratio and increased thermo-mechanical properties were observed in comparison to state-of-the-art carbodiimide (EDC)-crosslinked collagen controls. Ph-crosslinked samples displayed no optical damage and only a slight mass decrease (∼ 4 wt.-%) following 1-week incubation in simulated body fluid (SBF), while nearly 50 wt.-% degradation was observed in EDC-crosslinked collagen. SEM/EDS revealed amorphous mineral deposition, whereby increased calcium phosphate ratio was suggested in hydrogels with increased Ph content. This investigation provides valuable insights for the synthesis of triple helical collagen materials with enhanced macroscopic properties and controlled degradation. In light of these features, this system will be applied for the design of tissue-like scaffolds for mineralized tissue formation

In-situ crosslinked wet spun collagen triple helices with nanoscale-regulated ciprofloxacin release capability

The design of antibacterial-releasing coatings or wrapping materials with controlled drug release capability is a promising strategy to minimise risks of infection and medical device failure in vivo. Collagen fibres have been employed as medical device building block, although they still fail to display controlled release capability, competitive wet-state mechanical properties, and retained triple helix organisation. We investigated this challenge by pursuing a multiscale design approach integrating drug encapsulation, in-situ covalent crosslinking and fibre spinning. By selecting ciprofloxacin (Cip) as a typical antibacterial drug, wet spinning was selected as a triple helix-friendly route towards Cip-encapsulated collagen fibres; whilst in–situ crosslinking of fibre-forming triple helices with 1,3–phenylenediacetic acid (Ph) was hypothesised to yield Ph-Cip π-π stacking aromatic interactions and enable controlled drug release. Higher tensile modulus and strength were measured in Ph–crosslinked fibres compared to state-of-the-art carbodiimide–crosslinked controls. Cip-encapsulated Ph-crosslinked fibres revealed decreased elongation at break and significantly-enhanced drug retention in vitro with respect to Cip-free variants and carbodiimide-crosslinked controls, respectively. This multiscale manufacturing strategy provides new insight aiming at wet spun collagen triple helices with nanoscale-regulated tensile properties and drug release capability

Influence of 4-vinylbenzylation on the rheological and swelling properties of photo activated collagen hydrogels

Covalent functionalisation of collagen has been shown to be a promising strategy to adjust the mechanical properties of highly swollen collagen hydrogels. At the same time, secondary interactions between for example, amino acidic terminations or introduced functional groups also play an important role and are often challenging to predict and control. To explore this challenge, 4-vinylbenzyl chloride (4VBC) and methacrylic anhydride (MA) were reacted with type I collagen, and the swelling and rheological properties of resulting photo-activated hydrogel systems investigated. 4VBC-based hydrogels showed significantly increased swelling ratio, in light of the lower degree of collagen functionalisation, with respect to methacrylated collagen networks, whilst rheological storage moduli were found to be comparable between the two systems. To explore the role of benzyl groups in the mechanical properties of the 4VBC-based collagen system, model chemical force microscopy (CFM) was carried out in aqueous environment with an aromatised probe against an aromatised gold-coated glass slide. A marked increase in adhesion force (F: 0.11±0.01 nN) was measured between aromatised samples, compared to the adhesion force observed between the non-modified probe and a glass substrate (F: 2.64±1.82 nN). These results suggest the formation of additional and reversible π-π stacking interactions in aromatic 4VBC-based networks and explain the remarkable rheological properties of this system in comparison to MA-based hydrogels

Biomimetic wet-stable fibres via wet spinning and diacid-based crosslinking of collagen triple helices

One of the limitations of electrospun collagen as bone-like fibrous structure is the potential collagen triple helix denaturation in the fibre state and the corresponding inadequate wet stability even after crosslinking. Here, we have demonstrated the feasibility of accomplishing wet-stable fibres by wet spinning and diacid-based crosslinking of collagen triple helices, whereby fibre ability to act as bone-mimicking mineralisation system has also been explored. Circular dichroism (CD) demonstrated nearly complete triple helix retention in resulting wetspun fibres, and the corresponding chemically crosslinked fibres successfully preserved their fibrous morphology following 1-week incubation in phosphate buffer solution (PBS). The presented novel diacid-based crosslinking route imparted superior tensile modulus and strength to the resulting fibres indicating that covalent functionalization of distant collagen molecules is unlikely to be accomplished by current state-of-the-art carbodiimide-based crosslinking. To mimic the constituents of natural bone extra cellular matrix (ECM), the crosslinked fibres were coated with carbonated hydroxyapatite (CHA) through biomimetic precipitation, resulting in an attractive biomaterial for guided bone regeneration (GBR), e.g. in bony defects of the maxillofacial region

Compositional and in Vitro Evaluation of Nonwoven Type I Collagen/Poly-dl-lactic Acid Scaffolds for Bone Regeneration

Poly-dl-lactic acid (PDLLA) was blended with type I collagen to attempt to overcome the instantaneous gelation of electrospun collagen scaffolds in biological environments. Scaffolds based on blends of type I collagen and PDLLA were investigated for material stability in cell culture conditions (37 °C; 5% CO2) in which post-electrospinning glutaraldehyde crosslinking was also applied. The resulting wet-stable webs were cultured with bone marrow stromal cells (HBMSC) for five weeks. Scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM), Fourier transform infra-red spectroscopy (FTIR) and biochemical assays were used to characterise the scaffolds and the consequent cell-scaffold constructs. To investigate any electrospinning-induced denaturation of collagen, identical PDLLA/collagen and PDLLA/gelatine blends were electrospun and their potential to promote osteogenic differentiation investigated. PDLLA/collagen blends with w/w ratios of 40/60, 60/40 and 80/20 resulted in satisfactory wet stabilities in a humid environment, although chemical crosslinking was essential to ensure long term material cell culture. Scaffolds of PDLLA/collagen at a 60:40 weight ratio provided the greatest stability over a five-week culture period. The PDLLA/collagen scaffolds promoted greater cell proliferation and osteogenic differentiation compared to HMBSCs seeded on the corresponding PDLLA/gelatine scaffolds, suggesting that any electrospinning-induced collagen denaturation did not affect material biofunctionality within 5 weeks in vitro

Tuberculosis in a South African prison – a transmission modelling analysis

Background. Prisons are recognised internationally as institutions with very high tuberculosis (TB) burdens where transmission is predominantly determined by contact between infectious and susceptible prisoners. A recent South African court case described the conditions under which prisoners awaiting trial were kept. With the use of these data, a   mathematical model was developed to explore the interactions between incarceration conditions and TB control measures.Methods. Cell dimensions, cell occupancy, lock-up time, TB incidence and treatment delays were derived from court evidence and judicial reports. Using the Wells-Riley equation and probability analyses of contact between prisoners, we estimated the current TB transmission probability within prison cells, and estimated transmission probabilities of improved levels of case finding in combination with implementation of national and  international minimum standards for incarceration.Results. Levels of overcrowding (230%) in communal cells and poor TB case finding result in annual TB transmission risks of 90% per annum. Implementing current national or international cell occupancy  recommendations would reduce TB transmission probabilities by 30% and 50%, respectively. Improved passive case finding, modest ventilation increase or decreased lock-up time would minimally impact on transmission if introduced individually. However, active case finding together with implementation of minimum national and international standards of incarceration could reduce transmission by 50% and 94%, respectively.Conclusions. Current  conditions of detention for awaiting trial prisoners are highly conducive for spread of drug-sensitive and drug-resistant TB. Combinations of simple well-established scientific control measures should be implemented urgently.S Afr Med J 2011;101:809-813