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Simultaneous dyeing and antibacterial finishing of polypropylene using vinyl sulfone dye under supercritical carbon dioxide
Polypropylene fibres are difficult to dye using commonly used techniques due to the high crystallinity and non-polar aliphatic structure, that lack reactive places for dyes in the molecule. Dyeing PP fabric in scCO2 with antibacterial dyes merged the dyeing and finishing methods, resulting in a more productive technique in terms of water and energy consumption. Unmodified polypropylene fabric was dyed with 4-[2-[4-(ethenylsulphonyl)phenyl]diazenyl]-N,N-diethylbenzenamine antibacterial dye under scCO2 medium. The influences of scCO2 working parameters, such as dye concentration, pressure, dyeing time, and temperature, on fabric dye absorption expressed as color strength were studied. The color strength (K/S) was measured as well as CIELAB color parameters. The results were compared with its water dyeing analogue and it was observed that color strength as well as color depth (L) of the samples dyed in scCO2 were noticeably better than its water counterpart. In both scCO2 and water, the fastness properties (washing, rubbing, and light) of the dyed samples were excellent. Antibacterial activity of the dyed polypropylene sample in scCO2 was estimated and the results indicated good antibacterial efficiency.
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Cobalt-electrocatalytic HAT for functionalization of unsaturated C"“C bonds
The study and application of transition metal hydrides (TMHs) has been an active area of chemical research since the early 1960s1, for energy storage, through the reduction of protons to generate hydrogen2,3, and for organic synthesis, for the functionalization of unsaturated C"“C, C"“O and C"“N bonds4,5. In the former instance, electrochemical means for driving such reactivity has been common place since the 1950s6 but the use of stoichiometric exogenous organic- and metal-based reductants to harness the power of TMHs in synthetic chemistry remains the norm. In particular, cobalt-based TMHs have found widespread use for the derivatization of olefins and alkynes in complex molecule construction, often by a net hydrogen atom transfer (HAT)7. Here we show how an electrocatalytic approach inspired by decades of energy storage research can be made use of in the context of modern organic synthesis. This strategy not only offers benefits in terms of sustainability and efficiency but also enables enhanced chemoselectivity and distinct, tunable reactivity. Ten different reaction manifolds across dozens of substrates are exemplified, along with detailed mechanistic insights into this scalable electrochemical entry into Co"“H generation that takes place through a low-valent intermediate.
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Neural network-based prediction of the secret-key rate of quantum key distribution
Numerical methods are widely used to calculate the secure key rate of many quantum key distribution protocols in practice, but they consume many computing resources and are too time-consuming. In this work, we take the homodyne detection discrete-modulated continuous-variable quantum key distribution (CV-QKD) as an example, and construct a neural network that can quickly predict the secure key rate based on the experimental parameters and experimental results. Compared to traditional numerical methods, the speed of the neural network is improved by several orders of magnitude. Importantly, the predicted key rates are not only highly accurate but also highly likely to be secure. This allows the secure key rate of discrete-modulated CV-QKD to be extracted in real time on a low-power platform. Furthermore, our method is versatile and can be extended to quickly calculate the complex secure key rates of various other unstructured quantum key distribution protocols.
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Reply to: Reassessment of the catalytic activity of bismuth for aqueous nitrogen electroreduction
Replying to J. Choi et al. Nature Catalysis https://doi.org/10.1038/s41929-022-00785-4 (2022) Get immediate online access to the entire Nature family of 50+ journals. All prices are NET prices. VAT will be added later in the checkout. Tax calculation will be finalised during checkout. Buy article. Get time limited or full article...
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Electrically tunable quantum confinement of neutral excitons
Confining particles to distances below their de Broglie wavelength discretizes their motional state. This fundamental effect is observed in many physical systems, ranging from electrons confined in atoms or quantum dots1,2 to ultracold atoms trapped in optical tweezers3,4. In solid-state photonics, a long-standing goal has been to achieve fully tunable quantum confinement of optically active electron"“hole pairs, known as excitons. To confine excitons, existing approaches mainly rely on material modulation5, which suffers from poor control over the energy and position of trapping potentials. This has severely impeded the engineering of large-scale quantum photonic systems. Here we demonstrate electrically controlled quantum confinement of neutral excitons in 2D semiconductors. By combining gate-defined in-plane electric fields with inherent interactions between excitons and free charges in a lateral p"“i"“n junction, we achieve exciton confinement below 10"‰nm. Quantization of excitonic motion manifests in the measured optical response as a ladder of discrete voltage-dependent states below the continuum. Furthermore, we observe that our confining potentials lead to a strong modification of the relative wave function of excitons. Our technique provides an experimental route towards creating scalable arrays of identical single-photon sources and has wide-ranging implications for realizing strongly correlated photonic phases6,7 and on-chip optical quantum information processors8,9.
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Tea consumption and gastric cancer: a pooled analysis from the Stomach cancer Pooling (StoP) Project consortium
Evidence from epidemiological studies on the role of tea drinking in gastric cancer risk remains inconsistent. We aimed to investigate and quantify the relationship between tea consumption and gastric cancer in the Stomach cancer Pooling (StoP) Project consortium. Methods. A total of 9438 cases and 20,451 controls from 22 studies...
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NF90"“NF45 is essential for β cell compensation under obesity-inducing metabolic stress through suppression of p53 signaling pathway
The Nuclear Factor 90 (NF90)"“NF45 complex has been known to regulate the progression of transcription, mRNA stability, translational inhibition, RNA export and microRNA biogenesis. However, the physiological functions of the NF90"“NF45 complex remain unclear. We newly discovered that the NF90"“NF45 complex was expressed in primary β cells and established cell lines. Therefore, in this study, we focused on the function of the endogenous NF90"“NF45 complex in the β cells. To investigate this issue, we generated β-cell-specific NF90"“NF45 deficient mice. These mice exhibited hyperglycaemia and lower plasma insulin levels under a high fat diet together with decreased islet mass. To uncover this mechanism, we performed a whole-genome expression microarray of the total RNA prepared from β cell lines treated with siRNAs targeting both NF90 and NF45. In this result, we found an activation of p53 signaling in the NF90"“NF45-knockdown cells. This activation was supported by elevation of luciferase activity derived from a reporter plasmid harboring p53 binding sites in the NF90"“NF45-knockdown cells. Furthermore, the knockdown of NF90"“NF45 resulted in a significant retardation of the β cell line growth rates. Importantly, a dominant negative form of p53 rescues the growth retardation in BTC6 cells depleted of NF90"“NF45, suggesting that NF90"“NF45 would be positively involved in β cell proliferation through suppression of p53 signal pathway. Taken together, NF90"“NF45 is essential for β cell compensation under obesity-inducing metabolic stress via repression of p53 signaling.
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Realizing repeated quantum error correction in a distance-three surface code
Quantum computers hold the promise of solving computational problems that are intractable using conventional methods1. For fault-tolerant operation, quantum computers must correct errors occurring owing to unavoidable decoherence and limited control accuracy2. Here we demonstrate quantum error correction using the surface code, which is known for its exceptionally high tolerance to errors3,4,5,6. Using 17 physical qubits in a superconducting circuit, we encode quantum information in a distance-three logical qubit, building on recent distance-two error-detection experiments7,8,9. In an error-correction cycle taking only 1.1"‰Î¼s, we demonstrate the preservation of four cardinal states of the logical qubit. Repeatedly executing the cycle, we measure and decode both bit-flip and phase-flip error syndromes using a minimum-weight perfect-matching algorithm in an error-model-free approach and apply corrections in post-processing. We find a low logical error probability of 3% per cycle when rejecting experimental runs in which leakage is detected. The measured characteristics of our device agree well with a numerical model. Our demonstration of repeated, fast and high-performance quantum error-correction cycles, together with recent advances in ion traps10, support our understanding that fault-tolerant quantum computation will be practically realizable.
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Frustration over Chinese academic database charges
China Agricultural University, Beijing, China. China Agricultural University, Beijing, China. Institute of Apicultural Research, Beijing, China. The Chinese Academy of Sciences last month suspended its use of the country’s largest science database — called China National Knowledge Infrastructure (CNKI; www.cnki.net) — because of a steep rise in subscription fees. The prohibitive charges threaten to cripple the country’s research programmes by hindering the dissemination and utilization of knowledge.
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Impact of obesity on cervical ossification of the posterior longitudinal ligament: a nationwide prospective study
Positive association between ossification of the posterior longitudinal ligament of the spine (OPLL) and obesity is widely recognized; however, few studies focused on the effects of obesity on treatment of cervical OPLL. The effects of obesity on surgical treatment of cervical OPLL were investigated by a Japanese nationwide, prospective study. Overall, 478 patients with cervical myelopathy due to OPLL were prospectively enrolled. To clarify the effects of obesity on the surgical treatment for cervical OPLL, patients were stratified into two groups, non-obese (<"‰BMI 30.0 kg/m2) and obese (≥"‰BMI 30.0 kg/m2) groups. The mean age of the obese group was significantly younger than that of non-obese group. There were no significant differences between the two groups in other demographic information, medical history, and clinical and radiographical findings. Alternatively, the obese group had a significantly higher rate of surgical site infection (SSI) than that of non-obese group. Approach-specific analyses revealed that the SSI was significantly higher in the obese group than in the non-obese group. A logistic regression analysis revealed that age, BMI, and duration of symptoms were significant factors affecting the postoperative minimum clinically important difference success. The result of this study provides useful information for future cervical OPLL treatment.
Nature.com
Effective hole conductivity in nitrogen-doped CVD-graphene by singlet oxygen treatment under photoactivation conditions
Nitrogen substitutional doping in the Ï€-basal plane of graphene has been used to modulate the material properties and in particular the transition from hole to electron conduction, thus enlarging the field of potential applications. Depending on the doping procedure, nitrogen moieties mainly include graphitic-N, combined with pyrrolic-N and pyridinic-N. However, pyridine and pyrrole configurations of nitrogen are predominantly introduced in monolayer graphene:N lattice as prepared by CVD. In this study, we investigate the possibility of employing pyridinic-nitrogen as a reactive site as well as activate a reactive center at the adjacent carbon atoms in the functionalized C"“N bonds, for additional post reaction like oxidation. Furthermore, the photocatalytic activity of the graphene:N surface in the production of singlet oxygen (1O2) is fully exploited for the oxidation of the graphene basal plane with the formation of pyridine N-oxide and pyridone structures, both having zwitterion forms with a strong p-doping effect. A sheet resistance value as low as 100 Ω/â–¡ is reported for a 3-layer stacked graphene:N film.
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Comparative transcriptome profiles of human dental pulp stem cells from maxillary and mandibular teeth
The molecular control of tooth development is different between the maxilla and mandible, contributing to different tooth shapes and locations; however, whether this difference occurs in human permanent teeth is unknown. The aim of this study was to investigate and compare the transcriptome profiles of permanent maxillary and mandibular posterior teeth. Ten participants who had a pair of opposing premolars or molars extracted were recruited. The RNA obtained from cultured dental pulp stem cells underwent RNA-sequencing and qRT-PCR. The transcriptome profiles of two opposing premolar pairs and two molar pairs demonstrated that the upper premolars, lower premolars, upper molars, and lower molars expressed the same top-ranked genes, comprising FN1, COL1A1, COL1A2, ACTB, and EEFIA1, which are involved in extracellular matrix organization, immune system, signal transduction, hemostasis, and vesicle-mediated transport. Comparative transcriptome analyses of each/combined tooth pairs demonstrated that PITX1 was the only gene with different expression levels between upper and lower posterior teeth. PITX1 exhibited a 64-fold and 116-fold higher expression level in lower teeth compared with their upper premolars and molars, respectively. These differences were confirmed by qRT-PCR. Taken together, this study, for the first time, reveals that PITX1 is expressed significantly higher in mandibular posterior teeth compared with maxillary posterior teeth. The difference is more evident in the molars compared with premolars and consistent with its expression pattern in mouse developing teeth. We demonstrate that differences in lower versus upper teeth gene expression during odontogenesis occur in permanent teeth and suggest that these differences should be considered in molecular studies of dental pulp stem cells. Our findings pave the way to develop a more precise treatment in regenerative dentistry such as gene-based therapies for dentin/pulp regeneration and regeneration of different tooth types.
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Demonstration of fault-tolerant universal quantum gate operations
Quantum computers can be protected from noise by encoding the logical quantum information redundantly into multiple qubits using error-correcting codes1,2. When manipulating the logical quantum states, it is imperative that errors caused by imperfect operations do not spread uncontrollably through the quantum register. This requires that all operations on the quantum register obey a fault-tolerant circuit design3,4,5, which, in general, increases the complexity of the implementation. Here we demonstrate a fault-tolerant universal set of gates on two logical qubits in a trapped-ion quantum computer. In particular, we make use of the recently introduced paradigm of flag fault tolerance, where the absence or presence of dangerous errors is heralded by the use of auxiliary flag qubits6,7,8,9,10. We perform a logical two-qubit controlled-NOT gate between two instances of the seven-qubit colour code11,12, and fault-tolerantly prepare a logical magic state8,13. We then realize a fault-tolerant logical T gate by injecting the magic state by teleportation from one logical qubit onto the other14. We observe the hallmark feature of fault tolerance-a superior performance compared with a non-fault-tolerant implementation. In combination with recently demonstrated repeated quantum error-correction cycles15,16, these results provide a route towards error-corrected universal quantum computation.
Nature.com
An integrated multiomic approach as an excellent tool for the diagnosis of metabolic diseases: our first 3720 patients
European Journal of Human Genetics (2022)Cite this article. To present our experience using a multiomic approach, which integrates genetic and biochemical testing as a first-line diagnostic tool for patients with inherited metabolic disorders (IMDs). A cohort of 3720 patients from 62 countries was tested using a panel including 206 genes with single nucleotide and copy number variant (SNV/CNV) detection, followed by semi-automatic variant filtering and reflex biochemical testing (25 assays). In 1389 patients (37%), a genetic diagnosis was achieved. Within this cohort, the highest diagnostic yield was obtained for patients from Asia (57.5%, mainly from Pakistan). Overall, 701 pathogenic/likely pathogenic unique SNVs and 40 CNVs were identified. In 620 patients, the result of the biochemical tests guided variant classification and reporting. Top five diagnosed diseases were: Gaucher disease, Niemann-Pick disease type A/B, phenylketonuria, mucopolysaccharidosis type I, and Wilson disease. We show that integrated genetic and biochemical testing facilitated the decision on clinical relevance of the variants and led to a high diagnostic yield (37%), which is comparable to exome/genome sequencing. More importantly, up to 43% of these patients (n"‰="‰610) could benefit from medical treatments (e.g., enzyme replacement therapy). This multiomic approach constitutes a unique and highly effective tool for the genetic diagnosis of IMDs.
Nature.com
Advancing therapy for neuroblastoma
Nature Reviews Clinical Oncology (2022)Cite this article. Neuroblastomas are tumours of sympathetic origin, with a heterogeneous clinical course ranging from localized or spontaneously regressing to widely metastatic disease. Neuroblastomas recapitulate many of the features of sympathoadrenal development, which have been directly targeted to improve the survival outcomes in patients with high-risk disease. Over the past few decades, improvements in the 5-year survival of patients with metastatic neuroblastomas, from <20% to >50%, have resulted from clinical trials incorporating high-dose chemotherapy with autologous stem cell transplantation, differentiating agents and immunotherapy with anti-GD2 monoclonal antibodies. The next generation of trials are designed to improve the initial response rates in patients with high-risk neuroblastomas via the addition of immunotherapies, targeted therapies (such as ALK inhibitors) and radiopharmaceuticals to standard induction regimens. Other trials are focused on testing precision medicine strategies for patients with relapsed and/or refractory disease, enhancing the antitumour immune response and improving the effectiveness of maintenance regimens, in order to prolong disease remission. In this Review, we describe advances in delineating the pathogenesis of neuroblastoma and in identifying the drivers of high-risk disease. We then discuss how this knowledge has informed improvements in risk stratification, risk-adapted therapy and the development of novel therapies.
Nature.com
Bayesian optimization and deep learning for steering wheel angle prediction
Automated driving systems (ADS) have undergone a significant improvement in the last years. ADS and more precisely self-driving cars technologies will change the way we perceive and know the world of transportation systems in terms of user experience, mode choices and business models. The emerging field of Deep Learning (DL) has been successfully applied for the development of innovative ADS solutions. However, the attempt to single out the best deep neural network architecture and tuning its hyperparameters are all expensive processes, both in terms of time and computational resources. In this work, Bayesian optimization (BO) is used to optimize the hyperparameters of a Spatiotemporal-Long Short Term Memory (ST-LSTM) network with the aim to obtain an accurate model for the prediction of the steering angle in a ADS. BO was able to identify, within a limited number of trials, a model-namely BO_ST-LSTM-which resulted, on a public dataset, the most accurate when compared to classical end-to-end driving models.
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A harmless bird virus shows ominous changes
A type of bird virus not previously found to be harmful is developing mutations that could cause more severe disease and enable faster replication in poultry than was previously thought1. Access options. Subscribe to Nature+. Get immediate online access to the entire Nature family of 50+ journals. $29.99. monthly. Subscribe...
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Fossil biomolecules reveal an avian metabolism in the ancestral dinosaur
Birds and mammals independently evolved the highest metabolic rates among living animals1. Their metabolism generates heat that enables active thermoregulation1, shaping the ecological niches they can occupy and their adaptability to environmental change2. The metabolic performance of birds, which exceeds that of mammals, is thought to have evolved along their stem lineage3,4,5,6,7,8,9,10. However, there is no proxy that enables the direct reconstruction of metabolic rates from fossils. Here we use in situ Raman and Fourier-transform infrared spectroscopy to quantify the in vivo accumulation of metabolic lipoxidation signals in modern and fossil amniote bones. We observe no correlation between atmospheric oxygen concentrations11 and metabolic rates. Inferred ancestral states reveal that the metabolic rates consistent with endothermy evolved independently in mammals and plesiosaurs, and are ancestral to ornithodirans, with increasing rates along the avian lineage. High metabolic rates were acquired in pterosaurs, ornithischians, sauropods and theropods well before the advent of energetically costly adaptations, such as flight in birds. Although they had higher metabolic rates ancestrally, ornithischians reduced their metabolic abilities towards ectothermy. The physiological activities of such ectotherms were dependent on environmental and behavioural thermoregulation12, in contrast to the active lifestyles of endotherms1. Giant sauropods and theropods were not gigantothermic9,10, but true endotherms. Endothermy in many Late Cretaceous taxa, in addition to crown mammals and birds, suggests that attributes other than metabolism determined their fate during the terminal Cretaceous mass extinction.
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Variation spectrum of MECP2 in Korean patients with Rett and Rett-like syndrome: a literature review and reevaluation of variants based on the ClinGen guideline
Rett syndrome (RTT) is a progressive neurodevelopmental disorder caused by variants in MECP2. Emerging evidence of ethnic specificity of genetic variations has allowed precise diagnostic approaches with tailored therapies. In this study, we reviewed the variation spectrum of MECP2 in Korean RTT(-like)Â patients and compared it with previous reports in multiple ethnic groups. We reevaluated variants found in Korean RTTÂ patients according to the new Clinical Genome Resource guideline to reinterpret and reclassify variants of uncertain significance in MECP2. Among 377 cases, 56 (14.9%) showed pathogenic variants, and three novel variants, p.(Ala277Argfs*7), p.(Ala378Glyfs*8), and p.(Arg270_Ser332del), were identified. Comprehensive data from Korea revealed an overall consistent variation spectrum with those from other ethnicities. Through the reevaluation of variants, nine that previously had insufficient evidence for pathogenicity were reclassified into pathogenic variants. Our study provided insight on the genetic contribution of MECP2 in RTT and a useful background for genetic counseling in the Korean population.
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Quantitative evaluation of emphysema for predicting immunotherapy response in patients with advanced non-small-cell lung cancer
The efficacy of immune checkpoint inhibitors (ICIs) in patients with advanced non-small-cell lung cancer (NSCLC) might depend on the presence of emphysema, but this association is not established. We aimed to investigate if quantitively and automatically measuring emphysema can predict the effect of ICIs. We retrospectively analyzed 56 patients with NSCLC who underwent immunotherapy at our hospital. We used the Goddard scoring system (GS) to evaluate the severity of emphysema on baseline CT scans using three-dimensional image analysis software. The emphysema group (GS"‰â‰¥"‰1) showed better progression-free survival (PFS) than the non-emphysema group (GS"‰="‰0) (6.5 vs. 2.3 months, respectively, p"‰<"‰0.01). Multivariate analyses revealed that good performance status, GS of ≥"‰1, and high expression of PD-L1 were independently associated with better PFS, while smoking status was not. In conclusion, quantitative evaluation of emphysema can be an objective parameter for predicting the therapeutic effects of ICIs in patients with NSCLC. Our findings can be used to generate hypotheses for future studies.
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