567 research outputs found
Does certification work in emerging markets? evidence from the Indian IPO market
There is inconclusive evidence regarding the economic value of certification in the context of IPOs in developed markets. Using a natural experiment of regulator mandated IPO grading requirement, we examine the effects of third-party certification in the Indian IPO market. We summarize our empirical results below. First, underpricing is unaffected by the grading process. Second, stock price informativeness as proxied by idiosyncratic volatility increases significantly due to IPO grading process. Third, retail and institutional subscription levels are significantly positively associated with IPO grades after controlling for other certification mechanisms such as underwriter reputation, group affiliation, analyst recommendation and venture capital backing. Finally, using a pseudo grading process we conclude that IPO grades are not mechanically derivable from publicly available information. In a nutshell, we use our unique setting to examine the usefulness of certification in emerging markets with institutional voids
Transformation of a shoaling undular bore
We consider the propagation of a shallow-water undular bore over a gentle monotonic bottom slope connecting two regions of constant depth, in the framework of the variable-coefficient Korteweg-de Vries equation. We show that, when the undular bore advances in the direction of decreasing depth, its interaction with the slowly varying topography results, apart from an adiabatic deformation of the bore itself, in the generation of a sequence of isolated solitons - an expanding large-amplitude modulated solitary wavetrain propagating ahead of the bore. Using nonlinear modulation theory we construct an asymptotic solution describing the formation and evolution of this solitary wavetrain. Our analytical solution is supported by direct numerical simulations. The presented analysis can be extended to other systems describing the propagation of undular bores (dispersive shock waves) in weakly non-uniform environments
Axon diversity of lamina I local-circuit neurons in the lumbar spinal cord
Spinal lamina I is a key area for relaying and integrating information from nociceptive primary afferents with various other sources of inputs. Although lamina I projection neurons have been intensively studied, much less attention has been given to local-circuit neurons (LCNs), which form the majority of the lamina I neuronal population. In this work the infrared light-emitting diode oblique illumination technique was used to visualize and label LCNs, allowing reconstruction and analysis of their dendritic and extensive axonal trees. We show that the majority of lamina I neurons with locally branching axons fall into the multipolar (with ventrally protruding dendrites) and flattened (dendrites limited to lamina I) somatodendritic categories. Analysis of their axons revealed that the initial myelinated part gives rise to several unmyelinated small-diameter branches that have a high number of densely packed, large varicosities and an extensive rostrocaudal (two or three segments), mediolateral, and dorsoventral (reaching laminae III–IV) distribution. The extent of the axon and the occasional presence of long, solitary branches suggest that LCNs may also form short and long propriospinal connections. We also found that the distribution of axon varicosities and terminal field locations show substantial heterogeneity and that a substantial portion of LCNs is inhibitory. Our observations indicate that LCNs of lamina I form intersegmental as well as interlaminar connections and may govern large numbers of neurons, providing anatomical substrate for rostrocaudal “processing units” in the dorsal horn
The Th1:Th2 Dichotomy of Pregnancy and Preterm Labour
Pregnancy is a unique immunological state in which a balance of immune tolerance and suppression is needed to protect the fetus without compromising the mother. It has long been established that a bias from the T helper 1 cytokine profile towards the T helper 2 profile contributes towards successful pregnancy maintenance. The majority of publications that report on aberrant Th1:Th2 balance focus on early pregnancy loss and preeclampsia. Over the last few decades, there has been an increased awareness of the role of infection and inflammation in preterm labour, and the search for new biomarkers to predict preterm labour continues. In this paper, we explore the evidence for an aberrant Th1:Th2 profile associated with preterm labour. We also consider the potential for its use in screening women at high risk of preterm labour and for prophylactic therapeutic measures for the prevention of preterm labour and associated neonatal adverse outcomes
Changes in the Th1 : Th2 Cytokine Bias in Pregnancy and the Effects of the Anti-Inflammatory Cyclopentenone Prostaglandin 15-Deoxy-Δ12,14-Prostaglandin J2
Pregnancy is a complex immunological state in which a bias towards T helper 2 (Th2) protects the fetus. Evidence suggests that proinflammatory cytokines increase the risk of poor neonatal outcome, independently of the direct effect of preterm labour. The anti-inflammatory prostaglandin 15-deoxy-Δ12,14-Prostaglandin J2 (15dPGJ2) inhibits nuclear factor Kappa B (NF-κB) in amniocytes and myocytes in vitro and is a ligand for the chemoattractant receptor-homologous molecule expressed on Th2 cells (CRTH2) receptor. Here we examine the Th1:Th2 cytokine bias in pregnancy and whether 15dPGJ2 could be used to inhibit the production of the proinflammatory cytokines through inhibition of NF-κB while simultaneously promoting Th2 interleukin 4 (IL-4) synthesis via CRTH2 in T helper cells. Peripheral blood mononuclear cells (PBMCs) from women at 28 weeks, term pre-labour, term labour as well as non-pregnant female controls were cultured with 15dPGJ2 or vehicle control and stimulated with phorbol myristyl acetate (PMA)/ionomycin. The percentage of CD4+ cells producing interferon gamma (IFN-γ) and tumor necrosis factor alpha (TNF-α) in response to PMA/ionomycin was significantly reduced in pregnancy. 15dPGJ2 reduced IFN-γ and TNF-α production in stimulated T helper cells, but did not alter IL-4 production in CRTH2+ve cells. 15dPGJ2 also reduced phospho-p65 in stimulated PBMCs. In summary, 15dPGJ2 suppresses the Th1 response of PBMCs during pregnancy and active labour whilst maintaining the Th2 response suggesting a therapeutic benefit in reducing neonatal morbidity in inflammation-induced PTL
Towards ontology-driven navigation of the lipid bibliosphere
10.1186/1471-2105-9-S1-S5BMC Bioinformatics9SUPPL. 1BBMI
The covid-19 learning crisis as a challenge and an opportunity for schools: An evidence review and conceptual synthesis of research-based tools for sustainable change
This paper advances our understanding of how schools can become change agents capable of transforming local practice to address the challenges arising from the Covid-19 pandemic. It presents a novel application of cultural-historical activity theory to reinterpret evidence on widespread learning loss and increasing educational inequities resulting from the pandemic, and to identify scalable transformative learning opportunities through reframing the crisis as a double stimulation. By reviewing evidence of the emerging educational landscape, we first develop a picture of the new ‘problem space’ upon which schools must act. We develop a problem space map to serve as the first stimulus to articulate local challenges. Integrating this problem space with research on professional change, we identify conceptual tools to capture learning gaps and implement pedagogic interventions at scale, in order to enhance schools’ agency in directly addressing the crisis. These tools can act as the second stimulus, enabling educators to address local challenges. We conclude by discussing the Covid-19 educational crisis as a unique stimulus for professional learning and outline the potential for durable shifts in educational thinking and practice beyond the pandemic. We argue that this unprecedented historic disruption can be harnessed as a transformative professional learning opportunity. In particular, we consider how research on professional change offers local, scalable interventions and tools that can support educators in preventing the new insights from ‘slipping away’ post-pandemic. Utilising the notions of boundaries and tool-mediated professional change, we examine the ways in which this disruption generates opportunities to envision alternative futures for equitable learning in school.Author 1:
The epiSTEMe project [grant number RES-179-25-0003, PI Prof. K. Ruthven]
The TEACh project [ES/M005445/1, PI Prof. P. Rose]
ESRC Impact Acceleration Grant, University of Cambridge [PI Dr. R. Hofmann]
Cambridge University Health Partners
Commonwealth Education Trust (PI. Prof. S. Hennessy)
Authors 2-8:
(2) Faculty of Education, University of Cambridge, PhD scholarship
(3) Economic and Social Research Council PhD scholarship [ES/P000738/1]
(4) Agencia Nacional de Investigación y Desarrollo (ANID), Cambridge Trust, PhD scholarship
(5) Economic and Social Research Council [ES/P000738/1] and MRC Epidemiology Unit PhD scholarship
(6) Yayasan Khazanah, Cambridge Trust, PhD scholarship
(7) Guy’s and St Thomas’ Charity, UK [TCF180902] PhD scholarship
(8) The LEGO Foundatio
Chaotic Microcavity Laser with Low threshold and Unidirectional Output
Here we report lasing action in lima\c{c}on-shaped GaAs microdisks with
quantum dots (QDs) embedded. Although the intracavity ray dynamics is
predominantly chaotic, high- modes are concentrated in the region as a result of wave localization. Strong optical confinement by total
internal reflection leads to very low lasing threshold. Our measurements show
that all the lasing modes have output in the same direction, regardless of
their wavelengths and intracavity mode structures. This universal emission
direction is determined by directed phase space flow of optical rays in the
open chaotic cavity. The divergence angle of output beam is less than 40
degree. The unidirectionality proves to be robust against small deviations of
the real cavity shape and size from the designed values.Comment: 12 pages, 4 figure
Variable-Speed PICO Hydel Energy Storage With Synchronverter Control to Emulate Virtual Inertia in Autonomous Microgrids
An approach to enhance the durability and mechanical properties of Class G cement using nano materials
Maintaining the integrity of the cement used to seal off the injection intervals of sequestrations sites is crucial to confine CO2 for thousands of years. There have been many studies to resolve the issue of cement degradation induced in the presence of CO2, but a very limited success has been reported to the application of the approaches proposed so far. Nano materials have gained the attention of many researchers in the past decade and might be able to resolve the issue of cement degradation given their outstanding performance and proven applications in the civil and polymer industries. In this paper, attempts are made to improve the physical and mechanical characteristics of class G cement using nano glass flakes (NGFs) and multiple-walled carbon nanotubes (MWCNTs). To do this, different cement-nanocomposites were prepared using two mixing techniques and their physical and mechanical changes were evaluated under different curing conditions. Samples with cylindrical shape of were prepared and cured under the temperature of 50°C and atmospheric pressure for 1 days. The results obtained indicated both nanoparticles are neutrally stable and may have a very slight effect on the cement rheology but may significantly increase the strength of the cement. It was concluded that the cement with 0.05 wt.% MWCNTs can provide the best results in terms of rheology, compositional changes and compressive strength
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