5,449 research outputs found
The prognostic role of VEGF in head and neck squamous cell carcinoma
Emerging from potentially malignant disorders that in most cases will never become cancerous, head and neck squamous cell carcinoma (HNSCC) is a cancer that is extremely difficult to diagnose early. This late stage diagnosis has allowed limited improvements in overall survival (OS) as patients are prone to local recurrence, secondary primary tumors, and distant metastasis. As a result, it has become vitally important to assess the prognostic value of biological marker screening to provide an avenue for early diagnosis and identification of local recurrence or residual secondary tumor sites. Many characteristic markers such as EGFR, p16, p53 and VEGF that are constitutively mutated in HNSCC have been identified. However, the dysregulation of VEGF marks a landmark mutation that accelerates the diseases progression and spread. An angiogenic protein normally expressed in response to hypoxic conditions, VEGF allows the creation of new vasculature to remove catabolites and bestows resistance to normal cellular apoptotic signals; pathways often employed by chemotherapeutics. Therefore, early identification of VEGF poses a unique opportunity to employ aggressive therapeutic regimens in combination with precision surgical resection to eliminate the cancer before neovascualture invasion has occurred and the tumor has expanded significantly. For this reason, this review will examine the current literature available on VEGFs role in HNSCC, its value as a prognostic marker
Bulk gauge and matter fields in nested warping: I. the formalism
The lack of evidence for a TeV-mass graviton has been construed as
constricting the Randall-Sundrum model. However, a doubly-warped generalization
naturally avoids such restrictions. We develop, here, the formalism for
extension of the Standard Model gauge bosons and fermions into such a
six-dimensional bulk. Apart from ameliorating the usual problems such as
flavour-changing neutral currents, this model admits two very distinct phases,
with their own unique phenomenologies.Comment: 44 pages, 5 figures, version to appear in JHEP. Corrected minor
typographical error
Real Options: Applications in Public Economics
This paper illustrates the use of real options principles to value prototypical resource and industryinvestment projects. It captures important competitive/strategic dimensions in a step-by-stepanalysis of investment decisions (options) under uncertainty. It compares and contrasts staticdiscounted cash flow analysis (DCF) with real options analysis using three case studies. The initialexample values a resource extraction process using static DCF and then compares the projectvaluation when future information is valued and acted upon. The second example considers a coaldevelopment and uses the binomial valuation approach to capture the option value associated withhaving the right but not the obligation to exit the development. It contrasts this valuation approachagainst static DCF and highlights that future royalty payments could be underestimated if based onthe standard DCF valuation. The third example analyses the impact of providing a subsidy forhybrid vehicle production to accelerate potential uncertain environmental benefits. Lastly, thesuitability of the standard financial and economic evaluation tools used by treasury agencies isconsidered when projects contain real options.financial economics; investment decisions; public economics; externalities; subsidies; project evaluation
Universal Extra Dimensions and the Graviton Portal to Dark Matter
The Universal Extra Dimension (UED) paradigm is particularly attractive as it
not only includes a natural candidate for the Dark Matter particle but also
addresses several issues related to particle physics. Non-observations at the
Large Hadron Collider, though, has brought the paradigm into severe tension.
However, a particular 5-dimensional UED model emerges from a six-dimensional
space-time with nested warping. The bulk protects both the Higgs mass
as well as the UED scale without invoking unnatural parameter values. The
graviton excitations in the sixth direction open up new (co-)annihilation
channels for the Dark Matter particle, thereby allowing for phenomenological
consistency, otherwise denied to the minimal UED scenario. The model leads to
unique signatures in both satellite-based experiments as well as the LHC.Comment: 16 pages, 4 figures, To be published in JCA
Hydrogen applications for Lambert - St. Louis International Airport
Today, major airports are facing challenges related to pollution, energy efficiency, and safety and security. Hydrogen and fuel cell technologies, regarded as one of the key energy solutions of the 21st century are more energy efficient and reliable than conventional systems and have the potential to diminish these challenges. These technologies can also play a significant role in reducing the noise, air, and water pollution and enhancing energy security. This paper presents the design of a set of hydrogen technologies and systems that are commercially available and are ready for practical, real-world use. The hydrogen applications selected for Lambert-St. Louis Airport include a hydrogen fueling station, back-up and auxiliary power systems, portable emergency power, light-duty vehicle applications, and a stand-alone system designed for public exposure to hydrogen technologies. Specifically, the selected back-up and auxiliary power systems will displace existing battery and diesel power systems with fuel cells. All hydrogen systems selected will comply with or exceed the existing safety codes and standards. The economic feasibility and environmental impacts of hydrogen applications at airport were studied. A marketing and educational plan was formulated to educate the airport staff and public and to alleviate any concerns regarding the introduction of hydrogen technologies at the airport. Consequently, increased safety and security, higher energy efficiency, reduction in pollution, and smaller impact during power interruptions achieved by using hydrogen technologies will benefit the airport --Abstract, page iii
Graviton modes in multiply warped geometry
The negative results in the search for Kaluza-Klein graviton modes at the
LHC, when confronted with the discovery of the Higgs, has been construed to
have severely limited the efficacy of the Randall-Sundrum model as an
explanation of the hierarchy problem. We show, though, that the presence of
multiple warping offers a natural resolution of this conundrum through
modifications in both the graviton spectrum and their couplings to the Standard
Model fields.Comment: 16 pages, 6 figure
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