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Following the report of an excess in paediatric cases of severe acute hepatitis of unknown aetiology by the United Kingdom (UK) on 5 April 2022, 427 cases were reported from 20 countries in the World Health Organization European Region to the European Surveillance System TESSy from 1 January 2022 to 16 June 2022. Here, we analysed demographic, epidemiological, clinical and microbiological data available in TESSy. Of the reported cases, 77.3% were 5 years or younger and 53.5% had a positive test for adenovirus, 10.4% had a positive RT-PCR for SARS-CoV-2 and 10.3% were coinfected with both pathogens. Cases with adenovirus infections were significantly more likely to be admitted to intensive care or high-dependency units (OR = 2.11; 95% CI: 1.18–3.74) and transplanted (OR = 3.36; 95% CI: 1.19–9.55) than cases with a negative test result for adenovirus, but this was no longer observed when looking at this association separately between the UK and other countries. Aetiological studies are needed to ascertain if adenovirus plays a role in this possible emergence of hepatitis cases in children and, if confirmed, the mechanisms that could be involved.

International audience; Microbes have been coevolving with their host for millions of years, exploiting host resources to their own benefit. We show that viral and bacterial pathogens convergently evolved to hijack cellular mitogen-activated protein kinase (MAPK) p90-ribosomal S6-kinases (RSKs). Theiler’s virus leader (L) protein binds RSKs and prevents their dephosphorylation, thus maintaining the kinases active. Recruitment of RSKs enables L-protein-mediated inhibition of eukaryotic translation initiation factor 2 alpha kinase 2 (EIF2AK2 or PKR) and stress granule formation. Strikingly, ORF45 protein of Kaposi’s sarcoma-associated herpesvirus (KSHV) and YopM protein of Yersinia use the same peptide motif as L to recruit and activate RSKs. All three proteins interact with a conserved surface-located loop of RSKs, likely acting as an allosteric regulation site. Some unrelated viruses and bacteria thus evolved to harness RSKs in a common fashion, yet to target distinct aspects of innate immunity. As documented for Varicella zoster virus ORF11, additional pathogens likely evolved to hijack RSKs, using a similar short linear motif

The investigation deals with the specific behavior of tire and new half-track based tractor chassis concepts under pull-condition, where horizontal and vertical forces occur between tractor and implement. These forces lead to a change of the front- and rear axle loads, compared to non-pull condition. The pulling forces lead to a pitch effects of the tractor and can also result in a pitch effect of the track system, depending on the design of the track system. This effect can lead to an uneven contact pressure in the belt-soil contact. To evaluate the pitch effect and the risk of soil compaction, measurements of the ground pressure with “Bolling Sensors” have been carried out to indicate the effect of the pulling forces to the tractor chassis and the soil pressure. The investigation of the ground pressures have been done in a comparison of a standard tractor Axion 960 and two half-track tractors Axion 960 with the CLAAS TerraTrac and CASE-IH Magnum 380 Rowtrac with triangle tracks under pulling conditions with specific ballasting configurations. The investigation of the pulling behavior of the tractors have been executed as a comparison of two Axion 960 tractors, one in standard tire version and the other as half-track version. Both tractors have the same configuration of engine-power and transmission configuration with CVT transmission. The results are, that the CLAAS TerraTrac track system features a significant reduced soil pressure in no-pull and also in pull-condition in comparison to standard tires. Also in comparison to a triangle track system with positive drive principle the soil pressure of the CLAAS TerraTrac system with the suspension is much lower. The comparison of pulling performance shows an improved pulling potential at speeds < 10kph of the TerraTrac system compared to the tired tractor. At higher speeds, the tire-soil contact is not the limiting factor and so wheeled and track-typed tractor show a similar pulling performance.

Accumulating evidence indicates that motor neuron degeneration in amyotrophic lateral sclerosis (ALS) is a non-cell-autonomous process and that impaired glutamate clearance by astrocytes, leading to excitotoxicity, could participate in progression of the disease. In astrocytes derived from an animal model of ALS (hSOD1G93A rats), activation of type 5 metabotropic glutamate receptor (mGluR5) fails to increase glutamate uptake, impeding a putative dynamic neuroprotective mechanism involving astrocytes. Using astrocyte cultures from hSOD1G93A rats, we have demonstrated that the typical Ca2+ oscillations associated with mGluR5 activation were reduced, and that the majority of cells responded with a sustained elevation of intracellular Ca2+ concentration. Since the expression of protein kinase C epsilon isoform (PKCɛ) has been found to be considerably reduced in astrocytes from hSOD1G93A rats, the consequences of manipulating its activity and expression on mGluR5 signaling and on the regulation of glutamate uptake have been examined. Increasing PKCɛ expression was found to restore Ca2+ oscillations induced by mGluR5 activation in hSOD1G93A -expressing astrocytes. This was also associated with an increase in glutamate uptake capacity in response to mGluR5 activation. Conversely, reducing PKCɛ expression in astrocytes from wild-type animals with specific PKCɛ-shRNAs was found to alter the mGluR5 associated oscillatory signaling profile, and consistently reduced the regulation of the glutamate uptake-mediated by mGluR5 activation. These results suggest that PKCɛ is required to generate Ca2+ oscillations following mGluR5 activation, which support the regulation of astrocytic glutamate uptake. Reduced expression of astrocytic PKCɛ could impair this neuroprotective process and participate in the progression of ALS.

Some European countries recently reported an increase in hepatitis E virus genotype 3 (HEV-3) of the subtype 3c. No link between HEV-3 subtypes and severity is established to date. Here, we report that patients infected with HEV-3c were at lower risk of hospitalisation, compared to those infected with HEV-3f, the other main subtype circulating in Belgium.

The investigation deals with the specific behavior of tire and new half-track based tractor chassis concepts under pull-condition, where horizontal and vertical forces occur between tractor and implement. These forces lead to a change of the front- and rear axle loads, compared to non-pull condition. The pulling forces lead to a pitch effects of the tractor and can also result in a pitch effect of the track system, depending on the design of the track system. This effect can lead to an uneven contact pressure in the belt-soil contact. To evaluate the pitch effect and the risk of soil compaction, measurements of the ground pressure with “Bolling Sensors” have been carried out to indicate the effect of the pulling forces to the tractor chassis and the soil pressure. The investigation of the ground pressures have been done in a comparison of a standard tractor Axion 960 and two half-track tractors Axion 960 with the CLAAS TerraTrac and CASE-IH Magnum 380 Rowtrac with triangle tracks under pulling conditions with specific ballasting configurations. The investigation of the pulling behavior of the tractors have been executed as a comparison of two Axion 960 tractors, one in standard tire version and the other as half-track version. Both tractors have the same configuration of engine-power and transmission configuration with CVT transmission. The results are, that the CLAAS TerraTrac track system features a significant reduced soil pressure in no-pull and also in pull-condition in comparison to standard tires. Also in comparison to a triangle track system with positive drive principle the soil pressure of the CLAAS TerraTrac system with the suspension is much lower. The comparison of pulling performance shows an improved pulling potential at speeds < 10kph of the TerraTrac system compared to the tired tractor. At higher speeds, the tire-soil contact is not the limiting factor and so wheeled and track-typed tractor show a similar pulling performance.

Accumulating evidence indicates that motor neuron degeneration in amyotrophic lateral sclerosis (ALS) is a non-cell-autonomous process and that impaired glutamate clearance by astrocytes, leading to excitotoxicity, could participate in progression of the disease. In astrocytes derived from an animal model of ALS (hSOD1

A critical role has been assigned to protein kinase C (PKC)e in the control of intracellular calcium oscillations triggered upon activation of type 5 metabotropic glutamate receptor (mGluR5) in cultured astrocytes. Nevertheless, the physiological significance of this particular signalling profile in the response of astrocytes to glutamate remains largely unknown. Considering that kinases are frequently involved in the regulation of G protein-coupled receptors, we have examined a putative link between the nature of the calcium signals and the response regulation upon repeated exposures of astrocytes to the agonist (S)-3,5-dihydroxyphenylglycine. We show that upon repeated mGluR5 activations, a robust desensitization was observed in astrocytes grown in culture conditions favouring the peak-plateau-type response. At variance, in cell cultures where calcium oscillations were predominating, the response was fully preserved even during repeated challenges with the agonist. Pharmacological inhibition of PKCe or genetic suppression of this isoform using shRNA was found to convert an oscillatory calcium profile to a sustained calcium mobilization and this latter profile was subject to desensitization upon repetitive mGluR5 activation. Our results suggest a yet undocumented scheme in which the activity of PKCe contributes to preserve the receptor sensitivity upon repeated or sustained activations. Cover Image for this issue: doi: 10.1111/jnc.13797.

Introduction Teamwork is a developed skill that is essential within pharmacy practice and health care. Exposure to team-based learning (TBL) pedagogy may foster development of this skill. The purpose of this study was to evaluate a measure for perception of teamwork among PharmD students, and then examine a module using TBL pedagogy. Methods Faculty instructors for a 90-contact hour cardiovascular pharmacotherapy module used TBL pedagogy in teaching 18 hours of the therapeutics topics in that module. To determine a change in their perceptions of teamwork, second-year PharmD students took pre- and post-module surveys. The survey instrument used was previously published with use among medical students. Results Fifty-eight of 61 PharmD students participated. The Rasch Measurement Model was used to construct measures of student perceptions along a linear and unidimensional "perception of teamwork" continuum. To make the survey unidimensional, seven of the 20 items were removed. The resulting instrument had a reliability of 0.93 and separation of 3.56. Pre-module survey results were 1.1 ± 2.5 logits, whereas afterwards were 1.3 ± 2.4 logits. Change in students' perceptions were varied at 0.2 ± 2.6 logits (paired t -test p = 0.6293). Older students had a negative correlation ( r = –0.27, p = 0.04), whereas pharmacy work experience had a positive correlation with change in teamwork perception ( r = 0.31, p = 0.02). Conclusion This instrument appears psychometrically valid and reliable to measure changes in PharmD students' perceptions of teamwork with TBL. Study results led to reflection on attributing factors for module improvements by involved faculty.

Digital subscriber line (DSL) technology allows copper access network operators to offer high-speed links at a reasonable cost. The optimization of the DSL network is a cumbersome task due to the abundance of physical layer configuration parameters and significant differences between lines with respect to interference and attenuation. This paper discusses concepts for dynamic optimization techniques that trade off rate, latency, stability, and power usage in an automated and transparent fashion. The techniques use an initial configuration selection to swiftly obtain a near-optimal configuration and then proceed to acquire additional statistics on noise and interference in order to be able to fine-tune the configuration and gradually increase performance. Optimization results for a DSL network that is carrying video services are presented by aid of the Dynamic Line Management module in the Alcatel-Lucent 5530 Network Analyzer.

Downstream (DS) crosstalk channels of digital subscriber line systems can be estimated based on the reported signal-to-noise ratio (SNR). In the case of an already active victim line (VL) impacted by the joining of a new disturber line (DL), sending perturbing signals on the VL and reporting the SNRs allow the estimation of the crosstalk channel from the DL to the VL. This paper generalizes that concept to include full startup, tracking and joining scenarios as well as the impact of different perturbation signal choices. Additionally, the sensitivity of the algorithm to different sources of imperfection is analyzed. Simulation results reveal that starting without precoding, and updating the precoder matrix based on the DS crosstalk channel estimates, the far-end crosstalk-free SNR can be reached in a limited number of iterations (e.g., 36 SNR measurements are needed for the four lines case). The SNR-assisted method is documented in an informative appendix of the draft G.vector recommendation as a backward compatible method for very high speed digital subscriber lines (VDSL2) and, hence, can be used for channel acquisition today.

To gradually expand their networks, operators deploy new xDSL technologies from remote terminals (RT's) closer to the customer. However, since xDSL lines deployed from an RT can share a binder with lines deployed from the central office (CO), a near-far problem is introduced and crosstalk may cause a severe performance degradation for the CO-deployed lines. RT lines have to be careful about how to allocate transmit power to the transmission frequencies, such that the impact on the CO lines is acceptable. Noise impact (NI) methods have been proposed based on a target noise shape generated by the disturbers (RT lines). In this paper new methods based on the actual impact on the bit rate of the victims (CO lines) are proposed. These bit impact (BI) methods closely approximate the optimal power allocation.

We present direct measurements of the spatial coherence area of a pulsed broad-area vertical-cavity surface-emitting laser using a reversing wavefront interferometer. With this technique, we can assess the size and uniformity of the coherence area across the laser aperture, being of importance for projection applications. We show that the output beam can be considered quasi-homogeneous and that the measured coherence area corresponds well with the coherence area deduced from the far-field emission profile. We demonstrate that the coherence area is limited in size by the radial temperature gradient in the device and discuss the origin of coherence variations.

Faced with fierce competition from cable operators, telephone companies are now aggressively investing in digital subscriber line technology with the objective of providing an economic broadband access alternative. However, high-bit-rate transmissions over the metallic access network is far from trivial. The subscriber loop predominantly consists of interconnection of twisted pair copper sections. This causes severe attenuation of the high-frequency components of the transmitted signal. Equalization refers to the signal processing in the transceiver to combat the effects of the dispersive channel on the transmitted signal. This article overviews equalization methods for discrete multitone modulation (DMT). The interference structure created by a non-ideally equalized channel is analyzed. Time modulation as well as frequency domain equalization methods are addressed.

The twisted pair copper access network was originally intended as a transmission medium for low-bandwidth analog voice signals. Unlike voiceband modems that operate in this frequency band, emerging high-speed digital transmission systems like ADSL and VDSL use a much larger spectrum. Because VDSL signals contain frequencies up to several megahertz, these broadband signals are susceptible to more hostile noise conditions. This article identifies the different noise impairments and shows how their effect can be mitigated in multicarrier-based VDSL systems.

In a digital transmission system, synchronization is an essential receiver function. Accurate timing information must be known to the demodulator in order to produce reliable estimates of the transmitted data sequence. In this article, synchronization for discrete multitone transmission (DMT) is examined. The effect of imperfect timing on the receiver performance is investigated. An overview of timing estimation and correction circuits based on data-aided and non-data-aided algorithms derived from maximum-likelihood estimation theory is given.

Background: Several experimental studies have suggested potential anticarcinogenic effects of flavonoids, although epidemiologic evidence for the impact of dietary flavonoids on risk of gastric cancer (GC) is limited. Objective: We investigated the association between intake of dietary flavonoids and lignans and incident GC. Design: The study followed 477,312 subjects (29.8% men) aged 35-70 y from 10 European countries who participated in the European Prospective Investigation into Cancer and Nutrition (EPIC) study. Validated dietary questionnaires and lifestyle information were collected at baseline. A food-composition database on flavonoids and lignans was compiled by using data from USDA and Phenol-Explorer databases. Results: During an average follow-up of 11 y, 683 incident GC cases (57.8% men) were mostly validated by a panel of pathologists and used in this analysis. We observed a significant inverse association between total flavonoid intake and GC risk in women (HR: 0.81; 95% CI: 0.70, 0.94; for the continuous variable after log2 transformation) but not in men (HR: 0.97; 95% CI: 0.85, 1.09). in women, significant inverse associations with GC risk were also observed for intakes of some flavonoid subgroups (anthocyanidins, flavonols, flavones, and flavanols), particularly with intestinal type tumors for total flavonoid and flavanol intakes (P-heterogeneity < 0.1). After stratification by smoking status and sex, there was no significant heterogeneity in these associations between ever- and never-smokers. Conclusion: Total dietary flavonoid intake is associated with a significant reduction in the risk of GC in women. Am J Clin Nutr 2012;96:1398-408.

Recently, it has been shown that spectral optimization in copper access networks can significantly reduce the transmit power required, resulting in significant reductions in the line driver energy consumption. Building on these results, we develop an improved model for line driver power usage which focuses on the aggregate transmit power, the supply voltage, and on constraints that connect these two. We show that an ideally tuned supply voltage can save significant power relative to a fixed supply voltage. Much of these gains may be achievable with a small set of discrete supply voltage options. The line driver model is simple enough to incorporate into a full spectral optimization framework, in which line driver power usage and rate are traded-off in a utility-based optimization framework. Benefits of power supply tuning in combination with spectral optimization are illustrated in numerical examples.

It has been shown recently that power-efficient digital subscriber line (DSL) access networks can be designed via an optimization problem with an objective that assigns a value to user's data rate while assessing a penalty proportional to the line driver energy consumption. An optimization algorithm was proposed that combines elements of linear programming and trust region optimization, having a complexity that scales linearly with the number of users and the number of used tones. Motivated by the expansion of DSL technology from hundreds to thousands of tones, and by operator's preference to implement power spectral profiles that can be specified with a small number of parameters, we propose in this paper a reduced dimensional formulation of the optimization problem. The new formulation reduces complexity with little loss in performance, by exploiting the smoothness of the problem data as a function of frequency. Using the new formulation, we compare the efficiency achievable using two classes of line drivers: class AB and class G.

The key driver for bandwidth today, and in the coming years will clearly be video. During the talk, advances in video technology and a myriad of new emerging video applications will be presented. Article not available.

Traditionally, dynamic spectrum management (DSM) deals with the rate maximization of digital subscriber lines subject to a per modem total transmit power constraint. Motivated by the desirability of reducing total power consumption, we reformulate the problem as one of minimizing the transmit power subject to minimum target rates. Both versions of the problem are special cases of a unified framework in which both rate maximization and power minimization are objectives. We also consider less complex formulation where a flat power backoff is applied relative to a fixed power profile.

A statistical model has been constructed that extends the phenomenological 99% cumulant model to a full cumulative distribution function for amplitude and phase of the far end crosstalk between twisted pair telephone wires. The offset of the crosstalk amplitude relative to the 99% level is described by a frequency independent beta distribution. Inter-binder crosstalk is modeled by an additional parameter that reflects the distance between the two binders. The multi-line behavior of the beta model is shown to be close to the currently agreed scaling factor without additional forcing.

In this paper we investigate the tracking performance of the downstream (DS) crosstalk (XT) channel estimation based on the reported signal to noise ratio (SNR), in particular for digital subscriber line (DSL) systems. Aiming to its simplicity, the SNR-assisted XT estimation, has been recognized in ITU as a backward compatible method that does not require any change in the very high speed digital subscriber line 2 (VDSL2) standard. This low complex algorithm can be used for XT channel estimation in dynamic spectrum management (DSM) techniques today. The algorithm as proposed recently, relies on sending perturbing signals on the victim lines (VLs) and reporting the SNRs by those lines to acquire the crosstalk channel from some disturber line (DL) to the VLs. We generalize this concept to include full startup, tracking and joining scenarios as well as the impact of different perturbation signal choices. Simulation results reveal that starting from no crosstalk precompensation, and updating a precoder matrix based on the DS crosstalk channel estimates, the far-end crosstalk (FEXT) free SNR can be reached in few iterations (36 SNR measurements for the four lines case).

Rapid acquisition of accurate crosstalk estimates is a core requirement for effective preceding in digital subscriber line (DSL) systems. It is shown that signal-to-noise ratio (SNR) reports provided by customer premises equipment (CPE) can be used to perform this task by "tuning" the precoder, i.e., iterating alternate steps of estimation and precoder adaptation. Such an approach has the advantage that it can be applied to legacy CPEs. Estimation algorithms are designed using techniques from stochastic control.

We present experiments measuring the complex degree of coherence of a Broad-Area Vertical-Cavity Surface-Emitting Laser (BA-VCSEL) when it is driven into a regime of spatially incoherent emission. This high-power, spatially incoherent emission regime is quite uncommon for semiconductor lasers but can be useful in e.g. illumination and projection systems, as the low degree of spatial coherence may help to reduce speckle. The near-field coherence properties are measured for different positions in the VCSEL's aperture using a 180 degrees reversing-wavefront Michelson interferometer. We give evidence that the coherence area is much smaller than the VCSEL's aperture and that the intensity fluctuations across the coherence area are small, therefore allowing the BA-VCSEL to be considered a quasi-homogeneous source. We explain the reason for the relatively small coherence radius of about 1.4 μm based on the mode size in a planar cavity together with the thermal gradient within the VCSEL aperture.

Vertical Cavity Surface Emitting Lasers (VCSELs) often present switching between two orthogonal polarization states when varying parameters like e.g. current or temperature. Around such a switching point, the system randomly jumps between these two polarization states (mode hopping), driven by noise. In this contribution, we present experimental and numerical results showing the effect of coloured noise, externally added to the current, on the switching characteristics of a VCSEL.

An overview of the idiosyncratic emission characteristics of pulsed broad-area VCSELs is presented, together with a statistical model which describes these devices as quasi-homogeneous sources. The predicted properties of such sources, which include two reciprocity relations between near and far field aspects of the cross-spectral density as well as its propagation, are verified experimentally. We finish by showing how and which thermal effects are at the origin of this nonmodal emission.

We develop a rate equation model describing the polarization switching phenomenon in vertical-cavity surface-emitting lasers taking into account the major underlying physical origins of this behavior: spin flip relaxation effects, temperature variations and both residual strain in the quantum well and stresses externally applied to the device. To include effects of temperature and stress or strain, we describe the optical material properties of the quantum well by way of a recently derived analytical approximation for the optical susceptibility of uniaxially stressed quantum-well lasers at low temperatures. We review the influence of temperature and stress on the polarization-dependent gain and the linewidth enhancement factor. Combining this information with cavity anisotropies and spin carrier dynamics, we present a model that provides a unified overview of the polarization switching phenomenon. By way of a linear stability analysis, the polarization mode stability is discussed and compared with earlier experimental results.

We find experimentally that the relaxation oscillation peak in the relative intensity noise spectrum of a semiconductor laser has a higher damping and lower frequency when we add low frequency noise to the pump current. The broadening of the relaxation oscillation peak with increasing carrier noise level is interpreted as an increase of the nonlinear gain compression with noise strength.

We derive an analytical approximation for the gain of stressed quantum well lasers at low temperatures. This enables us to unify stress, thermal and spin relaxation effects in one model describing the polarization properties of VCSELs.

This paper studies the effect of a Kerr-type nonlinear defect in an anisotropic photonic crystal and shows the resulting polarisation bistability as well as different regimes of operation.

We discuss the effect of uniaxial planar stress on polarization switching in vertical-cavity surface-emitting lasers (VCSELs). The approach is based on an explicit form of a frequency-dependent complex susceptibility of the uniaxially stressed quantum-well semiconductor material. In this mesoscopic framework, we have taken cavity anisotropies, spin carrier dynamics, and thermal shift of the gain curve into account. In this way, we present a model that provides a global overview of the polarization switching phenomenon. The results are compared with experiments on an air-post VCSEL operating at 980 nm.

In semiconductor lasers, spontaneous recombination of electrons and holes results in two types of noise contribution to the laser output field: spontaneous emission noise due to a fraction of spontaneously emitted photons ending up in the lasing mode, referred to as field noise, and carrier or inversion noise due to the discrete, random and instantaneous character of each recombination event. Henry showed [1] that the carrier noise has no influence on the static properties of a cw-emitting semiconductor laser and little influence on the dynamic properties. This has led to the general belief that carrier noise can be ignored in the analysis of semiconductor lasers. In this contribution we present a systematic study of the effect of an extra current noise source added to the low-noise current injection source of a thermally stabilized VCSEL. We have checked the laser features when varying the injected noise level and report changes on the shape and position of the relaxation oscillation peak in the relative intensity noise: the width Ωof the peak increases while the position Ω shifts to lower frequencies, the sum Ω2+ Ω2 remaining essentially constant (see figure). We have carried out an analytical study of a set of simple rate equations for a typical semiconductor laser. On that basis we conjecture that the carrier noise is responsible for a change in the nonlinear gain saturation due to spatial effects.

Switching between two orthogonal linear polarisations in the fundamental mode of vertical-cavity surface-emitting lasers is the object of intensive experimental and theoretical work. Although several models have been proposed, experimental evidence suggests that gain/loss differences between the two modes is an important factor in polarisation switching. However, this view has never been mathematised. In this contribution we study analytically and numerically a class of simple intensity rate equations for a semiconductor laser with two nearly degenerate modes. In our model, the gain is current dependent to describe the gain shift relative to the cavity modes.