637 research outputs found
Advanced beaded and tubular structural panels
A program to develop lightweight beaded and tubular structural panels is described. Applications include external surfaces, where aerodynamically acceptable, and primary structure protected by heat shields. The design configurations were optimized and selected with a computer code which iterates geometric parameters to satisfy strength, stability, and weight constraints. Methods of fabricating these configurations are discussed. Nondestructive testing produced extensive combined compression, shear, and bending test data on local buckling specimens and large panels. The optimized design concepts offer 25 to 30% weight savings compared to conventional stiffened sheet construction
Potential For Power: A Symposium On The Prospects For Power From Currently Unconventional Energy Sources
The wave energy arriving on the west coast of the United Kingdom represents a very substantial energy resource, amounting on average to more than twice the present installed capacity of the CEGB. Recent, comprehensive, studies by the CEGB (1) (2) and the National Engineering Laboratory (3) suggest that although there is no obvious technical reason for being unable ultimately to harness much of this energy, and many methods have been proposed, there are still considerable uncertainties over the choice of wave power system and its economics. Wave power does show sufficient promise however to have been made the subject of serious studies supported by the CEGB and the Department of Energy (4). In this Paper the potential of wave power and some of the more promising methods of harnessing it are discussed, together with an appreciation of some of the many technical and engineering problems which still need to be examined, and a discussion of the impact of wave power on the environment. By considering the results of recent research and their impact on wave power economics it is argued that wave power could be exploited to conserve fossil fuels but is unlikely to be competitive with nuclear power
UK Large-scale Wind Power Programme from 1970 to 1990: the Carmarthen Bay experiments and the Musgrove Vertical-Axis Turbines
This article describes the development of the Musgrove Vertical Axis Wind Turbine (VAWT)
concept, the UK âCarmarthen Bayâ wind turbine test programme, and UK governmentâs wind
power programme to 1990. One of the most significant developments in the story of British
wind power occurred during the 1970s, 1980s, and 1990s, with the development of the
Musgrove vertical axis wind turbine and its inclusion within the UK Governmentâs wind
turbine test programme. Evolving from a supervisorâs idea for an undergraduate project at
Reading University, the Musgrove VAWT was once seen as an able competitor to the
horizontal axis wind systems that were also being encouraged at the time by both the UK
government and the Central Electricity Generating Board, the then nationalised electricity
utility for England and Wales. During the 1980s and 1990s the most developed Musgrove
VAWT system, along with three other commercial turbine designs was tested at
Carmarthen Bay, South Wales as part of a national wind power test programme. From these
developmental tests, operational data was collected and lessons learnt, which were
incorporated into subsequent wind power operations.http://dx.doi.org/10.1260/03095240677860621
EUV spectra of highly-charged ions W-W relevant to ITER diagnostics
We report the first measurements and detailed analysis of extreme ultraviolet
(EUV) spectra (4 nm to 20 nm) of highly-charged tungsten ions W to
W obtained with an electron beam ion trap (EBIT). Collisional-radiative
modelling is used to identify strong electric-dipole and magnetic-dipole
transitions in all ionization stages. These lines can be used for impurity
transport studies and temperature diagnostics in fusion reactors, such as ITER.
Identifications of prominent lines from several W ions were confirmed by
measurement of isoelectronic EUV spectra of Hf, Ta, and Au. We also discuss the
importance of charge exchange recombination for correct description of
ionization balance in the EBIT plasma.Comment: 11 pages, 4 figure
State-resolved valence shell photoionization of Be-like ions: experiment and theory
High-resolution photoionization experiments were carried out using beams of
Be-like C, N, and O ions with roughly equal populations of
the S ground-state and the P manifold of metastable components. The
energy scales of the experiments are calibrated with uncertainties of 1 to 10
meV depending on photon energy. Resolving powers beyond 20,000 were reached
allowing for the separation of contributions from the individual metastable
P, P, and P states. The measured data compare
favourably with semi-relativistic Breit-Pauli R-matrixComment: 23 figures and 3 table
Clinical and molecular characterization of HER2 amplified-pancreatic cancer
<p>Background:
Pancreatic cancer is one of the most lethal and molecularly diverse malignancies. Repurposing of therapeutics that target specific molecular mechanisms in different disease types offers potential for rapid improvements in outcome. Although HER2 amplification occurs in pancreatic cancer, it is inadequately characterized to exploit the potential of anti-HER2 therapies.</p>
<p>Methods:
HER2 amplification was detected and further analyzed using multiple genomic sequencing approaches. Standardized reference laboratory assays defined HER2 amplification in a large cohort of patients (n = 469) with pancreatic ductal adenocarcinoma (PDAC).</p>
<p>Results:
An amplified inversion event (1 MB) was identified at the HER2 locus in a patient with PDAC. Using standardized laboratory assays, we established diagnostic criteria for HER2 amplification in PDAC, and observed a prevalence of 2%. Clinically, HER2- amplified PDAC was characterized by a lack of liver metastases, and a preponderance of lung and brain metastases. Excluding breast and gastric cancer, the incidence of HER2-amplified cancers in the USA is >22,000 per annum.</p>
<p>Conclusions:
HER2 amplification occurs in 2% of PDAC, and has distinct features with implications for clinical practice. The molecular heterogeneity of PDAC implies that even an incidence of 2% represents an attractive target for anti-HER2 therapies, as options for PDAC are limited. Recruiting patients based on HER2 amplification, rather than organ of origin, could make trials of anti-HER2 therapies feasible in less common cancer types.</p>
A layering model for superconductivity in the borocarbides
We propose a superlattice model to describe superconductivity in layered
materials, such as the borocarbide families with the chemical formul\ae\
BC and BC, with being (essentially) a rare earth, and a
transition metal. We assume a single band in which electrons feel a local
attractive interaction (negative Hubbard-) on sites representing the B
layers, while U=0 on sites representing the C layers; the multi-band
structure is taken into account minimally through a band offset . The
one-dimensional model is studied numerically through the calculation of the
charge gap, the Drude weight, and of the pairing correlation function. A
comparison with the available information on the nature of the electronic
ground state (metallic or superconducting) indicates that the model provides a
systematic parametrization of the whole borocarbide family.Comment: 4 figure
Suicide and death by other causes among patients with a severe mental illness : cohort study comparing risks among patients discharged from inpatient care v. those treated in the community
Aims
People diagnosed with a severe mental illness (SMI) are at elevated risk of dying prematurely compared to the general population. We aimed to understand the additional risk among people with SMI after discharge from inpatient psychiatric care, when many patients experience an acute phase of their illness.
Methods
In the Clinical Practice Research Datalink (CPRD) GOLD and Aurum datasets, adults aged 18 years and older who were discharged from psychiatric inpatient care in England between 2001 and 2018 with primary diagnoses of SMI (schizophrenia, bipolar disorder, other psychoses) were matched by age and gender with up to five individuals with SMI and without recent hospital stays. Using survival analysis approaches, cumulative incidence and adjusted hazard ratios were estimated for all-cause mortality, external and natural causes of death, and suicide. All analyses were stratified by younger, middle and older ages and also by gender.
Results
In the year after their discharge, the risk of dying by all causes examined was higher than among individuals with SMI who had not received inpatient psychiatric care recently. Suicide risk was 11.6 times (95% CI 6.4â20.9) higher in the first 3 months and remained greater at 2â5 years after discharge (HR 2.3, 1.7â3.2). This risk elevation remained after adjustment for self-harm in the 6 months prior to the discharge date. The relative risk of dying by natural causes was raised in the first 3 months (HR 1.6, 1.3â1.9), with no evidence of elevation during the second year following discharge.
Conclusions
There is an additional risk of death by suicide and natural causes for people with SMI who have been recently discharged from inpatient care over and above the general risk among people with the same diagnosis who have not recently been treated as an inpatient. This mortality gap shows the importance of continued focus, following discharge, on individuals who require inpatient care
Performance-based financing as a health system reform : mapping the key dimensions for monitoring and evaluation
Peer reviewedPublisher PD
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