Electrophysiological correlates of inhibitory control in children: Relations with prenatal maternal risk factors and child psychopathology.

Inhibitory control plays an important role in children's cognitive and socioemotional development, including their psychopathology. It has been established that contextual factors such as socioeconomic status (SES) and parents' psychopathology are associated with children's inhibitory control. However, the relations between the neural correlates of inhibitory control and contextual factors have been rarely examined in longitudinal studies. In the present study, we used both event-related potential (ERP) components and time-frequency measures of inhibitory control to evaluate the neural pathways between contextual factors, including prenatal SES and maternal psychopathology, and children's behavioral and emotional problems in a large sample of children (N = 560; 51.75% females; Mage = 7.13 years; Rangeage = 4-11 years). Results showed that theta power, which was positively predicted by prenatal SES and was negatively related to children's externalizing problems, mediated the longitudinal and negative relation between them. ERP amplitudes and latencies did not mediate the longitudinal association between prenatal risk factors (i.e., prenatal SES and maternal psychopathology) and children's internalizing and externalizing problems. Our findings increase our understanding of the neural pathways linking early risk factors to children's psychopathology.

Efficient learning of mixed-state tomography for photonic quantum walk.

Noise-enhanced applications in open quantum walk (QW) has recently seen a surge due to their ability to improve performance. However, verifying the success of open QW is challenging, as mixed-state tomography is a resource-intensive process, and implementing all required measurements is almost impossible due to various physical constraints. To address this challenge, we present a neural-network-based method for reconstructing mixed states with a high fidelity (∼97.5%) while costing only 50% of the number of measurements typically required for open discrete-time QW in one dimension. Our method uses a neural density operator that models the system and environment, followed by a generalized natural gradient descent procedure that significantly speeds up the training process. Moreover, we introduce a compact interferometric measurement device, improving the scalability of our photonic QW setup that enables experimental learning of mixed states. Our results demonstrate that highly expressive neural networks can serve as powerful alternatives to traditional state tomography.

Quercetin Ameliorates Deoxynivalenol-Induced Intestinal Injury and Barrier Dysfunction Associated with Inhibiting Necroptosis Signaling Pathway in Weaned Pigs.

Quercetin (Que) is a flavonol compound found in plants, which has a variety of biological activities. Necroptosis, a special form of programmed cell death, plays a vital role in the development of many gastrointestinal diseases. This study aimed to explore whether Que could attenuate the intestinal injury and barrier dysfunction of piglets after deoxynivalenol (DON) exposure through modulating the necroptosis signaling pathway. Firstly, twenty-four weaned piglets were used in a 2 × 2 factorial design and the main factors, including Que (basal diet or diet supplemented with 100 mg/kg Que) and DON exposure (control feed or feed contaminated with 4 mg/kg DON). After feeding for 21 d, piglets were killed for samples. Next, the intestinal porcine epithelial cell line (IPEC-1) was pretreated with or without Que (10 µmol/mL) in the presence or absence of a DON challenge (0.5 µg/mL). Dietary Que increased the body weight, average daily gain, and average daily feed intake (p < 0.05) through the trial. Que supplementation improved the villus height, and enhanced the intestinal barrier function (p < 0.05) indicated by the higher protein expression of occludin and claudin-1 (p < 0.05) in the jejunum of the weaned piglets after DON exposure. Dietary Que also down-regulated the protein abundance of total receptor interacting protein kinase 1 (t-RIP1), phosphorylated RIP1 (p-RIP1), p-RIP3, total mixed lineage kinase domain-like protein (t-MLKL), and p-MLKL (p < 0.05) in piglets after DON exposure. Moreover, Que pretreatment increased the cell viability and decreased the lactate dehydrogenase (LDH) activity (p < 0.05) in the supernatant of IPEC-1 cells after DON challenge. Que treatment also improved the epithelial barrier function indicated by a higher transepithelial electrical resistance (TEER) (p < 0.001), lower fluorescein isothiocyanate-labeled dextran (FD4) flux (p < 0.001), and better distribution of occludin and claudin-1 (p < 0.05) after DON challenge. Additionally, pretreatment with Que also inhibited the protein abundance of t-RIP1, p-RIP1, t-RIP3, p-RIP3, t-MLKL, and p-MLKL (p < 0.05) in IPEC-1 cells after DON challenge. In general, our data suggest that Que can ameliorate DON-induced intestinal injury and barrier dysfunction associated with suppressing the necroptosis signaling pathway.

White children's prosocial behavior toward White versus Black peers: The role of children's effortful control and parents' implicit racial attitudes.

White children's effortful control (EC), parents' implicit racial attitudes, and their interaction were examined as predictors of children's prosocial behavior toward White versus Black recipients. Data were collected from 171 White children (55% male, Mage = 7.13 years, SD = 0.92) and their parent in 2017. Prosocial behavior toward White peers was predicted by children's higher EC. When predicting prosocial behavior toward Black peers and prosocial disparity (the difference between White and Black recipients), parents' implicit racial attitudes moderated the relation between children's EC and children's prosocial behavior. Specifically, children's EC was positively associated with prosocial behavior toward Black peers (and negatively related to inequity in prosocial behavior) only when parents exhibited less implicit racial bias.

Parents' color-blind racial ideology and implicit racial attitudes predict children's race-based sympathy.

We examined the relation of White parents' color-blind racial attitudes (a global composite score and its subscales) and their implicit racial attitudes to their young children's race-based sympathy toward Black and White victims. One hundred and nighty non-Hispanic White children (54% boys, Mage = 7.13 years, SD = 0.92) reported their sympathy in response to short films depicting bullying toward White or Black children. Their primary caregivers' (mostly mothers') color-blind racial ideology (CBRI) was assessed through a questionnaire (reflecting global color blindness, as well as denial of institutional racism, White privilege, and blatant racial issues), and their implicit racial attitudes were assessed with a computerized test. Children's sympathy toward Black victims and their equitable sympathy (difference score toward Black vs. White victims) was predicted by parents' color blindness, implicit racial attitudes, and their interaction. Results indicated several interaction effects, such that parents' denial of blatant racial attitudes and global CBRI were negatively related to children's sympathy toward Black victims and equitable sympathy toward Black versus White victims, only when the parents held implicit racial attitudes that favored White people. In addition, parents' denial of White privilege was negatively related to children's sympathy toward Black victims. The findings are discussed in terms of potential ways to shape children's race-based sympathy and compassion, particularly with an eye toward ways White parents might socialize sympathy toward historically marginalized youth. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

White children's empathy-related responding and prosocial behavior toward White and Black children.

Relations among White (non-Latinx) children's empathy-related responding, prosocial behaviors, and racial attitudes toward White and Black peers were examined. In 2017, 190 (54% boys) White 5- to 9-year-old children (M = 7.09 years, SD = 0.94) watched a series of videos that depicted social rejection of either a White or Black child. Empathy-related responses, prosocial behaviors, and racial attitudes were measured using multiple methods. Results showed that younger children showed less facial concern toward Black than White peers and greater increases with age in concern and prosocial behaviors (sharing a desirable prize) for Black, compared to White, targets. Children's facial anger increased with age for White but not Black targets. The findings can extend our understanding children's anti-racism development.

Peripheral Iron Metabolism is Associated with Leg Movements on Polysomnography but Not with the Severity of Restless Legs Syndrome or Its Impact on Patients.

Purpose: This study investigated the associations of peripheral iron status with different manifestations of restless legs syndrome (RLS), including leg movements (LMs) on polysomnography (PSG), disease severity, and impact on patients. Patients and Methods: In this cross-sectional study, 108 patients with RLS were enrolled at Sir Run Run Shaw Hospital's Center for Sleep Medicine. Demographic information, disease characteristics, RLS severity, and impact on patients were assessed through a semi-structured questionnaire. Peripheral iron indicators [serum ferritin, iron, and transferrin concentrations; unsaturated iron-binding capacity (UIBC) and total iron-binding capacity (TIBC); transferrin saturation (TSAT)] were measured following PSG to assess sleep stages, respiratory events, microarousals and LM parameters. Data from patients with and without ferritin concentration < 50 µg/L were compared in crude analyses, and Spearman correlations of other iron indicators with RLS data were examined. An ordinal logistic regression model was used to adjust for age, sex, body mass index, years of education, age at the time of RLS onset, prior treatment (yes/no), C-reactive protein (CRP)/hemoglobin level, total sleep time and apnea-hypopnea index. Results: Multivariate analysis showed that periodic LMs during sleep (PLMS) and other LM parameters were significantly associated with a ferritin concentration < 50 µg/L, UIBC, TIBC, and serum transferrin concentration, but not serum iron or TSAT. By contrast, the severity and impact of RLS were not associated with a ferritin concentration < 50 µg/L or other peripheral iron indicators in the multivariate model. Conclusion: In this study, peripheral iron status was associated mainly with motor components (LMs on PSG) rather than sensory components (severity and impact of RLS) after adequately controlling for potential confounders, such as CRP and hemoglobin levels. Commonly used peripheral iron metabolism indicators may therefore not be ideal biomarkers of RLS severity or impact on patients.

Optical demonstration of quantum fault-tolerant threshold.

A major challenge in practical quantum computation is the ineludible errors caused by the interaction of quantum systems with their environment. Fault-tolerant schemes, in which logical qubits are encoded by several physical qubits, enable to the output of a higher probability of correct logical qubits under the presence of errors. However, strict requirements to encode qubits and operators render the implementation of a full fault-tolerant computation challenging even for the achievable noisy intermediate-scale quantum technology. Especially the threshold for fault-tolerant computation still lacks experimental verification. Here, based on an all-optical setup, we experimentally demonstrate the existence of the threshold for the fault-tolerant protocol. Four physical qubits are represented as the spatial modes of two entangled photons, which are used to encode two logical qubits. The experimental results clearly show that when the error rate is below the threshold, the probability of correct output in the circuit, formed with fault-tolerant gates, is higher than that in the corresponding non-encoded circuit. In contrast, when the error rate is above the threshold, no advantage is observed in the fault-tolerant implementation. The developed high-accuracy optical system may provide a reliable platform to investigate error propagation in more complex circuits with fault-tolerant gates.

Experimental verification of generalized eigenstate thermalization hypothesis in an integrable system.

Identifying the general mechanics behind the equilibration of a complex isolated quantum system towards a state described by only a few parameters has been the focus of attention in non-equilibrium thermodynamics. And several experimentally unproven conjectures are proposed for the statistical description of quantum (non-)integrable models. The plausible eigenstate thermalization hypothesis (ETH), which suggests that each energy eigenstate itself is thermal, plays a crucial role in understanding the quantum thermalization in non-integrable systems; it is commonly believed that it does not exist in integrable systems. Nevertheless, integrable systems can still relax to the generalized Gibbs ensemble. From a microscopic perspective, understanding the origin of this generalized thermalization that occurs in an isolated integrable system is a fundamental open question lacking experimental investigations. Herein, we experimentally investigated the spin subsystem relaxation in an isolated spin-orbit coupling quantum system. By applying the quantum state engineering technique, we initialized the system with various distribution widths in the mutual eigenbasis of the conserved quantities. Then, we compared the steady state of the spin subsystem reached in a long-time coherent dynamics to the prediction of a generalized version of ETH and the underlying mechanism of the generalized thermalization is experimentally verified for the first time. Our results facilitate understanding the origin of quantum statistical mechanics.

Activation of indistinguishability-based quantum coherence for enhanced metrological applications with particle statistics imprint.

SignificanceQuantum coherence has a fundamentally different origin for nonidentical and identical particles since for the latter a unique contribution exists due to indistinguishability. Here we experimentally show how to exploit, in a controllable fashion, the contribution to quantum coherence stemming from spatial indistinguishability. Our experiment also directly proves, on the same footing, the different role of particle statistics (bosons or fermions) in supplying coherence-enabled advantage for quantum metrology. Ultimately, our results provide insights toward viable quantum-enhanced technologies based on tunable indistinguishability of identical building blocks.

Longitudinal transactional relations among young children's defiance and committed compliance and maternal assertive control.

The main goal of this study was to more closely understand the direction of relations between maternal behavior and young children's defiance and committed compliance. We examined 256 mother-child dyads to explore developmental transactional relations between maternal assertive control, children's committed compliance, and children's defiance at 18 (T1), 30 (T2), and 42 (T3) months of age. After controlling for maternal gentle control, SES, and child sex, results showed parent effects for children's committed compliance, such that T1 maternal assertive control negatively predicted T3 committed compliance. Furthermore, toddlers' behavior predicted T3 parenting; that is, toddlers' T1 defiance positively predicted T3 maternal assertive control. Results of the present study indicate relatively long-term prediction (to 42 months) from both parent and child behaviors at 18 months of age, and the findings have implications for understanding the bidirectional and complex processes that account for young children's adaptive and maladaptive behaviors.

Experimental optimal generation of hybrid entangled states in photonic quantum walks.

While the existence of disorders is commonly believed to weaken the unique properties of quantum systems, recent progress has predicted that it can exhibit a counterintuitive enhanced effect on the behavior of entanglement generation, which is even independent of the chosen initial conditions and physical platforms. However, to achieve a maximally entangled state in such disordered quantum systems, the key limitation of this is the scarcity of an infinite coherence time, which makes its experimental realization challenging. Here, we experimentally investigate the entanglement entropy dynamics in a photonic quantum walk with disorders in time. Through the incorporation of a classic optimization algorithm, we experimentally demonstrate that such disordered systems can relax to a high-entanglement hybrid state at any given time step. Moreover, this prominent entangling ability is universal for a wide variety of initial conditions. Our results may inspire achieving a well-controlled entanglement generator for quantum computation and information tasks.

Experimental quantum entanglement and teleportation by tuning remote spatial indistinguishability of independent photons.

Quantitative control of spatial indistinguishability of identical subsystems as a direct quantum resource at distant sites has not yet been experimentally proven. We design a setup capable of tuning remote spatial indistinguishability of two independent photons by individually adjusting their spatial distribution in two distant regions, leading to polarization entanglement from uncorrelated photons. This is achieved by spatially localized operations and classical communication on photons that meet only at the detectors. The amount of entanglement depends uniquely on the degree of spatial indistinguishability, quantified by an entropic measure I, which enables teleportation with fidelities above the classical threshold. The results open the way to viable indistinguishability-enhanced quantum information processing.

Experimental Optimal Verification of Entangled States Using Local Measurements.

The initialization of a quantum system into a certain state is a crucial aspect of quantum information science. While a variety of measurement strategies have been developed to characterize how well the system is initialized, for a given one, there is in general a trade-off between its efficiency and the accessible information of the quantum state. Conventional quantum state tomography can characterize unknown states while requiring exponentially expensive time-consuming postprocessing. Alternatively, recent theoretical breakthroughs show that quantum state verification provides a technique to quantify the prepared state with significantly fewer samples, especially for multipartite entangled states. In this Letter, we modify the original proposal to be robust to practical imperfections, and experimentally implement a scalable quantum state verification on two-qubit and four-qubit entangled states with nonadaptive local measurements. For all the tested states, the estimated infidelity is inversely proportional to the number of samples, which illustrates the power to characterize a quantum state with a small number of samples. Compared to the globally optimal strategy which requires nonlocal measurements, the efficiency in our experiment is only worse by a small constant factor (<2.5). We compare the performance difference between quantum state verification and quantum state tomography in an experiment to characterize a four-photon Greenberger-Horne-Zeilinger state, and the results indicate the advantage of quantum state verification in both the achieved efficiency and precision.

Extracting information from single qubits among multiple observers with optimal weak measurements.

In the context of quantum information, major efforts have been made to maximize the mutual information by measuring single copies of signal states. In general, one execution of optimal projective measurement extracts all the accessible mutual information. However, in some scenarios, weak measurements are preferred because of kinds of specific requirements, e.g., to distribute secret keys to multi-observers. In this study, we propose a method to construct optimal weak measurements for multi-party quantum communications. Utilizing the method in [Physical Review Letters 120, 160501 (2018)] to classify the mutual information, the theoretical study shows that by successively performing this optimal weak measurement, all accessible information can be obtained by multiple observers. This conclusion is experimentally verified by a cascaded measurement apparatus that can perform six successive weak measurements on heralded single photons. The experimental results clearly indicate that almost all accessible mutual information is extracted by this sequence of optimal weak measurements; meanwhile, none of the information is destroyed or residual. Thus, this optimal weak measurement is an efficient and reliable tool for performing quantum communication tasks. The consistence between the experimental and theoretical results verifies that the classifying method in [Phys. Rev. Lett.120, 160501 (2018)] can be applied to characterize realistic quantum measurements.

Coherent Control of Nitrogen-Vacancy Center Spins in Silicon Carbide at Room Temperature.

Solid-state color centers with manipulatable spin qubits and telecom-ranged fluorescence are ideal platforms for quantum communications and distributed quantum computations. In this work, we coherently control the nitrogen-vacancy (NV) center spins in silicon carbide at room temperature, in which telecom-wavelength emission is detected. We increase the NV concentration sixfold through optimization of implantation conditions. Hence, coherent control of NV center spins is achieved at room temperature, and the coherence time T_{2} can be reached to around 17.1 µs. Furthermore, an investigation of fluorescence properties of single NV centers shows that they are room-temperature photostable single-photon sources at telecom range. Taking advantage of technologically mature materials, the experiment demonstrates that the NV centers in silicon carbide are promising platforms for large-scale integrated quantum photonics and long-distance quantum networks.

Experimental exchange of grins between quantum Cheshire cats.

Intuition suggests that an object should carry all of its physical properties. However, a quantum object may not act in such a manner-it can temporarily leave some of its physical properties where it never appears. This phenomenon is known as the quantum Cheshire cat effect. It has been proposed that a quantum object can even permanently discard a physical property and obtain a new one it did not initially have. Here, we observe this effect experimentally by casting non-unitary imaginary-time evolution on a photonic cluster state to extract weak values, which reveals the counterintuitive phenomenon that two photons exchange their spins without classically meeting each other. A phenomenon presenting only in the quantum realm, our results are in stark contrast with the perception of inseparability between objects and properties, and shed new light on comprehension of the ontology of observables.

Experimental extraction of nonlocal weak values for demonstrating the failure of a product rule.

We experimentally demonstrate an alternative method for measuring nonlocal weak values in linear optics, avoiding the use of second-order interaction. The method is based on the concept of modular values. The paths of two photons, initialized in hyperentangled states, are adopted as the meter with the polarization acting as the system. The modular values are read out through the reconstructed final states of the meter. The weak value of nonlocal observables is given through its connection to the modular value. Comparing the weak values of local and nonlocal observables, we demonstrate the failure of product rules for an entangled system. Our results significantly simplify the task of measuring nonlocal weak values and will play an important role in the application of weak measurement.

Measuring a dynamical topological order parameter in quantum walks.

Quantum processes of inherent dynamical nature, such as quantum walks, defy a description in terms of an equilibrium statistical physics ensemble. Until now, identifying the general principles behind the underlying unitary quantum dynamics has remained a key challenge. Here, we show and experimentally observe that split-step quantum walks admit a characterization in terms of a dynamical topological order parameter (DTOP). This integer-quantized DTOP measures, at a given time, the winding of the geometric phase accumulated by the wavefunction during a quantum walk. We observe distinct dynamical regimes in our experimentally realized quantum walks, and each regime can be attributed to a qualitatively different temporal behavior of the DTOP. Upon identifying an equivalent many-body problem, we reveal an intriguing connection between the nonanalytic changes of the DTOP in quantum walks and the occurrence of dynamical quantum phase transitions.

Longitudinal relations among household chaos, SES, and effortful control in the prediction of language skills in early childhood.

Previous research has shown that home environment plays an important role in children's early language skills. Yet, few researchers have examined the unique role of family-level factors (socioeconomic status [SES], household chaos) on children's learning or focused on the longitudinal processes that might explain their relations to children's early language skills. The goal of this study was to investigate the longitudinal relations from family SES, household chaos, and children's effortful control (EC) to children's language skills during early childhood, controlling for stability of the constructs. At Time (T1 i.e., 30 months), mothers reported family SES and children's vocabulary, and their own linguistic input was assessed during a free-play session with their child. At T1, T2 (i.e., 42 months), and T3 (i.e., 54 months), household chaos was reported by mothers, and children's EC was rated by mothers and nonparental caregivers and observed during a gift-delay task. At T3, children's expressive and receptive language skills were measured with a standard assessment. Path analyses indicated that higher SES predicted higher levels of EC at T2 and language skills at T3, and greater levels of household chaos at T2 predicted poorer EC and language skills a year later, even when controlling for stability of the constructs. Results indicated that T2 EC partially mediated the relations between SES and T3 language skills. Findings from this study can be used to identify key factors for early learning and perhaps inform programs designed to support families and young children. (PsycINFO Database Record (c) 2020 APA, all rights reserved).