Precision testing the Standard Model

Internal consistency of the most sensitive electroweak measurements within the standard model framework is examined. Confirming an earlier observation on the separation of Z-pole asymmetry measurements into {\em hadronisation- free}and {\em hadronisation-sensitive}, the electroweak mixing angle derived using the former is in perfect agreement with the precision W mass. These two complimentary measurements of weak radiative corrections, when combined with the lower limit on Higgs mass, are incompatible with the measured top quark mass. To overcome this inconsistency, a scenario readily testable in Run-II at Tevatron is envisaged: an upward shift of the top quark mass by about 10 GeV ($\sim 2\sigma$). If, however, the improved top quark mass remains at its current value or the lower limit on Higgs mass moves up substantially, then abandoning the SM may become inevitable.Comment: 7 pages, 4 figure

Recycling and the Environment: a Comparative Review Between Mineral-based Plastics and Bioplastics

Since their conception in the 1950s, mineral-based plastics have completely revolutionised our society with production reaching record highs year upon year. This cheap, and durable material has seen usage across a plethora of diverse industries and products, replacing traditional materials such as metals and wood. However, our reliance on mineral-based plastics has led to their improper disposal across the global, affecting our environments and ecosystems. As a response, different methods have been developed to help dispose of the large amounts of plastic waste produced, such as incineration or dumping in landfill sites, but these methods are not without their drawbacks including release of toxic substances into the air and leachate into the soil and waters respectively. Consequently, much interest is generated and channelled in recent years to the introduction of several types of biopolymers. These include plastics based on cellulosic esters, starch derivatives, polyhydroxybutyrate and polylactic acid. These biopolymers have been viewed as a suitable replacement for mineral-based plastics, and their production a good strategy towards sustainable development as they are mainly composed of biocompounds such as starch, cellulose and sugars. This short review article provides an overview as to whether biopolymers can rival mineral-based plastics considering properties such as mechanical strength, Young’s modulus and crystallinity and could they be regarded as a suitable material to reduce our reliance on mineral-based plastics, whilst simultaneously reducing non-renewable energy consumption and carbon dioxide emissions

Asymmetry measurements at LEP/SLC revisited

We examine the fermion asymmetry measurements at LEP and SLC leading to effective weak mixing angle, sin2.theta.eff. We notice very interesting regularity in these measurements. All asymmetry measurements fall in two classes. Class A measurements where hadronisation effects are not relevant for the final result and class B measurements where hadronisation effects can not be avoided and can only be corrected with whatever understanding of these phenomena we have. In each of these classes there is excellent agreement between LEP and SLC results. However the two classes are distinctly apart by more than 3.sigma.. We suggest that for precision test of the standard model the class A measurements should be preferred

Thermal finite-element analysis of space shuttle main engine turbine blade

Finite-element, transient heat transfer analyses were performed for the first-stage blades of the space shuttle main engine (SSME) high-pressure fuel turbopump. The analyses were based on test engine data provided by Rocketdyne. Heat transfer coefficients were predicted by performing a boundary-layer analysis at steady-state conditions with the STAN5 boundary-layer code. Two different peak-temperature overshoots were evaluated for the startup transient. Cutoff transient conditions were also analyzed. A reduced gas temperature profile based on actual thermocouple data was also considered. Transient heat transfer analyses were conducted with the MARC finite-element computer code

The Deepest Supernova Search is Realized in the Hubble Ultra Deep Field Survey

The Hubble Ultra Deep Field Survey has not only provided the deepest optical and near infrared views of universe, but has enabled a search for the most distant supernovae to z~2.2. We have found four supernovae by searching spans of integrations of the Ultra Deep Field and the Ultra Deep Field Parallels taken with the Hubble Space Telescope paired with the Advanced Camera for Surveys and the Near Infrared Multi Object Spectrometer. Interestingly, none of these supernovae were at z>1.4, despite the substantially increased sensitivity per unit area to such objects over the Great Observatories Origins Deep Survey. We present the optical photometric data for the four supernovae. We also show that the low frequency of Type Ia supernovae observed at z>1.4 is statistically consistent with current estimates of the global star formation history combined with the non-trivial assembly time of SN Ia progenitors.Comment: 24 pages (6 figures), submitted to the Astronomical Journa

Thermal Residual Stress in Environmental Barrier Coated Silicon Nitride - Modeled

When exposed to combustion environments containing moisture both un-reinforced and fiber reinforced silicon based ceramic materials tend to undergo surface recession. To avoid surface recession environmental barrier coating systems are required. However, due to differences in the elastic and thermal properties of the substrate and the environmental barrier coating, thermal residual stresses can be generated in the coated substrate. Depending on their magnitude and nature thermal residual stresses can have significant influence on the strength and fracture behavior of coated substrates. To determine the maximum residual stresses developed during deposition of the coatings, a finite element model (FEM) was developed. Using this model, the thermal residual stresses were predicted in silicon nitride substrates coated with three environmental coating systems namely barium strontium aluminum silicate (BSAS), rare earth mono silicate (REMS) and earth mono di-silicate (REDS). A parametric study was also conducted to determine the influence of coating layer thickness and material parameters on thermal residual stress. Results indicate that z-direction stresses in all three systems are small and negligible, but maximum in-plane stresses can be significant depending on the composition of the constituent layer and the distance from the substrate. The BSAS and REDS systems show much lower thermal residual stresses than REMS system. Parametric analysis indicates that in each system, the thermal residual stresses can be decreased with decreasing the modulus and thickness of the coating

A hemophagocytic lymphohistiocytosis case with newly defined UNC13D (C.175G>C; p.Ala59Pro) mutation and a rare complication

Hemophagocytic lymphohistiocytosis (HLH) represents a severe hyperinflammatory condition with cardinal symptoms of prolonged fever, cytopenias, hepatosplenomegaly, and hemophagocytosis by activated, morphologically benign macrophages with impaired function of natural killer cells and cytotoxic T lymphocytes. A 2-month-old girl, who was admitted with fever, was diagnosed with HLH and her genetic examination revealed a newly defined mutation in the UNC13D (c.175G>C; p.Ala59Pro) gene. She was treated with dexamethasone, etoposide, and intrathecal methotrexate. During the second week of treatment, after three doses of etoposide, it was noticed that there was a necrotic plaque lesion on the soft palate. Pathologic examination of debrided material in PAS and Grocott staining revealed lots of septated hyphae, which was consistent with aspergillosis infection. Etoposide was stopped and amphotericin B treatment was given for six weeks. HLH 2004 protocol was completed to eight weeks with cyclosporine A orally. There was no patient with invasive aspergillosis infection as severe as causing palate and nasal septum perforation during HLH therapy. In immuncompromised patients, fungal infections may cause nasal septum perforation and treatment could be achieved by antifungal therapy and debridement of necrotic tissue. © 2015 Turkish Society of Hematology. All rights reserved