Quantum cascade laser light propagation through hollow silica waveguides

In this paper, the transmission characteristics of hollow silica waveguides with bore diameters of 300 and 1000 μm are investigated using a 7.8-μm quantum cascade laser system. We show that the bore diameter, coiling and launch conditions have an impact on the number of supported modes in the waveguide. Experimental verification of theoretical predictions is achieved using a thermal imaging camera to monitor output intensity distributions from waveguides under a range of conditions. The thermal imaging camera allowed for more detailed images than could be obtained with a conventionally used beam profiler. The results show that quasi-single-mode transmission is achievable under certain conditions although guided single-mode transmission in coiled waveguides requires a smaller bore diameter-to-wavelength ratio than is currently available. Assessment of mode population is made by investigating the spatial frequency content of images recorded at the waveguide output using Fourier transform techniques

Maximum Normalized Rate as a Flying Qualities Parameter

Discrete attitude commands have become a standard task for flying qualities evaluation and control system testing. Much pilot opinion data is now available for ground-based and in-flight simulations, but adequate performance measures and prediction methods have not been established. The Step Target Tracking Prediction method, introduced in 1978, correlated time-on-target and rms tracking data with NT-33 in-flight longitudinal simulations, but did not employ parameters easily measured in manned flight and simulation. Recent application of the Step Target Tracking Prediction method to lateral flying qualities analysis has led to a new measure of performance. This quantity, called Maximum Normalized Rate (MNR), reflects the greatest attitude rate a pilot can employ during a discrete maneuver without excessive overshoot and oscillation. MNR correlates NT-33 lateral pilot opinion ratings well, and is easily measured during flight test or simulation. Futhermore, the Step Target MNR method can be used to analyze large amplitude problems concerning rate limiting and nonlinear aerodynamics

British research in accounting and finance (2001–2007): the 2008 research assessment exercise

No abstract available

Polymorphisms of the glucose transporter (GLUT1) gene are associated with diabetic nephropathy

Polymorphisms of the glucose transporter (GLUT1) gene are associated with diabetic nephropathy.BackgroundDiabetic nephropathy (DN) is a major cause of morbidity and mortality in patients with type 1 diabetes mellitus. Recent studies suggest that genetic factors, including polymorphisms in the flanking region of the aldose reductase gene (5′ALR2), play an important role in the pathogenesis of nephropathy. Glucose transporter (GLUT1) activity has been implicated in renal hypertrophy and extracellular matrix formation in mesangial cells. The aim was to investigate the frequency of a polymorphism within the GLUT1 gene in 186 Caucasoid patients with type 1 diabetes and 104 normal controls.MethodsAmplimers flanking the Xba-I polymorphic site in the second intron were employed to amplify DNA from subjects. The amplified DNA was restricted with endonuclease Xba-I, separated by gel electrophoresis, and visualized. In the absence of an Xba-I site, a fragment of 1.1 kilobase was seen, whereas fragments of 0.9 and 0.2 were generated if the Xba-I site was present.ResultsThere was a highly significant increase in the frequency of the 1.1 allele in those patients with nephropathy (N = 70) compared with those with no proteinuria or retinopathy after 20 years of diabetes (uncomplicated N = 44, 61.4 vs. 40.9%, respectively, P < 0.001). The 1.1/1.1 genotype was also significantly increased in the nephropathy group compared with the uncomplicated group of patients (37.1 vs. 13.6%, respectively, P < 0.01). The frequency of the 1.1/1.1 genotype was similar in 30 patients with retinopathy but not nephropathy when compared with the uncomplicated group of patients (13.6 vs. 16.7%). Furthermore, only 8 out of 49 patients with DN had the Z+2 5′ALR2 DN “protective” allele and the 0.9 GLUT1 allele in contrast to 21 out of 39 uncomplicated patients (P < 0.0002).ConclusionThese results suggest that the GLUT1 gene together with the aldose reductase gene are associated with susceptibility to DN in patients with type 1 diabetes

Perspective: Current advances in solid-state NMR spectroscopy

In contrast to the rapid and revolutionary impact of solution-state Nuclear Magnetic Resonance (NMR) on modern chemistry, the field of solid-state NMR has matured more slowly. This reflects the major technical challenges of much reduced spectral resolution and sensitivity in solid-state as compared to solution-state spectra, as well as the relative complexity of the solid state. In this perspective, we outline the technique developments that have pushed resolution to intrinsic limits and the approaches, including ongoing major developments in the field of Dynamic Nuclear Polarisation, that have enhanced spectral sensitivity. The information on local structure and dynamics that can be obtained using these gains in sensitivity and resolution is illustrated with a diverse range of examples from large biomolecules to energy materials and pharmaceuticals and from both ordered and highly disordered materials. We discuss how parallel developments in quantum chemical calculation, particularly density functional theory, have enabled experimental data to be translated directly into information on local structure and dynamics, giving rise to the developing field of “NMR crystallography

Blending of nanoscale and microscale in uniform large-area sculptured thin-film architectures

The combination of large thickness ($>3$ $\mu$m), large--area uniformity (75 mm diameter), high growth rate (up to 0.4 $\mu$m/min) in assemblies of complex--shaped nanowires on lithographically defined patterns has been achieved for the first time. The nanoscale and the microscale have thus been blended together in sculptured thin films with transverse architectures. SiO$_x$ ($x\approx 2$) nanowires were grown by electron--beam evaporation onto silicon substrates both with and without photoresist lines (1--D arrays) and checkerboard (2--D arrays) patterns. Atomic self--shadowing due to oblique--angle deposition enables the nanowires to grow continuously, to change direction abruptly, and to maintain constant cross--sectional diameter. The selective growth of nanowire assemblies on the top surfaces of both 1--D and 2--D arrays can be understood and predicted using simple geometrical shadowing equations.Comment: 17 pages, 9 figure

Attitudes toward law tech adoption: Findings from a survey of solicitors in England and Wales

The adoption of digital technologies and related advances in artificial intelligence in the delivery of legal services is an issue that has rightly been a major focus of attention over the past decade, given the potential of these developments to fundamentally transform how the sector operates in respect of all aspects of its work. However, the rate and character of adoption of any new technology is fraught with uncertainty. The displacement of traditional ways of working and the accompanying shift of mind-set needed to fully embrace the potential opportunities that a new technology may offer presents significant behavioural challenges. Hence, the adoption of legal technologies poses some highly important unanswered questions regarding the attitudes and behaviour of legal services professionals toward them. Addressing this shortfall, this report summarises the findings of a representative, cross-sectional survey of the attitudes and beliefs of 656 solicitors in England and Wales concerning the adoption of lawtech. The study, which was conducted online during February and March 2023, examined participants’ perceptions of the nature and extent of lawtech adoption, their attitudes, and beliefs towards lawtech, and the extent of their current and intended future usage of lawtech

Solicitors’ attitudes toward lawtech adoption: Summary of findings and implications for the legal sector

The adoption of digital technologies and related advances in artificial intelligence in the delivery of legal services is an issue that has rightly been a major focus of attention over the past decade, given the potential of these developments to fundamentally transform how the sector operates in respect of all aspects of its work. However, the rate and character of adoption of any new technology is fraught with uncertainty. The displacement of traditional ways of working and the accompanying shift of mind-set needed to fully embrace the potential opportunities that a new technology can offer presents significant behavioural challenges. Hence, the adoption of legal technologies poses some highly important unanswered questions regarding the attitudes and behaviour of legal services professionals toward them. Addressing this shortfall, this report summarises the findings of a representative, crosssectional survey of the attitudes and beliefs of 656 solicitors in England and Wales concerning the adoption of lawtech. The study, which was conducted online during February and March 2023, examined participants’ perceptions of the nature and extent of lawtech adoption, their attitudes and beliefs towards lawtech, and the extent of their current and intended future usage of lawtech. While the data were gathered in collaboration with The Law Society, the study was conceived and otherwise run independently by the authors of this report, a team of academic researchers based at the University and Manchester and University College London