Model Studies On The Interactions Among Carbon Substrates, Bacteria And Consumers In A Salt-Marsh Estuary

We have developed a lagrangian computer simulation model to investigate the interactions between dissolved and particulate carbon-substrates of detrital (vascular plants) and phytoplankton origin, microbes attached and free-living in the water column, and consumers of these substrates for a specific estuarine water body: the Duplin River, Sapelo Island, Georgia. Model simulation experiments were directed toward investigating the potential for both carbon resource and heterotrophic grazing as controls on free-living and particle-attached bacterial densities. Given available information from the literature and our own work, we present simulations of the model that approximate what one generally finds in this estuary during summer relative to the dynamics of particulate organic carbon (paC), dissolved organic carbon (DOC), free-living bacteria and microconsumers. Predicted dynamics of the bacteria were insensitive to macroconsumer grazing but highly sensitive to the parameter values governing microconsumer grazing rates and metabolism. Within reasonable constraints of the parameter values used, however, we were unable to reduce the predicted densities of particle-attached bacteria by manipulation of either resource (carbon) availability or grazing pressures. We propose several alternate hypotheses that might explain this discrepancy between model results and what is generally reported for natural systems

Ergodic Jacobi matrices and conformal maps

We study structural properties of the Lyapunov exponent $\gamma$ and the density of states $k$ for ergodic (or just invariant) Jacobi matrices in a general framework. In this analysis, a central role is played by the function $w=-\gamma+i\pi k$ as a conformal map between certain domains. This idea goes back to Marchenko and Ostrovskii, who used this device in their analysis of the periodic problem

Assessment of a novel, capsid-modified adenovirus with an improved vascular gene transfer profile

<p>Background: Cardiovascular disorders, including coronary artery bypass graft failure and in-stent restenosis remain significant opportunities for the advancement of novel therapeutics that target neointimal hyperplasia, a characteristic of both pathologies. Gene therapy may provide a successful approach to improve the clinical outcome of these conditions, but would benefit from the development of more efficient vectors for vascular gene delivery. The aim of this study was to assess whether a novel genetically engineered Adenovirus could be utilised to produce enhanced levels of vascular gene expression.</p> <p>Methods: Vascular transduction capacity was assessed in primary human saphenous vein smooth muscle and endothelial cells using vectors expressing the LacZ reporter gene. The therapeutic capacity of the vectors was compared by measuring smooth muscle cell metabolic activity and migration following infection with vectors that over-express the candidate therapeutic gene tissue inhibitor of matrix metalloproteinase-3 (TIMP-3).</p> <p>Results: Compared to Adenovirus serotype 5 (Ad5), the novel vector Ad5T*F35++ demonstrated improved binding and transduction of human vascular cells. Ad5T*F35++ mediated expression of TIMP-3 reduced smooth muscle cell metabolic activity and migration in vitro. We also demonstrated that in human serum samples pre-existing neutralising antibodies to Ad5T*F35++ were less prevalent than Ad5 neutralising antibodies.</p> <p>Conclusions: We have developed a novel vector with improved vascular transduction and improved resistance to human serum neutralisation. This may provide a novel vector platform for human vascular gene transfer.</p&gt

Severe bronchopulmonary dysplasia improved by noninvasive positive pressure ventilation: a case report

<p>Abstract</p> <p>Introduction</p> <p>This is the first report to describe the feasibility and effectiveness of noninvasive positive pressure ventilation in the secondary treatment of bronchopulmonary dysplasia.</p> <p>Case presentation</p> <p>A former male preterm of Caucasian ethnicity delivered at 29 weeks gestation developed severe bronchopulmonary dysplasia. At the age of six months he was in permanent tachypnea and dyspnea and in need of 100% oxygen with a flow of 2.0 L/minute via a nasal cannula. Intermittent nocturnal noninvasive positive pressure ventilation was then administered for seven hours daily. The ventilator was set at a positive end-expiratory pressure of 6 cmH₂O, with pressure support of 4 cmH₂O, trigger at 1.4 mL/second, and a maximum inspiratory time of 0.7 seconds. Over the course of seven weeks, the patient's maximum daytime fraction of inspired oxygen via nasal cannula decreased from 1.0 to 0.75, his respiratory rate from 64 breaths/minute to 50 breaths/minute and carbon dioxide from 58 mmHg to 44 mmHg.</p> <p>Conclusion</p> <p>Noninvasive positive pressure ventilation may be a novel therapeutic option for established severe bronchopulmonary dysplasia. In the case presented, noninvasive positive pressure ventilation achieved sustained improvement in ventilation and thus prepared our patient for safe home oxygen therapy.</p

Doppler findings in a rare Coronary Artery Fistula

One of the primary forms of congenital anomalies of the coronary arteries is coronary artery fistula (CAF). It is defined as a direct communication between the coronary artery and any surrounding cardiac chamber or vascular structure, which bypasses the myocardial capillary bed. We present a newborn baby with a large coronary artery fistula connecting the left anterior descending (LAD) artery to the left ventricular (LV) apex. Associated cardiac abnormalities were found: a ventricular septal defect (diameter 4 mm), a patent foramen ovale as well as trivial tricuspid and mitral regurgitation. Here we demonstrate the echocardiograms of an extremely rare form of CAF diagnosed within the first days of postnatal life

Cooperative coupling of ultracold atoms and surface plasmons

Cooperative coupling between optical emitters and light fields is one of the outstanding goals in quantum technology. It is both fundamentally interesting for the extraordinary radiation properties of the participating emitters and has many potential applications in photonics. While this goal has been achieved using high-finesse optical cavities, cavity-free approaches that are broadband and easy to build have attracted much attention recently. Here we demonstrate cooperative coupling of ultracold atoms with surface plasmons propagating on a plane gold surface. While the atoms are moving towards the surface they are excited by an external laser pulse. Excited surface plasmons are detected via leakage radiation into the substrate of the gold layer. A maximum Purcell factor of $\eta_\mathrm{P}=4.9$ is reached at an optimum distance of $z=250~\mathrm{nm}$ from the surface. The coupling leads to the observation of a Fano-like resonance in the spectrum.Comment: 9 pages, 4 figure

Hierarchy measure for complex networks

Nature, technology and society are full of complexity arising from the intricate web of the interactions among the units of the related systems (e.g., proteins, computers, people). Consequently, one of the most successful recent approaches to capturing the fundamental features of the structure and dynamics of complex systems has been the investigation of the networks associated with the above units (nodes) together with their relations (edges). Most complex systems have an inherently hierarchical organization and, correspondingly, the networks behind them also exhibit hierarchical features. Indeed, several papers have been devoted to describing this essential aspect of networks, however, without resulting in a widely accepted, converging concept concerning the quantitative characterization of the level of their hierarchy. Here we develop an approach and propose a quantity (measure) which is simple enough to be widely applicable, reveals a number of universal features of the organization of real-world networks and, as we demonstrate, is capable of capturing the essential features of the structure and the degree of hierarchy in a complex network. The measure we introduce is based on a generalization of the m-reach centrality, which we first extend to directed/partially directed graphs. Then, we define the global reaching centrality (GRC), which is the difference between the maximum and the average value of the generalized reach centralities over the network. We investigate the behavior of the GRC considering both a synthetic model with an adjustable level of hierarchy and real networks. Results for real networks show that our hierarchy measure is related to the controllability of the given system. We also propose a visualization procedure for large complex networks that can be used to obtain an overall qualitative picture about the nature of their hierarchical structure.Comment: 29 pages, 9 figures, 4 table

Lessons learned from the AFLY5 RCT process evaluation: Implications for the design of physical activity and nutrition interventions in schools Health behavior, health promotion and society

© 2015 Jago et al. Background: Systematic reviews have highlighted that school-based diet and physical activity (PA) interventions have had limited effects. This study used qualitative methods to examine how the effectiveness of future primary (elementary) school diet and PA interventions could be improved. Methods: Data are from the Active For Life Year 5 (AFLY5) study, which was a cluster randomised trial conducted in 60 UK primary schools. Year 5 (8-9 years of age) pupils in the 30 intervention schools received a 12-month intervention. At the end of the intervention period, interviews were conducted with: 28 Year 5 teachers (including 8 teachers from control schools); 10 Headteachers (6 control); 31 parents (15 control). Focus groups were conducted with 70 year 5 pupils (34 control). Topics included how the AFLY5 intervention could have been improved and how school-based diet and PA interventions should optimally be delivered. All interviews and focus groups were transcribed and thematically analysed across participant groups. Results: Analysis yielded four themes. Child engagement: Data suggested that programme success is likely to be enhanced if children feel that they have a sense of autonomy over their own behaviour and if the activities are practical. School: Finding a project champion within the school would enhance intervention effectiveness. Embedding diet and physical activity content across the curriculum and encouraging teachers to role model good diet and physical activity behaviours were seen as important. Parents and community: Encouraging parents and community members into the school was deemed likely to enhance the connection between schools, families and communities, and "create a buzz" that was likely to enhance behaviour change. Government/Policy: Data suggested that there was a need to adequately resource health promotion activity in schools and to increase the infrastructure to facilitate diet and physical activity knowledge and practice. Discussion and Conclusions: Future primary school diet and PA programmes should find ways to increase child engagement in the programme content, identify programme champions, encourage teachers to work as role models, engage parents and embed diet and PA behaviour change across the curriculum. However, this will require adequate funding and cost-effectiveness will need to be established. Trial registration: ISRCTN5013374

Bayesian Fit of Exclusive b→sℓˉℓb \to s \bar\ell\ell Decays: The Standard Model Operator Basis

We perform a model-independent fit of the short-distance couplings $C_{7,9,10}$ within the Standard Model set of $b\to s\gamma$ and $b\to s\bar\ell\ell$ operators. Our analysis of $B \to K^* \gamma$, $B \to K^{(*)} \bar\ell\ell$ and $B_s \to \bar\mu\mu$ decays is the first to harness the full power of the Bayesian approach: all major sources of theory uncertainty explicitly enter as nuisance parameters. Exploiting the latest measurements, the fit reveals a flipped-sign solution in addition to a Standard-Model-like solution for the couplings $C_i$. Each solution contains about half of the posterior probability, and both have nearly equal goodness of fit. The Standard Model prediction is close to the best-fit point. No New Physics contributions are necessary to describe the current data. Benefitting from the improved posterior knowledge of the nuisance parameters, we predict ranges for currently unmeasured, optimized observables in the angular distributions of $B\to K^*(\to K\pi)\,\bar\ell\ell$.Comment: 42 pages, 8 figures; v2: Using new lattice input for f_Bs, considering Bs-mixing effects in BR[B_s->ll]. Main results and conclusion unchanged, matches journal versio