Advanced technology for minimum weight pressure vessel system

Bosses were made of fiber/resin composite materials to evaluate their potential in lightweight pressure vessels. An approximate 25% weight savings over the standard aluminum boss was achieved without boss failures during burst tests. Polymer liners and metal liners are used in fiber composite pressure vessels for containment of gases. The internal support of these liners required during the filament winding process has previously been provided by dissolvable salt mandrels. An internal pressurization technique has been developed which allows overwinding the liner without other means of support and without collapse. Study was made of several additional concepts including styrene/Saran, styrene/flexible epoxy

High-performance fiber/epoxy composite pressure vessels

Activities described include: (1) determining the applicability of an ultrahigh-strength graphite fiber to composite pressure vessels; (2) defining the fatigue performance of thin-titanium-lined, high-strength graphite/epoxy pressure vessel; (3) selecting epoxy resin systems suitable for filament winding; (4) studying the fatigue life potential of Kevlar 49/epoxy pressure vessels; and (5) developing polymer liners for composite pressure vessels. Kevlar 49/epoxy and graphite fiber/epoxy pressure vessels, 10.2 cm in diameter, some with aluminum liners and some with alternation layers of rubber and polymer were fabricated. To determine liner performance, vessels were subjected to gas permeation tests, fatigue cycling, and burst tests, measuring composite performance, fatigue life, and leak rates. Both the metal and the rubber/polymer liner performed well. Proportionately larger pressure vessels (20.3 and 38 cm in diameter) were made and subjected to the same tests. In these larger vessels, line leakage problems with both liners developed the causes of the leaks were identified and some solutions to such liner problems are recommended

Struggling and juggling: a comparison of assessment loads in research and teaching-intensive universities

In spite of the rising tide of metrics in UK higher education, there has been scant attention paid to assessment loads, when evidence demonstrates that heavy demands lead to surface learning. Our study seeks to redress the situation by defining assessment loads and comparing them across research-and teaching intensive universities. We clarify the concept of ‘assessment load’ in response to findings about high volumes of summative assessment on modular degrees. We define assessment load across whole undergraduate degrees, according to four measures: the volume of summative assessment; volume of formative assessment; proportion of examinations to coursework; number of different varieties of assessment. All four factors contribute to the weight of an assessment load, and influence students’ approaches to learning. Our research compares programme assessment data from 73 programmes in 14 UK universities, across two institutional categories. Research-intensives have higher summative assessment loads and a greater proportion of examinations; teaching-intensives have higher varieties of assessment. Formative assessment does not differ significantly across both university groups. These findings pose particular challenges for students in different parts of the sector. Our study questions the wisdom that ‘more’ is always better, proposing that lighter assessment loads may make room for ‘slow’ and deep learning

Regional clinical registry data show increased incidence of cutaneous melanoma in Cape Town

Cutaneous melanoma is a skin tumour that continues to result in a high mortality rate, particularly in the case of thick tumours and those that are deeply invasive histologically. It occurs in all populations but is most common in fair-skinned individuals, especially those with skin types 1 and 2 that tan poorly or not at all. There is epidemiological evidence for the pathogenetic role of ultraviolet light, particularly intense childhood exposure, although the relationship is complex. Genetic factors also play a role, as exemplified by families with both atypical naevi and melanoma. The rising incidence of melanoma, noted initially in countries with high levels of UV light, appears to be levelling off or decreasing in some areas. The pattern of these trends is inconsistent, with even European countries showing great variation. An epidemiological study performed in Cape Town from 1990 to 1995 demonstrated an incidence of melanoma of 24.4 per 100 000 white people per annum. We conducted a methodologically identical study in the same geographical area after a 10-year interval, to identify whether there is a trend in the incidence of melanoma in this area

Long-term safety of glycopyrrolate: A randomized study in patients with moderate-to-severe COPD (GEM3)

AbstractBackgroundChronic obstructive pulmonary disease (COPD) is one of the leading causes of death in the United States. Long-acting muscarinic antagonists (LAMAs) are a class of medications used as maintenance therapy for COPD. The GEM3 (Glycopyrrolate Effect on syMptoms and lung function) study assessed the long-term safety and efficacy of a LAMA, glycopyrrolate (GLY) 15.6 μg twice daily (b.i.d.), compared with an approved long-acting β2-agonist (LABA), indacaterol (IND) 75 μg once daily (q.d.) in patients with stable, symptomatic COPD with moderate-to-severe airflow limitation.MethodsThis 52-week, multicenter, double-blind, parallel-group study randomized patients (1:1) of the United States to receive GLY 15.6 μg b.i.d. or IND 75 μg q.d. both delivered via the Neohaler® device. The primary objective was to assess the safety and tolerability in terms of adverse event (AE) reporting rates over 52 weeks. Safety was also determined by evaluating multiple secondary endpoints, including vital signs, electrocardiograms (ECGs), and time to first moderate or severe exacerbation. Efficacy-related secondary endpoints included pre-dose forced expiratory volume in one second (FEV1) and forced vital capacity (FVC).ResultsOf the 511 randomized patients (GLY, n = 254; IND, n = 257), 81.6% completed the study. The overall incidences of AEs (GLY, 77.3%; IND, 77.0%) and serious AEs (GLY, 13.1%; IND, 13.3%) were comparable between the groups. The incidence of major adverse cardiovascular events was low and comparable between the groups. No clinically relevant differences for vital signs or ECG parameters were observed between the treatment groups. The three sudden deaths reported within 30 days of the treatment (GLY, n = 2; IND, n = 1) were adjudicated as unrelated to the study medication. In terms of efficacy, GLY 15.6 μg b.i.d. showed improvements in pre-dose FEV1 and FVC from baseline, which was comparable to those with IND 75 μg q.d., with no statistically significant differences. No significant differences were observed between the treatment groups in the time to first moderate or severe COPD exacerbation.ConclusionGLY 15.6 μg b.i.d. showed a long-term safety profile comparable to that of IND 75 μg q.d. and provided rapid and sustained bronchodilation over 52 weeks in patients with COPD with moderate-to-severe airflow limitation.Clinical trial registration numberNCT01697696

Enhanced Direct CP Violation in B±→ρ0π±B^{\pm} \to \rho^{0} \pi^{\pm}

We study direct CP violation in the hadronic decay $B^{\pm} \to \rho^{0}\pi^{\pm}$, including the effect of $\rho - \omega$ mixing. We find that the CP violating asymmetry is strongly dependent on the CKM matrix elements, especially the Wolfenstein parameter $\eta$. For fixed $N_{c}$ (the effective parameter associated with factorization), the CP violating asymmetry, $a$, has a maximum of order $30$ when the invariant mass of the $\pi^{+}\pi^{-}$ pair is in the vicinity of the $\omega$ resonance. The sensitivity of the asymmetry, $a$, to $N_{c}$ is small. Moreover, if $N_{c}$ is constrained using the latest experimental branching ratios from the CLEO collaboration, we find that the sign of $\sin \delta$ is always positive. Thus, a measurement of direct CP violation in $B^{\pm} \to \rho^{0}\pi^{\pm}$ would remove the mod$(\pi)$ ambiguity in ${\rm arg}[ - \frac{V_{td}V_{tb}^{\star}}{V_{ud}V_{ub}^{\star}}]$.Comment: 37 pages, 7 figure

Glossary of Botanical Terms (version 1)

No ISBN for whole work. The new 5th ed. is published online in PDF chapters, each with own ISBN. Updated and revised chapters will receive a new, different ISBNs -- from Introduction.The illustrations are, as far as possible, based on species in this Flora. In many cases the drawing is of a form which is not the commonest in the species used, so that the species cited should not be expected always to display the character as illustrated.J. P. Jessop, H. R. Toelken & J. Kellerman

Final-State Phases in B→B \to Baryon-Antibaryon Decays

The recent observation of the decay \ob \to \Lambda_c^+ \bar p suggests that related decays may soon be visible at $e^+ e^-$ colliders. It is shown how these decays can shed light on strong final-state phases and amplitudes involving the spectator quark, both of which are normally expected to be small in B decays.Comment: 14 pages, LaTeX, 2 figures, submitted to Phys. Rev. D, references and discussion of helicity amplitudes adde

Exclusive Hadronic D Decays to eta' and eta

Hadronic decay modes $D^0\to(\bar K^0, \bar K^{*0})\eta,\eta'$ and $(D^+,D_s^+)\to(\pi^+,\rho^+)\eta,\eta'$ are studied in the generalized factorization approach. Form factors for $(D,D_s^+)\to(\eta,\eta')$ transitions are carefully evaluated by taking into account the wave function normalization of the eta and eta'. The predicted branching ratios are generally in agreement with experiment except for $D^0\to\bar K^0\eta', D^+\to\pi^+\eta$ and $D_s^+\to\rho^+\eta'$; the calculated decay rates for the first two decay modes are too small by an order of magnitude. We show that the weak decays $D^0\to K^-\pi^+$ and $D^+\to K^+\bar K^0$ followed by resonance-induced final-state interactions (FSI), which are amenable technically, are able to enhance the branching ratios of $D^0\to\bar K^0\eta'$ and $D^+\to\pi^+\eta$ dramatically without affecting the agreement between theory and experiment for $D^0\to\bar K^0\eta$ and $D^+\to\pi^+\eta'$. We argue that it is difficult to understand the observed large decay rates of $D_s^+\to \rho^+\eta'$ and $\rho^+\eta$ simultaneously; FSI, W-annihilation and the production of excess eta' from gluons are not helpful in this regard. The large discrepancy between the factorization hypothesis and experiment for the ratio of $D_s^+\to\rho^+ \eta'$ and $D_s^+\to\eta' e^+\nu$ remains as an enigma.Comment: 15 pages, 1 figure, to appear in Phys. Rev. D. Form factors for D to eta and eta' transitions are slightly change

The Big Society and the Conjunction of Crises: Justifying Welfare Reform and Undermining Social Housing

The idea of the “Big Society” can be seen as culmination of a long-standing debate about the regulation of welfare. Situating the concept within governance theory, the article considers how the UK coalition government has justified a radical restructuring of welfare provision, and considers its implications for housing provision. Although drawing on earlier modernization processes, the article contends that the genesis for welfare reform was based on an analysis that the government was forced to respond to a unique conjunction of crises: in morality, the state, ideology and economics. The government has therefore embarked upon a programme, which has served to undermine the legitimacy of the social housing sector (most notably in England), with detrimental consequences for residents and raising significant dilemmas for those working in the housing sector