The Egyptian Cardiothoracic Surgeon (ECTS - E-Journal)
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Using web mining to explore Triple Helix influences on growth in small crossmark and mid-size firms
No full textWhile broad Triple Helix frameworks of industry, government and university collaborations have the potential to enhance innovation and economic development at macro-levels, at the micro-level of the firm it should not be assumed that such relationships are uniform in character or outcomes. Each firm will negotiate and develop its own set of relationships with other innovation system actors based on its capabilities and strategies. To better understand these dynamics, particularly from the perspective of small and medium-sized enterprises, this study probes the micro-level characteristics and impacts of external enterprise relationships. Novel website-based Triple Helix measures are introduced that extend the analytical scope beyond customary indicators (such as patent analysis or entropy measures) to include communication and coordination among all three helices at the micro-level of individual firms. This approach is used to explore the micro-level characteristics and impacts of industry, government and university relations for small and medium-sized enterprises by analyzing a subset of more than 270 U.S. green goods small and medium-sized manufacturing enterprises. We compare the website-based measures with case study results to authenticate the method. A panel data regression model is then employed to analyze the simultaneous impacts of various combinations of industry, government and university links on firm sales growth (2008-2011), with controls for region, scale, and application domains. The ability of website-based indicators to distinguish the impacts of different mixes of Triple Helix relations is demonstrated. The results show that relationships with all three helices have a positive total marginal effect on firm sales growth, although enterprise relationships with just one or two Triple Helix actors have mixed growth effects. The implications of these findings are discussed
Past management of energy demand: promotion and adoption of electric heating in Britain 1945-64
No full textChanges in energy use have been a key part of many dramatic social, economic and environmental changes during the twentieth century and before, making energy interesting to environmental historians. Today, policy makers seek reductions in energy use and carbon emissions to mitigate climate change through demand management policies that attempt to reduce usage or shift it in time away from peak demand. To understand the impact of such policies it is necessary to understand both how they were promoted and received. This article discusses electric heating in early post-war Britain, which was seen as a particularly problematic energy use, as electric fires were used at peak times. The Electricity Development Association (EDA) tried simultaneously to reduce undesirable peak demand while encouraging increased demand more generally. In the late 1940s it advertised against peak use of electric fires, whereas in the 1950s and 1960s it instead concentrated on promoting off-peak heating appliances, first under-floor heating and then block storage heaters. I will analyse how the London County Council and its tenants adopted and adapted electric underfloor heating, illustrating the complicated way demand is made and unmade. The paper concludes that, while demand management has been attempted by the electricity industry since well before the 1970s, these attempts only had a limited effect on the overall trend towards increasing demand, in part to do with how these promotions were adopted
The anterior temporal cortex is the primary semantic source of top-down influences on object recognition.
No full textPerception emerges from a dynamic interplay between feed-forward sensory input and feedback modulation along the cascade of neural processing. Prior knowledge, a major form of top-down modulatory signal, benefits perception by enabling efficacious inference and resolving ambiguity, particularly under circumstances of degraded visual input. Despite semantic information being a potentially critical source of this top-down influence, to date, the core neural substrate of semantic knowledge (the anterolateral temporal lobe – ATL) has not been considered as a key component of the feedback system. Here we provide direct evidence of its significance for visual cognition – the ATL underpins the semantic aspect of object recognition, amalgamating sensory-based (amount of accumulated sensory input) and semantic-based (representational proximity between exemplars and typicality of appearance) influences. Using transcranial theta-burst stimulation combined with a novel visual identification paradigm, we demonstrate that the left ATL contributes to discrimination between visual objects. Crucially, its contribution is especially vital under situations where semantic knowledge is most needed for supplementing deficiency of input (brief visual exposure), discerning analogously-coded exemplars (close representational distance), and resolving discordance (target appearance violating the statistical typicality of its category). Our findings characterise functional properties of the ATL in object recognition: this neural structure is summoned to augment the visual system when the latter is overtaxed by challenging conditions (insufficient input, overlapped neural coding, and conflict between incoming signal and expected configuration). This suggests a need to revisit current theories of object recognition, incorporating the ATL that interfaces high-level vision with semantic knowledge
Adsorption Properties of MFM-400 and MFM-401 with CO2 and Hydrocarbons: Selectivity Derived from Directed Supramolecular Interactions
No full text([Sc2(OH)2(BPTC)]) (H4BPTC = biphenyl-3,3′,5,5′-tetracarboxylic acid), MFM-400 (MFM = Manchester Framework Material, previously designated NOTT), and ([Sc(OH)(TDA)]) (H2TDA = thiophene-2,5-dicarboxylic acid), MFM-401, both show selective and reversible capture of CO2. In particular, MFM-400 exhibits a reasonably high CO2 uptake at low pressures and competitive CO2/N2 selectivity coupled to a moderate isosteric heat of adsorption (Qst) for CO2 (29.5 kJ mol–1) at zero coverage, thus affording a facile uptake–release process. Grand canonical Monte Carlo (GCMC) and density functional theory (DFT) computational analyses of CO2 uptake in both materials confirmed preferential adsorption sites consistent with the higher CO2 uptake observed experimentally for MFM-400 over MFM-401 at low pressures. For MFM-400, the Sc–OH group participates in moderate interactions with CO2 (Qst = 33.5 kJ mol–1), and these are complemented by weak hydrogen-bonding interactions (O···H–C = 3.10–3.22 Å) from four surrounding aromatic −CH groups. In the case of MFM-401, adsorption is provided by cooperative interactions of CO2 with the Sc–OH group and one C–H group. The binding energies obtained by DFT analysis for the adsorption sites for both materials correlate well with the observed moderate isosteric heats of adsorption for CO2. GCMC simulations for both materials confirmed higher uptake of EtOH compared with nonpolar vapors of toluene and cyclohexane. This is in good correlation with the experimental data, and DFT analysis confirmed the formation of a strong hydrogen bond between EtOH and the hydrogen atom of the hydroxyl group of the MFM-400 and MFM-401 framework (FW) with H–OEtOH···H–OFW distances of 1.77 and 1.75 Å, respectively. In addition, the accessible regeneration of MFM-400 and MFM-401 and release of CO2 potentially provide minimal economic and environmental penalties
Characterisation of Neopeptides in Equine Articular Cartilage Degradation
No full textOsteoarthritis is characterized by a loss of extracellular matrix which leads to cartilage degradation and joint space narrowing. Specific proteases including the aggrecanases ADAMTS-4 and matrix metalloproteinase 3 are important in initiating and promoting cartilage degradation in osteoarthritis. This study investigated protease specific and disease specific cleavage patterns of particular extracellular matrix proteins by comparing new peptide fragments; neopeptides, in specific exogenous protease driven digestion of a crude cartilage proteoglycan extract and an in-vitro model of early osteoarthritis. Additionally equine cartilage explants were treated with interleukin-1 and the media collected. Proteolytic cleavage products following trypsin digestion were then identified using tandem mass spectrometry. Complete sequences of proteolytically cleaved neopeptides were determined for the major cartilage proteoglycans aggrecan, biglycan, decorin, fibromodulin plus cartilage oligomeric matrix protein. The generation of neopeptides varied with enzyme specificity; however some peptides were common to all samples. Previous known and novel cleavage sites were identifies. The identification of novel peptide fragments provides a platform for the development of antibodies which could assist in the identification of biomarkers for OA, as well as identifying basic biochemical processes underlying OA
Changes in Arterial Access Site and Association With Mortality in the United Kingdom: Observations From a National Percutaneous Coronary Intervention Database.
No full textBACKGROUND: -The transradial access (TRA) site has become the default access site for PCI in the UK with randomized trials and national registry data showing reductions in mortality associated with TRA utilization. This study evaluates regional changes in access site practice in England and Wales over time and whether changes in access site practice has been uniform nationally and across different patient sub-groups, and provide national estimates for the potential number of lives 'saved' or 'lost' associated with regional differences in access site practice. METHODS AND RESULTS: -Using the BCIS (British Cardiovascular Intervention Society) database, we investigated outcomes for growth of TRA in different regions in England and Wales in 448,853 patients who underwent PCI, 2005-2012. Multiple logistic regressions used to quantify the effect of TRA on 30-day mortality and quantify lives 'saved' and 'lost' by differences in TRA adoption. TRA utilization increased from 14.0% to 58.6% in 417,038 PCI patients with large variations in different parts of the country. TRA was independently associated with a decreased risk of 30-day mortality (OR=0.70; 95%CI=0.66-0.74) with significant but small differences observed across different regions. The number of estimated lives 'saved' was 450 (95%CI=275-650) and estimate that an additional 264 (95%CI=153-399) lives would have been saved if TRA adoption were uniform nationally. CONCLUSIONS: -TRA has become the dominant PCI approach in the UK with a wide variation in different parts of the country. Changes in practice have contributed to mortality reductions, whilst inequalities have resulted in missed opportunities for further improvements
Sensitivity to Change of Patient-Preference Measures for Pain in Trials of Patients with Knee Osteoarthritis: Data from Two Trials
No full textObjectiveIn osteoarthritis (OA) clinical trials, a pain measure that is most sensitive to change is considered optimal. We compared sensitivity to change of patient-reported pain outcomes, including a patient-preference measure (where the patient nominates an activity that aggravates their pain).MethodsWe used data from 2 trials of patients with confirmed (American College of Rheumatology criteria) knee OA: a trial of brace treatment for patellofemoral OA, and a trial of intraarticular steroids in knee OA. Both trials reported an improvement in pain following treatment. Participants rated pain on a 100-mm visual analog scale (VAS), in the activity that caused them the most knee pain (VASNA), as well as completing questions on overall knee pain and the Knee Injury and Osteoarthritis Outcome Score (KOOS) questionnaire. Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores were also calculated from the KOOS. Standardized changes in each outcome were generated between treatment and control after 6 weeks intervention in the BRACE trial, and 1–2 weeks following intervention in the steroid trial.ResultsThe VASNA produced standardized changes following treatment that were at least as large as other pain outcomes. In the BRACE trial, the between-groups standardized change with the VASNA was −0.63, compared with the KOOS pain subscale change of −0.33, and pain in the last week VAS change of −0.56. In the steroid study, within-group change following treatment in the VASNA was −0.60, compared to the last week VAS change of −0.51, and KOOS pain subscale change of −0.58.ConclusionPain on nominated activity appears to be at least as, and in some cases more, sensitive to change than the KOOS/WOMAC questionnaire
Incidence and natural history of hen's egg allergy in the first 2 years of life-the EuroPrevall birth cohort study.
No full textBACKGROUND: Parents and health staff perceive hen's egg allergy (HEA) as a common food allergy in early childhood, but the true incidence is unclear because population-based studies with gold-standard diagnostic criteria are lacking. OBJECTIVE: To establish the incidence and course of challenge-confirmed HEA in children, from birth until the age of 24 months, in different European regions. METHODS: In the EuroPrevall birth cohort study, children with a suspected HEA and their age-matched controls were evaluated in 9 countries, using a standardized protocol including measurement of HE-specific immunoglobulin E-antibodies in serum, skin prick tests, and double-blind, placebo-controlled food challenges (DBPCFC). RESULTS: Across Europe, 12 049 newborns were enrolled, and 9336 (77.5%) were followed up to 2 years of age. In 298 children, HEA was suspected and DBPCFC was offered. HEA by age two was confirmed in 86 of 172 challenged children (mean raw incidence 0.84%, 95% confidence interval (95% CI) 0.67-1.03). Adjusted mean incidence of HEA was 1.23% (95% CI 0.98-1.51) considering possible cases among eligible children who were not challenged. Centre-specific incidence ranged from United Kingdom (2.18%, 95% CI 1.27-3.47) to Greece (0.07%). Half of the HE-allergic children became tolerant to HE within 1 year after the initial diagnosis. CONCLUSIONS: The largest multinational European birth cohort study on food allergy with gold-standard diagnostic methods showed that the mean adjusted incidence of HEA was considerably lower than previously documented, although differences in incidence rates among countries were noted. Half of the children with documented HEA gained tolerance within 1 year postdiagnosis
