The Nyquist criterion: a useful tool for the robust design of continuous-time ΣΔ modulators

This paper introduces a figure of merit for the robustness of continuous-time sigma-delta modulators. It is based on the Nyquist criterion for the equivalent discrete-time (DT) loop filter. It is shown how continuous-time modulators can be designed by optimizing this figure of merit. This way modulators with increased robustness against variations in the noise-transfer function (NTF) parameters are obtained. This is particularly useful for constrained systems, where the system order exceeds the number of design parameters. This situation occurs for example due to the effect of excess loop delay (ELD) or finite gain bandwidth (GBW) of the opamps. Additionally, it is shown that the optimization is equivalent to the minimization of H_infinity, the maximum out-of-band gain of the NTF. This explains why conventional design strategies that are based on H_infinity, such as Schreier’s approach, provide quite robust modulator designs in the case of unconstrained architectures

Technology development for a low-cost, roll-to-roll chip embedding solution based on PET foils

The aim of the research described in this paper is to develop a low-cost, roll-to-roll compatible process for the realization of electronic systems in foil using chip embedding. The small cost makes these systems suitable for disposable applications as food labels, medicine packages or smart bandages. Surface mount attaching of components on foils is a well-known process for building systems-in-foil. When using low-cost films like PEN and PET, there are serious restrictions on the maximum temperatures that can be used for the surface mounting process (soldering, adhesive bonding). Surface mounting has the additional disadvantage that the components are on the surface of the foil and are therefore not well protected mechanically and physically. The proposed process flow for embedding thin chips in PET foils overcomes these limitations. A key aspect of this technology is the application of a suitable adhesive to encapsulate the chips. The resulting product is based on full-metal copper which has a good thermal and electrical conductivity and allows for fine pitches. The process is compatible with several metal foils (Cu, Al …), offering further possibilities in cost reduction, and does not rely on bumping of the chips or plating of the interconnections to the chips

Antibiotic affects the gut microbiota composition and expression of genes related to lipid metabolism and myofiber types in skeletal muscle of piglets

Background: Early-life antibiotic administration is known to affect gut microbiota and host adiposity, but the effects of antibiotic exposure on skeletal muscle properties remain unknown. The present study evaluated the changes in skeletal muscle properties including myofiber characteristics and composition, as well as intramuscular fat (IMF) content in skeletal muscle of piglets when exposed to a tylosin-containing diet. Results: A total of 18 piglets (28 days of age) were randomly allocated into two groups: control basal diet (Control) and Control + 100 mg tylosin phosphate/kg of feed (Antibiotic). The trial lasted for 39 days. High-throughput amplicon sequencing revealed that no significant difference in initial gut microbiota composition was existed between Control and Antibiotic groups. Antibiotic administration increased body weight and growth rate and decreased feed to gain ratio of pigs (P < 0.05). The carcass lean and fat volumes of pigs were increased by the tylosin administration (P < 0.05). Antibiotic treatment increased myofiber density and the expression of genes related to type I and type IIb myofibers in longissimus muscle (P < 0.05). The IMF content in longissimus muscle was increased by antibiotic exposure (P < 0.05). Antibiotic administration increased expression of genes related to fatty acid uptake and de novo synthesis, and decreased expression of genes related to triglyceride hydrolysis (P < 0.05). Tylosin administration affected taxonomic distribution and beta diversity of the caecal and colonic microbiota of piglets. Conclusion: These results confirm that the growth performance, myofiber composition and muscle lipid metabolism are affected by antibiotic administration, which may be associated with an altered gut microbiota, suggesting that the gut microbiota could be served as a potential target for modulating skeletal muscle properties of host

Overcoming I/O bottleneck in superconducting quantum computing: multiplexed qubit control with ultra-low-power, base-temperature cryo-CMOS multiplexer

Large-scale superconducting quantum computing systems entail high-fidelity control and readout of large numbers of qubits at millikelvin temperatures, resulting in a massive input-output bottleneck. Cryo-electronics, based on complementary metal-oxide-semiconductor (CMOS) technology, may offer a scalable and versatile solution to overcome this bottleneck. However, detrimental effects due to cross-coupling between the electronic and thermal noise generated during cryo-electronics operation and the qubits need to be avoided. Here we present an ultra-low power radio-frequency (RF) multiplexing cryo-electronics solution operating below 15 mK that allows for control and interfacing of superconducting qubits with minimal cross-coupling. We benchmark its performance by interfacing it with a superconducting qubit and observe that the qubit's relaxation times ($T_1$) are unaffected, while the coherence times ($T_2$) are only minimally affected in both static and dynamic operation. Using the multiplexer, single qubit gate fidelities above 99.9%, i.e., well above the threshold for surface-code based quantum error-correction, can be achieved with appropriate thermal filtering. In addition, we demonstrate the capability of time-division-multiplexed qubit control by dynamically windowing calibrated qubit control pulses. Our results show that cryo-CMOS multiplexers could be used to significantly reduce the wiring resources for large-scale qubit device characterization, large-scale quantum processor control and quantum error correction protocols.Comment: 16+6 pages, 4+1+5 figures, 1 tabl

Posture of the arm when grasping spheres to place them elsewhere

Despite the infinitely many ways to grasp a spherical object, regularities have been observed in the posture of the arm and the grasp orientation. In the present study, we set out to determine the factors that predict the grasp orientation and the final joint angles of reach-tograsp movements. Subjects made reach-to-grasp movements toward a sphere to pick it up and place it at an indicated location. We varied the position of the sphere and the starting and placing positions. Multiple regression analysis showed that the sphere's azimuth from the subject was the best predictor of grasp orientation, although there were also smaller but reliable contributions of distance, starting position, and perhaps even placing position. The sphere's initial distance from the subject was the best predictor of the final elbow angle and shoulder elevation. A combination of the sphere's azimuth and distance from the subject was required to predict shoulder angle, trunkhead rotation, and lateral head position. The starting position best predicted the final wrist angle and sagittal head position. We conclude that the final posture of the arm when grasping a sphere to place it elsewhere is determined to a larger extend by the initial position of the object than by effects of starting and placing position. © 2010 Springer-Verlag

Fast and fine-tuned corrections when the target of a hand movement is displaced

To study the strategy in responding to target displacements during fast goal-directed arm movements, we examined how quickly corrections are initiated and how vigorously they are executed. We perturbed the target position at various moments before and after movement initiation. Corrections to perturbations before the movement started were initiated with the same latency as corrections to perturbations during the movement. Subjects also responded as quickly to a second perturbation during the same reach, even if the perturbations were only separated by 60 ms. The magnitude of the correction was minimized with respect to the time remaining until the end of the movement. We conclude that despite being executed after a fixed latency, these fast corrections are not stereotyped responses but are suited to the circumstances

2017 Update of ESC/EAS Task Force on practical clinical guidance for proprotein convertase subtilisin/kexin type 9 inhibition in patients with atherosclerotic cardiovascular disease or in familial hypercholesterolaemia

A correction has been published: European Heart Journal, Volume 39, Issue 22, 7 June 2018, Pages 2105Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017.info:eu-repo/semantics/publishedVersio

Modality and frequency effects in paced serial addition tasks on functional brain networks in healthy controls.

The paced serial addition test (PSAT) is regularly used to assess cognitive deficits in various neuropsychiatric conditions. Being a complex test, it reflects the status of multiple cognitive domains such as working memory, information processing speed and executive functioning. Two versions of the PSAT exist. One uses auditory stimuli through spoken numbers and is known as the PASAT, while the other one presents patients with visual stimuli and is called PVSAT. The PASAT is considered more frustrating by patients, and hence the visual version is usually preferred. Research has suggested that an interference might exist between patients' verbal answers and the auditory presentation of stimuli. We therefore removed the verbal response in this study, and aimed to investigate differences in functional brain activity through functional magnetic resonance imaging. Fifteen healthy controls performed the two test versions inside an MRI scanner - switching between stimulus modality (auditory vs. visual) as well as inter-stimulus frequency (3s vs. 2s). We extracted 11 independent components from the data: attentional, visual, auditory, sensorimotor and default mode networks. We then performed statistical analyses of mean network activity within each component, as well as inter-network connectivity of each component pair during the different task types. Unsurprisingly, we noted an effect of modality on activity in the visual and auditory components. However, we also describe bilateral frontoparietal, anterior cingulate and insular attentional network activity. An effect of frequency was noted only in the sensorimotor network. Effects were found on edges linking visual and auditory regions. Task modality influenced an attentional-sensorimotor connection, while stimulus frequency had an influence on sensorimotor-default mode connections. Scanner noise during functional MRI may interfere with brain activation - especially during tasks involving auditory pathways. The question whether to use PVSAT or PASAT for an fMRI study is, therefore, an important one. Specific effects of both modalities should be known to study designers. We conclude that both tests should not be considered interchangeable, as significant changes were brought to light during test performance in different modalities. Included here are pre-processed MRI data (realignment, slice timing correction, affineing coregistration with structural T1 images, segmentation, normalisation into the standard Montreal Neurological Institute (MNI) space, and spatial smoothing with a Gaussian kernel of 8 mm full width at half-maximum), done with SPM, of 15 subjects, in 4D nifti files