We show that quantum circuits where the initial state and all the following quantum operations can be represented by positive Wigner functions can be classically efficiently simulated. This is true ...both for continuous-variable as well as discrete variable systems in odd prime dimensions, two cases which will be treated on entirely the same footing. Noting the fact that Clifford and Gaussian operations preserve the positivity of the Wigner function, our result generalizes the Gottesman-Knill theorem. Our algorithm provides a way of sampling from the output distribution of a computation or a simulation, including the efficient sampling from an approximate output distribution in the case of sampling imperfections for initial states, gates, or measurements. In this sense, this work highlights the role of the positive Wigner function as separating classically efficiently simulable systems from those that are potentially universal for quantum computing and simulation, and it emphasizes the role of negativity of the Wigner function as a computational resource.
To review the scientific literature related to the safe handling of hazardous drugs (HDs).
Critical analysis of works retrieved from MEDLINE, the Cochrane Library, Scopus, CINHAL, Web of Science and ...LILACS using the terms "Hazardous Substances", "Antineoplastic Agents" and "Cytostatic Agents", applying "Humans" and "Guidelines" as filters. Date of search: January 2017.
In total, 1100 references were retrieved, and from those, 61 documents were selected based on the inclusion and exclusion criteria: 24 (39.3%) documents related to recommendations about HDs; 27 (44.3%) about antineoplastic agents, and 10 (33.3%) about other types of substances (monoclonal antibodies, gene medicine and other chemical and biological agents). In 14 (23.3%) guides, all the stages in the manipulation process involving a risk due to exposure were considered. Only one guide addressed all stages of the handling process of HDs (including stages with and without the risk of exposure). The most described stages were drug preparation (41 guides, 67.2%), staff training and/or patient education (38 guides, 62.3%), and administration (37 guides, 60.7%). No standardized informatics system was found that ensured quality management, traceability and minimization of the risks associated with these drugs.
Most of the analysed guidelines limit their recommendations to the manipulation of antineoplastics. The most frequently described activities were preparation, training, and administration. It would be convenient to apply ICTs (Information and Communications Technologies) to manage processes involving HDs in a more complete and simpler fashion.
We introduce a framework of optomechanical systems that are driven with a mildly amplitude-modulated light field, but that are not subject to classical feedback or squeezed input light. We find that ...in such a system one can achieve large degrees of squeezing of a mechanical micromirror--signifying quantum properties of optomechanical systems--without the need of any feedback and control, and within parameters reasonable in experimental settings. Entanglement dynamics is shown of states following classical quasiperiodic orbits in their first moments. We discuss the complex time dependence of the modes of a cavity-light field and a mechanical mode in phase space. Such settings give rise to certifiable quantum properties within experimental conditions feasible with present technology.
KCC2, best known as the neuron-specific chloride-extruder that sets the strength and polarity of GABAergic currents during neuronal maturation, is a multifunctional molecule that can regulate ...cytoskeletal dynamics via its C-terminal domain (CTD). We describe the molecular and cellular mechanisms involved in the multiple functions of KCC2 and its splice variants, ranging from developmental apoptosis and the control of early network events to the formation and plasticity of cortical dendritic spines. The versatility of KCC2 actions at the cellular and subcellular levels is also evident in mature neurons during plasticity, disease, and aging. Thus, KCC2 has emerged as one of the most important molecules that shape the overall neuronal phenotype.
KCC2 is a neuron-specific chloride-extruder that shapes cortical development.Changes in the strength of GABAergic synapses brought about by up- and downregulation of Cl− extrusion by KCC2 exert a major effect on neuronal plasticity and network functions.The structural interactions of the C terminus of KCC2 regulate signaling pathways involved in early neuronal survival, spinogenesis, and glutamatergic synaptic transmission.The recently discovered tertiary and quaternary structures of KCC2 and other cation/chloride cotransporter (CCC) members provide first insights into their functions at an atomic level.The multisite phosphorylation code of KCC2 controls its membrane expression and stability, as well as its intrinsic transport rate during development, plasticity, and disease.KCC2 mutations linked to epilepsy and autism spectrum disorder (ASD) disrupt both ion transport-dependent and -independent KCC2 functions, suggesting a novel molecular basis for CNS disorders related to the structural roles of KCC2.
Gasdermin‐D (GSDMD), a member of the gasdermin protein family, mediates pyroptosis in human and murine cells. Cleaved by inflammatory caspases, GSDMD inserts its N‐terminal domain (GSDMDNterm) into ...cellular membranes and assembles large oligomeric complexes permeabilizing the membrane. So far, the mechanisms of GSDMDNterm insertion, oligomerization, and pore formation are poorly understood. Here, we apply high‐resolution (≤ 2 nm) atomic force microscopy (AFM) to describe how GSDMDNterm inserts and assembles in membranes. We observe GSDMDNterm inserting into a variety of lipid compositions, among which phosphatidylinositide (PI(4,5)P2) increases and cholesterol reduces insertion. Once inserted, GSDMDNterm assembles arc‐, slit‐, and ring‐shaped oligomers, each of which being able to form transmembrane pores. This assembly and pore formation process is independent on whether GSDMD has been cleaved by caspase‐1, caspase‐4, or caspase‐5. Using time‐lapse AFM, we monitor how GSDMDNterm assembles into arc‐shaped oligomers that can transform into larger slit‐shaped and finally into stable ring‐shaped oligomers. Our observations translate into a mechanistic model of GSDMDNterm transmembrane pore assembly, which is likely shared within the gasdermin protein family.
Synopsis
Gasdermin‐D, which mediates pyroptosis in human and murine cells, is directly observed inserting into lipid membranes and assembling arc‐, slit‐ and ring‐shaped oligomers. The observations translate into a mechanistic model of gasdermin‐D assembling transmembrane lytic pores.
High‐resolution time‐lapse imaging of gasdermin‐D pore formation.
Gasdermin‐D assembles arc‐, slit‐ and ring‐shaped oligomers.
Arc‐ and slit‐shaped pores transform into stable ring‐shaped pores.
Phosphatidylinositide (PI(4,5)P2) increases gasdermin‐D pore formation.
Cholesterol reduces gasdermin‐D pore formation.
High‐resolution atomic force microscopy shows how a pyroptosis‐mediating gasdermin protein inserts into lipid membranes and assembles arc‐, slit‐ and ring‐shaped oligomers.
Social categorization involves two crucial processes: First, children seek properties on which they can categorize individuals, i.e., they learn to form social categories; then children make ...inferences based on social category membership and might develop affective responses toward social categories. Over the last decade, a growing number of research in developmental psychology started to use novel social categories to investigate how children learn and reason about social categories. To date, three types of cues have been put forward as means to form social categories, namely linguistic, visual, and behavioral cues. Based on social category membership, children draw inferences about the shared properties of social category members and about how social category members ought to behave and interact with each other. With additional input, children might apply essentialist beliefs to social categories and develop affective responses toward social categories. This article aims to provide key insights on the development of stereotypes and intergroup biases by reviewing recent works that investigated how children learn to form novel social categories and the kind of inferences they make about these novel social categories.
•The processes of social categorization are studied with novel social categories.•Linguistic, visual, and behavioral cues are used to introduce novel social categories.•Children make different inferences based on social category membership.•Cues to social categories impact children's inferences about category members.
We introduce the idea of actually cooling quantum systems by means of incoherent thermal light, hence giving rise to a counterintuitive mechanism of "cooling by heating." In this effect, the mere ...incoherent occupation of a quantum mechanical mode serves as a trigger to enhance the coupling between other modes. This notion of effectively rendering states more coherent by driving with incoherent thermal quantum noise is applied here to the optomechanical setting, where this effect occurs most naturally. We discuss two ways of describing this situation, one of them making use of stochastic sampling of gaussian quantum states with respect to stationary classical stochastic processes. The potential of experimentally demonstrating this counterintuitive effect in optomechanical systems with present technology is sketched.
This paper presents a study of the shear capacity of reinforced concrete (RC) beams strengthened in shear with externally bonded (EB) fiber reinforced polymer (FRP) composites, based on the ...performance of existing published tests. The main objective of this study is to create a comprehensive overview of the performance of different shear strengthening configurations and the failure modes observed in experimental tests. In addition, the influence of the following parameters on the strengthening efficiency has been analyzed: shear span to depth ratio (a/d), existing steel transverse reinforcement ratio (ρsw), concrete strength (fck), size effect (d), longitudinal reinforcement ratio (ρsL), strengthening configurations, type of FRP: sheets or laminates (CFRP, GFRP), and FRP axial stiffness (AfEf).
We introduce and characterize two different measures which quantify the level of synchronization of coupled continuous variable quantum systems. The two measures allow us to extend to the quantum ...domain the notions of complete and phase synchronization. The Heisenberg principle sets a universal bound to complete synchronization. The measure of phase synchronization is, in principle, unbounded; however, in the absence of quantum resources (e.g., squeezing) the synchronization level is bounded below a certain threshold. We elucidate some interesting connections between entanglement and synchronization and, finally, discuss an application based on quantum optomechanical systems.
Early-life environmental variation affects gut microbial colonization and immune competence development; however, the timing and additional specifics of these processes are unknown. The impact of ...early-life environmental variations, as experienced under real life circumstances, on gut microbial colonization and immune development has not been studied extensively so far. We designed a study to investigate environmental variation, experienced early after birth, to gut microbial colonization and intestinal immune development.
To investigate effects of early-life environmental changes, the piglets of 16 piglet litters were divided into 3 groups per litter and experimentally treated on day 4 after birth. During the course of the experiment, the piglets were kept with their mother sow. Group 1 was not treated, group 2 was treated with an antibiotic, and group 3 was treated with an antibiotic and simultaneously exposed to several routine, but stressful management procedures, including docking, clipping and weighing. Thereafter, treatment effects were measured at day 8 after birth in 16 piglets per treatment group by community-scale analysis of gut microbiota and genome-wide intestinal transcriptome profiling. We observed that the applied antibiotic treatment affected the composition and diversity of gut microbiota and reduced the expression of a large number of immune-related processes. The effect of management procedures on top of the use of an antibiotic was limited.
We provide direct evidence that different early-life conditions, specifically focusing on antibiotic treatment and exposure to stress, affect gut microbial colonization and intestinal immune development. This reinforces the notion that the early phase of life is critical for intestinal immune development, also under regular production circumstances.
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