Biodurability of Poly Implant Prothèse (PIP) breast implants: A prospective analysis of 1028 prostheses in 514 patients

Poly Implant Prothèse (PIP) was a company that manufactured substandard breast implants using cheaper non-medical grade silicon. Around 40,000 women in the UK are thought to have PIP implants inserted(1). The advice for Women in Wales is: seek clinical advice prior to requesting routine removal. If there is clinical need, the National Health Service (NHS) in Wales funds removal and replacement of PIP breast implants inserted privately. This is in contrast to NHS in England where only PIP implants placed on the NHS are replaced. The Department of Health estimates the rate of implant rupture or significant silicone bleed for PIP implants could rising to 15-30% after 10 years; whilst other brands demonstrate rupture rates of 10-14% after 10 years. Therefore, making this an important issue to address in terms of outcomes, implant longevity and health economics. We present the largest heterogenous (private and public health services) experience case series of PIP breast implants to date

On a maximal subgroup of the Thompson simple group

The present paper deals with a maximal subgroup of the Thompson group, namely the group $2^{1+8}_{+}{^{cdot}}A_{9}:= overline{G}.$ We compute its conjugacy classes using the coset analysis method, its inertia factor groups and Fischer matrices, which are required for the computations of the character table of $overline{G}$ by means of Clifford-Fischer Theory

F3rn.org DeFi

Leadership is searching for strategies to assist geo-based communities, cities, large and small towns, and neighborhoods in achieving independent and more decentralized, sustainable environmental practices. By employing a paradigm that encourages peer-to-peer fund raising and rewards participants by actively encouraging more civic engagement, the F3rn platform responds to this demand and helps to build a stronger local circular economy. The F3rn Defi Platform has made it possible to create a global ecosystem for recycling plastic waste. This ecosystem uses Algorand blockchain technology to provide unbanked people with access to financial services, job opportunities for the extremely poor through financial incentives, a sovereign digital ID, and transparency for tracking every link in the value chain of plastic recycling

Real-time localization using received signal strength

Locating and tracking assets in an indoor environment is a fundamental requirement for several applications which include for instance network enabled manufacturing. However, translating time of flight-based GPS technique for indoor solutions has proven very costly and inaccurate primarily due to the need for high resolution clocks and the non-availability of reliable line of sight condition between the transmitter and receiver. In this dissertation, localization and tracking of wireless devices using radio signal strength (RSS) measurements in an indoor environment is undertaken. This dissertation is presented in the form of five papers. The first two papers deal with localization and placement of receivers using a range-based method where the Friis transmission equation is used to relate the variation of the power with radial distance separation between the transmitter and receiver. The third paper introduces the cross correlation based localization methodology. Additionally, this paper also presents localization of passive RFID tags operating at 13.56MHz frequency or less by measuring the cross-correlation in multipath noise from the backscattered signals. The fourth paper extends the cross-correlation based localization algorithm to wireless devices operating at 2.4GHz by exploiting shadow fading cross-correlation. The final paper explores the placement of receivers in the target environment to ensure certain level of localization accuracy under cross-correlation based method. The effectiveness of our localization methodology is demonstrated experimentally by using IEEE 802.15.4 radios operating in fading noise rich environment such as an indoor mall and in a laboratory facility of Missouri University of Science and Technology. Analytical performance guarantees are also included for these methods in the dissertation --Abstract, page iv

Localization of Objects using Cross-correlation of Shadow Fading Noise and Copulas

While fading, in general, is detrimental to accurately localizing a target, fading correlation between adjacent receivers may be exploited to improve localization accuracy. Therefore, this paper presents a novel wireless localization scheme that employs a combination of cross-correlation between shadow fading noise and copula technique to recursively estimate the location of a transmitter. a stochastic filter that models multipath fading as an Ornstein-Uhlenbeck process followed by a Generalized Auto Regressive Conditional Heteroskedasticity (GARCH) filtering is proposed to extract shadow fading residuals from measured RSSI values. Subsequently, Student-t Copula function is used to create the log likelihood function, which acts as the cost function for localization, by combining spatial shadow fading correlation arising among adjacent receivers due to pedestrian traffic in the area. Maximum Likelihood Estimate (MLE) is used for position estimation as it inherits the statistical consistency and asymptotic normality. the performance of our proposed localization method is validated over simulations and hardware experiments. © 2011 IEEE

Localization of Objects using Stochastic Tunneling

This paper presents a novel wireless localization scheme in the three-dimensional domain that employs stochastic optimization with tunneling transformation to recursively estimate the location of wireless tags in a network from pair wise signal strength measurements. Spatially co-located wireless tags, receiving signals from a common transmitter, exhibit correlation in their Received Signal Strength Indicator (RSSI) values. Hence in a network of wireless tags, with pair wise correlation coefficients available, posterior distribution of the unknown tag separation is used to relatively localize them using maximum a posteriori (MAP) Estimator. However, due to the non-convex/non-tractable nature of this posterior distribution, deterministic optimization methods will end in one of the many local maxima unless the initial guess is close to the region of attraction of the global maximum. in this paper, a novel stochastic localization method called LOCalization using Stochastic Tunneling (LOCUST) is proposed which utilizes constrained simulated annealing with tunneling transformation to solve this non-tractable posterior distribution. the tunneling transformation allows the optimization search operation to circumvent or tunnel through ill-shaped regions in the posterior distribution resulting in faster convergence to global maximum. Finally, simulation results of our localization method are presented. © 2011 IEEE

A New Receiver Placement Scheme using Delaunay Refinement-Based Triangulation

In this paper, a sub-optimal solution to the receiver placement and number of receiver determination problem is introduced. to achieve this overall goal, first, localization error for a received signal strength indicator (RSSI)-Based N-receiver system localizing a transmitter is estimated. Subsequently, this estimator error along with the 2D-tessellation techniques such as Delaunay refinement are used to position candidate receivers not only to minimize their number needed to meet the location error threshold but also to reduce the dilution of localization accuracy due to the layout of receivers. Rigorous mathematical analysis indicates that the receiver count generated by our Delaunay Refinement-Based suboptimal solution using triangular tiles is indeed bounded from the optimal count by a constant which in turn depends upon the workspace layout. Finally, the sub-optimal scheme is demonstrated by using experimental data. ©2010 IEEE

Would Africa’s largest hydropower dam have profound environmental impacts?

In the face of rapid growth in the global demands for water, energy, and food, building large dams is expected to continue. Due to its potential opportunities and risks for the people of the Eastern Nile Basin, the Grand Ethiopian Renaissance Dam (GERD) on the Nile River has commanded regional and international attention. Once completed, it will rank the largest hydropower dam in Africa and among the largest worldwide. Discourse among scientists and negotiators from Ethiopia, Sudan, and Egypt on the design, initial filling, and long-term operation of the GERD is ongoing since the construction started in 2011, but no agreement has yet been reached. The discourse has hitherto focused on the impacts on hydropower production, water availability, and irrigated agriculture, with little attention to the dam’s potential environmental impacts. Here, we communicate our viewpoint on this gap, drawing on knowledge from other dams around the world and some GERD characteristics. The hydrological alterations associated with the GERD could adversely impact fish, aquatic plants, and biodiversity in the downstream due to possible changes in water temperature, salinity, and oxygen content. The GERD’s expected flooded area, location at low latitude in the tropics, and the deep turbine intakes could intensify greenhouse gas emissions, whereas the dam’s high reservoir depth would abate the emissions. The dam’s electricity could also reduce regional greenhouse gas emissions if combined with cleaner intermittent solar and wind energy sources. With a maximum reservoir area of 1904 km2, surface evaporation and consequently local extreme precipitation and humidity could increase. The aforementioned impacts could have transboundary ecological, agricultural, and health implications and, therefore, should be taken into consideration alongside the benefits of the dam

Character tables of the general linear group and some of its subgroups

Thesis (M.Sc. (School of Mathematical Sciences)) - University of KwaZulu-Natal, Pietermaritzburg, 2008.The aim of this dissertation is to describe the conjugacy classes and some of the ordinary irreducible characters of the nite general linear group GL(n, q); together with character tables of some of its subgroups. We study the structure of GL(n, q) and some of its important subgroups such as SL(n, q); UT(n, q); SUT(n, q); Z(GL(n, q)); Z(SL(n, q)); GL(n, q)0 ; SL(n, q)0 ; the Weyl group W and parabolic subgroups P : In addition, we also discuss the groups PGL(n, q); PSL(n, q) and the a ne group A (n, q); which are related to GL(n, q): The character tables of GL(2; q); SL(2; q); SUT(2; q) and UT(2; q) are constructed in this dissertation and examples in each case for q = 3 and q = 4 are supplied. A complete description for the conjugacy classes of GL(n, q) is given, where the theories of irreducible polynomials and partitions of i 2 f1; 2; ; ng form the atoms from where each conjugacy class of GL(n, q) is constructed. We give a special attention to some elements of GL(n, q); known as regular semisimple, where we count the number and orders of these elements. As an example we compute the conjugacy classes of GL(3; q): Characters of GL(n, q) appear in two series namely, principal and discrete series characters. The process of the parabolic induction is used to construct a large number of irreducible characters of GL(n, q) from characters of GL(n, q) for m < n: We study some particular characters such as Steinberg characters and cuspidal characters (characters of the discrete series). The latter ones are of particular interest since they form the atoms from where each character of GL(n, q) is constructed. These characters are parameterized in terms of the Galois orbits of non-decomposable characters of F q n: The values of the cuspidal characters on classes of GL(n, q) will be computed. We describe and list the full character table of GL(n, q): There exists a duality between the irreducible characters and conjugacy classes of GL(n, q); that is to each irreducible character, one can associate a conjugacy class of GL(n, q): Some aspects of this duality will be mentioned

R-Factor: A New Parameter to Enhance Location Accuracy in RSSI based Real-time Location Systems

The fundamental cause of localization error in an indoor environment is fading and spreading of the radio signals due to scattering, diffraction, and reflection. These effects are predominant in regions where there is no-line-of-sight (NLoS) between the transmitter and the receiver. Efficient algorithms are needed to identify the subset of receivers that provide better localization accuracy. © 2009 IEEE