286 research outputs found
Recommended from our members
Sense and Immunity: Context-Dependent Neuro-Immune Interplay
The sensory nervous and immune systems, historically considered autonomous, actually work in concert to promote host defense and tissue homeostasis. These systems interact with each other through a common language of cell surface G protein-coupled receptors and receptor tyrosine kinases as well as cytokines, growth factors, and neuropeptides. While this bidirectional communication is adaptive in many settings, helping protect from danger, it can also become maladaptive and contribute to disease pathophysiology. The fundamental logic of how, where, and when sensory neurons and immune cells contribute to either health or disease remains, however, unclear. Our lab and others’ have begun to explore how this neuro-immune reciprocal dialog contributes to physiological and pathological immune responses and sensory disorders. The cumulative results collected so far indicate that there is an important role for nociceptors (noxious stimulus detecting sensory neurons) in driving immune responses, but that this is highly context dependent. To illustrate this concept, we present our findings in a model of airway inflammation, in which nociceptors seem to have major involvement in type 2 but not type 1 adaptive immunity
Random planar graphs and the London street network
In this paper we analyse the street network of London both in its primary and
dual representation. To understand its properties, we consider three idealised
models based on a grid, a static random planar graph and a growing random
planar graph. Comparing the models and the street network, we find that the
streets of London form a self-organising system whose growth is characterised
by a strict interaction between the metrical and informational space. In
particular, a principle of least effort appears to create a balance between the
physical and the mental effort required to navigate the city
Rich methane laminar flames doped with light unsaturated hydrocarbons. Part II: 1,3butadiene
In line with the study presented in the part I of this paper, the structure
of a laminar rich premixed methane flame doped with 1,3-butadiene has been
investigated. The flame contains 20.7% (molar) of methane, 31.4% of oxygen and
3.3% of 1,3-butadiene, corresponding to an equivalence ratio of 1.8, and a
ratio C4H6 / CH4 of 16 %. The flame has been stabilized on a burner at a
pressure of 6.7 kPa using argon as dilutant, with a gas velocity at the burner
of 36 cm/s at 333 K. The temperature ranged from 600 K close to the burner up
to 2150 K. Quantified species included usual methane C0-C2 combustion products
and 1,3-butadiene, but also propyne, allene, propene, propane, 1,2-butadiene,
butynes, vinylacetylene, diacetylene, 1,3-pentadiene, 2-methyl-1,3-butadiene
(isoprene), 1-pentene, 3-methyl-1-butene, benzene and toluene. In order to
model these new results, some improvements have been made to a mechanism
previously developed in our laboratory for the reactions of C3-C4 unsaturated
hydrocarbons. The main reaction pathways of consumption of 1,3-butadiene and of
formation of C6 aromatic species have been derived from flow rate analyses. In
this case, the C4 route to benzene formation plays an important role in
comparison to the C3 pathway
Looking backward, looking forward: the city region of the mid-21st century
Emerging as a serious tool of analysis in the United States around 1950, the city region concept was increasingly applied in a European context after 1980. Since 2000, it has evolved further with recognition of the polycentric mega-city region, first recognised in Eastern Asia but now seen as an emerging urban form both in Europe and the United States. The paper speculates on the main changes that may impact on the growth and development of such complex urban regions in the first half of the 21st century, concluding that achieving the goal of polycentric urban development may prove more complex than at first it may seem
Reflections on the innovative city : examining three innovative locations in a knowledge bases framework
Abstract
This paper combines three location-based cases with literature background focusing on knowledge bases and cities. The paper considers the regional context of the city of Helsinki and its surrounding area (HMA). Analyzed cases include three specific locations highlighting urban form, connectivity and knowledge-intensive production. Conceptually innovative cities are experiencing extensive change as they transform and change in order to become competitive providers of first class living for highly skilled global work-force. The integration of spatial characteristics into analyses of knowledge intensiveness of cities brings forth new theoretical openings for urban analysis setting platforms for open innovation and economy. The paper focuses on extensive material resources collected in numerous projects. The data gives more reliable picture of the knowledge-intensive locations compared to single interviews or survey studies. The total data includes work and education statistics, stakeholder interviews and observation field work. Provided reflections are classified according to key issues presented in urban studies and economic geography
Kinetics of the hydrogen abstraction ·C2H5 + alkane → C2H6 + alkyl reaction class: an application of the reaction class transition state theory
This paper presents an application of the reaction class transition state theory (RC-TST) to predict thermal rate constants for hydrogen abstraction reactions at alkane by the C2H5 radical on-the-fly. The linear energy relationship (LER), developed for acyclic alkanes, was also proven to hold for cyclic alkanes. We have derived all RCTST
parameters from rate constants of 19 representative
reactions, coupling with LER and the barrier height
grouping (BHG) approach. Both the RC-TST/LER, where
only reaction energy is needed, and the RC-TST/BHG,
where no other information is needed, can predict rate
constants for any reaction in this reaction class with satisfactory accuracy for combustion modeling. Our analysis indicates that less than 50% systematic errors on the average exist in the predicted rate constants using either
the RC-TST/LER or RC-TST/BHG method, while in comparison with explicit rate calculations, the differences
are within a factor of 2 on the average. The results also
show that the RC-TST method is not sensitive to the choice
of density functional theory used
Silencing Nociceptor Neurons Reduces Allergic Airway Inflammation
Lung nociceptors initiate cough and bronchoconstriction. To elucidate if these fibers also contribute to allergic airway inflammation, we stimulated lung nociceptors with capsaicin and observed increased neuropeptide release and immune cell infiltration. In contrast, ablating Nav1.8(+) sensory neurons or silencing them with QX-314, a charged sodium channel inhibitor that enters via large-pore ion channels to specifically block nociceptors, substantially reduced ovalbumin- or house-dust-mite-induced airway inflammation and bronchial hyperresponsiveness. We also discovered that IL-5, a cytokine produced by activated immune cells, acts directly on nociceptors to induce the release of vasoactive intestinal peptide (VIP). VIP then stimulates CD4(+) and resident innate lymphoid type 2 cells, creating an inflammatory signaling loop that promotes allergic inflammation. Our results indicate that nociceptors amplify pathological adaptive immune responses and that silencing these neurons with QX-314 interrupts this neuro-immune interplay, revealing a potential new therapeutic strategy for asthma
Analysing the present: drawing on the legacy of Vere Foster in public policy debate on futures of schools
This paper sets out a framing analysis for a public policy debate on the future of schools that resonates with practitioners in teaching and teacher education on the island of Ireland, north and south, but also in other countries. This is informed by a democratic impulse to facilitate public policy debates, particularly on the ways schools and higher education institutions are directed and constrained by budget cuts and the shrinking of public funding in this age of austerity and gross inequalities. This is also informed by a need for policy learning about global neoliberal agendas, free-market capitalism and its push towards profit-making schools in systems that are deregulated but experience tighter centralized control, which can result in the domination and control of teachers’ work by politicians, corporate-funded think-tanks, entrepreneurs and business managers. Even though Ireland boasts checks and balances in the form of current structures and education legislation in both jurisdictions, the global financial crisis and the collapse of the ‘Celtic Tiger’ together with the ‘troika’ bail-out and Ireland’s exit from the troika in tandem with the unravelling of the common economic model built up over the last three decades have troubled the constituent social and political settlements with regard to teaching and teacher education. The authors also take inspiration from Vere Foster (1819–1900), an Anglo-Irish gentleman, philanthropist and ‘social worker’ with the poor in post-famine Ireland, as well as a significant social campaigner renowned for his contribution to emigration and education. His ideas, generated at a time of great social upheaval, can be reworked to be appropriate in the Ireland of today to address the neoliberal agenda that has brought the Republic of Ireland economy to the brink of disaster. It is argued that imaginative responses about future possibilities for teaching and teacher education, their form, regulation and accountability are but a few of the terms needed for public policy debate that engages the profession on the type of schooling that would best meet the needs of Irish society now and into the future
- …