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Deep unfolding is a very promising concept that allows to combine the advantages of traditional estimation techniques, such as adaptive filters, and machine learning approaches, like artificial neural networks. Focusing on a challenging self‐interference problem occurring in frequency‐division duplex radio frequency transceivers, namely modulated spurs, it is shown that deep unfolding enables remarkable performance gains. Based on the hyper‐parameter optimisation of several least‐mean squares (LMS) variants and the recursive‐least squares algorithm, the importance of a well‐chosen loss function are highlighted. Especially the variable step‐size LMS and the transform‐domain LMS vastly benefit without increased runtime complexity. [ABSTRACT FROM AUTHOR]

The stochastic gradient descent (SGD) method is one of the most prominent first‐order iterative optimisation algorithms, enabling linear adaptive filters as well as general nonlinear learning schemes. It is applicable to a wide range of objective functions, while featuring low computational costs for online operation. However, without a suitable step‐size normalisation, the convergence and tracking behaviour of the stochastic gradient descent method might be degraded in practical applications. In this letter, a novel general normalisation approach is provided for the learning of (non‐)holomorphic models with multiple independent parameter sets. The advantages of the proposed method are demonstrated by means of a specific widely‐linear estimation example. [ABSTRACT FROM AUTHOR]

In this study, we performed a survey of infantile and late-onset Pompe disease (IOPD and LOPD) in Austria. Paediatric and neuromuscular centres were contacted to provide a set of anonymized clinical and genetic data of patients with IOPD and LOPD. The number of patients receiving enzyme replacement therapy (ERT) was obtained from the pharmaceutical company providing alglucosidase alfa. We found 25 patients in 24 families, 4 IOPD and 21 LOPD with a resulting prevalence of 1:350,914. The most frequent clinical manifestation in LOPD was a lower limb-girdle phenotype combined with axial weakness. Three patients were clinically pauci- or asymptomatic and were diagnosed because of persistent hyperCKemia. Diagnostic delay in LOPD was 7.4 ± 9.7 years. The most common mutation was c.-32-13T > G. All IOPD and 17 symptomatic LOPD patients are receiving ERT. Standardized follow-up was only available in six LOPD patients for the 6-min walk test (6minWT) and in ten for the forced vital capacity (FVC). Mean FVC did not decline (before ERT; 63.6 ± 39.7%; last evaluation during ERT: 61.9 ± 26.9%; P = 0.5) while there was a trend to decline in the mean distance covered by the 6minWT (before ERT: 373.5 ± 117.9 m; last evaluation during ERT: 308.5 ± 120.8 m; P = 0.077). The study shows a lower prevalence of Pompe disease in Austria than in other European countries and corroborates a limb-girdle phenotype with axial weakness as the most common clinical presentation, although asymptomatic hyperCKemia may be the first indication of LOPD. [ABSTRACT FROM AUTHOR]

Background: Natalizumab is the first monoclonal antibody therapy approved for multiple sclerosis (MS). Its therapeutic mechanism is the blockade of the α4-integrin subunit of the adhesion molecule (AM) very late activation antigen-4 (VLA-4), which leads to an inhibition of immune cell extravasation into the central nervous system (CNS).Methods: We investigated changes in the expression levels of unblocked α4-integrin and further AM (intercellular adhesion molecule-1, -2, -3 (cICAM-1, -2, -3), leukocyte function associated antigen-1 (LFA-1)) on peripheral blood mononuclear cells (PBMC) determined by flow cytometry from 25 patients with MS before the first natalizumab infusion and before the fourth infusion. In 15 MS patients AM expression was evaluated every 3 months over 1 year.Results: We found a significant decrease (p < 0.0001) of unblocked α4-integrin cell surface expression on all investigated PBMC subsets (T cells —61.7%, B cells —69.1%, monocytes/macrophages —46.4%) in the blood of MS patients after 3 months of natalizumab treatment. Moreover, a continuous decrease (p < 0.05) of unblocked α4-integrin expression levels was seen after 3, 6, 9, and 12 months. As a secondary effect, expression levels of the other investigated AM were differentially affected.Conclusions: Results show a sustained decrease of unblocked α4-integrin expression not only in all patients but also in all investigated PBMC subsets. This probably results in a continuously decreasing transmigration of PBMC into the CNS and may explain the improved clinical efficacy in the second treatment year and also the increasing risk of progressive multifocal leukoencephalopathy during long-term natalizumab therapy. We conclude that AM expression profiles are promising candidates for the development of a biomarker system to determine both natalizumab treatment response and patients at risk for opportunistic CNS infections. [ABSTRACT FROM AUTHOR]

Signals transmitted over a multi-path propagation channel exhibit Inter-Path Interference (IPI) and fading. The receiver has to employ measures to mitigate these effects or it will incur severe performance degradation. A classic approach in Code Division Multiple Access (CDMA) communications is the Rake receiver. Alternatively, a Linear Minimum Mean Square Error (LMMSE) equalizer can further improve performance. This paper compares performance and computational complexity of these two algorithms. A hybrid solution will be introduced in order to decrease computational complexity while retaining most of the interference suppression capabilities of the LMMSE equalizer. [ABSTRACT FROM AUTHOR]

The application of an equalisation method for mobile station terminals using particle filters is presented. To use particle filters for equalisation, a mathematical model is shown which allows the transmitted symbols to be represented as the state of a stochastic system, which can be estimated by particle filters. The authors propose an equaliser structure with particle filters for application in mobile station receivers, especially for GSM/EDGE (Global System for Mobile Communications/Enhanced Data Rate for GSM Evolution). Several improvement strategies, which help to obtain better estimation results with a lower number of particles, are discussed. In addition, performance evaluations of the particle filter equaliser for GSM/EDGE are presented. [ABSTRACT FROM AUTHOR]

Describes the edge position modulation with run-length-limited coding for high-speed wireless infrared communications. Increase in bandwidth efficiency; Power efficiency; Maintenance of low bit-error rates; Optimization of the characteristics of the wireless infrared channel.

Driven by the Infrared Data Association, wireless infrared communication has become a very popular and widely used method for short-range data transmission between mobile devices like laptops, PDAs, and mobile phones. Especially in ad hoc connection applications, IrDA excels over radio-based solutions like Bluetooth or cable-based solutions like USB, due to the point-and-shoot characteristic of infrared communication. The quality and speed of infrared communications are mainly limited by the bandwidth of infrared transceivers. Therefore, it is important to use a modulation technique with high bandwidth efficiency, while simultaneously maintaining a low bit error rate and high power efficiency. Consequently, the IrDA has continuously improved the modulation techniques of its standards by introducing return to zero inverted (RZI) for the serial infrared (SIR) mode, 4-PPM for the fast infrared mode, and HHH(1,13) for the latest very fast infrared mode. This article presents a new modulation scheme called edge position modulation (EPM) with RLL coding, which offers increased bandwidth efficiency over the previous methods and attractive power efficiency. Since the novel modulation technique can be optimized to the characteristics of the wireless infrared channel, it also maintains low bit error rates. [ABSTRACT FROM PUBLISHER]

A novel polynomial-enhanced open-circuit voltage extrapolation method is presented. It is used to identify a battery's state-of-charge based on the estimation of the corresponding relaxation voltage. The proposed method represents the relaxation process via a polynomial enhanced voltage model, calculated by least squares estimation. Compared to state-of-the-art models, the proposed approach reduces the period of time needed until the state-of-charge can be accurately determined. For the particular cell under test, an open-circuit voltage accuracy of ±1 can be reached within the first 11 minutes of the relaxation process. In addition, the reduced estimation time also leads to a lower power consumption of an integrated circuit-based battery identification solution. [ABSTRACT FROM AUTHOR]

Unlabelled: A 6-year-old female patient presented with a rapidly progressive scleroderma-like syndrome involving almost the entire integument. Initially clinical patterns and histopathological data of both eosinophilic fasciitis and scleredema adultorum were present. The course of the disease remained unusual for both conditions but finally argued in favour of the diagnosis of eosinophilic fasciitis.Conclusion: Eosinophilic fasciitis and scleredema adultorum might be subtypes of one disease entity. [ABSTRACT FROM AUTHOR]

Presented is a digital controller to regulate a point-of-load Buck converter. The regulator varies both the duty cycle, as well as the switching frequency, by controlling not only the on-time, but also the off-time of the switching period. The multi-loop digital controller, which achieves a tight voltage regulation and an excellent dynamic performance, is presented and its effectiveness is proven by means of experimental results. The controller architecture, together with an analogue-to-digital converter, has been integrated in a 0.13 µm CMOS technology. [ABSTRACT FROM AUTHOR]

For decoding of LDPC codes two types of algorithms are frequently discussed in the literature. One type is based on belief propagation (BP) the other is based on linear programming (LP). Especially for short LDPC codes it has been observed that BP decoding often performs better at low SNR ranges, whereas LP decoding performs better at high SNR levels. A combined linear programming and belief propagation decoder is presented, which significantly outperforms both a pure LP and a pure BP decoder throughout the whole SNR range. [ABSTRACT FROM AUTHOR]

Presents a letter to the editor related to nutritional infantile vitamin B12 deficiency.

A non-classical clinical course of Barth Syndrome (BTHS) A six year-old boy, born to non-consanguineous, healthy parents was primarily referred because of growth retardation. Auxological parameters were below the 3rd percentile after having been normal at birth. Especially the extent of microcephaly (<3 SD) was impressive. Additionally, mild generalized muscular hypotonia was present. Psychomotor development was regular. Gastrointestinal, endocrinological and nutritional workup revealed no explanatory pathological findings. Metabolic workup including lactate profile, pyruvate and lactate/pyruvate ratio was normal. MRI of the brain and MR-spectroscopy showed no pathologies. Eighteen months later the patient presented with episodes of painless muscular weakness and severe exercise intolerance triggered by a febrile infection. Clinical findings included muscular weakness, hypotonia and positive Gower's sign in the absence of muscular atrophy. Diagnostic workup again was unremarkable. The combination of unclear muscular symptoms and persistent growth retardation prompted mitochondrial workup. Activity of complex I, III and IV in oxidative phosphorylation was reduced. Whole exome sequencing revealed a mutation in the tafazzine gene described as associated with early onset, severe BTHS. The diagnosis of BTHS was supported by a specific pattern of fatty acid profile of cardiolipin. Nevertheless, characteristic signs and symptoms for BTHS such as cardiomyopathy, neutropenia or 3-methylglutaconic aciduria have never been observed in the patient. Conclusion Regarding our patient we would recommend testing for BTHS even by an incomplete phenotype like growth retardation and muscular symptoms. Otherwise this potentially life-threatening inborn error of metabolism is likely to be underdiagnosed. The novel method for cardiolipin analysis by UPLC-MS shows 100% sensitivity and specificity for BTHS, making it a reliable screening-test. Abnormal cardiolipin ratio testing can be followed by genetic testing for TAZ-mutations. An early diagnosis of BTHS showed a marked increase in lifespan and quality of life due to appropriate supportive management. [ABSTRACT FROM AUTHOR]

Researchers from the University of Klagenfurt in Austria tell us why it is becoming crucial to be able to accurately monitor a battery's state-of-charge, and how their latest work can help. [ABSTRACT FROM AUTHOR]