113 research outputs found
Technical committee on control education
Presents information of the CS society Presents information of the CS society Technical Committee on Control Education
Stochastic evolution equations driven by Liouville fractional Brownian motion
Let H be a Hilbert space and E a Banach space. We set up a theory of
stochastic integration of L(H,E)-valued functions with respect to H-cylindrical
Liouville fractional Brownian motions (fBm) with arbitrary Hurst parameter in
the interval (0,1). For Hurst parameters in (0,1/2) we show that a function
F:(0,T)\to L(H,E) is stochastically integrable with respect to an H-cylindrical
Liouville fBm if and only if it is stochastically integrable with respect to an
H-cylindrical fBm with the same Hurst parameter. As an application we show that
second-order parabolic SPDEs on bounded domains in \mathbb{R}^d, driven by
space-time noise which is white in space and Liouville fractional in time with
Hurst parameter in (d/4,1) admit mild solution which are H\"older continuous
both and space.Comment: To appear in Czech. Math.
Metformin:historical overview
Metformin (dimethylbiguanide) has become the preferred first-line oral blood glucose-lowering agent to manage type 2 diabetes. Its history is linked to Galega officinalis (also known as goat's rue), a traditional herbal medicine in Europe, found to be rich in guanidine, which, in 1918, was shown to lower blood glucose. Guanidine derivatives, including metformin, were synthesised and some (not metformin) were used to treat diabetes in the 1920s and 1930s but were discontinued due to toxicity and the increased availability of insulin. Metformin was rediscovered in the search for antimalarial agents in the 1940s and, during clinical tests, proved useful to treat influenza when it sometimes lowered blood glucose. This property was pursued by the French physician Jean Sterne, who first reported the use of metformin to treat diabetes in 1957. However, metformin received limited attention as it was less potent than other glucose-lowering biguanides (phenformin and buformin), which were generally discontinued in the late 1970s due to high risk of lactic acidosis. Metformin's future was precarious, its reputation tarnished by association with other biguanides despite evident differences. The ability of metformin to counter insulin resistance and address adult-onset hyperglycaemia without weight gain or increased risk of hypoglycaemia gradually gathered credence in Europe, and after intensive scrutiny metformin was introduced into the USA in 1995. Long-term cardiovascular benefits of metformin were identified by the UK Prospective Diabetes Study (UKPDS) in 1998, providing a new rationale to adopt metformin as initial therapy to manage hyperglycaemia in type 2 diabetes. Sixty years after its introduction in diabetes treatment, metformin has become the most prescribed glucose-lowering medicine worldwide with the potential for further therapeutic applications
Recommended from our members
Fundamental Science Investigations to Develop a 6-MV Laser Triggered Gas Switch for ZR: First Annual Report.
In October 2005, an intensive three-year Laser Triggered Gas Switch (LTGS) development program was initiated to investigate and solve observed performance and reliability issues with the LTGS for ZR. The approach taken has been one of mission-focused research: to revisit and reassess the design, to establish a fundamental understanding of LTGS operation and failure modes, and to test evolving operational hypotheses. This effort is aimed toward deploying an initial switch for ZR in 2007, on supporting rolling upgrades to ZR as the technology can be developed, and to prepare with scientific understanding for the even higher voltage switches anticipated needed for future high-yield accelerators. The ZR LTGS was identified as a potential area of concern quite early, but since initial assessments performed on a simplified Switch Test Bed (STB) at 5 MV showed 300-shot lifetimes on multiple switch builds, this component was judged acceptable. When the Z{sub 20} engineering module was brought online in October 2003 frequent flashovers of the plastic switch envelope were observed at the increased stresses required to compensate for the programmatically increased ZR load inductance. As of October 2006, there have been 1423 Z{sub 20} shots assessing a variety of LTGS designs. Numerous incremental and fundamental switch design modifications have been investigated. As we continue to investigate the LTGS, the basic science of plastic surface tracking, laser triggering, cascade breakdown, and optics degradation remain high-priority mission-focused research topics. Significant progress has been made and, while the switch does not yet achieve design requirements, we are on the path to develop successively better switches for rolling upgrade improvements to ZR. This report summarizes the work performed in FY 2006 by the large team. A high-level summary is followed by detailed individual topical reports
Influence of dried method of the mechanical and acoustic properties of dried carrot
Celem pracy było badanie wpływu metody suszenia na właściwości mechaniczne i akustyczne uzyskanych produktów oraz analiza korelacji pomiędzy wyznaczonymi wyróżnikami tekstury. Przeprowadzone badania wykazały, że metoda suszenia wpływa na właściwości mechaniczne i akustyczne suszy marchwiowych. Praca i siła ściskania były największe dla suszu fluidalnego i mikrofalowego. Susze różniły się zarówno liczbą zdarzeń emisji akustycznej jak i zakresem emitowanych częstotliwości. Współczynnik nachylenia charakterystyki widmowej był najwyższy dla suszu sublimacyjnego i różnił się istotnie od wartości uzyskanych dla suszu fluidalnego, mikrofalowego i konwekcyjnego. Nie stwierdzono istotnych korelacji pomiędzy wyróżnikami tekstury akustycznymi i mechanicznymi, natomiast wykazano, że parametry akustyczne zależą od porowatości materiału.The aim of this work was to investigate the influence of drying method on mechanical and acoustic properties of carrots. The correlations between the acoustic emission descriptors and mechanical features of texture of dried product were analyzed. Carrot of the Joba variety was cut into slices and then dried by convective method as well as by freeze-drying, fluidal and microwave. Samples of dried material were subjected to compression test. The test was performed with the application of the Zwick loading machine equipped with the system for registration of AE. Results showed that acoustic and mechanical properties were dependent on the drying method. The sound generated by the dried carrot differed in frequency according to the drying method. There was no correlation between mechanical and acoustic properties of the dry material. However, acoustic descriptors were correlated with porosity of dried carrot
Monitoring technical conditions of engineering structures using the terrestrial laser scanning technology
The laser scanning technology offers quite new possibilities in the field of the existing monitoring of engineering structures. The basic advantage of the laser scanning technology is huge amount of measuring observations and practically complete geometric and spectral information about the measured structures, which may be required within the short time. In the context of detection of threatens related to deformations and displacements of building structures, the surface - quasi-continuous distribution of measuring points is one of the most important factors. which ensure the possibility to perform correct evaluation of safety conditions of investigated structures. The proposed technological solution offers a series of new possibilities and the resulting methodology of determination of deformations and displacements of various structures, will considerably increase the scope of possible works and analyses. This will also create the new segment of data, which will result in delivery of additional information concerning conditions of the structure to experts from various fields, such as, among others, civil engineering, construction or geotechnique, who monitor the given structure
- …