Measuring the capabilities of quantum computers

As emerging next-generation information technologies, blockchains have unique advantages in information transparency and transaction security. They have attracted great attentions in social and financial fields. However, the rapid development of quantum computation and the impending realization of quantum supremacy have had significant impacts on the advantages of traditional blockchain based on traditional cryptography. Here, we propose a blockchain algorithm based on asymmetric quantum encryption and a stake vote consensus algorithm. The algorithm combines a consensus algorithm based on the delegated proof of stake with node behaviour and Borda count (DPoSB) and quantum digital signature technology based on quantum state computational distinguishability with a fully flipped permutation (\({\text{QSC}}{\text{D}}_{\text{ff}}\)) problem. DPoSB is used to generate blocks by voting, while the quantum signature applies quantum one-way functions to guarantee the security of transactions. The analysis shows that this combination offers better protection than other existing quantum-resistant blockchains. The combination can effectively resist the threat of quantum computation on blockchain technology and provide a new platform to ensure the security of blockchain.

Microsystems & Nanoengineering volume 8, Article number: 54 (2022) Cite this article. Integrated valves enable automated control in microfluidic systems, as they can be applied for mixing, pumping and compartmentalization purposes. Such automation would be highly valuable for applications in organ-on-chip (OoC) systems. However, OoC systems typically have channel dimensions in the range of hundreds of micrometers, which is an order of magnitude larger than those of typical microfluidic valves. The most-used fabrication process for integrated, normally open polydimethylsiloxane (PDMS) valves requires a reflow photoresist that limits the achievable channel height. In addition, the low stroke volumes of these valves make it challenging to achieve flow rates of microliters per minute, which are typically required in OoC systems. Herein, we present a mechanical 'macrovalve' fabricated by multilayer soft lithography using micromilled direct molds. We demonstrate that these valves can close off rounded channels of up to 700"‰Âµm high and 1000"‰Âµm wide. Furthermore, we used these macrovalves to create a peristaltic pump with a pumping rate of up to 48"‰ÂµL/min and a mixing and metering device that can achieve the complete mixing of a volume of 6.4"‰ÂµL within only 17"‰s. An initial cell culture experiment demonstrated that a device with integrated macrovalves is biocompatible and allows the cell culture of endothelial cells over multiple days under continuous perfusion and automated medium refreshment.

Sjögren's syndrome (SjS) is a female-dominated autoimmune disease involving lymphocytic infiltration of the exocrine glands. We have previously demonstrated cleavage of the TAM (Tyro3, Axl, Mer) receptor Mer is enhanced in SjS, leading to defective efferocytosis. Mer also plays a role in modulating phagocyte inflammatory response to apoptotic cells. Here we investigated the SjS macrophage response to apoptotic cells (AC). Bone marrow-derived macrophages (BMDMs) from SjS-susceptible (SjSs) C57BL/6.NOD-Aec1Aec2 mice and C57BL/6 (B6) controls were treated with either AC or CpG-oligodeoxynucleotides. RNA was collected from macrophages and bulk sequencing was performed to analyze transcripts. Cytokine expression was confirmed by Bio-plex. RT-qPCR was used to determine toll-like receptor (TLR) 7 and 9 involvement in BMDM inflammatory response to apoptotic cells. SjSS BMDMs exhibited a distinct transcriptional profile involving upregulation of a broad array of inflammatory genes that were not elevated in B6 BMDMs by AC. Inhibition of TLR 7 and 9 was found to limit the inflammatory response of SjSS BMDMs to ACs. ACs elicit an inflammatory reaction in SjSS BMDMs distinct from that observed in B6 BMDMs. This discovery of aberrant macrophage behavior in SjS in conjunction with previously described efferocytosis defects suggests an expanded role for macrophages in SjS, where uncleared dead cells stimulate an inflammatory response through macrophage TLRs recruiting lymphocytes, participating in co-stimulation and establishing an environment conducive to autoimmunity.

Intense phase-locked terahertz (THz) pulses are the bedrock of THz lightwave electronics, where the carrier field creates a transient bias to control electrons on sub-cycle time scales. Key applications such as THz scanning tunnelling microscopy or electronic devices operating at optical clock rates call for ultimately short, almost unipolar waveforms, at megahertz (MHz) repetition rates. Here, we present a flexible and scalable scheme for the generation of strong phase-locked THz pulses based on shift currents in type-II-aligned epitaxial semiconductor heterostructures. The measured THz waveforms exhibit only 0.45 optical cycles at their centre frequency within the full width at half maximum of the intensity envelope, peak fields above 1.1"‰kV"‰cm−1 and spectral components up to the mid-infrared, at a repetition rate of 4"‰MHz. The only positive half-cycle of this waveform exceeds all negative half-cycles by almost four times, which is unexpected from shift currents alone. Our detailed analysis reveals that local charging dynamics induces the pronounced positive THz-emission peak as electrons and holes approach charge neutrality after separation by the optical pump pulse, also enabling ultrabroadband operation. Our unipolar emitters mark a milestone for flexibly scalable, next-generation high-repetition-rate sources of intense and strongly asymmetric electric field transients.

We present a multiscale agent-based model of ductal carcinoma in situ (DCIS) to study how key phenotypic and signaling pathways are involved in the early stages of disease progression. The model includes a phenotypic hierarchy, and key endocrine and paracrine signaling pathways, and simulates cancer ductal growth in a 3D lattice-free domain. In particular, by considering stochastic cell dedifferentiation plasticity, the model allows for study of how dedifferentiation to a more stem-like phenotype plays key roles in the maintenance of cancer stem cell populations and disease progression. Through extensive parameter perturbation studies, we have quantified and ranked how DCIS is sensitive to perturbations in several key mechanisms that are instrumental to early disease development. Our studies reveal that long-term maintenance of multipotent stem-like cell niches within the tumor are dependent on cell dedifferentiation plasticity, and that disease progression will become arrested due to dilution of the multipotent stem-like population in the absence of dedifferentiation. We have identified dedifferentiation rates necessary to maintain biologically relevant multipotent cell populations, and also explored quantitative relationships between dedifferentiation rates and disease progression rates, which may potentially help to optimize the efficacy of emerging anti-cancer stem cell therapeutics.

Sequences of the human genome have typically included gaps in repetitive regions of DNA. A combination of state-of-the-art technologies has now enabled researchers to generate the first complete human genome sequence. John T. Lovell 0 &. John T. Lovell is at the Genome Sequencing Center, HudsonAlpha Institute for Biotechnology, Huntsville,...

We presented an effective and universal strategy for the improvement of luminophore's solid-state emission, i.e., macrocyclization-induced emission enhancement (MIEE), by linking luminophores through C(sp3) bridges to give a macrocycle. Benzothiadiazole-based macrocycle (BT-LC) has been synthesized by a one-step condensation of the monomer 4,7-bis(2,4-dimethoxyphenyl)−2,1,3-benzothiadiazole (BT-M) with paraformaldehyde, catalyzed by Lewis acid. In comparison with the monomer, macrocycle BT-LC produces much more intense fluorescence in the solid state (ΦPL"‰="‰99%) and exhibits better device performance in the application of OLEDs. Single-crystal analysis and theoretical simulations reveal that the monomer can return to the ground state through a minimum energy crossing point (MECPS1/S0), resulting in the decrease of fluorescence efficiency. For the macrocycle, its inherent structural rigidity prohibits this non-radiative relaxation process and promotes the radiative relaxation, therefore emitting intense fluorescence. More significantly, MIEE strategy has good universality that several macrocycles with different luminophores also display emission improvement.

The carbene and photocatalyst co-catalyzed radical coupling of acyl electrophile and a radical precursor is emerging as attractive method for ketone synthesis. However, previous reports mainly limited to prefunctionalized radical precursors and two-component coupling. Herein, an N-heterocyclic carbene and photocatalyst catalyzed decarboxylative radical coupling of carboxylic acids and acyl imidazoles is disclosed, in which the carboxylic acids are directly used as radical precursors. The acyl imidazoles could also be generated in situ by reaction of a carboxylic acid with CDI thus furnishing a formally decarboxylative coupling of two carboxylic acids. In addition, the reaction is successfully extended to three-component coupling by using alkene as a third coupling partner via a radical relay process. The mild conditions, operational simplicity, and use of carboxylic acids as the reacting partners make our method a powerful strategy for construction of complex ketones from readily available starting materials, and late-stage modification of natural products and medicines.

International Journal of Obesity (2022)Cite this article. Background: Syndromic obesity (SO) refers to obesity with additional phenotypes, including intellectual disability (ID)/developmental delay (DD), dysmorphic features, or organ-specific abnormalities. SO is rare, has high phenotypic variability, and frequently follows a monogenic pattern of inheritance. However, the genetic etiology of most cases of SO has not been elucidated. Subjects and methods: In this study, we investigated 20 SO patients by whole-exome sequencing (WES) trios to identify causal genetic variants. Results: 4/20 patients had negative results for array comparative genomic hybridization (aCGH) analyses. In the remaining 15 patients, in addition to SNVs and indels, CNVs were also evaluated. Pathogenic/likely pathogenic (P/LP) SNVs/indels were detected in 6/20 patients (involving MED13L, AHDC1, EHMT1, MYT1L, GRIA3, and SETD1A), while two patients carried an inherited VUS. In addition, P/LP CNVs were observed in 3/15 patients (involving SATG2, KIAA0442, and MEIS2). Conclusions: All nine detected P/LP variants involved genes already known to lead to syndromic ID/DD; however, for only two genes (EHMT1 and MYT1L) is the link with obesity well established. This is the first study applying a comprehensive genomic investigation of an SO cohort, showing a high diagnostic yield (~47%). Additionally, our findings suggested that several known ID/DD genes may also predispose individuals to SO.

Hydrogen peroxide has been synthesized mainly through the electrocatalytic and photocatalytic oxygen reduction reaction in recent years. Herein, we synthesize a single-atom rhodium catalyst (Rh1/NC) to mimic the properties of flavoenzymes for the synthesis of hydrogen peroxide under mild conditions. Rh1/NC dehydrogenates various substrates and catalyzes the reduction of oxygen to hydrogen peroxide. The maximum hydrogen peroxide production rate is 0.48"‰mol gcatalyst−1"‰h−1 in the phosphorous acid aerobic oxidation reaction. We find that the selectivity of oxygen reduction to hydrogen peroxide can reach 100%. This is because a single catalytic site of Rh1/NC can only catalyze the removal of two electrons per substrate molecule; thus, the subsequent oxygen can only obtain two electrons to reduce to hydrogen peroxide through the typical two-electron pathway. Similarly, due to the restriction of substrate dehydrogenation, the hydrogen peroxide selectivity in commercial Pt/C-catalyzed enzymatic reactions can be found to reach 75%, which is 30 times higher than that in electrocatalytic oxygen reduction reactions.

Solid-state photochemical reactions of olefinic compounds have been demonstrated to represent powerful access to organic cyclic molecules with specific configurations. However, the precise control of the stereochemistry in these reactions remains challenging owing to complex and fleeting configuration transformations. Herein, we report a unique approach to control the regiospecific configurations of C"‰="‰C groups and the intermediates by varying temperatures in multiple-step thermal/photoinduced reactions, thus successfully realizing reversible ring closing/opening changes using a single-crystal coordination polymer platform. All stereochemical transitions are observed by in situ single-crystal X-ray diffraction, powder X-ray diffraction and infrared spectroscopy. Density functional theory calculations allow us to rationalize the mechanism of the synergistic thermal/photoinduced transformations. This approach can be generalized to the analysis of the possible configuration transformations of functional groups and intermediates and unravel the detailed mechanism for any inorganic, organic and macromolecular reactions susceptible to incorporation into single-crystal coordination polymer platforms.

Stimulated emission depletion (STED) microscopy is a powerful diffraction-unlimited technique for fluorescence imaging. Despite its rapid evolution, STED fundamentally suffers from high-intensity light illumination, sophisticated probe-defined laser schemes, and limited photon budget of the probes. Here, we demonstrate a versatile strategy, stimulated-emission induced excitation depletion (STExD), to deplete the emission of multi-chromatic probes using a single pair of low-power, near-infrared (NIR), continuous-wave (CW) lasers with fixed wavelengths. With the effect of cascade amplified depletion in lanthanide upconversion systems, we achieve emission inhibition for a wide range of emitters (e.g., Nd3+, Yb3+, Er3+, Ho3+, Pr3+, Eu3+, Tm3+, Gd3+, and Tb3+) by manipulating their common sensitizer, i.e., Nd3+ ions, using a 1064-nm laser. With NaYF4:Nd nanoparticles, we demonstrate an ultrahigh depletion efficiency of 99.3"‰Â±"‰0.3% for the 450"‰nm emission with a low saturation intensity of 23.8"‰Â±"‰0.4"‰kW"‰cm−2. We further demonstrate nanoscopic imaging with a series of multi-chromatic nanoprobes with a lateral resolution down to 34"‰nm, two-color STExD imaging, and subcellular imaging of the immunolabelled actin filaments. The strategy expounded here promotes single wavelength-pair nanoscopy for multi-chromatic probes and for multi-color imaging under low-intensity-level NIR-II CW laser depletion.

UTe2 is a newly-discovered unconventional superconductor wherein multicomponent topological superconductivity is anticipated based on the presence of two superconducting transitions and time-reversal symmetry breaking in the superconducting state. The observation of two superconducting transitions, however, remains controversial. Here we demonstrate that UTe2 single crystals displaying an optimal superconducting transition temperature at 2 K exhibit a single transition and remarkably high quality supported by their large residual resistance ratio and small residual heat capacity in the superconducting state. Our results shed light on the intrinsic superconducting properties of UTe2 and bring into question whether UTe2 is a multicomponent superconductor at ambient pressure.

Rapid categorization of visual objects is critical for comprehending our complex visual world. The role of individual cortical neurons and neural populations in categorizing visual objects during passive vision has previously been studied. However, it is unclear whether and how perceptually guided behaviors affect the encoding of stimulus categories by neural population activity in the higher visual cortex. Here we studied the activity of the inferior temporal (IT) cortical neurons in macaque monkeys during both passive viewing and categorization of ambiguous body and object images. We found enhanced category information in the IT neural population activity during the correct, but not wrong, trials of the categorization task compared to the passive task. This encoding enhancement was task difficulty dependent with progressively larger values in trials with more ambiguous stimuli. Enhancement of IT neural population information for behaviorally relevant stimulus features suggests IT neural networks' involvement in perceptual decision-making behavior.

Searching for superconductivity with Tc near room temperature is of great interest both for fundamental science & many potential applications. Here we report the experimental discovery of superconductivity with maximum critical temperature (Tc) above 210"‰K in calcium superhydrides, the new alkali earth hydrides experimentally showing superconductivity above 200"‰K in addition to sulfur hydride & rare-earth hydride system. The materials are synthesized at the synergetic conditions of 160~190"‰GPa and ~2000 K using diamond anvil cell combined with in-situ laser heating technique. The superconductivity was studied through in-situ high pressure electric conductance measurements in an applied magnetic field for the sample quenched from high temperature while maintained at high pressures. The upper critical field Hc(0) was estimated to be ~268"‰T while the GL coherent length is ~11"‰Ã…. The in-situ synchrotron X-ray diffraction measurements suggest that the synthesized calcium hydrides are primarily composed of CaH6 while there may also exist other calcium hydrides with different hydrogen contents.

Arising from Albert C. Yang et al. Nature Communications https://doi.org/10.1038/s41467-018-05845-7 (2018) The empirical mode decomposition (EMD) method proposed in Yang et al.1 fails to correctly identify causal relationships for a system of two independent variables driven by a shared external forcing (aka Moran effect). Using a simple, two-species Moran effect model (Fig. 1a), it is obvious that the EMD method erroneously concludes that N1 and N2 have a causal relationship (IMF 1 in Fig. 1b), although in fact they do not. This is because effects of external forcing were recorded in both N1 and N2 time series, and at least one IMF decomposed from N1 and N2 time series is associated with that external forcing. Therefore, removal of such IMF from N1 makes the remaining less coherent with N2, and vice versa. As such, EMD methods based on diminished coherence due to IMF removals fail to falsify spurious causations caused by sharing external forcing. In contrast, convergent cross mapping (CCM) correctly identifies the lack-of causal relationship between N1 and N2 (Fig. 1c). The efficacy of CCM to distinguish Moran effects depends on the strength of the shared external forcing. In extreme cases, when external forcing is too strong, N1 and N2 are synchronized (the pathological case, as noted in a previous study2). Methods to cope with such situation have also been developed3,4.

Systematic review and meta-analysis of preclinical literature. To assess the effects of biomaterial-based combination (BMC) strategies for the treatment of Spinal Cord Injury (SCI), the effects of individual biomaterials in the context of BMC strategies, and the factors influencing their efficacy. To assess the effects of different preclinical testing paradigms in BMC strategies.

Interface engineering through passivating agents, in the form of organic molecules, is a powerful strategy to enhance the performance of perovskite solar cells. Despite its pivotal function in the development of a rational device optimization, the actual role played by the incorporation of interfacial modifications and the interface physics therein remains poorly understood. Here, we investigate the interface and device physics, quantifying charge recombination and charge losses in state-of-the-art inverted solar cells with power conversion efficiency beyond 23% - among the highest reported so far - by using multidimensional photoluminescence imaging. By doing that we extract physical parameters such as quasi-Fermi level splitting (QFLS) and Urbach energy enabling us to assess that the main passivation mechanism affects the perovskite/PCBM ([6,6]-phenyl-C61-butyric acid methyl ester) interface rather than surface defects. In this work, by linking optical, electrical measurements and modelling we highlight the benefits of organic passivation, made in this case by phenylethylammonium (PEAI) based cations, in maximising all the photovoltaic figures of merit.

Earth's earliest fossils of complex macroscopic life are recorded in Ediacaran-aged siliciclastic deposits as exceptionally well-preserved three-dimensional casts and molds, known as "Ediacara-style" preservation. Ediacara-style fossil assemblages commonly include both macrofossils of the enigmatic Ediacara Biota and associated textural impressions attributed to microbial matgrounds that were integral to the ecology of Ediacara communities. Here, we use an experimental approach to interrogate to what extent the presence of mat-forming microorganisms was likewise critical to the Ediacara-style fossilization of these soft-bodied organisms. We find evidence that biofilms can play an instrumental role in fostering fossilization. Rapid silica precipitation associated with macroorganism tissues is enhanced in the presence of mat- and biofilm-forming microorganisms. These results indicate that the occurrence of microbial mats and biofilms may have strongly shaped the preservational window for Ediacara-style fossils associated with early diagenetic silica cements, and therefore influenced the distribution and palaeoecological interpretation of the Ediacara Biota fossil record.

This work provides an EEG dataset collected from nine mice during the sleep deprivation (SD) paradigm for the sleep science community. It includes 9-day of continuous recording of the frontal and parietal EEG, accelerometer, and 2-hour of high-density EEG (HD-EEG) under SD and SD-free conditions. Eighteen hours of SD were conducted on 5 consecutive days. The HD-EEG data were saved in the EEGLAB format and stored as the brain imaging data structure (BIDS). These datasets can be used to (i) compare mouse HD-EEG to human HD-EEG, (ii) track oscillatory activities of the sleep EEG (e.g., slow waves, spindles) across the cortical regions under different conditions of sleep pressure, and (iii) investigate the cortical traveling waves in the mouse brain. We also provided Python code for basic analyses of this dataset, including the detection of slow waves and sleep spindles. We hope that our dataset will reveal hidden activities during sleep and lead to a better understanding of the functions and mechanisms of sleep.